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Longitudinal

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Distribution within Medical Sciences
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48 Other Subdomains80%

Terms modified by Longitudinal

  • longitudinal aging study amsterdam
  • longitudinal analysis
  • longitudinal approach
  • longitudinal arch
  • longitudinal assessment
  • longitudinal association
  • longitudinal binary data
  • longitudinal case studies
  • longitudinal case study
  • longitudinal categorical data
  • longitudinal change
  • longitudinal clinical trials
  • longitudinal cohort
  • longitudinal cohort study
  • longitudinal community study
  • longitudinal comparison
  • longitudinal component
  • longitudinal course
  • longitudinal data
  • longitudinal data analysis
  • longitudinal data set
  • longitudinal design
  • longitudinal development
    		•
  • longitudinal diameter
  • longitudinal direction
  • longitudinal distribution
  • longitudinal effects
  • longitudinal evaluation
  • longitudinal evidence
  • longitudinal examination
  • longitudinal fascicle
  • longitudinal fiber
  • longitudinal fin
  • longitudinal finding
  • longitudinal fissure
  • longitudinal follow-up
  • longitudinal force
  • longitudinal gradient
  • longitudinal growth
  • longitudinal incision
  • longitudinal influence
  • longitudinal information
  • longitudinal investigation
  • longitudinal magnetic field
  • longitudinal magnetization
  • longitudinal measure
    		•
  • longitudinal measurement
  • longitudinal mode
  • longitudinal model
  • longitudinal models
  • longitudinal monitoring
  • longitudinal movement
  • longitudinal muscle
  • longitudinal muscle layer
  • longitudinal muscle strip
  • longitudinal observation
  • longitudinal observational study
  • longitudinal optical
  • longitudinal outcome
  • longitudinal pattern
  • longitudinal perspective
  • longitudinal population
  • longitudinal profile
  • longitudinal project
  • longitudinal prospective study
  • longitudinal qualitative study
  • longitudinal relation
  • longitudinal relationship
  • longitudinal relationships
    		•
  • longitudinal relaxation
  • longitudinal research
  • longitudinal research design
  • longitudinal response
  • longitudinal result
  • longitudinal sample
  • longitudinal section
  • longitudinal setting
  • longitudinal smooth muscle
  • longitudinal stability
  • longitudinal strain
  • longitudinal strip
  • longitudinal studies
  • longitudinal study
  • longitudinal survey
  • longitudinal trajectory
  • longitudinal trend
  • longitudinal trial
  • longitudinal variation

    • Selected Abstracts

    RECOGNIZING GOOD ATTENDANCE: A LONGITUDINAL, QUASI-EXPERIMENTAL FIELD STUDY

    PERSONNEL PSYCHOLOGY, Issue 3 2002
    STEVEN E. MARKHAM
    Three motivational theories (need, goal, and reinforcement) suggest that recognition programs should increase employee attendance. A 1-year, quasi-experimental field study of absenteeism was conducted at 4 manufacturing plants with a total 1,100 employees. The study compared a public recognition program for improving work attendance with 3 types of controls. The personal recognition treatment showed (a) significant decreases ranging from 29% to 52% for each quarter's baseline assessment, and (b) significant decreases when the control groups showed no decrease. Employees had favorable perceptions of the public recognition program. [source]

    Combined Longitudinal and Radial Dyssynchrony Predicts Ventricular Response After Resynchronization Therapy

    CONGESTIVE HEART FAILURE, Issue 2 2008
    Article first published online: 2 MAY 200
    No abstract is available for this article. [source]

    The Role of Lad Magazines in Priming Men's Chronic and Temporary Appearance-Related Schemata: An Investigation of Longitudinal and Experimental Findings

    HUMAN COMMUNICATION RESEARCH, Issue 1 2009
    Jennifer Stevens Aubrey
    We present a program of research investigating the effects of lad magazines on male body self-consciousness and appearance anxiety. Study 1, based on panel data from undergraduate men, showed that lad magazine exposure in Year 1 predicted body self-consciousness in Year 2. Study 2 was an experiment that showed that men assigned to view objectified women in lad magazines reported significantly higher levels of appearance anxiety and appearance-related motivations for exercise than men assigned to view male fashion models. We speculated that participants believed that to be romantically successful with these women would require them to conform to an idealized appearance standard. Study 3 replicated the finding that exposure to sexually objectified women primed body self-consciousness, and it further showed that this effect was mediated by romantic confidence. Résumé Le rôle des magazines masculins dans le déclenchement de schémas chroniques et temporaires liés à l'apparence : une étude de résultats longitudinaux et expérimentaux Nous présentons un programme de recherche étudiant les effets des magazines masculins sur la gêne par rapport au corps et sur les inquiétudes liées à l,apparence chez les hommes. La première étude, fondée sur des données recueillies au moyen d'un panel auprès d,hommes étudiant au premier cycle universitaire, démontre que l'exposition aux magazines masculins à l,année 1 a prédit la gêne par rapport à son corps à l'année 2. La deuxième étude a démontré que les hommes assignés à voir des femmes objectivées dans les magazines masculins ont déclaré des niveaux d,inquiétude face à leur apparence et des niveaux d'intentions, liées à l,apparence, de faire de l'exercice beaucoup plus hauts que les hommes assignés à regarder des mannequins masculins. Nous avons spéculé que les participants croyaient que pour avoir du succès romantique avec ces femmes, ils devraient se conformer à un standard d,apparence idéalisée. La troisième étude a répliqué le résultat selon lequel l'exposition à des femmes sexuellement objectivées déclenchait la gêne et elle a, de plus, démontré que cet effet était médié par la confiance amoureuse. Abstract Die Rolle von Männermagazinen für das Priming von dauerhaften und vorübergehenden aussehensbezogenen Schemata bei Männern: Eine Untersuchung von Langzeit- und experimentellen Ergebnissen Wir präsentieren ein Forschungsprogramm, welches die Wirkung von Männermagazinen auf die Körperwahrnehmung von Männern und die Besorgnis um ihr Aussehen untersucht. Studie 1, basierend auf Panel-Daten von männlichen BA-Studierenden, zeigte, dass die Wahrnehmung von Männermagazinen im Jahr 1 die eigene Körperwahrnehmung im Jahr 2 vorhersagt. Studie 2 zeigte experimentell, dass Männer, die objektivierte Frauen in Männermagazinen vorgelegt bekamen, ein signifikant höheres Maß an Angst um ihr Aussehen und die aussehensbezogenen Motivationen für sportliche Aktivitäten angaben als Männer, die männliche Modemodelle sahen. Wir nehmen an, dass die Teilnehmer glaubten, dass sie sich diesem idealisierten Aussehensstandard angleichen müssen, um bei Frauen romantisch erfolgreich zu sein. Studie 3 replizierte die Ergebnisse, dass die Rezeption sexualisierter, objektivierter Frauen eine Körperselbstwahrnehmung primed - zudem wird dieser Effekt durch romantisches Vertrauen vermittelt. Resumen El Rol las Revistas de Muchachos en la Detonación en los Hombres de la Pauta Relacionada con la Apariencia Crónica y Temporaria: Una Investigación de Resultados Longitudinales y Experimentales Presentamos un programa de investigación que investiga los efectos de las revistas de muchachos sobre la auto consciencia del cuerpo del hombre y la ansiedad dada la apariencia. El estudio 1, que se basó en un panel de datos de estudiantes de grado masculinos, demostró que la exposición a una revista de muchachos en el año 1 predijo la auto consciencia del cuerpo en el año 2. El estudio 2 fue un experimento que mostró que los hombres asignados a ver mujeres objetivadas por las revistas de muchachos, reportaron niveles significativamente mayores de ansiedad de la apariencia y cosas relacionadas con la apariencia tales como motivación para hacer ejercicio, más que los hombres que fueron asignados a mirar moda de modelos masculinos. Especulamos que los participantes creyeron que para tener éxito, desde el punto de vista romántico con esas mujeres requiere conformar con la apariencia idealizada estándar. El estudio 3 replicó este hallazgo que la exposición a mujeres objetivadas detonó la auto consciencia sobre el cuerpo, y demostró más aún que el efecto fue mediado por la confianza romántica. ZhaiYao Yo yak [source]

    Effectiveness of Falls Clinics: An Evaluation of Outcomes and Client Adherence to Recommended Interventions

    JOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 4 2008
    Keith D. Hill PhD
    OBJECTIVES: To evaluate outcomes associated with falls clinic programs. DESIGN: Longitudinal. SETTING: Thirteen outpatient falls clinics in Victoria, Australia. PARTICIPANTS: Four hundred fifty-four people referred for clinic assessment (mean age±standard deviation 77.9±8.8; 73% female). INTERVENTION: After assessment, multifactorial interventions were organized to address identified risk factors. MEASUREMENTS: A Minimum Data Set was developed and used across all clinics to derive common data on falls, falls injuries, and secondary measures associated with falls risk, including balance, falls efficacy, gait, leg strength, function, and activity. All measures were repeated 6 months later. RESULTS: Clients had a high risk of falls, with 78% having had falls in the preceding 6 months (63% multiple fallers, 10% experiencing fractures from the falls). An average of 7.6±2.8 falls risk factors were identified per client. The clinic team organized an average of 5.7±2.3 new or additional interventions per client. Sixty-one percent of eligible clients returned for the 6-month assessment. At this time, there was more than a 50% reduction in falls, multiple falls, and fall injuries (P,.004) and small but significant improvements evident on secondary measures of balance, leg strength, gait speed, and confidence outcomes (P<.006). Average adherence to recommendations was 74.3%. Factors associated with higher adherence included being male, younger than 65, living with others, and having a caregiver (P<.05). CONCLUSION: This large multicenter study identified high falls risk of older people referred to falls clinics, the multifactorial nature of their presenting problems and provides preliminary evidence of positive outcomes after falls clinic management. [source]

    After Adoption: Sustaining the Innovation A Case Study of Disseminating the Hospital Elder Life Program

    JOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 9 2005
    Elizabeth H. Bradley PhD
    Objectives: To examine key factors that influence sustainability in the diffusion of the Hospital Elder Life Program (HELP) as an example of an evidence-based, multifaceted, innovative program to improve care for hospitalized older adults. Design: Longitudinal, qualitative study between November 2000 and November 2003 based on 102 in-depth interviews every 6 months during HELP implementation. Setting: Thirteen hospitals implementing HELP. Participants: Forty-two hospital staff members (physician, nursing, volunteer, and administrative staff) implementing HELP, conducted 102 interviews. Measurements: Staff experiences sustaining the program, including challenges and strategies that they viewed as successful in addressing these challenges. Results: Of the 13 hospitals studied, 10 were sustaining HELP at the end of the study period; three terminated the program (after 24 months, 12 months, and 6 months). Critical factors were identified as influencing whether the program was sustained: the presence of clinical leadership, the ability and willingness to adapt the original HELP protocols to local hospital circumstances and constraints, and the ability to obtain longer-term resources and funding for HELP. Conclusion: Recognizing the need for sustained clinical leadership and funding as well as the inevitable modifications required to sustain innovative programs can promote more-realistic goals and expectations for health services researchers, clinicians, and policy makers in their laudable efforts to translate research into practice. [source]

    Plasma Hypertonicity: Another Marker of Frailty?

    JOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 8 2004
    Jodi D. Stookey PhD
    Objectives: To determine whether plasma hypertonicity might be a marker of early frailty, this study tested the associations between plasma hypertonicity, incident disability, and mortality in nondisabled older adults. Design: Longitudinal, observational study. Setting: Community-based. Participants: Older adults (,70), who reported no disability and gave blood in the 1992 Duke Established Populations for Epidemiologic Studies of the Elderly survey (n=705), were re-interviewed in 1996 for functional status (n=561) and followed for all deaths up to January 1, 2000. Measurements: Plasma tonicity was estimated from plasma glucose, sodium, and potassium measures and used to classify subjects as normo- (285,294 mOsm/L) or hypertonic (,300 mOsm/L). Disability was defined as any impairment on the Rosow-Breslau, activity of daily living (ADL), and instrumental activity of daily living (IADL) scales. The relative risk (RR) of any new disability and relative hazard of death associated with hypertonicity were estimated using logistic regression models and Cox proportional hazards models, respectively. All models were controlled for age, sex, race, weight status, current smoking, activity level, plasma blood urea nitrogen and creatinine, cognitive impairment, depression, and chronic disease status. To determine whether observed effects were attributable to plasma glucose alone, all models were repeated on a subsample of nondiabetic, normoglycemic subjects. Results: Plasma hypertonicity (observed in 15% of subjects) was associated with increased risk of new Rosow-Breslau (RR=2.1, 95% confidence interval (CI)=1.2,3.6), IADL (RR=2.3, 95% CI=1.2,4.3), and ADL (RR=2.7 95% CI=1.3,5.6) disability by 1996 and mortality by 2000 (RR=1.4, 95% CI=1.0,1.9). Results were similar for the normoglycemic subgroup (ADL: RR=2.9, 95% CI=1.0,8.0; IADL: RR=2.5, 95% CI=1.0,6.3; Rosow-Breslau: RR=1.8, 95% CI=0.8,3.9; mortality: RR=1.5, 95% CI=0.9,2.3). Conclusion: Plasma hypertonicity may be a marker of early frailty. It was prevalent in this sample of nondisabled community-dwelling older adults and predicted incident disability and mortality. Further research to identify its determinants and consequences may help inform interventions against frailty. [source]

    Postpubertal Architectural Developmental Patterns Differ Between the L3 Vertebra and Proximal Tibia in Three Inbred Strains of Mice,

    JOURNAL OF BONE AND MINERAL RESEARCH, Issue 12 2008
    Helen R Buie
    Abstract An understanding of normal microarchitectural bone development patterns of common murine models is needed. Longitudinal, structural, and mineralization trends were evaluated by in vivo ,CT over 12 time points from 6,48 wk of age at the vertebra and tibia of C3H/HeN, C57BL/6, and BALB/C mice. Longitudinal growth occurred rapidly until 8,10 wk, slowed as the growth plate bridged, and fused at 8,10 mo. Structural augmentation occurred through formation of trabeculae at the growth plate and thickening of existing ones. In the vertebrae, BV/TV increased rapidly until 12 wk in all strains. Between 12 and 32 wk, the architecture was stable with BV/TV deviating <1.1%, 1.6%, and 3.4% for the C57BL/6, BALB/C, and C3H/HeN mice. In contrast, the tibial architecture changed continuously but more moderately for BV/TV and TbTh compared with the vertebra and with comparable or larger changes for TbN and TbSp. Age-related trabecular deterioration (decreased BV/TV and TbN; increased TbSp and structure model index) was evident at both sites at 32 wk. In all strains, the cortex continued to develop after trabecular values peaked. The temporal plateau of BMD was variable across mouse strains and site, whereas tissue mineral density was attained at ,6 mo for all sites and strains. Geometric changes at the tibial diaphysis occurred rapidly until 8,10 wk, providing the C57BL/6 mice and C3H/HeN mice with the highest torsional and compressive rigidity, respectively. In summary, key skeletal development milestones were identified, and architectural topology at the vertebra was found to be more stable than at the tibia. [source]

    The impact of a nurse-led support and education programme for spouses of stroke patients: a randomized controlled trial

    JOURNAL OF CLINICAL NURSING, Issue 8 2005
    Jenny Larson RN, PhD student
    Aims and objectives., The aim of the present study was to determine the impact of a nurse-led support and education programme for improving the spouses' perceived general quality of life, life situation, general well-being and health state. Background., Stroke is a disease with great consequences for the patients and their families. The spouses often feel obligated to care for the patient, providing psychological and physical support and having to cope with the patient's physical and cognitive impairments. This might lead to increased problems, as family members struggle to adapt to their new roles and responsibilities. Design and methods., Longitudinal, randomized controlled trial. One hundred spouses were randomly assigned to intervention or control groups, 50 in each group. The intervention group participated in a support and education programme, six times during six months, led by stroke specialist nurses. Both groups were followed for 12 months. Results., No significant differences were found, between intervention and control groups, over time. In the sub analyses, we found that the group attending 5,6 times had a significant decrease in negative well-being and increased quality of life over time, while the group attending fewer times had a significant decrease in positive well-being and health state, similar to the control group, which also had a significant decrease in negative and general well-being. Conclusions., A support and education programme might have a positive effect on spouses' well-being, on condition that they attend at least five times. Relevance to clinical practice., To facilitate the spouses' role as informal caregivers to the stroke patients, further development of the support and education programme used in the present study is needed, including empowerment approach and implementation of coping strategies. [source]

    Homocysteine, malondialdehyde and endothelial markers in dialysis patients during low-dose folinic acid therapy

    JOURNAL OF INTERNAL MEDICINE, Issue 5 2002
    T. Apeland
    Abstract. Apeland T, Mansoor MA, Seljeflot I, Brønstad I, Gøransson L, Strandjord RE (Rogaland Central Hospital, Stavanger; and Ullevål University Hospital, Oslo; Norway). Homocysteine, malondialdehyde and endothelial markers in dialysis patients during low-dose folinic acid therapy. J Intern Med 2002; 252: 456,464. Objectives. Haemodialysis patients have elevated levels of the atherogenic amino acid homocysteine. We wanted to assess the effects of small doses of intravenous folinic acid (the active form of folic acid) on some biochemical risk factors of cardiovascular disease. Design. Longitudinal and open intervention study. Setting. Two dialysis units in the County of Rogaland. Subjects. All patients on maintenance haemodialysis were invited, and 32 of 35 patients gave their informed consent. Interventions. After each dialysis session, the patients were given 1.0 mg of folinic acid intravenously thrice a week for a period of 3 months. Prior to and during the study, all patients were on maintenance supplementation with small doses of vitamins B1, B2, B3, B5, B6 and B12. Main outcome measures. Changes in the levels of (i) plasma total homocysteine (p-tHcy) and folate, (ii) circulating endothelium related proteins , markers of endothelial activation and (iii) serum malondialdehyde (S-MDA) , a marker of oxidative stress and lipid peroxidation. Results. The p-tHcy levels were reduced by 37% (P < 0.0001), whilst the serum and erythrocyte folate levels increased by 95 and 104%, respectively (P < 0.0001 for both). The circulating levels of endothelium related cellular adhesion molecules and haemostatic factors remained high and unchanged, except the thrombomodulin (TM) levels increased (P = 0.0004). The high levels of S-MDA were reduced by 26% (P = 0.003). Conclusions. Low doses of folinic acid given intravenously to dialysis patients reduced their levels of p-tHcy and S-MDA and thus improved their cardiovascular risk profile. The concurrent increment in TM levels was unexpected and of unknown clinical significance. [source]

    Stress Crossover in Newlywed Marriage: A Longitudinal and Dyadic Perspective

    JOURNAL OF MARRIAGE AND FAMILY, Issue 3 2007
    Lisa A. Neff
    Studies of stress and marital quality often assess stress as an intrapersonal phenomenon, examining how spouses' stress may influence their own relationship well-being. Yet spouses' stress also may influence partners' relationship evaluations, a phenomenon referred to as stress crossover. This study examined stress crossover, and conditions that may facilitate crossover, in a sample of 169 newlywed couples over 3.5 years. A significant crossover effect emerged for husbands, which was moderated by couples' observed conflict resolution skills. For wives, a significant stress interaction emerged, such that the influence of husbands' stress on wives' marital satisfaction depended on wives' own stress levels. These findings highlight the importance of a dyadic approach when examining the role of stress in marriage. [source]

    Longitudinal follow up of SIVmac pathogenesis in rhesus macaques of Chinese origin: emergence of B cell lymphoma

    JOURNAL OF MEDICAL PRIMATOLOGY, Issue 4-5 2002
    B. Ling
    Abstract: Two subspecies of rhesus (Rh) macaques, the Chinese (Ch) and Indian (Ind) subspecies were infected intravenously with 100TCID50 SIVmac239. CD4+, CD8+ T cells, plasma viral loads, depletion of intestinal lymphocytes with memory phenotype, humoral immune responses and clinical courses were monitored for 600 days. The pathogenesis of SIVmac was also compared with primary human immunodeficiency virus (HIV) infection of humans. Plasma viral loads in Ch Rh were lower in the acute and chronic phases compared with Ind Rh. SIVmac pathogenesis in Ch Rh was closer to virus loads in untreated HIV infected humans. Ch Rh had higher CD4/CD8 ratios, stronger antibody responses and interestingly, less depletion of intestinal memory CCR5+ CD4+ T lymphocytes compared with Ind Rh. One Ch Rh developed B cell origin lymphoma at 570 days post-infection, the first such report in this subspecies. Three of four Ind Rh developed AIDS within 6 months. The findings indicate that Ch Rh are more resistant to SIVmac pathogenesis compared with Ind Rh and that Ch Rh paralleled HIV-1 infections in untreated adult humans. The SIVmac infected Ch Rh subspecies are an acceptable model for HIV/AIDS. [source]

    Effects of Maternal Depressive Symptoms and Infant Gender on the Interactions Between Mothers and Their Medically At-Risk Infants

    JOURNAL OF OBSTETRIC, GYNECOLOGIC & NEONATAL NURSING, Issue 1 2008
    June Cho
    ABSTRACT Objective:, To examine the effects of maternal depressive symptoms and infant gender on interactions between mothers and medically at-risk infants. Design:, Longitudinal, descriptive secondary analysis. Setting:, Neonatal intensive care unit, intermediate care unit, and infectious disease clinic of the tertiary medical centers in the Southeast and East. Participants:, One hundred and eight preterm infants and their mothers, 67 medically fragile infants and their mothers, and 83 infants seropositive for HIV and their primary caregivers were studied in their homes between 6 and 24 months. Main Outcome Measures:, Observation and the Home Observation for Measurement of the Environment Inventory were used to assess the interactions of mothers and their medically at-risk infants. Maternal depressive symptoms were assessed using the Center for Epidemiologic Studies Depression Scale. Results:, The level of depressive symptoms did not differ between the mothers of boys and mothers of girls in the three groups. Mothers of medically fragile infants had higher levels of depressive symptoms than mothers of preterm infants at 6 months corrected age and similar levels of depressive symptoms as HIV-positive mothers at 12 months. Mothers of medically fragile infants with elevated depressive symptoms were less attentive and more restrictive to their infants. HIV-positive mothers with elevated depressive symptoms were less attentive to their infants. The effects of gender on mother-infant interactions were not moderated by maternal depressive symptoms. Conclusion:, Maternal depressive symptoms had a somewhat negative effect on the interactions of mothers and medically at-risk infants. [source]

    Quantitative mouse model of implant-associated osteomyelitis and the kinetics of microbial growth, osteolysis, and humoral immunity,

    JOURNAL OF ORTHOPAEDIC RESEARCH, Issue 1 2008
    Dan Li
    Abstract Although osteomyelitis (OM) remains a serious problem in orthopedics, progress has been limited by the absence of an in vivo model that can quantify the bacterial load, metabolic activity of the bacteria over time, immunity, and osteolysis. To overcome these obstacles, we developed a murine model of implant-associated OM in which a stainless steel pin is coated with Staphylococcus aureus and implanted transcortically through the tibial metaphysis. X-ray and micro-CT demonstrated concomitant osteolysis and reactive bone formation, which was evident by day 7. Histology confirmed all the hallmarks of implant-associated OM, namely: osteolysis, sequestrum formation, and involucrum of Gram-positive bacteria inside a biofilm within necrotic bone. Serology revealed that mice mount a protective humoral response that commences with an IgM response after 1 week, and converts to a specific IgG2b response against specific S. aureus proteins by day 11 postinfection. Real-time quantitative PCR (RTQ-PCR) for the S. aureus specific nuc gene determined that the peak bacterial load occurs 11 days postinfection. This coincidence of decreasing bacterial load with the generation of specific antibodies is suggestive of protective humoral immunity. Longitudinal in vivo bioluminescent imaging (BLI) of luxA-E transformed S. aureus (Xen29) combined with nuc RTQ-PCR demonstrated the exponential growth phase of the bacteria immediately following infection that peaks on day 4, and is followed by the biofilm growth phase at a significantly lower metabolic rate (p,<,0.05). Collectively, these studies demonstrate the first quantitative model of implant-associated OM that defines the kinetics of microbial growth, osteolysis, and humoral immunity following infection. © 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J. Orthop Res 26:96,105, 2008 [source]

    Financial Costs of Alcoholism Treatment Programs: A Longitudinal and Comparative Evaluation Among Four Specialized Centers

    ALCOHOLISM, Issue 1 2003
    B. Nalpas
    Background: Alcoholism is a worldwide problem. Many strategies for alcohol detoxification and relapse prevention exist, but each alcohol treatment center has its own program. The objective of this study was to analyze and compare the financial cost and effectiveness of alcohol treatment programs from inpatient stay to follow-up 1 year later. This was a prospective, open, nonrandomized study of 4 specialized alcohol treatment centers and 267 patients admitted for alcohol detoxification. Methods: We recorded all medical and nonmedical interventions related to the program during patient stay in the hospital and every 3 months after discharge for 1 year and recorded the occurrence of alcohol relapse. Financial evaluation was based on the prices of refund from the French national health insurance service. Results: The mean cost of hospitalization ranged from ,1326 to ,1917 (p= 0.001), a variation mainly due to the difference in the length of hospital stay but also to the cost of the inpatient program, routine medical checkups, and drugs administered. The mean cost of 1 year of follow-up per patient ranged from ,419 to ,1704 (p= 0.001). The efficiency, corresponding to the money spent to prevent the relapse of one patient during 1 month, was approximately ,500/month in three centers and ,658 in the fourth. However, for a similar efficiency, the effectiveness, assessed by the mean time without relapse, was significantly (p= 0.001) different; center 1, which had the highest total cost, had an effectiveness 1.56 times higher than center 3, which had the lowest cost. Conclusions: This work emphasizes the heterogeneity of the costs and effectiveness of alcoholism treatment programs and suggests that research should be conducted to determine which program is the most rational, cost-efficient, and beneficial for patients and the public health office economy. [source]

    Water spin dynamics during apoptotic cell death in glioma gene therapy probed by T1, and T2,

    MAGNETIC RESONANCE IN MEDICINE, Issue 6 2008
    A. Sierra
    Abstract Longitudinal and transverse relaxations in the rotating frame, with characteristic time constants T1, and T2,, respectively, have potential to provide unique MRI contrast in vivo. On-resonance spin-lock T1, with different spin-lock field strengths and adiabatic T2, with different radiofrequency-modulation functions were measured in BT4C gliomas treated with Herpes Simplex Virus thymidine kinase (HVS-tk) gene therapy causing apoptotic cell death. These NMR tools were able to discriminate different treatment responses in tumor tissue from day 4 onward. An equilibrium two-site exchange model was used to calculate intrinsic parameters describing changes in water dynamics. Observed changes included increased correlation time of water associated with macromolecules and a decreased fractional population of this pool. These results are consistent with destructive intracellular processes associated with cell death and the increase of extracellular space during the treatment. Furthermore, association between longer exchange correlation time and decreased pH during apoptosis is discussed. In this study, we demonstrated that T1, and T2, MR imaging are useful tools to quantify early changes in water dynamics reflecting treatment response during gene therapy. Magn Reson Med 59:1311,1319, 2008. © 2008 Wiley-Liss, Inc. [source]

    Longitudinal trends of total and allergen-specific IgE throughout childhood

    ALLERGY, Issue 7 2009
    P. M. Matricardi
    Background:, The development and the quantitative relationship between allergen-specific IgE (S-IgE) responses and total IgE (T-IgE), during childhood and adolescence have not been described and understood in detail. The objective of this study was to describe and compare the longitudinal trends of serum levels of S-IgE and T-IgE during childhood. Methods:, We analysed data from participants in the MAS birth cohort study at 2, 5, 7 and 10 years of age (n = 273) and at 1, 3, 5, 6, 7, 10 and 13 years (n = 84). Total-IgE and the overall level of specific-IgE against nine locally relevant airborne and food allergens were determined by FEIA (ImmunoCAP). Allergic rhino-conjunctivitis and asthma were ascertained by questionnaires. Results:, Longitudinal patterns of T-IgE levels from age 1 to 13 years were highly heterogeneous (declining, flat or increasing with different profiles). From 5 years of age, logarithmic (log10) transformed values of T-IgE and of S-IgE levels tend to follow a parallel trend, so that their relation remained constant throughout school age. A flat trend of T-IgE vs a constantly increasing trend of T-IgE was associated with a low or, respectively, high rate of wheezing at 13 years of age. Conclusions:, Beginning at the age of 5 years, total serum IgE levels in children from an industrialized country evolved in parallel with overall S-IgE levels. Therefore, variations in T-IgE levels at school age closely reflect variations in overall S-IgE levels. Further studies are required to strengthen the biological and clinical implication of this novel finding. [source]

    Longitudinal and Radial Gradients of PO2 in the Hamster Cheek Pouch Microcirculation

    MICROCIRCULATION, Issue 3 2008
    Helena Carvalho
    ABSTRACT Objectives: The aim of this study was to determine longitudinal and radial gradients in oxygen tension (PO2) in microvessels of the hamster cheek pouch. Methods: We measured PO2 using the phosphorescence-quenching method in two orders of arterioles (45.8 ± 5.5 and 19.9 ± 1.8 , m diameter), capillaries, and two orders of venules (50.5 ± 3.4 and 21.4 ± 2.0 , m diameter) in order to determine the longitudinal PO2 gradient. At the arteriolar and venular sites, we also measured PO2 at four different sites for an analysis of radial PO2 gradients: centerline, inside wall (larger arteriole and venule only), outside wall, and interstitium. We used 10 hamsters weighing 115 ± 27 g anesthetized with pentobarbital intraperitoneally and maintained with alpha-chloralose intravenously. The cheek pouch was everted and a single-layered preparation was studied by intravital microscopy. Albumin-bound Pd-porphyrin was infused into the circulation and excited by flash illumination at 10 Hz, with a rectangular diaphragm limiting the excitation field to 5 × 25 , m. Results: In the longitudinal direction, intravascular PO2 decreased significantly (P < 0.01) from large arterioles (39.5 ± 2.3 mmHg) to small arterioles (32.2 ± 0.3 mmHg), then to capillaries (30.2 ± 1.8 mmHg), and on to small venules (27.3 ± 2.1 mmHg) and large venules (25.5 ± 2.2 mmHg). In the radial direction, PO2 decreased significantly (P < 0.01) in and around larger arterioles, and to a lesser extent, around the smaller ones (P < 0.05). There was no significant PO2 gradient, longitudinal or radial, associated with venules. The PO2 difference from the centerline to the outside wall in large arterioles was 8.3 ± 1.4 mmHg, and most of the decline in PO2 in the radial direction was contributed by the intravascular difference (4.7 ± 2.1 mmHg) and only about 1.0 ± 2.7 mmHg by the transmural difference. Conclusions: Our data show that there are large intra-arteriolar radial PO2 gradients, but no large transmural PO2 differences, suggesting that the oxygen consumption of the microvessel wall is not exceptionally high. [source]

    A review of bilateral training for upper extremity hemiparesis

    OCCUPATIONAL THERAPY INTERNATIONAL, Issue 3-4 2009
    Mary Ellen Stoykov
    Abstract Upper extremity hemiparesis is the most common post-stroke disability. Longitudinal studies have indicated that 30,66% of stroke survivors do not have full arm function 6 months post-stroke. The current gold standard for treatment of mild post-stroke upper limb impairment is constraint-induced therapy but, because of the inclusion criteria, alternative treatments are needed which target more impaired subjects. Bilateral arm training has been investigated as a potential rehabilitation intervention. Bilateral arm training encompasses a number of methods including: (1) bilateral isokinematic training; (2) mirror therapy using bilateral training; (3) device-driven bilateral training; and (4) bilateral motor priming. Neural mechanisms mediating bilateral training are first reviewed. The key bilateral training studies that have demonstrated evidence of efficacy will then be discussed. Finally, conclusions are drawn concerning clinical implications based on the reviewed literature. Copyright © 2009 John Wiley & Sons, Ltd. [source]

    Contrasting longitudinal and cross-sectional relationships between insulin resistance and percentage of body fat, fitness, and physical activity in children,the LOOK study

    PEDIATRIC DIABETES, Issue 8 2009
    Richard D Telford
    Background: Knowledge of individual changes in insulin resistance (IR) and longitudinal relationships of IR with lifestyle-associated factors are of important practical significance, but little longitudinal data exist in asymptomatic children. We aimed to determine (a) changes in the homeostatic model of insulin resistance (HOMA-IR) over a 2-yr period and (b) comparisons of longitudinal and cross-sectional relationships between HOMA-IR and lifestyle-related risk factors. Methods: Our subjects, 241 boys and 257 girls, were assessed at age 8.1 yr (SD 0.35) and again 2 yr later for fasting blood glucose and insulin, dual X-ray absorptiometry-assessed percentage of body fat (%BF), pedometer-assessed physical activity (PA), and cardio-respiratory fitness (CRF) by multistage running test. Results: HOMA-IR was initially 9% greater in girls than boys and 27% greater 2 yr later. There was no evidence of longitudinal relationships between HOMA-IR and %BF in boys or girls, despite significant cross-sectional relationships (p < 0.001). In boys, there was evidence of a longitudinal relationship between HOMA-IR and both PA (p < 0.001) and CRF (p = 0.05). In girls, we found a cross-sectional relationship between HOMA-IR and CRF (p < 0.001). Conclusions: HOMA-IR increases between 8 and 10 yr of age and to a greater extent in girls. Longitudinal, unlike cross-sectional, relationships do not support the premise that body fat has any impact on HOMA-IR during this period or that PA or CRF changes affect HOMA-IR in girls. These data draw attention to difficulties in interpreting observational studies in young children. [source]

    Longitudinal and transverse incremental permeability of Co19.35Fe53.28Hf7.92O19.35 films

    PHYSICA STATUS SOLIDI (A) APPLICATIONS AND MATERIALS SCIENCE, Issue 12 2007
    Anh-Tuan Le
    Abstract We present here, the results of a thorough study of the longitudinal permeability ratio (LPR) and transverse permeability ratio (TPR) in sputtered Co19.35Fe53.28Hf7.92O19.35 films with varying thicknesses (t = 1, 1.5, 1.8 and 2.4 µm) in the frequency range of 100 - 1000 MHz. It is found that for all samples investigated, the LPR/TPR first increases with increasing frequency, reaches a maximum at 710 MHz, and then decreases at higher frequencies. This is related to the ferromagnetic resonance. The LPR and TPR profiles measured along the easy axis of the film show a single-peak feature, whereas those measured along the hard axis of the film show a double-peak one. This indicates an existence of magnetic anisotropy and its dispersion in the films. It reveals that the study of LPR and TPR spectra provides an alternative way for the evaluation of the high-frequency magnetic softness of film-type materials. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]

    Temperature dependence of elastic parameters and internal frictions for MnCu20Ni5Fe2 alloy

    PHYSICA STATUS SOLIDI (A) APPLICATIONS AND MATERIALS SCIENCE, Issue 3 2004
    Mikio Fukuhara
    Abstract Using ultrasonics, MnCu20Ni5Fe2 (M2052) alloy's acoustic characteristics were observed in order to understand its high damping properties. Longitudinal and shear wave velocities, eight kinds of elastic parameters, and dilational and shear internal frictions were simultaneously measured as functions of temperature in cooling and heating runs between 218 and 373 K in M2052 alloy. A valley in Young and shear moduli, Debye temperature and internal friction peaks at around 345 K showed a M2052 fcc/fct trans-formation, accompanied by volume-nonpreserving lattice softening. The increment of dilational friction in the low temperature can be interpreted as boundary effect of the misfit domain, associated with nonharmonity of potential between pairs of atoms. The M2052 alloy shows highest elasticity below 300 K, indicating large resistance for volume-preserving distortion. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]

    Transport in MgB2 near critical temperature

    PHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 9 2006
    P. Va
    Abstract Longitudinal and transverse voltages have been studied on samples of MgB2. The non-zero transverse voltage has been observed in close vicinity of critical temperature in zero external magnetic field while far enough from Tc this voltage has been zero. It merges into transverse even voltage in magnetic field which is suppressed with increasing field and increasing transport current as well. New scaling between transverse and longitudinal resistivities has been observed in the form ,xy , d,xx/dT. Several models trying to explain observed results are discussed. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]

    Assessment of fetal lung development by quantitative ultrasonic tissue characterization: a methodical study

    PRENATAL DIAGNOSIS, Issue 9 2004
    Ismail Tekesin
    Abstract Objectives This study was performed to evaluate the quantitative ultrasonic tissue characterization of the normal fetal lung development by using acoustic raw data captured after preprocessing. Methods One hundred and sixty-two patients with completed gestational ages between 22 and 37 weeks were enrolled in this study. Longitudinal and transverse sections of the fetal thorax and upper abdomen were imaged. A region of interest of constant size was defined and the tissue-specific gray scale was determined by using an interactive software. Results A total of 162 patients met the inclusion criteria. The echogenicity of the fetal lung showed a particular changing pattern during pregnancy: the mean gray value of the fetal lung (MGV) is almost the same as the MGV of the fetal liver at 22 and 23 weeks, decreases between 22 and 31 weeks and increases between 31 and 37 weeks. The MGV of the fetal liver decreases significantly from 24 weeks to 31 weeks and increases significantly again toward 37 weeks. We stated that the MGV of the lung is smaller than the MGV of the liver during 31 weeks of gestation and the relation reverses in late gestation. At term, the MGV of the liver is greater than the MGV of the lung. The lung-to-liver ratio is <1 between 24 and 29 weeks and >1 between 30 and 35 weeks. Conclusion The echogenicity of the fetal lung showed a particular changing pattern during pregnancy, which corresponds to morphologic changes of the fetal lung development. Copyright © 2004 John Wiley & Sons, Ltd. [source]

    Surveying Mobile Populations: Lessons from Recent Longitudinal Surveys of Indigenous Australians

    THE AUSTRALIAN ECONOMIC REVIEW, Issue 3 2002
    B. H. Hunter
    Geographically mobile populations are notoriously difficult to survey, especially in a cross,cultural context. In broad terms, it is difficult to ensure that respondents are representative of the underlying population, can be relocated, and that data obtained are relevant to them. At a practical level, the problem can be as basic as not having any well,formed notion of what defines a household. Consequently, the resulting analysis of households is at best imprecise and, at worst, conceptually confused. This article documents the lessons for the design and conduct of longitudinal data collection from three recent surveys of an exceptionally mobile population, Indigenous Australians. There appears to be a trade,off between cultural relevance, data quality, response rates and survey costs. The use of Indigenous interviewers does not, in itself, guarantee that response rates will be acceptable. [source]

    Multiple-Imputation-Based Residuals and Diagnostic Plots for Joint Models of Longitudinal and Survival Outcomes

    BIOMETRICS, Issue 1 2010
    Dimitris Rizopoulos
    Summary The majority of the statistical literature for the joint modeling of longitudinal and time-to-event data has focused on the development of models that aim at capturing specific aspects of the motivating case studies. However, little attention has been given to the development of diagnostic and model-assessment tools. The main difficulty in using standard model diagnostics in joint models is the nonrandom dropout in the longitudinal outcome caused by the occurrence of events. In particular, the reference distribution of statistics, such as the residuals, in missing data settings is not directly available and complex calculations are required to derive it. In this article, we propose a multiple-imputation-based approach for creating multiple versions of the completed data set under the assumed joint model. Residuals and diagnostic plots for the complete data model can then be calculated based on these imputed data sets. Our proposals are exemplified using two real data sets. [source]

    A Semiparametric Joint Model for Longitudinal and Survival Data with Application to Hemodialysis Study

    BIOMETRICS, Issue 3 2009
    Liang Li
    Summary In many longitudinal clinical studies, the level and progression rate of repeatedly measured biomarkers on each subject quantify the severity of the disease and that subject's susceptibility to progression of the disease. It is of scientific and clinical interest to relate such quantities to a later time-to-event clinical endpoint such as patient survival. This is usually done with a shared parameter model. In such models, the longitudinal biomarker data and the survival outcome of each subject are assumed to be conditionally independent given subject-level severity or susceptibility (also called frailty in statistical terms). In this article, we study the case where the conditional distribution of longitudinal data is modeled by a linear mixed-effect model, and the conditional distribution of the survival data is given by a Cox proportional hazard model. We allow unknown regression coefficients and time-dependent covariates in both models. The proposed estimators are maximizers of an exact correction to the joint log likelihood with the frailties eliminated as nuisance parameters, an idea that originated from correction of covariate measurement error in measurement error models. The corrected joint log likelihood is shown to be asymptotically concave and leads to consistent and asymptotically normal estimators. Unlike most published methods for joint modeling, the proposed estimation procedure does not rely on distributional assumptions of the frailties. The proposed method was studied in simulations and applied to a data set from the Hemodialysis Study. [source]

    Joint Models for Multivariate Longitudinal and Multivariate Survival Data

    BIOMETRICS, Issue 2 2006
    Yueh-Yun Chi
    Summary Joint modeling of longitudinal and survival data is becoming increasingly essential in most cancer and AIDS clinical trials. We propose a likelihood approach to extend both longitudinal and survival components to be multidimensional. A multivariate mixed effects model is presented to explicitly capture two different sources of dependence among longitudinal measures over time as well as dependence between different variables. For the survival component of the joint model, we introduce a shared frailty, which is assumed to have a positive stable distribution, to induce correlation between failure times. The proposed marginal univariate survival model, which accommodates both zero and nonzero cure fractions for the time to event, is then applied to each marginal survival function. The proposed multivariate survival model has a proportional hazards structure for the population hazard, conditionally as well as marginally, when the baseline covariates are specified through a specific mechanism. In addition, the model is capable of dealing with survival functions with different cure rate structures. The methodology is specifically applied to the International Breast Cancer Study Group (IBCSG) trial to investigate the relationship between quality of life, disease-free survival, and overall survival. [source]

    Diagnostics for Joint Longitudinal and Dropout Time Modeling

    BIOMETRICS, Issue 4 2003
    Angela Dobson
    Summary. We present a variety of informal graphical procedures for diagnostic assessment of joint models for longitudinal and dropout time data. A random effects approach for Gaussian responses and proportional hazards dropout time is assumed. We consider preliminary assessment of dropout classification categories based on residuals following a standard longitudinal data analysis with no allowance for informative dropout. Residual properties conditional upon dropout information are discussed and case influence is considered. The proposed methods do not require computationally intensive methods over and above those used to fit the proposed model. A longitudinal trial into the treatment of schizophrenia is used to illustrate the suggestions. [source]

    A Bayesian Semiparametric Joint Hierarchical Model for Longitudinal and Survival Data

    BIOMETRICS, Issue 2 2003
    Elizabeth R. Brown
    Summary This article proposes a new semiparametric Bayesian hierarchical model for the joint modeling of longitudinal and survival data. We relax the distributional assumptions for the longitudinal model using Dirichlet process priors on the parameters defining the longitudinal model. The resulting posterior distribution of the longitudinal parameters is free of parametric constraints, resulting in more robust estimates. This type of approach is becoming increasingly essential in many applications, such as HIV and cancer vaccine trials, where patients' responses are highly diverse and may not be easily modeled with known distributions. An example will be presented from a clinical trial of a cancer vaccine where the survival outcome is time to recurrence of a tumor. Immunologic measures believed to be predictive of tumor recurrence were taken repeatedly during follow-up. We will present an analysis of this data using our new semiparametric Bayesian hierarchical joint modeling methodology to determine the association of these longitudinal immunologic measures with time to tumor recurrence. [source]

    Long-term effects of growth hormone (GH) treatment on body composition and bone mineral density in short children born small-for-gestational-age: six-year follow-up of a randomized controlled GH trial

    CLINICAL ENDOCRINOLOGY, Issue 4 2007
    Ruben H. Willemsen
    Summary Context, Alterations in the GH-IGF-I axis in short small-for-gestational-age (SGA) children might be associated with abnormalities in bone mineral density (BMD) and body composition. In addition, birth weight has been inversely associated with diabetes and cardiovascular disease in adult life. Data on detailed body composition in short SGA children and long-term effects of GH treatment are very scarce. Objective, To investigate effects of long-term GH treatment on body composition and BMD by dual energy X-ray absorptiometry (DXA) in short SGA children. Design, Longitudinal 6-year GH study with a randomized controlled part for 3 years. Results, At baseline, fat percentage standard deviation score (SDS) and lumbar spine BMD SDS corrected for height (BMADLS SDS) were significantly lower than zero. Lean body mass (LBM) SDS adjusted for age was also reduced, but LBM adjusted for height (LBM SDSheight) was not decreased. GH treatment induced a decrease in fat percentage SDS and an increase in BMADLS SDS. LBM SDSheight remained similar in GH-treated children, but deteriorated in untreated controls. When these untreated controls subsequently started GH treatment, their LBM SDSheight rapidly normalized to values comparable with zero. Conclusion, During long-term GH treatment in short SGA children, fat percentage SDS decreased and BMADLS SDS increased. These effects of GH treatment were most prominent in children who started treatment at a younger age and in those with greater height gain during GH treatment. LBM SDSheight remained around 0 SDS in GH-treated children, but declined to low normal values in untreated controls. [source]