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Significant Mechanism (significant + mechanism)
Selected AbstractsEffect of Normal Saline Infusion on the Diagnostic Utility of Base Deficit in Identifying Major Injury in Trauma PatientsACADEMIC EMERGENCY MEDICINE, Issue 12 2006Richard Sinert DO Abstract Background Base deficit (BD) is a reliable marker of metabolic acidosis and is useful in gauging hemorrhage after trauma. Resuscitation with chloride-rich solutions such as normal saline (NS) can cause a dilutional acidosis, possibly confounding the interpretation of BD. Objectives To test the diagnostic utility of BD in distinguishing minor from major injury after administration of NS. Methods This was a prospective observational study at a Level 1 trauma center. The authors enrolled patients with significant mechanism of injury and measured BD at triage (BD-0) and at four hours after triage (BD-4). Major injury was defined by any of the following: injury severity score of ,15, drop in hematocrit of ,10 points, or the patient requiring a blood transfusion. Patients were divided into a low-volume (NS < 2L) and a high-volume (NS , 2L) group. Data were reported as mean (±SD). Student's t- and Wilcoxon tests were used to compare data. Receiver operating characteristic (ROC) curves tested the utility of BD-4 in differentiating minor from major injury in the study groups. Results Four hundred eighty-nine trauma patients (mean age, 36 [± 18] yr) were enrolled; 82% were male, and 34% had penetrating injury. Major-(20%) compared with minor-(80%) injury patients were significantly (p = 0.0001) more acidotic (BD-0 mean difference: ,3.3 mmol/L; 95% confidence interval [CI] =,2.5 to ,4.2). The high-volume group (n = 174) received 3,342 (±1,821) mL, and the low-volume group (n = 315) received 621 (±509) mL of NS. Areas under the ROC curves for the high-volume (0.63; 95% CI = 0.52 to 0.74) and low-volume (0.73; 95% CI = 0.60 to 0.86) groups were not significantly different from each other. Conclusions Base deficit was able to distinguish minor from major injury after four hours of resuscitation, irrespective of the volume of NS infused. [source] The Risk of Intra-abdominal Injuries in Pediatric Patients with Stable Blunt Abdominal Trauma and Negative Abdominal Computed TomographyACADEMIC EMERGENCY MEDICINE, Issue 5 2010Jeffrey Hom MD Abstract Objectives:, This review examines the prevalence of intra-abdominal injuries (IAI) and the negative predictive value (NPV) of an abdominal computed tomography (CT) in children who present with blunt abdominal trauma. Methods:, MEDLINE, EMBASE, and Cochrane Library databases were searched. Studies were selected if they enrolled children with blunt abdominal trauma from the emergency department (ED) with significant mechanism of injury requiring an abdominal CT. The primary outcome measure was the rate of IAI in patients with negative initial abdominal CT. The secondary outcome measure was the number of laparotomies, angiographic embolizations, or repeat abdominal CTs in those with negative initial abdominal CTs. Results:, Three studies met the inclusion criteria, comprising a total of 2,596 patients. The overall rate of IAI after a negative abdominal CT was 0.19% (95% confidence interval [CI] = 0.08% to 0.44%). The overall NPV of abdominal CT was 99.8% (95% CI = 99.6% to 99.9%). There were five patients (0.19%, 95% CI = 0.08% to 0.45%) who required additional intervention despite their initial negative CTs: one therapeutic laparotomy for bowel rupture, one diagnostic laparotomy for mesenteric hematoma and serosal tear, and three repeat abdominal CTs (one splenic and two renal injuries). None of the patients in the latter group required surgery or blood transfusion. Conclusions:, The rate of IAI after blunt abdominal trauma with negative CT in children is low. Abdominal CT has a high NPV. The review shows that it might be safe to discharge a stable child home after a negative abdominal CT. ACADEMIC EMERGENCY MEDICINE 2010; 17:469,475 © 2010 by the Society for Academic Emergency Medicine [source] The Impact of Competing Goals, Experience, and Litigation Consciousness on Auditors' JudgmentsINTERNATIONAL JOURNAL OF AUDITING, Issue 3 2009Stephen K. Asare This study uses an experiment to examine the interactive effect of goals and experience on auditors' inventory write-off assessments and the role of litigation consciousness in mediating this effect. We find that when presented with a competing compliance and client relations goal, more experienced auditors were more likely to recommend an inventory write-off than less experienced auditors. However, when presented with only a compliance goal, auditors were equally likely to recommend an inventory write-off. The finding that less experienced auditors are more influenced by client relations goals suggests that the early socialization into the profession may be dominated by client relations concerns rather than litigation concerns. Mediation results suggest that auditors' litigation consciousness is a significant mechanism which helps drive the interactive effect of goals and experience on auditors' inventory write-off assessments. Implications for research, practice, and regulation are discussed. [source] SEXUAL REPRODUCTION, MATING SYSTEM, AND PROTOPLAST DYNAMICS OF SEMINAVIS (BACILLARIOPHYCEAE)1JOURNAL OF PHYCOLOGY, Issue 5 2002Victor A. Chepurnov Cell division, the mating system, and auxosporulation were studied in the marine epipelic diatom Seminavis cf. robusta Danielidis & D. G. Mann. The interphase protoplast contains two girdle-appressed chloroplasts, each with an elongate bar-like pyrenoid, and also a central nucleus, located in a bridge between two vacuoles. Before cell division, the chloroplasts divide transversely and translocate onto the valves. The nucleus relocates to the ventral side for mitosis. After cytokinesis and valve formation, the chloroplasts move back to the girdle, showing a constant clockwise movement relative to the epitheca of the daughter cell. Seminavis cf. robusta is dioecious, and sexual reproduction is possible once cells are less than 50 ,m. In crosses of compatible clones, gametangia pair laterally, without the formation of a copulation envelope, and produce two gametes apiece. The intensity of sexualization increases as cells reduce further in size below the 50-,m threshold. At plasmogamy, the gametangia dehisce fully and the gametes, which were morphologically and behaviorally isogamous, fuse in the space between the gametangial thecae. The auxospore forms a transverse and longitudinal perizonium. After expansion is complete, there is an unequal contraction of the protoplast within the perizonium, creating the asymmetrical shape of the vegetative cell. Apart from this last feature, almost all characteristics exhibited by the live cell and auxospores of Seminavis agree with what is found in Navicula sensu stricto, supporting the classification of both in the Naviculaceae. Haploid parthenogenesis and polyploid auxospores were found, lending support to the view that change in ploidy may be a significant mechanism in diatom evolution. [source] Ion channel formation and membrane-linked pathologies of misfolded hydrophobic proteins: The role of dangerous unchaperoned moleculesCLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY, Issue 9 2002Joseph I Kourie Summary 1.,Protein,membrane interaction includes the interaction of proteins with intrinsic receptors and ion transport pathways and with membrane lipids. Several hypothetical interaction models have been reported for peptide-induced membrane destabilization, including hydrophobic clustering, electrostatic interaction, electrostatic followed by hydrophobic interaction, wedge × type incorporation and hydrophobic mismatch. 2.,The present review focuses on the hypothesis of protein interaction with lipid membranes of those unchaperoned positively charged and misfolded proteins that have hydrophobic regions. We advance the hypothesis that protein misfolding that leads to the exposure of hydrophobic regions of proteins renders them potentially cytotoxic. Such proteins include prion, amyloid , protein (A,P), amylin, calcitonin, serum amyloid and C-type natriuretic peptides. These proteins have the ability to interact with lipid membranes, thereby inducing membrane damage and cell malfunction. 3.,We propose that the most significant mechanism of membrane damage induced by hydrophobic misfolded proteins is mediated via the formation of ion channels. The hydrophobicity based toxicity of several proteins linked to neurodegenerative pathologies is similar to those observed for antibacterial toxins and viral proteins. 4.,It is hypothesized that the membrane damage induced by amyloids, antibacterial toxins and viral proteins represents a common mechanism for cell malfunction, which underlies the associated pathologies and cytotoxicity of such proteins. [source] Prevalence of AmpC over-expression in bloodstream isolates of Pseudomonas aeruginosaCLINICAL MICROBIOLOGY AND INFECTION, Issue 4 2007V. H. Tam Abstract This study examined the contribution of AmpC over-expression to ,-lactam resistance in clinical isolates of Pseudomonas aeruginosa obtained from a hospital in Houston, TX, USA. Seventy-six non-repeat bloodstream isolates obtained during 2003 were screened for ceftazidime resistance in the presence and absence of clavulanic acid 4 mg/L. AmpC was identified by isoelectric focusing (with and without cloxacillin inhibition); stable derepression was ascertained phenotypically by a spectrophotometric assay (with and without preceding induction by imipenem) using nitrocefin as the substrate, and was confirmed subsequently by quantitative RT-PCR of the ampC gene. The clonal relatedness of the AmpC-over-expressing isolates was assessed by pulsed-field gel electrophoresis. In addition, the ampC and ampR gene sequences were determined by PCR and sequencing. For comparison, two standard wild-type strains (PAO1 and ATCC 27853) and three multidrug-susceptible isolates were used as controls. AmpC over-expression was confirmed in 14 ceftazidime-resistant isolates (overall prevalence rate, 18.4%), belonging to seven distinct clones. The most prevalent point mutations in ampC were G27D, V205L and G391A. Point mutations in ampR were also detected in eight ceftazidime-resistant isolates. AmpC over-expression appears to be a significant mechanism of ,-lactam resistance in P. aeruginosa. Understanding the prevalence and mechanisms of ,-lactam resistance in P. aeruginosa may guide the choice of empirical therapy for nosocomial infections in hospitals. [source] Pathways mediating sexual abuse and eating disturbance in childrenINTERNATIONAL JOURNAL OF EATING DISORDERS, Issue 3 2001Stephen Wonderlich Abstract Objective To examine the relationship between childhood maltreatment and eating disorders in a sample of children. Method Twenty 10,15-year-old female children who were receiving treatment following reported childhood sexual abuse and 20 age-matched controls were compared on a series of measures assessing eating disorder behaviors, body image concerns, substance use, mood, impulsive behavior, and self-concept. Results Sexually abused children reported higher levels of eating disorder behaviors, impulsive behaviors, and drug abuse than controls. Furthermore, behavioral impulsivity provided the strongest mediational effect between a history of childhood sexual abuse and purging and restrictive dieting behavior. Drug use proved to be a significant secondary mediator of the childhood sexual abuse eating disorder behavior association. Discussion These data support the hypothesis that childhood sexual abuse is related to disordered eating in children, and extend similar findings that have been previously reported with adults. Behavioral impulsivity and drug use appear to be significant mechanisms that influence eating disorder behavior following childhood sexual abuse. © 2001 by John Wiley & Sons, Inc. Int J Eat Disord 29: 270,279, 2001. [source] | ||||||||||