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Equivocal Results (equivocal + result)
Selected AbstractsThe effects of Panax ginseng on quality of lifeJOURNAL OF CLINICAL PHARMACY & THERAPEUTICS, Issue 1 2003C. I. Coleman Pharm D SummaryPanax ginseng is marketed and used to maintain natural energy, increase mental and physical abilities, improve mood and promote general health and well-being. Panax ginseng has been studied in a number of randomized clinical trials investigating its effect on physical and psychomotor performance, cognitive function, immunomodulation, diabetes mellitus and herpes simples type-II infections. Equivocal results have been demonstrated for many of these indications. P. ginseng is also commonly used to promote quality of life (QoL). As a result, ginseng's effect on QoL has become an increasingly important endpoint in clinical trials. We reviewed all studies (n = 9) that determined the effect of P. ginseng on QoL. P. ginseng's has been evaluated at dosages of 80,400 mg. Study duration has spanned from 2 to 9 months. Several QoL measures have been used, ranging from widely accepted core instruments to unpublished investigator-derived questionnaires. In addition, many of the investigators utilized ginseng extracts that were supplemented with vitamins and minerals while others used only standardized ginseng extract. Populations evaluated also differed in terms of underlying morbidity. Nearly every study evaluated (n = 8) demonstrated some degree of QoL improvement. Beneficial effects were evident within instrument summary component scores but improvement in overall composite scores of QoL was rarely seen. However, findings were equivocal. While populations evaluated varied in terms of underlying morbidity, there did not appear to be a substantial difference in their response to ginseng with respect to QoL. Despite some positive results, improvement in overall health-related quality of life cannot, given the current research, be attributed to P. ginseng. However, the possibility that various facets of QoL may have improved and the potential of early transient effects cannot be discounted. [source] Use of a functional assay to diagnose protein S deficiency; inappropriate testing yields equivocal resultsINTERNAL MEDICINE JOURNAL, Issue 6 2007A. M. Johnston Abstract Inherited deficiency of protein S (PS) is a rare but accepted risk factor for venous thromboembolism. There is accumulating evidence that inherited PS deficiency may be associated with a variety of adverse obstetric events. Acquired PS deficiency may be caused by a variety of clinical states including normal pregnancy. We conducted a retrospective audit of the results of screening for PS deficiency through our reference laboratory. The majority of patients in this audit with significantly reduced (<50%) free functional PS levels had a major confounding factor likely to cause acquired PS deficiency, most frequently pregnancy. Recommendations for PS testing for the diagnosis of hereditary PS deficiency include deferring testing until at least 40 days post-partum. It appears that these recommendations are not being adhered to leading to difficulty in the interpretation of results. [source] Within night correlations between radar and ground counts of migrating songbirdsJOURNAL OF FIELD ORNITHOLOGY, Issue 2 2008Michael L. Peckford ABSTRACT Studies comparing numbers of nocturnal migrants in flight with numbers of migrants at stopover sites have produced equivocal results. In 2003, we compared numbers of nocturnal migrants detected by radar to numbers of passerines observed at the Atlantic Bird Observatory in southwestern Nova Scotia, Canada. Numbers of nocturnal migrants detected by radar were positively correlated with numbers of migrants as determined by mist-netting, censuses, and daily estimated totals (daily estimates of birds present based netting and census results and casual observations) the following day. On nights with winds favorable for migration (tailwinds), the peak correlation between ground counts and radar counts the night before occurred just after sunset. On nights with unfavorable winds (headwinds), the correlation increased through the night, with a peak just before sunrise. The patterns of correlation are consistent with a scenario where birds accumulate at the coastline during periods of unfavorable wind, likely because they are not willing to cross a major ecological barrier, the Gulf of Maine. On nights with favorable winds, many birds departed, but some, possibly after testing wind conditions, apparently decided not to cross the Gulf of Maine and returned. Our results suggest that combining data collected using different methods to generate a daily estimated total provides the best estimate of the number of migrants present at a stopover site. Simultaneous studies at multiple locations where different census methods are used, making more effective use of temporal data (both from radar and diurnal counts), will more clearly elucidate patterns of flight behavior by migratory songbirds and the relationship between ground counts and counts of birds aloft. SINOPSIS Estudios cuales comparan los números de aves migratorias en vuelo durante la noche con los números de aves migratorias en sitios de reposo han producido resultados desiguales. En el 2003, comparamos los números de aves migratorias nocturnas detectadas por radar con los números de aves de Passeriformes observadas en el Atlantic Bird Observatory en el sudoeste de Nueva Escocia, Canadá. Los números de aves migratorias detectadas por radar fueron positivamente correlacionados con los números de aves migratorias detectadas mediante la captura con redes de neblina, por censos y por estimaciones diarias totales (el número de aves migratorias basado en capturas, censos y observaciones no-estandarizadas) durante el próximo día. En noches con vientos favorables para la migración (vientos de cola), el punto máximo de la correlación entre los conteos hechos en la tierra con los conteos hechas mediante radar durante la noche anterior ocurrió justo después de la puesta del sol. En noches con vientos no-favorables para la migración (vientos de frente), la correlación incrementó durante la noche, con un punto máximo justo antes del amanecer. Los patrones de las correlaciones son consistentes con una situación en la cual las aves se acumulan sobre la costa del mar durante periodos de viento no-favorables, probablemente porque no están dispuestos a cruzar una barrera ecológica de mayor tamaño, cual es el Golfo de Maine. En noches con vientos favorables, muchas aves partieron, pero algunos, posiblemente después de probar las condiciones de viento, aparentemente decidieron no cruzar el Golfo de Maine y retornaron. Nuestros resultados sugieren que una combinación de datos colectados utilizando diferentes métodos para generar una estimación diaria total provee la mejor estimación del número de aves migratorias presentes en un sitio de reposo. Estudios simultáneos hechos en múltiples sitios donde diferentes métodos de censo son utilizados, realizando un uso mas efectivo de los datos tomados a través del tiempo (provenientes de conteos mediante radar así como de observadores durante el día), mostrarán mas claramente cuales son los patrones del vuelo de las aves migratorias y la relación entre los conteos hechos en la tierra y los conteos de aves en alto vuelo. [source] The Moderating Effect of CEO Power on the Board Composition,Firm Performance Relationship*JOURNAL OF MANAGEMENT STUDIES, Issue 8 2007James G. Combs abstract Prior studies of the relationship between the composition of boards of directors and firm performance offer equivocal results. Drawing on agency and power circulation theories, we attempt to reduce this equivocality by asserting that CEO power moderates the relationship. Specifically, an outside director dominated board is needed to check a powerful CEO, but monitoring by other executives provides sufficient constraints on CEOs with low power. We used event study methodology to test the effects of the interaction between board composition and CEO power on stock market reaction to 73 unexpected CEO deaths. We found support for our theorizing among two of three sources of CEO power. Thus, although regulatory trends increasingly support outside director dominated boards, our findings indicate that this may not always benefit shareholders and that CEO power should be considered when constructing boards. [source] Persistence of a plasma melatonin rhythm in constant darkness and its inhibition by constant light in the sleepy lizard, Tiliqua rugosaJOURNAL OF PINEAL RESEARCH, Issue 1 2006Bruce T. Firth Abstract:, This study determined whether a blood plasma melatonin rhythm persists in constant photothermal environments in the sleepy lizard, Tiliqua rugosa. It builds upon an earlier investigation which provided equivocal results as to whether an in vivo melatonin rhythm persists in constant dark (DD) and light (LL) and temperature in this species. Using more frequent sampling points and new assay techniques, the present study showed that the melatonin rhythm persisted for at least 6 days at temperatures of 25 and 33°C in constant dark (DD). The melatonin rhythm, however, was largely eliminated in constant light (LL) at 33°C, thereby contradicting some previous findings in other species of reptiles where melatonin levels were apparently insensitive to an unexpected pulse of light at night. These results demonstrate that the sleepy lizard has a persistent, possibly circadian rhythm of melatonin in DD and constant temperature, and that the rhythm is inhibited by LL and constant temperature. Therefore, the sleepy lizard pineal gland may be an independent oscillator capable of driving the melatonin rhythm and be a transducer of the seasonally changing external photothermal environment. [source] Density compensation in New World bat communitiesOIKOS, Issue 2 2000Richard D. Stevens Understanding the role of competitive interactions in shaping the structure of communities has been one the most unrelenting challenges to ecology. Traditionally, competitive interactions were assumed to be the most important agent of deterministic structure, with overdispersed morphological patterns based on body size and trophic status as their hallmark. However, models of community organization based solely on morphology have yielded only equivocal results for many taxa. Fortunately, morphological patterns may not be the only indications of competitively induced deterministic structure. Herein, we explore the degree to which the structure of five feeding guilds (aerial insectivores, frugivores, gleaning animalivores, molossid insectivores, and nectarivores) from 15 New World bat communities reflects density compensation. Nonrandom associations between abundance and morphological distance were detected in five communities, in three feeding guilds, and with respect to four competitive scenarios. Nonetheless, patterns consistent with the hypothesis of density compensation were neither pervasive nor consistent in New World bat communities. Competitively induced community structure may exist under only narrow temporal and environmental conditions, and may not be characteristic of organization in most situations. [source] A NEW TITANOSAUR FROM WESTERN SÃO PAULO STATE, UPPER CRETACEOUS BAURU GROUP, SOUTH-EAST BRAZILPALAEONTOLOGY, Issue 1 2006RODRIGO MILONI SANTUCCI Abstract:, Material from a new titanosaur from the Bauru Basin (Bauru Group), Brazil is described and compared with well-known titanosaurs. Adamantisaurus mezzalirai gen. et sp. nov. is based on six articulated anterior caudal vertebrae and two haemapophyses collected from the Adamantina Formation, which is considered to be Campanian,Maastrichtian? in age. Adamantisaurus mezzalirai is characterized by the following combination of characteristics: anterior caudal vertebrae with straight or slightly backwardly-projecting neural spines with strongly expanded distal ends, stout prespinal lamina, very wide pre- and postzygapophyseal articular facets, and concave postzygapophyseal articular facets on anterior caudal vertebrae. Although our cladistic analysis has produced equivocal results, Adamantisaurus mezzalirai shares with DGM ,Series B' (Peirópolis titanosaur) and Aeolosaurus the presence of postzygapophyses with concave articular facets, and shares with DGM ,Series B' the presence of laterally expanded neural spines and stout prespinal lamina. Additionally, A. mezzalirai shares with DGM ,Series' C (other titanosaur from Peirópolis) the presence of short neural spines. [source] The Plant's Capacity in Regulating Resource DemandPLANT BIOLOGY, Issue 6 2005R. Matyssek Abstract: Regulation of resource allocation in plants is the key to integrate understanding of metabolism and resource flux across the whole plant. The challenge is to understand trade-offs as plants balance allocation between different and conflicting demands, e.g., for staying competitive with neighbours and ensuring defence against parasites. Related hypothesis evaluation can, however, produce equivocal results. Overcoming deficits in understanding underlying mechanisms is achieved through integrated experimentation and modelling the various spatio-temporal scaling levels, from genetic control and cell metabolism towards resource flux at the stand level. An integrated, interdisciplinary research concept on herbaceous and woody plants and its outcome to date are used, while drawing attention to currently available knowledge. This assessment is based on resource allocation as driven through plant-pathogen and plant-mycorrhizosphere interaction, as well as competition with neighbouring plants in stands, conceiving such biotic interactions as a "unity" in the control of allocation. Biotic interaction may diminish or foster effects of abiotic stress on allocation, as changes in allocation do not necessarily result from metabolic re-adjustment but may obey allometric rules during ontogeny. Focus is required on host-pathogen interaction under variable resource supply and disturbance, including effects of competition and mycorrhization. Cost/benefit relationships in balancing resource investments versus gains turned out to be fundamental in quantifying competitiveness when related to the space, which is subject to competitive resource exploitation. A space-related view of defence as a form of prevention of decline in competitiveness may promote conversion of resource turnover across the different kinds of biotic interaction, given their capacity in jointly controlling whole plant resource allocation. [source] A global phylogeny of apple snails: Gondwanan origin, generic relationships, and the influence of outgroup choice (Caenogastropoda: Ampullariidae)BIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 1 2009KENNETH A. HAYES Apple snails (Ampullariidae) are a diverse family of pantropical freshwater snails and an important evolutionary link to the common ancestor of the largest group of living gastropods, the Caenogastropoda. A clear understanding of relationships within the Ampullariidae, and identification of their sister taxon, is therefore important for interpreting gastropod evolution in general. Unfortunately, the overall pattern has been clouded by confused systematics within the family and equivocal results regarding the family's sister group relationships. To clarify the relationships among ampullariid genera and to evaluate the influence of including or excluding possible sister taxa, we used data from five genes, three nuclear and two mitochondrial, from representatives of all nine extant ampullariid genera, and species of Viviparidae, Cyclophoridae, and Campanilidae, to reconstruct the phylogeny of apple snails, and determine their affinities to these possible sister groups. The results obtained indicate that the Old and New World ampullariids are reciprocally monophyletic with probable Gondwanan origins. All four Old World genera, Afropomus, Saulea, Pila, and Lanistes, were recovered as monophyletic, but only Asolene, Felipponea, and Pomella were monophyletic among the five New World genera, with Marisa paraphyletic and Pomacea polyphyletic. Estimates of divergence times among New World taxa suggest that diversification began shortly after the separation of Africa and South America and has probably been influenced by hydrogeological events over the last 90 Myr. The sister group of the Ampullariidae remains unresolved, but analyses omitting certain outgroup taxa suggest the need for dense taxonomic sampling to increase phylogenetic accuracy within the ingroup. The results obtained also indicate that defining the sister group of the Ampullariidae and clarifying relationships among basal caenogastropods will require increased taxon sampling within these four families, and synthesis of both morphological and molecular data. © 2009 The Linnean Society of London, Biological Journal of the Linnean Society, 2009, 98, 61,76. [source] The Whitaker test: 35 years onBJU INTERNATIONAL, Issue 1 2010Eric W. Lupton Study Type , Diagnosis (case series) Level of Evidence 4 OBJECTIVE To describe a 25-year experience of using the Whitaker test in a single tertiary centre for assessing upper urinary tract dilatation, and to evaluate the role of perfusion pressure-flow studies in contemporary urological surgery for equivocal upper tract obstruction. PATIENTS AND METHODS In all, 143 patients with suspected upper urinary tract obstruction were investigated by at least one Whitaker test. The original method was extended to include observations on high flow-rate perfusion, abnormal renal pelvic peristalsis and loin pain with no pressure increase. Data on clinical presentation, perfusion pressure-flow studies, diuresis renography and choice of initial therapy were collected prospectively, and the long-term clinical outcome was analysed retrospectively. RESULTS In total, 145 studies were assessed; the Whitaker test showed obstructive features at conventional or higher flow rates in 61 cases and unobstructive patterns in 53. There were four equivocal results. Seventeen studies showed abnormal peristalsis within the renal pelvis and in 10 there was ,sensory' loin pain during the test. In patients with idiopathic hydronephrosis, there was agreement between the results of the pressure-flow studies and diuresis renography in 72%. The Whitaker test determined or contributed to the clinical management in 84% of the cases studied. It was accurate in its prediction of outcome in 77% of cases where obstruction was diagnosed and in 77% of unobstructive cases. CONCLUSIONS The Whitaker test continues to have a role in modern urological surgery. It should be reserved for assessing potential upper urinary tract obstruction in the following circumstances: equivocal results from less invasive tests; suspected obstruction with poor kidney function; loin pain with a negative diuresis renogram; suspected intermittent obstruction; and gross dilatation with a positive diuresis renogram. [source] The choice of timing for diuresis renography:the F+0 methodBJU INTERNATIONAL, Issue 1 2001A.A.B. Adeyoju Objective To investigate a method of diuresis renography where the radiopharmaceutical and frusemide (diuretic) are given simultaneously, in contrast to conventional renography which involves an intravenous injection with frusemide 20 min after administering the radiopharmaceutical (F+20) or 15 min before (F,15), with particular interest in the effect of this change on assessing split renal function and interpreting upper tract drainage dynamics. Patients and methods In a prospective study, 29 patients (18 women and 11 men, mean age 47 years, range 21,86) were assessed. Each patient had two renograms taken over a 48-h period, either by the F+20 or F,15, and the F+0 method. Data for split renal function and drainage curves were obtained in the usual way. Two independent assessments of the drainage curves were obtained and the results compared. Results The split function assessments were identical (<5% variation) in all but two patients; 26 of 29 (90%) gave identical conclusions about the drainage curves. The three patients with discrepancies between the studies had either hugely dilated upper tracts or otherwise had multiple complicating factors, e.g. impaired renal function, neuropathic bladder. Conclusions F+0 renography has been used in paediatric urological practice before, but there are no comparative studies and no data on its use in adults. This prospective study confirmed that in investigating dilated upper tracts, the F+0 technique gives similar results to the conventional techniques. The F+0 method has the potential to reduce the time required to undertake standard F+20 renography but it may not be useful in evaluating the grossly dilated upper tract, where the F,15 technique has the best record in terms of reducing equivocal results. [source] | |||||||||||||