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71.
The variations in the body length, swimming legs and some setaeof the freshwater cyclopid Acanthocyclops robustus were analysedduring an annual cycle in the field, and in laboratory experimentsat different culture temperatures. In Lake Créteil. ashallow temperate sand-pit lake, there is a seasonal morphologicalvariation of the setae: the plumose forms were restricted tothe warmer season and the spinose ones to colder periods. Contraryto other years, the specific spine formula ofthe swimming legs (3-4-4-4) did not vary during the referenceyear. In laboratory experiments, both sex and post-embryonicdevelopmental temperatures had an effect on the length of adults.A significant parental effect on body length was detected. Pairswith anomalous spine formulae produced offspring either withanomalous spine formulae or typical 3-4-4-4 formulae. No significanteffects of parental culture temperatures, offspring culturetemperatures and sex on the total number of spines were found.Modification of plumose into spinose setae did not occur, whateverthe offspring developmental temperatures. The results presentedhere suggest that the alterations of the appendages of the cyclopidA.robustus could be compared to the cyclomorphosis in otherzooplanktonic groups, and contribute to our understanding ofthe role of phenotypic induction in aquatic biology. 相似文献
72.
M. Hergersberg Jaya Balakrishnan Thomas Bettecken Francoise Chevalier-Porst Christian Brägger René Burger Inge Einschenk Sabina Liechti-Gallati Michael Morris Daniel Schorderet Francine Thonney Hans Moser Naseem Malik 《Human genetics》1997,100(2):220-223
We have analysed 1173 cystic fibrosis (CF) chromosomes from Switzerland for eight mutations in the CF transmembrane conductance
regulator (CFTR) gene. This permitted the identification of 88.5% of all mutations present. A novel insertion mutation in
exon 20 of the CFTR gene, 3905insT, was discovered. This mutation accounted for 4.8% of CFTR gene mutations in Switzerland
and has since been identified in other populations of probable Swiss descent. It is associated with a highly variable clinical
phenotype but always with pancreatic insufficiency. Haplotype analysis with three intragenic microsatellites in the CFTR gene
showed that the mutation is associated with a haplotype rarely identified on other CFTR alleles and, therefore, that the frequency
of the mutation in Switzerland is explained by a founder effect of a relatively recent mutation event.
Received: 17 February 1997 / Accepted: 26 March 1977 相似文献
73.
Nissim Garti Francoise Tibika Sara Sarig Shaul Perlberg 《Biochemical and biophysical research communications》1980,97(3):1154-1162
A new method has been established to follow the inhibitory effect of some polymeric-dicarboxylic-amino-acids and other poly-anionic derivatives. The technique is based on using calcium specific electrode to measure continuously free calcium ion activity in solution to assess the formation of calcium oxalate precipitate.The retardation effect of Poly-L-glutamic and aspartic acids has been established in 5–100 ppm range and compared to other monomeric and polymeric compounds with inactivated functional groups. The retardation effect is in agreement with previous reports on inhibition effect on crystal growth rate of seed crystals, with the same retardants.The inhibitory effect was also determined with normal urine and compared to pathological urine. 相似文献
74.
Joseph P. Guiraud Francoise Vezinhet Pierre Galzy Jacques Albert 《Archives of microbiology》1972,82(2):101-110
Résumé Le milieu de croissance préalable semble intervenir sur l'aptitude des levures à métaboliser l'éthanol et l'acide acétique. Dans certains cas, les deux substrats activent l'oxydation des réserves. Ce phénomène se produit avec des levures cultivées sur milieu synthétique contenant du glucose 2% ou de l'éthanol 1%. Il ne se produit pas avec des levures cultivées sur ce même milieu synthétique contenant du glucose 0,5%. Il ne peut cependant être expliqué, ni par une richesse supérieure des cellules en réserves glucidiques, ni par un déséquilibre alimentaire, ni par une différence d'activité respiratoire.
Influence of culture conditions on ethanol and acetic acid metabolism of yeast
Summary The medium in which yeasts are grown seems to modify their ability to metabolize ethanol and acetic acid. In certain cases, the two substrates activate the oxidation of reserves. The phenomenon is observed with yeasts grown on synthetic medium with glucose 2% or ethanol 1%. It is never observed with yeasts grown on the same medium with glucose 0.5%. It cannot be explained either by an elevated cellular level of carbohydrate reserves, by a nutritional imbalance, or by a difference in respiratory activity.相似文献
75.
76.
Melissa C. Brouwers Michelle E. Kho George P. Browman Jako S. Burgers Francoise Cluzeau Gene Feder Béatrice Fervers Ian D. Graham Steven E. Hanna Julie Makarski 《CMAJ》2010,182(10):1045-1052
Background
We undertook research to improve the AGREE instrument, a tool used to evaluate guidelines. We tested a new seven-point scale, evaluated the usefulness of the original items in the instrument, investigated evidence to support shorter, tailored versions of the tool, and identified areas for improvement.Method
We report on one component of a larger study that used a mixed design with four factors (user type, clinical topic, guideline and condition). For the analysis reported in this article, we asked participants to read a guideline and use the AGREE items to evaluate it based on a seven-point scale, to complete three outcome measures related to adoption of the guideline, and to provide feedback on the instrument’s usefulness and how to improve it.Results
Guideline developers gave lower-quality ratings than did clinicians or policy-makers. Five of six domains were significant predictors of participants’ outcome measures (p < 0.05). All domains and items were rated as useful by stakeholders (mean scores > 4.0) with no significant differences by user type (p > 0.05). Internal consistency ranged between 0.64 and 0.89. Inter-rater reliability was satisfactory. We received feedback on how to improve the instrument.Interpretation
Quality ratings of the AGREE domains were significant predictors of outcome measures associated with guideline adoption: guideline endorsements, overall intentions to use guidelines, and overall quality of guidelines. All AGREE items were assessed as useful in determining whether a participant would use a guideline. No clusters of items were found more useful by some users than others. The measurement properties of the seven-point scale were promising. These data contributed to the refinements and release of the AGREE II.Evidence-based guidelines are systematically developed statements aimed at assisting clinicians and patients in decisions about appropriate health care for specific clinical circumstances. 1 Guidelines assist decision-makers in solving system-level and population-level challenges. 2,3 The potential benefits of guidelines, however, are only as good as the quality of the guidelines themselves. Rigorous development and strategies for reporting are important precursors to successful implementation of the resulting recommendations. 4The quality of guidelines is variable, often falling short of basic standards.5–7 To address this variability, an international team of guideline developers and researchers, the AGREE Collaboration (Appraisal of Guidelines, Research and Evaluation), created a generic instrument to assess the process of guideline development and reporting. The result of this work was the AGREE instrument, a 23-item tool targeting six quality-related domains.8,9 It became accepted by many as the standard for guideline evaluation.10As with any new assessment tool, ongoing development of the instrument is required. The AGREE Next Steps Consortium was established to conduct a program of research aimed at improving the AGREE and advancing the overall guideline enterprise. We report on the first of two studies designed to achieve these goals. This study focused on four key issues related to methodology and implementation (Figure 1).Open in a separate windowFigure 1Program of research.First, the original four-point response scale was not in keeping with standards for test construction that are intended to maximize the reliability and discriminability of an instrument and minimize the number of appraisers required to evaluate a guideline.11 To address this issue, we introduced a seven-point response scale, tested its performance and conducted a preliminary analysis of some of its measurement properties.Second, to be of value, the AGREE instrument needs to be easy to apply and needs to generate information that is useful. To generate a reliable estimate of guideline quality, it is recommended that the 23 items of the AGREE instrument be applied by four independent reviewers.8,9 This process can be cumbersome and resource-intensive. However, no systematic analysis has been undertaken previously to determine if all items of the AGREE instrument generate information that is equally useful across different groups. This fact opens the possibility that fewer than 23 items, and varying combinations of items unique to different users, may be sufficient for evaluation purposes. Therefore, we explored whether evidence exists to inform the development of abridged versions of the AGREE that could be tailored to the unique priorities of different user groups.Third, to be useful as well, the AGREE ratings should be associated with outcomes that are relevant to guideline usage. In keeping with previous findings,4 guidelines of higher quality should be more attractive, endorsed or used than those of lower quality. We therefore explored whether these relationships existed and whether they were consistent across different types of users.Finally, given that the AGREE had been in the field for some time, we systematically collected feedback from users on how the items and domains might be improved, updated and refined.In combination with the results of the second study,12 the data were used by the consortium to craft the AGREE II,13 the next version of the AGREE instrument. 相似文献77.
Creswell C Hentges F Parkinson M Sheffield P Willetts L Cooper P 《Mental health in family medicine》2010,7(1):49-57
Anxiety disorders in childhood are common, disabling and run a chronic course. Cognitive behaviour therapy (CBT) is effective but expensive and trained therapists are scarce. Guided self-help treatments may be a means of widening access to treatment. This study aimed to examine the feasibility of guided CBT self-help in primary care for childhood anxiety disorders, specifically in terms of therapist adherence, patient and therapist satisfaction and clinical gain.Participants were children aged between five and 12 years referred to two primary child and adolescent mental health services (PCAMHSs) in Oxfordshire, UK, who met diagnostic criteria for a primary anxiety disorder. Of the 52 eligible children, 41 anxious children were assessed for anxiety severity and interference before and after receiving CBT self-help delivered via a parent (total therapy time = five hours) by primary mental health workers (PMHWs). Therapy sessions were rated for treatment adherence and parents and PMHWs completed satisfaction questionnaires after treatment completion. Over 80% of therapy sessions were rated at a high level of treatment adherence. Parents and PMHWs reported high satisfaction with the treatment. Sixty-one percent of the children assessed no longer met the criteria for their primary anxiety disorder diagnosis following treatment, and 76% were rated as 'much'/'very much' improved on the Clinical Global Impression-Improvement (CGI-I) scale. There were significant reductions on parent and child report measures of anxiety symptoms, interference and depression. Preliminary exploration indicated that parental anxiety was associated with child treatment outcome. The findings suggest that guided CBT self-help represents a promising treatment for childhood anxiety in primary care. 相似文献
78.
Christine Michel Francoise Vincent Christine Duval Marie-Christine Poelman Monique Adolphe 《Free radical research》1992,17(4):279-289
The aim of this work was to study the proliferation pathological perturbations of cultured chondrocytes in response to menadione, an oxygen free radicals producing drug. Rabbit articular chondrocytes in monolayer culture were treated with 10-5, 1.5.M-5 and 2.10-5M of menadione during three days. A dose dependent decrease of the proliferative capacity was observed. Flow cytometry analysis revealed a perturbation of the cell cycle progression consisting in an accumulation of cells in the S and G2 + M phases. This growth perturbation was due to oxygen radicals production since a treatment with catalase suppressed these toxic effects. Furthermore, to identify oxygen derived radicals in the cellular suspension of cultures treated with menadione, we used a technique of spin-trapping coupled with electron spin resonance (ESR). The ESR signal corresponding to the DMPO hydroxyl radical adduct (DMPO-OH) has been detected. The spectra observation indicated the actual production of hydroxyl radical. However, superoxide anions have not been identified; this fact can be explained by the low reactivity of these anions with DMPO and by the decomposition of signal DMPO-OOH to DMPO-OH. 相似文献
79.
Baylis F 《Developing world bioethics》2003,3(2):142-150
This commentary responds to genetic testing of African ancestry through a series of personal narratives that reveal a complex, intimate, and individualised process of identity formation. The author discusses both how her family and others outside her family have fostered and challenged her sense of black identity. She concludes by maintaining that racial identity is not in the genes but in the world in which we live and the stories we construct and are able to maintain. 相似文献
80.
Schanstra JP Duchene J Praddaude F Bruneval P Tack I Chevalier J Girolami JP Bascands JL 《American journal of physiology. Heart and circulatory physiology》2003,284(6):H1904-H1908
Bradykinin B(2) receptor knockout mice (B(2)-/-) have been useful to study the role of bradykinin under pathological conditions. With the use of these mice, it was shown that bradykinin plays an important role in angiogenesis, heart failure, salt-induced hypertension, and kidney fibrosis. Data on the role of the bradykinin B(2) receptor under physiological conditions using these mice are controversial and scarce, because these mice have no typical phenotype. For this reason, we have studied, under physiological conditions, renal hemodynamics as well as a number of morphometric glomerular parameters of B(2)-/- mice on a homogenized genetic background and on mice bred in a pathogen-free environment. Backcrossed B(2)-/- mice had normal blood pressure and normal apparent renal hemodynamics and morphology. However, reduced renal nitrite excretion and glomerular cGMP content were found, which was associated with a reduced glomerular capillary surface area. These differences had, however, no detectable effects on renal hemodynamics. These differences between B(2)-/- and wild-type mice might become important under pathological conditions as shown by a number of studies using these bradykinin B(2) receptor knockout mice. 相似文献