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41.
42.
C. Masri G. Chagnon D. Favier H. Sartelet E. Girard 《Biomechanics and modeling in mechanobiology》2018,17(4):939-950
This work aims at observing the mechanical behavior of the membranous and spongy portions of urethrae sampled on male cadavers in compliance with French regulations on postmortem testing, in accordance with the Scientific Council of body donation center of Grenoble. In this perspective, a thermostatic water tank was designed to conduct ex vivo planar tension tests in a physiological environment, i.e., in a saline solution at a temperature of \(37 \pm 1\) \({^{\circ }}\hbox {C}\). In order to observe the anisotropy of the tissues, the samples were tested in two directions. Tests consisting of a series of load–unload cycles of increasing amplitudes were performed to highlight their viscous behavior. The results were then discussed according to the microstructure of tissue, which was investigated using different staining methods and histological analysis. The observed behaviors were then fitted using an anisotropic hyperelastic or a visco-hyperelastic matrix–fiber model. 相似文献
43.
Benjamin Buemann Marie-Claude Vohl Monique Chagnon Yvon C. Chagnon Jacques Gagnon Louis Prusse France Dionne Jean-Pierre Desprs Angelo Tremblay Andr Nadeau Claude Bouchard 《Obesity (Silver Spring, Md.)》1997,5(3):186-192
Several investigations have suggested that body fat distribution is influenced by nonpathologic variations in the responsiveness to Cortisol. Genetic variations in the glucocorticoid receptor (GRL) could therefore potentially have an impact on the level of abdominal fat. A restriction fragment length polymorphism (RFLP) has previously been detected with the BelI restriction enzyme in the GRL gene identifying two alleles with fragment lengths of 4.5 and 2.3 kb. This study investigates whether abdominal fat areas measured by computerized tomography (CT) are associated with this polymorphism in 152 middle-aged men and women. The less frequent 4.5-kb allele was found to be associated with a higher abdominal visceral fat (A VF) area independently of total body fat mass (4.5/4.5 vs. 2.3/2.3 kb genotype; men: 190.7 ± 30.1 vs. 150.7 ± 33.3 cm2, p=0.04; women: 132.7 ± 37.3 vs. 101.3 ± 34.5 cm2, p=0.06). However, the association with AVF was seen only in subjects of the lower tertile of the percent body fat level. In these subjects, the polymorphism was found to account for 41% (p=0.003) and 35% (p=0.007), in men and women, respectively, of the total variance in AVF area. The consistent association between the GRL polymorphism detected with BelI and AVF area suggests that this gene or a locus in linkage disequilibrium with the BelI restriction site may contribute to the accumulation of AVF. 相似文献
44.
Current phylogenetic tree reconstruction methods assume that there is a
single underlying tree topology for all sites along the sequence. The
presence of mosaic sequences due to recombination violates this assumption
and will cause phylogenetic methods to give misleading results due to the
imposition of a single tree topology on all sites. The detection of mosaic
sequences caused by recombination is therefore an important first step in
phylogenetic analysis. A graphical method for the detection of
recombination, based on the least squares method of phylogenetic
estimation, is presented here. This method locates putative recombination
breakpoints by moving a window along the sequence. The performance of the
method is assessed by simulation and by its application to a real data set.
相似文献
45.
We used the repetitive character of transposable elements to isolate a
non-LTR retrotransposon in Drosophila subobscura. bilbo, as we have called
it, has homology to TRIM and LOA elements. Sequence analysis showed a 5'
untranslated region (UTR), an open reading frame (ORF) with no RNA-binding
domains, a downstream ORF that had structural homology to that of the I
factor, and, finally, a 3' UTR which ended in several 5-nt repeats. The
results of our phylogenetic and structural analyses shed light on the
evolution of Drosophila non-LTR retrotransposons and support the hypothesis
that an ancestor of these elements was structurally complex.
相似文献
46.
Mélanie J Chagnon Noriko Uetani Michel L Tremblay 《Biochimie et biologie cellulaire》2004,82(6):664-675
The protein tyrosine phosphatases (PTPs) have emerged as critical players in diverse cellular functions. The focus of this review is the leukocyte common antigen-related (LAR) subfamily of receptor PTPs (RPTPs). This subfamily is composed of three vertebrate homologs, LAR, RPTP-sigma, and RPTP-delta, as well as few invertebrates orthologs such as Dlar. LAR-RPTPs have a predominant function in nervous system development that is conserved throughout evolution. Proteolytic cleavage of LAR-RPTP proproteins results in the noncovalent association of an extracellular domain resembling cell adhesion molecules and intracellular tandem PTPs domains, which is likely regulated via dimerization. Their receptor-like structures allow them to sense the extracellular environment and transduce signals intracellularly via their cytosolic PTP domains. Although many interacting partners of the LAR-RPTPs have been identified and suggest a role for the LAR-RPTPs in actin remodeling, very little is known about the mechanisms of action of RPTPs. LAR-RPTPs recently raised a lot of interest when they were shown to regulate neurite growth and nerve regeneration in transgenic animal models. In addition, LAR-RPTPs have also been implicated in metabolic regulation and cancer. This RPTP subfamily is likely to become important as drug targets in these various human pathologies, but further understanding of their complex signal transduction cascades will be required. 相似文献
47.
Variation of physico-chemical parameters along a river transect through the Okavango Delta,Botswana 总被引:1,自引:0,他引:1
The Okavango Delta depends on water quantity and quality to sustain its ecosystem services. Whereas many studies have been carried out on its hydrology, few have been done on water quality in the delta. Water pH, electrical conductivity (EC), dissolved oxygen (DO), turbidity, total suspended solids (TSS) and dissolved organic carbon (DOC) were monitored at 10 sites along the Okavango–Boro–Thamalakane–Lake Ngami system almost fortnightly from June 2008 to June 2010. Water quality in the delta was generally good, despite high evapotranspiration rates which would normally produce very saline waters. Electrical conductivity and water temperature increased with distance from Mohembo to Lake Ngami, the former most likely due to evapoconcentration. In contrast, pH, DO, turbidity and TSS decreased with distance from Mohembo to Boro at the lower end of the seasonal floodplain, before increasing again to Lake Ngami. Dissolved oxygen and TSS most likely declined due to biological uptake and particle sedimentation, respectively. Strong and significant relationships were observed between TSS and turbidity and between DOC and EC, indicating that turbidity and EC could be useful proxies for routine estimations of TSS and DOC, respectively, in the delta. 相似文献
48.
The suitability of using macroinvertebrates as bioindicators of stream water quality was tested in the Mkondoa River in an agricultural area at Kilosa, using the rapid bioassessment protocol. The family biotic index (FBI) showed marked variation in water quality along the stream from values ranging from 4.1 to 5.0 in the upstream reaches, indicating good water quality, 5.3 to 5.5 in the mid-reaches and 6.0 to 6.5 in the lower reaches. The water quality index (WQI) indicated that water quality was fair (77 ± 0.98) in the upstream reach of the Mkondoa, marginal (55 ± 0.86) in the midstream reach and poor (33 ± 0.45) in the downstream reach. There were significant relationships between biological oxygen demand and dissolved oxygen and the occurrence of specific taxa, mainly Chironomus and Caenis. Significant changes in macroinvertebrate abundance were mostly related to changes in water quality. As in other parts of the world, macroinvertebrate communities proved to be good biological indicators of water quality and they should be used as bioindicators in long-term monitoring of this river. 相似文献
49.
Clonidine, 0.05 mg twice daily, was evaluated in a multicentre, randomized, placebo-controlled, double-blind crossover study in 66 patients who had had menopausal flushing for less than 1 year. Although the placebo effect was substantial, clonidine reduced the frequency of attacks significantly more than did placebo. In three of the four trials the patients'' comparisons of symptoms before and after crossover indicated significantly greater improvement when the crossover was from placebo to clonidine rather than the reverse. The frequency, severity and duration of attacks were reduced by clonidine in 78%, 89% and 88% of the patients respectively, and by placebo in 50%, 53% and 50%. Side effects were minimal and their pattern was the same for clonidine as for placebo. Clonidine''s action as a peripheral vascular stabilizer makes it potentially useful for the treatment of menopausal flushing. It would be prudent to include clonidine at the beginning of treatment so that its efficacy could be assessed in each individual. Its use would enhance the effects of the usual management of the menopausal syndrome, which consists of explanation, reassurance and, sometimes, the use of tranquillizers. Clonidine is a symptomatic medication that makes flushing more tolerable and should reduce the number of patients who would otherwise be exposed to the risks of estrogens. 相似文献
50.