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排序方式: 共有9401条查询结果,搜索用时 12 毫秒
91.
Purpose: The AZFc region spans about 3.5 Mb and contains many amplicons causing recombination events. Several papers have reported
the occurrence of AZFc partial deletions resulting from non allelic homologous recombination (NAHR) (“gr-gr”, “b1-b3” or “b2-b3”
deletions), particularly in infertile patients. DAZ genes are present in 4 copies and rearrangements involve a modification of the number of DAZ genes.
Methods: In addition to STS plus/minus PCR, we developed a quantitative technique using real time PCR (Q-PCR) to determine the number
of DAZ genes. Fourteen DNA controls were selected to validate the use of Q-PCR to detect AZFc microrearrangements, and sperm DNA
samples from 30 fertile men were studied.
Results: Rearrangements of 14 controls were well identified with Q-PCR, and 2 AZFc partial deletions were detected in fertile men
(1 “gr-gr” and 1 “b2-b3”).
Conclusion: Q-PCR represents a well-adapted method to detect microrearrangements of the Y-chromosome, complementary to STS analysis. 相似文献
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93.
Zengfeng Zhao Jianzhuang Xiao Denis Damidot Sbastien Rmond David Bulteel Luc Courard 《Materials》2022,15(9)
Adherent hardened cement paste attached to recycled concrete aggregates (RCA) generally presents a higher porosity than natural aggregates, which induces a lower porosity in the properties of RCA. The characterization of the adherent hardened cement paste content (HCPC) in the fine RCA would promote better applications of RCA in concrete, but the determination of HCPC in fine RCA is not well established. A simple method based on salicylic acid dissolution was specifically developed to quantify the HCPC in RCA, especially for RCA containing limestone aggregates. The results demonstrated that the soluble fraction in salicylic acid (SFSA) was equal to the HCPC for white cement and slightly lower for grey Portland cement, which was also confirmed by a theoretical approach using modelling the hydration of cement paste with the chemical equations and the stoichiometric ratios. The physical and mechanical properties of RCA (e.g., water absorption) were strongly correlated to the SFSA. For industrial RCA, SFSA did not give the exact value of HCPC, but it was sufficient to correlate HCPC with the other properties of RCA. The water absorption could be estimated with good accuracy for very fine RCA (laboratory-manufactured RCA or industrial RCA) by extrapolating the relationship between water absorption and HCPC, which is very important for concrete formulation. 相似文献
94.
Guillaume Lefebvre Armelle Renaud Nathalie Rocourt Bernard Cortet Luc Ceugnart Anne Cotten 《Joint, bone, spine : revue du rhumatisme》2013,80(5):534-537
Primary vertebral osteosarcoma is a rare type of osteosarcoma, differing from the appendicular forms by an incidence peak occurring at a higher age and a poorer prognosis, due to the difficulties of the surgical treatment. We present five cases of histologically proven primary vertebral osteosarcomas followed in our institution between 2004 and 2012. They allow to illustrate some essential radiologic features, useful to evoke this rare entity. 相似文献
95.
Vincenzo Malafarina Francisco Uriz-Otano Raquel Iniesta Lucía Gil-Guerrero 《Journal of the American Medical Directors Association》2013,14(1):10-17
BackgroundMuch interest has been focused on nutritional treatment of sarcopenia, loss of muscle mass and performance associated to aging; however, its benefits are unclear.ObjectiveTo analyze the relevance of nutritional treatment of sarcopenia and assess the effects of supplementation on muscle mass and function within the aged population.MethodsWe searched Medline and the Cochrane Library for controlled trials published between 1991 and 2012. We have assessed the quality, type of intervention, the cohort used, the way muscle mass was measured, and the outcomes of the various studies.ResultsWe have included 17 studies, with a total of 1287 patients, aged between 65 and 85 on average. An improvement in muscle mass was proven, whether measured with bioelectrical impedance analysis or dual energy x-ray absorptiometry, and an improvement in strength was also proven.ConclusionNutritional supplementation is effective in the treatment of sarcopenia in old age, and its positive effects increase when associated with physical exercise. The main limitation of this treatment is lack of long-term adherence. A healthy diet associated with a physically active lifestyle and possibly with aerobic exercise are the basis of healthy aging, which is the aim of all doctors treating aged people must seek. 相似文献
96.
Thibaud Pintiaux David Viet Virginie Vandenbossche Luc Rigal Antoine Rouilly 《Materials》2013,6(6):2240-2261
Commercial α-cellulose was compression-molded to produce 1A dog-bone specimens under various operating conditions without any additive. The resulting agromaterials exhibited a smooth, plastic-like surface, and constituted a suitable target as replacement for plastic materials. Tensile and three-points bending tests were conducted according to ISO standards related to the evaluation of plastic materials. The specimens had strengths comparable to classical petroleum-based thermoplastics. They also exhibited high moduli, which is characteristic of brittle materials. A higher temperature and higher pressure rate produced specimens with higher mechanical properties while low moisture content produced weaker specimens. Generally, the strong specimen had higher specific gravity and lower moisture content. However, some parameters did not follow the general trend e.g., thinner specimen showed much higher Young’s Modulus, although their specific gravity and moisture content remained similar to control, revealing a marked skin-effect which was confirmed by SEM observations. 相似文献
97.
98.
Luc Noreau Johanne Desrosiers Line Robichaud Patrick Fougeyrollas Annie Rochette 《Disability and rehabilitation》2013,35(6):346-352
Purpose: Much more attention should be paid to instruments documenting social participation as this area is increasingly considered a pivotal outcome of a successful rehabilitation. The purpose of this study was to document the reliability of a participation measure, the Assessment of Life Habits (LIFE-H), in older adults with functional limitations.Methods: Eighty-four individuals with physical disabilities living in three different environments were assessed twice with the LIFE-H, an instrument that documents the quality of social participation by assessing a person's performance in daily activities and social roles (life habits).Results: The intraclass correlation coefficients (ICC) computed for intrarater reliability exceeded 0.75 for seven out of the 10 life habits categories. For interrater reliability, the total score and daily activities subscore are highly reliable (ICC ??0.89), and the social roles subscore is moderately reliable (ICC?=?0.64). ‘Personal care’ is the category with the highest ICC, and for five other categories ICCs are moderate to high (<?0.60).Conclusion: LIFE-H is a valuable addition to instruments that mostly emphasize the concepts of function or functional independence. It is particularly meaningful to evaluate the participation of older adults in significant social role domains such as recreation and community life. It may be considered among the instruments having the best fit with the ICF definition of participation (the person's involvement in a life situation) and a majority of its related domains. 相似文献
99.
100.