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51.
目的 探讨Y染色体无精症因子C区(azoospermia factor C,AZFe)无精症缺失基因(deleted-in-azoospermia,DAZ)家族基因拷贝缺失与中国男性原发不育之间的关系。方法 运用多重PCR与PCR-RFLP检测技术,对210例已生育男性、216例原发无精症与189例严重少精症患者Y染色体AzFc区域DAZ基因家族的基因拷贝数进行分析。结果 在所有已生育男性中未检出DAZ基因拷贝的完全或部分缺失,而在原发无精症与严重少精症患者中DAZ基因拷贝完全缺失率分别为8.8%和12.2%,DAZ1/DAZ2共缺失率分别为8.3%和5.3%。结论 在中国男性原发无精症与严重少精症患者中存在较高频率的DAZ基因拷贝缺失现象,提示Y染色体AZFc区域DAZ基因家族基因拷贝的完全与部分缺失是中国男性原发不育的遗传高风险因子。 相似文献
52.
Dong-Hai Xiong Hui Shen Peng Xiao Yan-Fang Guo Ji-Rong Long Lan-Juan Zhao Yao-Zhong Liu Hong-Yi Deng Jin-Long Li Robert R Recker Hong-Wen Deng 《Journal of bone and mineral research》2006,21(3):424-437
A genome-wide screen was conducted using a large white sample to identify QTLs for FNCS geometry. We found significant linkage of FNCS parameters to 20q12 and Xq25, plus significant epistatic interactions and sex-specific QTLs influencing FNCS geometry variation. INTRODUCTION: Bone geometry, a highly heritable trait, is a critical component of bone strength that significantly determines osteoporotic fracture risk. Specifically, femoral neck cross-sectional (FNCS) geometry is significantly associated with hip fracture risk as well as genetic factors. However, genetic research in this respect is still in its infancy. MATERIALS AND METHODS: To identify the underlying genomic regions influencing FNCS variables, we performed a remarkably large-scale whole genome linkage scan involving 3998 individuals from 434 pedigrees for four FNCS geometry parameters, namely buckling ratio (BR), cross-sectional area (CSA), cortical thickness (CT), and section modulus (Z). The major statistical approach adopted is the variance component method implemented in SOLAR. RESULTS: Significant linkage evidence (threshold LOD = 3.72 after correction for tests of multiple phenotypes) was found in the regions of 20q12 and Xq25 for CT (LOD = 4.28 and 3.90, respectively). We also identified eight suggestive linkage signals (threshold LOD = 2.31 after correction for multiple tests) for the respective geometry traits. The above findings were supported by principal component linkage analysis. Of them, 20q12 was of particular interest because it was linked to multiple FNCS geometry traits and significantly interacted with five other genomic loci to influence CSA variation. The effects of 20q12 on FNCS geometry were present in both male and female subgroups. Subgroup analysis also revealed the presence of sex-specific quantitative trait loci (QTLs) for FNCS traits in the regions such as 2p14, 3q26, 7q21 and 15q21. CONCLUSIONS: Our findings laid a foundation for further replication and fine-mapping studies as well as for positional and functional candidate gene studies, aiming at eventually finding the causal genetic variants and hidden mechanisms concerning FNCS geometry variation and the associated hip fractures. 相似文献
53.
Yan Wang Xuesong Zhang Songhua Xiao Ning Lu Zheng Wang Mi Zhou 《Journal of orthopaedic surgery and research》2006,1(1):13-7
Objectives
To investigate clinical effects and manual operational point of Bryan cervical disc prosthesis in Chinese, to observe the stability and range of movement (ROM) post-operatively. 相似文献54.
55.
报告5例女性骨盆骨折合并阴道损伤,占骨盆骨折41例中的12.2%,均为交通事故伤,都合并有失血性休克,开放伤3例,闭合伤2例,治疗作阴道修补术2例,用碘仿纱条填塞阴道2例。未作处理1例,均治愈,阴道损伤表现为四型;横行撕裂伤,纵行撕裂伤,斜行撕裂伤和刺伤,强调早期诊断,及时治疗以防止合并症。 相似文献
56.
在健康杂种犬10只中,分别以15、30、45μg/kg 尼莫地平静注行控制性降压,监测平均动脉压和其它血流动力学指标。结果表明,15μg/kg、30μg/kg 和 45μg/kg 静注后,平均动脉压1min 时分别下降19.44%、29.93%和33.60%,45min 恢复对照水平。降压期间除心输出量指数、每搏量指数和总外周阻力指数外,其它各项指标无显著性改变。因此,我们认为尼莫地平可试用于临床控制性降压,其效果有待临床进一步观察。 相似文献
57.
58.
OBJECTIVE: To investigate the hemodynamic effects of a moderately low-salt diet in a 9-week, randomized, double-blind, crossover study in 20 hypertensive, ambulatory patients. METHODS: All subjects followed a 9-week, low-salt diet. During this period, they received capsules containing either lactose or salt in 4-week treatment periods, separated by a 1-week washout period. Hemodynamic and biological parameters were evaluated on the day of randomization and at the end of weeks 4 and 9. We defined a low-sodium diet (LSD) as a salt-restriction period with lactose capsules, and a normal-sodium diet (NSD) as a salt-restriction period with capsular salt supplementation. RESULTS: Blood pressure was significantly lower during LSD compared with NSD. This fall in blood pressure was associated with a decrease in peripheral resistance in carotid and forearm circulation. Brachial artery diameter was larger during LSD whereas carotid artery diameter remained unchanged. The changes in brachial artery were: (1) not related to blood pressure changes; (2) positively related to age, and (3) negatively correlated with baseline intracellular sodium content. CONCLUSIONS: These results suggest that moderate low-salt restriction is capable of decreasing blood pressure and peripheral resistance in carotid and forearm circulation. The increase in brachial, but not carotid, artery diameter following salt restriction suggests a difference in salt dependence among different arteries. 相似文献
59.
本文对300个寰椎的后桥和侧桥的存在情况作了观察。其中129个寰椎(43.0%)有后部分桥,22个寰椎(7.3%)有后完整桥;34个寰椎有侧部分桥(11.3%),16个寰椎(5.3%)有侧完整桥。经统计学检验,在左右侧后完整桥及左右侧侧完整桥间均无显著性差异。对寰椎横突孔、后弧孔及侧弧孔内径的测量显示,绝大部分后弧孔(92.0%)较同侧横突孔小,且右横突孔与右后弧孔间存在高度显著性差异(P<0.01)。此外,还测量了两种完整骨桥的宽度,探讨了狭小后弧孔对正常椎动脉机能的可能影响,分析了文献中关于寰椎桥的起源。 相似文献
60.
Wistar rats were divided into 8 groups:control, 300 ppm F, 130 ppm F, 300 ppm Al, 1200 ppm Al, 130 ppm Al + 130 ppm F. 300 ppm Al + 300 ppm F and 1200 ppm Al + 300 ppm F. The chemicals were mixed into the standard diet. The animals were fed on the diets for 12 weeks. Contents of F, Al, Ca and P in the blood (or serum) and humerus were determined at the end of 12 weeks. The results showed that the level of F in the blood and bone in the unadulterated F group was increased, especially F in the bone reached a level more than 10 times that of the control. In the 3 mixture groups, blood F and bone F were lowered, while blood F was restored to normal level, but bone F was not nevertheless, the results showed that Al was in antagonism to the absorption of F. In the unadulterated Al groups, blood and bone Al did not parallel with the amount of Al administered. The level of Al in the median Al group was higher than that of the high Al group. Taking the level of blood and bone Al as a measure, when different doses of Al were administered with F, in the low and median dosage of Al, F was in antagonism to Al absorption, but in case of high dosage of Al, F was in potentiation to Al absorption. In all the experimental groups serum P was elevated, but serum Ca was not disturbed. Bone Ca and P were decreased only in the 3 groups with unadulterated F as well as unadulterated and adulterated high dosage of Al. Mechanism of the nonlinearity of Al absorption vs Al dosage, as well as the dual effect of F on the absorption of Al was proposed. 相似文献