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31.
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
32.
A comprehensive anatomic and radiographic analysis of the peribursal fat plane in 12 cadavers confirmed that the fat plane seen on radiographs represents extrasynovial fat lining the subacromial bursa and documented the anatomic relations of the bursa. A three-part retrospective clinical evaluation of rotator cuff tears, calcific tendinitis, and rheumatoid arthritis was performed. Two osteoradiologists blindly graded the appearance of the peribursal fat plane with the shoulder in external versus internal rotation in 21 patients with arthrographically intact rotator cuffs and 21 patients with disrupted rotator cuffs. The peribursal fat plane was seen better with disrupted rotator cuffs. The peribursal fat plane was seen better with the shoulder in internal rotation and was seen in 60% of control subjects but only 21% of patients with rotator cuff tears. Partial or complete obliteration of this fat plane is a sensitive (79%) but less specific (60%) indicator of rotator cuff tears. Obliteration of the peribursal fat plane by inflammatory processes in adjacent tissues, including calcific tendinitis and rheumatoid arthritis, occurred with a high frequency. 相似文献
33.
CA von Arnim R Spoelgen ID Peltan M Deng S Courchesne M Koker T Matsui H Kowa SF Lichtenthaler MC Irizarry BT Hyman 《The Journal of neuroscience》2006,26(39):9913-9922
The beta-amyloid (Abeta) precursor protein (APP) is cleaved sequentially by beta-site of APP-cleaving enzyme (BACE) and gamma-secretase to release the Abeta peptides that accumulate in plaques in Alzheimer's disease (AD). GGA1, a member of the Golgi-localized gamma-ear-containing ARF-binding (GGA) protein family, interacts with BACE and influences its subcellular distribution. We now report that overexpression of GGA1 in cells increased the APP C-terminal fragment resulting from beta-cleavage but surprisingly reduced Abeta. GGA1 confined APP to the Golgi, in which fluorescence resonance energy transfer analyses suggest that the proteins come into close proximity. GGA1 blunted only APP but not notch intracellular domain release. These results suggest that GGA1 prevented APP beta-cleavage products from becoming substrates for gamma-secretase. Direct binding of GGA1 to BACE was not required for these effects, but the integrity of the GAT (GGA1 and TOM) domain of GGA1 was. GGA1 may act as a specific spatial switch influencing APP trafficking and processing, so that APP-GGA1 interactions may have pathophysiological relevance in AD. 相似文献
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35.
血清前列腺特异性抗原增高的病理基础 总被引:17,自引:0,他引:17
对血请前列腺特异性抗原(PSA)高于4μg/L,且有病理检查资料的67例前列腺疾病患者,进行了分析。其中前列腺癌24例,非癌前列腺病变43例。结果显示前列腺癌组血清PSA明显高于非癌组(P<0.01)。以血清PSA10μg/L为低限值,诊断癌的灵敏性为83.3%。特异性为74.4%,认为血请PSA4~10μg/L应视为癌的危险范围。上皮血屏障的破坏和上皮细胞增生是血清PSA升高的基础 相似文献
36.
人胎盘提取组织凝血活酶及其质量评价 总被引:2,自引:2,他引:0
利用人胎盘抽提得组织凝血活酶,并对其质量进行了评价,同时初步应用于临床。结果显示:用含表面活性剂的抽提剂粉碎抽提的效果较好,所得组织凝血活酶重复性、灵敏度、稳定性均令人满意;与上海荣盛生物制品厂生产的PT试剂盒比较相关性好:Y=2.75+0.905x,r=0.9253,经相关系数t检验,t=26.5469,P<0.001,呈直线正相关。临床初步应用显示:肝病及抗凝治疗等病人PT时间明显延长,93例正常人x=11.3秒,s=0.96秒,正常范围9.42-13.18秒。 相似文献
37.
References: 《生殖医学杂志》2007,16(Z1):79-83
Objectives:To assess the clinical outcomes of frozen-thawed blastocysts transfer in natural and hormonally controlled cycles.Methods:A retrospective analysis of natural and hormonally controlled cycle for 246 frozen-thawed blastocyst transfer cycles,the clinical pregnancy rate,implantation rate,early abortion rate were compared.Results:Of the 192 hormonally controlled cycles,the cancel rate,clinical pregnancy rate per ET,implantation rate and abortion rate were 7.3%(14/192),53.9%(96/178),38.8%(131/338)and 11.5%(11/96)respectively,whereas in 54 natural cycles,these rates were 16.7%(9/54),68.9%(31/45),52.9%(45/85)and 16.1%(5/31)respectively.There was no significant difference between the two groups with regard to the clinical pregnancy and abortion rate per ET,but the cancel rate and implantation rate were higher in natural cycles.However,the pregnancy and implantation rates of patients without PCOS in hormonal control cycles(57.2%,40.9%)were similar with those in natural cycles(P>0.05).Conclusion:These findings suggested that both hormonally controlled and natural cycles had similar pregnancy outcomes in frozen-thawed blastocysts transfer. 相似文献
38.
介绍营养补充品中刺激剂的毛细管气相色谱和气相色谱质谱联用检测方法.试样采用碱提,液-液分配提取,以HP-5毛细管柱为分离柱,用氮磷检测器测定.实验结果表明:该方法操作简便,分析速度快,结果可靠.添加平均回收率为75.4%~143.1%,相对标准偏差为0.27%~5.5%,检出限为5~40μg/L. 相似文献
39.