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21.
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   
22.
本文采用改良的邻革之酚自氧化法,对51例无遗传性疾病早孕妇女绒毛细胞进行了SOD活力测定。其比活力为426.2±48.4u/mg蛋白(x±SD),测定值范围为217.2~589.1u/mg蛋白,P95>915.0u/mg蛋白。  相似文献   
23.
24.
We have produced and characterized a monoclonal antibody, MH1, which selectively labels rod horizontal cells and Müller cells in the goldfish retina. Biochemical and tissue distribution studies indicate that MH1 may recognize four out of five classes of intermediate filament proteins in goldfish: vimentin, desmin, glial fibrillary acidic protein (GFAP), and keratin, but not neurofilament. The intermediate filament which is labeled strongest in the retina is vimentin. In the goldfish retina, the only type of horizontal cells recognized by MH1 appear to be rod horizontal cells. This result suggests that the rod horizontal cell, an interneuron, and Müller (glial) cells share a common antigen: vimentin, which is usually only expressed in mesenchymal origin cells. The development of rod horizontal cells in the goldfish retina was also studied using MH1. The cells were not labeled by MH1 until 4-6 weeks posthatching, a stage in which the animals are already visually active. MH1 also did not label any horizontal cell in the region close to the ora terminalis in the goldfish retina. These results suggest that either the emergence and maturation of rod horizontal cells occur late during goldfish retinal development or the expression of vimentin itself occurs late in the development of rod horizontal cells.  相似文献   
25.
本文综述本校传染病学教研室1955~1995年间所取得的科研成果。内容包括10余种传染病与寄生虫病的临床和基础研究,其中以华支睾吸虫病、恙虫病等有广东特色的传染病以及伤寒、痢疾、病毒性肝炎等影响人民健康最普遍的传染病为重点。反映了建国以来各个时期本教研室对防治这些传染病所作的贡献。所取得的成果,相当一部分通过多年来的验证,已获得广大传染病工作者所认同或列为常规,部分已获得部委级奖励。现在重温这些成果,可能起承前启后的意义。  相似文献   
26.
In treating Meniere's disease, author has found that the compatible use of heavy dosage of Gu Sui Bu (骨碎补 Rhizoma Drynariae) can produce very good effect for relieving dizziness, vertigo and tinnitus. Some of the sample cases are cited in the following.  相似文献   
27.
1 病例资料 患者 胡某,男,50岁,渔民,江西省余干县瑞洪镇胡宋村人。常年在鄱阳湖捕鱼,每年服用吡喹酮至少1次,已连续服用七八年,未曾出现不良反应。2006年10月,无明显诱因出现发热,体温38℃左右,无腹痛、畏寒等,经当地医院B超检查发现胆囊息肉,抗炎治疗5d,体温未退。查间接血凝试验(IHA)、酶联免疫吸附试验(ELISA)均阳性,  相似文献   
28.
Larsen syndrome consists of skeletal dysplasia with multiple joint dislocations and a characteristic facies. The basis of this abnormality is a generalized mesenchymal disorder involving connective tissues. We describe our findings in a woman who was referred at 28 weeks' gestation due to multiple fetal anomalies suspected initially at an 18-week ultrasound examination. On three-dimensional (3D) ultrasound we found the fetus had bilateral genu recurvatum. Further 3D examination at 36 weeks confirmed the lower limb anomaly and revealed facial anomalies that led to the diagnosis of Larsen syndrome. An elective Cesarean section was performed at 38 weeks' gestation to minimize neurological sequelae. Magnetic resonance imaging was performed postnatally and showed pachygyria, colpocephaly and agenesis of the corpus callosum. In this case, 3D ultrasound facilitated the prenatal diagnosis of Larsen syndrome. A careful prenatal investigation for other associated anomalies such as those of the cardiovascular or neurological systems is warranted with this diagnosis. These associated lesions are likely to have a greater impact on prognosis than the classic symptoms of Larsen syndrome and a collaborative approach is necessary to optimize delivery and postnatal management of an affected fetus.  相似文献   
29.
BACKGROUND: Immunotherapy with anti-IgE antibodies for treatment of allergy is promising but a short half-life and extremely high cost limit its application. OBJECTIVE: We sought to develop IgE vaccines that induce longer-lasting auto-antibodies to neutralize self-IgE as an alternative therapy. METHODS: The vaccine was made by conjugating three synthetic peptides corresponding to human IgE receptor-binding sites to a carrier, hepatitis B surface antigen. To test the immunogenicity of the vaccine, rats were immunized with the vaccine or hepatitis B surface antigen as control. Serum IgG titres to human IgE and the IgE of other species were measured. The inhibition by rat antisera of the binding of human IgE to its receptor was assessed by ELISA, flow cytometry analysis, and passive cutaneous anaphylaxis (PCA), and its ability to recognize receptor-bound IgE was examined. The in vivo effect of the vaccine was evaluated in trichosanthin-sensitized mice and rats. In the preventative study, vaccination started before sensitization commenced, while in the treatment study, vaccination started after sensitization. Sensitized mice and rats receiving injections of the carrier served as controls. Trichosanthin-specific IgE was measured using PCA. RESULTS: Sera from vaccine-immunized rats contained high titre antibodies that reacted with soluble and plate-bound but not with receptor-bound human IgE; they also reacted with mouse, rat, and dog IgE. Furthermore, the sera inhibited the binding of human IgE to its receptor in a dose-dependent manner. In preventative and treatment studies, serum trichosanthin-specific IgE levels were significantly reduced in vaccinated groups compared with controls. CONCLUSION: Antibodies against self-IgE can be induced by IgE peptide-based vaccines, which are effective in preventing the increase of IgE and in down-regulating IgE in sensitized animals.  相似文献   
30.
膳食纤维分析方法的简化   总被引:14,自引:0,他引:14  
郑建仙  耿立萍 《营养学报》1997,19(2):207-211
对SelvendranRR等人的冷中性洗涤剂纤维提取分析法(CNDF)进行简化,改变了各溶剂的处理时间,省去了湿球研磨与超声波处理步骤。将原法中SLS-PAW-DWSO处理时间15h,30min和16h分别延长为22h,40min与22h,化学分析与透射电镜观察结果表明,简化法对膳食纤维的提取分析效果与原推荐法相同,更加方便与实用。  相似文献   
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