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21.
22.
为探讨醇脱氢酶(ADH)基因和醛脱氢酶(ALDH)基因多态性与酒依赖患病的相互关系,用耳血干血痕聚合酶链反应、等位基因特异性寡核苷酸探针方法,检测乙醇代谢酶ADH和ALDH基因型在我国蒙、汉民族酒依赖与非酒依赖者中分布频率。结果显示在酒依赖组(汉族52例,蒙族31例)与正常对照组(汉族48例,蒙族35例)之间:汉族的ALDH2基因型频率与等位基因频率的分布差异有非常显著性(P<0.01),而蒙族则表示为ADH2基因型频率与等位基因频率的分布差异有非常显著性(P<0.01)。这提示汉族酒依赖的发病与ALDH2基因有关,蒙族则与ADH2基因有关。  相似文献   
23.
病人生理监测仪是临床医学的主要仪器,由于涉及技术流程的功能定位不同,功能需求也就不同,其功能配置也就有所不同。从生理监测仪相关应用领域的分解技术功能定位出发,讨论装备管理的功能配置问题。  相似文献   
24.
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   
25.
Recognition of the many benign and malignant tumors that occur in the skull base is now simple, given three-dimensional CT scanning and MRI with enhancement. Recent developments in surgical technique have allowed these tumors to be approached, but only in the past two to three years has radical surgery been possible.  相似文献   
26.
A double-contrast upper gastrointestinal examination on a woman who had undergone endoscopic heater probe therapy one day earlier for multiple arteriovenous malformations revealed shallow, irregular, and linear ulcers at the sites of heater probe coagulation. Multiple shallow ulcers may therefore develop as a direct complication of heater probe therapy. Radiologists should be aware of this complication to avoid diagnostic confusion in these patients.  相似文献   
27.
High-specificity in-situ hybridization. Methods and application.   总被引:2,自引:0,他引:2  
We describe a technique of in-situ hybridization using oligonucleotide probes employing the expression of immunoglobulin VH genes as a model. Optimal conditions for hybridization with the 35S-labeled oligonucleotide probes were established with monoclonal B-cell lines that express VH genes of known nucleic acid sequence. The range of sensitivity and specificity achieved with this technique is documented. Under conditions of high stringency, this method can detect the expression of highly related VH hypervariable regions.  相似文献   
28.
The haemodynamics of the uterine arteries and myometrium were assessed using Doppler ultrasound in forty consecutive patients requiring treatment for invasive mole and choriocarcinoma. The investigations were performed prior to the commencement of chemotherapy and the subjects followed prospectively. The Doppler waveforms from the uterine arteries were analysed using the pulsatility index. It was found that patients with a pulsatility index of 1.1 or less were significantly more likely to develop drug resistance than those with a higher value (P < 0.04). There was no significant association between the pulsatility index and metastatic disease or uterine bleeding. Five out of eight patients who developed drug resistance could have avoided initial inadequate treatment if the Doppler findings were included in the scoring system for selecting chemotherapy for these tumours. It can be concluded that assessment of the uterine arteries using the pulsatility index prior to the treatment of patients with invasive mole and choriocarcinoma is of help in predicting those who will develop drug resistance.  相似文献   
29.
本文从理论上提出了红细胞沉降速度的准确概念,阐明了红细胞沉降过程所包含的物理和生理信息,提出了一种新型测量红细胞沉降速度及其它特征参数的方法,并给出了其主体、硬件和软件设计要点。  相似文献   
30.
Diabetes in NOD mice is an autoimmune disease which is characterized by the infiltration of islets of Langerhans by large numbers of T cells. Some of these infiltrating T cells are clearly islet-cells-specific; however, many or most of these T cells could be attracted nonspecificity into these lesions. To study NOD pancreas-infiltrating T cells, we fused these cells with BW5147 to make T cell hybridomas. Ninety-four pancreas-derived T hybrids were analyzed of which 12 responded specifically to islet cells by secreting IL-2. Only CD3+, CD4+ hybrids responded to islet cells in our assay, and a large proportion of these hybrids were islet-cell reactive. T cell receptor (TCR) V beta element usage was heterogeneous in islet-reactive hybridomas.  相似文献   
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