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21.
Linkage analysis under the two-locus model and the admixture model was compared on pedigree data for a common disease stimulated under a model of genetic heterogeneity. The ascertainment of families was designed so that the samples had a large proportion of families segregating for both disease loci. The two-locus linkage analysis model did not demonstrate increased power of detecting linkage or more accurate estimates of the recombination fraction, theta than did the admixture model linkage analysis. When a sample was purposely chosen so that all of the families were segregating for both loci, then the two-locus lod score analysis was better. However, the increased power depended on assuming the correct gene frequency for the linked locus. It can be concluded that under the conditions of genetic heterogeneity examined here, testing for linkage under the admixture model is the preferred method of analysis. However, this is not a general conclusion that can apply to all two-locus disease models.  相似文献   
22.
The use of medical records in research can yield information that is difficult to obtain by other means. When such records are released to investigators in identifiable form, however, substantial privacy and confidentiality risks may be created. These risks become more common and more serious as medical records move to an electronic format. In 1996, the state of Minnesota enacted legislation with respect to consent requirements for the use of medical records in research. This legislation has been widely criticized because--it is claimed--it creates an unnecessary impediment to research. In this article, we show that these arguments rest upon misinterpretation and/or misrepresentation of the 1996 legislation. A consent requirement had actually been present in Minnesota since 1976 (though codified in a patient rights statute rather than a privacy statute). The 1996 law does not require specific consent, as often claimed, but rather only a general authorization. The campaign against the Minnesota legislation appears to have been motivated by concern with respect to the then impending federal privacy rule. The HIPAA rule, as enacted, is in fact less stringent with respect to consent than the Minnesota consent law. On the other hand, the Minnesota consent law has not been effectively applied or enforced. As we change the way we manage sensitive medical information, new efforts are needed to provide protection against the confidentiality risks in research. Patient consent is an important tool in this regard. New instrumentalities are needed to solicit and document consent.  相似文献   
23.
One hundred and ten patients with common bile duct (CBD) stones were treated in the Department of Surgical Gastroenterology at SGPGIMS, Lucknow, India between January 1989 and December 1992. The primary modality of treatment was surgery in 62 patients (group I) and endoscopic sphincterotomy (ES) in 48 (group II). The two groups were well matched with respect to clinical features and presence of medical risk factors. Surgical clearance of CBD stones was achieved in 58 patients (93.5%; group Ia). Four patients (7%) had retained stones following surgery (group Ib). In group II, the CBD was cleared by endoscopic means in 20 out of 48 patients (42%) and was categorized into group IIa. In the remaining patients ES was followed by CBD exploration (group IIb). Significantly higher morbidity was seen in patients needing CBD surgery following attempted endoscopic clearance, because of ES-related complications, such as bleeding, cholangitis, septicaemia and numerous others. Use of ES to treat CBD stones on a routine basis was therefore not found to be any better than one-time surgical exploration.  相似文献   
24.
腹腔镜下胆总管探查取石32例临床分析   总被引:3,自引:0,他引:3  
目的 探讨腹腔镜下胆总管探查取石术的可行性、适应症.方法 回顾性分析2003年2月~2005年12月32例腹腔镜下胆总管探查取石术的临床资料.结果 32例均在胆道镜的配合下完成,其中胆总管切开取石后置T管引流27例,胆总管切开取石后Ⅰ期缝合5例.2例发生术后胆漏.结论 对腹腔镜下胆总管探查取石术,不管是采用T管引流还是Ⅰ期缝合,只要掌握手术方式及适应症,腹腔镜下治疗胆总管结石是可行的.  相似文献   
25.
目的探讨腹腔镜和胆道镜治疗胆囊胆总管结石的临床效果。方法2003年7月-2005年8月我院有18例胆囊并胆总管结石手术先行腹腔镜胆囊切除,然后切开胆总管用胆道镜探查,取出胆总管结石。结果1例腹腔镜胆囊切除术中转开腹,17例均顺利完成腹腔镜胆囊切除、胆道镜胆总管探查术。结论腹腔镜和胆道镜治疗胆囊胆总管结石的临床效果可靠。  相似文献   
26.
We report here the complete nucleotide sequence and predicted polyprotein sequence of HeLa cell-adapted human rhinovirus 16 (HRV16). This virus is more suitable than human rhinovirus 14 (HRV14) for clinical studies, and its growth and physical properties are favorable for biochemical and crystallographic analysis. The complete message-sense RNA genome of HRV16 is composed of 7124 bases, not including the poly(A) tail. An open reading frame, extending from base 626 to 7084 predicts a polyprotein containing 2152 amino acid residues. Comparison with other rhinovirus sequences shows HRV16 is much more representative of human rhinoviruses than HRV14. No apparent relationship was found between receptor group and amino acid sequence in VP1, the capsid protein bearing the binding site for the intercullular adhesion molecule-1 (ICAM-1) in both HRV14 and HRV16.Genbank accession number: L24917.  相似文献   
27.
Effects of oestradiol (E2) have been studied on the in vitro T cell-dependent differentiation of B cells from peripheral blood and spleen using normal donors and patients with the antibody deficiency disease CVID. We also studied whether it modifies T cell DNA synthesis. The effect of E2 was examined on cultures of B cells with T cells for IL-2-driven immunoglobulin secretion or of T cells for phytohaemagglutinin (PHA)-driven DNA synthesis. Interestingly, in control experiments without E2, the normal sex difference in immunoglobulin production is reversed in CVID. The data show that for normal individuals there is no major difference between male and female donors in the in vitro actions of E2 on blood B and T lymphocytes. With normal blood B cells, E2 failed to affect IgM production, but it did inhibit IgG. In normal splenic cells, E2 increased both IgM and IgG secretion in a similar way to the tonsillar cell data previously reported. E2 on normal blood T cell DNA synthesis was stimulatory. With blood cells from CVID patients an interesting contrast was seen. As with normal B cells, E2 had no effect on IgM secretion by those CVID blood B cells able to secrete IgM. However, a difference between patients and normals was that E2 did not inhibit the IL-2-driven IgG production by those CVID B cells able to secrete IgG. For T cell function, the stimulatory effect of E2 on CVID T cell DNA was as in normal T cells. However, E2 failed to restore CVID B and T cell function to normal levels. These data suggest that there may be subtle defects in the pathway of action of E2 in CVID lymphocytes.  相似文献   
28.
广东2003年末SARS患者冠状病毒抗原抗体动态特征分析   总被引:1,自引:0,他引:1  
目的分析SARS-IgG、SARS-IgM、核壳蛋白-IgG抗体和核壳蛋白抗原的变化特点并探讨其意义。方法采用酶联免疫方法对2003年末至2004年初新发4例SARS病人的系列血清进行上述4项的滴度检测。结果在病人较早期的血清中可以检测到核壳蛋白抗原,随着抗体水平的升高,抗原含量迅速下降。抗体E升下降快,在最高水平维持时间短,并且除第1例外,其余3例的抗体滴度均小于1:100,核壳蛋白抗体变化规律与总的IgG抗体一致,但滴度更低。结论抗体变化规律与前次流行不同,抗体水平变化快,应注意及时采集标本。抗原检测可作为一种实验室诊断依据。核壳蛋白抗体可考虑用于早期诊断。  相似文献   
29.
胆总管的矢状断层解剖研究   总被引:1,自引:0,他引:1  
刘树伟  王凡 《解剖学杂志》1993,16(5):391-394
在30套成人腹部连续矢状断层标本上,胆总管与下腔静脉主要出现于R2-R3断层;胆总管胰腺段与胰头的关系有部分包埋,完全包埋及胰腺后型;十二指肠大乳头集中出现于R3断层;胆总管的行程有4种形式。文内还探讨了矢状断层里胆总管各段的毗邻及识别标志。  相似文献   
30.
The mechanisms of virus-induced airway hyperresponsiveness in asthma and allergy and the failure of host defence in patients suffering from secondary airway infections are still largely unknown. The aim of this study was to examine whether the presence of allergic rhinitis or susceptibility to recurrent sinusitis affects the structural and cellular changes in nasal mucosa during natural colds and convalescence. We compared the mucosal changes in biopsy samples during acute natural colds (days 2-4 of illness) and convalescence (3 weeks later) in patients with allergic rhinitis (n = 9), patients with susceptibility to sinusitis (n = 19) and healthy controls (n = 20). We saw similarly increased numbers of mucosal T and B lymphocytes and mast cells and increased vascular density during the acute colds compared to convalescence in all the three groups. The allergic subjects had elevated levels of eosinophils in the acute phase (P = 0.03), and the allergic and sinusitis-prone subjects had elevated levels of epithelial T cells (P = 0.04) and low levels of mast cells (P = 0.005) in convalescence compared to the control group. The sinusitis-prone subjects lacked intraepithelial cytotoxic cells in convalescence. In the allergic subjects, the reticular basement membrane was thicker in the acute phase compared to the convalescence (P = 0.05). These results suggest that various cells of the airways, including inflammatory and structural cells, are involved during viral respiratory infections in subjects with allergic rhinitis. The small numbers of mast cells and cytotoxic lymphocytes in the sinusitis-prone subjects may be related to their susceptibility to bacterial complications.  相似文献   
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