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31.
11β-羟类固醇脱氢酶与2型糖尿病   总被引:12,自引:0,他引:12  
11β-羟类固醇脱氢酶(11β-HSDs)催化氢化可的松(皮质酮)和可的松(脱氢皮质酮)的相互转化,对调节局部糖皮质激素的活性起着重要作用,而糖皮质激素可诱导胰岛素抵抗。肝、脂肪等组织内11β-HSD活性的改变与肥胖、2型糖尿病等疾病密切相关。  相似文献   
32.
目的评价烤瓷贴面的修复效果。方法选择20例患者制作烤瓷贴面92个。复诊时对烤瓷贴面的边缘适合性,边缘着色及颜色进行评价;同时采用牙龈出血指数和菌斑指数评价治疗前后的牙周状况。观察时间为12~18个月。结果5颗牙烤瓷贴面失败,成功率为95.7%;烤瓷贴面治疗前后牙龈出血指数无显著性差异(P>0.05),治疗后菌斑指数降低(P<0.01)。结论烤瓷贴面具有较好的治疗效果。  相似文献   
33.
Summary In this study the technique of labelling the cell membrane with DPH fluorescence polarization was used to observe the membrane fluidity of B lymphocytic cell lines and tonsillar cells from healthy persons; the modulation effect on membrane-fluidity induced by McAbs against isotypic and idiotypic determinants of IgM from patients with leukemia was studied as well. The expression of the corresponding isotypic and idiotypic determinants of IgM on the cell membrane was determined. The results show that the membrane fluidity of leukemic cell lines is remarkably higher than that of tonsillar cells from healthy persons, and McAbs against isotypic determinants of leukemic IgM can enhance the membrane fluidity of all kinds of cells mentioned above. However, the anti-idiotypic monoclonal antibody increased only the membrane fluidity of leukemic cell lines. These results indicated that there was a close relationship between the effect of McAbs on cell membrane fluidity and the expression of corresponding isotypic and idiotypic determinants of IgM on the cell membrane.  相似文献   
34.
A new hemoglobin variant with a Ser----Phe substitution at position beta 49(CD8) was discovered in two members of a family living in the Canary Islands, Spain. Detection was by polyacrylamide gel electrophoresis and by reversed phase high performance liquid chromatography. The variant, which constituted 43% and 45%, respectively, in the two heterozygotes, was slightly unstable. Its presence did not affect hematological values though there was a mild reticulocytosis.  相似文献   
35.
15例离退休健康男性老人和9例红细胞增多症男性病人返回平原后,记忆功能改变的特点:①两组受试者除5例成绩下降外,苏州记忆成绩高于西宁成绩(p<0.01)。②记忆成绩降低现象存在于20%左右的人中。③高原缺氧和返平原脱适应均主要影响短时记忆。  相似文献   
36.
The physico-chemical methods for the study of the binding of ligands to tubulin are examined in-depth, emphasizing the assumptions on which they are based and their limitations. The criteria of specificity and linkage to protein self-association are presented. It is shown that, of the direct equilibrium binding techniques, Hummel-Dreyer gel permeation chromatography and rapid ultracentrifugation are applicable only when binding is not linked to protein self-association. Disc filtration is valid only when the reverse unbinding reaction is very low. Binding linked to protein self-association can be measured by batch gel permeation or by dialysis equilibrium. The indirect techniques, such as fluorescence perturbation or difference absorption spectroscopy are discussed in terms of the assumptions on which they are based. They are shown to be used best only after characterization of the binding by direct techniques. Equilibrium binding parameters can also be deduced from careful kinetic experiments. Comparison of calorimetrically measured enthalpies of binding to van't Hoff enthalpies derived from equilibrium measurements indicates that the method of choice is calorimetric, while comparison with van't Hoff analysis can reveal the existence of reaction steps not detected by equilibrium measurements. Use of other indirect approaches, such as titration of an enzymic activity, can also lead to the detection of additional steps. The criteria are set up for the proper data analysis of ligand binding linked to protein self-association and the selection of the proper mode of linkage. It is shown how the thermodynamic contributions of various moieties of a ligand can be established by a rational structural modification of the ligand and the proper analysis of the binding measurements, in which all non-specific entropic contributions are taken into account. It is demonstrated also how a similar analysis of binding data can lead to conclusions about the reaction pathway from a comparison of equilibrium thermodynamic measurements on judiciously modified ligand molecules.  相似文献   
37.
R Hu  C Beck  Y B Chang  L J DeGroot 《Autoimmunity》1992,12(2):103-106
Inheritance of Graves' disease has been linked to the HA-DR3 gene product which may function in some specific way in antigen presentation. To determine whether the first extracellular domain of this protein, which is specifically involved in antigen presentation, has the same sequence in patients with Graves' disease and in normal individuals, we have amplified the second exon using the polymerase chain reaction, and then cloned and sequenced the DNA segment. In eight subjects with Graves' disease, sequences identical to prototypic reported sequence for DRB1*0301 were recovered, and in two individuals sequences varied by a few nucleotides, leading to 1-3 amino acid substitutions which did not occur in a pattern. Sequences identical to the prototypic sequence known as DRB3*0101, also previously known as DRw52, were also recovered. Thus the HLA-DRB1 and B3 genes present in patients with autoimmune disease appear to be the same as those present in the general population. These observations indicate that a unique allele is not present in patients with autoimmune disease, but rather that the normal DR3 allele itself, in a manner yet to be described, increases the probability of developing autoimmune thyroid disease.  相似文献   
38.
39.
本文报告了经手术病理证实的53例甲状腺肿瘤,均作了甲状腺造影和B超检查.通过比较分析,我们认为造影对确定肿瘤的良、恶性以及延伸到胸骨后的异位甲状腺肿瘤有其优越性,是一项有效的检查方法;超声则能准确地判断肿瘤的囊、实性,适合碘过敏患者的检查.两种检查各有特点,配合使用有利于对甲状腺肿瘤的诊断和治疗.  相似文献   
40.
柠檬月亮     
明月的公司叫MOONRIVER,不知道的人总以为那些带着粗糙划痕的石壁圈住的是一个咖啡厅,其实不是。屋子里只有素色的窗帘和柔软的沙发,茶几上没有咖啡,但永远放着新鲜的柠檬水,明月接待客 从不做笔录,优质的采访机放在不被注意的地方,工作的时候,电源信号灯轻轻闪烁,明明灭灭。  相似文献   
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