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51.
Toxicity of cyclosporine (CsA), an immunosuppressive drug widely used in transplantation, to the transplanted kidney creates a serious side effect. Therefore, searching for sensitive indicators of nephrotoxic action is well worth the effort. In this work we decribe the results of estimation of urine concentration of lysosomal enzymes widely present in the kidney: N-acetyl--D-glucosaminidase (NAG), its isoenzyme NAG-B and -glucuronidase (-Gr). The studies were conducted in various periods after transplantation of kidneys, on patients under various treatments and receiving different doses of CsA. The results indicate a substantial dependence of the activity of NAG and NAG-B on CsA doses and the period after transplantation. The enzyme proved to be also a sensitive indicator of graft rejection. No such dependence was observed in the case of -Gr.  相似文献   
52.
We describe the separation of alanylaminopeptidase (AAP) from urine into two isoenzymes: a particulate and a soluble form. The separation was accomplished using ion-exchange column chromatography on DEAE-52 cellulose. The purity of the isolated forms was confirmed electrophoretically. We attempted to create a method allowing the quantitative assessment of AAP isoenzymes in urine based on electrophoretic separation in 7.5% polyacrylamide gel with subsequent densitometric analysis. The content of AAP isoenzymes in examined urine was estimated using ultracentrifugation. The differences in the content of cytosolic and microsomal forms were observed suggesting the possibilities of using AAP isoenzymes in diagnostics. Furthermore, the effect of temperature on the activity of AAP separated on DEAE-52 cellulose was studied.  相似文献   
53.
Previously, we reported the direct design of highly potent nonpeptide 3-oxo-1,4-benzodiazepine fibrinogen receptor antagonists from a constrained, RGD-containing cyclic semipeptide. The critical features incorporated into the design of these nonpeptides were the exocyclic amide at the 8-position which overlaid the Arg carbonyl, the phenyl ring which maintained an extended Gly conformation, and the diazepine ring which mimicked the gamma-turn at Asp. In this paper, we investigate conformational preferences of the 8-substituted benzodiazepine analogues by examining structural modifications to both the exocyclic amide and the seven-membered diazepine ring and by studying the conformation of the benzodiazepine ring using molecular modeling, X-ray crystallography, and NMR. We found that the directionality of the amide at the 8-position had little effect on activity and the (E)-olefin analogue retained significant potency, indicating that the trans orientation of the amide, and not the carbonyl or NH groups, made the largest contribution to the observed activity. For the diazepine ring, with the exception of the closely analogous 3-oxo-2-benzazepine ring system described previously, all of the modifications led to a significant reduction in activity compared to the potent 3-oxo-1, 4-benzodiazepine parent ring system, implicating this particular type of ring system as a desirable structural feature for high potency. Energy minimizations of a number of the modified analogues revealed that none could adopt the same low-energy conformation as the one shared by the active (S)-isomer of the 3-oxo-1, 4-benzodiazepines and 3-oxo-2-benzazepines. The overall data suggest that the features contributing to the observed high potency in this series are the orientation of the 3-4 amide and the conformational constraint imposed by the seven-membered ring, both of which position the key acidic and basic groups in the proper spatial relationship.  相似文献   
54.
研究生作为PBL指导教师在药理学教改中的探索   总被引:1,自引:0,他引:1  
药理系首次进行聘用研究生作为PBL指导教师的教改尝试,深刻体会到其重要性所在。研究生具有知识面宽、概念清楚、基础知识扎实等诸多优势,有利于提高本科生的教学质量。药理系组织研究生参加教学培训、开展讨论、吸纳有益的建议;提高研究生对PBL教学的重视程度、消除研究生顾虑;争取研究生导师的大力支持;并由教授亲自检查并督促研究生教学工作。作为PBL教学指导教师,研究生是学生与任课教授、讲师之间的中介人和桥梁,有利于提高学生的综合素质、教师教学水平。  相似文献   
55.
目的:探讨应用口服耐受的方法抑制抗透明带抗体的产生,为卵巢早衰的治疗提供一种新途径。方法:将100只小鼠随机分为对照组、模型组、小剂量治疗组、中剂量治疗组和大剂量治疗组。各治疗组小鼠给予透明带多肽灌胃,剂量分别为每次1μg、10μg和100μg,共7次。灌胃4次后,经皮下注射免疫原建立小鼠自身免疫性卵巢早衰模型。免疫荧光法检测小鼠外周血和卵巢中抗透明带抗体的表达。结果:中剂量和大剂量治疗组小鼠外周血中抗透明带抗体的阳性率分别为15%和45%,明显低于模型组的80%,具有统计学意义(P<0.01)。中剂量治疗组小鼠卵巢中抗透明带抗体的阳性率为20%,明显低于模型组的70%,具有统计学意义(P<0.01)。结论:适当剂量的透明带多肽能够很好地诱导口服耐受、抑制机体抗透明带抗体的产生。  相似文献   
56.
Primary immune thrombocytopenia (ITP) of childhood is an autoimmune disease characterized by abnormally increased destruction of platelets and decreased megakaryopoiesis. Stromal‐derived factor‐1 (SDF‐1) plays a role in megakaryopoiesis and may be involved in the pathogenesis of ITP. Five single nucleotide polymorphisms (SNPs) of the SDF‐1 gene, including rs1801157, rs2839693, rs2297630, rs1065297, and rs266085, were assessed in 100 children with ITP and 126 healthy controls. The genotypes were analyzed by tetra ARMS polymerase chain reaction and confirmed by direct sequencing. Compared with controls, the rs2839693 A/A and rs266085 C/T genotypes were decreased in ITP patients (P = 0.004 and 0.007, respectively). The odds ratios of the latter genotypes were 0.48, 95% CI 0.28–0.82. Further analysis of the relationship between SDF‐1 polymorphisms and clinical features showed that rs2297630 A/G was associated with protection from chronicity (P = 0.002; OR, 0.07; 95% CI, 0.01–0.61) and steroid dependence (P = 0.007; OR, 0.10; 95% CI, 0.01–0.84) in ITP patients. However, rs266085 genotype C/C was associated with risk of steroid dependence (P = 0.012, OR 3.87, 95% CI 1.27–11.77). The findings of this study suggest that SDF‐1 gene variations may be associated with the occurrence and prognosis of childhood ITP.  相似文献   
57.
目的 基于Aβ损伤的PC12模型,观察人参皂苷Rb1对线粒体自噬的调节作用。方法 用Aβ损伤PC12细胞建立体外AD模型,采用人参皂苷Rb1进行干预后,利用透射电镜观察自噬情况,Western blot检测LC3Ⅱ/Ⅰ、p62、PINK1、parkin、NDP52和OPTN蛋白的表达,荧光实时定量PCR检测LC3p62PINK1parkinNDP52OPTN mRNA水平。结果 人参皂苷Rb1高剂量促进细胞中自噬小体包裹受损线粒体,升高LC3Ⅱ/Ⅰ比值(P < 0.05),减少p62蛋白水平(P < 0.05);同时,人参皂苷Rb1显著增加了PINK1蛋白表达(P < 0.01),同时减少OPTN及NDP52蛋白水平(P < 0.05);此外,人参皂苷Rb1高剂量组parkinOPTN mRNA表达显著上调(P < 0.01),低剂量组PINK1NDP52 mRNA表达也显著上调(P < 0.05)。结论 人参皂苷Rb1神经保护作用与调节线粒体自噬相关,通过激活PINK1/parkin通路促进线粒体自噬而改善体外AD模型损伤情况。  相似文献   
58.
59.
Background: Central venous access systems are frequently used for delivery of medications; however, few studies have compared surgical and postoperative complications of right versus left access via the subclavian vein (SCV). The aim of this study was to compare the surgical and postoperative complications associated with Port-A-Cath system insertion via the right and left SCV. Methods: The medical records of patients who received Port-A-Cath insertion via the SCV for parenteral chemotherapy between August 2004 and July 2008 were reviewed. The incidence of surgical and postoperative complications was compared between patients who received right- versus left-SCV Port-A-Cath insertion. Results: A total of 1,848 patients were included in the study. Right-SCV catheterization was attempted in 1,029 (55.7%) patients and was successful in 866 (84.2%). Left-SCV catheterization was attempted in 819 (44.3%) patients and was successful in 651 (79.5%). The mean length of postoperative follow-up was 417.3 ± 401.3 and 396.7 ± 379.9 days for the right- and left-SCV groups, respectively. The incidence of SCV puncture failure was significantly lower in the right-SCV group (12.3%) compared with the left-SCV group (16.8%, p = 0.006). The incidence of catheter knotting at the ipsilateral brachiocephalic vein was also significantly lower in the right-SCV group (0.0%) compared with the left-SCV group (0.5%, p = 0.038), as was the incidence of catheter occlusion (1.0% for right SCV vs. 3.5% for left SCV, p = 0.001). Conclusion: These findings suggest that the right-SCV approach is superior to the left-SCV approach for Port-A-Cath insertion.  相似文献   
60.
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