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41.
Five stable hybridoma lines were prepared using the myeloma cell line P3-X63-Ag.653 and spleen cells of mice hyperimmunized by pig transferrin. All hybridomas grew well in mouse peritoneal cavity and produced antibodies of the IgG1 subclass. Antibody preparations obtained from ascitic fluids tested for their capacity of antigen precipitation. No precipitation was obtained with single antibodies and with pairs of antibodies. Three out of 10 possible triads gave clear and sharp precipitation zones and rings in immunodiffusion tests performed in agar gel. All 5 antibodies were shown by quantitative enzyme-immunoassay to be specific for pig transferrin: no cross-reaction was obtained with mouse, human, horse and sheep transferrins.  相似文献   
42.
The purpose of this study was to determine whether 20 patients who received an early postmastectomy rehabilitation treatment program showed more improvement in range of shoulder motion and functional activities than 13 patients who received instruction for exercise only. Data were obtained at preoperatively, three days after operation, at discharge and at postdischarge one month for each patient on parameters such as range of motion of the ipsilateral shoulder joint, upper extremity circumferential measurements, as well as 10 elements of shoulder function. Postoperatively, both groups showed an increased range of motion of the shoulder joint and improved functional activities, but the group that received postoperative rehabilitation management had a better range of shoulder motion and less difficulty in five items for functional assessment. This study also showed that an early rehabilitation program did not increase postoperative complications. We concluded that an early rehabilitation program or intensive instruction program only by a well-trained physical therapist or physiatrist was beneficial to postmastectomy patients in regaining the function and range of shoulder motion, and significantly better in a rehabilitation group.  相似文献   
43.
Systemic lupus erythematosus (SLE), a complex multigenic disease, is a typical antibody-mediated autoimmune disease characterized by production of autoantibodies against a variety of autoantigens and immune complex-type tissue inflammation, most prominently in the kidney. Evidence suggests that genetic factors predisposing to aberrant proliferation/maturation of self-reactive B cells initiate and propagate the disease. In SLE-prone New Zealand Black (NZB) mice and their F1 cross with New Zealand White (NZW) mice, B cell abnormalities can be ascribed mainly to self-reactive CD5+ B1 cells. Our genome-wide scans to search for susceptibility genes for aberrant activation of B1 cells in these mice showed evidence that the gene, Ltk, encoding leukocyte tyrosine kinase (LTK), is a possible candidate. LTK is a receptor-type protein tyrosine kinase, belonging to the insulin receptor superfamily, and is mainly expressed in B lymphocyte precursors and neuronal tissues. Sequence and functional analyses of the gene revealed that NZB has a gain-of-function polymorphism in the LTK kinase domain near YXXM, a binding motif of the p85 subunit of phosphatidylinositol 3-kinase (PI3K). SLE patients also had this type of Ltk polymorphism with a significantly higher frequency compared with the healthy controls. Our findings suggest that these polymorphic LTKs cause up-regulation of the PI3K pathway and possibly form one genetic component of susceptibility to abnormal proliferation of self-reactive B cells in SLE.  相似文献   
44.
Summary.  We have evaluated PCR–RFLP as a practical method for rapid typing of enteroviruses causing aseptic meningitis in Korea. Through blind examination of 80 clinical isolates from patients with aseptic meningitis, we have compared the results of conventional serotyping with PCR–RFLP based genotyping, which was developed for this study. Among the 80 case isolates, which had been previously typed by routine neutralization test, only 42 cases (52.5%) were matched with typing by PCR–RFLP. The result clearly demonstrated that the enterovirus serotype does not coincide with the genotype. Therefore, the classification of enteroviruses by genotyping with PCR–RFLP, although rapid and simple, may be complicated by regional or seasonal differences. However, the PCR–RFLP method developed in this study is applicable to the epidemiological study of enteroviruses when regional or seasonal differences exist, and is useful in identifying the source of an infection. Received August 6, 2001; accepted April 15, 2002 Published online July 10, 2002  相似文献   
45.
A rapid, selective and very sensitive ion-pairing reversed-phase HPLC method was developed for the simultaneous determination of trimebutine (TMB) and its major metabolite, N-monodesmethyltrimebutine (NDTMB), in rat and human plasma. Heptanesulfonate was employed as the ion-pairing agent and verapamil was used as the internal standard. The method involved the extraction with a n-hexane-isopropylalcohol (IPA) mixture (99:1, v/v) followed by back-extraction into 0.1 M hydrochloric acid and evaporation to dryness. HPLC analysis was carried out using a 4-microm particle size, C18-bonded silica column and water-sodium acetate-heptanesulfonate-acetonitrile as the mobile phase and UV detection at 267 nm. The chromatograms showed good resolution and sensitivity and no interference of plasma. The mean recoveries for human plasma were 95.4+/-3.1% for TMB and 89.4+/-4.1% for NDTMB. The detection limits of TMB and its metabolite, NDTMB, in human plasma were 1 and 5 ng/ml, respectively. The calibration curves were linear over the concentration range 10-5000 ng/ml for TMB and 25-25000 ng/ml for NDTMB with correlation coefficients greater than 0.999 and with within-day or between-day coefficients of variation not exceeding 9.4%. This assay procedure was applied to the study of metabolite pharmacokinetics of TMB in rat and the human.  相似文献   
46.
The occurrence of P fimbriae in a total of 222 uropathogenic Escherichia coli (UPEC) strains was investigated. Out of the total, 31 (14%) were P fimbriated. Of 24 pyelonephritogenic E. coli strains, three (13%) with P fimbriae occurred in children with clinical pyelonephritis, and of 198 E. coli strains 29 (15%) occurred in children with cystitis. Prevalence of P fimbriae of E. coli strains was found to be quite similar in patients with cystitis and pyelonephritis  相似文献   
47.
本文采用间接ELISA法检测了11株抗B-CLL患者IgM腹水和杂交瘤上清McAb的相对亲和力。结果提示,各株McAb结合抗原的相对亲和力不同。根据50%最大结合浓度分为两组。其中4株杂交瘤上清McAb与纯化腹水McAb测得结果基本吻合。实验结果为合理地选用这些单抗提供了重要依据。  相似文献   
48.
初三学生成就动机与学业成绩的关系研究   总被引:2,自引:1,他引:2  
编制中学生成就动机量表 ,考察 2 86名初三学生的成就动机状况。运用逐步回归分析探讨成就目标、归因方式、自我效能与学业成绩的关系 ,并对成就目标进行自我效能和归因方式的回归分析。结果表明 :影响初三学生学业成绩的主要成就动机因素是自我效能、表现目标、能力归因和掌握目标 ,努力归因、运气归因和自我效能是影响初三学生成就目标的主要因素 ,客观因素归因也会影响表现目标。对研究结果进行本土化思考 ,建构中学生成就动机的理想模型  相似文献   
49.
BACKGROUND: Like other herpes viruses, latent Epstein-Barr virus (EBV) infection can be reactivated to lytic replication. Reactivation can be achieved by treatment with various reagents, including tetradecanoyl phorbol acetate (TPA) and Ca2+ ionophores. Relatively little is known about the physiological factors related to reactivation of EBV. Previous studies have demonstrated that G0/G1 cell cycle arrest is associated with EBV activation, and that hypoxic conditions can induce cell cycle arrest. In the present study we investigated the effect of hypoxia on reactivation of EBV. OBJECTIVE AND METHODS: Hypoxic culture conditions were established and the expression of Zta protein and the number of EBV DNA copies were measured in B95-8 cells maintained under these conditions. RESULTS: Hypoxia treatment not only increased the expression of the EBV immediate-early protein Zta (which mediates the switch between the latent and lytic form of infection), but also increased the number of EBV DNA copies in B95-8 cells. CONCLUSIONS: EBV in latent infection can be activated to lytic infection by hypoxia treatment.  相似文献   
50.
目的: 观察非选择性一氧化氮合酶(NOS)抑制剂NG-硝基-L-精氨酸(L-NA)对急性肺损伤大鼠肺线粒体功能的影响,并探讨其改善急性肺损伤的作用机制。方法: 将SD大鼠随机分为空白对照组、急性肺损伤组、L-NA治疗组,采用舌静脉注射脂多糖(LPS)复制大鼠急性肺损伤模型,于大鼠急性肺损伤3h后给L-NA治疗3h,断头放血处死大鼠,迅速取出肺脏,匀浆器混匀后,低温差速离心法提取肺线粒体,测定线粒体总ATP酶、超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)、总一氧化氮合酶(T-NOS)、诱生型一氧化氮合酶(iNOS)、结构型一氧化氮合酶(cNOS)的活性,以及线粒体肿胀度、膜流动性和线粒体一氧化氮(NO)、丙二醛(MDA)含量;电镜观察大鼠肺线粒体超微结构的改变及治疗药对此改变的影响。结果: 在大鼠内毒素性急性肺损伤后,肺脏组织中线粒体表现为肿胀、膜流动性降低,线粒体中的T-NOS和iNOS活性显著升高,线粒体NO生成明显增加,而cNOS活性无明显变化;线粒体总ATP酶、SOD、GSH-Px活性均明显下降,线粒体MDA含量明显升高。急性肺损伤3h给予L-NA治疗3h,与急性肺损伤组相比,一氧化氮合酶活性有所改变,NO生成显著下降,总ATP酶、SOD、GSH-Px活性均显著升高,MDA含量下降。电镜结果显示内毒素性急性肺损伤后肺脏组织细胞水肿,线粒体肿胀、嵴断裂、溶解、消失;L-NA能改善内毒素性急性肺损伤引起的细胞水肿、线粒体肿胀和空泡化。结论: L-NA能明显抑制急性肺损伤后线粒体一氧化氮合酶活性,减少NO生成,改善线粒体能量供应,增加线粒体抗氧化作用,从而减轻急性肺损伤。  相似文献   
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