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91.
白细胞介素-13功能研究进展 总被引:5,自引:0,他引:5
白细胞介素-13主要由活化的Th2(CD4^ )细胞分泌,诱导单核巨噬细胞分化及延长寿命;促进MHC-Ⅱ,CD23表达;抑制炎性和趋化因子产生;诱导B细胞增殖,活化,刺激IgM,IgG的产生和重链的转换;使血管细胞粘附分子-1表达;抑制人类免疫缺陷病毒(HIV)复制;间接诱导巨噬细胞和NK细胞参与抗肿瘤作用。在变态反应性疾病和哮喘中引起呼吸道高反应性,嗜酸粒细胞性炎症,粘液分泌过多,基膜纤维化等,其受体是与IL-4Rα形成功能复合体而发挥作用。IL-13信号转导途径除了JAK/STAT6以外,尚有IRS-1,Fes,磷酸激酶,BCL-6/SOCS等途径。 相似文献
92.
Objective: To reveal the relationship between the biological characteristics of pathogen and the pig-to-human spread of the epidemic and infectious disease in 1998 in East China. Methods: Epidemiological survey, pathological examination of pigs and patients, and pathogen isolation were performed. Results: The disease had a character of quick onset, serious symptoms, short course and high mortality. The clinical manifestations and pathological changes of the disease were high fever, sometimes with nausea, vomiting and diarrhea, then might develop to myositis, fascitis, DIC, multiple organ failure, shock and usually died in 2-3 d. Among 25 patients, 16 manifested clinically as streptococcal toxic shock syndromes and 9 streptococcal meningiocephalitis syndrome. The mortality was 81.25% and 11.11% respectively. Pathogenic bacteria isolated from diseased pigs and patients were found to have some common characteristics in morphology, staining and biological characters. Conclusion: The pathogen isolated from the blood of patients and pigs were identified as streptococci. 相似文献
93.
目的:用目的基因随机表位库方法寻找葡激酶(straphylokinase SAK)的显性表位。方法:①SAK免疫BALB/C小鼠,免疫亲和层析纯化抗血清后,抗SAK抗体用生物素标记;②构建SAK随机表位肽库,随机挑取12个独立克隆测序,分析库DNA片段的分布和碱基含量情况;③以多抗为靶蛋白用克隆原位杂交法筛选肽库;④构建SAK的缺失突变体mSAK,Western blot分析mSAK的免疫反应性。结果:①筛选肽库得到一个由19个氨基酸组成的免疫显性表位区,命名为A1区;②mSAK不能与抗SAK多抗反应。结论:用简便、有效的方法筛选得到了SAK的一个表位A1区,初步确定A1区是SAK引起免疫反应的重要区域。 相似文献
94.
Chuan-ling Qiao Kang-zhen Yu Yong-ping Jiang Yong-qing Jia Guo-bin Tian Ming Liu 《Avian pathology》2003,32(1):25-31
Inactivated whole avian influenza virus (AIV) vaccine provides protection against homologous haemagglutinin (HA) subtype virus, but poor protection against a heterologous HA virus. Moreover, it induces chickens to produce antibodies to cross-reactive antigens, especially nucleoprotein, which is limits AIV serological surveillance. In this study, a recombinant fowlpox virus co-expressing HA (H5 subtype) and NA (N1 subtype) genes of AIV was evaluated for its ability to protect chickens against intramuscular challenge with a lethal dose of highly pathogenic (HP) AIV. Susceptible chickens were also vaccinated by wing-web puncture with the parent fowlpox vaccine virus. Following challenge 4 weeks later with HPAIV, all chickens vaccinated with recombinant virus were protected, while the chickens vaccinated with either the unaltered parent fowlpox vaccine virus or unvaccinated controls experienced 100% mortality following challenge. This protection was accompanied by the high levels of specific antibody to the respective components of the recombinant vaccine. The above results showed that rFPV-HA-NA could be a potential vaccine to replace current inactivated vaccines for preventing AI. 相似文献
95.
宫腔镜电切术在宫颈疾病中的应用 总被引:3,自引:1,他引:2
目的探讨应用官腔镜电切术治疗宫颈病变的临床效果。方法2002年1月~2003年6月,应用宫腔电切镜切除359例各类宫颈病变。结果359例均在门诊一次完成手术,手术时间5~15min,术中出血2-10ml。术后病理诊断慢性官颈炎332例,宫颈上皮内瘤样病变(cervical intraepithelial neoplasia,CIN)Ⅰ~Ⅱ级26例,CINⅢ级1例。335例随访2~12个月,平均9个月。术后2个月308例慢性富颈炎一次性治愈率98.7%(304/308);237例随访1年宫颈糜烂、宫颈息肉及宫颈肥大未复发;27例CIN术后随访6~12个月未显示CIN病变。结论宫腔镜电切术治疗宫颈病变,疗效肯定,并发症少,值得推广。 相似文献
96.
本文报道了169例中、老年普外科非急诊入院患者营养状况调查,多参数指标包括人体测量和实验室检查。结果显示40%患者有不同程度的营养不良。120例(71%)患者在8项调查指标中,有2~6项异常。按消化道和非消化道疾病进行比较,体重身高指数(WT/HT)、上臂周径(AMC)在中年组有显著差异(P<0.05)。 相似文献
97.
J R Dimmock K M Advikolanu H E Scott M J Duffy R S Reid J W Quail Z Jia R A Hickie T M Allen J M Rutledge 《Journal of pharmaceutical sciences》1992,81(12):1147-1152
Mannich bases were synthesized and converted to the corresponding arylhydrazones. X-ray analysis of a ketone (1a) and a hydrazone (4d) revealed structural features of interest. All of the compounds showed cytotoxicity toward murine lymphocytic leukemia L1210 cells in the 4.9-25.0-microM range. The correlation coefficients generated by plotting the IC50 values (the concentrations of compounds that inhibit the growth of tumors by 50%) of some hydrazones against certain electronic, hydrophobic, and steric constants of the aryl substituents indicated only weak correlations. A few ketones and hydrazones displayed significant cytotoxicity to the WiDr human colon cancer cells, and these derivatives, especially the ketones, may serve as prototypes for future drug development. The KB tumor (a human epidermoid carcinoma of the nasopharynx) was somewhat refractory to selected compounds. In an in vitro assay conducted by the National Cancer Institute and involving approximately 53 tumor cell lines originating from eight neoplastic diseases, 65% of the compounds showed some selectivity toward one or more groups of cancers, principally leukemia, melanoma, and colon cancer. The bioevaluation of the ketones and hydrazones against the L1210, WiDr, and KB tumors, as well as evidence from proton nuclear magnetic resonance studies did not support the suggestion that hydrazones may be prodrugs of the corresponding ketones. 相似文献
98.
小鼠实验性糖尿病对胰腺腺泡细胞形态学的影响 总被引:1,自引:0,他引:1
为了探讨实验性糖尿病对胰腺腺泡细胞的影响,我们用四氧嘧啶对小鼠建造糖尿病模型。8wk后,取小鼠胰尾组织作光镜和电镜观察。结果:实验性糖尿病小鼠胰腺内部分腺泡细胞萎缩、细胞排列松散,并有大量慢性炎症细胞浸润。电镜下可见粗面内质网扩张,线粒体嵴紊乱、空泡变性,胞浆内出现髓样小体,酶原颗粒减少。表明实验性糖尿病对小鼠胰腺腺泡细胞的结构有一定的损害作用,进而使胰腺外分泌部的分泌功能受到影响。 相似文献
99.
100.
T Jia 《中华神经精神科杂志》1992,25(2):103-5, 127
40 patients of stroke were studied. The results showed that in Cerebral hemorrhage the correlation between ascending Growth hormone (GH) of CSF and insulin of serum was negative, but the positive correlation between ascending GH (CSF) and hyperglycemia. In patients of cerebral thrombosis the results of values above were no correlation. The pathological significance in such cases was discussed. 相似文献