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991.
乙型、丙型肝炎DNA疫苗单次联合接种后小鼠的免疫应答 总被引:1,自引:1,他引:1
目的:观察由编码HBsAg与HCV-CE2抗原的两种重组真核细胞表达质粒制备的DNA疫苗联合接种BALB/c小鼠后,其施生行异性免疫应答的规律和相互影响。方法:应用上述2种DNA疫苗单次联合免疫小鼠,动态观察血中特生抗体水平;并完成稳定转染,表达相应抗原的SP2/0骨髓瘤细胞的建株,采用CTL杀伤活性体内诱生实验的方法建立观察DNA疫苗免疫保护与治疗泊动物模型。结果:两种DNA疫苗单次联合免疫小鼠 相似文献
992.
Antithyroperoxidase and antithyroglobulin antibodies in a five-year follow-up survey of populations with different iodine intakes 总被引:2,自引:0,他引:2
Li Y Teng D Shan Z Teng X Guan H Yu X Fan C Chong W Yang F Dai H Gu X Yu Y Mao J Zhao D Li J Chen Y Yang R Li C Teng W 《The Journal of clinical endocrinology and metabolism》2008,93(5):1751-1757
OBJECTIVE: In a follow-up study, we determined the prevalence, incidence, and natural course of positive antithyroperoxidase antibodies (TPOAbs) and antithyroglobulin antibodies (TgAbs) in the general population and examined the influences of iodine intake. DESIGN: The study was conducted in Panshan, Zhangwu, and Huanghua, regions with mildly deficient, more than adequate, and excessive iodine intake, respectively. Of the 3761 unselected subjects who were enrolled at baseline, 3018 participated in the 5-yr follow-up study. Serum TSH, TPOAb, and TgAb levels were measured. RESULTS: Among subjects in Panshan, Zhangwu, and Huanghua, the prevalence of positive TPOAbs was 11.23, 11.83 and 12.02%, respectively, whereas 11.23, 11.17, and 11.26% of subjects were TgAb positive, respectively. In the older population (> or =45 yr), TgAb-positive individuals were more frequent in Huanghua than Panshan and Zhangwu (P < 0.05). The 5-yr cumulative incidence of positive TPOAb was 2.08, 3.84, and 2.84% in Panshan, Zhangwu, and Huanghua, respectively, whereas 2.91, 3.64, and 5.07% of subjects were TgAb positive, respectively (P < 0.05), corresponding to the increase in iodine intake. Subjects who were TPOAb and/or TgAb positive at baseline developed thyroid dysfunctions more frequently than those without antibodies (14.44 vs. 3.31%, P < 0.01); their incidence of elevated TSH levels was 1.32, 8.46, and 15.38% in Panshan, Zhangwu, and Huanghua, respectively (P < 0.05). CONCLUSIONS: Subjects who were TPOAb and TgAb positive at baseline developed thyroid dysfunctions more frequently than seronegative subjects. High iodine intake was a risk factor for developing hypothyroidism in antibody-positive subjects. A constant exposure to excessive iodine intake increased the incidence of positive TgAb. 相似文献
993.
994.
目的探讨冠心病患者中肾动脉狭窄(ARAS)的患病率及其相关因素。方法228例冠脉造影患者同时行选择性双肾动脉造影检查,对临床资料和ARAS之间的关系进行单因素和多因素Logistic回归分析。结果228例患者中,ARAS患病率为19.7%;经冠脉造影证实的152例冠心病患者中,ARAS患病率为27.6%;51例冠心病合并颈动脉粥样斑块的患者中,ARAS患病率为49.0%。45例ARAS患者中,左肾动脉狭窄的患病率显著高于右肾动脉(P<0.05)。单因素分析表明,年龄、糖尿病、肾功能不全、颈动脉粥样斑块、冠心病是ARAS的预测因素。多元Logistic回归分析表明,仅年龄、颈动脉粥样斑块、冠脉三支病变是ARAS的独立预测因素。结论对于冠心病患者,尤其是年龄≥60岁及合并颈动脉粥样斑块的患者,冠脉造影后应常规行肾动脉造影,以便早期发现ARAS。 相似文献
995.
弓形虫感染对雄性小鼠睾丸细胞周期影响的实验研究 总被引:2,自引:0,他引:2
目的 研究弓形虫感染对雄性小鼠睾丸组织细胞周期的影响。方法 应用流式细胞术检测弓形虫感染10 3/ ml、10 4 / ml、10 6 / ml3个剂量组小鼠睾丸组织细胞周期,并设立生理盐水和环磷酰胺对照组。结果 不同剂量的弓形虫感染均可使小鼠睾丸组织细胞各时相的细胞百分数发生变化,并随着剂量的增加,G0 / G1 、S时相的细胞百分数明显减少,与阴性对照组比较差异有显著性(P<0 .0 5 )。G2 / M时相的细胞百分数逐渐增多,各剂量组与阴性对照组比较差异有显著性(P<0 .0 5 )。结论 弓形虫感染可能抑制小鼠睾丸细胞的DNA合成,可引起G2 期细胞阻滞,从而使细胞的有丝分裂延伸。 相似文献
996.
997.
分枝杆菌胞壁融合表达Ag85B-ESAT-6穿梭质粒的构建 总被引:4,自引:0,他引:4
目的 构建E coli BCG(BacilleCalmette Guerin)穿梭载体 ,在母牛分枝杆菌细胞壁融合表达结核分枝杆菌 (MTB)的分泌蛋白Ag85B ESAT 6。方法 用聚合酶链反应 (PCR)从MTB毒株H3 7Rv基因中扩增出结核分枝杆菌 190 0 0抗原 ( 19 ss)胞壁区及其上游调控元件基因 ,克隆入E coli BCG穿梭载体 pOLYG中 ,构建表达蛋白能嵌入细胞壁中的E coli BCG穿梭载体。用间接免疫荧光染色法观察该载体携带所构建的结核分枝杆菌分泌蛋白Ag85B和ESAT 6基因在母牛分枝杆菌宿主中的融合表达。结果 经测序证实所克隆的 19 ss基因序列正确 ,所构建的E coli BCG穿梭载体 (pCW )能完成在大肠杆菌和母牛分枝杆菌细胞之间的穿梭 ,经免疫荧光检查外源基因Ag85B ESAT 6可融合表达于分枝杆菌宿主表面。 结论 本方法可成功构建能够在分枝杆菌胞壁融合表达MTB分泌蛋白Ag85B ESAT 6的E coli BCG穿梭质粒 相似文献
998.
Maeda N Palmarini M Murgia C Fan H 《Proceedings of the National Academy of Sciences of the United States of America》2001,98(8):4449-4454
Jaagsiekte sheep retrovirus (JSRV) is the causative agent of ovine pulmonary carcinoma, a unique animal model for human bronchioalveolar carcinoma. We previously isolated a JSRV proviral clone and showed that it was both infectious and oncogenic. Thus JSRV is necessary and sufficient for the development of ovine pulmonary carcinoma, but no data are available on the mechanisms of transformation. Inspection of the JSRV genome reveals standard retroviral genes, but no evidence for a viral oncogene. However, an alternate ORF in pol (orf-x) might be a candidate for a transforming gene. We tested whether the JSRV genome might encode a transforming gene by transfecting an expression plasmid for JSRV [pCMVJS21, driven by the cytomegalovirus (CMV) immediate early promoter] into mouse NIH 3T3 cells. Foci of transformed cells appeared in the transfected cultures 2-3 weeks posttransfection; cloned transformants showed anchorage independence for growth, and they expressed JSRV RNA. These results indicate that the JRSV genome contains information with direct transforming potential for NIH 3T3 cells. Transfection of a mutated version of pCMVJS21 in which the orf-x protein was terminated by two stop codons also gave transformed foci. Thus, orf-x was eliminated as the candidate transforming gene. In addition, another derivative of pCMVJS21 (pCMVJS21DeltaGP) in which the gag, pol (and orf-x) coding sequences were deleted also gave transformed foci. These results indicate that the envelope gene carries the transforming potential. This is an unusual example of a native retroviral structural protein with transformation potential. 相似文献
999.
中药扶正抗癌方治疗中、晚期消化道肿瘤160例临床观察 总被引:1,自引:0,他引:1
14年来,以中药扶正抗癌方(自拟)治疗中、晚期消化道肿瘤160例,收到了较为满意的疗效。患者症状改善,血象升高,免疫指标提升,癌胚抗原含量下降.患者的体质增强,体重增加.其它疾病少发等,有的患者癌灶缩小,甚至消失,绝大多数的患者经治疗后生存期得以延长。 相似文献
1000.
Polyamines mediate androgenic stimulation of calcium fluxes and membrane transport in rat heart myocytes 总被引:3,自引:0,他引:3
The androgenic steroid hormone testosterone induced an early (less than 30-60 seconds) stimulation of endocytosis, hexose transport, and amino acid transport, monitored by the temperature-sensitive uptake of horseradish peroxidase, 2-deoxyglucose, and alpha-aminoisobutyrate, respectively, in rat ventricle cubes and acutely isolated ventricular myocytes. This stimulation was time- and concentration-dependent and was maximal at 10(-9) to 10(-8) M testosterone, consistent with androgen-receptor mediation. EGTA (2.5 mM), La3+ (1 mM), and verapamil (100 microM) ablated the hormonal response. The calcium ionophore A23187 (10 microM) induced an acute stimulation of endocytosis, amino acid transport, and hexose transport which was not further increased by testosterone (10(-8) M), suggesting a common effector pathway. Testosterone (10(-8) M) also evoked a rapid (less than 30 seconds) stimulation of 45Ca influx and efflux. Testosterone (10(-8) M) induced a rapid (less than 5 seconds) transient increase in ornithine decarboxylase (ODC) activity peaking (twofold to threefold) at 60 seconds, and an early (15 seconds) transient accumulation of polyamines peaking at 60 seconds in isolated myocytes. The specific, irreversible ODC inhibitor alpha-difluoromethylornithine (DFMO, 5-10 mM) blocked the testosterone-evoked increase in ODC activity and polyamine levels and the stimulation of Ca2+ fluxes, endocytosis, hexose transport, and amino acid transport. Putrescine (0.5-1 mM), the ODC product, reversed DFMO inhibition and restored the increase in polyamines, 45Ca fluxes, and Ca2+-dependent membrane transport processes. These results demonstrate that rapid, transient ODC-regulated polyamine synthesis is essential for androgenic stimulation of Ca2+ fluxes and membrane transport processes in ventricular myocytes. These findings support a model for signal transduction in which newly synthesized polyamines serve as intracellular messengers to regulate transmembrane Ca2+ movements, Ca2+-dependent membrane transport functions, and other Ca2+- and polyamine-sensitive processes in cardiac myocytes. 相似文献