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21.
AIM:To investigate the effects of FK506 on anti-glomerular basement membrane(GBM) nephritis in rats. METHODS: Anti-GBM nephritis model was elaborated by rabbit anti-rat GBM antibody injection in SD rats in this study. The rats were divided into three groups: FK506 treated group(0.5 mg·kg-1·d-1, sc), untreated nephritis control group and normal control group. FK506 was administered daily six hours after injection of anti-GBM IgG. All the rats were observed urinary protein at the 4th day, the 14th day and the 21st day. At the same time, the kidney specimens were collected, and T cell transforming function was also monitored.RESULTS:Rats injected with rabbit anti-GBM Ab developed heavy proteinuria by 4 days, and serum creatinine and serum urea appeared which kept on the rising. Glmerular hypercellularity, crescents, and protein casts were observed in nephritic rats. By electron microscopy, the thickening of GBM and loss of foot processes were seen. T cell transforming function was higher than normal. But, all pathological changes obviously turned for the better in FK506 treated group. CONCLUSION:FK506 could inhibit the progression of rat anti-GBM nephritis. 相似文献
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苏云金芽孢杆菌cry基因在大肠杆菌中表达产物和生物活性 总被引:4,自引:0,他引:4
研究了几种Bt cry基因于大肠杆菌(Escherichia coli)中表达产物在pH 10.0的50mmol/L碳酸钠和20mmol/L乙醇胺溶解液中的溶解性 ,发现同样的Cry蛋白在碳酸钠中的溶解度大于乙醇胺。通过胰蛋白酶消化 ,明确Cry1Ca7、Cry1Ia8酶解产物为 38kD多肽 ;Cry1Ie1、Cry1Cb2、Cry2Ab4酶解产物为 41kD多肽 ;Cry1Ac酶解产物为60kD多肽。采用FPLC层析方法对 6种原毒素及其酶解后得到的毒素多肽进行了分离纯化 ,比较了原毒素和毒素的杀虫活性的差异。其结果表明 ,Cry1Ac的原毒素和毒素对棉铃虫初孵幼虫的校正死亡率均为 100% ,Cry2Ab4的原毒素的毒力高于其酶解毒素。 相似文献
24.
AIM:To investigate the effect of lansoprazole on gastric ulceration in rats. METHODS:Using the gastric ulcer model induced by hemorrhagic shock, restraint water-immersion stress and pylorus-ligature, the protective effect of lansoprazole (iv) on gastric ulceration was observed. RESULTS:Pretreatment with lansoprazole (7.5-60 mg/kg) significantly inhibited the formation of gastric ulcer in the three models in a dose-dependent manner. The autiulcer efficacy of lansoprazole was similar to that of omeprazole in the equal dose, but stronger than that of omeprazole for ulcer induced by water-immersion stress.CONCLUSION:The intravenously administered lansoprazole inhibited formation of experimental gastric ulcer in rats. 相似文献
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26.
AIM: To study the effect and mechanism of chlorophyllin (CHL) inhibiting HT29 cells. METHODS: IC50 value and growth curve of HT29 cells were detected with MTT method. Apoptosis was detected with Wright-Giemsa staining, FCM and DNA electrophoresis. Telomerase was detected by PCR-ELISA, and protein and mRNA expression of COX-2 gene were detected through RT-PCR and Western blot. RESULTS: CHL inhibited the growth of HT29 in a dose-dependent manner. CHL blocked HT29 cells in G1 phase but did not induce apoptosis. Different concentration of CHL inhibits the expression of telomerase and COX-2 in HT29 cells. CONCLUSION: CHL inhibited the growth of HT29 cells by inhibiting the expression of telomerase and COX-2 and blocking cells in G1 phase. 相似文献
27.
DING Gui-xia ZHANG Ai-hua HUANG Song-ming WU Yuan-jun FEI Li GUO Mei CHEN Rong-hua 《园艺学报》2004,20(10):1754-1758
AIM: To investigate the role of NF-κB/IκB signal pathway in the regulation of cyclooxygenase-2 (COX-2) expression in human mesangial cells (HMC). METHODS: The PGE2 concentration in supernatants of HMC was measured by radioimmunoassay. COX-2 mRNA and protein expression were determined by RT-PCR and Western blot. Electrophoretic mobility shift assay (EMSA) and Western blot were used to detect the activity of NF-κB and degradation of IκB. RESULTS: IL-1β significantly upregulated COX-2 expression and PGE2 production in HMC. Significant up-regulation of NF-κB activation, nuclear translocation of p65 subunit, and degradation of IκB α and IκB β were observed in IL-1β-induced HMC. CONCLUSION: Expression of COX-2 in IL-1β-induced HMC is mediated by NF-κB/IκB signal pathway. 相似文献
28.
引诱剂在综合防治桔小实蝇作用中的评估 总被引:5,自引:1,他引:5
以使用引诱剂为主 ,坚持在杨桃园挂引诱笼 2 - 3年后 ,大量降低田间桔小实蝇BactroceradorsalisHendel雄虫数量和卵的受精率 ,配合其它的综防措施 ,防效逐年提高。三个综防点试验实践表明 :杨桃每果虫口数 ,卵孵化率及受害果率大大降低 ,防效达 92 5%。对桔小实蝇的防治初见成效。 相似文献
29.
BsC3-41杀蚊幼制剂对蚊幼虫毒杀效果研究 总被引:2,自引:0,他引:2
通过以BsC3- 41杀蚊幼制剂对 3种蚊幼虫进行生物活性测定和野外灭蚊试验 ,结果表明 :该制剂对致乏库蚊CulexfatigansWiedemann的毒杀效果最好、对中华按蚊AnophelessinensisWiedemann次之、对白纹伊蚊AedesalbopictusSkuse的效果较差 ,2 4小时LC50值分别为 0 2 0 2 5 μg/ml、 2 5 363μg/ml和 5 9 730 2 μg/ml。野外水体灭蚊使用 3ml/m2 的浓度防治淡色库蚊效果可达 98 88%~ 1 0 0 0 0 % ,使用 1 0ml/m2 的浓度防治中华按蚊效果可达96 81 %~ 1 0 0 0 0 % ,使用 2 0 0ml/m2 的浓度防治白纹伊蚊效果达到 90 64%以上。 相似文献
30.
AIM: The effects of YIGU capsule on proliferation and IGF-I mRNA protein expressions in osteoblasts were studied. METHODS: (1) Forty 12-month old Sprague-Dawley female rats were divided randomly into four groups (YIGU capsule high dose group, medium dose group and low dose group; saline group), the drug-containing serum and control serum were prepared. (2) The new-born Sprague-Dawley rat osteoblasts were cultured with different YIGU capsule drug-containing serum at different concentrations and different exposure time. MTT method was used to observe proliferation of osteoblasts. (3) RT-PCR method was used to measure the relative IGF-I mRNA levels and ELISA method was used to measure IGF-I secretion at different exposure time. (4) ELISA method was used to measure IGF-I secretion at different exposure time. RESULTS: (1) Proliferation of osteoblasts was more than the control groups after 48, 72 and 96 h, respectively (P<0.01); (2) The relative IGF-I mRNA levels and IGF-I protein expression were higher than those in control group after 48, 72 and 96 h, respectively (P<0.01 or P<0.05). CONCLUSIONS: It was suggested that YIGU capsule drug-containing serum promoted proliferation, IGF-I mRNA and protein expression. These results may be parts of the mechanisms of YIGU capsule to prevent and treat osteoporosis. 相似文献