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311.
AIM: To examine the expression of human endostatin in E.coli, produce its fusion protein antibody and observe its biological activity. METHODS: Endostatin gene was amplified by polymerase chain reaction,recombined with plasmid vector pGEX-2T and induced expression with IPTG.The protein activity was tested by endothelial cell proliferation inhibitory assay.Inclusion body crudely purified was used to generate polyclonal antibody to detect its expression at mouse's liver and kidney etc. RESULTS: The protein expressed was 20kD after digestion by thrombin,it appeared the anti-angiogenesis activity and Western blotting indicated the expression of endostatin in liver and kidney of mouse. CONCLUSION: The successful expression of human endostatin and the preparation of polycolonal antibody indicated its potential application in anti-angiogenesis therapy and diagnosis tumors. 相似文献
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ZHANG Yu-xia YU Lun-yin LIU Ming-qiu ZHANG Zheng-bin TANG Zhi-jiao XIA Dong WANG Ming 《园艺学报》2002,18(1):32-35
AIM:To investigate the protein expression of cyclin D2 and p16 in proliferation and differentiation of cultured cardiac myocytes.METHODS:One-day-old Sparague-Dawley rats were used. Cardiac myocytes(CM) were collected by a trypsin-dispersal method and cultured. Cell growth line and fluorescence activated cell sorting (FACS) were used to investigate the proliferation of CM. Ultra-thin sections were made to observe the ultrastructure of CM under transmission electron microscope. The expression of cyclin D2 and p16 in CM were measured using immunocytochemistry and image analysis.RESULTS:①Results of cell growth line and FACS analysis showed that cultured CM could proliferate in the first 3 cultured days, but the ability decreased quickly, concomitant with differentiation. CM was obseved quiescent in cell cycle three days later. The ultrastructure of CM showed the large amount of myofilaments and mitochondrion. ②The protein expression of cyclin D2 in 3,4,5 day CM group was 0.89 times(P<0.05),0.80 times (P<0.05) and 0.56 times (P<0.01) of that in 1 day group, respectively. The expression of p16 in CM was increased during the culture process, 2,3,4,5 day group were 1.63 times, 1.72 times, 1.99 times and 2.84 times (P<0.01) of that in 1 day group, respectively.CONCLUSION:Cultured neonatal rat cardiac myocytes could proliferate during the first 3 days after incubation, but the ability of proliferation decreased, from the fourth day, concomitant with differentiation. Cyclin D2 and p16 play the key roles in CM postnatal development. Downregulation of cyclin D2 and upregulation of p16 may induce CM differentiation. 相似文献
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CHEN Xiao-yin ZHANG Qun YANG Qin-he XIE Qiu-ling SHEN Qiang XU Yun-sheng 《园艺学报》2002,18(12):1529-1531
AIM: To examine the effect of traditional chinese medicine recipe, Taoren Honghua(semen persicae-flos carthami) decoction, on hyperlipidemia without symptom. METHODS: The plasma TC, TG, LDL, HDL, apolipoprotein(Apo) A, Apo Bof the patients with hyperlipidemia without symptom were measured using automatic analyzer (shimadiu CL-7200), the production of nitric oxide(NO) was detected by Greiss reaction, and SODactivity and MDAformation were examined using o-trihydroxy benzene and barbituric methotheds, respectively. RESULTS: After oral administration of Taoren Honghua decoction, the plasma levels of TC, TG, LDL, and MDAof the patients were markedly decreased, however, the plasma levels of ApoA, HDL, SODand NOwere significantly increased and almost no change was detected in the plasma level of Apo B. In control group, it was found that although the plasma level of TC, TG and LDL were decreased ( P<0.05 ) and ApoAas well as HDLwere increased, ApoB, SOD, MDA and NO production were all unchanged. CONCLUSION: The traditional chinese medicine recipe, Taoren Honghua decoction,has a significant therapeutic effect on patients with hyperlipidemia by removing blood stasis, promoting qi circulation and in turn reducing blood lipid level. 相似文献
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本文综述了对螟虫长距茧蜂的研究概况,包括该寄生蜂的主要生物学习性、对玉米螟自然寄生率及田间防治玉米螟效果等。 相似文献
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采用系统溶剂对南欧丹参Salvia sclarea L.花进行提取,以孢子萌发试验法、抑制菌丝生长速率法和盆栽试验系统测定了粗提物对植物病原真菌的生物活性。结果表明,石油醚为提取南欧丹参花活性成分的最佳溶剂。石油醚提取物在离体条件下能显著抑制多种供试真菌菌丝的生长,其对番茄灰霉病菌Botrytis cinerea的EC50值为77.20 μg/mL;对盆栽小麦白粉病Erysiphe graminis的防护效果为94.94%,治疗效果为84.21%。 相似文献
320.
实验室条件下系统研究了磷化氢(PH3)对储物害虫嗜卷书虱Liposcelis bostrychophila卵、各龄若虫和成虫的致死作用,并选用PH3间歇熏蒸以及PH3与气调交替处理等措施对嗜卷书虱进行处理,比较了不同处理措施对嗜卷书虱种群的控制效果。结果表明,PH3熏蒸处理对嗜卷书虱各虫态有不同的致死效果。对卵而言,24、72和120 h熏蒸处理的LC50分别为0.137、0.045和0.035 mg/L;而24 h熏蒸处理对若虫的LC50在4.285~7.364 μg/L之间,对成虫的LC50为20.404 μg/L;采用25 μg/L的PH3进行24 h熏蒸处理,间隔10 d后再分别进行第2次和第3次熏蒸处理,可以完全控制嗜卷书虱的发生。采用PH3 (12 μg/L)和气调(体积比例为35% CO2,1% O2,64% N2)交替处理能够延缓嗜卷书虱种群抗性的发展,交替处理3~5次可以完全控制嗜卷书虱的发生。 相似文献