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941.
YUAN Qing-feng XU Li-hong CHEN Jia-ping ZHOU Wen CHEN Shu-jie SI Jian-min 《园艺学报》2007,23(11):2265-2267
AIM: To explore the effect of recombinant human epidermal growth factor (rhEGF) on the ERK1/2 pathway and its safety in use when the proliferation of cultured FL cells (human amnion epithelial cells) were promoted by rhEGF.METHODS: FL cells were stimulated by rhEGF at various concentrations.The proliferation rate of FL cells was evaluated by MTT assay.Western blotting was used to detect phosphorylation of ERK1/2 (p-ERK1/2) and the change of Bcl-2 and P53 protein.RESULTS: The proliferation rate FL cells reached the maximum when the concentration of rhEGF was 10 μg/L (42.4%,P<0.01).Western blotting showed that the activity of p-ERK1/2 increased significantly when rhEGF ranged in 10 μg/L to 60 μg/L.Level of Bcl-2 was unchanged in each groups.Level of P53 decreased significantly when the concentration of rhEGF was 60 μg/L.CONCLUSION: It is safe when rhEGF presents in optimization concentration of 10 μg/L.The capability of apoptosis may be depressed when rhEGF is in larger dose. 相似文献
942.
喷施磷酸二氢钾对桃叶片和果实性状的影响 总被引:5,自引:1,他引:5
以不同成熟期的桃品种豫甜、豫香、秋甜、秋蜜红为试材,研究了喷施磷酸二氢钾对其叶片叶绿素含量、干鲜质量比及果实的可溶性固形物含量、可溶性糖含量、可滴定酸含量、维生素C含量等品质特性的影响。结果表明,喷施磷酸二氢钾能提高叶片中叶绿素含量、干鲜质量比和果实可溶性固形物含量、可溶性糖含量;对果实的可滴定酸含量、维生素C含量影响不明显;叶片喷施不同浓度和次数的磷酸二氢钾均可推迟桃果实成熟期;喷施清水和对照处理间叶片性状和果实品质差异不明显;喷施磷酸二氢钾浓度和次数以500mg/L3次效果最显著,以300mg/L3次最经济有效。 相似文献
943.
AIM: In order to study the effect of endogenous interferon system and Th1 response modes on hepatitis B virus infection, the 2′, 5′ oligoadenylate synthetase (2-5OAS), IL-2 and IL-12 were selected as the research parameters. METHODS: The activity of 2-5OAS in peripheral blood mononeuclear cells was determined by sensitive radioenzymatic assay. IL-2 and IL-12 were determined by ELISA. RESULTS: Compared to normal control, the 2-5OAS, IL-2 or IL-12 were not significantly changed (P>0.05) in the asymptomatic HBsAg carricer group. The 2-5OAS, IL-2 and IL-12 were significantly up-regulated (P<0.01) in the group of acute hepatitis, but in the groups of chronic hepatitis, liver cirrhosis and hepatocellular carcinoma, the 2-5OAS, IL-2, IL-12 were significantly down-regulated (P<0.05). Moreover, with the progression of patient′s conditions and with the complications of liver cirrhosis and hepatocellular carcinoma, the 2-5OAS, IL-2 and IL-12 decreased progressively, the 2-5OAS, IL-2, IL-12 were the lowest in guoups of liver cirrhosis and hepatocellular carcinoma (vs each groups of chronic hepatitis, P<0.05). CONCLUSION: The endogenous interferon system and Th1 response are significantly alterable in the different period of hepatitis B virus infection and among the different clinical types. The cellular immunity plays an important role in recovery from HBV infection. 相似文献
944.
AIM: To study the effect of late reperfusion on apoptotic cardiomyocytes in the risk area of acute myocardial infarctin in dogs. METHODS: The experiment was divided into three groups: sham operation group, acute myocardial infarction (AMI) group, and late reperfusion (LR) group. Apart from sham operation group, the other two groups were subjected to left anterior descending branch of coronary artery ligation. The acute myocardial infarction group was only subjected to ligation for 12 hours, late reperfusion group was subjected to ligation for 6 hours following by 6 hours of reperfusion. The cardiomyocyte apoptosis was measured by TUNEL assay. Immunohistochemistry and Western blotting analysis were used to detect the expression of Bcl-2 and Bax protein. RESULTS: The number of apoptotic cardiomyocytes in late reperfusion group was much less than acute myocardial infarction group (P<0.05), and increased significantily as compared with sham operation group (P<0.01). The expression of Bcl-2 protein was enhanced gently in late reperfusion group in contrast to acute myocardial infarction group, but no significant difference in the two groups (P>0.05) was observed, although it was much more in the two groups than that in sham operation group (P<0.01). The expression of Bax protein in late reperfusion group was much higher than that in sham operation group (P<0.01), and was lower than that in acute myocardial infarction group (P<0.05). CONCLUSION: Late reperfusion reduces cardiomyocyte apoptosis in the risk area of acute myocardial infarction. The mechanism may be that late reperfusion can decrease the expression of Bax protein. 相似文献
945.
The serine protease HtrA2/Omi is released from the mitochondrial intermembrane space following apoptotic stimuli.Once in the cytosol,HtrA2/Omi has been implicated in promoting cell death in caspase-dependent or caspase-independent pathway.On the other hand,HtrA2/Omi can refold and degrade misfolded proteins in the mitochondria during cell stress. 相似文献
946.
Kana Naito Yasuhiro Ishiga Kazuhiro Toyoda Tomonori Shiraishi Yuki Ichinose 《Journal of General Plant Pathology》2007,73(4):281-285
Flagellin in Pseudomonas syringae is a potent elicitor of defense responses including hypersensitive cell death in dicot plants. The oligopeptides flg22 consisting
of 22 conserved amino acids near the N-terminus of flagellins is reported to induce plant defense responses. Because glycosylation
of the central domain of flagellin affects its elicitor activity, we investigated whether any peptide sequence in addition
to flg22 is required for flagellin-induced hypersensitive reaction. A study of recombinant flagellin polypeptides indicated
that the N-terminal domain including the conserved flg22 is required for flagellin-induced hypersensitive cell death in Arabidopsis thaliana. 相似文献
947.
猪繁殖与呼吸综合征病毒感染对猪肺泡巨噬细胞外源性抗原加工递呈相关分子和共刺激分子的影响 总被引:1,自引:1,他引:1
采用定量竞争PCR技术对猪繁殖与呼吸综合征病毒(PRRSV)感染后不同时相猪肺泡巨噬细胞(PAM)中外源性抗原加工递呈相关分子SLA-DR、Ii链和SLA-DM分子及共刺激分子CD40、CD80、CD86的mRNA转录动态进行了定量检测。结果表明,PRRSV感染后PAM的SLA-DR mRNA转录水平在3、7和14 d下调,低于对照组;感染后3 d,Ii链、SLA-DM和CD40的mRNA转录水平极显著下调(P〈0.01);CD80和CD86mRNA转录水平也在感染后3 d明显下调(P〈0.05)。用流式细胞术检测PAM表面的SLA-DR抗原的结果表明,在感染后3 d短暂上升,7 d之后一直低于对照组。由此说明,PRRSV感染早期对猪肺泡巨噬细胞的外源性抗原加工和递呈功能产生显著影响,导致其外源性抗原递呈功能下降,进而影响机体的体液免疫应答。 相似文献
948.
949.
M. D. Pescovitz B. K. Book B. Aasted J. Dominguez R. Bullido I. Trebichavsky B. Novikov I. Valpotic J. Nielsen S. Arn D. H. Sachs J. K. Lunney P. C. Boyd J. Walker R. Lee N. Petrinec A. Saalmüller 《Veterinary immunology and immunopathology》1998,60(3-4):285-289
Among the 57 monoclonal antibodies analyzed within the T-cell group of the Second International Swine CD Workshop, one mAb fell within cluster T14a that included the CD6 standard a38b2 (No. 175). The new mAb MIL8 (No. 082) and a38b2 both precipitated from activated T-cells a 150 kDa monomeric protein. Staining patterns on the various cell types were similar. There was no inhibition of binding of either mAb to peripheral blood T-cells with the opposite mAb. The new mAb, MIL8, reacts with a separate epitope on porcine wCD6. 相似文献
950.
The kinetics of the production of interferon gamma (IFN-) in whole blood culture and its comparison with anti-listeriolysin O (ALLO) detection by ELISA were studied during oral infection of calves with Listeria monocytogenes. Culture filtrate antigen (CFA), listeriolysin O (LLO), and sonicated antigen (SA) were used to prime the peripheral blood mononuclear cells (PBMCs) and the plasma from orally infected calves. IFN- and ALLO appeared as early as day 7 of an oral infection. IFN- was detected earlier with LLO than with SA. The Max50 interleukin (IL-2) activity and IFN- estimated in the culture supernatant from PBMCs primed in vitro with different antigens of L. monocytogenes revealed high induction of IL-2 and IFN- by CFA, LLO and live antigen. IFN- assay and ALLO detection were used for testing cases of repeat breeding in dairy cattle. It appeared that detection of IFN- employing LLO can be used to diagnose listerial infections. 相似文献