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51.
AIM:To establish the monoclonal antibody against human B lymphocyte stimulator (hBLyS) by DNA immunization and analyse its characterization. METHODS:The 858 bp DNA fragment of hBLyS was cloned into pcDNA3 plasmids. The cloned insert was identified by both sequence analysis and double digestion of the recombinant plasmid with restriction enzymesXho Iand EcoR I. After the splenocytes from BALB/c mice immunized with the recombinant plasmid of pcDNA3/hBLyS were fused with myeloma cells SP2/0,the hybridoma which can produce monoclonal antibodies against hBLyS were obtained. The specificity of anti-BLyS monoclonal antibody from hybridoma was verified by ELISA, Western blot and flow cytometry. RESULTS:The recombinant mammalian cell expression vector of pcDNA3/hBLyS was constructed,the sequence of the insert gene was identified to be the sequence encoding hBLy S antigen. The culture supernatants of hybridoma 9c10 were tested to be the monoclonal antibody with specificity against hBLyS on human peripheral blood CD3+T cell activated by hIFN-γ by ELISA,Western blot and flow cytometry.CONCLUSION:The monoclonal antibodies against hBLyS with high activity and specificity have been established successfully, and will be an useful tool in the studies of relationship between hBLyS and human autoimmunity diseases. 相似文献
52.
AIM:To examine the effects of recombinant human hepatocyte growth factor(rhHGF) and native calf HGF(cHGF) on SMMC-7721 human hepatocellular carcinoma(HCC) cell line. METHODS:Human HCC cell line culture, photometric assay, and flow cytometric assay were used in this study .RESULTS:A similar type of dose-dependent cell growth inhibition effect on SMMC-7721 human HCC cells by rhHGF(5-20 μg/L) as well as by cHGF(25-100 mg/L) had been found, with the maximal effect at the highest concentration used. Approximately over 50% of the cells treated with rhHGF(5 μg/L, 10 μg/L, 20 μg/L) accumulated in the quiescent G0/G1 phase of the cell cycle over incubation periods for 3 d. CONCLUSION:The growth of SMMC-7721 human HCC cells was strongly inhibited by both rhHGF and cHGF. This might be because the cells exposed to HGF became arrested in the G0/G1 phase. 相似文献
53.
AIM: To observe the effect of Jiawei Sini Decoction (JWSND) on glucocorticoid receptor (GCR) in thymocytes of chronic psychological stress rats. METHODS: The rats were randomly divided into 4 groups, control group (C), model group (M), group treated by JWSND C1, group treated by ginsenosides C2. The number of thymocyte GCR sites and the GCR nuclear thanslocation rate were detected by radioimmunoassay. RESULTS: Compared with the control group, in the model group, the thymocyte weight index lowered significantly ( P<0.05 ), and the GCR nuclear thanslocation rate was increased significantly ( P<0.01 ), but the number of thymocyte GCR sites was unchanged. Compared with the model group, thymus gland weight indexes of C1 and C2 were increased significantly ( P<0.05 ), while the GCR nuclear thanslocation rate lowered significantly ( P<0.01 ). Moreover, no significant difference was found in all indexes between C1 and control group. CONCLUSION: The inhibitory effect of glucocorticoid on the thymus could be significantly reversed by JWSND via suppressing the thanslocation of GCR from cytoplasm to nucleus in chronic psychological stress rats. 相似文献
54.
AIM: To observe the direct effects of peripheral blood monocytes/macrophages (MO/MAC) on renal tubular epithelial cells (RTEC),and further probe into the possible mechanisms. METHODS: Conditioned medium(M-CM) of human peripheral blood MO/MAC was collected and added to HK-2,a human renal proximal tubular cell line.After incubation with M-CM for 24 hours,HK-2 cells were detected for DNA synthesis by [3H]-TdR incorporation,osteopontin (OPN) and α-smooth muscle actin (α-SMA) expression by Western blot,and fibronectin(FN) secretion by ELISA.Furthermore,anti-TGFβ1 neutralizing antibody and interlukin-10(IL-10) were used separately to antagonize the effects of M-CM on HK-2 cells. RESULTS: ①DNA synthesis,α-SMA expression and FN secretion were all increased in HK-2 cells when incubated with M-CM.②When adding with anti-TGFβ1 neutralizing antibody (5 mg/L) in the M-CM,the degree of upregulation of α-SMA and FN in HK-2 cells was much lower than that stimulated by M-CM alone.③M-CM added with IL-10 (20 μg/L) had a weaker ability to induce the increasing in α-SMA expression and FN excretion in HK-2 cells, compared with M-CM itself alone.M-CM from MO/MAC preincubated with IL-10 caused a lower upregulation of α-SMA expression in HK-2 cells than M-CM from non-preincubated MO/MAC. CONCLUSION: MO/MAC can directly induce proliferation,transdifferentiation and extracellular matrix secretion in RTEC.TGFβ1 and proinflammatory cytokines secreted by MO/MAC might be involved in the aboveeffects. 相似文献
55.
56.
苹果矮化砧木‘辽砧2号’选育 总被引:2,自引:0,他引:2
从1135系的助列涅特与M9杂交实生苗中选出优良苹果矮化砧木—辽砧2号(原代号80-1-6),经过22年田间观查和区试鉴定,其矮化性、早果性、丰产性、生根性与M26相近,适应性强于M26,以其为中间砧的富士树栽后6年进入盛果期,平均株产为23.5kg,同龄M26为17.2kg;8年生树冠积为4.07m3,同龄M26为4.58m3,树体存活率较M26高55%,平均每666.7m2产量1000kg以上;与基砧山定子和生产上主栽的富士系、元帅系、国光系等品种亲和性良好,以自根砧和中间砧方式利用均可。 相似文献
57.
CHEN Chun-yan JIA Ji-hui PAN Xiang-lin ZHANG Qi WANG Juan-dong ZHOU Ya-bin 《园艺学报》2004,20(7):1183-1186
AIM: To study the signal transduction pathway of apoptosis initiation induced by homoharringtonine in HL-60 cells. METHODS: After establishing the model of apoptosis initiation induced by homoharringtonine in HL-60 cells, at the point of apoptosis initiation, molecular caspase-3, Bcl-2, Bax and Fas/FasL were measured with flow cytometry and transmission electron microscope. ERK2 and P38 expression in HL-60 cells were detected by using immunohistochemistry. RESULTS: The model of apoptosis initiation induced by homoharringtonine was established in HL-60 cells. At the point of apoptosis initiation, upregulation of caspase-3 and decrease in Bcl-2/Bax were observed. However, the expression of Fas/FasL did not significantly change. ERK2 expression decreased and P38 expression increased. CONCLUSIONS: Caspase-3, Bcl-2, Bax and mitogen activated protein kinase pathways were involved in signal transduction of apoptosis initiation induced by homoharringtonine in HL-60 cells. 相似文献
58.
AIM: To further investigate the role of PKARⅠβ in the growth-promoting effects of shuang long Jiegu pill (SLJGP), a Chinese medicine, on cultured osteoblasts. METHODS: pcDNA- antiPKARⅠβ, a recombinant expressing the antisense sequence of PKARⅠβ, was constructed and transformed HFOB1.19 by lipofectin. MTT was undertaken to assess the cell growth with the treatment of high dosage of SLJGP containing serum. RESULTS: Antisense gene blocked the growth-promoting effects of SLJGP containing serum on HFOB1.19. CONCLUSION: The function of SLJGP is closely related to cAMP-dependent protein kinase A. 相似文献
59.
瘦肉型猪(PIC344)精液碱性磷酸酶的分离纯化及部分性质研究 总被引:2,自引:0,他引:2
用正丁醇抽提、硫酸铵分级沉淀、DEAE SepharoseFF和SephacrylS 200柱层系,从瘦肉型猪(PIC344)精液中提取出碱性磷酸酶。纯化倍数11 46,比活为81 23U/mg蛋白。提取液经PAGE和SDS PAGE检测,呈现一条带。该酶相对分子质量为90 12KD,亚基分子质量为48 41KD,该酶为两个相同亚基组成。等电点为8 19,最适pH值9 5,最适温度为40℃,以磷酸苯二钠为底物测得Km值为3 98×10-4mol/L。经分析,Cu2 、Cd2 为酶的抑制剂,Ni2 、Ca2 、Mg2 为该酶的激活剂。选用CuSO4、Cd(NO3)2作酶的抑制类型判断,结果表明,CuSO4为非竞争性抑制,抑制常数为1 32×10-3mol/L,Cd(NO3)2为竞争性抑制,抑制常数为3 33×10-4mol/L。 相似文献
60.
酵母铬与L-肉碱对蛋鸡生产性能及脂质代谢的影响 总被引:6,自引:0,他引:6
选用21周龄海兰褐壳蛋鸡288只,随机分为9组,每组32只,采用3×3(铬×L-肉碱)2因子3水平有重复交叉试验设计,预试2周后,在玉米-豆粕型日粮的基础上添加不同水平的酵母铬(以铬计:0、400、600μg/kg)与L-肉碱(0、50、100mg/kg),以饲喂基础日粮组为对照组,用以研究二者对蛋鸡生产性能及脂质代谢的影响,并初步探讨二者的互作效应,试验期7周。结果表明:600μg/kg铬或100mg/kgL-肉碱对脂质代谢多数指标效果显著(P<0.05或0.01);二者同时添加对蛋黄胆固醇、肝脏甘油三酯及腹脂率等均产生显著互作效应(P=0.0003~0.0500),且400μg/kg铬和100mg/kgL-肉碱混合添加对降低蛋黄胆固醇比其它各组均表现出优势,400μg/kg铬和50mg/kgL-肉碱混合添加对降低腹脂率比其它各组均表现出优势。铬或(与)L-肉碱在降低蛋鸡肝脂、腹脂及蛋黄胆固醇的同时并未影响蛋鸡的生产性能。 相似文献