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991.
不同培养液及血清浓度对绵羊孤雌生殖胚胎发育的影响 总被引:1,自引:0,他引:1
体外成熟的绵羊卵母细胞,经5 μmol/L A23187 5 min和2 mmol/L 6-DMAP 4 h激活后,分别在SOFaa、M-199两种培养液中进行培养,试验比较了SOFaa、M-199液分别添加BSA和不同浓度(10%、20%)胎牛血清对绵羊孤雌生殖胚体外发育的影响。M-199+FCS组的卵裂率显著低于SOFaa+BSA和SOFaa+FCS组(P<0.05),SOFaa+BSA组的囊胚率显著低于M-199+BSA、SOFaa+FCS、M-199+FCS三组(P<0.05);SOFaa+10% FCS与SOFaa+20% FCS组的卵裂率及囊胚率均无显著差异,M-199+10% FCS和M-199+20% FCS组的卵裂率及囊胚率间均无显著差异。结果表明:SOFaa比M-199更适合绵羊孤雌生殖胚体外发育,此外添加10%的FCS即可达到较好的培养效果。 相似文献
992.
XIA Yong ZHANG Yong LI Dong-ye LIN Li XU Rui-jin YU Hao DING Ru-yue YANG Yu CHEN Qing-zhi 《园艺学报》2007,23(1):49-52
AIM: To investigate the effects of celecoxib, a selective cyclooxygenase-2 inhibitor, on antioxidative capability and apoptosis of cardiac myocytes after myocardial infarction. METHODS: 24 New Zealand rabbits were divided into three groups randomly (8 in each group): sham-operated group (sham group), myocardial infarction group (MI group), celecoxib group (Cele group, 10 mg kg-1·d-1, qd, with the drugs gastric gavage for six weeks). The NO concentration, total antioxidative capability (T-AOC), the activity of constitutive nitric oxide synthase (cNOS) and inducible NOS (iNOS) in cardiac tissue homogenate, adjacent to the infracted area, were detected. The pathological changes were observed by light microscope and electron microscopy. The expressions of Bcl-2 and Bax protein in myocytes were observed using immunohistochemistry, and the degree of apoptosis were examined by TUNEL. RESULTS: Cardiac tissue in MI group presented interstitial edema, fibroplastic proliferation, inflammatory cellular infiltration, and vacuolar degeneration in cardiac myocytes. The results of electron microscopy showed that myocytes presented more changes caused by ischemic injury: widened interspace of myofibril, disordered myofibrillae, focal lysis of myofilament, ectasia of sarcoplasmic reticulum. In Cele group, the pathological changes were light, the NO-2/ NO-3 concentration, the activity of iNOS were lower (P<0.05), while the activity of cNOS and T-AOC were higher (P<0.05) than those in MI group. The expression rate of Bcl-2 protein in Cele group was higher than that in MI group, while the Bax was lower (P<0.01). The number of apoptotic myocytes was lower than that in MI group (P<0.01).CONCLUSION: Celecoxib decreases the number of apoptotic cardiomyocytes and increases the antioxidative capability after myocardial infarction. 相似文献
993.
994.
AIM:To investigate the role of caspase 3 inhibitor Ac-DEVD-CHO in caspase 3 signaling pathway and NF-κB activation induced by 10-hydroxycamptothecin (HCPT) in human breast carcinoma cells. METHODS:The cell growth inhibition was measured by MTT assay. Agarose gel electrophoresis was performed for detecting cell apoptosis. Western blotting was used for determining protein expression. DIG-EMSA was conducted to measure the DNA-binding activation of NF-κB. RESULTS:Caspase 3 inhibitor Ac-DEVD-CHO attenuated HCPT-induced apoptosis in human breast carcinoma. Ac-DEVD-CHO also suppressed the degradation of caspase 3 and IκBα,and arrested the activation of NF-κB. CONCLUSION:Caspase 3 inhibitor Ac-DEVD-CHO regulates the activation of caspase 3 and NF-κB,and attenuates apoptosis in Bcap37 cell line induced by HCPT. 相似文献
995.
CHEN Wei-zhen ZHANG Yong LU Han-ping LIANG Chang-sheng XIE Yao LIU Chang-zheng 《园艺学报》2007,23(10):2051-2053
AIM: To investigate the effect of 188Re labeled monoclonal antibody on prostatic specific membrane antigen 7E11C5.3,radioimmunotherapy for the treatment of human prostate cancer cell line LNCaP in vitro.METHODS: 188Re-7E11C5.3 was prepared by direct 2-mercaptoethanol reduction method.Labeling efficiency and radiochemical purity was measured by paper chromatography.Immunoreactive fraction was determined by linear extrapolation.Cytotoxicity to LNCaP cells was determined by MTT assay.RESULTS: The labeling yield of 188Re-7E11C5.3 was (93.16±2.18)%,the radiochemical purity was (95.62±0.48)%,and the immunoreactive fraction was (74.86±1.86)%.The inhibitory effect of 188Re-7E11C5.3 on cell proliferation of LNCaP cells was significantly higher than that of 188Re-mIgG or 188ReO-4.The 50% inhibitory doses (IC50) of 188Re-7E11C5.3,188Re-mIgG,and 188ReO-4 were (23.38±3.73)×107 Bq/L,(59.21±8.02)×107 Bq/L and (68.89±10.91)×107 Bq/L,respectively.CONCLUSION: 188Re-7E11C5.3 can effectively inhibit the growth of in vitro cultured prostate cancer cells and shows much potential for prostate cancer radioimmunotherapy. 相似文献
996.
川东南马尾松外生菌根苗及其抗铝性研究 总被引:1,自引:0,他引:1
采自西南地区分离的马尾松林常见的土著菌株松乳菇(Lactarius deliciosus 01,03)、彩色豆马勃(Pisolithus tinctorius 715)和模式种双色蜡蘑(Laccaria bicolor S238N)的基质纯培养物及液体纯培养物,分别按混合(Mix=Ld 01 Ld 03 Pt 715 Lb S238N)及单独接种的方式接种1月龄马尾松(Pinus massoniana)幼苗.菌根苗在不同pH土壤及铝胁迫条件下培育3个月后采样分析其生长和养分吸收特性.结果表明:4种接种方式均能有效形成菌根,显著增加幼苗的生物量,促进幼苗对N、P、K的吸收并显著(P<0.05)提高抗铝性;混合接种促进马尾松幼苗生长的效果较单独接种好,并且pH=6.1时,幼苗对K的吸收量最大,铝吸收量最少;pH=4.1时,幼苗对N、P的吸收效果最好,但对K的吸收和对铝的抗性最差. 相似文献
997.
LIU Ya-wei LIU Jing-hua XIE Ru-jia LI Zhi-jie WANG Guo-jun HUANG Shao TANG Jing ZHAO Ming-zhe SUN Xue-gang DENG Peng JIANG Yong 《园艺学报》2007,23(10):1937-1941
AIM: To study the effect of human FAT10 on the apopotosis of HEK293 cells using flag-tagged human FAT10 protein.METHODS: The fragment of FAT10 gene was cloned into the pcDNA3-flag vector,which was identified by PCR,enzyme digestion and sequencing.The reconstructed plasmids were transfected into HEK293 cells.The expression of introduced FAT10 in the normal cultured and starved cells was detected respectively by Western blotting.XTT assay and DNA ladder method were used to analyze the effect of FAT10 on the apoptosis of starved HEK293 cells.RESULTS: The reconstructed plasmids were highly expressed in HEK293 cells with different expression mode at the mormal cultured and starved state.The livability of starved FAT10 overexpressed HEK293 cells was significantly lower than that of normal cultured cells.DNA ladder was observed in the starved FAT10 overexpressed cells,but not in the normal cultured cells.CONCLUSION: The eukaryotic expressed plasmids of flag-tagged FAT10 were constructed successfully,and highly expressed in HEK293.Overexpressed FAT10 enhances the apoptosis in the starved HEK293 cells. 相似文献
998.
抗菌肽基因导入桑树获得抗病转基因植株 总被引:11,自引:2,他引:9
用携带抗菌肽基因的农杆菌处理桑子叶,在含有羧苄青霉素(Cb)400~500mg/L和卡那霉素(Km)20mg/L的MS培养基上,有32.4%的子叶产生了不定芽;66.5%的不定芽在含有Cb300mg/L和Km30~40mg/L的培养基中,正常生长成2~3cm高的新稍;新梢在含Cb50mg/L和Km10mg/L的生根培养基中有72.6%形成完整根系。3次转化共获得12个株系55株KmR植株。不同株系桑苗叶片DNA点杂交分析显示,7个株系有阳性杂交信号。KmR株系桑苗的抗病性测定显示,5个株系共14株桑苗对青枯病具有较强抗性. 相似文献
999.
不同生态区藏山羊的产绒性能研究 总被引:3,自引:0,他引:3
选择青藏高原四个不同的生态区,对藏山羊的产绒性能进行了研究,结果表明:西藏两个产区藏山羊的产绒量和绒的主要品质指标均高于四川两个产区,尤其是西藏阿里地区藏山羊的产绒量和绒的品质明显优于其他产区,四川茂县藏山羊的产绒量和绒的品质较差;同时,西藏两产区藏山羊的产绒量从年龄上看以4岁较高,从毛色上看以白色个体较高;四个不同生态区内藏山羊的产绒性能差异较大,越严酷的高寒生态条件,其产绒量越高,绒的品质越好。今后应根据不同的生态区按不同的生产方向对藏山羊这一宝贵的基因库资源进行开发利用。 相似文献
1000.
西瓜野生种质耐冷性基因连锁的RAPD标记 总被引:24,自引:0,他引:24
运用RAPD技术进行了西瓜野生材料PI482322耐冷性基因连锁的分子标记的研究,找到了一个分子连锁标记OPG12/1950与耐冷基因连锁,其遗传距离为6.98cM。 相似文献