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991.
AIM: To detect the effects of NK cells on the etiology of severe pre-eclampsia. METHODS: The peripheral blood and umbilical blood from severe pre-eclamptic patients and normal late pregnant women were collected. NK cells were seperated in percoll and counted by SAP. The proliferating ability of NK cells was measured by MTT and killing power of NK cells was determined by [51Cr] releasing test. The immunohistochemistry method was used to detect the quantity of NK cells and the expression of HLA-G in placenta of them. RESULTS: (1) Compared with that in normal late pregnant women, the counts of the NK cells in peripheral blood, umbilical blood and decidua of severe pre-eclamptic patients were significantly higher (all P<0.05). (2) Compared with that in normal late pregnant women, proliferating and killing ability of NK cells in peripheral blood and umbilical blood of severe pre-eclamptic patients were significantly higher. (3) The expression of HLA-G protein in placenta of severe pre-eclampsia group was lower than that in normal group (P<0.05). CONCLUSION: The quantity of NK cells in severe pre-eclamptic patients is increased with stronger biologic function. They may be related with the pathogenesis of severe pre-eclampsia.  相似文献   
992.
茄科植物内生细菌的分离及拮抗菌的筛选   总被引:4,自引:0,他引:4  
从番茄和辣椒植株中共分离到9株对植物病原真菌具有拈抗作用的内生细菌。其中,来自樱桃番茄的内生细菌株系BS-1和湘研辣椒的内生细菌株系BS-4对辣椒根腐病菌等具有较强的拈抗作用,两者在植株体内均可以定殖。BS-1和BS-4均属于芽孢杆菌。  相似文献   
993.
杨树基因工程研究进展   总被引:1,自引:0,他引:1  
杨品前 《江西植保》2005,28(1):21-25
杨树(Populus)是世界上广泛栽培的重要造林树种之一,具有广泛的用途。近年来,杨树基因工程研究进展迅速,本文就近年来国内外学者对杨树基因工程研究成果进行了综述。  相似文献   
994.
应用CPV林间进行越冬代马尾松毛虫防治试验,结果表明不同剂量CPV与1/100000的20%氰戊菊酯乳油复配能显著提高CPV的林间杀虫效果。林间以CPV2.4×106~1.5×105多角体/ml与1/100000的20%氰戊菊酯乳油复配防治越冬代马尾松毛虫为宜,13天幼虫死亡率可达85%以上。  相似文献   
995.
AIM: To investigate the effect of recombinant human interleukin-10 (rhIL-10) on IL-6 and TNF-α levels in serum and liver of mice exposed to lipopolysaccharide (LPS). METHODS: rhIL-10 was prepared by using genetic engineering technology. Mice were intraperitoneally with 500 μg of LPS, and then were treated intravenously with various dosages of rhIL-10. The levels of IL-6 and TNF-α in hepatic tissue and serum were determined by ELISA at 12 h, 24 h, 48 h and 72 h post rhIL-10 treatment. RESULTS: rhIL-10 markedly inhibited the increase in IL-6 and TNF-α levels in hepatic tissue and serum at 12 h after rhIL-10 treatment in LPS-challenged mice, and the inhibition effect was significant at 24-48 h after rhIL-10 treatment (P<0.05). CONCLUSION: rhIL-10 can inhibit the increase in IL-6 and TNF-α levels induced by LPS in mice.  相似文献   
996.
AIM: To down-regulate expression of c-myc through antisense therapy and to investigate its effect on the sensitivity of osteosarcoma MG-63 cells to cisplatin-induced apoptosis. METHODS: The recombinant adenovirus (Ad-Asc-myc) encoding antisense c-myc fragment was constructed and transfected into osteosarcoma MG-63 cells in vitro in order to down-regulate the expression of c-myc, and the change in the sensitivity to cisplatin-induced apoptosis was observed. MTT, Western blot, RT-PCR, flow cytometry (FCM) and electron microscope were used to evaluate tumor cell proliferation in vitro, genes expression related to apoptosis regulation and effects on the sensitivity of osteosarcoma MG-63 cells to cisplatin-induced apoptosis. RESULTS: Ad-Asc-myc down-regulated the expression of c-myc protein after transfected MG-63 cells for 48 h, combined with the treatment of 2.0 mg/L cisplatin for 2 h inhibited tumor cell proliferation in vitro by 38.0%. RT-PCR revealed that Ad-Asc-myc down-regulated the expression of Bcl-2 and up-regulated the expression of Bax. No appreciable change was observed in the expression of E2F-1. FCM showed that Ad-Asc-myc induced apoptosis in intransfected cells, and rendered it more sensitive to cisplatin. CONCLUSION: Antisense c-myc is able per se to induce apoptosis and sensitize osteosarcoma cells to cisplatin-induced apoptosis.  相似文献   
997.
AIM: To investigate the association of gene polymorphism at position 196 of tumor necrosis factor receptor Ⅱ (TNFRⅡ) with systemic lupus erythematosus (SLE) in Chinese, and establish recombinant retroviral vector to analyze the function of the TNFRⅡ 196M/R. METHODS: The genotype at position 196 of TNFRⅡ was determined by PCR-RFLP in 106 SLE patients and 119 healthy controls in china. Human TNFRⅡ196M cDNA were amplified by PCR and cloned into PMD18-T vector. Then, PMD18-TNFRⅡ196R was induced by site-directed mutagenesis. The recombinant T vector, PMD18-TNFRⅡ196M and PMD18-TNFRⅡ196R, were subcloned into retroviral vector PLXSN. Both normal and variant were transfected into rat mesangial cell. The effects of TNFα on production of sTNFRⅡ and IL-6 were study by ELISA. RESULTS: (1) The frequency of TNFRⅡ196R allele was significantly higher than those in controls (35.2% vs 14.3%, P<0.05); (2) The recombinant retroviral vector (PLXSN-TNFR 196M and PLXSN-TNFR 196R) was constructed successfully; (3) rhTNFα caused a significant increase in IL-6 production by rat mesangial cells transfected with PLXSN-TNFRⅡ196R than that with TNFRⅡ196M. CONCLUSION: These data indicate that TNFRⅡ196R allele is associated with SLE in the Chinese. TNFRⅡ196R transduces the signals of TNFα more effectively than TNFRⅡ196M, which may be involved in the pathogenesis of SLE.  相似文献   
998.
AIM: In this study, we investigated the anticancer effect and mechanisms of manumycin on pancreatic cancer cell line-Panc-1 and the role of p38MAPK pathway in apoptosis. METHODS: The test of anticancer effect was performed by MTT assay. Apoptosis was induced in the cells by manumycin and then treated with SB203580, a specific p38MAPK inhibitor. A quantitative caspase-3 activity assay kit was used in this experiment. RESULTS: Manumycin (6 μmol/L, 18 μmol/L, 54 μmol/L) significantly inhibited cell growth of pancreatic cancer cell line Panc-1. The inhibition rates 24 h after treatment with 6 μmol/L, 18 μmol/L and 54 μmol/L manumycin were 8.9%, 21.9% and 67.0%, respectively. Compared with the control group, the survival levels of the last two groups were of significant statistical difference (P<0.01). The anticancer effects also showed dosage-effect relationship, the value of IC50 24 h after treatment was 34.7 μmol/L. In addition, this reagent simultaneously activated caspase-3 protein, which was partly blocked by p38MAPK specific inhibitor, SB203580. CONCLUSION: Manumycin exerted anticancer effect on Panc-1 cell line via inducing cell apoptosis, which was partly regulated by p38MAPK.  相似文献   
999.
包膜控释尿素对大棚番茄的增产与品质提高效应   总被引:4,自引:0,他引:4  
对施用包膜控释尿素和普通尿素的大棚番茄进行了田间生产条件下产量与品质对比分析试验。结果表明:与普通尿素相比施用控释尿素有显著的增产效果。D 60控释处理(控释期60 d)产量最高,为68.85 t/hm2,比对照增产19.39 t/hm2,增产率为39.2%;比尿素增产10.10 t/hm2,增产率为17.2%;D 90(控释期90 d)比对照增产15.37 t/hm2,增产率为31.0%;比尿素增产6.08 t/hm2。增产率为10.3%;D 90与D 60两种控释尿素之间产量差异不显著。控释尿素具有增加单株果数、单果重的效果。D 90与D 60氮素当季利用率比普通尿素分别高65.5%和108.8%。硝酸盐含量,以D 90为最低,仅比对照高4.4%,比普通尿素低56%;D 60比对照高15%,比尿素处理低51.6%;尿素处理比对照高137.3%。V c和氨基酸含量,D 90为最高,分别比对照高1.00倍和2.46倍;比普通尿素处理高22%和100%;D 60与尿素两处理V c含量差异不显著,但氨基酸总量前者却比后者高48%。可溶性糖含量以D 60较高,普通尿素为最低。综合品质指标为:D 90>D 60>U。说明控释尿素具有显著地增产效应和提高蔬菜品质的突出效应,特别在提高蔬菜的安全品质方面贡献最大。综合各项,在番茄生产中以选用控释期为60 d的包膜控释尿素为最好。  相似文献   
1000.
以新陆早7号为试材,进行了不同水肥条件下膜下滴灌棉株群体冠层结构测定和产量结果分析。试验表明,合理水肥条件下的棉株群体叶面积指数(LAI)、叶倾角(MLA)和散射光透过率(TD),在盛花盛铃期分别为3.55~3.95、40°~48°和18.5%~28.1%。在一定水肥范围内,滴灌棉花产量随灌水量和施肥量的增加而增加,但超过一定阈值产量有下降趋势。适宜水肥条件下产量最高。  相似文献   
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