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排序方式: 共有576条查询结果,搜索用时 15 毫秒
1.
AIM:To study the effect of TGF-β1 and TNF-α antisense PS-ODNS on ex vivo expansion of hematopoietic stem/progenitor cells (HSPC). METHODS:CD34+cells were purified from fresh umbilical cord blood by immunomagnetic beads, and mononuclear cells were purified from bone marrow by Ficoll-hypaque. The effects of TGF-β1 and /or TNF-α antisense PS-ODNS on ex vivo expansion of CD34+ cells、CFU-GEMM、CFU-GM、CFU-E and BFU-E were detected by using liquid and semi-solid culture systems.RESULTS:TGF-β1 antisense PS-ODNS cooperated with cytokines increased the number of CD34+ cells, CFU-GEMM, CFU-GM, CFU-E and BFU-E, which was as 4, 2.6, 2.7, 1.8, 2.1 times as that of the control (the cytokines combination), respectively. TNF-α antisense PS-ODNS cooperated with cytokines respectively increased the number of CD34+ cells, CFU-GEMM, CFU-GM, CFU-E and BFU-E by 4, 2.9, 2.6, 1.7, 1.8 times as that of the control. The above two antisense PS-ODNS cooperated with cytokines could respectively increased the number of CD34+ cells, CFU-GEMM, CFU-GM, CFU-E and BFU-E by 5.3, 2.1, 2.7, 1.9, 1.8 times as that of the control.CONCLUSION:Inhibition of endogenous TGF-β1 and TNF-α by antisense PS-ODNS will be one of the effective methods to expand HSPC ex vivo. 相似文献
2.
ZHENG Jia-ying LI Ya-dong ZHENG Qing-zhu YU Li-li WU Qing-wei QIU Fu-nan WU Yan-an HUANG Yi 《园艺学报》2019,35(5):804-812
AIM: To study the expression of zinc transporter ZRT/IRT-like protein 14 (ZIP14) in the hepatocellular carcinoma (HCC) tissues, and to investigate the effects of ZIP14 over-expression on the biological behaviors of HCC cells. METHODS: The expression of ZIP14 at mRNA and protein levels in the HCC tissues and adjacent non-tumor tissues were detected by real-time PCR and immunohistochemical staining, respectively. The lentivirus expression system containing GV365-ZIP14 was constructed, and was used to infect the HCC cell line BEL-7404, which had relatively poor expression of ZIP14. The expression of ZIP14 at mRNA and protein levels in the transfected cells were detected by real-time PCR and Western blot, respectively. Under the conditions of zinc sulfate stimulation at different concentrations, the cell viability, the cell cycle, and the cell migration and invasion abilities were detected by MTT assay, DNA ploid detection, and Transwell assay, respectively. RESULTS: The mRNA expression level and the strong-positive rate of protein expression of ZIP14 in the HCC tissues were significantly lower than those in the adjacent non-tumor liver tissues (P<0.01). The expression of ZIP14 at mRNA and protein levels in the BEL7404 cells was significantly enhanced by infection of GV365-ZIP14 expression lentivirus. Compared with negative control group (transfected with negative control lentivirus), the cell viability, migration and invasion in ZIP14 over-expression group (transfected with GV365-ZIP14 expression lentivirus) were significantly reduced, and the percentage of the cells in G2/M phase was significantly increased, all of which were more obvious with the elevation of zinc concentration in the culture medium. CONCLUSION: ZIP14 is low expressed in the HCC tissues. The ZIP14 over-expression has inhibitory effects on the viability, migration and invasion of HCC cells, and blocks the cell cycle in G2/M phase, which might be closely related to the elevation of zinc concentration in cytoplasma of HCC cells due to enchanced zinc transport by ZIP14. 相似文献
3.
试验旨在鉴定吉林省某雏鸡孵育基地病死雏鸡组织中分离出的1株致病性菌CCGGD201101株并测定其致病性。对疑似致病菌进行生理生化试验、16S rDNA测序鉴定,并人工接种昆明鼠,测定其半数致死量,验证细菌毒力。经鉴定该菌为鲍曼不动杆菌(Acinetobacter baumannii)。以鲍曼不动杆菌CCGGD201101分离株为研究对象,并以鲍曼不动杆菌标准株(ATCC 19606)为对照,测得半数致死量,进一步证明鲍曼不动杆菌病死鸡分离株CCGGD201101具有较强致病性。 相似文献
4.
LI Qin CHEN Yu-cun ZHAO Feng-yong ZHANG Jia-min ZHANG Shu-hui ZHU Zi-yan 《中国畜牧兽医》2016,43(7):1850-1855
In this study,we aimed to determine whether bear had different blood group systems.Whole blood samples were collected from 40 Asiatic Black bears in Fujian province,China.Tube method was used to detect antibodies in plasma,and antibody isotype was determined with 2-mercaptoethanol.Plasma was further analyzed by mass spectrometry.The plasma from four bears had antibodies,possibly IgM isoform,which could agglutinate RBCs from 30 bears.Blood samples from 10 bears were tested by human blood typing reagents.The results showed that 4 bears had blood type like human type O,while 6 bears had like human type B.Plasma protein had extensive homology to serum albumin-like isoform 1 found in giant panda (Ailuropodamelanoleuca).We suggested that Asiatic Black bear might have at least one blood group system with two blood types.If the sick bear needs blood transfusion,a cross-matching test was necessary.Moreover,giant panda might receive blood from Asiatic Black bear in case of emergency. 相似文献
5.
分析了家具方案设计的创新性、不确定性、层次性、多样性、经验性和反复性等基本特征,并阐述了家具方案设计的过程与内容,界定了家具方案设计评价的概念,模糊评价法、提出层次分析法、价值工程法、灰色系统评价法、感性评价法和人工神经网络评价法等家具设计方案评价方法。 相似文献
6.
AIM: To explore the possible mechanism of tert-butyl hydroperoxide (t-BHP)-induced apoptosis in rat cortical neurons. METHODS: Primary cultured rat cortical neurons were performed in vitro and cell viability was measured by MTT assay. DNA fragmentation was used to evaluate cell apoptosis and mitochondrial transmembrane potential (ΔΨm) was determined by flow cytometric assay. Cellular glutathione (GSH) content was measured by spectrophotometer. Bcl-2 and Bax protein, cytosolic cytochrome c, cleaved caspase-3 and poly (ADP-ribose) polymerase (PARP) were detected by Western blotting. RESULTS: After exposure of cortical neurons to tBHP (25-400 μmol/L), the cell viability was reduced. ΔΨm and cellular GSH content were also decreased significantly. The level of Bcl-2 protein was reduced and Bax was elevated. Meanwhile, tBHP exposure resulted in cytochrome c release, caspase-3 and PARP proteolysis, DNA fragmentation and eventually neuron apoptosis. CONCLUSION: Mitochondrial damage may mediate tBHP- induced apoptosis in cortical neurons. 相似文献
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9.
AIM: To explore the changes of excitatory amino acids and N-methyl-D-aspartate receptor (NMDAR) in brain undergoing ischemia-reperfusion injury following hepatic portal occlusion (HPO) in vivo.METHODS: The electrolytes and pH of portal vein blood,the content of Glu and Asp in brain,and the expression of NMDAR mRNA were studied with blood-gas analysis,HPLC and semi-quantitative RT-PCR method in two groups(HPO or sham),respectively.Three time points(6 h,12 h and 24h after reperfusion) were included.RESULTS: HPLC measure showed that the content of cortex Glu and Asp in group HPO elevated significantly after reperfusion compared with sham group, the peaks were at 6 h and 24 h [Glu:(349±145) μg·g-1wt,(456±203) μg·g-1wt vs (238±24) μg·g-1wt,(225±59) μg·g-1wt;Asp:(134±50) μg·g-1wt,(166±50) μg·g-1wt vs (99±24) μg·g-1wt,(71±20) μg·g-1wt].Moreover,semi-quantitative RT-PCR analysis discovered that the expression of NMDAR mRNA increased significantly ,the subunit NR1 mRNA was higher in reperfusion 6 h and last to 12 h(1.63±0.06 vs 1.18±0.05;1.73±0.06 vs 1.17±0.03),the peak of NR2B mRNA was in 12 h (1.75±0.04 vs 1.18±0.05) ,but they did not further increase after reperfusion for 24 h.CONCLUSION: HPO increases the content of Glu and Asp and the expression of NMDAR in brain cortex.The Glu-NMDAR pathway plays a role in the mechanism for the brain injury after HPO.The products of IR injury might be the key factor to cause EAAs acumulation in synapse space. 相似文献
10.
宋丽钦 《农业图书情报学刊》2010,22(6):123-124,135
阐述了古籍特藏库房环境因素对古籍保存的影响,及有害生物发生的条件,探讨抑制或阻止有害生物危害古籍最有效的措施。并就如何应用现代技术发展保护传统技术,更好的传承古籍保护工作提出个人看法。 相似文献