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991.
992.
AIM:To investigate the possible mechanism of deferoxamine on angiogenesis in rat hypoxic-ischemic encephalopathy (HIE). METHODS:SD rats (7 days of age) were used to make HIE model. Model group and treatment group were injected with deferoxamine or normal saline alone 24 hours before hypoxic-ischemic insult. Rats were sacrificed at 1,3,7 or 14 days after hypoxic-ischemic insult. Brain capillary density index (BCDI),the number of proliferating capillary,brain water content and extent of brain atrophy were determined. The expression of vascular endothelial growth factor (VEGF) and hypoxia-inducible factor-1α(HIF-1α) mRNA was measured. RESULTS:Early water content and late atrophic ratio of the left brain were significantly improved in the treatment group compared to model group (P<0.01). The number of proliferating capillary in the treatment group was significantly higher than that in the model group [(2.01±0.31)/HPF vs (0.90±0.25)/HPF,P<0.01]. Deferoxamine markedly up-regulated the expression of VEGF and HIF-1α mRNA in the brain [VEGF at 12 h: (1.41±0.07) vs (1.10±.15),P<0.05; HIF-1α at 12 h: (1.49±0.12) vs (1.11±0.16),P<0.05].CONCLUSION:Deferoxamine may promote angiogenesis and attenuate hypoxic-ischemic induced brain injury via up-regulation of HIF-1α and VEGF expression. 相似文献
993.
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
994.
995.
以Navier-Stokes方程为模型基础,运用ANSYS/FLOTRAN软件对华北型机械通风式连栋塑料温室在不同山墙门打开度情况下室内的气流场进行三维稳态模拟.同时通过试验测得温室内各测点的气流流速,并分析试验数据得到温室内的气流流速的平均值.结果表明:在试验条件下山墙门打开度为2.3×2 m2,造成室内局部风速过大,流场分布紊乱;山墙门打开度为2.3×3m2,使室内风速平均值太小,达不到温室通风的要求;山墙门打开度为2.3×2.4m2时在同等条件下温室内的气流场分布均匀,平均风速最大,通风效果较理想. 相似文献
996.
997.
AIM: The aim of this study was to examine the microstatellite instability (MSI) and loss of heterozygosity(LOH) of locus D17S396 on chromosome 17 and their influence on the expression of nm23H1 in hepatocellular carcinoma (HCC),which may provide experimental evidence for the mechanism of nm23H1 gene and tumor metastasis.METHODS: Techniques such as DNA extraction from formalin-fixed paraffin-embedded tissues,PCR-SSCP,ordinary silver stain were used to study MSI and LOH of locus D17S396.Envision immunohistochemistry and Leica-Qwin computer imaging techniques were used to assess the expression of nm23H1.RESULTS: ① The frequency of heredity instability of HCCs was 35.42%.The frequency of LOH in the cases with lymph node or distant organs metastasis or not and with intrahepatic metastasis or embolus of portal vein or not was significantly different (P<0.01),it was higher in stage TNM Ⅲ than that in stageⅠ and Ⅱ.Moreover,it was higher in high tendency to invasion or metastasis cases than that in the low tendency cases (P<0.01).② The expression of nm23H1 was 56.25%.It was significantly different in Edmondson grade,TNM stage and in lymph node or distant organ metastasis cases (P<0.01).The cases with high tendency of invasion or metastasis exhibited lower nm23H1 expression compared with low tendency cases (P<0.01).③ The positive rate of nm23H1 protein in LOH positive group was lower than that in LOH negative group (P<0.05).CONCLUSION: The results indicate that both MSI and LOH of nm23H1 gene control the development of HCC independently in different pathways.LOH inhibits the expression of nm23H1,which endows it with high aggressive and poor prognosis.Increase in the amount of nm23H1 protein expression effectively restrains the tendency to invasion or metastasis of HCCs and improves prognosis of patients. 相似文献
998.
不同钠盐胁迫对高冰草种子萌发的影响 总被引:12,自引:0,他引:12
通过对高冰草种子在不同钠盐(NaCl、NaHCO3、Na2CO3)溶液中萌发情况的研究,旨在探明高冰草种子在不同盐胁迫下的萌发特性。结果表明:碱性盐(NaHCO3、Na2CO3)胁迫较中性盐(NaCl)胁迫显著降低了高冰草的发芽率。高冰草种子在NaCl浓度150mmol/L、NaHCO3浓度100mmol/L和Na2CO3浓度50mmol/L时萌发受到明显抑制。不同钠盐胁迫下高冰草种子胚根和胚芽的受抑制大小顺序为,中性盐NaCl胁迫:胚根<胚芽;碱性盐NaHCO3和Na2CO3胁迫:胚根>胚芽。 相似文献
999.
蚜虫是为害十字花科蔬菜的主要害虫之一,该虫主要以成虫和若虫群集在蔬菜叶片上吸食汁液,危害后造成叶片卷曲变形,植株生长不良,还排出大量的蜜露、蜕皮而污染叶面,降低蔬菜商品价值.此外,蚜虫还传播多种病毒病.而随着农药的使用量的逐年加大,蚜虫的抗药性逐年增强,常用农药防治效果下降.为了了解啶虫脒对十字花科蔬菜蚜虫的防治效果,找寻高效、低毒、安全的替代农药,特进行本试验. 相似文献
1000.
本文用提纯的IBDV细胞毒为抗原,抗鸡Ig单抗1B7HRP酶结合物为第二抗体建立了检测IBDV抗体的间接ELISA。在此基础上研制出IBDV抗体检测诊断试剂盒。经对1200份血清进行检测,结果表明:本试剂盒特异性强,灵敏度高,重复性好,快速稳定,易于操作,为雏鸡IBDV母原抗体和疫苗注射后特异性抗体检测提供了可靠的诊断工具。 相似文献