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AIM:To investigate the effects of phytoestrogen α-zearalanol (ZAL) on hypoxia/reoxygenation (H/R) injury and mechanism involved in human umbilical vein endothelial cells (HUVECs). METHODS:HUVECs were exposed to hypoxia for 3 hours and then reoxygenation 1 hour. ZAL or 17β-estradiol (E2) at concentrations of 10-9-10-6 mol/L were pretreated before hypoxia. The survival rate of HUVECs was detected by MTT. Either the activities of LDH and SOD or the level of MDA in supernatant was detected by spectrophotometry. RESULTS:The survival rate of HUVECs and the activity of SOD were significantly decreased (P<0.01), while the activity of LDH and the level of MDA were significantly increased (P<0.01) after H/R. These changes were reversed by pretreatment with ZAL or E2, and there was no significant difference between their effects in the same dose of ZAL and E2. CONCLUSION:These results suggest that phytoestrogen ZAL protects HUVECs from H/R injury by inhibiting the oxidative stress, which was similar to E2. 相似文献
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AIM:To determine the migration mode of host lymphocytes into the intestinal graft by analyzing different lymphoid compartments of the graft. METHODS:2, 4, 6 days after transplantation, murine intestinal grafts were harvested for histologic assessment. Lymphocytes were collected from mesenteric lymph nodes (MLN), Peyer’s patch (PP), lamina propria lymphocytes (LPL) and intraepithelial lymphocytes (IEL) in the graft for analyzing by cytometry. RESULTS:At the day 2 and day 4, no evidence of rejection in intestinal allograft was found, while the rejection signs were apparent at the 6th day. At day 2 and day 4, host lymphocytes had rapidly replaced donor cell in graft MLN and PP. The migration of host lymphocytes into the LPL and IEL was not as fast as MLN and PP, however, the near-total replacement took place at the 6th post transplant day. The host lymphocytes were activated at the early stage of recruitment into the graft. CONCLUSION:The rapid recruitment of recipient lymphocytes and early activation could be responsible for the formidable rejection of intestinal transplantation. 相似文献
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QIU Hai-xia GU Ying LIU Fan-guang ZENG Yao-ying HUANG Xiu-yan ZHAO Jing-xian ZENG Jing 《园艺学报》2006,22(2):234-238
AIM: To investigate the characterization of absorption of hematoporphyrin monomerthyl ether (HMME), a domestic new generation photosensitizer product, by activated T cells from human peripheral blood. METHODS: Evaluation was performed by flow cytometry on the effects of incubating concentration and time of HMME on absorption by activated T cells. Lymphocytes were separated from human peripheral blood by density gradient centrifugation with Ficoll and T cells were activated with polyclonal stimulators PHA and PDB+Ion. To analyze the effects of HMME incubating doses on the absorption of activated T cells, the cultural lymphocytes were incubated with a serial doses of HMME for 1 h and HMME absorption were measured by FACS after immuno-staining with anti-CD3 antibody. To test the impact of HMME incubating time on the absorption of activated T cells, the cultural lymphocytes were incubated with HMME for various times and HMME absorption were measured by FACS after immuno-staining with anti-CD3 antibody. RESULTS: The HMME absorption-dose curve and absorption-time curve were shifted to right and up in the activated T cells as compared to resting T cells. HMME absorptions of activated T cells were statistic significantly larger than that of resting T cells in the doses between 5 mg/L to 20 mg/L. HMME absorptions of either activated T cells or resting T cells underwent a gradual increase with the incubation-time in HMME at concentration of 10 mg/L. HMME absorptions of activated T cells were statistic significantly larger than that of resting T cells in the incubation-time between 15 to 60 min. CONCLUSION: The differences of HMME absorption between activated T cells and resting T cells depend on the incubation times and doses of HMME. HMME absorption of activated T cells are significantly larger than that of resting T cells in certain incubation-times and doses. These results suggest that incubation time and dose associated with HMME-PDT therapeutic windows will be created for selective deletion of activated T cells. 相似文献
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基于GIS的中国苜蓿资源分布和生产力分析 总被引:1,自引:0,他引:1
针对目前我国苜蓿种植缺乏合理的规划和布局、盲目引种等问题,于2006年初对全国苜蓿种植县开展了的问卷调查,对目前苜蓿资源情况进行了全面了解,并利用地理信息系统(GIS)对其空间分布和生产力状况进行了详细分析。研究表明,截止到2005年全国16个省区的614个苜蓿分布旗县的苜蓿累计保留面积达254.77万hm2,占全国人工草地面积的50.8%;并按照面积数据分布情况将其划分为5级(小于333hm^2、333~3333hm^2、3333~10000hm^2、10000~33333hm^2、33333~74313hm^2),各级分别占苜蓿总面积的0.83%、14.49%、28.84%、42.45%、13.62%;苜蓿平均干草单产为10150kg/hm^2,占总面积的46%;根据数据分布情况将干草产量数据划分为5级(小于3000kg/hm^2、3000~7500kg/hm^2、7500~12000kg/hm^2、12000~18000kg/hm^2、18000~31005kg/hm^2),各级分别占总面积的14.32%、21.31%、46.75%、14.86%、0.83%;全国苜蓿种子田面积17.29万hm^2,种子平均单产为325.13kg/hm^2。 相似文献
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将人溶菌酶(human lysozyme,hLYZ)cDNA插入由pcDNA3改造而成的pcDNAK表达载体。用获得的重组载体pcDNAKLYZ转染COS-1细胞,经免疫荧光试验证明能进行正确表达。将重组载体注射于哺乳母鼠,取其乳汁进行溶菌酶活性测定,结果显示,分泌在乳汁中的重组hLYZ高达139mg/L。根据乳汁体细胞检测结果,选择健康奶牛和乳腺炎阳性奶牛,分别在干奶时和产犊前2周2次注射重组质粒pcDNAKLYZ,注射途径为乳腺基部穿刺,注射剂量为300μg/乳区,于产犊后1个月采集奶样进行体细胞检测,结果显示,对前一泌乳期发生的奶牛乳腺炎的治愈率为91.5%,对下一泌乳期奶牛孔腺炎的预防有效率王少为96.97%。由此认为。构建的表达hLYZ基因的重组表达质粒,可以替代抗菌素类油乳剂用于干乳期乳腺炎的防治。 相似文献