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991.
992.
目的:比较3种不同人精子冷存液的冷冻效果。方法:采用传统的精子冷存液(TYB)及实验室自制的两种无盐冷存液Sirm 1和Sirm 2冷存人精子。冷冻前及解冻后应用CASA分析精子的相关运动参数。结果:TYB冷存的精子数量、能动力及进一步活动度均高于另两种无盐冷存液(P〈0.01),而Sirm 1和Sirm 2之间的冷冻效果无任何差异。结论:用TYB冷冻液冷存精子可以得到较好的冷冻效果。 相似文献
993.
三维多孔β-磷酸三钙支架与骨髓基质细胞构建组织工程骨的生物相容性及显微形态学观察 总被引:1,自引:2,他引:1
目的:定量及显微观察三维多孔β-磷酸三钙支架在构建组织工程骨时的组织相容性。方法:实验于2002-07/2005-07在第四军医大学口腔医学院颌面外科组织工程实验室完成。将兔的骨髓基质细胞,按一定量分置在培养板的各孔内,将多孔β-磷酸三钙支架材料置入孔内共培养,采用MTT法和碱性磷酸酶试剂盒检测骨髓基质细胞活性,共聚焦显微镜观察其在β-磷酸三钙支架表面的微观形态。结果:①倒置显微镜下观察接种前的细胞形态基本均匀一致。②接种后6d扫描电镜观察显示,材料表面可见较多细胞和细胞合成的丝状细胞外基质。③细胞接种后6d激光共聚焦显微镜观察显示,细胞数量明显增多,基本长满材料的表面,同时在孔隙中,也有大量细胞长入。④β-磷酸三钙对骨髓基质细胞的增殖作用:培养第5天,β-磷酸三钙组对骨髓基质细胞的增殖作用(A)低于对照组,差异有显著性意义(分别为0.47±0.02,0.52±0.02,t=2.281,P<0.05)。⑤β-磷酸三钙对骨髓基质细胞的碱性磷酸酶的活性比较:在骨髓基质细胞诱导培养5,7,9d,β-磷酸三钙组碱性磷酸酶的活性(A)明显低于对照组,差异有显著性意义(分别为5.18±0.31,6.05±0.54;12.35±0.62,14.17±0.70;15.68±0.87,17.13±1.14,t=3.302,6.025,6.019,P<0.05)。结论:三维多孔β-磷酸三钙支架有良好的组织相容性,为其应用于临床提供了可靠的实验依据。 相似文献
994.
目的:将许旺细胞与细胞外基质凝胶、聚乳酸-羟基乙酸共聚物纤维丝复合培养,观察许旺细胞的存活、黏附、三维生长和迁移等生物学行为。方法:实验于2005-02/2006-03在四川大学完成。①实验材料:3~6月龄SD大鼠40只。16~24周流产胎儿由四川大学华西二医院计划生育科提供,产妇及其家属均签署知情同意书,实验经医学伦理委员会批准。聚乳酸-羟基乙酸共聚物(中国科学院成都分院化学所提供);细胞外基质凝胶(Sigma)。②实验方法:将聚乳酸-羟基乙酸共聚物溶解,旋转抽丝法制成直径为20~40μm的聚乳酸-羟基乙酸共聚物纤维丝。无菌条件下取胎儿坐骨神经,去除神经外膜,胰酶消化 差速贴壁法去除成纤维细胞,达80%融合时行BrdU标记。③实验评估:将许旺细胞离心制成0.1~0.2mm3的微粒,接种在细胞外基质凝胶中,观察许旺细胞在凝胶中的存活、生长和移行。将许旺细胞制成1×1010L-1的30%细胞外基质凝胶后,分别滴加在经过胶原、细胞外基质凝胶预处理的聚乳酸-羟基乙酸共聚物纤维丝的一端,观察许旺细胞在纤维丝上的黏附、生长和迁移。将BrdU标记的许旺细胞复合细胞外基质凝胶后,置入聚乳酸纤维管用以修复大鼠坐骨神经缺损,术后3,6周取材,BrdU免疫组化染色观察许旺细胞的存活情况。结果:①许旺细胞在无血清状态下能在细胞外基质凝胶中存活,并分裂、增殖,相互移行形成类似Bungner带状的许旺细胞柱状结构。②许旺细胞能贴附在聚乳酸-羟基乙酸共聚物纤维丝上生长并沿纤维丝移行,形成多层排列的类似Bungner带状的许旺细胞柱,细胞外基质凝胶能显著增加贴附和移行细胞数量,而胶原作用不显著。③许旺细胞和细胞外基质凝胶复合移植,6周后BrdU阳性细胞数明显低于第3周(t=3.71,P<0.01),成活细胞能在细胞外基质凝胶中移行。结论:许旺细胞与细胞外基质凝胶、聚乳酸-羟基乙酸共聚物纤维丝等生物材料复合培养时,能存活、分裂、增殖,相互移行形成类似Bungner带状的细胞柱,并可贴附在纤维丝上生长迁移,该生物学行为对神经组织工程具有重要作用。 相似文献
995.
JF Winther JD Boice Jr K Frederiksen A Bautz JJ Mulvihill M Stovall JH Olsen 《Clinical genetics》2009,75(1):50-56
Offspring of childhood cancer survivors may be at risk of genetic disease due to the mutagenic cancer treatments received by their parents. Congenital malformations were evaluated in a population-based cohort study of 1715 offspring of 3963 childhood cancer survivors and 6009 offspring of 5657 survivors' siblings. The Danish Central Population Register, Cancer Registry and Hospital Register were used to identify study subjects and congenital malformations. Gonadal and uterine radiation doses were characterized based on standard radiation-treatment regimens. The prevalence of congenital malformations at birth in offspring of survivors (44 cases, 2.6%) was slightly higher but not statistically different from that of offspring of siblings (140 cases, 2.3%) [prevalence proportion ratio (PPR), 1.1; 95% confidence interval, 0.8–1.5] or of the general population (observed-to-expected ratio, 1.2; 0.9–1.6). Including malformations diagnosed later in life did not change the ratios appreciably. The risk for malformations was slightly higher in the offspring of irradiated parents than in that of non-irradiated parents (PPR 1.2 vs 1.0) but was unrelated to gonadal dose. This study provides evidence that cancer therapy of children does not increase the risk for malformations in their offspring. Continued monitoring of genetic risks among their offspring, however, is warranted. 相似文献
996.
997.
建立大鼠骨髓源性树突状细胞体外扩增及纯化的方法 总被引:1,自引:1,他引:0
目的:目前对树突状细胞的研究主要集中在人及小鼠系统,关于大鼠树突状细胞特性和功能的研究较少。体外扩增并纯化大鼠骨髓树突状细胞的方法,并对其进行形态学和免疫学鉴定。方法:实验于2004-06/2005-06在第四军医大学西京医院耳鼻喉科实验室完成。实验材料:8~12周龄雌性SD大鼠由第四军医大学实验动物中心提供,实验过程中对动物处置符合动物伦理学标准。实验方法:①参考Oliver方法,利用黏附法诱导分离SD大鼠骨髓细胞,获得高纯度的树突状细胞。采用扫描电镜和透射电镜观察培养6,8,10,12 d与12 d加内毒素情况下细胞形态,并采用流式细胞仪鉴定。②无菌条件下取出大鼠脾脏加RPMI1640培养液研磨并通过不锈钢筛网,收集未贴壁细胞,以RPMI1640培养液冲洗出的细胞作为反应细胞。取96孔培养板加入反应细胞,并按照1∶480,1∶240,1∶120,1∶60比例加入刺激细胞。采用ELX800型酶联免疫检测仪测定波长为490 nm处吸光度值。结果:①随培养时间的增长,细胞逐渐成熟,培养12 d的细胞形态不规则,表面有大量树突状突起,培养12 d加内毒素的细胞进一步成熟,体积增大,高表达CD80、CD86分子。②随着培养时间和树突状细胞数目的增加,树突状细胞刺激T细胞增殖的能力逐渐增强,加入内毒素后这种能力进一步加强。结论:成功地建立了体外大量扩增大鼠骨髓树突状细胞方法,并可在培养过程中收获不同成熟状态树突状细胞。 相似文献
998.
JS Lagas CM van der Kruijssen K van de Wetering JH Beijnen AH Schinkel 《Drug metabolism and disposition》2009,37(1):129-136
Diclofenac is an important analgesic and anti-inflammatory drug, widely used for treatment of postoperative pain, rheumatoid arthritis, and chronic pain associated with cancer. Consequently, diclofenac is often used in combination regimens and undesirable drug-drug interactions may occur. Because many drug-drug interactions may occur at the level of drug transporting proteins, we studied interactions of diclofenac with apical ATP-binding cassette (ABC) multidrug efflux transporters. Using Madin-Darby canine kidney (MDCK)-II cells transfected with human P-glycoprotein (P-gp; MDR1/ABCB1), multidrug resistance protein 2 (MRP2/ABCC2), and breast cancer resistance protein (BCRP/ABCG2) and murine Bcrp1, we found that diclofenac was efficiently transported by murine Bcrp1 and moderately by human BCRP but not by P-gp or MRP2. Furthermore, in Sf9-BCRP membrane vesicles diclofenac inhibited transport of methotrexate in a concentration-dependent manner. We next used MDCK-II-MRP2 cells to study interactions of diclofenac with MRP2-mediated drug transport. Diclofenac stimulated paclitaxel, docetaxel, and saquinavir transport at only 50 microM. We further found that the uricosuric drug benzbromarone stimulated MRP2 at an even lower concentration, having maximal stimulatory activity at only 2 microM. Diclofenac and benzbromarone stimulated MRP2-mediated transport of amphipathic lipophilic drugs at 10- and 250-fold lower concentrations, respectively, than reported for other MRP2 stimulators. Because these concentrations are readily achieved in patients, adverse drug-drug interactions may occur, for example, during cancer therapy, in which drug concentrations are often critical and stimulation of elimination via MRP2 may result in suboptimal chemotherapeutic drug concentrations. Moreover, stimulation of MRP2 activity in tumors may lead to increased efflux of chemotherapeutic drugs and thereby drug resistance. 相似文献
999.
Blum K Chen AL Chen TJ Prihoda TJ Schoolfield J DiNubile N Waite RL Arcuri V Kerner M Braverman ER Rhoades P Tung H 《Advances in therapy》2008,25(7):644-657
INTRODUCTION: This meta-analysis was conducted to systematically review the efficacy and safety of the H-Wave(R) (Electronic Waveform Lab, Inc, Huntington Beach, CA, USA) device and programme as a non-pharmacological analgesic treatment in chronic soft tissue inflammation and neuropathic pain. METHODS: Five studies related to pain relief, reduction in pain medication and increased functionality obtained with the H-Wave device were included in the analysis. Data were analysed using the random effects model, including adjustment to evaluate variability, size of study and bias in effect size. A total of 6535 participants were included in the meta-analysis; there were 8065 participants' outcomes measured due to multiple measurements per participant. RESULTS: The H-Wave device decreased pain ratings across various chronic soft tissue inflammation and neuropathic pain conditions. The mean weighted effect size was 0.59, and the estimated effect size variance was 0.00003 (95% confidence intervals [CI]: 0.580, 0.600). The H-Wave device also decreased the intake of pain medication in patients with various chronic soft tissue inflammation and neuropathic pain conditions. The mean weighted effect size was 0.56, and the estimated effect size variance was 0.000013 (95% CI: 0.553, 0.567). Patient functionality was also improved with use of the H-Wave device. The mean weighted effect size was 0.70, and the estimated effect size variance was 0.00002 (95% CI: 0.691, 0.709). A chi-square test for homogeneous effect sizes found highly significant (P<0.00001) variability, indicating a robust significant effect size for increased functionality relative to both pain relief and reduction in pain medication. There was little to no evidence of any adverse effects associated with the use of the H-Wave device. CONCLUSION: The findings indicate a moderate to strong effect of the H-Wave device in providing pain relief, reducing the requirement for pain medication and increasing functionality. The most robust effect was observed for improved functionality, suggesting that the H-Wave device may facilitate a quicker return to work and other related daily activities. 相似文献
1000.
Efficacy of adjuvant chemotherapy according to hormone receptor status in young patients with breast cancer: a pooled analysis 下载免费PDF全文
van der Hage JA Mieog JS van de Vijver MJ van de Velde CJ;European Organization for Research Treatment of Cancer 《Breast cancer research : BCR》2007,9(5):R70