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971.
雷公藤红素对人肥大细胞系粘附能力和粘附分子表达的影响 总被引:4,自引:0,他引:4
雷公藤红素是雷公藤单体之一.本文研究雷公藤红素对人肥大细胞系HMC-1细胞粘附及粘附分子表达的影响.结果发现:HMC-1细胞能自发地表达β1、β3型整合素和CD44,不表达β2型整合素,具有迅速粘附于鼠尾胶的能力,在粘附过程中细胞由圆形、椭圆形变成梭形、多极形.雷公藤红素与HMC-1细胞在粘附前或粘附后共育均能以剂量和时间依赖方式抑制粘附和粘附过程中细胞形态的变化,并可下调粘附分子的表达.提示:雷公藤红素能抑制HMC-1细胞的粘附,这一作用与其抑制粘附分子表达和细胞形态的改变有关. 相似文献
972.
淋巴细胞经TCR-CD3活化增殖作用的分析 总被引:1,自引:0,他引:1
本文探讨了抗CD3单抗诱导的淋巴细胞活化增殖及有关影响因素。实验结果表明:①淋巴细胞内钙升高是淋巴细胞活化增殖的重要条件,CD3McAb引起的早期胞浆游离钙迅速升高主要由内质网释放钙离子所致,而淋巴细胞增殖不仅需要细胞内钙释放,还需要细胞外钙内流;②GTP结合蛋白是淋巴细胞激活过程的一重要环节,经G蛋白作用物霍乱毒素作用后,淋巴细胞DNA合成显著降低;③新霉素和PSS可抑制PLC和PkC的活性,对淋巴细胞NDA合成造成剂量依赖性抑制作用。此外,抗CD3McAb诱导的淋巴细胞DNA合成需要辅佐细胞的存在,高度纯化的T细胞对CD3McAb的刺激不发生增殖反应。 相似文献
973.
结核性淋巴结炎的组织细胞反应性增生变型 总被引:1,自引:0,他引:1
应用结核杆菌DNA123bp特异性序列片段为靶序列的多聚酶链反应(M·TB-PCR)技术、BCG免疫组化(BCG-IHC)技术和抗酸染色(AF)方法,对38例呈现组织细胞反应性增生-碎屑样坏死-嗜中性白细胞渗出病变的淋巴结石蜡包埋组织进行了分支杆菌/结核杆菌的回顾性检测。三种方法的综合阳性率为52.6%(20/38例)。AF、BCG-IHC和M·TB-PCR的各自阳性率分别为0.8%、26.3%和50%。研究结果表明:(1)在按本文标准选择的淋巴结“组织细胞反应性增生”病变中,有半数病例与结核杆菌的感染有关,即结核性淋巴结炎可呈现“组织细胞反应性增生”之类的变型;(2)PCR技术在结核性淋巴结炎的病原学诊断上具有重要价值。 相似文献
974.
Objective: To investigate the ultra structure of amelanotic melanocytes (AMMC). Methods: The hair follicles obtained from normal human scalp by 0.50% collagenase type V treatment were washed with 0.1mol/L phosphate buffer salt (PBS). Hair-follicle cell suspensions were prepared by trypsin treatment and cultured in melanocyte medium. Remaining keratinocytes were removed by differential trypsinization. 100μg/ml geneticin was used to eliminate the contaminating fibroblasts. At third passage, the cells were trypsinized, and then washed in phosphate-buffered saline and processed for transmission electron microscopy. Results: Under transmission electron microscope, the cultured cells showed round or oval shape, with single large nuclear and the karyotheca were double deck. There were obvious euchromosome within the nucleus, and sparse heterochromosome. There were various organelles in the cytoplasm, including plentiful melanosomes with nearly similar size, mitochondria, rough endoplasmic reticule (RER) and ribosome. The electron density granules in most of the melanosomes disposed along concentric circularities. Golgi apparatus in the cells was inconspicuous. Conclusion: The ultra structure of AMMC from human hair follicles is different from that of epidermal melanocytes, and these characteristics determine the functional immature of AMMC. 相似文献
975.
To compare the differences between proliferation and cytotoxicity of adherent natural killer (A-NK) cells cultured with serum-free medium AIMV and standard serum-containing medium in vitro, and also observe the assisting effect of IL-12 on the activation and the morphology character of IL-2-treated A-NK cells, cellular proliferation was evaluated by MTT method in vitro. The morphology of the target cells killed by A-NK cells was observed through electroscope. All of the A-NK cells cultured in serum-free medium AIMV could rapidly proliferate and keep high cytotoxicity compared with that in standard serum-containing medium. A-NK cells activated by both moderate-dose IL-2 and IL-12 were superior to the high-dose IL-2-treated A-NK cells. These data indicated that serum-free medium AIMV could replace standard serum-containing medium for culturing A-NK cells, and moderate-dose IL-2 and IL-12 could reduce side effects caused by high-dose IL-2. The study provided a new experimental basis for experimental and clinical preparation of A-NK cells. Cellular & Molecular Immunology. 相似文献
976.
41名肢残者十六项人格特质测验 总被引:1,自引:1,他引:1
张丹 《中国心理卫生杂志》1989,3(6):248-249,271
应用“卡特尔十六项人格特质测验问卷”,对41名肢残者和40名健全人进行对照研究。结果表明,肢残人较健全人在孤独性上具有明显的差异,偏于缄默,固执,关注外界信息,具有一定的防卫倾向。肢残人富于实验性,较健全人更自由、激进、好学,具有较强的独立工作能力,希望生活更充实多彩。在各项能力水平上,肢残上与健全人没有显著差别。不同性别肢残人人格特质在敏感性上差异明显,女性较理智和着重现实,而男性则偏于敏感,易感情用事。 相似文献
977.
桡神经及其深支的血供 总被引:1,自引:0,他引:1
在25具成人尸体(50例)上,观测了桡神经及其深支的血供。桡神经的营养动脉平均为4.36±0.26支,营养动脉和来源动脉的外径平均为0.38±0.08mm和1.65±0.05mm。桡神经深支的营养动脉平均为1.72±0.16支,营养动脉和来源动脉的外径平均为0.29±0.01mm和1.91±0.07mm。 相似文献
978.
National examinations for medical graduates were introduced on an experimental basis in the People's Republic of China in 1982. To estimate the predictive validity of the National Medical Examination (NME), an investigation of the postgraduate competence of a sample of the participating examinees was conducted in 1984. The sample consisted of 1,717 of the 4,995 graduates from 13 medical colleges who had taken the initial NME. Their scores on the NME and the ratings given them by directors of postgraduate programs in nine aspects of clinical competence were compared by frequency distribution and product-moment correlation coefficients. Scores on the NME were consistent with measures of postgraduate clinical competence and, as a whole, correlated significantly with the ratings of clinical competence, supporting the use of the score on the NME as a predictor of postgraduate clinical competence. However, the extent of the relationship between the NME score and postgraduate clinical competence varied according to the specialty program of postgraduate medical training. 相似文献
979.
980.
Galactosylated PVDF membrane promotes hepatocyte attachment and functional maintenance 总被引:2,自引:0,他引:2
Lu HF Lim WS Wang J Tang ZQ Zhang PC Leong KW Chia SM Yu H Mao HQ 《Biomaterials》2003,24(27):4893-4903
One of the major challenges in BLAD design is to develop functional substrates suitable for hepatocyte attachment and functional maintenance. In the present study, we designed a poly(vinylidene difluoride) (PVDF) surface coated with galactose-tethered Pluronic polymer. The galactose-derived Pluronic F68 (F68-Gal) was adsorbed on PVDF membrane through hydrophobic-hydrophobic interaction between PVDF and the polypropylene oxide segment in Pluronic. The galactose density on the modified PVDF surface increased with the concentration of the F68-Gal solution, reaching 15.4 nmol galactosyl groups per cm2 when a 1 mg/ml of F68-Gal solution was used. The adsorbed F68-Gal remained relatively stable in culture medium. Rat hepatocytes attachment efficiency on F68-Gal modified PVDF membrane was similar to that on collagen-coated surface. The attached hepatocytes on PVDF/F68-Gal membrane self-assembled into multi-cellular spheroids after 1 day of culture. These attached hepatocytes in spheroids exhibited higher cell functions such as albumin synthesis and P450 1A1 detoxification function compared to unmodified PVDF membrane and collagen-coated surface. These results suggest the potential of this galactose-immobilized PVDF membrane as a suitable substrate for hepatocyte culture. 相似文献