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71.
AIM: To assess the effect of indomethacin on tumor invasion in a human laryngeal cancer Hep-2 cell line in vitro. METHODS: Hep-2 cells were exposed to indomethacin at different concentrations for 48 h. Then cell growth rate, the colony formation in soft agar medium and cell mobility were examined, and monolayer invasion assay was performed to assess cell invasion index. RESULTS: Preteatment with indomethacin inhibited the colony formation of Hep-2 cells and the cell mobility, and decreased the invasion index. CONCLUSION: Indomethacin can inhibit the invasion of Hep-2 cells. 相似文献
72.
AIM: To investigate the effect of Sini decoction (SND)on the ultrastructure of small intestinal epithelial cells in rats with intestinal ischemia-reperfusion. METHODS: Thirty-two Sprague-Dawley rats of both sexes were randomly divided into 4 groups: (1) Control group in which sham operation was performed; (2) Model group in which intestinal I/R was produced by clamping super mesenteric artery(SMA) for 1 hour and declamping SMA for 3 hours; (3) SND1 group in which SD (0.6 g/200 g rat) was given via stomach tube 3 d before intestinal I/R; (4) SND2 group in which SD (1.2 g/200 g rat)was given via stomach tube 3 d before intestinal I/R. A strip of small intestine was taken from distal end of ileum for electron microscopic examination. The two-dimensional structural parameters and three-dimensional structural parameters of mitochondria were calculated. RESULTS: (1)Morphological changes of small intestine: In control group, epithelial cells were orderly arranged, with normal mitochondria and intestinal villi. In model group, the gaps between epithelial cells widened. There were a lot of apoptotic cells. Microvilli were short and swelled. Mitochondria were swelled obviously with broken ridges. Endoplasmatic reticulum was severely dilated. In SND1 and SND2 groups, microvilli and epithelial cells were orderly arranged relatively, mitochondria was slightly swelled. (2) Structural parameters of mitochondria: In model group, there were the least mitochondria and the swelling of mitochondria was severe. In SND1 and SND2 groups, the mitochondria was more than that of model group and the swelling were slight. CONCLUSION: Sini decoction can protect small intestine from ischemia-reperfusion injury without dose-dependent effect. 相似文献
73.
Endothelial progenitor cell (EPC) is a kind of directional cell that is able to differentiate to endothelial cell. The role of EPC is associated not only with vasculogenesis during embryonic development but also with physiological organ maintenance and angiogenesis during postnatal and adult period. There is a good clinical therapeutic prospective use for EPC in the treatment of ischemia diseases and inhibition of tumor angiogenesis. 相似文献
74.
AIM: To examine the effects of inhibition of Kupffer cell and splenectomy on intestinal endotoxemia and hepatic injury. METHODS: The hepatic injury model was established by treatment with thioacetamide (TAA). At the same time, inhibition of Kupffer cells by intravenous GdCl3 and splenectomy were performed. Serum alanine aminotransferase (ALT), TNF-α, endotoxin content and phagocytic index were observed. RESULTS: In the TAA+GdCl3 group, and TAA+splenectomy group, the endotoxin content was significently higher than that in normal and TAA group (P<0.05). The plasma TNF-α, ALT and total bilirubin were significantly lower than those in TAA group (P<0.05). CONCLUSION: Inhibition of Kupffer cells and splenectomy increase plasma endotoxin level, but decreases the plasma TNF-α levels and alleviates the hepatic injury induced by TAA. 相似文献
75.
Mesenchymal stem cells (MSCs) are a population of multipotent cells that can proliferate and differentiate into marrow and non-marrow cell types, such as adipocytes, chondrocytes, myocytes, and so on. In recent years, many researchers have studied whether MSCs are capable of differentiation into neurons in vivo and ex vivo. The result that MSCs-derived neurons express NSE and NF, but don't express GFAP suggests MSCs can differentiate into neurons, some researchers have achieved success in promoting functional recovery in Pakinsons and transactional spinal cord injury rat models by use of MSCs-derived neurons. Therefore, MSCs-derived neurons will play an important role in the therapy for a variety of diseases of the nervous system. 相似文献
76.
Angiopoietin-1 (Ang-1) is a newly-found endothelium-specific proangiogenic factor and it had been proved essential roles in both vasculogenesis and angiogensis. Among them, its anti-leakage ability may have great potential applications in clinical treatment of vascular hyper-permeability in a variety of diseases such as cancer, diabetic retinopathy, rheumatoid arthritis, asthma. In this review, some research progresses focused on this aspect are discussed. 相似文献
77.
78.
猪原始生殖嵴细胞(PGCs)建系因素的研究 总被引:4,自引:3,他引:4
从五指山猪(WSZP)近交系第8~13代培育群中,先后选用21头5~10月龄青年母猪,分别于授精后25~30d采集胎儿106个,进行原始生殖嵴(PGCs)细胞分离、培养等建系技术研究。以DMEM F10(1:1)为基础培养液,按添加或不添加生长因子,将培养液分为A、B、C3种,并以STO细胞作饲养层,在38℃、5.0%CO2和湿润的气相中进行培养建系。结果获得胚胎生殖嵴细胞(EG)细胞系6个细胞株,其中1个EG细胞株传至11代、2个传至5代、1个传至4代、2个传至3代冻存。并进行了AKP染色、体外分化、冷冻-解冻复苏和嵌合体制作等鉴定研究。研究发现:不同胚龄对EG细胞建系具有一定影响,不同培养液对EG细胞建系效果不同,STO细胞饲养层的质量是建株、传代、冷冻-解冻复苏的关键因素之一。EG细胞系的初步建立,为今后筛选进入种系的EG细胞系、实施体外基因操作提供了可能。 相似文献
79.
U. Merz V. Martinez R. Schwärzel 《European journal of plant pathology / European Foundation for Plant Pathology》2004,110(1):71-77
Powdery scab of potato, once established in a field, is difficult to control because of the longevity of the resting spores (cystosori) of the causal organism, Spongospora subterranea f.sp. subterranea. Host resistance is likely to be the most efficient in a long-term control strategy for preventing build-up of field inoculum and spread of the disease. Resistance screening of potato cultivars is mostly done in laborious field trials where disease development is likely to be unpredictable. A bioassay with potato tissue cultured plantlets and cystosori as inoculum is described and was tested for its potential to screen potato cultivars at an early stage for their relative susceptibility to powdery scab by comparing the lab results with field data. With cystosori inoculum of Swiss origin, the laboratory test showed clear differences between the potato cultivars in the severity of zoosporangial root infection which correlated better with ranked tuber infection data, compared to root galling. There are apparent differences in the relative trends in susceptibility between roots and tubers of five selected cultivars when using naturally infested soil instead of prepared cystosori as inoculum in the lab bioassay. Furthermore, differences in the severity of zoosporangial root infection of two selected cultivars were found when cystosori from different countries where used as inoculum. A possible host genotype × pathogen interaction is discussed. The bioassay has the potential to screen and select for resistant material at an early breeding stage thus making field trials not unnecessary but more economical. It will allow the use of a standard set of pathogen collections and facilitate testing for inoculum virulence in infested soils. 相似文献
80.