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991.
Cancer is a genetic disorder.Although heredi-tary cancers account for only a small fraction of all tumors,most cancers are caused by a variable mix of heredity and environment that leads to accumulations of genetic alterations and then uncontrolled cell pro-liferations(Kops et al.,2005).In addition,genetic alteration is one of the a few most important bio-logical factors that determine the diagnosis and prognosis of different cancers and dictate the treat-ment strategies for cancer patients.Fu… 相似文献
992.
The mutagemc effects of microwave and chromium trioxide (CrO3) on Vicia faba root tip were studied. Micronucleus assay and chromosomal aberration assay were used to determine the mitotic index, the micronucleus frequency and chromosomal aberration frequency of Vicia faba root tip cells induced by microwave and CrO3. The results showed that the micronucleus frequency decreased, and that the mitotic index and chromosomal aberration frequency showed linear dose responses to CrO3, in treatment of microwave for 5 s. In microwave of 25 s, the mitotic index decreased, the micronucleus frequency and chromosomal aberration frequency increased with increase of CrO3 concentration. We concluded that microwave and CrO3 had antagonistic effect on the mitotic index of Vicia faba root tip cells, but had synergetic effect on micronucleus frequency and chromosomal aberration frequency of Viciafaba root tip cells. 相似文献
993.
Ruan WJ Lin J Xu EP Xu FY Ma Y Deng H Huang Q Lv BJ Hu H Cui J Di MJ Dong JK Lai MD 《Journal of Zhejiang University. Science. B》2006,7(11):929-932
Insulin-like growth factor binding-protein-7 (IGFBP7) was obtained from our previous colonic adenocarcinoma (CRC) and normal mucosa suppression subtraction hybridization (SSH) cDNA libraries. By RT-PCR and immunohistochemistry, we found that IGFBP7 was overexpressed in CRC tissue compared to normal tissue. However, our in vitro experiments performed in 10 CRC cell lines showed that IGFBP7 expressed only in SW480 and Caco2 cell lines, which implied an underlying reversible regulatory mechanism. Using methylation-specific PCR (MSP) and bisulfite sodium PCR (BSP), we found that its expression was associated with DNA hypomethylation of exonl. This was further supported by the in vitro study which showed restored IGFBP7 expression after demethylation agent 5-aza-2'-deoxycytidine treatment. Correlation analysis between IGFBP7 expression and prognosis indicated that overexpression of IGFBP7 in CRC tissue correlated with favourable survival. Investigation of the functional role of IGFBP7 through transfection studies showed that IGFBP7 protein could inhibit growth rate, decrease colony formation activity, and induce apoptosis in RKO and SW620 cells, suggesting it a potential tumor suppressor protein in colorectal carcinogenesis. In conclusion, our study clearly demonstrated that IGFBP7 plays a potential tumor suppressor role against colorectal carcinogenesis and its expression is associated with DNA hypomethylation of exon 1. 相似文献
994.
A probiotic treatment containing Lactobacillus, Bifidobacterium and Enterococcus improves IBS symptoms in an open label trial 总被引:7,自引:0,他引:7
INTRODUCTION Irritable bowel syndrome (IBS) is the most common functional gastrointestinal disorder. The typical symptoms are abdominal pain, flatulence, and irregular bowel movement. Prevalence rates are re- ported to be as high as 30% in the general population (Drossman et al., 1982), corresponding to about 25%~50% of all patients who need gastroenterolo- gist’s help (Everhart and Renault, 1991). Despite this high prevalence, the cause of IBS is unknown. Many factors are likely to … 相似文献
995.
INTRODUCTION In 1998 gastrointestinal pathologists reached aconsensus on the definition of chronic atrophic gas- tritis (CAG), which was described as programmed loss of gastric gland and/or replacement by intestinal glands in gastric mucosa. CAG was recognized to be closely related with development of gastric cancer and listed as precancerous lesions in this meeting (Genta, 1998). According to Correa (1992)’s cascade of gas-tric carcinogenesis, gastric cancer was believed to develop fr… 相似文献
996.
Edaravone protects PC12 cells from ischemic-like injury via attenuating the damage to mitochondria 总被引:6,自引:0,他引:6
Background: Edaravone had been validated to effectively protect against ischemic injuries. In this study, we investigated the protective effect of edaravone by observing the effects on anti-apoptosis, regulation of Bcl-2/Bax protein expression and recovering from damage to mitochondria after OGD (oxygen-glucose deprivation)-reperfusion. Methods: Viability of PC 12 cells which were injured at different time of OGD injury, was quantified by measuring MTT (2-(4,5-dimethylthia-zol-2-yl)-2,5-diphenyltetrazolium bromide) staining. In addition, PC 12 cells' viability was also quantified after their preincubation in different concentration of edaravone for 30 min followed by (OGD). Furthermore, apoptotic population of PC 12 cells that reinsulted from OGD-reperfusion with or without preincubation with edaravone was determined by flow cytometer analysis, electron microscope and Hoechst/Pl staining. Finally, change of Bcl-2/Bax protein expression was detected by Western blot. Results: (1) The viability of PC12 cells decreased with time (1-12 h) after OGD. We regarded the model of OGD 2 h, then replacing DMEM (Dulbecco's Modified Eagle's Medium) for another 24 h as an OGD-reperfusion in this research. Furthermore, most PC 12 cells were in the state of apoptosis after OGD-reperfusion. (2) The viability of PC 12 cells preincubated with edaravone at high concentrations (1, 0.1, 0.01 μmol/L) increased significantly with edaravone protecting PC 12 cells from apoptosis after OGD-reperfusion injury. (3) Furthermore, edaravone attenuates the damage of OGD-reperfusion on mitochondria and regulated Bcl-2/Bax protein imbalance expression after OGD-reperfusion. Conclusion: Neuroprotective effects of edaravone on ischemic or other brain injuries may be partly mediated through inhibition of Bcl-2/Bax apoptotic pathways by recovering from the damage of mitochondria. 相似文献
997.
The binding of pefloxacin mesylate (PFLX) to bovine lactoferrin (BLf) and human serum albumin (HSA) in dilute aqueous solution was studied using fluorescence spectra and absorbance spectra. The binding constant K and the binding sites n were obtained by fluorescence quenching method. The binding distance r and energy-transfer efficiency E between pefloxacin mesylate and bovine lactoferrin as well as human serum albumin were also obtained according to the mechanism of Forster-type dipole-dipole nonradiative energy-transfer. The effects of pefloxacin mesylate on the conformations of bovine lactoferrin and human serum albumin were also analyzed using synchronous fluorescence spectroscopy. 相似文献
998.
回顾了地图投影变换的基本方法,阐述连续型遗传算法和遗传规划的原理和方法,探讨这两优化方法在地图投影变换中的应用. 相似文献
999.
《太平御览》征引了古代经史子集书2800多种。引文按照全书所分的55部编排,全部引文遵循中心词突出的方法,围绕各类目选择材料。同时,根据引文出现的不同位置和作用,编者还运用了互见法、又见法和存异法等。 相似文献
1000.