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991.
992.
应用~(51)Cr释放试验和效靶结合试验,同时测定了正常人和胃癌病人外周血NK细胞活性与靶结合细胞数(TBC),研究了正常人及病人血浆对NK细胞功能的影响。发现正常人NK细胞活性与靶结合细胞数之间的关系呈直线正相关,但在NK活性降低的病人中靶结合细胞数却无明显改变,二者无相关性,而病人的血浆对正常人外周血NK活性则有明显的抑制作用(P<0.05),且抑制率与胃癌人NK细胞活性存有着负相关的关系,提示胃癌病人血浆具有抑制NK细胞活性的物质。 相似文献
993.
V. Ventafridda E. Oliveri A. Caraceni E. Spoldi F. De Conno L. Saita C. Ripamonti 《Journal of pain and symptom management》1987,2(2):77-81
The authors report a retrospective study of 390 cancer pain patients tested with oral morphine during a four-month period. Initial pain scores were reduced to one half after one week of treatment and then maintained throughout the study period. Mean daily dosages of morphine were lower in those patients 65 years and older. No significant changes in performance in relation to therapy were noted except for an increase in hours of sleep. An accurate titration of dosage and continued control of side effects are the main requirements of this method of administration. The presence of side effects and the cause of interruption of treatment are reported. 相似文献
994.
本文对食管癌高、低发区食管癌患者和正常人,经MNNG诱导的DNA损伤修复功能进行了研究。实验采用外周血淋巴细胞培养的方法。每组又分为对照组及MNNG诱导组。样品以~3H-TdR标记后经液闪仪计数法进行检测。结果发现,低发区正常人经MNNG诱导的DNA损伤修复功能明显高于对照组,两个地区食管癌患者修复能力均低于正常人,与地区无关。 相似文献
995.
Convergence of Genetic, Nutritional and Inflammatory Factors in Gastrointestinal Cancers 总被引:2,自引:0,他引:2
Gastrointestinal cancers account for 20% of all cancer incidences worldwide. Colorectal cancer is the second most common cause of all cancer-related mortality and is increasing in Western societies. Infection and inflammation contribute to 15–20% of all malignancies, and are predisposing risk factors for gastrointestinal cancers. Helicobacter pylori infection is commonly associated with gastric cancers, and chronic inflammation increases the risk of colorectal cancer by 1% per year. Micronutrient status and common genetic variations in human populations modify risk for gastrointestinal cancer. Chronic inflammation promotes carcinogenesis by inducing gene mutations, inhibiting apoptosis, and stimulating an-giogenesis and cell proliferation. Inflammation also induces epigenetic alterations that are associated with cancer development. Two key genes in the inflammatory process, cyclooxygenase-2 (COX-2) and nuclear factor-kappa B (NF-kB), provide a mechanistic link between inflammation and cancer and are targets for chemoprevention. Dietary components, and human genetic variation that affects nutrient utilization, can directly modify inflammatory processes and/or suppress genomic alterations that are the molecular antecedents of cancers. The present report focuses on the convergence of genetic, nutritional, and inflammatory factors in the initiation and progression of gastrointestinal cancers, and the emerging dietary strategies for cancer prevention. 相似文献
996.
本文就福建省及长乐县全死因回顾调查资料,应用Poisson分布原理分析胃癌死亡人群分布特征。福建省资料x~2=34.9330,P<0.001,不符合Poisson分布,提示全省有高低发区存在。长乐县X~2=0.9312,P>0.05,符合Poisson分布,即胃癌在该县呈高度分散状态,恶性肿瘤的地区分布和致癌因素分布相一致。 相似文献
997.
Mortality among ferrous foundry workers 总被引:8,自引:0,他引:8
M Silverstein N Maizlish R Park B Silverstein L Brodsky F Mirer 《American journal of industrial medicine》1986,10(1):27-43
Mortality analyses were carried out for 278 male hourly workers who were employed for at least 10 years at a gray iron foundry and who died between January 1, 1970 and December 31, 1981. Statistically significant excess proportional mortality due to non-malignant respiratory disease (SPMR = 177), lung cancer (SPMR = 148), and leukemia (SPMR = 284) was found among the 221 white males. Among nonwhite males there was a significant excess in proportional mortality due to circulatory diseases (SPMR = 143). White males in the Finishing classification experienced a significant excess of proportional mortality due to nonmalignant respiratory disease (SPMR = 279) and lung cancer (SPMR = 179). White males in the Core Room classification experienced an excess of proportional mortality due to nonmalignant respiratory disease (SPMR = 321). Case-control studies demonstrated a significant association between nonmalignant respiratory disease and the Finishing classification after controlling for the effects of age, prior occupations in coal mining or foundries, and smoking. A positive but nonsignificant association between lung cancer and Finishing was also found after controlling for age, prior work history, and smoking in case control studies. 相似文献
998.
Although knowledge of functional differentiation and tumour-associated changes of breast carcinomas can be gained by the application of antibodies directed against the milk fat globule membrane, more significant information may be obtained by assessment of the potential of breast carcinomas to modulate their antigenic phenotype. In this study, the extend to which primary tumours can undergo modulation in vitro has been investigated, with consideration of the suitability of organ culture in combination with the immunohistochemical detection of two milk fat globule membrane epitopes, HMFG1 and HMFG2, as methods for detecting this. The preservation of three of the 30 carcinomas assessed, all poorly differentiated, was poor after 3 days of culture. The viability of the other 27 was variable, and was greater in the better differentiated tumours and with the addition of insulin. Expression of the milk fat globule membrane epitopes was generally well maintained. Six of the carcinomas showed a significant change in antigen expression, with this being more frequent in tissues incubated with insulin. Hence, a small group of carcinomas have been identified which appear to have a greater capacity to undergo functional differentiation. Organ culture is considered to be a suitable method for maintaining the tissues in vitro for such evaluation, but the problems encountered in quantifying the immunohistochemical staining, because of antigenic heterogeneity, were such that it is suggested that other approaches be employed. 相似文献
999.
拓扑替康在卵巢癌治疗中的新进展 总被引:1,自引:0,他引:1
拓扑替康是一种新的半合成喜树碱衍生物 ,通过抑制拓扑异构酶Ⅰ而产生抗肿瘤作用。大量研究表明拓扑替康对卵巢癌尤其是经铂类药物化疗失败 ,复发的卵巢癌患者有较好疗效。本文就拓扑替康在卵巢癌临床应用中的新进展进行综述。 相似文献
1000.