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22.
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
23.
目的 为了解中日儿童及成人的步行和体成分及其相互关系.方法 以中国上海市和日本琦玉县的小学生和成人为对象,采用西铁城 TW02-001电子式步数计测定步行量,FUTREX-5000A体成分测定仪测量体脂百分比.结果 1.中国男女小学生的平均每日步行量分别为12426步和10387步,低于日本小学生(男15 340步,女11 617步),体脂百分比中国男女生分别为21.2%和15.8%,高于日本(男18.9%,女13.1%).中国男女成人的平均每日步行量分别为9826步和8748步,高于日本成人(男:8411步,女7599步);体脂百分比分别为17.5%(男)和25.8%(女),而日本男性为19.8%,女性为26.0%.2.不同活动水平的小学生和成人,其血压和体成分均有差异,步行量高者的血压和体脂百分比都较低.本研究还计算出以肱三头肌皮脂厚度以(X)推测儿童体脂百分比(Y)的回归方程为:Y=10.6646+0.5856X.结论 作为日常生活的步行可促进肥胖发生率的降低. 相似文献
24.
"Chronic painter''s syndrome". A reanalysis of psychological test data in a group of diagnosed cases, based on comparisons with matched controls 总被引:4,自引:0,他引:4
Twenty solvent-exposed workers, most of them painters, had been diagnosed as cases of toxic encephalopathy in 1978/79. Two years later they were re-examined with an extensive battery of neuropsychological tests. Their performance was unchanged on retesting. We have now compared their test results with those of non-exposed control subjects. Previous impressions of significant intellectual impairment in the solvent-exposed patients could not be confirmed when the influence of age, education, and intelligence was taken into consideration. The present group with presumed toxic encephalopathy is assumed to be representative of other patients who were similarly diagnosed in our department. The presently reanalyzed cases had been diagnosed as brain damaged and reported as such in the literature. Thus, they may have contributed to the formation of the concept of the "chronic painters' syndrome" with dementia. 相似文献
25.
This paper reviews the literature on the role of dietary fat in calorie intake and body weight gain in humans and laboratory animals. An overview of 40 animal studies which compared growth on high-fat (HF) and high-carbohydrate (HC) solid/powdered diets indicated that the HF diet elicited greater weight gain in 33 out of 40 studies. Enhanced growth on the HF diet was often, but not exclusively, attributable to greater caloric intake. Additional evidence for the growth-enhancing effect of HF diets emerges from "diet option" and "supermarket" feeding studies in rats, and experimental and epidemiological studies in humans. Three principal factors that contribute to the different responses to HF and HC diets are (a) caloric density, (b) sensory properties and palatability, and (c) postabsorptive processing. It is concluded that both calorie intake and metabolic energy expenditure are biased towards weight gain when a HF diet is consumed, and that the high caloric density of high-fat diets plays a primary role in weight gain. Humans may be biologically predisposed to gain weight when a HF diet is consumed. 相似文献
26.
G. Winkled A. Döring U. Keil P. Pietinen D. Arveiler J. P. Cambou C. Nuttens J. L. Richard A. Evans R. McClean E. McCrum 《Journal of molecular medicine (Berlin, Germany)》1992,70(10):889-895
Summary The composition of diet and food intakes in four selected European populations were compared. Dietary data (from the World Health Organization Project on Monitoring Trends and Determinants in Cardiovascular Disease) were measured by record methods and were available for middle-aged men in Finland (n = 653), France (n =1128), Northern Ireland (n = 356), and southern Germany (Augsburg region; n = 899). Nutritional variables — which are independent of the absolute energy intake, such as the percentage supply of energy from macronutrients and the ratio of polyunsaturated to saturated fatty acids — were on the whole similar. However, striking differences were found in food intake and in the percentage supply of fat from different foods. The results indicate that detailed knowledge of consumption figures is necessary to develop prudent and acceptable nutrition intervention programs.Abbreviations CHD
coronary heart disease
- MONICA
monitoring trends and determinants in cardiovascular disease
- MUFA
monounsaturated fatty acids
- P/S ratio
ratio of polyunsaturated fatty acids/saturated fatty acids
- PUFA
polyunsaturated fatty acids
- SFA
saturated fatty acids 相似文献
27.
Toshio Nishimura Keizo Tsuruhara Keiko Naito Junko Hirohara Sotokichi Morii 《Pathology international》1989,39(5):281-288
To examine the effect of colchicine on ethionine induced fatty liver, adult female rats were starved overnight and then injected i.p. with 1 g kg ethionine at 11th hour of fasting; then a half of the rats were also injected i.p. with 2.5 mg kg colchicine twice at 3 and 6 h after the single administration of ethionine. Similarly, fasted control rats were injected i.p. with vehicle alone at the above times. All of the rats were sacrificed after a 20 h fast, and the hepatocytes in periportal areas were observed ultra-structurally. In addition, total lipids in the liver tissue were extracted and determined biochemically. Although similar significant increases of triglyceride were observed in the liver tissue of all ethionine-injected rats, the hapatocytes in the group treated with both chemicals had fewer cytoplasmic fat globules (CFG) than those in the group treated with ethionine only. On the other hand, the diameters of markedly increased membrane-bound lipid particles (MLP) in the double treated group were distributed mainly in the range 0.2–0.4 μm, compared with those (0.1-0.2 μm) in the other groups. These findings indicate that colchicine inhibits the development of CFG in ethionine injured hapatocytes. Acta Pathol Jpn 39: 281∼288, 1989. 相似文献
28.
利用光镜、电镜、免疫组化和形态学定量技术动态研究维生素A对大鼠四氯化碳肝纤维化的抑制作用。结果表明,维生素A可减少四氯化碳中毒大鼠肝内纤维连接蛋白和Ⅰ、Ⅲ型胶原沉积,抑制贮脂细胞向成纤维细胞转化,并可明显地减轻肝纤维化程度。本文还对维生素A抑制肝纤维化的机理及意义作了初步探讨。 相似文献
29.
Michael H. Stone Michael E. Rush Harry Lipner 《Pflügers Archiv : European journal of physiology》1978,375(2):147-151
The hormonal levels of the gonadotropins, the weight of selected organs and of the triceps surae as well as body composition were determined in Sprague Dawley rats at 3 and 6 weeks after intensive training with or without a methandrostenelone (Dianabol) supplement (0.35 mg/kg/day). The controls were sedentary rats of similar age and weight at the start of the experiment. The dianabol treated rats in the sedentary and exercise groups had a depression of plasma LH levels. There were no differences in body weight, specific gravity, lean body weight, fat or % fat between the two trained groups. Dianabol had no apparent effect on the measured parameters other than a depression of LH. 相似文献
30.
BACKGROUND: Low-dose flutamide-metformin has been developed as a background therapy for non-obese adolescents and young women with hyperinsulinaemic hyperandrogenism, a variant of polycystic ovary syndrome (PCOS). We verified whether the lipolytic efficacy of flutamide-metformin in women with PCOS is enhanced by giving an oral contraceptive (OC) co-therapy that contains drospirenone, instead of gestodene, as progestin. METHODS: An open-labelled study was carried out in which non-obese women with PCOS (n = 29; age approximately 20 years), who had been on a combination of flutamide (62.5 mg/day), metformin (850 mg/day) and ethinylestradiol-gestodene for 8-15 months, were randomized for replacement of the gestodene OC by a drospirenone OC. Assessments of endocrine-metabolic state and body composition (by dual-energy X-ray absorptiometry) were performed at randomization and after 6 months. RESULTS: The switch to drospirenone OC was accompanied by a reduction of total and abdominal fat (mean -0.8 and -0.5 kg) and by an increment of lean body mass (+0.6 kg; all P < 0.01), so that body adiposity was strikingly reduced without changing body weight. CONCLUSION: In non-obese women with PCOS, low-dose flutamide-metformin reduces total and abdominal fat excess more effectively if contraceptive co-therapy contains drospirenone, instead of gestodene, as progestin. 相似文献