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961.
Lepromatous leprosy is characterized by immune anergy and abnormal suppressor T-cell function. Contrasuppressor cells are a subset of CD8+, vicia villosa-adherent T lymphocytes. T-contrasuppressor (Tcs) cells act on T-helper cells to cause them to become unresponsive to the action of T-suppressor cells. In 8 lepromatous (LL) and 7 tuberculoid (TT) patients, and 6 healthy contacts we studied the percent of the following lymphocyte subsets: CD3+, CD4+, CD8+, Ia+, vicia villosa+ (VV+), CD8, VV+, VV, Ia+, and Ia, Tac+. This was done in baseline status as well as post-stimulation with recombinant gamma interferon (rIFN-gamma). We found that peripheral blood mononuclear cells from LL and TT patients and controls exhibit a similar number of putative contrasuppressor lymphocytes (CD8, VV+ cells). However, in the contrasuppressor subset from LL patients we found a low percent of Ia+ (p less than 0.05 compared to controls or TT). In the three groups studied, the rIFN-gamma enhanced the percent of Ia+ lymphocytes in the CD8, VV+ cell subpopulation. However, the CD8, VV+ lymphocytes from LL patients, despite the effect of rIFN-gamma, continue to have a low percent of Ia+ cells (p less than 0.05 compared to controls or TT). These findings suggest that LL patients might have abnormalities in the contrasuppressor immune circuit. Future functional studies on the role of Tcs cells in the anergy seen in LL will be required in order to define the apparent dysfunction occurring in this disease.  相似文献   
962.
963.
964.
The presence of cellular retinoic acid binding protein (cRABP) was analyzed in 13 consecutive patients with large bowel cancer (one right colon and 12 rectum-sigmoid, classified as three Duke B, eight C, and two D). Specimens of neoplastic tissue and of adjacent mucosa were obtained at surgery, and cRABP was determined by an assay based on incubation of partially purified cytosol with labeled retinoic acid and ultracentrifugation in sucrose density gradients. Sixty-one percent of tumors contained detectable levels of cRABP, whereas 58.3% of normal mucosal specimens were positive for cRABP. Among the positive tumors 62.5% contained cRABP also in the corresponding mucosa; in the group of cRABP-negative tumors, 40% showed cRABP in the adjacent mucosa. No correlation could be established with the grading or the stage of the tumors; however, interestingly, 100% (three cases) of gelatinous carcinomas were cRABP positive. Since cRABP seems to be a character of neoplastic cells contrary to normal ones, it would be interesting to investigate the conditions that influence the presence of this protein in normal appearing mucosa adjacent to carcinoma.  相似文献   
965.
Studies were performed in hypercholesterolemic rabbits to determine whether the hydrophobic surfactant, Poloxalene 2930 (Pol), is of benefit under these conditions. Lipoprotein analyses plus chemical and morphologic studies of the aorta were performed to evaluate the results. In one study, rabbits were made hypercholesterolemic by dietary means and then divided into two groups and given a cholesterol-free diet with one group additionally given Pol with treatment continued for 10 weeks. Pol treatment resulted in less atherosclerosis but the mechanism for this effect was not apparent from lipoprotein analysis. In the other study 3 groups of rabbits were given a cholesterol-rich diet for 16 weeks. Two groups received Pol supplement with one of these groups receiving a dose that was too small to prevent hypercholesterolemia. In this group plus the group on diet alone comparable degrees of hypercholesterolemia were maintained throughout the study. Lipoprotein abnormalities were similar in these two groups except that those on Pol had a more normal cholesterol to apolipoprotein B ratio. The amount of atherosclerosis in both groups was mild but aortic cholesterol content was much less for the Pol group. It is concluded that Pol limits cholesterol accumulation in the aortic wall of hypercholesterolemic rabbits and can retard the development of atherosclerosis.  相似文献   
966.
Biliopancreatic diversion is a very effective method for weight reduction. In some instances it is too effective and needs to be revised.  相似文献   
967.
968.
Changes in the height, weight, body mass index, triceps skinfold, and arm and estimated midarm muscle circumferences in lower socioeconomic Mexican American children, 6 through 17 years of age, from Brownsville, Texas, were documented on the basis of surveys done in 1972 and 1983. With the exception of height in youths ages 14-17, all parameters show gains at most ages, and in particular an increase in fatness. Brownsville Mexican American youth are similar in height, weight, and the body mass index to Mexican American youth in other areas of Texas. These trends confirm the large proportion of relatively short but heavy children among Mexican Americans.  相似文献   
969.
In 1983, 1623 primary and secondary schoolchildren took part in a health survey which was organized by the Busselton Population Studies Group. Age, sex, weight, height and country of birth were recorded for each child. Where possible, the country of birth of parents and the occupation of the father were extracted from previous Busselton surveys of adults. Compared with Perth schoolchildren, the difference in the attained weight and height of Busselton children at any age was small. This was so even though the two communities differ in location (rural compared with metropolitan), in ethnic origin (mainly British compared with diverse origins) and, probably, in social-rank distribution. Data from the two communities showed that a similar small secular increase in height had occurred since 1970/1971. This increase averaged at 1.2 cm for children at each year of age in Busselton and 1.5 cm to 1.6 cm for children in Perth.  相似文献   
970.
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