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91.
The work gives substantiation of using complete intestinal lavage for certain indications in the complex treatment of incompetent colonic anastomoses. The method was efficiently used in 6 patients. 相似文献
92.
Assessment of caffeine exposure: caffeine content of beverages, caffeine intake, and plasma concentrations of methylxanthines 总被引:4,自引:0,他引:4
The caffeine content of all tea or coffee beverages consumed by 17 healthy adults over 24 hours was measured. Plasma caffeine, theophylline, theobromine, and paraxanthine concentrations were determined over the same 24 hours. The average caffeine content per drink was 60.4 +/- 21.8 mg for instant coffee (14-fold range), 80.1 +/- 19.2 mg for brewed coffee (2.8-fold range), and 28.8 +/- 13.7 mg for tea (5.5-fold range). The number of drinks of coffee and tea consumed was a poor index of actual caffeine intake (r2 = 0.42). Caffeine intake correlated poorly with the 24-hour average caffeine concentration (r2 = 0.41), but there was a very good correlation between a single plasma caffeine concentration measured at 5 PM and the 24-hour average concentration (r2 = 0.94). The same was true for paraxanthine (r2 = 0.86). Paraxanthine accounted for 67.3% of the total dimethylxanthines in plasma, while theobromine and theophylline accounted for 24.4% and 8.3%, respectively. Mean caffeine clearance was 1.2 +/- 0.3 ml/min/kg. Plasma caffeine concentration before the first drink in the morning correlated very poorly with caffeine clearance (r2 = 0.07), even when adjusted for caffeine intake (r2 = 0.21). 相似文献
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R N Chunge P N Karumba N Nagelkerke N Kaleli M Wamwea N Mutiso E O Andala S N Kinoti 《East African medical journal》1991,68(2):112-123
A cross-sectional survey of intestinal parasitic infection in a rural community, Nderu, in Kiambu District, Kenya, was carried out in 1985 by examining 1129 individuals from 203 households (about 25% of the total population). This was followed by 3 more cross-sectional surveys, in January, May and October 1986, of 56 families comprising 461 individuals, who had also participated in the first survey. In the first survey, 81.4% of the sample was positive for at least one intestinal parasite and 78% was positive for intestinal protozoa. 72.7% of those infected had multiple infections. The prevalence of most of the protozoa increased with age but that of Giardia lamblia peaked in the 0 to 4 year class at 35.5%. Females were infected more often with several of the protozoa, but males with Ascaris. People living in larger households were more often infected with Entamoeba histolytica and Iodamoeba butschlii, while the opposite was true of H. nana and tended to be for Giardia. Significant positive associations between parasite species were common at all surveys, especially among the amoebae. The majority of negative associations were for Giardia. Unformed stools were significantly associated with Giardia, Blastocystis, and trophozoites of Trichomonas hominis and Chilomastix mesnili. Endolimax nana and Entamoeba coli were found more often in formed stools. Estimates of daily incidence, and duration of infection in days, were calculated for 11 parasites. The longest mean estimated duration of infection for any species was 237 +/- S.D. 151.4 days for H. nana and the shortest was 41.6 +/- S.D. 0.4 days for T. hominis. 相似文献
96.
'Gliosarcomas' have long been considered to be mixed gliomas and sarcomas. The present study failed to define criteria which clearly delineate 'gliosarcomas' from glioblastoma multiforme and suggests that 'gliosarcomas' should be considered as spindle cell glioblastomas. A total of six cases originally diagnosed as 'gliosarcomas' were compared with four cases of glioblastoma multiforme. No clinical or prognostic features were defined which would clearly separate 'gliosarcomas' from glioblastoma multiforme. Macroscopically, biopsies from 'gliosarcomas' ranged from firm, apparently well-circumscribed tumours to poorly circumscribed lesions with a soft consistency resembling glioblastoma multiforme. Histology revealed a continuous spectrum in which 'gliosarcomas' with large reticulin-rich areas of spindle cells merged with typical glioblastomas containing only small islands of spindle cells and reticulin staining. Immunocytochemistry for glial fibrillary acidic protein (GFAP); S100 protein and alpha-smooth muscle actin (ASMA) showed that the majority of cells in reticulin-poor areas of 'gliosarcoma' and glioblastomas expressed S100 protein and GFAP; many expressed ASMA and some expressed both GFAP and ASMA. Spindle cells in reticulin-rich areas of 'gliosarcomas' and glioblastomas most frequently expressed ASMA but many cells also expressed S100 protein and GFAP; some cells expressed both GFAP and ASMA. The results of this study and a review of the literature suggests that there is a clinical, radiological and pathological continuum with glioblastoma and 'gliosarcoma' at different ends of the spectrum. It is suggested, therefore, that most, if not all, 'gliosarcomas' be redesignated as spindle cell glioblastomas and not be considered as a mixture of glioma and sarcoma. 相似文献
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To evaluate the relative contribution of insulin binding and postbinding defects of glucose utilization in peripheral tissue during normal and diabetic pregnancy, we have studied the in vitro insulin action of isolated adipocytes from eight nondiabetic pregnant women and nine pregnant women with insulin-dependent diabetes mellitus who were undergoing cesarian section. The pregnant women were compared with a matched group of normal nonpregnant women undergoing gynecologic surgery. Insulin binding to adipocytes measured at tracer insulin concentration was reduced by 45% (P less than 0.01) in normal pregnant women and by 30% (P less than 0.02) in pregnant women with diabetes. In contrast, no changes were found between the three groups in insulin binding to pure monocytes and erythrocytes. The glucose transport system in fat cells from both groups of pregnant women was characterized by impaired maximal (P less than 0.05) and half-maximal (P less than 0.05) response to insulin. When fat cell glucose metabolism was studied, pregnant diabetic women exhibited decreased basal lipogenesis (P less than 0.05) and decreased maximal responses of lipogenesis and glucose oxidation to insulin stimulation (P less than 0.05). Similar but less pronounced abnormalities were seen in glucose metabolism of adipocytes from nondiabetic pregnant women. In conclusion, both in late normal and diabetic pregnancy, insulin binding to adipocytes is significantly reduced and accompanied by decreased insulin sensitivity and reduced maximal insulin responsiveness of glucose transport and by impaired basal and maximally insulin-stimulated glucose metabolism. 相似文献