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Several methods for demonstrating antibody to Crimean-Congo haemorrhagic fever virus were compared on serum samples taken from 101 patients during the acute stage of illness and at intervals for up to 59 months thereafter, with emphasis on early detection of the immune response. The deaths of 23 patients on days 5-14 of illness were ascribed to the effects of the disease; two patients died later from other causes. Very few of the patients who died from the acute illness mounted an antibody response detectable by the methods tested. Four patients who died and 18 who recovered were treated with immune plasma collected from recovered patients. Treated patients acquired IgG antibody from the plasma, but it was possible to discern the onset of an endogenous IgM response in those individuals who survived the disease by all of the methods tested. Indirect immunofluorescence (IF) tests detected IgM and/or IgG antibodies at the earliest on day 4 of illness in about 10% of patients who survived the disease, and by day 9 all survivors had antibodies demonstrable by IF. A biotin-streptavidin IF technique offered no advantage over the standard IF test for the early detection of IgG antibody, but demonstrated higher antibody titres and detected IgM antibody earlier in about a quarter of the patients tested. An IgM-capture enzyme-linked immunoassay (ELISA) and an IgG sandwich ELISA demonstrated higher antibody titres than did IF tests, and detected antibody responses at an earlier stage of infection than did IF tests in about one-fifth of patients, but the reverse was true in a similar proportion of instances. A competition ELISA, which detected total antibody activity, produced lower titres than did the IgM and IgG ELISAs, but yielded results which were in close agreement with the findings in IF tests. It was concluded that the IF tests were most convenient for use in making a rapid serodiagnosis of the disease.  相似文献   
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Choline is known to be important in many metabolic pathways; at this time, however, it is not considered an essential nutrient for human beings. Current evidence strongly suggests that choline is “conditionally essential,” particularly for patients receiving total parenteral nutrition (TPN). Studies in patients receiving long-term TPN have shown that low levels of plasma choline are common and can be associated with hepatic steatosis. Treatment of these patients with oral administration of choline improved plasma levels and decreased hepatic fat content; however, oral choline supplements are associated with poor compliance. More recently, investigators have evaluated intravenous administration of choline as a treatment for TPN-associated hepatic steatosis in patients with documented subnormal plasma free-choline levels. Initial results indicate that intravenous administration of choline may be an effective treatment for TPN-associated hepatic dysfunction.  相似文献   
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Invariant Visual Responses From Attentional Gain Fields   总被引:5,自引:0,他引:5  
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Objective To determine the day-to-day variation in biochemical measures of iron status in a group of elderly women with rheumatoid arthritis compared with a group of healthy elderly women.Design Venous blood samples were collected from each subject on 3 nonconsecutive days during a 2-week study period; subjects had fasted overnight. Variability in hemoglobin level, hematocrit value, serum iron concentration, total iron-binding capacity, transferrin saturation, serum ferritin concentration, and plasma transferrin receptor level was determined.Subjects Two groups of women, one with rheumatoid arthritis (n=10) and another that was apparently healthy (n=10).Statistical analyses Variance component analysis was used to estimate the biological variation (σ2day) and analytic variation (σ2rep) for each iron index. The coefficient of variation (CV) for each variance component was calculated: coefficient of biological variation = CVday, coefficient of analytic variation = CVrep, and coefficient of a single future determination = CVfd.Results The CVrep for all iron indexes was smaller than the CVday in both groups. The CVday was considerably higher for serum iron concentration and for transferrin saturation than for the other indexes in both groups (16.6% arid 16.6% in healthy subjects and 33.6% and 28.2%, respectively, in subjects with rheumatoid arthritis). The higher CVday for serum iron concentration and transferrin saturation translated into a higher CVfd for these indexes. Because of the higher variance for these two indexes, more sampling days were required for reliable estimates. CVda and CVfd for plasma transferrin receptor level were relatively low.Conclusions These findings corroborate our previous finding that variation of serum ferritin concentration in the elderly is lower than that demonstrated in younger populations. This aging effect persists in the presence of rheumatoid arthritis. Fasting appeared to improve reliability in the determinations for serum iron concentration and transferrin saturation. Variability estimates for the indexes other than serum iron concentration and transferrin saturation were not altered by the inflammation of rheumatoid arthritis. Plasma transferrin receptor level is a reliable index for assessing iron status in populations with rheumatoid arthritis. J Am Diet Assoc. 1996; 96:247-251.  相似文献   
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Objective To determine change in nutrient intakes, number of servings, and contributions of total fat from food groups in children who lowered their dietary fat intake.Design A research and demonstration study designed to lower plasma low-density lipoprotein cholesterol level. There were four study groups: two intervention and two control groups. All children had hypercholesterolemia except for those in one control group. Three 24-hour dietary recalls were collected on randomly assigned days over a 2-week period at baseline and 3 months after the intervention.Subjects Three hundred three 4- to 10-year old children from suburbs north of Philadelphia, Pa.Interventions One intervention involved a home-based, parent-child autotutorial program (PCAT group) with audiotaped stories and print materials for the children and their families; the other intervention involved one face-to-face counseling session with a registered dietitian (counseling group).Outcome measures Change in mean nutrient intakes compared with the Recommended Dietary Allowance (RDA); change in number of servings and mean grams of total fat contributed from 10 different food groups.Statistical analyses performed Analyses of variance and χ2 analyses.Results Children in every study group had mean intakes of all nutrients (except vitamin D) greater than 67% of the RDA 3 months after the baseline measurement. Several food groups (ie, meats, dairy products, fats/oils, and desserts) provided less total fat to the diets of children who reduced their dietary lipid intake after 3 months (ie, PCAT and counseling groups). These children also reduced the mean number of servings selected from these food groups. Within these same food groups, some children consumed fewer servings of higher fat foods and more servings of lower fat foods.Applications/conclusions Children who lowered their dietary fat intake after intervention reported both quantitative and qualitative changes in food choices from several food groups. These choices did not significantly reduce their nutrient intakes. J Am Diet Assoc. 1996; 96:865-873.  相似文献   
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In this review of the scientific literature on the relationship between vegetable and fruit consumption and risk of cancer, results from 206 human epidemiologic studies and 22 animal studies are summarized. The evidence for a protective effect of greater vegetable and fruit consumption is consistent for cancers of the stomach, esophagus, lung, oral cavity and pharynx, endometrium, pancreas, and colon. The types of vegetables or fruit that most often appear to be protective against cancer are raw vegetables, followed by allium vegetables, carrots, green vegetables, cruciferous vegetables, and tomatoes. Substances present in vegetables and fruit that may help protect against cancer, and their mechanisms, are also briefly reviewed; these include dithiolthiones, isothiocyanates, indole-3-carbinol, allium compounds, isoflavones, protease inhibitors, saponins, phytosterols, inositol hexaphosphate, vitamin C, D-limonene, lutein, folic acid, beta carotene, lycopene, selenium, vitamin E, flavonoids, and dietary fiber. Current US vegetable and fruit intake, which averages about 3.4 servings per day, is discussed, as are possible noncancer-related effects of increased vegetable and fruit consumption, including benefits against cardiovascular disease, diabetes, stroke, obesity, diverticulosis, and cataracts. Suggestions for dietitians to use in counseling persons toward increasing vegetable and fruit intake are presented. J Am Diet Assoc. 1996; 96:1027-1039.  相似文献   
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