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81.
Discrepancies Between Perceived Dietary Changes and 4-Day Food Records in Older Adults with Diabetes
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CAROL J. LAMMI-KEEFE PhD RD ELAINE S. LICKTEIG MS RD NAMANJEET AHLUWALIA PhD N.REBECCA HALEY MD 《Journal of the American Dietetic Association》1996,96(3):247-251
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
84.
KRISTI A. STEINMETZ PhD RD JOHN D. POTTER MD PhD 《Journal of the American Dietetic Association》1996,96(10):1027-1039
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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Cellular fatty acid composition of Actinobacillus actinomycetemcomitans and Haemophilus aphrophilus. 总被引:3,自引:3,他引:3 下载免费PDF全文
S D Braunthal S C Holt A C Tanner S S Socransky 《Journal of clinical microbiology》1980,11(6):625-630
Strains of Actinobacillus actinomycetemcomitans isolated from deep pockets of patients with juvenile periodontitis were analyzed for their content of cellular fatty acids. Oral Haemophilus strains, morphologically and biochemically similar to Haemophilus aphrophilus, were also examined for their content of cellular fatty acids. The extractable lipids of the actinobacilli represented approximately 10% of the cell dry weight, with the bound lipids representing 2 to 5%. The major fatty acids consisted of myristic (C14:0) and palmitic (C16:0) acids and a C16:1 acid, possibly palmitoleic acid, accounting for 21, 35, and 31% of the total extractable fatty acids, respectively. Haemophilus strains had a similar cellular fatty acid content. 相似文献
88.
Immune complexes in early arthritis. L Detection of immune complexes before rheumatoid arthritis is definite 总被引:2,自引:1,他引:2 下载免费PDF全文
Fifty-three patients with early arthritis were studied longitudinally for up to 3 years. During this time, 24 developed sufficient features for definite rheumatoid arthritis (RA) to be diagnosed. The other (arthralgia patients) differed from the RA patients as, in the majority, C-reactive protein and ESR were normal and anti-nuclear antibodies or rheumatoid factors were rarely found. Moreover, in time their signs and symptoms improved or disappeared. Circulating immune complexes were detected in both groups of patients by the platelet aggregation test whereas complexes detected by abnormal Clq-binding activity were found mainly in the RA patients. Platelet-aggregating complexes were usually present in the first samples studied and disappeared in the arthralgia patients with recovery from their symptoms. In the RA patients, Clq-binding complexes appeared simultaneously or later than platelet-aggregating complexes but both tests were positive several months before RA could be diagnosed. These results suggest that immune complexes are one of the first immunological abnormalities to appear in patients with arthritis. Although the constituent antigen and antibody of complexes detected by either test are unknown, their possible nature is discussed. 相似文献
89.
Isolation and characterization of the outer membrane and lipopolysaccharide from Eikenella corrodens 下载免费PDF全文
The chemical composition of the outer membrane fractions (OMFs) of Eikenella corrodens strains 23834 and 470 as well as the strain 23834 lipopolysaccharide (LPS) was determined. The OMFs were obtained by Triton X-100 treatment of the heavier membrane fraction from sucrose density centrifugation of the total membrane fraction. The resulting OMFs of strains 23834 and 470, free of cytoplasmic membrane components, were found to contain 69.6 and 75.0% (wt/wt) protein, 4.8 and 9.2% lipid, 4.6 and 4.7% carbohydrate, and 2.0 and 4.6% muramic acid, respectively. By sodium dodecyl sulfate-polyacrylamide gel electrophoresis both OMFs contained one major peptide determined to be 33,500 daltons for the strain 23834 OMF, and 37,500 daltons for the strain 470 OMF. Analysis of the OMF fatty acids revealed hexadecanoic, hexadecenoic, octadecenoic, and lesser amounts of octadecanoic acids. Transmission electron microscopic examination of the OMFs revealed typical large sheets of membrane. Structures (10 nm in diameter) resembling pores were also evident. The E. corrodens LPS was found to be composed of 34.5% (wt/wt) carbohydrate and 25.0% lipid A. Only minute amounts of 2-keto-3-deoxyoctonate and heptose could be detected. Fatty acid analysis revealed primarily octadecanoic and hexadecanoic acids, with lesser amounts of octadecenoic acid. No hydroxy fatty acids were detected. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis showed the E. corrodens LPS to resemble other smooth-type LPSs. Transmission electron microscopic examination revealed a vesicle-like morphology. The E. corrodens LPS appears not to be a "classical," i.e., enteric, type of LPS. 相似文献
90.
Cigarette smoke and phagocyte function: effect of chronic exposure in vivo and acute exposure in vitro. 下载免费PDF全文
Phagocytic function was studied in mice chronically exposed to cigarette smoke, and the effects of in vitro exposure to cigarette smoke on macrophage activity were also assessed. Cultures of radiolabeled Pseudomonas aeruginosa were employed to investigate phagocyte activity in vivo and in vitro. Mice were exposed on weekdays to fresh cigarette smoke for periods up to 37 weeks and the bactericidal and clearance activity of their lungs was measured. Both pulmonary clearance and bactericidal activity was impaired. The clearance of intravenously injected bacteria from the blood of smoke-exposed mice occurred at the same rate as in control mice, but the accumulation of radiolabel by the liver was decreased. In addition, the rate of elimination of radiolabel from the liver was less than the controls. Macrophages exposed to cigarette smoke in vitro initially had a depressed phagocytic rate, but if phagocytosis over a prolonged period was measured it was eventually enhanced over the rate of control macrophages. The vapor phase of cigarette smoke could also transiently inhibit and then enhance the phagocytic activity. 相似文献