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71.
Objective To develop and test a quantitative food frequency method for administration by telephone.Design A comparison study of telephone and face-to-face interviews was conducted among a representative sample of the five major ethnic groups in Oahu, Hawaii. Two interviews were administered 4 to 6 months apart by trained interviewers using identical questionnaires and color photographs of food items showing three different portion sizes. The order of the interviewing methods was randomly assigned. The questionnaire included 115 food items selected to estimate 80% or more of usual dietary intakes. Frequencies and quantities of each item consumed during the past year were obtained.Subjects/setting Subjects were recruited from the Health Surveillance Program of the Hawaii State Department of Health and consisted of 167 men and 158 women, aged 45 to 74 years, who provided a telephone number. Eighty percent of the face-to-face interviews were conducted in the subjects’ homes and 20% were conducted at the workplace or the University of Hawaii Cancer Research Center, if requested.Statistical analyses The paired t test was used to compare the mean daily intakes obtained by the telephone and face-to-face methods. Agreement was measured by the intraclass correlation coefficient (ICC), Pearson correlation coefficient, and weighted κ statistic.Results The means of energy and each nutrient were slightly higher in the first interview than the second, regardless of the interviewing method. Because of close correspondence among all 3 statistical measures of agreement, only the ICCs are reported. The ICCs ranged from .61 for protein and vitamin A to .69 for dietary cholesterol among men, and from .61 for vitamin C to .74 for saturated fat among women. Agreement was not significantly affected by age, gender, ethnicity, order of interview, or educational level.Applications Telephone interviews to obtain quantitative food frequencies are cost-efficient methods for estimating usual dietary intakes among persons in widely scattered geographic areas. Photographs of the foods in 3 portion sizes mailed in advance help the respondents estimate amounts eaten. J Am Diet Assoc. 1998;98:44-48.  相似文献   
72.
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   
73.
N-(4-Cyanophenyl)-N'-(2-carboxyethyl)urea (2), an analogue of suosan [1,N-(4-nitrophenyl)-N'-(2-carboxyethyl)urea], is a known high-potency sweetener derived from beta-alanine. Sulfonic and phosphonic acid analogues of 2 were prepared to develop structure-activity relationships through modification of the carboxylic acid region of this family of sweeteners. Neither of the carboxylic acid replacements resulted in sweet analogues. However, we found that N-(4-cyanophenyl)-N'-[(sodiosulfo)methyl]urea (7) is an antagonist of the sweet taste response. The bitter taste response to caffeine, quinine, and naringin was also antagonized. Antagonist 7 was found to inhibit the sweet taste perception of a variety of sweeteners. Antagonist 7 had no effect on the sour or salty taste response.  相似文献   
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BACKGROUND: Inhaled fluticasone propionate (FP) therapy decreases inflammation and sub-basement membrane thickness in asthmatic airways. Bronchiolitis obliterans syndrome (BOS) in lung transplant recipients (LTRs) involves progressive airway fibrosis and obliteration. Therefore, augmented immunosuppression may be of some benefit in treating BOS. In this study, we examined the effect of 3 months of treatment with high-dose inhaled FP on the concentrations of 2 fibrogenic factors, transforming growth factor (TGF)-beta(1) and beta fibrogenic growth factor (bFGF) in bronchoalveolar lavage (BAL) fluid from clinically stable LTRs. METHODS: We conducted a randomized, double-blind, placebo-controlled, parallel group study with inhaled FP (750 microg, twice/day for 3 months) in 28 LTRs (15 FP and 13 placebo). We recruited 23 healthy controls. We performed spirometry, bronchoscopy, and bronchoalveolar lavage procedures before treatment and after 3 months of treatment. We used commercially available enzyme-linked immunosorbent assay kits to measure BAL fluid TGF-beta(1) and bFGF concentrations. RESULTS: In LTRs before treatment, BAL TGF-beta(1) concentrations (but not bFGF concentrations), total cell counts, and neutrophil percentage increased compared with controls (p < 0.05). We found no significant differences between FP and placebo groups at baseline measurements. After treatment, BAL TGF-beta(1) concentrations significantly increased in the FP group (p = 0.03), but we found no difference between FP and placebo groups; BAL bFGF concentrations increased during treatment in both groups compared with controls (p < 0.05), but not significantly within either patient group (p > 0.05). We found a reverse correlation between forced expiratory volume in 1 second (FEV(1)) and BAL TGF-beta(1) concentration in the FP group (r = -0.53, p = 0.04), and between FEV(1) and BAL TGF-beta(1) concentration in the placebo group (r = -0.74, p = 0.004). Multivariable analysis indicated no significant independent effects of inhaled FP in either BAL TGF-beta(1) or bFGF concentrations. CONCLUSIONS: Bronchoalveolar fluid TGF-beta(1) concentrations increased in LTRs after transplantation and may correlate with the decrease in lung function. Inhaled FP added to conventional immunosuppression had no effect on TGF-beta(1) or bFGF production in BAL fluid.  相似文献   
76.
Many bacterial and host cells contain large amounts of polyamines that can be released at infection sites as a result of cell lysis. Consequently, the putrescine and spermidine content of gingival fluid from inflamed periodontal pockets (0.1 to 1 mM) is sharply elevated in comparison to peripheral blood. At these levels, polyamines potentiated fMet-Leu-Phe-induced Ca2+ signaling in polymorphonuclear leukocytes (PMNs) in vitro. Consistent with the essential role of Ca2+ signaling in PMN activation, secondary granule release and superoxide anion production by fMet-Leu-Phe-stimulated PMNs was enhanced in the presence of polyamines. Thus, polyamines may play a local role in modulating the antimicrobial activity of PMNs in periodontal disease.  相似文献   
77.
Male Sprague-Dawley rats and marmosets were given a single oral 25 mg/kg dose of [3-14C]coumarin and the excretion of radioactivity in the expired air, urine and faeces monitored up to 96 h. Excretion profiles were similar in both species with the bulk of the dose being excreted in the urine and faeces within 24 h. Chromatographic analysis of 0-48 h urine samples revealed similar metabolic profiles with only small amounts of unchanged coumarin and very little 7-hydroxycoumarin. Coumarin 7-hydroxylase activity was not detectable in hepatic microsomes from either species. These results demonstrate that the disposition of [3-14C]coumarin was similar in the rat and marmoset, a New World primate, and that both species, unlike man, are poor 7-hydroxylators of coumarin.  相似文献   
78.
79.
Thirty patients with Philadelphia chromosome-positive lymphoid (20 patients) or undifferentiated (ten patients) chronic myelogenous leukemia in blast crisis were treated with 0.4 mg of vincristine by continuous intravenous infusion (CIV) daily for 4 days; (doxorubicin) 12 mg/m2 of Adriamycin (Adria Laboratories, Columbus, OH) by continuous intravenous infusion daily for 4 days; and 40 mg of decadron daily on days 1 through 4, 9 through 12, and 17 through 20 (VAD). Course 2 was given starting on day 24 with the addition of cyclophosphamide 1 g/22. Overall nine patients achieved complete remission (30%) and three attained a partial remission (10%), for an overall response rate of 40%. Four patients expired during induction whereas 14 had resistant disease. Response rate was significantly higher for patients with lymphoid compared to undifferentiated morphology (55% versus 10%; P = 0.05). In lymphoid blast crisis, Calla-positive disease was associated with a higher response rate compared to Calla-negative disease (75% versus 25%; P = 0.08). Eleven patients developed infections, and seven had fever without documented infections. The median overall survival was 29 weeks. Median survival was 43 weeks for patients achieving complete remission and 20 weeks for those with resistant disease. Remission duration was 39 weeks. After primary and salvage therapy, nine patients are alive, six of them in continuous remission for 19+ to 112+ weeks. The authors conclude that VAD chemotherapy is an effective regimen with acceptable toxicity in patients with lymphoid blast crisis especially those with Calla-positive disease. Alternate induction regimens for undifferentiated disease and for maintenance therapy are currently being investigated.  相似文献   
80.
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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