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991.
OBJECTIVES: This study sought to determine adherence of physicians to tuberculosis (TB) screening guidelines among foreign-born persons living in the United States who were applying for permanent residency. METHODS: Medical forms of applicants from 5 geographic areas were reviewed, along with information from a national physician database on attending physicians. Applicant and corresponding physician characteristics were compared among those who were and were not correctly screened. RESULTS: Of 5739 applicants eligible for screening via tuberculin skin test, 75% were appropriately screened. Except in San Diego, where 11% of the applicants received no screening, most of the inappropriate screening resulted from the use of chest x-rays as the initial screening tool. CONCLUSIONS: Focused physician education and periodic monitoring of adherence to screening guidelines are warranted.  相似文献   
992.
993.
Symptoms, and especially those without clear underlying medical explanations, account for a large percentage of clinical encounters. Many unexplained symptoms have been organized by patients and practitioners into syndromes such as chronic fatigue syndrome, multiple chemical sensitivity, sick building syndrome, Gulf War syndrome, and the like. All these syndromes are defined solely on the basis of symptoms rather than by medical signs. Some of the above-described conditions overlap strongly with explained conditions such as asthma. The relationship of such symptoms and syndromes to environmental exposure is often sharply debated, as is the distinction between the various syndromes. This leads to problems of what type of research should be conducted and who should conduct it. It is time to develop a comprehensive research agenda to sort out nomenclature, epidemiology, and environmental causation for these conditions, moving toward comprehensive and effective public health and clinical approaches.  相似文献   
994.
Obese and diabetic patients may benefit from foodstuffs that are poorly absorbed and/or digested at a slower rate. Prowashonupana (PW) is a cultivar of barley, whose grains are enriched in beta-glucans, and thus may be less digestible than standard barley (barley cultivar (BZ) 594.35.e). To test this, both kinds of barley were grown in a chamber into which (13)CO(2) was injected. On two occasions, 10 healthy hydrogen (H(2))-producing adults consumed in random order one 35-g portion of each of the cooked, dehulled (13)C-enriched grains. CO(2) production was measured in a whole-body direct calorimeter, and H(2) and (13)CO(2) were measured in breath at baseline and intermittently for 450 min. The percentage of the (13)C dose recovered in breath was calculated. Results were compared by repeated measures analysis of variance (ANOVA). The percentage of the (13)C dose oxidized was greater after BZ than after PW consumption (P < 0.05). The area under the curve for H(2) was greater after PW (mean +/- SD, 8658 +/- 6582) than after BZ (5178 +/- 4759) intake (P < 0.05), whereas there was no difference in CO(2) production. We conclude that absorption of PW is significantly lower than that of BZ, making the modified barley appropriate for obese and diabetic patients.  相似文献   
995.
BACKGROUND: Although HIV-positive women may be less likely than women in general to receive mammography due to socioeconomic disadvantage, HIV diagnosis may increase opportunities for medical interactions which encourage mammography. METHODS: HIV-positive (2,059) and HIV-negative (569) Women's Interagency HIV Study (WIHS) participants reported ever/never history of mammography at baseline (in 1994, 1995) and, at each 6-month follow-up visit, if they had been screened since their last visit. National Health Interview Survey (NHIS) data for 1994 were used to compare WIHS participants to U.S. women. Factors independently related to mammography were determined using logistic regression for baseline data and proportional hazards for follow-up data. Results were adjusted for age. RESULTS: Among women > or =40, fewer WIHS women, regardless of HIV status, reported screening than U.S. women (67% HIV-positive, 62% HIV-negative, 79% NHIS; P < 0.0001). First-time screening while on study was associated with being HIV-positive [rate ratio (95% confidence interval) = 1.6 (1.1, 2.3)]. Factors independently associated with screening were related to health care access and usage. CONCLUSIONS: WIHS women, a disadvantaged population, reported less mammography than the general population. HIV-positive women reported more screening than HIV-negative women, possibly because of greater opportunity to interact with the health care system.  相似文献   
996.
HIV/AIDS social work was changed fundamentally by the introduction of more effective medications to combat the disease, and by the spread of HIV/AIDS beyond the gay community to intravenous drug users and their sexual partners, women, children, adolescents, and people of color. This paper describes the professional challenges HIV/AIDS social workers now face at this stage in the history of the disease as a result of improved medications, and the spread of the disease to newer groups. We describe the roles HIV/AIDS social workers will play in the next wave of the epidemic, and discuss the implications of these changing roles for social work education and training.  相似文献   
997.
998.
BACKGROUND: Choline has recently been recognized as an essential nutrient, in part based on deficiency data in long-term home total parenteral nutrition (TPN) patients. Choline, a methyl donor in the metabolism of homocysteine, is intricately related to folate status, but little is known about choline and vitamin B12 status. Long-term TPN patients are also subject to vitamin B12 deficiency. OBJECTIVE: The objective of the study was to evaluate any interaction between choline, vitamin B12, and folate in patients with severe malabsorption syndromes, requiring long-term TPN. DESIGN: Plasma free choline, serum and red blood cell (RBC) folate, serum vitamin B12 methylmalonic acid, B6, and plasma total homocysteine concentrations were assayed by standard methods. Low choline was defined as values that fall 1 to < or =3 and marked low choline concentration as >3 SD below the control mean. RESULTS: Both low choline concentrations (52% were marked low, 33% low, 14% normal) and elevated methylmalonic acid concentrations (47%) were prevalent. Choline concentration was significantly lower and RBC folate higher in patients with elevated methylmalonic acid. Total homocysteine elevations were rare (3 of 21) and mild. CONCLUSIONS: These data suggest a strong interaction between vitamin B12 and choline deficiencies and folate status in this population, which may be due in part to variations in vitamin and choline delivery by TPN. Folate adequacy may increase B12 use for homocysteine metabolism, thus limiting B12 availability for methylmaIonic acid metabolism. Choline use may also increase, and choline deficiency may worsen if choline substitutes when the vitamin B12 side of the homocysteine metabolic pathway cannot be used.  相似文献   
999.
BACKGROUND: The purpose of this study was to examine if Type 2 diabetes mellitus is a risk factor for dementia in very old age, specifically for Alzheimer's disease (AD) and vascular dementia (VaD). METHODS: We evaluated the risk of dementia in relation to Type 2 diabetes using a population-based sample of 702 individuals aged 80 years and older (mean age 83 years). A total of 187 persons received a dementia diagnosis. Thirty-one individuals had a diabetes diagnosis prior to onset of the dementia. RESULTS: Cox proportional hazard analyses, adjusted for age, gender, education, smoking habits, and circulatory diseases, indicated an elevated risk to develop VaD (relative risk = 2.54, 95% confidence interval 1.354.78) in individuals with diabetes mellitus. No association was found between diabetes and AD. CONCLUSION: Type 2 diabetes is selectively related to the different subtypes of dementia. There is no increased risk of AD but more than a twofold risk of VaD in persons with diabetes.  相似文献   
1000.
This study examined the utility of the TELE, a telephone assessment for dementia, in a sample of 269 individuals that was not selected on the basis of previous dementia diagnosis. Thus, the conditions of the study reflect the actual situation in which a screening instrument might be employed. Scores on TELE were compared to dementia diagnoses. Using the best cutoff score, sensitivity was .86 and specificity was .90. Longitudinal follow-up established that false positives primarily included those who subsequently developed dementia. Telephone screening for dementia has both clinical and research applications. One recommendation based on our experience is that longitudinal studies should include a telephone interview component for anyone who drops out of the study, to enable characterizing the cognitive status of dropouts.  相似文献   
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