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991.
G L Klein A C Alfrey M Shike D J Sherrard 《The American journal of clinical nutrition》1991,53(2):399-402
992.
E J Mayer B W Alderman J G Regensteiner J A Marshall W L Haskell J Baxter R F Hamman 《The American journal of clinical nutrition》1991,53(4):812-820
We evaluated the consistency of three questionnaire methods of assessing work and leisure activity in the rural biethnic population of the San Luis Valley Diabetes Study. A 7-d physical activity recall (PAR), a ranking of usual activity, and a history of usual participation in vigorous activity were used. Energy expenditure (kJ.kg-1.wk-1) (EE) was estimated from PAR. Subjects were 503 adults [49% non-Hispanic white (NHW), 51% Hispanic]. Physical activity at work rather than leisure-time activity largely determined total energy expenditure. Average EE at work increased with work rank for all subjects combined [mean EE (SEE) for rank 1 (low) = 324.2 (24.4), rank 4 (high) = 874.0 (102.1)] and within sex, ethnic, and occupational subgroups. Leisure EE increased with leisure rank only for NHW men and employed women. Similar patterns were observed in comparisons of PAR data with history of vigorous activity. Further development and validation of instruments appropriate for use across population subgroups are needed. 相似文献
993.
Human immunodeficiency virus infection in disadvantaged adolescents. Findings from the US Job Corps 总被引:3,自引:0,他引:3
OBJECTIVE--To describe the human immunodeficiency virus (HIV) epidemic among socially and educationally disadvantaged young persons in the United States. DESIGN.-We analyzed demographic and geographic findings from the screening of Job Corps students for antibody to HIV. SETTING--The Job Corps is a federal training program for disadvantaged, out-of-school youth. POPULATION SCREENED--Residential students aged 16 to 21 years who entered the Job Corps from October 1987 through February 1990. MAIN OUTCOME MEASURE--Rates of observed HIV infection in entering students, stratified by demographic and geographic features. RESULTS--Of 137,209 Job Corps students screened, 488 were HIV seropositive (3.6 per 1000), a seroprevalence rate higher than that among military applicants of the same age. Overall seroprevalence was slightly higher in male (3.7 per 1000) than in female (3.2 per 1000) Job Corps students, but among those students aged 16 and 17 years, seroprevalence was higher among females (2.3 per 1000) than among males (1.5 per 1000) (P less than .05). For students aged 16 to 21 years, seroprevalence increased with year of age: 1.8 per 1000 per year for males and 0.7 per 1000 per year for females. Among those aged 21 years, HIV prevalence was 8.9 per 1000. For black and Hispanic students from large Northeastern cities, seroprevalence increased by 4.3 per 1000 per year of age and reached 24.8 per 1000 (one of 40) in students aged 21 years. However, among students from rural areas and small towns, HIV seroprevalence was disproportionately high in the Southeast. Compared with recently described US patients with the acquired immunodeficiency syndrome, HIV-infected students who entered the Job Corps were much more likely to be female. CONCLUSIONS--These findings show that disadvantaged, out-of-school adolescents are at high risk for HIV infection. The screening results identified surprisingly high seroprevalence in the southeastern United States and demonstrated a marked shift in the HIV epidemic to young women. Controlling the HIV epidemic among teenagers must include interventions that will reach adolescents early and outside of the formal educational system. 相似文献
994.
995.
Variations in length of stay and outcomes for six medical and surgical conditions in Massachusetts and California 总被引:15,自引:1,他引:14
P D Cleary S Greenfield A G Mulley S G Pauker S A Schroeder L Wexler B J McNeil 《JAMA》1991,266(1):73-79
OBJECTIVES.--To determine the extent to which interinstitutional variations in length of stay are explained by differences in patient characteristics and to determine whether patients in hospitals with shorter lengths of stay had worse outcomes. DESIGN.--We reviewed patients' medical records and surveyed patients between 3 and 12 months after hospital discharge using a questionnaire. SETTING.--Six teaching hospitals in California and Massachusetts. PATIENTS.--A cohort of 2484 selected patients who had been hospitalized for acute myocardial infarction or to rule out acute myocardial infarction, coronary artery bypass graft surgery, total hip replacement, cholecystectomy, or transurethral prostatectomy. Between 73% and 84% of the patients with each condition completed a follow-up questionnaire. OUTCOME MEASURES.--In-hospital complications, deaths, length of stay, functional status after hospital discharge, readmission, and patient satisfaction with hospital care were analyzed. RESULTS.--Significant interinstitutional differences in length of stay were noted for all conditions except rule-out acute myocardial infarction. Statistical adjustment for case-mix differences accounted for most of the interinstitutional differences in length of stay for total hip replacement but explained little of the differences in the other conditions. When we controlled statistically for other predictors, length of stay did not have a significant impact on deaths, functional status after hospital discharge, the probability of readmission, or patient satisfaction with hospital care. CONCLUSION.--More research is needed to determine the medical practices that are related to variations in lengths of stay. Routinely available outcome data may help preserve quality in the face of efforts to decrease costs by effecting more standardized practices of care. 相似文献
996.
J L Kitzmiller L A Gavin G D Gin L Jovanovic-Peterson E K Main W D Zigrang 《JAMA》1991,265(6):731-736
To test the value of intensive management of diabetes before and during early pregnancy, 84 women recruited prior to conception were compared with 110 women who were already pregnant referred at 6 to 30 weeks' gestation. All underwent daily measurement of fasting and postprandial capillary blood glucose levels. Mean blood glucose levels during embryogenesis and organogenesis were within 3.3 to 7.8 mmol/L in 50% of preconception subjects and exceeded 10 mmol/L in 6.5%. One major congenital anomaly occurred in 84 infants (1.2%) of women treated before conception compared with 12 anomalies in 110 infants (10.9%) of mothers in the postconception group. Transient symptomatic hypoglycemia occurred during embryogenesis in 60% of women in the preconception group, with a median frequency of 2.7 episodes per week, but was not associated with excess malformations. We conclude that education and intensive management for glycemic control of diabetic women before and during early pregnancy will prevent excess rates of congenital anomalies in their infants. 相似文献
997.
998.
999.
From 1974 to 1983, simple and radical nephrectomies were performed at the Chaim Sheba Medical Center (Tel Hashomer, Israel) for renal cell carcinoma. The authors reviewed 109 cases that were followed for a period ranging from 5 to 14 years. Simple nephrectomy was performed in 55 patients, and 54 patients underwent radical nephrectomy. The selection of the surgical procedure was based on the surgeon's preference and not on the basis of clinical stage, age, or sex. The surgical results and survival rates were assessed according to the pathologic stage of the tumors. Among patients with Stage I tumor, radical nephrectomy produced better survival rates at 5 and 10 years (P = 0.03); however, when the non-cancer deaths were excluded, the difference in survival was not statistically significant. For Stage I tumors the survival free of disease at 5 years was better for the radical nephrectomy group, but this difference was not statistically significant. No difference was noticed in the local recurrence rate between the two groups. Nephrectomy in patients with Stage IV disease did not alter survival regardless of the type of operation. 相似文献
1000.
Reviewing 5 recent cases, different anatomical and clinical forms of partial or complete urachal persistency are described: patent urachus, urachal cyst, urachal sinus and urachal diverticulum. The risk of late malignant evolution of this embryonic vestige justifies radical surgical removal at time of diagnosis. 相似文献