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991.
992.
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
993.
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
994.
995.
996.
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
997.
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
998.
999.
G Gunnlaugsson L Smedman M C da Silva M Grandien R Zetterstr?m 《Acta paediatrica Scandinavica》1989,78(1):62-66
One hundred and forty-four children aged 9-20 months living in 14 villages in a rural area of Guinea-Bissau were examined for circulating rotavirus antibodies twice in a 15-month period. An immunofluorescence technique was used. About 3/4 of the children seroconverted, independent of age on entering the study. The age-specific proportion of seropositivity increased from 4/40 (10%) at 9-11 months to 26/29 (90%) at 33-35 months of age. All the initially seropositive children retained detectable antibodies to rotavirus. The relative risk of seroconversion was 1.4 times (95% confidence interval 1.0-2.0) more common among children living in villages by the mainroad as compared to those living off the road. Contact rate is probably dependent on population density and mobility but not on age. Breast-feeding, decreasing sharply through the age interval covered by the follow-up (9-35 months), had no apparent influence on seroconversion at the ages concerned. 相似文献
1000.
G Runhaar 《Hearing research》1989,37(2):179-187
The structure of the tectorial membrane of the chick was evaluated by scanning electron microscopy (SEM), using standard techniques, and, for the first time, by studying unfixed tectorial membranes with video-enhanced light microscopy techniques (AVEC-DIC). The SEM pictures show a widely varying morphology, ranging from a fully perforated tectorial membrane to a completely closed upper boundary, with a smooth surface. Based on several indicators, it is concluded that the latter presents the more natural state. This was confirmed by the results of the AVEC-DIC technique, which show a highly homogeneous structure. In contrast to the bulk of the tectorial membrane, its lower surface shows discrete structures, especially regularly oriented fibril bundles. 相似文献