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51.
OBJECTIVE: To determine if primary care physician specialty is associated with differences in use of health services. DATA SOURCES: Automated outpatient diagnostic, utilization, and cost data on 15,223 members (35-85 years of age) of a large group model HMO. STUDY DESIGN: One-year prospective comparison of primary care provided by 245 general internists (GIMs), 60 family physicians (FPs), and 55 subspecialty internists (SIMs) with case-mix assessed during a nine-month baseline period using Ambulatory Diagnostic Groups. PRINCIPAL FINDINGS: Adjusting for demographics and case mix, patients of GIMs and FPs had similar hospitalization and ambulatory visit rates, and similar laboratory and radiology costs. Patients of FPs made fewer visits to dermatology, psychiatry, and gynecology (combined visit rate ratio: 0.86, 95% CI: 0.74-0.96). However, they made more urgent care visits (rate ratio 1.19, 95% CI: 1.07-1.23). Patients of SIMs had higher hospitalization rates than those of GIMs (rate ratio 1.33, 95% CI: 1.06-1.68), greater use of urgent care (rate ratio: 1.14, 95% CI: 1.04-1.25), and higher costs for pharmacy (cost ratio: 1.17, 95% CI: 0.93-1.18) and radiologic services (cost ratio: 1.14, 95% CI: 1.01-1.30). The hospitalization difference was due partly to the inclusion of patients with specialty-related diagnoses in panels of SIMs. Radiology and pharmacy differences persisted after excluding these patients. CONCLUSIONS: In this uniform practice environment, specialty differences in primary care practice were small. Subspecialists used slightly more resources than generalists. The broader practice style of FPs may have created access problems for their patients.  相似文献   
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To assess the risk of myocardial infarction in users of post-menopausal hormone replacement therapy who are at high risk of coronary disease because of hypertension, diabetes mellitus, or smoking, we used data from a previously published case-control study of women 45-74 years. After adjustment for age, ethnicity, and education, the odds ratio for myocardial infarction in current users of hormone replacement therapy was 0.9 (95% confidence interval (CI) = 0.5-1.6) in women with no major coronary risk factors, 0.8 (95% CI = 0.5-1.8) in women with one risk factor, and 1.1 (95% CI = 0.5-2.2) in women with two risk factors.  相似文献   
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Background: To date only eight US studies have simultaneously examined cancer incidence in relation to social class and race/ethnicity; all but one included only black and white Americans. To address gaps in knowledge we thus investigated socioeconomic gradients in cancer incidence among four mutually exclusive US racial/ethnic groups – Asian and Pacific Islander, black, Hispanic, and white – for five major cancer sites: breast, cervix, colon, lung, and prostate cancer.Methods: We generated age-adjusted cancer incidence rates stratified by socioeconomic position using: (a) geocoded cancer registry records, (b) census population counts, and (c) 1990 census block-group socioeconomic measures. Cases (n=70,899) were diagnosed between 1988 and 1992 and lived in seven counties located in California's San Francisco Bay Area.Results: Incidence rates varied as much if not more by socioeconomic position than by race/ethnicity, and for each site the magnitude – and in some cases direction – of the socioeconomic gradient differed by race/ethnicity and, where applicable, by gender. Breast cancer incidence increased with affluence only among Hispanic women. Incidence of cervical cancer increased with socioeconomic deprivation among all four racial/ethnic groups, with trends strongest among white women. Lung cancer incidence increased with socioeconomic deprivation among all but Hispanics, for whom incidence increased with affluence. Colon and prostate cancer incidence were inconsistently associated with socioeconomic position.Conclusions: These complex patterns defy easy generalization and illustrate why US cancer data should be stratified by socioeconomic position, along with race/ethnicity and gender, so as to improve cancer surveillance, research, and control.  相似文献   
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Dysphagia as the Sole Manifestation of Bilateral Strokes   总被引:2,自引:0,他引:2  
Dysphagia can be caused by a host of factors, most of which are structural or functional. However, despite extensive evaluations, a certain number of patients have unexplained dysphagia. We present an extremely unusual case whereby a patient with an acute left hemispheric cerebral vascular accident presents with dysphagia as his sole complaint and after extensive neurological, gastroenterological, and radiographic examinations is found to have cricopharyngeal dysfunction. The etiology of this defect was not at all clinically apparent and, ultimately, magnetic resonance imaging (MRI) was performed which revealed a chronic infarction of the right frontal lobe and a smaller acute infarction in the same location of the left. This case demonstrates that swallowing disorders may be the sole presentation of stroke and that, if extensive evaluations of such patients fail to yield an etiology, one must strongly consider MRI as a tool for diagnosis, even if a CT scan is negative.  相似文献   
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OBJECTIVE

To compare the effectiveness of diabetes prevention strategies addressing postpartum weight retention for women with gestational diabetes mellitus (GDM) delivered at the health system level: mailed recommendations (usual care) versus usual care plus a Diabetes Prevention Program (DPP)–derived lifestyle intervention.

RESEARCH DESIGN AND METHODS

This study was a cluster randomized controlled trial of 44 medical facilities (including 2,280 women with GDM) randomized to intervention or usual care. The intervention included mailed gestational weight gain recommendations plus 13 telephone sessions between 6 weeks and 6 months postpartum. Primary outcomes included the following: proportion meeting the postpartum goals of 1) reaching pregravid weight if pregravid BMI <25.0 kg/m2 or 2) losing 5% of pregravid weight if BMI ≥25.0 kg/m2; and pregravid to postpartum weight change.

RESULTS

On average, over the 12-month postpartum period, women in the intervention had significantly higher odds of meeting weight goals than women in usual care (odds ratio [OR] 1.28 [95% CI 1.10, 1.47]). The proportion meeting weight goals was significantly higher in the intervention than usual care at 6 weeks (25.5 vs. 22.4%; OR 1.17 [1.01, 1.36]) and 6 months (30.6 vs. 23.9%; OR 1.45 [1.14, 1.83]). Condition differences were reduced at 12 months (33.0 vs. 28.0%; OR 1.25 [0.96, 1.62]). At 6 months, women in the intervention retained significantly less weight than women in usual care (mean 0.39 kg [SD 5.5] vs. 0.95 kg [5.5]; mean condition difference −0.64 kg [95% CI −1.13, −0.14]) and had greater increases in vigorous-intensity physical activity (mean condition difference 15.4 min/week [4.9, 25.8]).

CONCLUSIONS

A DPP-derived lifestyle intervention modestly reduced postpartum weight retention and increased vigorous-intensity physical activity.  相似文献   
60.
An adherent cell line, termed TC-1, has been isolated from long-term liquid culture of murine marrow cells by repeated exposure of the adherent cells to 0.1% trypsin. This is an alkaline phosphatase-positive cell line showing variable staining with acid phosphatase and alpha-naphthyl acetate esterase. On electron microscopy, the cells have moderate amounts of rough endoplasmic reticulum and variable numbers of polyribosomes. Some cells contain large clusters of laked glycogen particles. Intermediate junctions are present between some cells. Conditioned medium from this cell line produced from 384 to 638 units of CSF-1 per milliliter by radioimmunoassay and a CSF-1-dependent synergistic activity, which stimulates giant macrophage colony formation of marrow cells in soft agar. The conditioned medium also stimulates 3H-TdR incorporation by marrow cells in liquid culture and induces secondary adherent cell lines. The growth factor(s) produced by the TC-1 stromal cell line may be important in the regulation of early stages of hematopoietic differentiation. Two subclones, TC-1-C-11 and TC-1-C-3, have been isolated from passage 25 of the TC-1 cells by a penicylinder separation technique. The TC-1-C-11 is phenotypically like the parent TC-1 line and produces macrophage growth factors. The TC-1-C-3 grows as an epithelioid monolayer with visible junctions among adjacent cells under phase contrast microscopy. This subclone produces retrovirus and is capable of providing anchorage support for hematopoietic stem cells. The TC-1 cell line and its subclones may provide models for the control of early stem cell proliferation and differentiation.  相似文献   
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