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71.
72.
NorthMed HMO is viewed by its owners as an important vehicle for integrating rural providers in northern Michigan. Through the HMO, rural providers hope to be able to contract with government programs, while retaining private-sector patients through employer contracts. For most rural providers, NorthMed HMO does not yet represent a major source of revenues. However, the HMO is about to embark on an expansion that, if successful, will increase its importance to providers and its visibility within the service area. This planned expansion is likely to place severe demands on the financial and managerial resources of the organization. Physicians. NorthMed HMO offers a model of a rural-based HMO in which physicians play a dominant role. Rural physicians in northern Michigan own Northern Physician Organization, a physician organization which, in turn, is the major stockholder in NorthMed HMO. The geographic expansion of the HMO is tied, in large part, to the geographic expansion of the membership of Northern Physician Organization. NorthMed HMO enters new communities when a significant number of physicians in those communities joins Northern Physician Organization. When physicians purchase ownership shares in the physician organization, they indirectly become part owners of the HMO. Participation in NorthMed HMOs network has offered limited benefits to rural physicians at a minimal cost. By being a participating provider in NorthMed HMO, physicians can remain available to their patients who choose the HMO as a health insurance option. NorthMed HMO has not been aggressive in attempts to influence physician practices, and physicians bear no financial risk as a result of their participation. Participating physicians are paid under a fee-for-service arrangement with no risk sharing related to hospital use. Indirectly, through Northern Physician Organization's ownership role in the HMO, physicians have the potential to gain financially from NorthMed HMOs growth if the HMO were to be sold, but this diffuse incentive is unlikely to have an impact on physicians' day-to-day behavior. The relationship between NorthMed HMO and its physicians is likely to change soon. The number of HMO patients seen by physicians will increase if the HMO succeeds in securing Medicare and Medicaid contracts, and if its new point-of-service option attracts additional private-sector enrollees. NorthMed HMO plans to contract with Northern Physician Organization on a capitated basis to serve the HMOs enrollees, an arrangement that would place financial responsibility for managing care delivery more directly on participating physicians. This is likely to result in more aggressive utilization review and quality assurance measures. In effect, rural physicians will be faced with a difficult trade-off that they have, to this point, largely avoided: They will be asked to accept financial risk and oversight of their practices in return for the assurance that their HMO can successfully compete for local patients (and their insurance dollars) against health plans that are owned and managed by entities located outside of their rural area. 相似文献
73.
R E Christianson 《American journal of epidemiology》1979,110(2):178-187
Gross placental characteristics of 7651 smokers and nonsmokers are compared in light of the previous finding that placentas of smokers are heavier for the weight of their fetuses than are those of nonsmokers. Subchorionic fibrin deposits and placental calcification are more prevalent in the placentas of smokers than in those of nonsmokers. While mean placental weights and placental weight distributions for light and heavy smokers combined do not differ from those of nonsmokers, other placental measurements do differ. Smokers have thinner, rounder placentas than nonsmokers and the distance from the edge of rupture of the membranes to the placental margin is reduced among smokers. These findings are discussed in relation to placental changes observed at high altitudes and complications of pregnancy that differ for smokers and nonsmokers. 相似文献
74.
75.
Background
BCG vaccine is considered to have immunoprophylactic potential in leprosy. However controversy exists about the extent of prophylaxis it provides. In view of this, a study was undertaken to see the evolution of disease in established cases of leprosy who were already vaccinated with BCG and to compare it with the cases of leprosy who were not vaccinated with BCG.Methods
114 newly diagnosed cases of leprosy were studied. Patients were divided into two groups-BCG vaccinated and non-vaccinated. Clinical diagnosis of leprosy was confirmed by bacteriological and histopathological studies in each case. All patients were given standard anti leprosy treatment and were evaluated monthly for a minimum period of one year.Results
All the cases were males in the age group of 20 to 50 years. 25.4% of cases had received BCG vaccine and 74.6% were not vaccinated for the same. No significant difference was observed in the incidence of different types of leprosy in vaccinated and non-vaccinated groups. 25.9% cases in non-vaccinated group developed lepra reaction as compared to 13.8% in vaccinated group. The incidence of deformities and disabilities in vaccinated group was only 10.3% as against 18.8% in non-vaccinated group. The rate of bacillary clearance appeared faster in vaccinated group.Conclusions
Although there is no significant difference in the pattern of different types of leprosy in BCG vaccinated and non-vaccinated cases, there is reduction in the incidence of reactions as well as deformities and disabilities in BCG vaccinated cases as compared to non-vaccinated cases.Key Words: BCG Vaccine, Leprosy 相似文献76.
Tu'meh SS; Tracy DA; Wynne J; Konstam MA; Kozlowski JF; Neumann AL; Holman BL 《Radiology》1982,145(2):463-466
The authors describe a simple technique for diagnosis of tricuspid regurgitation. Red blood cells were labeled in vivo with 99mTc and 22 patients were studied with ECG-gated blood-pool imaging of the liver. A single region of interest was manually drawn around the liver and a time-activity curve obtained. The per cent change in liver counts during the cardiac cycle was found to be significantly higher in the 12 patients with tricuspid regurgitation (Group I) (mean, 4.04 +/- 1.6%; range, 1.3-21.4%) compared with the 10 controls (Group II) (mean, 0.35 +/- 0.16%; range, 0.013-1.3%) (p less than 0.05). Using a 1% change in liver counts as the criterion of a positive study, all 12 cases in Group I were diagnosed correctly, but there was one false positive in Group II; thus the sensitivity was 100% and the specificity 90%. 相似文献
77.
Limb reduction malformations of the arms are well documented in the trisomy 18 syndrome. Four cases of trisomy 18 syndrome with limb reduction malformations of the legs are described and compared with the upper limb malformations. 相似文献
78.
Differential CT diagnosis of extruded nucleus pulposus 总被引:1,自引:0,他引:1
79.
The behavioral consequences of intermittent, 5 s cold-water swims (15 degrees C) or confinement were assessed 24 h after stress in a 5 min forced swim test or an instrumental swim escape test (SET). The SET was conducted with temporal and instrumental parameters similar to the shock-motivated shuttle escape test. The tests detected significantly increased immobility in the forced swim test and increased latency to escape in the SET. These results extend previous findings with intermittent swim stress and provide evidence that intermittent swim stress produces behavioral deficits similar to other stress models. This new model may be a useful tool for exploring the physiological mechanisms underlying the stress response. 相似文献
80.
Agmon Y Khandheria BK Meissner I Petterson TM O'Fallon WM Wiebers DO Christianson TJ McConnell JP Whisnant JP Seward JB Tajik AJ 《Archives of internal medicine》2004,164(16):1781-1787
BACKGROUND: An association between systemic inflammatory markers and the presence and severity of atherosclerotic plaques has not been demonstrated in a nonselected population. The purpose of this study was to examine the association of inflammatory markers with aortic atherosclerotic plaques in a sample of the general population and in a subgroup free of clinical vascular disease. METHODS: Transesophageal echocardiography was performed in 386 subjects (median age, 66 years; 53% men). We examined the association between systemic inflammatory markers and aortic atherosclerotic plaques. RESULTS: Aortic plaques were present in 267 subjects (69%). Plaques at least 4 and 6 mm thick and mobile debris were present in 114, 41, and 20 subjects, respectively. High-sensitivity C-reactive protein (hs-CRP) level was associated with the presence of aortic plaques, adjusting for age, sex, smoking status, and additional atherosclerosis risk factors. Among subjects with plaques, hs-CRP level was independently associated with plaques at least 6 mm thick; similar trends were observed for the associations of hs-CRP level with plaques at least 4 mm thick and mobile debris. In subjects with aortic plaques who were free of clinically apparent coronary artery or cerebrovascular disease, hs-CRP level was independently associated with plaques at least 6 mm thick. CONCLUSIONS: Level of hs-CRP is independently associated with the presence and severity of aortic atherosclerotic plaques. These observations establish the association of systemic inflammation with anatomically defined atherosclerosis in the general population. 相似文献