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排序方式: 共有523条查询结果,搜索用时 15 毫秒
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Service profiles of general practitioners in Europe. European GP Task Profile Study. 总被引:1,自引:0,他引:1
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BACKGROUND: General practice is the focal point of primary care. There are national differences in the structure and organization of practice, the relationship with secondary care is being redefined, and in some countries major changes are taking place. AIM: To describe and examine differences in the service profiles of general practitioners (GPs) in European countries. METHOD: Standardized questionnaires in the national languages were sent to samples of GPs in 1993. Four areas of service provision were measured: the GP's position in the first contact with selected health problems, the involvement in minor surgery and the application of medical procedures, disease management and preventive care. The importance of the gatekeeping role, remuneration system, and geographical region in Europe was examined by comparing scores in appropriate national groupings. RESULTS: Data were received from 7233 GPs in 30 countries. Most national samples were random and the average response rate was 47%. In countries where GPs have a gatekeeping role, they had a relatively stronger position as doctors of first contact. In those countries where GPs were usually self-employed, they had a stronger role in disease management and screening for blood cholesterol. In the examination of the three structural elements of health care, the most striking differences were evident in the comparison between eastern and western Europe. GPs throughout Europe had a comparatively small role in organized health education. CONCLUSION: The position of GPs is weak in eastern Europe and some Mediterranean countries, where service profiles have a limited range. General practice was more comprehensive where the doctors had a gatekeeping role. 相似文献
3.
Research into the results of resection of hilar bile duct cancer 总被引:31,自引:0,他引:31
E J Boerma 《Surgery》1990,108(3):572-580
We found mentions of 581 resections of hilar bile duct cancer in the literature to January 1989. Resection in 499 patients, reported or updated since 1980, resulted in an operative mortality of 12% and a 5-year survival rate of 13%. Resections confined to the hepatic duct confluence or extended to the quadrate lobe led to an 8% operative mortality and a 7% 5-year survival rate, although resections combined with major liver resection gave a 15% operative mortality and a 17% 5-year survival rate. Despite the best treatments available, present-day resection modalities are usually still not radical. Extension of resection in the retrohilar and hepatoduodenal direction might further improve the long-term surgical results. 相似文献
4.
Occurrence of the t(2;5)(p23;q35) in non-Hodgkin's lymphoma 总被引:9,自引:3,他引:6
Weisenburger DD; Gordon BG; Vose JM; Bast MA; Chan WC; Greiner TC; Anderson JR; Sanger WG 《Blood》1996,87(9):3860-3868
Primary CD30(Ki-1)-positive anaplastic large-cell lymphoma (ALCL) is considered by some to be a distinct clinicopathologic entity associated with the t(2;5) (p23;q35). However, the specificity of t(2;5) for ALCL has not been carefully studied. Therefore, we performed a detailed analysis of all cases of ALCL with abnormal cytogenetics results in the Nebraska Lymphoma Study Group registry, as well as all other cases of non-Hodgkin's lymphoma with t(2;5) in the registry. We found the t(2;5) in only five of 10 cases of ALCL, four of whom were young patients. However, we also found the t(2;5) in 11 other cases of nonanaplastic lymphoma, including eight children with typical peripheral T-cell lymphomas of various types. The t(2;5) was also found in three older adults with B-cell lymphomas of various types. Thus, the t(2;5) was not specific for CD30+ ALCL. However, t(2;5) may define a clinicopathologic entity in children and young adults characterized by variable morphologies with a T-cell or indeterminate phenotype, CD30-positivity, nodal disease with frequent extranodal involvement, advanced stage, and an excellent response to therapy, including bone marrow transplantation for relapsed disease. The clinical relevance of the t(2;5) in older patients requires further study. 相似文献
5.
The magnetic resonance (MR) images of six patients with thrombosis of a dural sinus were reviewed. The diagnosis had been verified by computed tomographic scans in three patients and arteriograms in two; in the sixth patient, only MR imaging was used to confirm the clinical syndrome. In all patients, high-intensity signal was seen from the thrombus within the affected dural sinus on all echoes. This persistent signal intensity allowed intravascular clot to be distinguished from normal causes of increased signal such as flow-related enhancement (entry phenomenon) and even-echo rephasing. MR imaging demonstrated the cause of the thrombosis in three patients: two were secondary to adjacent tumors, and one was secondary to unsuspected mastoiditis. Complications such as infarction were also demonstrated. Using MR imaging, one can easily and safely diagnose thrombosis of a dural sinus. MR should be the imaging method of choice in patients suspected of having thrombosis of a dural sinus. 相似文献
6.
Marjan Boerma Gregory R Burton Junru Wang Louis M Fink Robert E McGehee Martin Hauer-Jensen 《Blood coagulation & fibrinolysis》2006,17(3):173-180
Immortalized cell lines offer significant logistical advantages over primary cells when used for in-vitro studies. Immortalized cells may, however, exhibit important differences relative to their primary cell counterparts. In this study, microarrays were used to make a genome-wide comparison between primary human umbilical vein endothelial cells (HUVECs) and EA.hy926, an immortalized HUVEC cell line, in their baseline properties and in their response to inhibition of the mevalonate pathway with an inhibitor of hydroxy methylglutaryl-coenzyme A reductase (statin). HUVECs and EA.hy926 were incubated with control medium, atorvastatin, mevalonate, or a combination of atorvastatin and mevalonate for 24 h. Gene expression profiles were obtained in duplicates using Affymetrix Human Genome U133A 2.0 arrays (Santa Clara, California, USA). Probe-sets were selected according to the following criteria: a twofold or greater increase/decrease in atorvastatin-treated cells compared with untreated cells; a twofold or greater reversal of the effect of atorvastatin by combined treatment with atorvastatin and mevalonate; no significant change in gene expression in cells treated with mevalonate alone compared with untreated cells. Most genes that were expressed by untreated HUVECs, were also expressed by untreated EA.hy926 cells. EA.hy926 cells, however, constitutively expressed a large number of additional genes, many of which were related to cell cycle control and apoptosis. Atorvastatin induced differential expression (> or = twofold) of 103 genes in HUVECs (10 up, 93 down) and 466 genes in EA.hy926 cells (198 up, 268 down). Applying the above selection criteria, thrombomodulin and tissue plasminogen activator were up-regulated in both cell types, whereas, connective tissue growth factor, thrombospondin-1, and cysteine-rich angiogenic inducer 61 were down-regulated. In conclusion, EA.hy926 cells retain most of the characteristics of endothelial cells under baseline conditions as well as after treatment with atorvastatin. It is necessary, however, to carefully select and validate changes in genes that are the focus of studies when using EA.hy926 cells. While this cell line is highly useful in studies on some genes, including genes encoding molecules involved in regulating thrombohemorrhagic homeostasis, they appear to be less suited for studies focused on other genes, particularly those involved in the regulation of cell proliferation and apoptosis. 相似文献
7.
W G Boerma 《Health policy (Amsterdam, Netherlands)》1989,13(3):225-237
About two decades ago, changes in the demand for primary care in the Netherlands resulted in a need for more interprofessional collaboration. Health centres developed as a new supply of integrated care. The government was aware of the importance of this phenomenon in its policy to strengthen primary care. The encouragement of health centres was a crucial part of it. The development of this policy and the resulting growth in the number of health centres will be reviewed here. In general, this growth is lagging behind initial policy expectations, partly because of a lack of instruments to implement PHC policy. Examination of geographical distribution of health centres, however, shows a variation suggesting that local factors also affect the development of health centres. Empirical findings show that the number of newly built houses in an area and the political 'colour' of the alderman for public health play a role in the development of health centres and thus co-determine the results of a central promotion policy to a certain extent. 相似文献
8.
Limited-field-of-view radio-frequency receiver antennas provide improved near-field sensitivity for magnetic resonance imaging by decreasing the antenna volume. The Helmholtz-type surface coil, consisting of two flat rings, is an organ-encompassing antenna that takes advantage of this principle to yield an improved signal-to-noise ratio (S/N). The coil was tested in a group of 50 patients and 16 healthy volunteers. Images obtained with the Helmholtz coil demonstrated quantitatively superior S/N of 2.2-fold or greater than that of comparison body coil images, as well as qualitatively superior anatomic resolution. 相似文献
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10.
Verhoeven AA Boendermaker PM Boerma EJ Meyboom-de Jong B 《Health libraries review》1999,16(3):141-150
The aim of this study was to develop a model to evaluate the retrieval quality of search queries performed by Dutch general practitioners using the printed Index Medicus, MEDLINE on CD-ROM, and MEDLINE through GRATEFUL MED. Four search queries related to general practice were formulated for a continuing medical education course in literature searching. The selected potential relevant citations from the course instructor and the 103 course participants together served as the basic set for the three judges to evaluate for (a) relevance and (b) quality, with the latter based on journal ranking, research design and publication type. Relevant individual citations received a citation quality score from 1 (low) to 4 (high). The overall search quality was expressed in a formula, which included the individual citation quality score of the selected and missed relevant citations, and the number of selected non-relevant citations. The outcome measures were the number and quality of relevant citations and agreement between the judges. Out of 864 citations, 139 were assessed as relevant, of which 44 citations received an individual citation quality score of 1, 76 of 2, 19 of 3 and none of 4. The level of agreement between the judges was 68% for the relevant citations, and 88% for the non-relevant citations. We describe a model for the evaluation of search queries based not only on the relevance, but also on the quality of the citations retrieved. With adaptation, this model could be generalized to other professional users, and to other bibliographic sources. 相似文献