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排序方式: 共有758条查询结果,搜索用时 15 毫秒
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OBJECTIVE: The objectives of this study were (i) to develop a conceptual framework for selecting hospitals for unit cost estimates in national and international multicentre trials and (ii) to test the impact of alternative hospital selection on the cost results. DESIGN AND SETTING: Within the conceptual framework, the following considerations which can be used when selecting a sample of hospitals for unit cost estimates in multicentre trials were identified: the number of hospitals; the sampling method; and the desired level of geographical subanalysis. Results from a recently completed international multicentre trial were used to explore changes in cost results obtained by using alternative methods of selecting and stratifying hospitals for unit cost estimates. PATIENTS AND PARTICIPANTS: The study included 5041 women from 72 hospitals in 6 countries with prelabour rupture of the membranes at term. INTERVENTIONS: The women were randomly assigned to induction of labour with intravenous oxytocin, induction of labour with prostaglandin E2 gel, or expectant management for up to 4 days with labour induced if complications developed. MAIN OUTCOME MEASURES AND RESULTS: Across each of the 4 management strategies of the study, the method of selecting and stratifying hospitals resulted in a 30 to 55% difference between the lowest and highest median unit cost estimates. In some cases, the relative ranking of the least to most expensive strategy varied across methods of hospital selection. The statistical comparisons across strategies found that the method used had a substantial impact on the conclusions of the economic evaluation. CONCLUSIONS: Unit cost information should be collected from as many hospitals as possible. Multivariate hospital cost studies are needed to identify important cost drivers that will assist with hospital selection in the future. 相似文献
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A group of 99 babies born in hospital and subsequently transferred to the special care unit were examined for the presence of candidas orally. The rate of isolation rose from 6% neonatally to 53% on day 14 of life. Among infants who did not harbour the organisms when discharged from hospital, colonization rapidly took place so that 79% did so at 4 weeks of age, after which the rate fell to 50% at one year of age. The low incidence of clinical candidosis suggests that in these babies as in other groups C. albicans is normally a harmless commensal. 相似文献
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Eight cases of dermatomyositis in children admitted to Scottish hospitals between 1962 and 1972 have been reviewed. 6 of the 8 were currently in complete remission. In the other 2 cases the disease remained active in 1 and 1 had died of cardiac failure 6 years after the onset of disease. 5 had developed extensive soft tissue calcification for which 2 were treated with ethanehydroxydiphosphonate, one showing definite improvement and the other no change. All had been treated with corticosteroids and two in addition had had cytotoxic agents (methotrexate or cyclophosphamide). The overal prognosis had probably been improved by the use of corticosteroids but not by the cytotoxic drugs. Only one of the patients was incapacitated by residual contractures or calcinosis. 相似文献
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Prevalence of risk factors for cardiovascular disease in Canadians 55 to 74 years of age: results from the Canadian Heart Health Surveys, 1986-1992 总被引:1,自引:1,他引:0 下载免费PDF全文
DB Langille MR Joffres KM MacPherson P Andreou SA Kirkland DR MacLean 《Canadian Medical Association journal》1999,161(8):S3-S9
BACKGROUND: By 2016, the proportion of Canadians older than 65 years of age will increase to 16%, and there will be an increase in the absolute number of cases of cardiovascular disease in older Canadians. The Canadian Heart Health Surveys database provides information about this population upon which health policy related to cardiovascular disease can be based. This paper presents for the first time population-based data on the risk factors for cardiovascular disease in older Canadians. METHODS: Canadians from all 10 provinces participated in surveys of cardiovascular risk factors; health insurance registries were used as sampling frames. In each province, probability samples of 2200 adults 18 to 74 years old not living in institutions, on reserves or in military camps were asked to participate in interviews and to undergo testing at clinics for major risk factors for cardiovascular disease. RESULTS: A total of 2739 men (response rate 70%) and 2617 women (response rate 66%) aged 55 to 74 years participated in the survey and also provided follow-up clinical measurements at the clinic. Overall, 52% of participants were hypertensive, 26% had isolated systolic hypertension, and 30% had a total blood cholesterol level of 6.2 mmol/L or greater. Rates of current smoking were lower in women than men (17% v. 22%). Overall, 87% of men and 78% of women who were current smokers smoked at least 10 cigarettes per day. Only slightly more than half of participants exercised at least once a week for at least 15 minutes, and almost half had a body mass index of 27 or greater. In only 4% was no major risk factor for cardiovascular disease detected. INTERPRETATION: Significant numbers of older Canadians have one or more major risk factors for cardiovascular disease. Many of these risk factors are amenable to modification. 相似文献
56.
KM RAI KJ PHILIPOSE VSM P TAKKAR RR BHONDE KK MAUDAR NK PANICKER 《Medical Journal Armed Forces India》1999,55(2):119-122
Current synthetic vascular prostheses do not acquire lining of vascular endothelium in humans or dogs. Endothelial seeding of vascular grafts has been proposed as a means of reducing the thrombogenicity of these grafts. We examined feasibility of cultivating endothelial cells (EC) by tissue culture technique and their subsequent seeding onto small diameter polytetra fluoroethylene (PTFE) grafts. Twenty adult dogs underwent common carotid artery interposition with 4 mm PTFE grafts. Ten dogs received seeded and the remaining ten received unseeded grafts. Grafts were removed at 4 and 12 weeks and their gross/morphological features compared. Cumulative patency rates for seeded grafts were 70% as compared to unseeded ones 30%. Seeded grafts were completely surfaced with a mono-layer of endothelium by 4 weeks. Small graft patency appears to be related to the establishment of an endothelial surface, the development of which is clearly facilitated by seeding with autogenous endothelium.KEY WORDS: Endothelial cell seeding, Vascular grafts 相似文献
57.
Parathyroid adenomas evaluated by Tl-201/Tc-99m pertechnetate subtraction scintigraphy and high-resolution ultrasonography 总被引:2,自引:0,他引:2
Winzelberg GG; Hydovitz JD; O'Hara KR; Anderson KM; Turbiner E; Danowski TS; Lippe RD; Melada GA; Harrison AM 《Radiology》1985,155(1):231-235
Thallium-201/technetium-99m pertechnetate subtraction scintigraphy of the parathyroid glands was performed in a prospective study of 33 patients who had undergone bilateral neck exploration for elevated serum calcium and serum parathyroid hormone levels. In 31 cases, the Tl-201/Tc-99m subtraction technique yielded an overall sensitivity of 81%, specificity of 99%, and accuracy of 94% for identifying solitary parathyroid adenomas. Tl-201/Tc-99m subtraction scintigraphy correctly identified 73% of parathyroid adenomas weighing less than 499 mg, 79% of those weighing 500-1,499 mg, and 100% of adenomas weighing more than 1,500 mg. In a subgroup of 24 patients with solitary parathyroid adenomas who underwent both scintigraphy and high-resolution sonography, the sensitivity, specificity, and accuracy of both procedures were similar. 相似文献
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