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81.
A formal statistical overview of all truly randomised trials was undertaken to determine whether antithrombotic therapy is effective and safe in the early treatment of patients with acute stroke. There were 15 completed randomised controlled trials of the value of early antithrombotic treatment in patients with acute stroke. The regimes tested in acute presumed or confirmed ischaemic stroke were: heparin, 10 trials with 1047 patients: oral anticoagulants, one trial with 51 patients: antiplatelet therapy, three trials with 103 patients. Heparin was tested in one trial with 46 patients with acute haemorrhagic stroke. Outcome measures were deep venous thrombosis (confirmed by I125 scanning or venography), pulmonary embolism, death from all causes, haemorrhagic transformation of cerebral infarction, level of disability in survivors. In patients with acute ischaemic stroke, allocation to heparin was associated with a highly significant 81% (SD 8, 2p < 0.00001) reduction in deep venous thrombosis detected by I125 fibrinogen scanning or venogram. Only three trials systematically identified pulmonary emboli, which occurred in 6/106 (5.7%) allocated control vs 3/132 (2.3%) allocated heparin, a non-significant 58% reduction (SD 45.7, 2p > 0.1). There were relatively few deaths in the trials in patients with presumed ischaemic stroke: 94/485 (19.4%) among patients allocated to the control group vs 79/497 (15.9%) among patients who were allocated heparin. The observed 18% (SD 16) reduction in the odds of death was not statistically significant. The least biased estimated of the effect of treatment on haemorrhagic transformation of the cerebral infarct (HTI) comes from trials where all patients were scanned at the end of treatment, irrespective of clinical deterioration; using this analysis, haemorrhagic transformation occurred in 7/102 (6.9%) control vs 8/106 (7.5%) treated, a non-significant 12% increase (SD 56, 2p > 0.1). These data cannot exclude the possibility that heparin substantially increases the risks of HTI. No data on disability in survivors could be obtained. Early heparin treatment might be associated with substantial reductions in deep venous thrombosis (and probably also pulmonary embolism) and possibly a one fifth reduction in mortality (equivalent to the avoidance of 20-40 early deaths per thousand patients treated.) However, the data were wholly inadequate on safety, particularly on the risk of haemorrhagic transformation of the infarct and on the hazards of heparin therapy in patients with known intracerebral haemorrhage. The trials of oral anticoagulants (15 deaths among 57 patients) and antiplatelet therapy (two deaths among 103 patients) were too small to be informative. Much larger randomized trials-comparing aspirin, heparin and the combination of both drugs against control-in patients with acute ischaemic stroke are justified (and several are now planned or underway).  相似文献   
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ABSTRACT: A random-digit dialed telephone survey was conducted in a traditionally conservative southern state to determine the level of support for sexuality education in the public schools including support for specific sexuality education topics, the earliest grade level at which each topic should be taught, and the amount of instruction time required for sexuality education in the high schools. Survey data were obtained from 534 South Carolina registered voters in late January/early February 1997. Results demonstrated that most South Carolina registered voters: 1) supported sexuality education in the public schools; 2) supported instruction on a variety of sexuality education topics; 3) supported instruction at all grade levels, especially beginning in middle school; and 4) believed instruction time for sexuality education in the high schools should either remain the same or be increased. In addition, a significant increase in support for sexuality education occurred from the beginning of the survey to the end, suggesting that the instrument itself may have served as an educational tool for respondents. The characteristics of registered voters who supported sexuality education at the beginning of the survey and at the end were examined and compared. These results may assist in the development of educational and marketing strategies designed to build support for school-based sexuality education programs in South Carolina and elsewhere205-212)  相似文献   
84.
We surveyed program coordinators at 106 hospitals and health departments that participated in the National Smallpox Vaccination Program to ascertain how program-level factors affected the rate of smallpox vaccine uptake by staff. In a fully adjusted multivariate model, health departments achieved significantly higher vaccination rates than did hospitals, as did facilities that invited fewer employees to be vaccinated.  相似文献   
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Thirty-three bovine grafts were placed in 28 patients for vascular access for hemodialysis. The indications were lack of shunt sites and anticoagulation with Coumadin in patients without vessels suitable for construction of a primary arteriovenous fistula. All but one of the grafts were loops placed in the forearm. There were 20 complications associated with the 33 procedures. Three patients required replacement of the initial graft in the early postoperative period due to thrombosis. One additional patient required two graft replacements and eventual anticoagulation with Coumadin before a successful result was obtained. There have been no serious ischemic problems. Presently, there are 27 functional bovine grafts, and 68 per cent of these are currently used for vascular access for dialysis. Patient acceptance of the fistulas has been good. The loop bovine graft fistula in the arm is an excellent means for vascular access in the patient receiving hemodialysis.  相似文献   
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If skilled histopathologists disagree over the same biopsy specimen, at least one must have an incorrect interpretation. Thus, disagreement is associated with, although not the cause of, diagnostic error. The present study aimed to determine the magnitude of variation among 10 observers with a special interest in gastrointestinal histopathology. They independently interpreted the same biopsy specimens for morphological features which may discriminate between patients with Crohn's disease and ulcerative colitis and normal subjects. Thirty of 41 features had agreement measures significantly better than expected by chance (p < 0.05). The range of agreement in the 45 observer pairs over the final diagnosis was 65-76%. There was good agreement in discriminating between normal slides and those showing confirmed inflammatory bowel disease. For normal slides, however, the term nonspecific inflammation was often applied and without any consistency. In addition, true Crohn's disease slides were often and consistently thought to be ulcerative colitis. Having identified 11 important discriminatory morphological features, two multiple regression analyses were then carried out to produce a scoring system for inflammatory bowel disease. These results suggest there is considerable room for improvement in the reliability of colonic biopsy specimen interpretation and that this could probably be achieved using more exact definitions of morphological features and diseases.  相似文献   
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Renal failure is often the presenting problem with amyloidosis and it portends a generally poor prognosis. Two of 121 patients in a home dialysis program were found to have amyloidosis after they developed unusual complications, ischemic colitis and femoral neuropathy. Both ultimately died as a result of their disease. From the limited experience that is reported, it appears that renal transplantation offers a better alternative for long term therapy than hemodialysis.  相似文献   
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