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41.
Tympanometric and acoustic-reflex studies in neonates 总被引:2,自引:0,他引:2
Tympanograms and acoustic reflexes for a broadband noise and for a 1000-Hz tone were measured in normal neonates. Notched tympanograms were typical of neonatal ears for a 220-Hz probe tone. A single-peaked tympanogram was most characteristic for a probe frequency of 660 Hz. Ipsilateral and contralateral acoustic reflexes were present more frequently for a 660-Hz probe tone compared to a 220-Hz probe tone, but acoustic-reflex thresholds were not significantly different between probe tones. As with adults, acoustic-reflex thresholds for the noise were significantly lower than for the tone, and ipsilateral reflex thresholds were lower than contralateral reflex thresholds. Reliability of acoustic-reflex and tympanometric measures was high. Age change from 2 to 4 days had no significant effect on tympanometric or acoustic-reflex characteristics. There was no apparent relation between tympanometric pattern and acoustic-reflex characteristics. 相似文献
42.
Thigh pain is a serious condition in childhood and should be promptly and thoroughly investigated. Twenty-five cases of thigh
pain lasting between 1 day and 7 months with mid-femoral periosteal thickening were analysed. There were 10 patients with
Ewing's sarcoma, 7 with eosinophilic granuloma, 1 with osteoid osteoma, 1 with leukaemia, 3 with osteomyelitis, 1 with myositis
and 2 with post-traumatic periosteal reaction. It was shown that patients with Ewing's sarcoma and eosinophilic granuloma
have certain patterns of X-ray changes of high diagnostic value, which allow a proper diagnosis in most cases. 相似文献
43.
The use of maggots for wound debridement has a long history and has lately gained ground in several countries. We collected prospective data to examine the current use of larva therapy (LT) in the UK. Quantitative information was collected on 70 patients treated in nine hospitals. LT is used primarily to treat leg ulcers and generally involves three applications of larvae at two to three day intervals. This method is judged effective in wound debridement and promotes the growth of granulation tissue. Wound exudate, odour, infection and pain are all reduced by the treatment. Adverse reactions are infrequent but include pain, bleeding, pyrexia and influenza-like symptoms. Prevention of hospital admission and surgery, reduced need for antibiotics and reduced hospital stay are all identified as outcomes of LT. The nurse practitioners who used LT believed it to have an important role in wound management. A randomized clinical trial, comparing LT with other debriding agents, is required for evaluation of cost effectiveness. 相似文献
44.
Rare earth filters are known to reduce radiation dose in radiological investigations. The present investigation used Er and Sm filters that were selected because of their chemical stability and ability to withstand prolonged exposure to the atmosphere. They were used in a comparison with a conventional aluminium filter in a range of paediatric radiological procedures. Introduction of the filters instead of the conventional filter, resulted in a dose reduction of up to twofold with no discernible deterioration in image quality. 相似文献
45.
A systematic review of economic analyses of low-molecular-weight heparin for the treatment of venous thromboembolism 总被引:1,自引:0,他引:1
INTRODUCTION: Public concerns about the increase in health care expenditure have prompted investigators to analyze the costs and benefits of health care interventions. We conducted a systematic review of economic analyses of venous thromboembolism treatment focusing on studies evaluating low-molecular-weight heparin. MATERIALS AND METHODS: We identified studies by a MEDLINE search and a review of bibliographies of retrieved articles. From each eligible study, we extracted data on the study characteristics, the effectiveness, and the cost of managing the venous thromboembolism with respect to treatment. We critically appraised the studies according to the framework from the Users' Guides to the Medical Literature XIII: How to Use an Article on Economic Analysis of Clinical Practice. RESULTS: Six of these eight economic analyses of venous thromboembolism treatment that met the inclusion criteria for this review showed that low-molecular-weight heparin is associated with less recurrent venous thromboembolism and is less costly than treatment with unfractionated heparin. Although discrete recurrent venous thromboembolism event rates were not included in the seventh study, these investigators concluded that the cost of low-molecular-weight heparin for the treatment of venous thromboembolism treatment was offset by the savings associated with fewer hospital admissions when low-molecular-weight heparin was used. In the eighth study, although the cost of treatment with low-molecular-weight heparin was higher than treatment with unfractionated heparin, the investigators concluded that low-molecular-weight heparin is cost-effective for inpatient management. CONCLUSIONS: Low-molecular-weight heparin treatment may confer economic advantages over unfractionated heparin therapy because it does not require anticoagulant monitoring and it facilitates outpatient therapy. 相似文献
46.
Electrophysiological evidence for a defect in the processing of temporal sound patterns in multiple sclerosis 下载免费PDF全文
Jones SJ Sprague L Vaz Pato M 《Journal of neurology, neurosurgery, and psychiatry》2002,73(5):561-567
OBJECTIVES: To assess the processing of spectrotemporal sound patterns in multiple sclerosis by using auditory evoked potentials (AEPs) to complex harmonic tones. METHODS: 22 patients with definite multiple sclerosis but mild disability and no auditory complaints were compared with 15 normal controls. Short latency AEPs were recorded using standard methods. Long latency AEPs were recorded to synthesised musical instrument tones, at onset every two seconds, at abrupt frequency changes every two seconds, and at the end of a two second period of 16/s frequency changes. The subjects were inattentive but awake, reading irrelevant material. RESULTS: Short latency AEPs were abnormal in only 4 of 22 patients, whereas long latency AEPs were abnormal to one or more stimuli in 17 of 22. No significant latency prolongation was seen in response to onset and infrequent frequency changes (P1, N1, P2) but the potentials at the end of 16/s frequency modulations, particularly the P2 peaking approximately 200 ms after the next expected change, were significantly delayed. CONCLUSION: The delayed responses appear to be a mild disorder in the processing of change in temporal sound patterns. The delay may be conceived of as extra time taken to compare the incoming sound with the contents of a temporally ordered sensory memory store (the long auditory store or echoic memory), which generates a response when the next expected frequency change fails to occur. The defect cannot be ascribed to lesions of the afferent pathways and so may be due to disseminated brain lesions visible or invisible on magnetic resonance imaging. 相似文献
47.
This article presents a general overview of maggot debridement therapy, as used in the management of chronic infected wounds. Much has been written about this treatment method, both historically and in the past decade. Current clinical practice is discussed and clinical and laboratory research are reviewed, with attention to the inherent challenges of such research. The nature of microbial and fungal bio-film formation in chronic wounds is considered, although little is yet known of the extent and characterization of this phenomenon. The prospects for the future are addressed. These include the need for globally acceptable criteria for clinical outcomes and guidelines for "best practice," together with the pressing need for appropriately structured randomized controlled studies. 相似文献
48.
Hamuro M Palmaz JC Sprague EA Fuss C Luo J 《Journal of vascular and interventional radiology : JVIR》2001,12(5):607-611
PURPOSE: To investigate the influence of topographic features in the path of migrating endothelial cells, specifically the effect of edge angle of intravascular metallic material on endothelialization. MATERIALS AND METHODS: Flat 1-cm x 1-cm 316-L pieces of stainless steel were placed on confluent monolayers of human aortic endothelial cells. The thickness of each metal piece was ground to achieve an edge angle of 35 degrees, 70 degrees, 90 degrees, or 140 degrees (n = 6 each) in relation to the endothelial surface. Migration distance and density of endothelial cell coverage on the metal pieces were measured in groups of six each under static conditions at 4, 7, and 11 days and flow conditions (16 dynes/cm(2)) at 4 days. RESULTS: Endothelial cell migration distance along the surface of the pieces with edge angles of 35 degrees was significantly greater than that with those with larger angles (P < .05) under static and flow conditions. The migration distances on the 35 degrees piece were 87.5%, 47.3%, 57.1%, and 66.1% greater than those on the 90 degrees piece at the upstream, downstream, right, and left edges, respectively. There were no significant differences in cell density among different angle groups under flow or static conditions. CONCLUSION: The edge angle of intravascular metallic material has an influence on the rate of endothelialization. A smaller edge angle facilitates endothelialization over metallic material when compared to a larger angle. These results demonstrate the importance of metallic stent profile on endothelialization rate. 相似文献
49.
Fibrinogen: structure, function, and surface interactions 总被引:3,自引:0,他引:3
Fuss C Palmaz JC Sprague EA 《Journal of vascular and interventional radiology : JVIR》2001,12(6):677-682
Fibrinogen plays a central role in the mechanism of coagulation and thrombosis and is partially involved in the development of postintervention restenosis. Because of therapeutic implications, it is convenient for the vascular interventionalist to revisit its structure, function, and relationships within the vascular environment. This review focuses on the molecular structure, mechanisms of polymerization and lysis, and fibrinogen interaction with the platelet alpha(IIb)beta(3) [corrected] integrin. It also addresses the less understood interaction of fibrinogen with artificial surfaces. Glycoprotein IIb-IIIa blockers, targeted to interfere with fibrinogen-platelet interactions, widely used in clinical practice, are discussed, and trials of new drugs are also summarized. 相似文献
50.