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The interest in non-invasive brain stimulation techniques is increasing in recent years. Among these techniques, transcranial direct current stimulation (tDCS) has been the subject of great interest among researchers because of its easiness to use, low cost, benign profile of side effects and encouraging results of research in the field. This interest has generated several studies and randomized clinical trials, particularly in psychiatry. In this review, we provide a summary of the development of the technique and its mechanism of action as well as a review of the methodological aspects of randomized clinical trials in psychiatry, including studies in affective disorders, schizophrenia, obsessive compulsive disorder, child psychiatry and substance use disorder. Finally, we provide an overview of tDCS use in cognitive enhancement as well as a discussion regarding its clinical use and regulatory and ethical issues. Although many promising results regarding tDCS efficacy were described, the total number of studies is still low, highlighting the need of further studies aiming to replicate these findings in larger samples as to provide a definite picture regarding tDCS efficacy in psychiatry.  相似文献   
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We report the first case of bone marrow cell transplantation to the myocardium of a patient with heart failure due to chagas' disease. The patient is a 52-year-old man with chronic heart failure, NYHA functional class III, despite the optimized clinical therapy. The procedure consisted of aspiration of 50 mL of bone marrow through puncture of the iliac crest, followed by filtration, separation of the mononuclear cells, resuspension, and intracoronary injection. The left ventricular ejection fraction at rest, measured using radionuclide ventriculography with labeled red blood cells prior to transplantation, was 24%, and, after 30 days, it increased to 32% with no change in the medicamentous schedule. The following measurements were assessed before and 30 days after transplantation: left ventricular end diastolic diameter (82 mm and 76 mm, respectively); Minnesota living with heart failure questionaire score (55 and 06, respectively); and distance walked in the 6-minute walking test (513 m and 683 m, respectively). Our findings show that intracoronary injection of bone marrow cells may be performed, suggesting that this is a potentially safe and effective procedure in patients with due to Chagas' disease heart failure.  相似文献   
66.

PURPOSE

Bone density at implant placement site is a key factor to obtain the primary stability of the fixture, which, in turn, is a prognostic factor for osseointegration and long-term success of an implant supported rehabilitation. Recently, an implant motor with a bone density measurement probe has been introduced. The aim of the present study was to test the objectiveness of the bone densities registered by the implant motor regardless of the operator performing them.

MATERIALS AND METHODS

A total of 3704 bone density measurements, performed by means of the implant motor, were registered by 39 operators at different implant sites during routine activity. Bone density measurements were grouped according to their distribution across the jaws. Specifically, four different areas were distinguished: a pre-antral (between teeth from first right maxillary premolar to first left maxillary premolar) and a sub-antral (more distally) zone in the maxilla, and an interforaminal (between and including teeth from first left mandibular premolar to first right mandibular premolar) and a retroforaminal (more distally) zone in the lower one. A statistical comparison was performed to check the inter-operators variability of the collected data.

RESULTS

The device produced consistent and operator-independent bone density values at each tooth position, showing a reliable bone-density measurement.

CONCLUSION

The implant motor demonstrated to be a helpful tool to properly plan implant placement and loading irrespective of the operator using it.  相似文献   
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68.

OBJECTIVE:

The purpose of this study was to evaluate the effectiveness of contrast-enhanced ultrasound with a second-generation contrast agent in distinguishing between occlusion and pseudo-occlusion of the cervical internal carotid artery, comparing it with that of conventional Doppler ultrasound and the gold standard, computed tomography angiography.

METHOD:

Between June 2006 and June 2012, we screened 72 symptomatic vascular surgery outpatients at a public hospital. Among those patients, 78 cervical internal carotid arteries were previously classified as occluded by Doppler ultrasound (without contrast). The patients were examined again with Doppler ultrasound, as well as with contrast-enhanced ultrasound and computed tomography angiography. The diagnosis was based on the presence or absence of flow.

RESULTS:

Among the 78 cervical internal carotid arteries identified as occluded by Doppler ultrasound, occlusion was confirmed by computed tomography angiography in only 57 (73.1%), compared with 59 (77.5%) for which occlusion was confirmed by contrast-enhanced ultrasound (p>0.5 vs. computed tomography angiography). Comparing contrast-enhanced ultrasound with Doppler ultrasound, we found that the proportion of cervical internal carotid arteries classified as occluded was 24.4% higher when the latter was used (p<0.001).

CONCLUSIONS:

We conclude that, in making the differential diagnosis between occlusion and pseudo-occlusion of the cervical internal carotid artery, contrast-enhanced ultrasound with a second-generation contrast agent is significantly more effective than conventional Doppler ultrasound and is equally as effective as the gold standard (computed tomography angiography). Our findings suggest that contrast-enhanced ultrasound could replace computed tomography angiography in this regard.  相似文献   
69.
The development of ultrasound contrast agents with excellent tolerance and safety profiles has notably improved liver evaluation with ultrasound(US)for several applications,especially for the detection of metastases.In particular,contrast enhanced ultrasonography(CEUS)allows the display of the parenchymal microvasculature,enabling the study and visualization of the enhancement patterns of liver lesions in real time and in a continuous manner in all vascular phases,which is similar to contrast-enhanced computed tomography(CT)and contrast-enhanced magnetic resonance imaging.Clinical studies have reported that the use of a contrast agent enables the visualization of more metastases with significantly improved sensitivity and specificity compared to baseline-US.Furthermore,studies have shown that CEUS yields sensitivities comparable to CT.In this review,we describe the state of the art of CEUS for detecting colorectal liver metastases,the imaging features,the literature reports of metastases in CEUS as well as its technique,its clinical role and its potential applications.Additionally,the updated international consensus panel guidelines are reported in this review with the inherent limitations of this technique and best practice experiences.  相似文献   
70.
In December 2019, the world started to face a new pandemic situation, the severe acute respiratory syndrome‐coronavirus 2 (SARS‐CoV‐2). Although coronavirus disease (COVID‐19) clinical manifestations are mainly respiratory, major cardiac complications are being reported. Cardiac manifestations etiology seems to be multifactorial, comprising direct viral myocardial damage, hypoxia, hypotension, enhanced inflammatory status, ACE2‐receptors downregulation, drug toxicity, endogenous catecholamine adrenergic status, among others. Studies evaluating patients with COVID‐19 presenting cardiac injury markers show that it is associated with poorer outcomes, and arrhythmic events are not uncommon. Besides, drugs currently used to treat the COVID‐19 are known to prolong the QT interval and can have a proarrhythmic propensity. This review focus on COVID‐19 cardiac and arrhythmic manifestations and, in parallel, makes an appraisal of other virus epidemics as SARS‐CoV, Middle East respiratory syndrome coronavirus, and H1N1 influenza.  相似文献   
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