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991.
BACKGROUND: Carotid endarterectomy (CEA) and carotid artery stenting (CAS) are used to prevent ischaemic stroke in patients with stenosis of the internal carotid artery. Better knowledge of risk factors could improve assignment of patients to these procedures and reduce overall risk. We aimed to assess the risk of stroke or death associated with CEA and CAS in patients with different risk factors. METHODS: We analysed data from 1196 patients randomised to CAS or CEA in the Stent-Protected Angioplasty versus Carotid Endarterectomy in Symptomatic Patients (SPACE) trial. The primary outcome event was death or ipsilateral stroke (ischaemic or haemorrhagic) with symptoms that lasted more than 24 h between randomisation and 30 days after therapy. Six predefined variables were assessed as potential risk factors for this outcome: age, sex, type of qualifying event, side of intervention, degree of stenosis, and presence of high-grade contralateral stenosis or occlusion. The SPACE trial is registered at Current Controlled Trials, with the international standard randomised controlled trial number ISRCTN57874028. FINDINGS: Risk of ipsilateral stroke or death increased significantly with age in the CAS group (p=0.001) but not in the CEA group (p=0.534). Classification and regression tree analysis showed that the age that gave the greatest separation between high-risk and low-risk populations who had CAS was 68 years: the rate of primary outcome events was 2.7% (8/293) in patients who were 68 years old or younger and 10.8% (34/314) in older patients. Other variables did not differ between the CEA and CAS groups. INTERPRETATION: Of the predefined covariates, only age was significantly associated with the risk of stroke and death. The lower risk after CAS versus CEA in patients up to 68 years of age was not detectable in older patients. This finding should be interpreted with caution because of the drawbacks of post-hoc analyses.  相似文献   
992.
Optimum care of the patient with Graves ophthalmopathy (GO) is achieved through teamwork between the endocrinologist and ophthalmologist, with input from ancillary specialists as needed. Clinical evaluation should include determination of both the severity and the activity of the disease. It is important to assess early in the evaluation the impact of the disease on the patient's quality of life and their priorities and expectations regarding management. Once this information has been gathered, careful discussion between patient and physicians can define the management plan. This article reviews the pathophysiology, epidemiology, evaluation, and management of GO.  相似文献   
993.
Primate electrophysiological and lesion studies indicate a prominent role of the left dorsal premotor cortex (PMd) in action selection based on learned sensorimotor associations. Here we applied transcranial magnetic stimulation (TMS) to human left PMd at low or high intensity while right-handed individuals performed externally paced sequential key presses with their left hand. Movements were cued by abstract visual stimuli, and subjects either freely selected a key press or responded according to a prelearned visuomotor mapping rule. Continuous arterial spin labeling was interleaved with TMS to directly assess how stimulation of left PMd modulates task-related brain activity depending on the mode of movement selection. Relative to passive viewing, both tasks activated a frontoparietal motor network. Compared with low-intensity TMS, high-intensity TMS of left PMd was associated with an increase in activity in medial and right premotor areas without affecting task performance. Critically, this increase in task-related activity was only present when movement selection relied on arbitrary visuomotor associations but not during freely selected movements. Psychophysiological interaction analysis revealed a context-specific increase in functional coupling between the stimulated left PMd and remote right-hemispheric and mesial motor regions that was only present during arbitrary visuomotor mapping. Our TMS perturbation approach yielded causal evidence that the left PMd is implicated in mapping external cues onto the appropriate movement in humans. Furthermore, the data suggest that the left PMd may transiently form a functional network together with right-hemispheric and mesial motor regions to sustain visuomotor mapping performed with the left nondominant hand.  相似文献   
994.
Selecting visual information from cluttered real-world scenes involves the matching of visual input to the observer's attentional set-an internal representation of objects that are relevant for current behavioral goals. When goals change, a new attentional set needs to be instantiated, requiring the suppression of the previous set to prevent distraction by objects that are no longer relevant. In the present fMRI study, we investigated how such suppression is implemented at the neural level. We measured human brain activity in response to natural scene photographs that could contain objects from (1) a currently relevant (target) category, (2) a previously but not presently relevant (distracter) category, and/or (3) a never relevant (neutral) category. Across conditions, multivoxel response patterns in object-selective cortex carried information about objects present in the scenes. However, this information strongly depended on the task relevance of the objects. As expected, information about the target category was significantly increased relative to the neutral category, indicating top-down enhancement of task-relevant information. Importantly, information about the distracter category was significantly reduced relative to the neutral category, indicating that the processing of previously relevant objects was suppressed. Such active suppression at the level of high-order visual cortex may serve to prevent the erroneous selection of, or interference from, objects that are no longer relevant to ongoing behavior. We conclude that the enhancement of relevant information and the suppression of distracting information both contribute to the efficient selection of visual information from cluttered real-world scenes.  相似文献   
995.
The burden of skin disease is a crucial indicator of the impact of skin disease in the general population. Despite many documented attempts in the literature to quantify independent parameters of skin disease burden, strides towards more comprehensive estimations have mainly arisen in the last decade. Utilizing the World Health Organization breakdown of disease burden, the literature was surveyed and summarized in respect to the classification, epidemiology, quality of life, and costs associated with skin disease.  相似文献   
996.
Plasminogen activator inhibitor 1 (PAI-1) is the main inhibitor of tissue-type and urokinase-type plasminogen activator. A 4G/5G polymorphism in the promoter region of the PAI-1 gene has been reported to enhance the plasma levels of PAI-1. In particular, the 4G allele (guanosine deletion) has been linked with increased plasma PAI-1 levels, which may lead to impaired activity of the fibrinolytic system, thus increasing the incidence of thrombotic events. The aim of this case-control study was to analyze whether variants of the PAI-1 promotor genotype 4G/4G, 4G/5G and 5G/5G, in particular the 4G/5G-variant, constitute an independent risk factor of cerebral venous thrombosis (CVT). A total of 136 consecutive patients with proven CVT were compared to 1,054 DNA specimens of healthy controls from a population-based cohort. PAI-1 promotor polymorphisms were evaluated using polymerase chain reaction. No significant association of CVT with PAI-1 4G/5G was found in either the additive (OR 1.04; 95?% CI 0.78–1.38) or in the dominant model (OR 1.24; 95?% CI 0.72–2.13). Also, the prevalence of the other genotypes (4G/4G and 5G/5G) in patients was not significantly different from controls. When considering the variants of the PAI-1 promoter genotype in combination with known genetical thrombophilias, no differences were found either. As was expected, the prothrombin (G20210A) genotype was confirmed as an independent risk factor for CVT. We conclude that the 4G allele of the PAI-1 polymorphism does not increase the risk of CVT in adults.  相似文献   
997.
Activation of NMDA receptor requires two co‐agonists, glutamate and glycine. Despite its intrinsic role in brain functions molecular mechanisms involved in glutamate replenishment and identification of the origin of glycine have eluded characterization. We have performed direct measurements of glycine flux by SN2 (Slc38a5; also known as SNAT5), executed extensive electrophysiological characterization as well as implemented ratiometric analyses to show that SN2 transport resembles SN1 in mechanism but differ in functional implications. We report that rat SN2 mediates electroneutral and bidirectional transport of glutamine and glycine at perisynaptic astroglial membranes. Sophisticated coupled and uncoupled movements of H+ differentially associate with glutamine and glycine transport by SN2 and regulate pHi and the release mode of the transporter. Consequently, SN2 doubles as a transmitter precursor furnisher and a potential regulator of NMDA receptors. © 2012 Wiley Periodicals, Inc.  相似文献   
998.
Over the last 10 years, significant financial support from the French National Institute of Cancer (INCa), the Ministry of Health (DGOS), and the Health and Research National Institute (Inserm) helped biobanks--of which tumour banks represent a prominent example of hospital-based infrastructures--to improve their operations, and in some instances to adopt the rules of Biological Ressource Centers as defined by OECD. Nowadays, the use of biological samples of human origin is strictly subordinated to regulations that integrate bioethical principles. However, in spite of the establishment of these regulations, requirement to obtain an authorisation and/or to register the biological collections with the Ministry of Research, many uncertainties persist. While French regulations mandate that samples can be used for research as long as patients did not oppose to such use, many biobank curators face practical and theoretical issues when establishing a Material Transfer Agreement with scientists, due to the lack of harmonization between national regulations--particularly due to a different perception of privacy and free will in anglo-american and other countries--and different demands on the side of private industry or editorial boards of scientific journals. The goal of this article is (1) to describe the procedure followed to collect patients' informed consent at the Biobank of CHU de Nice and (2) to assess the number of obtained consents in comparison to the number of collected samples between 01/09/2004 and 31/12/2009, the number of consents obtained before or after collecting the samples, and the number of patients' refusal to collect their biological resources. This balance-sheet is settled for the three major collections (thoracic, thyroid and head and neck tissues) from the Biobank of CHU de Nice. Results show that 88 % of consents were obtained during this period (82 % in a prospective manner and 6 % in a retrospective manner). Refusal was notified by writing in nine cases only. The percentage of consents varies slightly according to the collection involved and is stable from 2004 to 2009. Overall, our procedure is quite efficient at obtaining informed consents from a majority of patients for whom the tumour bank stores biological samples. This situation provides optimal conditions for the use of collected samples in the context of national and international research projects.  相似文献   
999.
The early detection of breast cancer greatly improves prognosis. One of the earliest signs of cancer is the formation of clusters of microcalcifications. We introduce a novel method for microcalcification detection based on a biologically inspired adaptive model of contrast detection. This model is used in conjunction with image filtering based on anisotropic diffusion and curvilinear structure removal using local energy and phase congruency. An important practical issue in automatic detection methods is the selection of parameters: we show that the parameter values for our algorithm can be estimated automatically from the image. This way, the method is made robust and essentially free of parameter tuning. We report results on mammograms from two databases and show that the detection performance can be improved by first including a normalisation scheme.  相似文献   
1000.
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