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31.
Homozygous or compound heterozygous mutations in the GJC2 gene, encoding the gap junction protein connexin47 (Cx47), cause the autosomal recessive hypomyelinating Pelizaeus–Merzbacher-like disease (PMLD1, MIM# 608804). Although clinical and neuroradiological findings resemble those of the classic Pelizaeus–Merzbacher disease, PMLD patients usually show a greater level of cognitive and motor functions. Unpredictably a homozygous missense GJC2 mutation (p.Glu260Lys) was found in a patient presenting with a very severe clinical picture characterised by congenital nystagmus and severe neurological impairment. Also magnetic resonance imaging was unusually severe, showing an abnormal supra- and infratentorial white matter involvement extending to the spinal cord. The novel p.Glu260Lys (c.778G>A) mutation, occurring in a highly conserved motif (SRPTEK) of the Cx47 extracellular loop-2 domain, was predicted, by modelling analysis, to break a ‘salt bridge network'', crucial for a proper connexin–connexin interaction to form a connexon, thus hampering the correct formation of the connexon pore. The same structural analysis, extended to the previously reported missense mutations, predicted that most changes were expected to have less severe impact on protein functions, correlating with the mild PMLD1 form of the patients. Our study expands the spectrum of PMLD1 and provides evidence that the extremely severe clinical and neuroradiological PMLD1 form of our patient likely correlates with the predicted impairment of gap junction channel assembly resulting from the detrimental effect of the new p.Glu260Lys mutant allele on Cx47 protein.  相似文献   
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ObjectiveTo compare the performance, reliability, and validity of functional tests between women with and without patellofemoral pain.MethodsTwenty women with a diagnosis of patellofemoral pain between 18 and 40 years of age and 20 age-matched pain-free controls participated in the study. All participants performed a set of five function tests: sitting-rising test, sit-to-stand in 30 seconds, stair-climb test, stair descent test, and six-minute step test. To investigate reliability, participants were assessed on two different days, seven days apart, by two independent investigators blinded to the results of the other investigator. Validity was evaluated through associations with the results on the Anterior Knee Pain Scale.ResultsPerformance in the tests was worse in women with patellofemoral pain than in the control group for the sit-to-stand in 30 seconds (mean difference [MD] 3.4reps; 95%CI: 0.4, 6.4), stair-climb test (MD: 0.36 s; 95%CI: 0.1, 0.63), and six-minute step test (MD: 45reps; 95%CI: 20, 70). No differences were observed for the sitting-rising and stair descent tests. All tests in both groups showed moderate to excellent intra- and inter-rater reliability (intraclass correlation coefficients: 0.61 to 0.91 and 0.72 to 0.96, respectively). Finally, only the results on the sit-to-stand in 30 seconds test correlated with the Anterior Knee Pain Scale (r = 0.44, p = 0.047) in the patellofemoral pain group.ConclusionWomen with patellofemoral pain present lower performance on some functional tests. Functional tests are reliable in patients with patellofemoral pain, although they are not associated with the results on the Anterior Knee Pain Scale self-questionnaire.  相似文献   
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BackgroundWe searched for differences in resting-state functional connectivity (FC) between brain networks and its relationship with the microstructure of the thalamus between migraine with pure visual auras (MA), and migraine with complex neurological auras (MA+), i.e. with the addition of at least one of sensory or language symptom.Methods3T MRI data were obtained from 20 patients with MA and 15 with MA + and compared with those from 19 healthy controls (HCs). We collected resting state data among independent component networks. Diffusivity metrics of bilateral thalami were calculated and correlated with resting state ICs-Z-scores.ResultsAs compared to HCs, both patients with MA and MA + disclosed disrupted FC between the default mode network (DMN) and the right dorsal attention system (DAS). The MA + subgroup had lower microstructural metrics than both HCs and the MA subgroup, which correlated negatively with the strength of DMN connectivity. Although the microstructural metrics of MA patients did not differ from those of HCs, these patients lacked the correlation with the strength of DAS connectivity found in HCs.ConclusionsThe present findings suggest that, as far as MRI profiles are concerned, the two clinical phenotypes of migraine with aura have both common and distinct morpho-functional features of nodes in the thalamo-cortical network.  相似文献   
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BACKGROUND: Treatment of patients with suspected deep vein thrombosis (DVT) or pulmonary embolism (PE) is problematic if diagnostic imaging is not immediately available. Pretest clinical probability (PCP) and D-dimer assessment can be used to identify patients for whom empirical protective anticoagulation is indicated. To evaluate whether PCP and D-dimer assessment, together with the use of low-molecular-weight heparins (LMWHs), allow objective appraisal of DVT and PE to be deferred for up to 72 hours, patients with suspected DVT and PE were prospectively examined. METHODS: Patients identified with a high PCP or a moderate PCP with positive D-dimer test results received a protective full-dose treatment of LMWH; the remaining patients were discharged without anticoagulant administration. However, all patients were scheduled to undergo objective tests for DVT or PE within 72 hours. Standard antithrombotic therapy was administered when deferred diagnostic tests confirmed venous thromboembolism. RESULTS: In total, 409 consecutive patients with suspected DVT and 124 with suspected PE were included in this study. A total of 23.8% (95% confidence interval [CI], 20.3%-27.3%) of patients had confirmed venous thromboembolism. At the short-term follow-up (72 hours), only a single thromboembolic event (0.2%; upper 95% CI, 0.6%) had occurred, whereas at the 3-month follow-up, 5 events (1.2%; 95% CI, 0.2%-2.1%) had occurred in patients in whom diagnosis of DVT or PE had previously been ruled out. None of the patients had major bleeding events. Ninety percent of patients were treated as outpatients. CONCLUSION: Our study demonstrates that this approach allows the safe deferral of diagnostic procedures for DVT and PE for up to 72 hours.  相似文献   
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In this paper, a new strategy for highly selective and sensitive direct detection of lymphoma cells by exploiting the interaction between a peptide and its B-cell receptor, has been evaluated. In particular, an idiotype peptide, able to specifically bind the B-cell receptor of A20 cells in mice engrafted with A20 lymphoma, has been used as molecular probe. The new detection technique has been demonstrated on a planar crystalline silicon chip. Coverage of 85% of silicon surface and detection efficiency of 8.5 × 10−3 cells/μm2 were obtained. The recognition strategy promises to extend its application in studying the interaction between ligands and their cell-surface receptors.OCIS codes: (000.1430) Biology and medicine, (280.1415) Biological sensing and sensors  相似文献   
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Breast cancer is one of the most common tumors in the population worldwide. Conservative breast surgery (CBS) is one of the preferred surgical options, because both the oncologic and esthetic needs of the patient can be addressed. CBS surgical outcomes tend to be more effective with reduced chances of disease recurrence when radiotherapy (RT) treatment is considered as an adjunct treatment, either applied during surgery (IORT) and/or after (EBRT). The purpose of our study was to compare surgical outcomes between IORT and EBRT after CBS. In the past 5 years, we performed CBS in 489 patients in our clinic. Of these patients, 83 underwent adjunct treatment with IORT and 109 were treated with EBRT in accordance with our university approved clinical protocol. Surgical outcomes, early complication rates, and esthetic results were compared between these two groups of CBS patients, with a mean follow‐up time of 17 months. IORT allowed breast irradiation treatment to be performed without effecting overlying skin, thus cosmetic outcomes tended to be favorable. Esthetic postoperative results assessed with the Breast Cancer Conservation Treatment (BCCTcore) software showed that the differences between IORT and EBRT were not statistically significant (including those patients that underwent further oncoplastic techniques after EBRT). The disease recurrence rates between the two groups were not significantly different. IORT is a safe, fast, and feasible technique that provides effective and comparable CBS outcomes for patients with breast cancer.  相似文献   
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