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A type C RNA virus has been detected in the culture fluids of the SU-DHL-1 human histiocytic lymphoma cell line previously established in this laboratory. In electron micrographs, the virus closely resembled other typical mammalian type C RNA tumor viruses in size and morphology. Viral RNA-dependent DNA polymerase activity has been demonstrated in particles (densities of 1.15 and 1.22 g/ml) in the microsomal cytoplasmic fraction and in pellets of culture fluids. The enzyme is partially inhibited by antibodies to the RNA-dependent DNA polymerases of simian sarcoma virus and RD-114 virus but not by antibody to the polymerase of murine leukemia virus, suggesting some degree of relatedness to type C viruses of subhuman primate origin. Typical syncytial microplaques were induced when SU-DHL-1 cells were cocultivated with rat XC cells. Although no focus formation was noted in similarly cocultivated mouse UC1-B cell cultures, the numbers of foci induced in rat embryo fibroblasts by murine sarcoma virus were significantly increased by coinfection with the virus from SU-DHL-1 cell culture fluids. No other evidence of infectivity, inducibility, or capacity for helper rescue of defective murine sarcoma virus genomes has been detected to date in cocultivation studies with a spectrum of fibroblastic and other nonlymphoid indicator cell lines of human and other species of origin.  相似文献   
94.

Background

In order to assess the preventive effects of right atrial septal pacing on atrial fibrillation (AF) in patients with sinus node dysfunction, we conducted a prospective randomized controlled study in patients requiring atrial pacing.

Methods

The inclusion criterion was the presence of a sinus node dysfunction with or without episodes of AF. Pacing sites were randomized to either the right atrial septum or appendage. Patients with permanent AF or with atrioventricular (AV) block without sinus node dysfunction were excluded. Patients were discharged at a pacing rate of 65 beats per minute after setting of the optimal AV delay. The antiarrhythmic therapy remained unchanged until the first recurrence of AF. Sequential analyses were performed with the triangular test.

Results

Mean baseline characteristics were not different between the septum (n = 57) and the appendage (n = 67) groups. The triangular test evidenced a lack of effect of septal pacing at the last sequential analysis. The rates of AF-free survival were not different between the septum and the appendage group (65% vs 64%, P = .28).In the subgroup of patients with at least 1 episode of AF 3 months before pacing, AF-free survival was increased by atrial septal pacing (70% vs 40%, P = .018). The mean follow-up was 16 ± 13 months (range, 1-54).

Conclusions

Atrial septal pacing does not have a preventive effect on the occurrence of AF in patient requiring atrial pacing for sinus node dysfunction. Subgroup analysis suggests that atrial septal pacing may benefit patients with ≥1 episode of AF in the 3 months preceding pacing.  相似文献   
95.
European Journal of Clinical Microbiology & Infectious Diseases - During an epidemic period, we compared patients hospitalized for initial suspicion of COVID-19 but for whom an alternative...  相似文献   
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98.

Background and aims

The metabolic syndrome (MS) is an emerging complication in patients with type 1 diabetes (T1D), with no preventive or therapeutic treatment reported yet. We wanted to compare the impact of two 6-month nutritional interventions, based on a Mediterranean (MED) or a low-fat diet, on waist circumference, anthropometric and metabolic outcomes in patients with both T1D and the MS.

Methods and results

Participants were randomized into 2 intervention groups: 1) MED-diet or 2) low-fat diet. The 6-month study included 9 teaching sessions with a registered dietitian. Anthropometric (primary outcome: waist circumference), metabolic and nutritional assessments were performed at inclusion, 3 and 6-month. We used mixed effects models to assess the effects of both interventions. 28 participants were included (50.9 ± 10.3 years old) with a mean BMI of 30.7 ± 3.3 kg/m2 and a waist circumference of 105.5 ± 8.9 cm at inclusion. A trend towards a greater reduction of dietary fat intakes in the low-fat diet group was observed (P-interaction = 0.09). Waist circumference was reduced at 6-month in both groups (?3.5 cm low-fat; ?1.5 cm MED-diet) with no significant difference between groups (P-interaction = 0.43). Body mass index also significantly decreased in both groups (?0.7 kg/m2 low-fat; ?1.1 kg/m2 MED-diet; P-interaction = 0.56). No significant differences between groups were observed for other metabolic parameters.

Conclusions

This study suggests that a 6-month non-restrictive dietary intervention in patients with T1D and MS could contribute to weight management, without significant differences between interventions for anthropometric and metabolic parameters. Further studies should investigate the long-term benefits of these diets.

Clinical trial registry

NCT02821585 (https://clinicaltrials.gov/).  相似文献   
99.
Despite a wide panel of tissue‐engineering models available for vesical reconstruction, the lack of a differentiated urothelium remains their main common limitation. For the first time to our knowledge, an entirely human vesical equivalent, free of exogenous matrix, has been reconstructed using the self‐assembly method. Moreover, we tested the contribution of adipose‐derived stromal cells, an easily available source of mesenchymal cells featuring many potential advantages, by reconstructing three types of equivalent, named fibroblast vesical equivalent, adipose‐derived stromal cell vesical equivalent and hybrid vesical equivalent – the latter containing both adipose‐derived stromal cells and fibroblasts. The new substitutes have been compared and characterized for matrix composition and organization, functionality and mechanical behaviour. Although all three vesical equivalents displayed adequate collagen type I and III expression, only two of them, fibroblast vesical equivalent and hybrid vesical equivalent, sustained the development of a differentiated and functional urothelium. The presence of uroplakins Ib, II and III and the tight junction marker ZO‐1 was detected and correlated with impermeability. The mechanical resistance of these tissues was sufficient for use by surgeons. We present here in vitro tissue‐engineered vesical equivalents, built without the use of any exogenous matrix, able to sustain mechanical stress and to support the formation of a functional urothelium, i.e. able to display a barrier function similar to that of native tissue. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
100.
BACKGROUND/AIMS: Combined hepatocellular-cholangiocarcinoma (HCC-CC) show dual hepatocellular and biliary epithelial differentiation. To better understand the relations between cholangiocarcinoma (CC), HCC-CC and hepatocellular carcinoma (HCC), we screened for genetic alterations. METHODS: A series of nine CC, 15 HCC-CC and three separated HCC and CC lesions ('collision tumors') were screened for loss of heterozygosity (LOH) using 400 microsatellite markers and for p53 and beta-catenin mutations. A comparison with a previously characterized series of 137 HCC was performed. RESULTS: In six cases of CC and HCC-CC, we identified TP53 gene mutations. A CTNNB1/beta-catenin was identified in two patients presenting collision tumors, but no mutations were found in CC or in HCC-CC. A high level of chromosome instability in both CC and HCC-CC was found. Recurrent specific LOH were identified at 3p and 14q in more than 50% of the CC and the HCC-CC cases, whereas these chromosomal regions were deleted in less than 10% of the HCC cases (P<10(-5)). Minimal common regions of deletion (MCRD) were defined at 3p24-p14 and 14q24-q32, respectively. CONCLUSIONS: These results suggest that combined HCC-CC are genetically closer to CC than HCC and common carcinogenesis pathways may be altered in HCC-CC and CC.  相似文献   
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