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31.

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   
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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   
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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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TCF12 mutations have been reported very recently in coronal synostosis. We report several cases of familial coronal synostosis among four families harbouring novel TCF12 mutations. We observed a broad interfamilial phenotypic spectrum with features overlapping with the Saethre–Chotzen syndrome. TCF12 molecular testing should be considered in patients with unilateral- or bilateral-coronal synostosis associated or not with syndactyly, after having excluded mutations in the TWIST1 gene and the p.Pro250Arg mutation in FGFR3.  相似文献   
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Mandibulofacial dysostosis, Guion‐Almeida type (MFDGA) is a recently delineated multiple congenital anomalies/mental retardation syndrome characterized by the association of mandibulofacial dysostosis (MFD) with external ear malformations, hearing loss, cleft palate, choanal atresia, microcephaly, intellectual disability, oesophageal atresia (OA), congenital heart defects (CHDs), and radial ray defects. MFDGA emerges as a clinically recognizable entity, long underdiagnosed due to highly variable presentations. The main differential diagnoses are CHARGE and Feingold syndromes, oculoauriculovertebral spectrum, and other MFDs. EFTUD2, located on 17q21.31, encodes a component of the major spliceosome and is disease causing in MFDGA, due to heterozygous loss‐of‐function (LoF) mutations. Here, we describe a series of 36 cases of MFDGA, including 24 previously unreported cases, and we review the literature in order to delineate the clinical spectrum ascribed to EFTUD2 LoF. MFD, external ear anomalies, and intellectual deficiency occur at a higher frequency than microcephaly. We characterize the evolution of the facial gestalt at different ages and describe novel renal and cerebral malformations. The most frequent extracranial malformation in this series is OA, followed by CHDs and skeletal abnormalities. MFDGA is probably more frequent than other syndromic MFDs such as Nager or Miller syndromes. Although the wide spectrum of malformations complicates diagnosis, characteristic facial features provide a useful handle.  相似文献   
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BackgroundSevere hearing loss is a global problem affecting particularly developing countries. There is scarcity of recent published data on the epidemiology of childhood deafness in sub-Saharan Africa.ObjectiveTo determine the etiological profile of severe childhood deafness in Cameroon.MethodsProspective cross-sectional study of patients with a severe hearing loss that started before the age of 15 years. Detailed family and medical history was obtained; careful clinical, otological and audiological examinations were performed.ResultsA total of 582 patients with a severe hearing loss were examined. Prelingual deafness accounted for 75.1% (n = 437), with a mean age at medical diagnosis of 3.3 ± 1.2 years. This late presentation may be explained by limited parental awareness of signs raising suspicion of hearing loss, poor access to health care and the absence of neonatal screening for hearing loss in Cameroon. Identified genetic causes accounted for 14.8% (n = 86), putative environmental causes for 52.6% (n = 306) and unknown causes for 32.6% (n = 190). Amongst Genetic causes, the syndromic hearing loss accounted for 13.1% (n = 12) of cases, the rest being non syndromic (n = 74). Consanguineous families accounted for 5.7% (n = 33) of the whole sample, and 15.1% (n = 13) of genetic cases. No union between deaf parents was observed.ConclusionThese data highlight the possible predominance of putative environmental causes of childhood deafness in Cameroon, and emphasize the need for improved policies for prevention of infectious diseases and for neonatal hearing screening. However, further molecular analyses and targeted CT scan investigations are required to more accurately gauge the contribution of genetics etiologies.  相似文献   
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