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Andrew J. Bouley Holly M. Biggs Robyn A. Stoddard Anne B. Morrissey John A. Bartlett Isaac A. Afwamba Venance P. Maro Grace D. Kinabo Wilbrod Saganda Sarah Cleaveland John A. Crump 《The American journal of tropical medicine and hygiene》2012,87(6):1105-1111
Acute and convalescent serum samples were collected from febrile inpatients identified at two hospitals in Moshi, Tanzania. Confirmed brucellosis was defined as a positive blood culture or a ≥ 4-fold increase in microagglutination test titer, and probable brucellosis was defined as a single reciprocal titer ≥ 160. Among 870 participants enrolled in the study, 455 (52.3%) had paired sera available. Of these, 16 (3.5%) met criteria for confirmed brucellosis. Of 830 participants with ≥ 1 serum sample, 4 (0.5%) met criteria for probable brucellosis. Brucellosis was associated with increased median age (P = 0.024), leukopenia (odds ratio [OR] 7.8, P = 0.005), thrombocytopenia (OR 3.9, P = 0.018), and evidence of other zoonoses (OR 3.2, P = 0.026). Brucellosis was never diagnosed clinically, and although all participants with brucellosis received antibacterials or antimalarials in the hospital, no participant received standard brucellosis treatment. Brucellosis is an underdiagnosed and untreated cause of febrile disease among hospitalized adult and pediatric patients in northern Tanzania. 相似文献
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A sex difference in mental rotation ability is well established. Among the explanations offered for this difference are that males are more frequently right hemisphere specialised for spatial processing and that they receive more spatial processing experience because of the sex stereotyping of activities involving spatial ability that exists in Western societies. Several studies have shown that males do report more spatial activity experiences on the Spatial Activity Questionnaire of Newcombe, Bandura, and Taylor (1983) and that such experience does correlate with performances on tests of mental rotation. However, two prior lateralised tachistoscopic studies failed to show right hemisphere superiority for spatial task performance or that it was positively associated with better performances on the Vandenberg Mental Rotation Test. The tachistoscopic tasks used in these studies can be criticised on methodological grounds. The present study employed a new tachistoscopic task that showed that males were significantly more right hemisphere specialised (left visual-field superior) for the tachistoscopic task than females. Magnitudes of right hemisphere specialisation on the tachistoscopic task were positively and significantly related to mental rotation ability. Spatial activity experiences were also more common in males. Covariance and partial correlation analyses indicated that the sex difference in spatial ability was primarily due to sex differences in right hemisphere specialisation for mental rotation, while sex differences in spatial activity experiences were only secondarily involved. 相似文献
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Progressive supranuclear palsy (PSP) is characterized neuropathologically by neuronal loss, gliosis, and the presence of tau-immunoreactive neuronal and glial cell inclusions affecting subcortical and some cortical regions. The objectives of this study were to determine (1) the spatial patterns of the tau-immunoreactive pathology, viz., neurofibrillary tangles (NFT), oligodendroglial inclusions (GI), tufted astrocytes (TA), and Alzheimer’s disease-type neuritic plaques (NP) in PSP and (2) to investigate the spatial correlations between the histological features. Post-mortem material of cortical and subcortical regions of eight PSP cases was studied. Spatial pattern analysis was applied to the NFT, GI, TA, NP, abnormally enlarged neurons (EN), surviving neurons, and glial cells. NFT, GI, and TA were distributed either at random or in regularly distributed clusters. The EN and NP were mainly randomly distributed. Clustering of NFT and EN was more frequent in the cortex and subcortical regions, respectively. Variations in NFT density were not spatially correlated with the densities of either GI or TA, but were positively correlated with the densities of EN and surviving neurons in some regions. (1) NFT were the most widespread tau-immunoreactive pathology in PSP being distributed randomly in subcortical regions and in regular clusters in cortical regions, (2) GI and TA were more localized and exhibited a regular pattern of clustering in subcortical regions, and (3) neuronal and glial cell pathologies were not spatially correlated. 相似文献
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E Scarr J M Craig M J Cairns M S Seo J C Galati N J Beveridge A Gibbons S Juzva B Weinrich M Parkinson-Bates A P Carroll R Saffery B Dean 《Translational psychiatry》2013,3(2):e230
Many studies have shown decreased cortical muscarinic M1 receptors (CHRM1) in schizophrenia (Sz), with one study showing Sz can be separated into two populations based on a marked loss of CHRM1 (∼75%) in ∼25% of people (Def-Sz) with the disorder. To better understand the mechanism contributing to the loss of CHRM1 in Def-Sz, we measured specific markers of gene expression in the cortex of people with Sz as a whole, people differentiated into Def-Sz and people with Sz that do not have a deficit in cortical CHRM1 (Non-Def-Sz) and health controls. We now report that cortical CHRM1 gene promoter methylation and CHRM1 mRNA are decrease in Sz, Def-Sz and Non-Def-Sz but levels of the micro RNA (miR)-107, a CHRM1 targeting miR, are increased only in Def-Sz. We also report in vitro data strongly supporting the notion that miR-107 levels regulate CHRM1 expression. These data suggest there is a reversal of the expected inverse relationship between gene promoter methylation and CHRM1 mRNA in people with Sz and that a breakdown in gene promoter methylation control of CHRM1 expression is contributing to the global pathophysiology of the syndrome. In addition, our data argues that increased levels of at least one miR, miR-107, is contributing to the marked loss of cortical CHRM1 in Def-Sz and this may be a differentiating pathophysiology. These latter data continue to support the hypothesis that microRNAs (miRNA) have a role in the underlying neurobiology of Sz but argue they are differentially affected in subsets of people within that syndrome. 相似文献
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