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941.
We aim to study the therapeutic effects of HBsAg‐activated DCs and cytokine‐induced killer (CIK) cells as adoptive immunotherapy in patients with Chronic Hepatitis B (CHB). Autologous HBsAg‐activated DC–CIK cells were infused into patients with CHB to evaluate their effect on HBV‐DNA, HBsAg, ALT, etc. The viral load in the treatment group decreased significantly (P < 0.001), while that in the control group did not decrease (P > 0.05). Twenty‐one patients (63.6% efficiency) in the treatment group had a viral response (≥2 log decrease in viral load), while four patients (14.8% efficiency) from the control group had a viral response. There were significant differences in the viral responses of the two groups (the control group 63.6% versus the control group 14.8%, P < 0.001). We concluded that the immunity was enhanced after HBsAg activation in DCs and CIK cells. Reinfusion of autologous HBsAg‐activated DC–CIK cells inhibited HBV proliferation in 21 of 33 (63.6%) patients.  相似文献   
942.
Receptor‐interacting protein 2 (RIP2) is a caspase recruitment domain (CARD)‐containing serine/threonine kinase that is activated by NOD1 or NOD2 recognition of their ligands and essential for the activation of NF‐κB and mitogen‐activated protein kinase (MAPK). RIP2 has been known to play an important role in innate immune responses against certain bacterial infection. However, the role and interplay of RIP2 with TLR signalling on cytokine production in macrophages against Yersinia enterocolitica infection remains poorly understood. In the present study, we examined whether RIP2 is essential for Yersinia‐induced production of cytokines in macrophages. Our results showed that naïve RIP2‐deficient macrophages produced similar level of IL‐6, TNF‐α and IL‐10 upon Y. enterocolitica infection compared with wild‐type macrophages. However, the production of IL‐6, TNF‐α and IL‐10 by Y. enterocolitica was impaired in RIP2‐deficient macrophages after lipopolysaccharide (LPS) pretreatment, a TLR4‐tolerant condition. In addition, RIP2 inhibitors, SB203580, PP2, and gefitinib, reduced IL‐6 production in TLR4‐deficient macrophages in response to Y. enterocolitica, whereas they did not affect the cytokines production in WT cells. These results demonstrate that RIP2 may play an important role in proinflammatory cytokine production in macrophages at the absence of TLR signalling.  相似文献   
943.
The aim of this study was to establish the antioxidant status and oxidative stress in adult patients with chronic idiopathic thrombocytopenic purpura (ITP). Eighty‐four patients diagnosed with chronic ITP were studied. Fifty‐eight age‐matched healthy subjects were selected as controls. Serum nitrogen monoxide ( NO), oxidized glutathione (GSSG), malondialdehyde (MDA), total antioxidant status (TAS), total oxidant status (TOS), superoxide dismutase(SOD), hydrogen peroxide enzyme (CAT), glutathione peroxidase (GSH‐Px), glutathione (GSH) were evaluated by enzyme‐linked immunosorbent assay (ELISA). It was found that serum SOD, CAT, GSH‐Px, GSH, TAS levels were significantly lower in patients with chronic ITP than controls (all P < 0.05), while serum NO, GSSG, MDA, TOS values were significantly higher (P < 0.05). The number of platelet showed a negative correlation with NO, GSSG, MDA, TOS, respectively,while platelet number showed a positive correlation with SOD, CAT, GSH‐Px, GSH, TAS. These findings suggested that oxidants were increased and antioxidants were decreased in patients with chronic ITP, these may be prominent factors in destructing the platelet membrane. The scavenging of oxygen radical provides a theoretical basis for the treatment of ITP patients.  相似文献   
944.
945.
In 2007, two novel polyomaviruses KI and WU were uncovered in the respiratory secretions of children with acute respiratory symptoms. Seroepidemiological studies showed that infection by these viruses is widespread in the human population. Following these findings, different biological specimens and body compartments have been screened by real‐time PCR in the attempt to establish a pathogenetic role for KI polyomavirus (KIPyV) and WU polyomavirus (WUPyV) in human diseases. Although both viruses have been found mainly in respiratory tract samples of immunocompromised patients, a clear causative link with the respiratory disease has not been established. Indeed, the lack of specific clinical or radiological findings, the frequent co‐detection with other respiratory pathogens, the detection in subjects without signs or symptoms of respiratory disease, and the variability of the viral loads measured did not allow drawing a definitive conclusion. Prospective studies carried out on a large sample size including both immunocompromised and immunocompetent patients with and without respiratory symptoms are needed. Standardized quantitative real‐time PCR methods, definition of a clear clinical cutoff value, timing in the collection of respiratory samples, are also crucial to understand the pathogenic role, if any, of KIPyV and WUPyV in human pathology.  相似文献   
946.
Our aim was to determine the frequency of 12 common respiratory viruses in patients admitted to intensive care units with respiratory symptoms, evaluate the clinical characteristics and to compare the results to routine microbiological diagnostics. Throat swabs from 122 intensive care‐patients >18 years with acute respiratory symptoms were collected upon admission and analysed with multiplex real‐time polymerase chain reaction, for 12 community respiratory viruses. Blood and respiratory tract specimens were analysed for bacteria and fungi upon clinicians' request. Clinical and paraclinical data were collected. Viruses were detected in 19 (16%) of the 122 study patients. Five virus‐positive patients (26%) had possible clinically relevant bacteria or fungi co‐detected. Patients with exacerbation in COPD were associated with a viral infection (p = 0.02). Other comorbidities, clinical and paraclinical parameters, and death were independent of a viral infection or co‐detection of bacteria/fungi. In conclusion, respiratory viruses were frequently detected in the patients. The investigated clinical and paraclinical parameters were not different in viral infections compared to other agents, thus respiratory viruses likely have similar impact on the clinical course as other agents. In 25% of the virus‐positive patients, polymicrobial aetiology was identified. Comprehensive and sensitive diagnostic methods should be emphasized to enhance respiratory diagnostics.  相似文献   
947.
We previously showed that dual‐task cost (DTC) on gait speed in people with Parkinson''s disease (PD) improved after 6 weeks of the Agility Boot Camp with Cognitive Challenge (ABC‐C) exercise program. Since deficits in dual‐task gait speed are associated with freezing of gait and gray matter atrophy, here we performed preplanned secondary analyses to answer two questions: (a) Do people with PD who are freezers present similar improvements compared to nonfreezers in DTC on gait speed with ABC‐C? (b) Can cortical thickness at baseline predict responsiveness to the ABC‐C? The DTC from 39 freezers and 43 nonfreezers who completed 6 weeks of ABC‐C were analyzed. A subset of 51 participants (21 freezers and 30 nonfreezers) with high quality imaging data were used to characterize relationships between baseline cortical thickness and delta (Δ) DTC on gait speed following ABC‐C. Freezers showed larger ΔDTC on gait speed than nonfreezers with ABC‐C program (p < .05). Cortical thickness in visual and fronto‐parietal areas predicted ΔDTC on gait speed in freezers, whereas sensorimotor‐lateral thickness predicted ΔDTC on gait speed in nonfreezers (p < .05). When matched for motor severity, visual cortical thickness was a common predictor of response to exercise in all individuals, presenting the largest effect size. In conclusion, freezers improved gait automaticity even more than nonfreezers from cognitively challenging exercise. DTC on gait speed improvement was associated with larger baseline cortical thickness from different brain areas, depending on freezing status, but visual cortex thickness showed the most robust relationship with exercise‐induced improvements in DTC.  相似文献   
948.
When speech intelligibility is reduced, listeners exploit constraints posed by semantic context to facilitate comprehension. The left angular gyrus (AG) has been argued to drive this semantic predictability gain. Taking a network perspective, we ask how the connectivity within language‐specific and domain‐general networks flexibly adapts to the predictability and intelligibility of speech. During continuous functional magnetic resonance imaging (fMRI), participants repeated sentences, which varied in semantic predictability of the final word and in acoustic intelligibility. At the neural level, highly predictable sentences led to stronger activation of left‐hemispheric semantic regions including subregions of the AG (PGa, PGp) and posterior middle temporal gyrus when speech became more intelligible. The behavioural predictability gain of single participants mapped onto the same regions but was complemented by increased activity in frontal and medial regions. Effective connectivity from PGa to PGp increased for more intelligible sentences. In contrast, inhibitory influence from pre‐supplementary motor area to left insula was strongest when predictability and intelligibility of sentences were either lowest or highest. This interactive effect was negatively correlated with the behavioural predictability gain. Together, these results suggest that successful comprehension in noisy listening conditions relies on an interplay of semantic regions and concurrent inhibition of cognitive control regions when semantic cues are available.  相似文献   
949.
The present moment is not the first time that America has found itself at war with a pathogen during a time of international conflict.Between crowded barracks at home and trenches abroad,wartime conditions helped enable the spread of influenza in the fall of 1918 during World War Ⅰ such that an estimated 20%-40% of U.S.military members were infected.While the coronavirus disease 2019 (COVID-19) pandemic is unparalleled for most of today's population,it is essential to not view it as unprecedented lest the lessons of past pandemics and their effect on the American military be forgotten.This article provides a historical perspective on the effect of the most notable antecedent pandemic,the Spanish Influenza epidemic,on American forces with the goal of understanding the interrelationship of global pandemics and the military,highlighting the unique challenges of the current pandemic,and examining how the American military has fought back against pandemics both at home and abroad,both 100 years ago and today.  相似文献   
950.
Li M, Pang SYY, Song Y, Kung MHW, Ho S‐L, Sham P‐C. Whole exome sequencing identifies a novel mutation in the transglutaminase 6 gene for spinocerebellar ataxia in a Chinese family. Autosomal dominant spinocerebellar ataxias (SCA) constitute a heterogeneous group of inherited disorders. The transglutaminase 6 (TGM6) gene was recently suggested as a SCA causative gene in Chinese SCA families. In this study, two affected members of a three‐generation Chinese family with SCA characterized by progressive cerebellar ataxia and lower limb pyramidal signs were subjected to whole exome sequencing. Through bioinformatics analysis of the sequence variants in these two individuals, we identified a novel mutation in the TGM6 gene (c.1528G>C) which showed perfect co‐segregation with disease phenotype in all nine members of this family. This finding confirms that mutations in TGM6 gene represent an important cause of SCA in Chinese. This study also shows that whole exome sequencing of a small number of affected individuals, leveraged on bioinformatics analysis, can be an efficient strategy for identifying causative mutations in rare Mendelian disorders.  相似文献   
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