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Schiano P Monségu J Duriez P Broustet H Ollivier JP 《Archives des maladies du coeur et des vaisseaux》2003,96(4):295-299
Improvement of balloon and stent profile allows to use smaller-diameter catheters to avoid vascular complications by reduce the size of puncture site. First studies using 5 F guiding catheters showed good results in term of safety and feasibility. The authors performed a prospective, randomised study to define exactly the place of such small catheter compared to 6 F approach. One hundred forty eight patients were randomised, 77 in the 5 F group. The success rate per lesions was not significantly different but was less in the 5 F group (91.1 vs 96.5%). The crossover to 6 F allows good results in mainly cases. Limitations are unstable back up, worse opacification, and inability to use covered stent and to treat bifurcation lesions. There are no advantages in term of vascular complications. So, these catheters seem to be limited to treat simple lesion, allowing using the same sheath immediately after coronarography, but these results must be confirmed in a large, multicentric study. 相似文献
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The sodium-hydrogen exchanger isoform 1 (NHE-1) contributes to platelet activation at elevated pH. Effects of NHE-1 inhibitors on platelet degranulation and formation of proinflammatory and procoagulatory platelet-leukocyte aggregates (PLA) and possible interactions with P2Y(12) inhibitors--which also affect platelet degranulation--have not been investigated. Whole blood from healthy human subjects was incubated with the NHE-1 inhibitor cariporide and the P2Y(12) inhibitor AR-C 69331 MX at clinically reasonable concentrations, in the presence of normal pH or in a propionate model to activate the NHE-1 (approximately pH 7.0). The degranulation marker CD62p, the expression of the activated GPIIb/IIIa receptor (PAC-1), and formation of platelet-leukocyte (monocyte) aggregates (PLA) was assessed by flow cytometry. Cariporide at concentrations up to 20 microg/ml had no effects on ADP- (5 microM) or TRAP- (2 microM) induced CD62p expression or PLA formation at normal pH. At pH 7.0 and stimulation with ADP, PLA decreased from 64+/-24% (control) to 47+/-23% under cariporide at 2 microg/ml (p<0.05), and the MFI of PLA (i.e. the platelet mass attached at monocytes) decreased from 547+/-203 to 360+/-96 units (p<0.05). PAC-1 MFI decreased from 66+/-23 to 34+/-18 units (p<0.05) after ADP and from 74+/-29 to 42+/-17 units (p<0.05) after TRAP, respectively. AR-C 69331 MX (10 nM) had inhibitory effects on all parameters irrespectively of the pH, and the combination of both agents at pH 7.0 shows additive effects. In conclusion, our investigation points to-perhaps clinically relevant-effects of NHE-1 inhibition on the degranulation of platelets and formation of platelet-leukocyte aggregates. 相似文献
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Mohr F Hubmann W Albus M Franz U Hecht S Scherer J Binder J Sobizack N 《Psychiatry research》2003,121(1):21-30
Neurological soft signs and neuropsychological (NP) impairments are prevalent in schizophrenic patients. However, the relationship of these deficits is rarely studied, and it remains controversial in what way soft signs influence NP performance. The Neurological Evaluation Scale (NES) and a comprehensive neuropsychological test battery were used to assess soft signs and cognitive functions in 61 first-episode schizophrenic patients. The NP test battery included tests such as the California Verbal Learning Test, the Continuous Performance Test, the Span of Apprehension Test, the Stroop Color-Word Test, the Trail-Making Test and the Wisconsin Card Sorting Test. The NP tests were also administered to 87 healthy controls. The first-episode schizophrenic patients were split along the median of their NES total score (SS- vs. SS+). The level of NP performance and the differences in relative performance (shape of the NP profile) on NP functions between the two groups were assessed. The two groups (SS- vs. SS+) did not differ in any demographic or clinical variable. However, they differed in the level of their NP performance (profile mean) but did not show differential deficits in NP performance (profile shape). Neurologic soft signs influence NP performance and are correlated to a generalized NP deficit rather than to any specific NP functions. 相似文献
117.
Cardioprotective effects of the serine protease inhibitor aprotinin after regional ischemia and reperfusion on the beating heart 总被引:3,自引:0,他引:3
Pruefer D Buerke U Khalil M Dahm M Darius H Oelert H Buerke M 《The Journal of thoracic and cardiovascular surgery》2002,124(5):942-949
OBJECTIVE: Early coronary reperfusion of the ischemic myocardium is a desired therapeutic goal to preserve myocardium. However, reperfusion itself contributes to an additional myocardial injury (ie, reperfusion injury), which has been attributed to neutrophil infiltration with subsequent release of proteases and oxygen-derived radicals. We studied the effects of the serine protease inhibitor aprotinin (Trasylol) on myocardial ischemia and reperfusion in a rat model. METHODS: The effects of aprotinin (5000 and 20,000 U/kg) were examined in vivo in a rat model of regional myocardial ischemia (20 minutes) and long-term reperfusion (24 hours). Cardioprotecive effects were determined by means of measurement of creatine kinase and myeloperoxidase activity within the myocardium, as well as histochemical analysis. RESULTS: Aprotinin (20,000 U/kg) administrated 2 minutes before reperfusion significantly attenuated myocardial injury expressed as creatine kinase washout compared with that seen in vehicle-treated rats (65 +/- 25 vs 585 +/- 98 creatine kinase difference in units per 100 mg, P <.01). Administration of 5000 U/kg of the protease inhibitor resulted in partial inhibition of myocardial reperfusion injury. Moreover, cardiac myeloperoxidase activity in the ischemic myocardium, a marker of neutrophil accumulation, was significantly reduced after aprotinin treatment. Histologic analysis of the reperfused myocardium demonstrated reduced polymorphonuclear leukocyte infiltration and reduced tissue injury. Furthermore, aprotinin treatment resulted in decreased induction of cardiac myocyte apoptosis compared with that seen in vehicle-treated rats. CONCLUSIONS: Inhibition of serine proteases with aprotinin appears to be an effective means of preserving ischemic myocardium from reperfusion injury, even after 24 hours of reperfusion. Aprotinin might exert cardioprotection through inhibition of polymorphonuclear leukocyte-induced myocardial injury and inhibition of reperfusion-induced apoptosis of cardiac myocytes. 相似文献
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Wang XN Lange C Schulz U Sviland L Eissner G Oliver KM Jackson GH Holler E Dickinson AM 《Transplantation》2002,74(6):772-778
BACKGROUND: The biological properties of interleukin (IL)-10 in tolerance induction and inhibition of alloreactivity have suggested a therapeutic use of this cytokine as an additional or alternative prophylaxis for graft-versus-host disease (GvHD). However, the effects of exogenous IL-10 on GvHD are mainly studied in animal models, and the results remain conflicting. This study aims to demonstrate, for the first time, whether the addition of exogenous IL-10 can reduce the severity of graft-versus-host reactions (GvHR) in humans. METHODS: The regulatory role of exogenous IL-10 in GvHR was investigated using an in vitro human skin explant model. The effects of IL-10 on skin GvHR were tested in parallel with allo-antigen induced T-cell proliferation, cytolytic reactivity, and cytokine production. RESULTS: In the presence of IL-10, the mixed lymphocyte reaction (MLR) primed responder cells showed significantly lower proliferative and cytolytic responses compared with the responder cells from the control MLR carried out in the absence of IL-10. The responder cells from IL-10 containing MLR induced significantly less severe skin GvHR and displayed a significantly reduced T-cell activation and cytokine production. A significant correlation was observed between the levels of TNF-alpha production and the sensitivity to IL-10 modulation of GvHR. CONCLUSIONS: The addition of exogenous IL-10 strongly inhibited the broad alloreactivity initiated by primary MLR and significantly reduced the overall severity of skin GvHR induced by MLR primed responder cells. Responder cells producing high TNF-alpha following allogeneic stimulation appeared to be less sensitive to IL-10 modulation of GvHR. 相似文献
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Illmer T Schuler US Thiede C Schwarz UI Kim RB Gotthard S Freund D Schäkel U Ehninger G Schaich M 《Cancer research》2002,62(17):4955-4962
Allelic variants of the MDR-1 gene have been shown recently to influence protein expression and P-glycoprotein (P-gp) function in healthy volunteers. Therefore, 405 acute myeloid leukemia patients were investigated for somatic genotypes of the three most frequent single nucleotide polymorphisms (SNPs) in exons 12, 21, and 26. In all three loci, homozygous wild-type alleles were classified as genotype A, heterozygous as B, and homozygous mutant (alternative) allele as C. Patients with the C genotype in exons 12 and 26 showed a lower median age (both P < 0.05). Additionally, the C genotype in exons 12 and 26 was associated with cytogenetic poor risk aberrations (both P < 0.05). A possible regulatory impact of the SNPs on MDR1 mRNA expression was investigated by a Real time-PCR assay. MDR1 expression was strongly correlated with a decreased complete remission rate (P = 0.01) but failed to predict decreased overall survival (OS). There was a significant association of the A genotype in exons 21 (P = 0.05) and 26 (P < 0.05) with lower MDR1 expression, whereas the B variants showed highest MDR1 values at all three investigated gene loci. The A genotype in exon 26 was associated with lower OS (P < 0,01). In these patients, worse OS is likely attributable to an increased risk of relapse (P < 0.001). We were able to detect a linkage disequilibrium of the investigated SNPs, indicating combined polymorphisms that could affect the regulation of MDR1 expression. The A genotype of all SNPs demonstrated both lowest MDR1 values and significantly decreased OS (P < 0.05) with a high probability of relapses (P < 0.01). These observations indicate that allelic variants of the MDR1 gene may influence therapy outcome by additional mechanisms, different from P-gp expression on acute myeloid leukemia blasts, possibly involving pharmacokinetic effects of P-gp. 相似文献