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BACKGROUND: The spinal administration of some N-methyl-d-aspartate receptor antagonists results in antinociception and potentiates the effects of opioids and alpha2-adrenoceptor agonists, but ketamine and its enantiomers have not been examined. The present study investigated the interactions of racemic ketamine, R(-)-ketamine and S(+)-ketamine with morphine and with dexmedetomidine. METHODS: Intrathecal catheters were implanted into male Wistar rats. Three days later, the acute nociceptive sensitivity was assessed using the tail-flick test. Analgesic latencies were converted to the percentage maximum possible effect. The dose that yielded 50% of the maximum possible effect (ED50) and dose-response and time-course curves were determined for the ketamines (30-300 microg), morphine (0.1-3.0 microg), dexmedetomidine (0.3-10.0 microg), and mixtures of two doses of ketamines (30 or 100 microg) with different doses of morphine or dexmedetomidine for fixed-dose analysis. RESULTS: Neither racemic ketamine nor its enantiomers alone had a significant effect on the tail-flick test, with the exception of the highest dose of racemic ketamine, which caused motor impairment. Morphine and dexmedetomidine each produced dose-dependent antinociception, with ED50 of 1.7 microg (95% confidence interval: 1.04-2.32) and 4. 85 microg (3.96-5.79), respectively. A low dose (30 microg) of racemic ketamine or its enantiomers did not influence the ED50 of morphine significantly. Coadministration of 100 microg racemic ketamine or S(+)-ketamine, but not R(-)-ketamine, significantly enhanced and prolonged the antinociceptive effect of morphine. Both doses of racemic ketamine or its isomers significantly decreased the ED50 value for dexmedetomidine, although the higher dose of racemic or S(+)-ketamine had the highest potency. One-hundred micrograms of racemic ketamine or S(+)-ketamine also prolonged the effects of dexmedetomidine. CONCLUSIONS: These data indicate that racemic ketamine and S(+)-ketamine, but not R(-)-ketamine, exhibit similar effectiveness in potentiating the antinociceptive effects of both morphine and dexmedetomidine. 相似文献
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Alexandra Gorea Stanescu Imre Benedek Diana Opincariu Roxana Hodas Mihaela Ratiu Theodora Benedek 《Medicine》2021,100(14)
Introduction:Multimodality assessment of coronary artery lesions has demonstrated superior effectiveness compared to the conventional approach, for assessing both anatomical and functional significance of a coronary stenosis. Multiple imaging modalities can be integrated into a fusion imaging tool to better assess myocardial ischemia.Material and methods:The FUSE-HEART trial is a single center, prospective, cohort study that will assess the impact of a coronary artery stenosis on myocardial function and viability, based on advanced fusion imaging technics derived from Cardiac Computed Tomography Angiography (CCTA). Moreover, the study will investigate the correlation between morphology and composition of the coronary plaques and myocardial ischemia in the territory irrigated by the same coronary artery. At the same time, imaging parameters will be correlated with inflammatory status of the subjects. The trial will include 100 subjects with coronary lesions found on CCTA examination. The study population will be divided into 2 groups: first group will consist of subjects with anatomically significant coronary lesions on native coronary arteries and the second one will include subjects surviving an acute myocardial infarction. The vulnerability score of the subjects will be calculated based on presence of CCTA vulnerability markers of the coronary plaques: napkin ring sign, positive remodeling, spotty calcifications, necrotic core, and low-density plaques. 3D fusion images of the coronary tree will be generated, integrating the images reflecting wall motion with the ones of coronary circulation. The fusion models will establish the correspondence between plaque composition and wall motion in the subtended myocardium of the coronary artery. The study primary outcome will be represented by the rate of major adverse cardiac events related to myocardial ischemia at 1-year post assessment, in correlation with the degree of coronary artery stenosis and myocardial ischemia or viability.The secondary outcomes are represented by the rate of re-hospitalization, rate of survival and rate of major adverse cardiovascular events (including cardiovascular death or stroke), in correlation with the morphology and composition of atheromatous plaques located in a coronary artery, and myocardial ischemia in the territory irrigated by the same coronary artery.Conclusion:In conclusion, FUSE-HEART will be a study based on modern imaging tools that will investigate the impact of a coronary artery stenosis on myocardial function and viability, using advanced fusion imaging technics derived from CCTA, sighting to validate plaque composition and morphology, together with inflammatory biomarkers, as predictors to myocardial viability. 相似文献
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The case described is of a 7-year-old boy with recurrent long-segment left ventricular outflow tract obstruction. Due to previous pulmonary artery band stenosis and subsequent repair with a prosthetic patch, the pulmonary root was not intact. In this complicated Ross-Konno operation, the prosthetic patch was replaced with autologous tissue and the repaired pulmonary root was used successfully as an autograft. 相似文献
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Heltai K Kis Z Burian K Endresz V Veres A Ludwig E Gönczöl E Valyi-Nagy I 《Atherosclerosis》2004,173(2):339-346
The relative significance of traditional risk factors, chronic infections and autoimmune processes in the development of acute myocardial infarction (AMI) has not been fully elucidated. We compared serum IgG antibody titres to various pathogens, i.e. Chlamydia pneumoniae (Cpn), cytomegalovirus (CMV) and herpes simplex virus type 1 (HSV-1), and to the potential autoantigens human heat shock protein 60 (hHSP60) and mycobacterial heat shock protein 65 (mHSP65), in serum samples obtained from patients 3-48 h after AMI (n = 40) or stable effort angina (SEA, n = 43), and from controls (n = 46). The strongest association was observed between AMI and the elevated level of hHSP60 antibodies. The association between AMI and the level of Cpn antibodies was also significant. High levels of hHSP60 and Cpn antibodies represented independent risk factors for the development of AMI, but the simultaneous presence of high levels of antibodies to Cpn and hHSP60 suggested a joint effect on the relative risk of AMI (OR = 12.0-21.1). The antibody titres to mHSP65 were higher in the SEA group than in the controls, and the simultaneous presence of high levels of Cpn and mHSP65 antibodies meant an increased risk among the SEA patients. The antibody titres to CMV or HSV-1 were similar in the three groups. In conclusion, these results demonstrate associations of AMI with high levels of anti-hHSP60 and anti-Cpn antibodies, and of SEA with the level of anti-mHSP65 antibodies, these being independent risk factors. 相似文献
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Klausz G Molnár T Nagy F Gyulai Z Boda K Lonovics J Mándi Y 《Scandinavian journal of gastroenterology》2005,40(10):1197-1204
OBJECTIVE: In Crohn's disease (CD) a Th-1 dominant immune reaction is induced, which could be associated with genetic predisposition. Several previous studies have investigated the roles of CD14, heat-shock protein (Hsp)70 and IL-10 gene polymorphisms in the development of the disease. The results are contradictory and inter-racial differences are implicated. Therefore, this phenomenon was evaluated in well-documented Caucasian patients with CD in order to verify the clinical importance of these polymorphisms. MATERIAL AND METHODS: The genomic DNA of 133 patients with CD and that of 75 healthy controls were examined. CD was divided into subgroups according to the Vienna classification. An arbitrary classification system based on disease severity was also applied, which was determined according to the therapeutic intervention. The CD14 (-159 C-->T) promoter gene polymorphism was investigated by melting-point analysis. The IL-10 (-1082 G-->A) and Hsp70-2 (1267 A-->G) gene polymorphisms were detected by RFLP (restriction fragment length polymorphism). RESULTS: None of the allele frequencies of the examined polymorphisms differed significantly between the patient and control populations. Neither the CD14 nor the IL-10 polymorphisms exhibited any correlation with the development or with the progression of the disease. With regard to Hsp70-2 gene polymorphism, those patients who carry at least one A allele have a significantly lower probability of the need for surgical intervention. CONCLUSIONS: Allele A of the Hsp70-2 gene may be associated with a less severe form of CD, suggesting the clinical value of the genotype assessment. The genetic determination of the defense mechanisms in CD appears to be associated with the polymorphism of the Hsp70-2 gene rather than that of the CD14 or IL-10 genes. 相似文献
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Krisztina Takács Eva Guillamon Mercedes Martin Pedrosa Carmen Cuadrado Carmen Burbano Mercedes Muzquiz 《Food and Agricultural Immunology》2014,25(2):173-185
Détente Instantanée Contrôlée (DIC) technology was used to reduce immunoglobulin E (IgE) reactivity of legume proteins. Soybean, roasted peanut, chickpea and lentil seeds were treated at three or six bars for 60 or 180s. The effect of this treatment on the IgE-binding pattern of the legume proteins – separated by sodium-dodecyl-sulphate polyacrylamide gel electrophoresis – was monitored by five individual paediatric legume allergic and – two individual negative control human sera. A highly cross-reactive legume positive serum was selected for the two-dimensional electrophoreses immunoblots to compare the IgE reactive protein patterns, before and after the DIC treatment. The number of the identified IgE reactive spots was highly reduced for soybean (0/7) and chickpea (2/7), and moderately reduced for lentil (4/7) when the seeds were treated at a higher pressure (6 bar) and for a longer time (180 s), but this treatment was not effective for roasted peanut (6/8) where the intensity of the IgE reactive resistant spots were even stronger. 相似文献