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31.
Robert Ladouceur Francine Ferland Frank Vitaro 《The journal of primary prevention》2004,25(3):329-335
Research on gambling demonstrates that youths are involved in gambling activities. As they take part in these activities, young people develop and maintain irrational thoughts about gambling and become at risk for developing severe gambling problems. In a previous study, a French video was designed specifically to correct misconceptions and increase knowledge about gambling (Ferland, Ladouceur, & Vitaro, 2002). Findings indicated that the video significantly improves subjects' knowledge about gambling and corrects their misconceptions. The present study aims to evaluate the effectiveness of the English version of that video. The sample comprised 506 grade 7 and 8 English speaking students from Canada. The results confirmed the efficacy of the video in increasing knowledge of gambling and correcting misconceptions concerning the outcome of these games. The implications of these results for the prevention of gambling problems are discussed. 相似文献
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The need to consider using dapsone in pregnant women for its antimalarial activity is becoming greater in areas where Plasmodium falciparum resistance to chloroquine and pyrimethamine-sulfadoxine is rapidly increasing. Dapsone in combination with other antimalarials might provide a valuable alternative for both treatment and prophylaxis. This review assesses the clinical pharmacology of dapsone and its adverse drug reactions in relation to haemolysis, glucose-6-phosphate dehydrogenase (G6PD) deficiency, blood dyscrasias and methaemoglobinaemia. Studies are summarised reporting its use in leprosy, dermatological and other conditions, and malaria, in relation to maternal and infant outcomes. A total of 924 pregnancies were identified during which dapsone therapy was taken. Only limited data are available and this precludes a meaningful quantitative benefit-risk analysis.Mild degrees of haemolysis consistently occur with continued therapy, although adverse effects may be less likely with intermittent treatment, as most reported adverse effects have occurred with long-term use of dapsone. There are a number of gaps in knowledge where more data are needed. These include no data on pharmacokinetics in pregnancy and whether these are altered with co-administration of chlorproguanil. Potential complications in women with severe anaemia are unknown and there is no information on haemolytic effects in women or the fetus with G6PD deficiency. The use of dapsone in HIV-infected women in malarious areas could carry increased risks because of the immunosuppressive actions of the drug. Trials of dapsone therapy in pregnancy should be considered in malarious areas where there is good reason for its deployment. Controlled trials have provided data on maternal tolerance, and dapsone in combination with other antimalarial drugs can offer clear benefit in terms of improved birthweight. The use of dapsone combinations should be considered when no good alternative is available and the threat of malaria is the greater risk. 相似文献
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D. Projean P.-E. Morin T. M. Tu J. Ducharme 《Xenobiotica; the fate of foreign compounds in biological systems》2013,43(8):841-854
1. The aim was to identify the cytochrome P450 (CYP) enzymes responsible for the N -demethylation of morphine in vitro. 2. In human liver microsomes, normorphine formation followed Michaelis-Menten kinetics with mean K m and V max of 12.4 ± 2.2 mM and 1546 ± 121 pmol?min ? 1?mg ? 1, respectively. In microsomes from a panel of 14 human livers phenotyped for 10 CYP enzymes, morphine N -demethylation correlated with testosterone 6 β -hydroxylation (r = 0.91, p <0.001) and paclitaxel 6- α hydroxylation (r = 0.72, p <0.001), two specific markers of CYP3A4 and CYP2C8, respectively. Normorphine formation decreased when incubated in the presence of troleandomycin or quercetin (by 46 and 33-36%, respectively), which further corroborates the contribution of CYP3A4 and CYP2C8. 3. Among eight recombinant human CYP enzymes tested, CYP3A4 and CYP2C8 exhibited the highest intrinsic clearance. More than 90% of morphine N -demethylation could be accounted for via the action of both CYP3A4 and CYP2C8. 4. The in vitro findings suggest that hepatic CYP3A4, and to a lesser extent CYP2C8, play an important role in the metabolism of morphine into normorphine. 相似文献
38.
Marie-Ève Boulay Claudia Pruneau-Pomerleau Hélène Villeneuve Francine Deschesnes Lyne Ringuette 《The Journal of asthma》2018,55(3):231-243
Background: A “frequent exacerbator phenotype” has been described, mostly in the population of patients with severe asthma. Further data are needed on such exacerbation-prone patients in milder asthma. Aim: To compare the characteristics of frequent and nonfrequent exacerbators in asthma of different severities and to assess the stability of the exacerbator status. Methods: This was an observational study comparing baseline data from frequent (≥2 exacerbations in the past year) and nonfrequent (<2 exacerbations in the past year) exacerbators. Patients were also followed up for one year. Information regarding clinical, physiologic, and inflammatory characteristics was collected at baseline and one-year follow-up. Results: Forty-seven frequent and 53 nonfrequent exacerbators were recruited. No specific clinical, physiologic, or inflammatory characteristic was observed in the frequent as compared to the nonfrequent exacerbators at baseline. Fifty-eight percent of patients reporting frequent exacerbations at baseline remained in this group after one year of follow-up. Forty-two and 62% of patients with, respectively, mild-to-moderate asthma and severe asthma had frequent exacerbations. In a post hoc analysis according to asthma severity, frequent exacerbators with severe asthma had a higher body mass index and poorer asthma control, although they reported higher adherence to medication, in comparison to frequent exacerbators with mild-to-moderate asthma. No specific characteristics could discriminate between frequent and nonfrequent exacerbators of the same asthma severity. Conclusions: Frequent exacerbators with severe asthma present some specific characteristics not observed in frequent exacerbators with mild-to-moderate disease. However, the latter group should be identified to reassess treatment needs and potential contributing factors. 相似文献
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