全文获取类型
收费全文 | 201028篇 |
免费 | 44100篇 |
国内免费 | 308篇 |
专业分类
耳鼻咽喉 | 3471篇 |
儿科学 | 8041篇 |
妇产科学 | 3315篇 |
基础医学 | 31794篇 |
口腔科学 | 9058篇 |
临床医学 | 19418篇 |
内科学 | 53754篇 |
皮肤病学 | 10905篇 |
神经病学 | 22498篇 |
特种医学 | 5010篇 |
外国民族医学 | 1篇 |
外科学 | 29072篇 |
综合类 | 684篇 |
一般理论 | 58篇 |
预防医学 | 16542篇 |
眼科学 | 4027篇 |
药学 | 14002篇 |
中国医学 | 1591篇 |
肿瘤学 | 12195篇 |
出版年
2023年 | 831篇 |
2022年 | 718篇 |
2021年 | 3983篇 |
2020年 | 6348篇 |
2019年 | 13646篇 |
2018年 | 14323篇 |
2017年 | 13523篇 |
2016年 | 13989篇 |
2015年 | 14221篇 |
2014年 | 14587篇 |
2013年 | 16851篇 |
2012年 | 13000篇 |
2011年 | 13535篇 |
2010年 | 13391篇 |
2009年 | 8521篇 |
2008年 | 9712篇 |
2007年 | 9144篇 |
2006年 | 8578篇 |
2005年 | 8286篇 |
2004年 | 7410篇 |
2003年 | 7021篇 |
2002年 | 6710篇 |
2001年 | 4614篇 |
2000年 | 5154篇 |
1999年 | 3608篇 |
1998年 | 578篇 |
1997年 | 371篇 |
1996年 | 362篇 |
1995年 | 291篇 |
1994年 | 223篇 |
1992年 | 1290篇 |
1991年 | 1070篇 |
1990年 | 946篇 |
1989年 | 780篇 |
1988年 | 640篇 |
1987年 | 622篇 |
1986年 | 623篇 |
1985年 | 528篇 |
1984年 | 397篇 |
1983年 | 297篇 |
1979年 | 335篇 |
1975年 | 268篇 |
1974年 | 315篇 |
1973年 | 349篇 |
1972年 | 290篇 |
1971年 | 314篇 |
1970年 | 292篇 |
1969年 | 292篇 |
1968年 | 269篇 |
1967年 | 236篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
81.
82.
83.
Eduardo Carracedo-Martínez Agustin Pia-Morandeira 《Atencion primaria / Sociedad Espa?ola de Medicina de Familia y Comunitaria》2009,41(6):324-328
ObjectiveTo assess whether the release of the new consensus algorithms in August 2006, along with the consensus recommendation of also using metformin as first choice in patients with normal weight, has led to an increase in the use of this drug in the period immediately after.DesignRetrospective longitudinal Study.SitesSantiago de Compostela Health District (A Coruña).ParticipantsUsers of the Galician health service in the Santiago de Compostela Health District.MethodsThe evolution of the monthly number of DHD (Daily Defined Doses/1000 inhabitants/day) of metformin from early 2003 until 12 months after the issuing of new algorithms was analysed graphically and using a multiple regression model.ResultsThe graphical representation of the DHD of metformin over time shows a linear growth for the period, but there is an increasing trend after the publication of the new consensus algorithm. The multiple regression showed that the increase is statistically significant.ConclusionsFollowing the publication of the new consensus algorithm an increasing trend in the use of metformin is observed in the short term. 相似文献
84.
85.
David Jiménez Castro Gema Díaz David Martí Carlos Escobar Javier Ortega Sergio García-Rull Joaquin Picher Antonio Sueiro 《Blood coagulation & fibrinolysis》2007,18(2):173-177
This study aimed to determine whether a weight-adjusted dose of subcutaneous enoxaparin is as effective and safe as oral acenocoumarol for the secondary prophylaxis of pulmonary embolism. Three hundred and eighty consecutive noncancer outpatients hospitalized with an episode of symptomatic pulmonary embolism selected treatment with acenocoumarol or enoxaparin at a dose of 1 mg/kg once daily after being informed of the type of administration and expected frequency of laboratory monitoring for both medicinal products. Endpoints were symptomatic recurrent thromboembolic events evaluated by standard objective testing, and a composite endpoint of recurrent venous thromboembolism, major bleeding, and death from any cause. One hundred and ninety-nine patients (52%) chose acenocoumarol therapy and 181 chose enoxaparin monotherapy. Four patients in the enoxaparin group (2.2%) and six patients in the acenocoumarol group (3%) had an objective thromboembolic recurrence (hazard ratio, 1.35; 95% confidence interval, 0.38-4.79; P = 0.64). Nine patients in the enoxaparin group (5.0%) had a hemorrhagic complication compared with 11 in the acenocoumarol group (5.5%) (P = 0.81). The hospital length of stay was shorter with enoxaparin compared with acenocoumarol (11 versus 16 days, P = 0.0001). Enoxaparin is as effective and safe as acenocoumarol in the secondary prevention of recurrent thromboembolic disease and is associated with shorter hospitalization. 相似文献
86.
D-dimer has proved a useful diagnostic tool for the exclusion of deep venous thrombosis (DVT). The objective of this paper was to evaluate the diagnostic performance of a diagnostic algorithm combining clinical probability and D-dimer in outpatients receiving oral anticoagulant treatment (OAT) similar to those regularly applied to nonanticoagulated individuals. We enrolled 70 outpatients on OAT who presented with clinically suspected DVT; a standard diagnostic algorithm including clinical evaluation using the modified Wells score and a quantitative immunoturbidimetric D-dimer assay (STA Liatest D-Di; Diagnostica Stago, Asniéres sur Seine, France) was used. A 3-month follow-up period was applied for those patients in whom DVT was initially excluded. The prevalence of DVT was 18.5% (13/70); four of the diagnoses were made during the 3-month follow-up period. The sensitivity, specificity and negative predictive value of D-dimer were 69.2% (95 confidence interval, 42.4-87.3), 47.4% (95% confidence interval, 35.0-60.1) and 87.1% (95% confidence interval, 71.1-94.9), respectively. In conclusion, D-dimer is of limited value in outpatients on OAT presenting with clinically suspected DVT and should be omitted in such individuals; these patients should always undergo compression venous ultrasound, and repeat ultrasonography within 1 week might be warranted in cases with an initial negative examination. 相似文献
87.
Plasma levels and vascular effects of vasopressin in patients undergoing coronary artery bypass grafting. 总被引:1,自引:0,他引:1
Susana Novella Ana Cristina Martínez Rosa María Pagán Medardo Hernández Albino García-Sacristán Angel González-Pinto José María González-Santos Sara Benedito 《European journal of cardio-thoracic surgery》2007,32(1):69-76
OBJECTIVE: Recent studies have suggested that endogenous vasopressin (AVP) acts as a spasmogen during coronary artery bypass grafting (CABG). Given that AVP could induce vasospasm in the grafted vessel, we assessed the release of this peptide during and after CABG, and explored ways of counteracting its contractile effect on the internal mammary artery (IMA). METHODS: Plasma levels of AVP were determined by radioimmunoassay in 16 patients before, during and after CABG. Using isometric force recording techniques, we also investigated the mechanisms involved in the contractile effect of AVP in ring preparations of IMA specimens taken from 95 patients. RESULTS: Plasma AVP levels peaked after the start of cardiopulmonary bypass (CPB) and correlated well with serum osmolality (Pearson's r=0.9490; P<0.0001; n=16). An inverse correlation was observed between plasma AVP levels recorded at this stage and the maximal contraction induced in vitro by AVP in vascular rings from the same patients (Pearson's r=-0.6968; P<0.01; n=16). No change in the AVP response was produced by endothelium removal, exposure to the NO precursor (3 x 10(-4)M L-arginine), inhibition of nitric oxide (NO) synthase (3 x 10(-5) M L-NAME) or soluble guanylate cyclase (3 x 10(-6) M 1H-[1,2,4]oxadiazol [4,3,-alpha]quinoxalin-1-one (ODQ)), removal of the superoxide anion (100 U/ml superoxide dismutase (SOD) plus 1200 U/ml catalase) or hydroxyl radical (10(-4) M deferoxamine), or specific alpha1 - (10(-6) M prazosin) or endothelin (10(-5) M bosentan) receptor antagonism. In contrast, adenylate cyclase activation (3 x 10(-8) M forskolin) reduced the contractile response to AVP, while prostanoid synthesis (3 x 10(-6) M indomethacin) inhibition and blockade of Ca2+ -activated potassium channels (KCa) (10(-3) M tetraethylammonium (TEA)) enhanced AVP contraction. Age, gender and smoking also modified the AVP response. CONCLUSION: Our findings suggest a role for AVP as a modulator of vascular tone in human IMA. The effect of AVP is dependent on prostanoids and Ca2+ -activated K+ channels, so its dysfunction in pathophysiological cardiovascular processes could mean that AVP, among other factors, produces vasospasm in IMA grafts. 相似文献
88.
Marina H C G Magalh?es Cristiane Barbosa da Silveira Carla Ruffeil Moreira Marcelo Gusm?o Paraíso Cavalcanti 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2007,103(6):836-842
Mandibulofacial dysostosis (Treacher Collins Syndrome) is an autosomal dominant genetic disorder that probably derives from inhibition of the facial structures from the first and second branchial arches. The facial pattern of the syndrome is a convex facial profile with a prominent nose above a retruded chin. The eyes are deformed by antimongoloid slant of the palpebral fissures and facial bones are hypoplastic. The alterations are caused by mutation in gene 5q32-33.1, which encodes the nucleolar phosphoprotein treacle. Computed tomography images are able to demonstrate craniofacial bones, allowing the morphological analysis of these bones in individuals with complex deformities. The purpose of this paper is to present the results of a clinical and computed tomography investigation of two patients with Treacher Collins syndrome. 相似文献
89.
90.