全文获取类型
| 收费全文 | 2491636篇 |
| 免费 | 160008篇 |
| 国内免费 | 3465篇 |
专业分类
| 耳鼻咽喉 | 34801篇 |
| 儿科学 | 80384篇 |
| 妇产科学 | 66716篇 |
| 基础医学 | 361052篇 |
| 口腔科学 | 68780篇 |
| 临床医学 | 223825篇 |
| 内科学 | 475091篇 |
| 皮肤病学 | 55105篇 |
| 神经病学 | 193447篇 |
| 特种医学 | 93858篇 |
| 外国民族医学 | 559篇 |
| 外科学 | 372000篇 |
| 综合类 | 50479篇 |
| 现状与发展 | 11篇 |
| 一般理论 | 832篇 |
| 预防医学 | 188961篇 |
| 眼科学 | 57862篇 |
| 药学 | 188559篇 |
| 61篇 | |
| 中国医学 | 5225篇 |
| 肿瘤学 | 137501篇 |
出版年
| 2021年 | 19717篇 |
| 2019年 | 20342篇 |
| 2018年 | 27540篇 |
| 2017年 | 20923篇 |
| 2016年 | 23611篇 |
| 2015年 | 26290篇 |
| 2014年 | 36990篇 |
| 2013年 | 55277篇 |
| 2012年 | 76083篇 |
| 2011年 | 80773篇 |
| 2010年 | 48073篇 |
| 2009年 | 45101篇 |
| 2008年 | 75599篇 |
| 2007年 | 80613篇 |
| 2006年 | 81377篇 |
| 2005年 | 78743篇 |
| 2004年 | 75501篇 |
| 2003年 | 72364篇 |
| 2002年 | 70341篇 |
| 2001年 | 117078篇 |
| 2000年 | 120238篇 |
| 1999年 | 100938篇 |
| 1998年 | 28297篇 |
| 1997年 | 25033篇 |
| 1996年 | 25296篇 |
| 1995年 | 23755篇 |
| 1994年 | 21810篇 |
| 1993年 | 20576篇 |
| 1992年 | 77644篇 |
| 1991年 | 75476篇 |
| 1990年 | 73983篇 |
| 1989年 | 71320篇 |
| 1988年 | 65302篇 |
| 1987年 | 63845篇 |
| 1986年 | 60038篇 |
| 1985年 | 57095篇 |
| 1984年 | 42198篇 |
| 1983年 | 36021篇 |
| 1982年 | 21059篇 |
| 1979年 | 38755篇 |
| 1978年 | 27111篇 |
| 1977年 | 23159篇 |
| 1976年 | 21588篇 |
| 1975年 | 23522篇 |
| 1974年 | 27989篇 |
| 1973年 | 26718篇 |
| 1972年 | 25362篇 |
| 1971年 | 23991篇 |
| 1970年 | 22159篇 |
| 1969年 | 21178篇 |
排序方式： 共有10000条查询结果，搜索用时 359 毫秒
71.
Syed-Rehan A. Hussain Asuncion Mejias Octavio Ramilo Mark. E. Peeples 《Expert Review of Clinical Immunology》2019,15(1):49-58
Introduction: In early childhood, wheezing due to lower respiratory tract illness is often associated with infection by commonly known respiratory viruses such as respiratory syncytial virus (RSV) and human rhinovirus (RV). How respiratory viral infections lead to wheeze and/or asthma is an area of active research.
Areas covered: This review provides an updated summary of the published information on the development of post-viral induced atopy and asthma and the mechanisms involved. We focus on the contribution of animal models in identifying pathways that may contribute to atopy and asthma following respiratory virus infection, different polymorphisms that have been associated with asthma development, and current options for disease management and potential future interventions.
Expert commentary: Currently there are no prophylactic therapies that prevent infants infected with respiratory viruses from developing asthma or atopy. Neither are there curative therapies for patients with asthma. Therefore, a better understanding of genetic factors and other associated biomarkers in respiratory viral induced pathogenesis is important for developing effective personalized therapies. 相似文献
72.
Matthew R. Boylan James D. Slover Joan Kelly Lorraine H. Hutzler Joseph A. Bosco 《The Journal of arthroplasty》2019,34(3):408-411
Background
Private hospital rooms have a number of potential advantages compared to shared rooms, including reduced noise and increased control over the hospital environment. However, the association of room type with patient experience metrics in total joint arthroplasty (TJA) patients is currently unclear.Methods
For private versus shared rooms, we compared our institutional Hospital Consumer Assessment of Healthcare Providers and Systems (HCAHPS) scores in patients who underwent primary TJA over a 2-year period. Regression model odds ratios (ORs) were adjusted for surgeon, date of surgery, and length of stay.Results
Patients in private rooms were more likely to report a top-box score for overall hospital rating (85.6% vs 79.4%, OR = 1.53, P = .011), hospital recommendation (89.3% vs 83.0%, OR = 1.78, P = .002), call button help (76.0% vs 68.7%, OR = 1.40, P = .028), and quietness (70.4% vs 59.0%, OR = 1.78, P < .001). There were no significant differences on surgeon metrics including listening (P = .225), explanations (P = .066), or treatment with courtesy and respect (P = .396).Conclusion
For patients undergoing TJA, private hospital rooms were associated with superior performance on patient experience metrics. This association appears specific for global and hospital-related metrics, with little impact on surgeon evaluations. With the utilization of HCAHPS data in value-based initiatives, placement of TJA patients in private rooms may lead to increased reimbursement and higher hospital rankings.Level of Evidence
Level III, retrospective cohort. 相似文献73.
J. Rodríguez-Carrio A. Martínez-Zapico I. Cabezas-Rodríguez L. Benavente Á.I. Pérez-Álvarez P. López J.B. Cannata-Andía M. Naves-Díaz A. Suárez 《Nutrition, metabolism, and cardiovascular diseases : NMCD》2019,29(2):135-143
Background and aims
Since accelerated atherosclerosis has been reported in systemic lupus erythematosus (SLE), predictive biomarkers of cardiovascular disease (CVD) are needed. Among non-traditional risk factors, bone mineral density (BMD) has been related to CVD. However, its role in SLE remains controversial. This study aims to analyze the associations of subclinical atherosclerosis with traditional and non-traditional CV risk factors.Methods and results
In a cross-sectional study, atherosclerosis burden was compared between 112 female SLE patients and 31 controls. Plaque number and carotid intima-media wall thickness (cIMT) were assessed by ultrasonography. In a retrospective study, BMD determinations obtained 5-years before the ultrasonography assessment were analyzed in a subgroup of 62 patients. Plaque frequency was increased in SLE, even in patients without CV events or carotid wall thickening. cIMT was increased in patients with CVD, positively correlated with body mass index (BMI). Interestingly, a paradoxical effect of BMI on carotid parameters was observed. Whereas underweight patients (BMI < 20) showed increased prevalence of carotid plaques with low cIMT, those with BMI > 30 showed higher cIMT and plaque burden. Overweight patients (25 < BMI<30) exhibited both elevated cIMT and plaque number. BMI was an independent predictor of BMD. In our retrospective study, patients with either clinical or subclinical CVD exhibited lower BMD levels than their CV-free counterparts. A low lumbar spine BMD independently predicted CVD development after adjusting for confounders.Conclusion
SLE was associated with a higher subclinical atherosclerosis burden, a bimodal effect being observed for BMI. Decreased BMD can be a CV risk biomarker in SLE. 相似文献74.
Partha Sardar Deepak L. Bhatt Ajay J. Kirtane Kevin F. Kennedy Saurav Chatterjee Jay Giri Peter A. Soukas William B. White Sahil A. Parikh Herbert D. Aronow 《Journal of the American College of Cardiology》2019,73(13):1633-1642
Background
There are conflicting data regarding the relative effectiveness of renal sympathetic denervation (RSD) in patients with hypertension.Objectives
The purpose of this study was to evaluate the blood pressure (BP) response after RSD in sham-controlled randomized trials.Methods
Databases were searched through June 30, 2018. Randomized trials (RCTs) with ≥50 patients comparing catheter-based RSD with a sham control were included. The authors calculated summary treatment estimates as weighted mean differences (WMD) with 95% confidence intervals (CIs) using random-effects meta-analysis.Results
The analysis included 977 patients from 6 trials. The reduction in 24-h ambulatory systolic blood pressure (ASBP) was significantly greater for patients treated with RSD than sham procedure (WMD ?3.65 mm Hg, 95% CI: ?5.33 to ?1.98; p < 0.001). Compared with sham, RSD was also associated with a significant decrease in daytime ASBP (WMD ?4.07 mm Hg, 95% CI: ?6.46 to ?1.68; p < 0.001), office systolic BP (WMD ?5.53 mm Hg, 95% CI: ?8.18 to ?2.87; p < 0.001), 24-h ambulatory diastolic BP (WMD ?1.71 mm Hg, 95% CI: ?3.06 to ?0.35; p = 0.01), daytime ambulatory diastolic BP (WMD ?1.57 mm Hg, 95% CI: ?2.73 to ?0.42; p = 0.008), and office diastolic BP (WMD ?3.37 mm Hg, 95% CI: ?4.86 to ?1.88; p < 0.001). Compared with first-generation trials, a significantly greater reduction in daytime ASBP was observed with RSD in second-generation trials (6.12 mm Hg vs. 2.14 mm Hg; p interaction = 0.04); however, this interaction was not significant for 24-h ASBP (4.85 mm Hg vs. 2.23 mm Hg; p interaction = 0.13).Conclusions
RSD significantly reduced blood pressure compared with sham control. Results of this meta-analysis should inform the design of larger, pivotal trials to evaluate the long-term efficacy and safety of RSD in patients with hypertension. 相似文献75.
Hanna Lee Mary K. Tan Andrew T. Yan Paul Angaran Paul Dorian Claudia Bucci Jean C. Gregoire Alan D. Bell Martin S. Green Peter L. Gross Allan Skanes Charles R. Kerr L. Brent Mitchell Jafna L. Cox Vidal Essebag Brett Heilbron Krishnan Ramanathan Carl Fournier Shaun G. Goodman 《The Canadian journal of cardiology》2019,35(2):160-168
Background
Physicians treating nonvalvular atrial fibrillation (AF) assess stroke and bleeding risks when deciding on anticoagulation. The agreement between empirical and physician-estimated risks is unclear. Furthermore, the association between patient and physician sex and anticoagulation decision-making is uncertain.Methods
We pooled data from 2 national primary care physician chart audit databases of patients with AF (Facilitating Review and Education to Optimize Stroke Prevention in Atrial Fibrillation and Coordinated National Network to Engage Physicians in the Care and Treatment of Patients with Atrial Fibrillation Chart Audit) with a combined 1035 physicians (133 female, 902 male) and 10,927 patients (4567 female and 6360 male).Results
Male physicians underestimated stroke risk in female patients and overestimated risk in male patients. Female physicians estimated stroke risk well in female patients but underestimated the risk in male patients. Risk of bleeding was underestimated in all. Despite differences in risk assessment by physician and patient sex, > 90% of patients received anticoagulation across all subgroups. There was modest agreement between physician estimated and calculated (ie, CHADS2 score) stroke risk: Kappa scores were 0.41 (0.35-0.47) for female physicians and 0.34 (0.32-0.36) for male physicians.Conclusions
Our study is the first to examine the association between patient and physician sex influences and stroke and bleeding risk estimation in AF. Although there were differences in agreement between physician estimated stroke risk and calculated CHADS2 scores, these differences were small and unlikely to affect clinical practice; further, despite any perceived differences in the accuracy of risk assessment by sex, most patients received anticoagulation. 相似文献76.
K.-C. Sung D.-C. Seo S.-J. Lee M.-Y. Lee S.H. Wild C.D. Byrne 《Nutrition, metabolism, and cardiovascular diseases : NMCD》2019,29(5):489-495
Background and aims
It is not known whether non alcoholic fatty liver disease (NAFLD) is a risk factor for diabetes in non obese, non centrally-obese subjects. Our aim was to investigate relationships between fatty liver, insulin resistance and a biomarker score for liver fibrosis with incident diabetes at follow up, in subjects who were neither obese nor centrally-obese.Methods and results
As many as 70,303 subjects with a body mass index (BMI) < 25 kg/m2 and without diabetes were followed up for a maximum of 7.9 years. At baseline, fatty liver was identified by liver ultrasound, insulin resistance (IR) by homeostatic model assessment of insulin resistance (HOMA-IR) ≥2.0, and central obesity by waist circumference (waist circumference ≥90 cm (men) and ≥85 cm (women). The Fibrosis-4 (FIB-4 score) was used to estimate extent of liver fibrosis. Cox proportional hazards models adjusted for confounders were used to estimate hazard ratios (aHRs) for incident diabetes. As many as 852 incident cases of diabetes occurred during follow up (median [IQR] 3.71 [2.03] years). Mean ± SD BMI was 22.8 ± 1.8 and 21.7 ± 2.0 kg/m2 in subjects with and without diabetes at follow up. In subjects without central obesity and with fatty liver, aHRs (95% CI) for incident diabetes at follow up were 2.17 (1.56, 3.03) for men, and 2.86 (1.50,5.46) for women. Similar aHRs for incident diabetes occurred with fatty liver, IR and the highest quartile of FIB-4 combined, in men; and there was a non significant trend toward increased risk in women.Conclusions
In normal weight, non-centrally obese subjects NAFLD is an independent risk factor for incident diabetes. 相似文献77.
78.
Anaïs Potron Maxime Bour Pauline Triponney Joris Muller Christelle Koebel Rémy A. Bonnin Patrick Plésiat 《International journal of antimicrobial agents》2019,53(5):669-673
Objectives
This study reported a hospital outbreak due to an extensively drug-resistant (XDR) OXA-72-producing strain of Acinetobacter baumannii (A. baumannii).Methods and Results
The isolates were found to be genotypically indistinguishable by whole-genome multiple locus sequence typing, and to belong to the international clonal complex CC2. One of these isolates sequentially developed a high resistance to colistin and rifampicin under treatment, as a result of mutations in genes pmrB and rpoB, respectively. The blaOXA-72 gene was localised on a 10-kb transferable plasmid, named pAB-STR-1, whose sequence is nearly identical to that of another plasmid previously found in Lithuanian strains, pAB120.Conclusion
This report highlighted the need to carefully monitor the emergence of colistin and rifampicin resistance in patients treated for infections with multidrug-resistant A. baumannii. 相似文献79.
Otavio Berwanger Renato D. Lopes Diogo D.F. Moia Francisco A. Fonseca Lixin Jiang Shaun G. Goodman Stephen J. Nicholls Alexander Parkhomenko Oleg Averkov Carlos Tajer Germán Malaga Jose F.K. Saraiva Helio P. Guimaraes Pedro G.M. de Barros e Silva Lucas P. Damiani Renato H.N. Santos Denise M. Paisani Tamiris A. Miranda Jose C. Nicolau 《Journal of the American College of Cardiology》2019,73(22):2819-2828
BackgroundThe efficacy of ticagrelor in the long-term post–ST-segment elevation myocardial infarction (STEMI) treated with fibrinolytic therapy remains uncertain.ObjectivesThe purpose of this study was to evaluate the efficacy of ticagrelor when compared with clopidogrel in STEMI patients treated with fibrinolytic therapy.MethodsThis international, multicenter, randomized, open-label with blinded endpoint adjudication trial enrolled 3,799 patients (age <75 years) with STEMI receiving fibrinolytic therapy. Patients were randomized to ticagrelor (180-mg loading dose, 90 mg twice daily thereafter) or clopidogrel (300- to 600-mg loading dose, 75 mg daily thereafter). The key outcomes were cardiovascular mortality, myocardial infarction, or stroke, and the same composite outcome with the addition of severe recurrent ischemia, transient ischemic attack, or other arterial thrombotic events at 12 months.ResultsThe combined outcome of cardiovascular mortality, myocardial infarction, or stroke occurred in 129 of 1,913 patients (6.7%) receiving ticagrelor and in 137 of 1,886 patients (7.3%) receiving clopidogrel (hazard ratio: 0.93; 95% confidence interval: 0.73 to 1.18; p = 0.53). The composite of cardiovascular mortality, myocardial infarction, stroke, severe recurrent ischemia, transient ischemic attack, or other arterial thrombotic events occurred in 153 of 1,913 patients (8.0%) treated with ticagrelor and in 171 of 1,886 patients (9.1%) receiving clopidogrel (hazard ratio: 0.88; 95% confidence interval: 0.71 to 1.09; p = 0.25). The rates of major, fatal, and intracranial bleeding were similar between the ticagrelor and clopidogrel groups.ConclusionAmong patients age <75 years with STEMI, administration of ticagrelor after fibrinolytic therapy did not significantly reduce the frequency of cardiovascular events when compared with clopidogrel. (Ticagrelor in Patients With ST Elevation Myocardial Infarction Treated With Pharmacological Thrombolysis [TREAT]; NCT02298088) 相似文献
80.
M. Tobias Heinrichs George L. Drusano David L. Brown Michael S. Maynard Sherwin K.B. Sy Kenneth H. Rand Charles A. Peloquin Arnold Louie Hartmut Derendorf 《International journal of antimicrobial agents》2019,53(3):275-283