全文获取类型
收费全文 | 5285篇 |
免费 | 443篇 |
国内免费 | 10篇 |
专业分类
耳鼻咽喉 | 52篇 |
儿科学 | 143篇 |
妇产科学 | 99篇 |
基础医学 | 680篇 |
口腔科学 | 109篇 |
临床医学 | 494篇 |
内科学 | 1096篇 |
皮肤病学 | 111篇 |
神经病学 | 515篇 |
特种医学 | 171篇 |
外国民族医学 | 6篇 |
外科学 | 831篇 |
综合类 | 123篇 |
一般理论 | 8篇 |
预防医学 | 450篇 |
眼科学 | 206篇 |
药学 | 313篇 |
中国医学 | 16篇 |
肿瘤学 | 315篇 |
出版年
2022年 | 33篇 |
2021年 | 92篇 |
2020年 | 44篇 |
2019年 | 80篇 |
2018年 | 97篇 |
2017年 | 68篇 |
2016年 | 64篇 |
2015年 | 76篇 |
2014年 | 120篇 |
2013年 | 217篇 |
2012年 | 273篇 |
2011年 | 297篇 |
2010年 | 170篇 |
2009年 | 155篇 |
2008年 | 259篇 |
2007年 | 287篇 |
2006年 | 280篇 |
2005年 | 293篇 |
2004年 | 297篇 |
2003年 | 287篇 |
2002年 | 269篇 |
2001年 | 55篇 |
2000年 | 59篇 |
1999年 | 66篇 |
1998年 | 62篇 |
1997年 | 43篇 |
1996年 | 46篇 |
1995年 | 54篇 |
1994年 | 54篇 |
1993年 | 65篇 |
1992年 | 48篇 |
1991年 | 33篇 |
1990年 | 42篇 |
1989年 | 37篇 |
1988年 | 30篇 |
1987年 | 38篇 |
1986年 | 36篇 |
1985年 | 43篇 |
1984年 | 57篇 |
1983年 | 49篇 |
1982年 | 47篇 |
1981年 | 63篇 |
1980年 | 54篇 |
1979年 | 47篇 |
1978年 | 48篇 |
1977年 | 49篇 |
1976年 | 35篇 |
1975年 | 34篇 |
1974年 | 42篇 |
1973年 | 39篇 |
排序方式: 共有5738条查询结果,搜索用时 312 毫秒
991.
Rationale
Obstructive sleep apnea results in nocturnal intermittent hypoxia (IH) as a main trigger for cardiovascular morbidity, including atherosclerosis. IH induces hemodynamic, hormono-metabolic and also immuno-inflammatory alterations that could differentially contribute to atherosclerosis. Our study aimed at examining their respective contribution to the proatherogenic role of IH in atherosclerosis-prone mice.Methods
Fifteen-week-old male apolipoprotein E-deficient (ApoE−/−) mice fed on a high-cholesterol diet (HCD) for 6 weeks and exposed for the last 14 days to IH (21–5% FiO2, 60 s cycle, 8 h/day) or air, were investigated for aortic atherosclerosis and lipid alterations. Then IH proatherogenicity was assessed in 15- and 20-week-old ApoE−/− mice fed on a standart-chow diet (SCD) exposed to IH or air for 14 days and assessed for atherosclerosis, lipid, hemodynamic and inflammation alterations.Results
IH aggravated atherosclerosis in HCD-fed mice, whereas the extremely high cholesterol levels due to HCD were not different between normoxic and hypoxic animals. In SCD-fed mice, IH also aggravated atherosclerosis, more severely in 20 compared to 15-week-old animals. However, cholesterol levels that increased with IH were not different in the two SCD-fed groups. IH slightly elevated arterial blood pressure in 20-week-old animals only, and induced systemic and vascular inflammation, including increased splenocyte proliferation with decreased IL-10 secretion, and increased T-lymphocytes within atherosclerotic plaques.Conclusions
A short IH exposure without HCD has proatherogenic effects. In contrast to blood pressure or plasma lipids which were slightly or inconstantly affected by IH, inflammation at systemic and vascular levels appears as a potential contributing factor to IH atherogenicity. 相似文献992.
Fischer K Pouw ME Lewandowski D Janssen MP van den Berg HM van Hout BA 《Haematologica》2011,96(5):738-743
Background
Severe hemophilia requires life-long treatment with expensive clotting factor concentrates; studies comparing effects of different therapeutic strategies over decades are very difficult to perform. A simulation model was developed to evaluate the long-term outcome of on demand, prophylactic and mixed treatment strategies for patients with severe hemophilia A.Design and Methods
A computer model was developed based on individual patients’ data from a Dutch cohort study in which intermediate dose prophylaxis was used and a French cohort study in which on demand treatment was used, and multivariate regression analyses. This model simulated individual patients’ life expectancy, onset of bleeding, life-time joint bleeds, radiological outcome and concentrate use according to the different treatment strategies.Results
According to the model, life-time on demand treatment would result in an average of 1,494 joint bleeds during the hemophiliac’s life, and consumption of 4.9 million IU of factor VIII concentrate. In contrast, life-time intermediate dose prophylaxis resulted in a mean of 357 joint bleeds and factor consumption of 8.3 million IU. A multiple switch strategy (between prophylactic and on demand treatment based on bleeding pattern) resulted in a mean number of 395 joint bleeds and factor consumption of 6.6 million IU. The estimated proportion of patients with Pettersson scores over 28 points was 32% for both the prophylactic and the multiple switching strategies, compared to 76% for continuous on demand treatment.Conclusions
The present model allows evaluation of the impact of various treatment strategies on patients’ joint bleeds and clotting factor consumption. It may be expanded with additional data to allow more precise estimates and include economic evaluations of treatment strategies. 相似文献993.
994.
995.
This article gives an overview of genetic and environmental risk factors for schizophrenia. The presence of certain molecular, biological, and psychosocial factors at certain points in the life span, has been linked to later development of schizophrenia. All need to be considered in the context of schizophrenia as a lifelong brain disorder. Research interest in schizophrenia is shifting to late childhood/early adolescence for screening and preventative measures. This article discusses those environmental risk factors for schizophrenia for which there is the largest evidence base. 相似文献
996.
997.
998.
Philip S. Hall Colin I. O’Donnell Verghese Mathew Santiago Garcia Anthony A. Bavry Subhash Banerjee Hani Jneid Ali E. Denktas John C. Giacomini Paul M. Grossman Kul Aggarwal Jeffrey M. Zimmet Elaine E. Tseng Leo Gozdecki Lucas Burke Stefan C. Bertog Maurice Buchbinder Mary E. Plomondon Kendrick A. Shunk 《JACC: Cardiovascular Interventions》2019,12(21):2186-2194
ObjectivesThis study sought to describe clinical and procedural characteristics of veterans undergoing transcatheter aortic valve replacement (TAVR) within U.S. Department of Veterans Affairs (VA) centers and to examine their association with short- and long-term mortality, length of stay (LOS), and rehospitalization within 30 days.BackgroundVeterans with severe aortic stenosis frequently undergo TAVR at VA medical centers.MethodsConsecutive veterans undergoing TAVR between 2012 and 2017 were included. Patient and procedural characteristics were obtained from the VA Clinical Assessment, Reporting, and Tracking system. The primary outcomes were 30-day and 1-year survival, LOS >6 days, and rehospitalization within 30 days. Logistic regression and Cox proportional hazards analyses were performed to evaluate the associations between pre-procedural characteristics and LOS and rehospitalization.ResultsNine hundred fifty-nine veterans underwent TAVR at 8 VA centers during the study period, 860 (90%) by transfemoral access, 50 (5%) transapical, 36 (3.8%) transaxillary, and 3 (0.3%) transaortic. Men predominated (939 of 959 [98%]), with an average age of 78.1 years. There were 28 deaths within 30 days (2.9%) and 134 at 1 year (14.0%). Median LOS was 5 days, and 141 veterans were rehospitalized within 30 days (14.7%). Nonfemoral access (odds ratio: 1.74; 95% confidence interval [CI]: 1.10 to 2.74), heart failure (odds ratio: 2.51; 95% CI: 1.83 to 3.44), and atrial fibrillation (odds ratio: 1.40; 95% CI: 1.01 to 1.95) were associated with increased LOS. Atrial fibrillation was associated with 30-day rehospitalization (hazard ratio: 1.79; 95% CI: 1.22 to 2.63).ConclusionsVeterans undergoing TAVR at VA centers are predominantly elderly men with significant comorbidities. Clinical outcomes of mortality and rehospitalization at 30 days and 1-year mortality compare favorably with benchmark outcome data outside the VA. 相似文献
999.
1000.