全文获取类型
收费全文 | 711620篇 |
免费 | 49309篇 |
国内免费 | 17755篇 |
专业分类
耳鼻咽喉 | 9503篇 |
儿科学 | 18540篇 |
妇产科学 | 11198篇 |
基础医学 | 54924篇 |
口腔科学 | 17482篇 |
临床医学 | 79215篇 |
内科学 | 93697篇 |
皮肤病学 | 9035篇 |
神经病学 | 37678篇 |
特种医学 | 24629篇 |
外国民族医学 | 60篇 |
外科学 | 86494篇 |
综合类 | 97881篇 |
现状与发展 | 43篇 |
一般理论 | 53篇 |
预防医学 | 72154篇 |
眼科学 | 12195篇 |
药学 | 69317篇 |
737篇 | |
中国医学 | 52355篇 |
肿瘤学 | 31494篇 |
出版年
2024年 | 2259篇 |
2023年 | 10933篇 |
2022年 | 23872篇 |
2021年 | 31060篇 |
2020年 | 25614篇 |
2019年 | 30380篇 |
2018年 | 26430篇 |
2017年 | 23712篇 |
2016年 | 23615篇 |
2015年 | 25464篇 |
2014年 | 48191篇 |
2013年 | 48274篇 |
2012年 | 46296篇 |
2011年 | 45257篇 |
2010年 | 38493篇 |
2009年 | 35641篇 |
2008年 | 33454篇 |
2007年 | 34040篇 |
2006年 | 29387篇 |
2005年 | 23229篇 |
2004年 | 16861篇 |
2003年 | 14693篇 |
2002年 | 11650篇 |
2001年 | 10109篇 |
2000年 | 8640篇 |
1999年 | 6990篇 |
1998年 | 6385篇 |
1997年 | 5886篇 |
1996年 | 5004篇 |
1995年 | 4845篇 |
1994年 | 4560篇 |
1993年 | 3697篇 |
1992年 | 3829篇 |
1991年 | 3385篇 |
1990年 | 3141篇 |
1989年 | 2922篇 |
1988年 | 2739篇 |
1987年 | 2420篇 |
1986年 | 2150篇 |
1985年 | 5864篇 |
1984年 | 6954篇 |
1983年 | 4936篇 |
1982年 | 5681篇 |
1981年 | 5090篇 |
1980年 | 4492篇 |
1979年 | 4062篇 |
1978年 | 3426篇 |
1977年 | 2768篇 |
1976年 | 2920篇 |
1975年 | 2120篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
51.
Could non-HDL-cholesterol be a better marker of atherogenic dyslipidemia in obstructive sleep apnea?
《Sleep medicine》2021
Background/objectiveObstructive sleep apnea (OSA) is independently associated with dyslipidemia, a surrogate marker of atherosclerosis. Low-density lipoprotein (LDL)-cholesterol is accepted as a major independent risk factor for cardiovascular disease. However, non-high-density lipoprotein (HDL)-cholesterol is a better marker of atherogenic dyslipidemia and recommended as a target of lipid lowering therapy. We aimed to assess the prevalence of atherogenic dyslipidemia, and relationship between OSA severity and serum LDL-cholesterol and non-HDL cholesterol levels in OSA patients.MethodsWe retrospectively evaluated treatment naïve 2361 subjects admitted to the sleep laboratory of a university hospital for polysomnography. All subjects’ lipid profile including total cholesterol, LDL-cholesterol, HDL-cholesterol, triglycerides, and non-HDL-cholesterol were measured.ResultsOut of 2361 patients (mean age 49.6 ± 11.9 years; 68.9% male, apnea-hypopnea index 36.6 ± 28.4/h), 185 (7.8%) had no OSA and 2176 (92.2%) had OSA. Atherogenic dyslipidemia prevalence was high (57–66%) in OSA patients, and especially increased in severe OSA compared to other groups (p < 0.05). Though total and LDL-cholesterol did not differ between those with and without OSA, non-HDL-cholesterol (p = 0.020), and triglycerides (p = 0.001) were higher and HDL-cholesterol levels (p = 0.018) were lower in OSA patients than non-OSA. Non-HDL-cholesterol was significantly correlated with OSA severity (p < 0.001) and hypoxia parameters (p < 0.01), whereas LDL-cholesterol showed no correlation.ConclusionsAtherogenic dyslipidemia is highly prevalent and non-HDL-cholesterol levels are significantly increased, predominantly in severe OSA patients. Non-HDL-cholesterol but not LDL-cholesterol, is significantly correlated with OSA severity and hypoxia parameters. Therefore, it could be better to use non-HDL-cholesterol, which is a guideline recommended target of lipid therapy, as a marker of atherosclerotic cardiovascular risk in OSA patients. 相似文献
52.
Katherine M. Duszynski Nicole L. Pratt John W. Lynch Jesia G. Berry Michael S. Gold 《Vaccine》2019,37(2):280-288
Objective
To determine whether differences in combination DTaP vaccine types at 2, 4 and 6?months of age were associated with mortality (all-cause or non-specific), within 30?days of vaccination.Design
Observational nationwide cohort study.Setting
Linked population data from the Australian Childhood Immunisation Register and National Death Index.Participants
Australian infants administered a combination trivalent, quadrivalent or hexavalent DTaP vaccine (DTaP types) between January 1999 and December 2010 at 2, 4 and 6?months as part of the primary vaccination series. The study population included 2.9, 2.6, & 2.3?million children in the 2, 4 and 6?month vaccine cohorts, respectively.Main outcome measures
Infants were evaluated for the primary outcome of all-cause mortality within 30?days. A secondary outcome was non-specific mortality (unknown cause of death) within 30?days of vaccination. Non-specific mortality was defined as underlying or other cause of death codes, R95 ‘Sudden infant death syndrome’, R96 ‘Other sudden death, cause unknown’, R98 ‘Unattended death’, R99 ‘Other ill-defined and unspecified cause of mortality’ or where no cause of death was recorded.Results
The rate of 30?day all-cause mortality was low and declined from 127.4 to 59.3 deaths per 100,000 person-years between 2 and 6?month cohorts. When compared with trivalent DTaP vaccines, no elevated risk in all-cause or non-specific mortality was seen with any quadrivalent or hexavalent DTaP vaccines, for any cohort.Conclusion
Use of routine DTaP combination vaccines with differing disease antigens administered during the first six months of life is not associated with infant mortality. 相似文献53.
54.
Thomas W. McDade Alexander V. Georgiev Christopher W. Kuzawa 《Evolution, Medicine, and Public Health》2016,2016(1):1-16
Immune defenses provide resistance against infectious disease that is critical to survival. But immune defenses are costly, and limited resources allocated to immunity are not available for other physiological or developmental processes. We propose a framework for explaining variation in patterns of investment in two important subsystems of anti-pathogen defense: innate (non-specific) and acquired (specific) immunity. The developmental costs of acquired immunity are high, but the costs of maintenance and activation are relatively low. Innate immunity imposes lower upfront developmental costs, but higher operating costs. Innate defenses are mobilized quickly and are effective against novel pathogens. Acquired responses are less effective against novel exposures, but more effective against secondary exposures due to immunological memory. Based on their distinct profiles of costs and effectiveness, we propose that the balance of investment in innate versus acquired immunity is variable, and that this balance is optimized in response to local ecological conditions early in development. Nutritional abundance, high pathogen exposure and low signals of extrinsic mortality risk during sensitive periods of immune development should all favor relatively higher levels of investment in acquired immunity. Undernutrition, low pathogen exposure, and high mortality risk should favor innate immune defenses. The hypothesis provides a framework for organizing prior empirical research on the impact of developmental environments on innate and acquired immunity, and suggests promising directions for future research in human ecological immunology. 相似文献
55.
Walid K. Abu Saleh Phillip Mason Odeaa Al Jabbari Hany Samir Brian A. Bruckner 《Texas Heart Institute journal / from the Texas Heart Institute of St. Luke's Episcopal Hospital, Texas Children's Hospital》2015,42(6):569-571
The Impella 5.0, a percutaneously inserted left ventricular assist device, has been used to support patients who have severe heart failure or who are undergoing high-risk percutaneous coronary intervention. We report our surgical placement of the Impella 5.0, through a graft sewn to the aorta, to unload the left ventricle of a 59-year-old man who was undergoing venoarterial extracorporeal membrane oxygenation for postcardiotomy shock. The patient underwent successful placement of a long-term left ventricular assist device before his discharge from the hospital. The versatility of the Impella 5.0 is exemplified in this patient who was successfully bridged to long-term support. 相似文献
56.
功能性便秘的发生严重困扰着现代人群,进而影响人们的生活质量。杜长海名老中医认为功能性便秘究其内因为大肠传导失常,外因乃现代人的生活方式、紧张的生活氛围等等,因此杜老结合自己数十年的临床经验,根据中医辨证总结出临床常用药对,对有效治疗功能性便秘进行了经验总结。 相似文献
57.
Anna Grace Tribble Phillip Summers Haiying Chen Sara A. Quandt 《Archives of environmental & occupational health》2016,71(6):309-316
The jobs of Latino manual laborers place their mental and physical health at risk. This study evaluates the associations among musculoskeletal pain, mental health, and work organization in Latino manual laborers. Farmworkers and nonfarmworkers (n = 189) in North Carolina were interviewed for self-reported musculoskeletal pain, depressive symptoms, stress, work safety climate, and precarious job status. More nonfarmworkers than farmworkers had neck and shoulder pain, but they did not differ in other areas of musculoskeletal pain. Depressive symptoms had a significant association with neck and shoulder pain (p < .05). Precariousness had a significant association with back pain (p < .05). Farmworker participants had H-2A visas and were afforded some protection compared to nonfarmworker manual workers. Research is needed to improve policy that relieves pain and improves mental health for all Latino manual workers. 相似文献
58.
59.
60.
Seulkee Heo 《International journal of environmental health research》2015,25(3):330-348
In this study, we estimated the disease burdens attributable to environmental tobacco smoke (ETS) exposure in Korean adults in 2010 and analyzed the trend of that from 2005 to 2010. We obtained information on the study population from the 2010 Cause of Death Statistic and estimated the ETS-attributable fraction using data from the Korean Community Health Survey and the Korean National Health and Nutrition Examination Survey. The numbers of ETS-attributable deaths in female and male non-smokers were estimated to be 4.1 and 69.6?% of the numbers of deaths attributable to current smoke, respectively. The deaths attributable to ETS were larger in female than in male non-smokers (710 vs. 420). The ETS-attributable deaths increased slightly in 2005–2008 but decreased in 2009–2010. The number of potential years of life lost from ETS was 9077.24?years in 2010. If there were no exposure to ETS in adult non-smokers, we would expect to see 1130 fewer deaths (9.9?% of the deaths from current smoke). The results suggest that ETS poses considerable disease burdens for non-smokers, especially women, in Korea. 相似文献