全文获取类型
收费全文 | 1628篇 |
免费 | 134篇 |
国内免费 | 59篇 |
专业分类
耳鼻咽喉 | 4篇 |
儿科学 | 59篇 |
妇产科学 | 24篇 |
基础医学 | 136篇 |
口腔科学 | 25篇 |
临床医学 | 241篇 |
内科学 | 392篇 |
皮肤病学 | 67篇 |
神经病学 | 56篇 |
特种医学 | 243篇 |
外科学 | 133篇 |
综合类 | 43篇 |
一般理论 | 2篇 |
预防医学 | 174篇 |
眼科学 | 36篇 |
药学 | 140篇 |
中国医学 | 2篇 |
肿瘤学 | 44篇 |
出版年
2021年 | 19篇 |
2019年 | 11篇 |
2018年 | 34篇 |
2017年 | 14篇 |
2016年 | 15篇 |
2015年 | 17篇 |
2014年 | 30篇 |
2013年 | 52篇 |
2012年 | 58篇 |
2011年 | 63篇 |
2010年 | 47篇 |
2009年 | 41篇 |
2008年 | 54篇 |
2007年 | 98篇 |
2006年 | 43篇 |
2005年 | 49篇 |
2004年 | 44篇 |
2003年 | 42篇 |
2002年 | 38篇 |
2001年 | 33篇 |
2000年 | 27篇 |
1999年 | 35篇 |
1998年 | 63篇 |
1997年 | 46篇 |
1996年 | 71篇 |
1995年 | 50篇 |
1994年 | 51篇 |
1993年 | 55篇 |
1992年 | 25篇 |
1991年 | 24篇 |
1990年 | 25篇 |
1989年 | 41篇 |
1988年 | 43篇 |
1987年 | 49篇 |
1986年 | 42篇 |
1985年 | 47篇 |
1984年 | 31篇 |
1983年 | 23篇 |
1982年 | 20篇 |
1981年 | 33篇 |
1980年 | 22篇 |
1979年 | 19篇 |
1978年 | 16篇 |
1977年 | 23篇 |
1976年 | 13篇 |
1975年 | 16篇 |
1974年 | 10篇 |
1973年 | 13篇 |
1972年 | 14篇 |
1968年 | 11篇 |
排序方式: 共有1821条查询结果,搜索用时 0 毫秒
11.
12.
A total of 75 BALB/cStCrlfC3H/Nctr male weanling mice were administered either 0 or 250 ppm of 4 ethylsulfonylnaphthalene-1-sulfonamide (ENS) in the diet for periods up to 14 days to evaluate the early morphological changes of the transitional epithelium of the urinary bladder with scanning (SEM) and transmission (TEM) electron microscopy. Primary TEM changes included hyperplasia of the epithelium, loosening of the intercellular junctions, autophagic vacuoles and electron dense granules in the mitochondria. Primary SEM changes included sloughing of epithelial cells, irregularity in the size and shape of the transitional epithelial cells and the presence of microvilli. Although pleomorphic microvilli were present after only three days of treatment with ENS, it appears that they are a transient observation in a series of morphological changes. The reversibility or transient nature of the pleomorphic microvilli may indicate that they are an acute toxic response and may not necessarily indicate a preneoplastic change. 相似文献
13.
14.
Jolinda LD Schram Joost Oude Groeniger Merel Schuring Karin I Proper Sandra H van Oostrom Suzan JW Robroek Alex Burdorf 《Scandinavian journal of work, environment & health》2021,47(2):127
Objective:Using a novel mediation method that presents unbiased results even in the presence of exposure–mediator interactions, this study estimated the extent to which working conditions and health behaviors contribute to educational inequalities in self-rated health in the workforce.Methods:Respondents of the longitudinal Survey of Health, Ageing, and Retirement in Europe (SHARE) in 16 countries were selected, aged 50–64 years, in paid employment at baseline and with information on education and self-rated health (N=15 028). Education, health behaviors [including body mass index (BMI)] and working conditions were measured at baseline and self-rated health at baseline and two-year follow-up. Causal mediation analysis with inverse odds weighting was used to estimate the total effect of education on self-rated health, decomposed into a natural direct effect (NDE) and natural indirect effect (NIE).Results:Lower educated workers were more likely to perceive their health as poor than higher educated workers [relative risk (RR) 1.48, 95% confidence interval (CI) 1.37–1.60]. They were also more likely to have unfavorable working conditions and unhealthy behaviors, except for alcohol consumption. When all working conditions were included, the remaining NDE was RR 1.30 (95% CI 1.15–1.44). When BMI and health behaviors were included, the remaining NDE was RR 1.40 (95% CI 1.27–1.54). Working conditions explained 38% and health behaviors and BMI explained 16% of educational inequalities in health. Including all mediators explained 64% of educational inequalities in self-rated health.Conclusions:Working conditions and health behaviors explain over half of the educational inequalities in self-rated health. To reduce health inequalities, improving working conditions seems to be more important than introducing health promotion programs in the workforce. 相似文献
15.
Lee BJ Ryu SG Choi HG Kim CK Parrott KA Ayres JW Sack RL 《Archives of pharmacal research》1997,20(6):555-559
The three different batches of an oral sustained release melatonin (MT) delivery system were prepared by aqueous-based fluid-bed coating of the sugar spheres for the evaluation ofin vitro release characteristics and plasma concentration profiles in human subjects. The MT contents in 20% coated sugar spheres of three batches (B1, B2 and B3) were 3.3+/-0.08, 2.4+/-0.1 and 2.5+/-0.13 mg per gram of coated sugar spheres, respectively. The release profiles of three different batches had a very similar fashion. However, the release half-lives (T(50%)) of MT from B1, B2 and B3 was 3.70+/-0.2, 5.2+/-0.2 and 4.9+/-0.07h, respectively. Plasma concentration profiles of sustained release 0.2mg melatonin-loaded sugar spheres containing 10% immediate release melatonin in gelatin capsules (B1 and B2) were then evaluated in human subjects. Thein vivo plasma concentration profiles of the two batches (B1 and B2) were very similar each other and located between the physiological endogenous ranges. The time to reach the peak concentration (T(max)) was more advanced in case of B1 when compared to B2. However, there was no statistically significant difference in the maximum concentration (C(max)) and the area under the curve (AUC) between B1 and B2. The AUC of melatonin-loaded sugar spheres containing 10% and 20% immediate release MT in human subjects had a good linearity between dose and AUC, regardless of the fraction of immediate release MT, indicating the first order elimination process of MT within these doses. The current oral sustained release MT delivery system may be utilized to treat circadian rhythm disorders if it is proven to be more clinically useful when compared to immediate release MT. 相似文献
16.
We describe the use of the 40-item Threat index (TI) with family members (N = 206) of surgical patients who also completed Templer's (1970) Death Anxiety Scale, the Death-of-Self and Dying-of-Self subscales of the Collett-Lester (1969) Fear of Death Scale, and the Death Acceptance subscale of Reker and Peacock's (1992) Life Attitude Profile-Revised. Word sets from the 40-item TI that are part of the 25- and 7-item versions of the TI produced strong alphas and correlatians to their parent instrument. Regression analyses indicated that selftideal-self scores and previous experience as a hospital patient were significant associated with TI scores. We conclude that if the time available for completion and scoring of the TI is limited, the shorter versions can be used, although their alpha strengths are slightly lower than that of the full TI and the respondent's age influences the scores. 相似文献
17.
18.
Ayres P 《Hospital medicine (London, England : 1998)》1999,60(7):505-508
The concept of clinical governance was first introduced to the NHS in late 1997. Since then, it has become a commonly used term, but there is still a great deal of uncertainty about what it means and how it should be implemented. This paper places clinical governance in the context of previous quality initiatives, and considers the roles of both managers and clinicians. 相似文献
19.
20.
This short communication describes the establishment of a trial and demonstration facility for new products, technologies, methods and procedures in an acute-care hospital ward at Concord Hospital in Sydney, Australia. The importance of innovation for all businesses, including hospitals, is discussed; and, why a project like the Model Ward can promote innovation as part of the corporate culture. The Model Ward development, implementation and its benefits are reported on and discussed. 相似文献