全文获取类型
收费全文 | 6837篇 |
免费 | 717篇 |
国内免费 | 30篇 |
专业分类
耳鼻咽喉 | 65篇 |
儿科学 | 332篇 |
妇产科学 | 83篇 |
基础医学 | 806篇 |
口腔科学 | 164篇 |
临床医学 | 682篇 |
内科学 | 1307篇 |
皮肤病学 | 368篇 |
神经病学 | 457篇 |
特种医学 | 470篇 |
外科学 | 991篇 |
综合类 | 178篇 |
一般理论 | 8篇 |
预防医学 | 518篇 |
眼科学 | 44篇 |
药学 | 451篇 |
中国医学 | 3篇 |
肿瘤学 | 657篇 |
出版年
2021年 | 72篇 |
2019年 | 78篇 |
2018年 | 94篇 |
2017年 | 62篇 |
2016年 | 78篇 |
2015年 | 84篇 |
2014年 | 106篇 |
2013年 | 144篇 |
2012年 | 197篇 |
2011年 | 201篇 |
2010年 | 163篇 |
2009年 | 142篇 |
2008年 | 228篇 |
2007年 | 253篇 |
2006年 | 262篇 |
2005年 | 245篇 |
2004年 | 227篇 |
2003年 | 243篇 |
2002年 | 192篇 |
2001年 | 207篇 |
2000年 | 226篇 |
1999年 | 213篇 |
1998年 | 128篇 |
1997年 | 141篇 |
1996年 | 155篇 |
1995年 | 123篇 |
1994年 | 93篇 |
1993年 | 92篇 |
1992年 | 161篇 |
1991年 | 192篇 |
1990年 | 181篇 |
1989年 | 174篇 |
1988年 | 212篇 |
1987年 | 186篇 |
1986年 | 159篇 |
1985年 | 199篇 |
1984年 | 114篇 |
1983年 | 123篇 |
1982年 | 74篇 |
1981年 | 71篇 |
1980年 | 62篇 |
1979年 | 109篇 |
1978年 | 101篇 |
1977年 | 82篇 |
1976年 | 79篇 |
1975年 | 72篇 |
1974年 | 93篇 |
1973年 | 100篇 |
1972年 | 72篇 |
1971年 | 72篇 |
排序方式: 共有7584条查询结果,搜索用时 0 毫秒
141.
BACKGROUND: House dust mite (HDM) allergy is closely linked to the expression of asthma and other allergic diseases. Understanding factors influencing variation in allergen may help in controlling allergic disease. The objective of this study was to investigate the effects of seasonal changes in climate, type of bed used in very early childhood and anti-mite interventions on HDM allergen concentration. METHODS: Participants were enrolled in a randomized-controlled trial of HDM avoidance. Der p 1 was measured in dust samples from children's beds on 13 occasions, from birth to age 5 years, between 1997 and 2004. Bed types were categorized as bassinette, cot or bed. The effects of study month, type of bed and intervention group on HDM allergen concentration were estimated by multiple linear regression. The relation between climatic variables and HDM allergen concentration was investigated using a polynomial distributed lag model. RESULTS: House dust mite allergen concentrations were initially low in cots and bassinettes in 1997/1998, peaked in bassinettes and beds between 1999 and 2001 and then slowly declined during the period 2002/2004. Seasonal fluctuations occurred with minima in summer and two- to threefold higher maxima during late autumn. Allergen peaks were correlated with relative humidity peaks 2 months previously. Seasonal changes in allergen were not affected by the HDM avoidance intervention. CONCLUSIONS: House dust mite allergen concentrations in Sydney beds fluctuate approximately two- to threefold on an annual cycle, partly determined by relative humidity, with peaks in late autumn and minima in summer. Fluctuations of this magnitude might be sufficient to influence asthma symptoms. 相似文献
142.
Marks B 《The Journal of nursing education》2007,46(2):70-74
The demographic profile of students in nursing schools is changing in relation to many different cultural backgrounds. Despite the potential for students with disabilities to enrich the nursing profession, nurse educators may be perpetuating historical attitudes, values, and practices that exclude students with disabilities from gaining admission or identifying themselves as people with disabilities. Educators in nursing schools continue to ask whether people with disabilities have a place in the nursing profession, while the more salient question is, "When will people with disabilities have a place in the nursing profession?" More important, as we create environments that welcome students with disabilities into the nursing profession, how does the quality of nursing care improve and become more appropriate for people with different cultural experiences? The purpose of this article is to present the value of recruiting students with disabilities into nursing schools in, order to enhance culturally competent nursing care. 相似文献
143.
144.
DTS Chang IA Thyer D Hayne DJ Katz 《Annals of the Royal College of Surgeons of England》2014,96(6):e23-e25
Australia has a large migrant population with variable fluency in English. Interpreting services help ensure that healthcare services are delivered appropriately to these populations. However, the use of professional interpreters in hospitals is expensive. There are also issues with service availability and convenience. Mobile devices containing software with translating abilities have promising potential to improve communication between patients and hospital staff as an adjunct to professional interpreters. It is highly convenient and inexpensive. There are concerns about the accuracy of the interpretation done with such software and more research needs to be carried out to support or allay these concerns. For now, clinically important and medicolegal related interpretation should be undertaken by professional interpreters whereas less crucial tasks may be performed with the help of interpreting software on mobile devices. 相似文献
145.
146.
147.
Marks J. H. Salem J. F. Adams P. Sun T. Kunkel E. Schoonyoung H. Agarwal S. 《Techniques in coloproctology》2021,25(6):721-726
Techniques in Coloproctology - The technical difficulty and steep learning curve of transanal total mesorectal excision (taTME) has limited widespread adoption. The single-port (SP) daVinci robot... 相似文献
148.
Michael Marks Pere Millat-Martinez Dan Ouchi Chrissy h Roberts Andrea Alemany Marc Corbacho-Monné Maria Ubals Aurelio Tobias Cristian Tebé Ester Ballana Quique Bassat Bàrbara Baro Martí Vall-Mayans Camila G-Beiras Nuria Prat Jordi Ara Bonaventura Clotet Oriol Mitjà 《The Lancet infectious diseases》2021,21(5):629-636
149.
150.
We have developed a general quenched-flow approach to study platelet function as early as 0.3 seconds after stimulation. Phosphorylation of 20- and 40-kd proteins has been analyzed during the first five seconds of platelet response to thrombin from 0.1 to 5.0 U/mL and compared with the progress of aggregation and serotonin secretion. The onset time for aggregation and phosphorylation of both proteins was less than one second, although with lowest (less than 0.5 U/mL) thrombin levels, a lag of up to 0.6 seconds occurred before 40K phosphorylation increased. The thrombin sensitivity of aggregation and 20K phosphorylation was approximately twice that of 40K phosphorylation, with Ka values of 0.51 and 0.53 v 1.10 U/mL, respectively. External calcium was necessary for maximal 20K phosphorylation, since EDTA inhibited this by 30%. The 40K phosphorylation was not affected by EDTA. Platelet activation by thrombin thus induced biochemical changes well before one second. The quenched-flow approach may help to reveal relationships between phospholipase activation, calcium fluxes, and protein phosphorylation during these early periods of platelet function. 相似文献