首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   1035篇
  免费   74篇
  国内免费   8篇
耳鼻咽喉   3篇
儿科学   14篇
妇产科学   11篇
基础医学   179篇
口腔科学   6篇
临床医学   107篇
内科学   219篇
皮肤病学   8篇
神经病学   108篇
特种医学   29篇
外国民族医学   22篇
外科学   98篇
综合类   8篇
预防医学   72篇
眼科学   18篇
药学   99篇
中国医学   10篇
肿瘤学   106篇
  2023年   9篇
  2022年   39篇
  2021年   45篇
  2020年   14篇
  2019年   26篇
  2018年   41篇
  2017年   22篇
  2016年   32篇
  2015年   29篇
  2014年   42篇
  2013年   41篇
  2012年   73篇
  2011年   70篇
  2010年   39篇
  2009年   38篇
  2008年   74篇
  2007年   69篇
  2006年   60篇
  2005年   51篇
  2004年   65篇
  2003年   55篇
  2002年   65篇
  2001年   12篇
  2000年   12篇
  1999年   13篇
  1998年   6篇
  1997年   9篇
  1996年   9篇
  1995年   6篇
  1993年   3篇
  1992年   3篇
  1991年   2篇
  1990年   2篇
  1987年   1篇
  1985年   2篇
  1984年   2篇
  1982年   3篇
  1981年   1篇
  1980年   2篇
  1978年   1篇
  1976年   1篇
  1974年   3篇
  1972年   2篇
  1971年   2篇
  1970年   3篇
  1969年   3篇
  1968年   2篇
  1967年   3篇
  1966年   6篇
  1965年   1篇
排序方式: 共有1117条查询结果,搜索用时 15 毫秒
991.
OBJECTIVE: To investigate Australian adults' awareness of the ultraviolet (UV) indexes forecast in the media, and whether these UV forecasts influence their behaviour in the sun. METHODS: A self-administered questionnaire was used on two occasions in 1997 to ask about knowledge of UV indexes shown in the media and about possible influence on outdoor behaviour. SETTING AND PARTICIPANTS: Participants were 977 residents (423 men; 554 women) of Nambour originally randomly selected in 1986 from the electoral roll, who have been followed up subsequently. RESULTS: The majority of people--92% of men and 86% of women--reported having seen or heard the UV indexes forecast during summer. Of these, significantly fewer men (107; 28%) than women (209; 46%) reported that their outdoor behaviour was influenced by knowledge of the forecast (p = 0.001). Neither age nor skin type, nor history of sunburns or skin cancer, affected knowledge of UV forecasts or their influence on behaviour. CONCLUSIONS AND IMPLICATIONS: Although most people are aware of the forecasts of UV indexes in the media, the majority do not take them into account in their outdoor behaviour. Compared with women, men were more aware of, but less influenced by, forecasts of UV indexes. Better communication of the implications of the UV indexes is needed, particularly to men, if they are to adapt their outdoor behaviour to improve their sun protection.  相似文献   
992.
993.
994.
· Background: Acute follicular conjunctivitis is a clinical diagnosis common to multiple etiologies, of which chlamydial infection requires specific antibiotic treatment. · Purpose: This prospective study was designed to evaluate Chlamydia trachomatis as the cause of acute follicular conjunctivitis by two sensitive tests: direct enzyme-linked immunosorbent assay (ELISA) and polymerase chain reaction (PCR). · Methods: Conjunctival scrapings from patients presented with untreated acute follicular conjunctivitis were examined by ELISA and PCR, and patients were followed up for prolongation of the disease course. · Results: All 36 consecutive patients presented with acute follicular conjunctivitis were negative for Chlamydia trachomatis by ELISA and PCR. None of the patients had a prolonged course of more than 4 weeks or required treatment with systemic antibiotics as would be expected from chlamydial infection. · Conclusions: Chlamydia trachomatis was probably not responsible for the acute follicular conjunctivitis in this series, and ELISA and PCR may not be cost effective for evaluation of acute follicular conjunctivitis due to chlamydial infection. Further evaluation of the cost effectiveness of these tests is required in chronic follicular conjunctivitis. Received: 19 August 1998 Revised version received: 26 October 1998 Accepted: 2 November 1998  相似文献   
995.
Characterization of Powassan viruses from Far Eastern Russia   总被引:1,自引:0,他引:1  
We report the isolation and detailed characterization of the novel strain, Partizansk/2006, of Powassan virus (POWV) from a human case of infection, which occurred in Primorsky krai, Russia, in 2006. Comparative complete genome sequence analysis of the Far Eastern strains Spassk-9 (1975), Nadezdinsk-1991 and Partizansk/2006 of POWV revealed that these strains are 99.8% similar to the LB strain, which was isolated in Canada in 1958. Phylogenetic analysis of 5′ UTR sequences of five other strains of POWV isolated from 1972 to 1986 in Primorsky krai produced similar results. Presumably, Far Eastern POWV has common putative ancestor with LB strain POWV from North America, and the time of divergence of these POWVs is relatively short. We conclude that POWV has become endemic in Far Eastern Russia.  相似文献   
996.
997.
Receptors for extracellular ATP (both ionotropic and metabotropic) are widely expressed in the CNS both in neurones and glia. ATP can modulate neuronal activity in many parts of the brain and contributes to the central nervous control of several physiological functions. Here we show that during the systemic inflammatory response the extracellular concentrations of ATP increase in the anterior hypothalamus and this has a profound effect on the development of the thermoregulatory febrile response. In conscious rabbits we measured ATP release in real time with novel amperometric biosensors and monitored a marked increase in the concentration of ATP (4.0 ± 0.7 μ m ) in the anterior hypothalamus in response to intravenous injection of bacterial endotoxin – lipopolysaccharide (LPS). No ATP release was observed in the posterior hypothalamus. The release of ATP coincided with the development of the initial phase of the febrile response, starting 18 ± 2 min and reaching its peak 45 ± 2 min after LPS injection. Application of the ATP receptor antagonists pyridoxal-5'-phosphate-6-azophenyl-2',4'-disulphonic acid, Brilliant Blue G or periodate oxidized ATP dialdehyde to the site of ATP release in the anterior hypothalamus markedly augmented and prolonged the febrile response. These data indicate that during the development of the systemic inflammation, ATP is released in the anterior hypothalamus to limit the magnitude and duration of fever. This release may also have a profound effect on the hypothalamic control of other physiological functions in which ATP and related purines have been implicated to play modulatory roles, such as food intake, hormone secretion, cardiovascular activity and sleep.  相似文献   
998.
999.
The results of a decay data evaluation are presented for 233Pa (beta-) decay to nuclear levels in 233U. These evaluated data have been obtained within the Decay Data Evaluation Project using information published up to 2005.  相似文献   
1000.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号