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   2363282篇
  免费   182232篇
  国内免费   7771篇
耳鼻咽喉   32007篇
儿科学   77877篇
妇产科学   66712篇
基础医学   333766篇
口腔科学   66110篇
临床医学   208728篇
内科学   471299篇
皮肤病学   53675篇
神经病学   190279篇
特种医学   94753篇
外国民族医学   620篇
外科学   366644篇
综合类   52812篇
现状与发展   3篇
一般理论   694篇
预防医学   184437篇
眼科学   52933篇
药学   172562篇
  6篇
中国医学   4269篇
肿瘤学   123099篇
  2018年   23060篇
  2016年   20979篇
  2015年   23720篇
  2014年   33069篇
  2013年   50002篇
  2012年   64274篇
  2011年   68905篇
  2010年   42096篇
  2009年   40567篇
  2008年   65313篇
  2007年   70387篇
  2006年   71756篇
  2005年   69958篇
  2004年   67155篇
  2003年   65218篇
  2002年   63023篇
  2001年   108287篇
  2000年   111443篇
  1999年   93980篇
  1998年   28068篇
  1997年   25134篇
  1996年   25990篇
  1995年   25451篇
  1994年   24000篇
  1993年   22348篇
  1992年   77534篇
  1991年   75972篇
  1990年   74003篇
  1989年   70950篇
  1988年   66139篇
  1987年   64831篇
  1986年   61694篇
  1985年   59195篇
  1984年   44822篇
  1983年   38321篇
  1982年   23669篇
  1981年   21137篇
  1980年   19827篇
  1979年   41531篇
  1978年   29749篇
  1977年   25351篇
  1976年   23601篇
  1975年   25367篇
  1974年   29880篇
  1973年   28674篇
  1972年   26875篇
  1971年   24894篇
  1970年   22944篇
  1969年   21889篇
  1968年   20574篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
993.
A detailed examination of quantitative relationships of pharmacological action with plasma and tissue concentrations of indomethacin has been undertaken in the rat, after single oral administration of two sustained release preparations. In this study, drug was assayed by high performance liquid chromatography, whereas antiinflammatory response was assessed through the carrageenin-induced edema test. Significant linear correlations (p less than 0.001) were found between logarithmically transformed percent inhibition of edema and logarithmically transformed plasma, as well as tissue levels of indomethacin. However, the lack of significance for partial correlation regarding tissue concentration, contrary to plasma concentration, suggests that pharmacological response is more closely related to the latter, indicating that antidematous effect is mediated via the circulating drug rather than a local action in target tissues. This assumption is further discussed from the equivalence point of view. The relevance of this type of study in the case of topical administration of indomethacin is addressed as well. Taking into account the predictive value of the rat paw edema test for clinical efficacy, relationships similar to those observed are to be expected in man. The high correlation existing between plasma concentration of indomethacin and its pharmacological effect justifies the development and use of sustained release preparations in order to improve the outcome of treatment with this nonsteroidal antiinflammatory drug.  相似文献   
994.
The contributors propose a set of newly performed hygienic studies in the widely developed technologies of electrotype, expound a complex of the hazardous occupational factors commonly encountered in modern galvanoplastics, contamination of the equipment, overalls and the skin with the metallic compounds contained in the galvanic electrolytes. Shops with non-isolated electrotype lines were characterized by the most unfavourable labour conditions.  相似文献   
995.
The following pages try to offer some ways of arguing against pesimism in our health administration culture. In fact, the review of a wide range of feasible reforms of our health system undertaken in this paper gives some clues for a better implementation of the a priori advantages of public health systems. These advantages are not achieved today because of some dysfunctionalities of daily management. To rationalize resources distribution, to evaluate the results, to eliminate unnecessary administrative control, to coordinate responsibility and budgeting centers, to introduce free choice as a response to public demand, and to simulate marketing by private production of public services are elements suggested in this paper to improve public health services management.  相似文献   
996.
An area analysis is presented of deaths in Auckland that were ostensibly avoidable, by appropriate medical intervention and treatment. Mortality data from the National Health Statistics Centre for the period 1977-85 were used in the analysis. The definition of an avoidable death was based on the International Classification of Diseases (ICD) code using established criteria. Eight percent of deaths of people under 65 years of age met the criteria. The basic spatial entity for the analysis is the census area unit and maps of Auckland are presented to show the distribution of avoidable mortality. It is found that there are significant and consistent spatial variations. Three areas with avoidable mortality that is generally higher than elsewhere are apparent: in south Auckland; to the north-west of the central urban sector centered on Grey Lynn; and in the eastern parts of the central sector from Glenn Innes to Onehunga.  相似文献   
997.
998.
999.
The authors describe a method for silicone intubation of a single patent canaliculus associated with a nasolacrimal duct obstruction. Although bicanalicular intubation is always preferable when possible, unicanalicular stenting is necessary when only one canaliculus is patent. A chief advantage of this technique is that the lacrimal stent is inaccessible to the child and thus cannot be accidentally pulled out.  相似文献   
1000.
D J Harris  G O Waring  L L Burk 《Ophthalmology》1989,96(11):1597-1607
After penetrating keratoplasty in 52 eyes, keratography refraction and keratometry were used to select appropriate interrupted sutures for removal in order to reduce astigmatism. All eyes had one continuous and either 12 or 16 interrupted nylon sutures. The keratographs were examined retrospectively and separated into six groups on the basis of similar mire patterns. The removal of single sutures associated with three of these patterns reduced astigmatism by the following average amounts: symmetrical oval pattern, 0.44 diopters (D); D-shaped oval pattern, 2.07 D; and focal indentation pattern, 6.60 D. The other three patterns--mildly disrupted mires, incomplete mires, and uninterpretable mires--did not allow quantification of results. Examples of these keratographic patterns are presented and recommendations are made for their use in the management of astigmatism following penetrating keratoplasty.  相似文献   
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