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   1603082篇
  免费   131665篇
  国内免费   2586篇
耳鼻咽喉   21665篇
儿科学   52966篇
妇产科学   46251篇
基础医学   227951篇
口腔科学   47215篇
临床医学   141105篇
内科学   314990篇
皮肤病学   34111篇
神经病学   130200篇
特种医学   64767篇
外国民族医学   474篇
外科学   243959篇
综合类   39742篇
现状与发展   3篇
一般理论   547篇
预防医学   123043篇
眼科学   36565篇
药学   121404篇
  3篇
中国医学   2976篇
肿瘤学   87396篇
  2018年   14805篇
  2016年   12912篇
  2015年   15054篇
  2014年   20671篇
  2013年   31391篇
  2012年   42605篇
  2011年   44839篇
  2010年   26374篇
  2009年   25350篇
  2008年   43070篇
  2007年   45314篇
  2006年   46131篇
  2005年   44742篇
  2004年   44163篇
  2003年   42248篇
  2002年   41358篇
  2001年   75716篇
  2000年   78370篇
  1999年   66416篇
  1998年   17748篇
  1997年   16344篇
  1996年   16323篇
  1995年   16029篇
  1994年   15077篇
  1993年   14226篇
  1992年   55455篇
  1991年   53805篇
  1990年   52595篇
  1989年   50862篇
  1988年   47246篇
  1987年   46590篇
  1986年   44300篇
  1985年   42863篇
  1984年   32053篇
  1983年   27588篇
  1982年   16151篇
  1981年   14449篇
  1980年   13572篇
  1979年   30477篇
  1978年   21083篇
  1977年   17774篇
  1976年   16704篇
  1975年   17578篇
  1974年   21496篇
  1973年   20685篇
  1972年   18865篇
  1971年   17778篇
  1970年   16291篇
  1969年   15276篇
  1968年   13958篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
92.
The prevalence of heavy alcohol consumption is a major problem of increasing proportions throughout the world. Although alcohol sensitizing drugs and more recently serotonin uptake inhibitors are drug interventions with some following, their long term beneficial consequences have yet to be demonstrated. In recent years, we have demonstrated that manipulating activity in the renin-angiotensin system will dramatically alter voluntary alcohol consumption in rats. Based on these findings, the present study evaluated the ability of a class of drugs known as the angiotensin converting enzyme inhibitors to reduce voluntary alcohol drinking in laboratory animals. These drugs prevent the conversion of angiotensin I to angiotensin II. They have been licensed for use in Europe and North America and are indicated in the treatment of hypertension. Our experiments showed that both captopril (Capoten, Squibb) and enalapril (Vasotec, Merck Sharpe & Dohme) can reduce alcohol drinking in both normotensive and hypertensive animals regardless of whether the pattern of intake is in a bout or of a less exaggerated nature. Furthermore, this change in alcohol intake can occur without concomitant changes in blood pressure, plasma renin activity, overall fluid balance, or the distribution and metabolism of alcohol. Taken together these findings suggest that the angiotensin converting enzyme inhibitors should be evaluated in a clinical setting for they may prove to be a useful new treatment or treatment adjunct for alcohol abuse in humans.  相似文献   
93.
It has long been noted that tetanus is rare in leprosy patients. Five cases of tetanus are reported in leprosy patients in Addis Ababa, Ethiopia. Although natural immunity to tetanus occurs and this appears to be higher in leprosy patients than in the general population, it is not completely protective. Further research on the relationship between tetanus and leprosy is indicated. Although firm epidemiologic data are lacking, it is prudent to give leprosy patients at least one dose of tetanus toxoid.  相似文献   
94.
95.
The use of additional epidural sympathetic block during and after microvascular surgery in the lower extremities to prevent vasospasm is generally agreed on. However, a significant fall in the perfusion rate of the transplants was seen after application of bupivacaine (Marcain) via the epidural catheter. This effect has, to our knowledge, not been described before and is probably caused by the sympathectomy effect of this type of analgesia.  相似文献   
96.
97.
Neglected tears of the patellar tendon due to loss of active extension remain a difficult therapeutic endeavor. The goals in the approach to this diagnosis include restoration of both structural and functional integrity of the extensor mechanism. A procedure has been developed utilizing Z-shortening of the patellar tendon, Z-lengthening of the quadriceps tendon, and the semitendinosis gracilis as a biologic splint. This technique allows establishment of preoperative goals, including restoration of the muscle-tendon complex in its anatomic position, restoration of quadriceps function, preservation of vascularity of the reconstructed tendon, and splinting of the patellar tendon. This reconstruction allows early mobilization and rehabilitation.  相似文献   
98.
The present study demonstrates that alcohol-induced memory impairment can be attenuated by pretreatment with an oral tryptophan supplementation. These results provide support for the role of a brain serotonin deficit in this impairment and highlight the impact a dietary manipulation can have on a complex behavioral process.  相似文献   
99.
Summary. In this study, we have examined our records for the isolation of Candida tropicalis from clinical specimens of patients with heterogeneous clinical presentations during the past 5 years. We have found that this species ranks third among all yeasts in frequency of isolation from clinical specimens and that the trend of recovery from the specimens is rising over the years. The isolation rate of C. tropicalis was highest from urine specimens (36%) followed by respiratory specimens (22%). The frequency of isolation of C. tropicalis from vaginal specimens was relatively high (14%), however the trend was declining over the years. In general, the high recovery of Candida tropicalis from clinical specimens of patients with variable disease supports the views of this organism being a major pathogen.
Zusammenfassung. Die Studie basiert auf einer Durchsicht der Patientenarchive der letzten fünf Jahre auf die Isolationshäufigkeit von Candida tropicalis aus klinischen Untersuchungsmaterialien von Patienten mit unterschiedlichen klinischen Krankheitsbildern. Diese Hefeart war die dritthäufigste mit steigender Tendenz über die Jahre. Die Isolierungsrate von C. tropicalis war am höchsten aus Urin (36%), gefolgt von Respirationstrakt-Materialien (22%). Die Isolationshäufigkeit aus dem hinteren Scheidengewölbe war relativ hoch (14%), nahm jedoch mit den jahren ab. Allgemein unterstreicht die hohe Isolationsrate von C. tropicalis aus klinischen Untersuchungsmaterialien die ätiologische Bedeutung dieses Erregers.  相似文献   
100.
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