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   153709篇
  免费   10117篇
  国内免费   777篇
耳鼻咽喉   1408篇
儿科学   3903篇
妇产科学   2779篇
基础医学   20675篇
口腔科学   3457篇
临床医学   14760篇
内科学   33103篇
皮肤病学   2880篇
神经病学   14966篇
特种医学   6137篇
外国民族医学   6篇
外科学   23078篇
综合类   1906篇
现状与发展   2篇
一般理论   139篇
预防医学   11067篇
眼科学   3215篇
药学   10518篇
  2篇
中国医学   245篇
肿瘤学   10357篇
  2023年   825篇
  2022年   1244篇
  2021年   2835篇
  2020年   1966篇
  2019年   2837篇
  2018年   3437篇
  2017年   2682篇
  2016年   3067篇
  2015年   3525篇
  2014年   5052篇
  2013年   6816篇
  2012年   10542篇
  2011年   11164篇
  2010年   6363篇
  2009年   6060篇
  2008年   10227篇
  2007年   10906篇
  2006年   10375篇
  2005年   10628篇
  2004年   10030篇
  2003年   9517篇
  2002年   8937篇
  2001年   1508篇
  2000年   1132篇
  1999年   1616篇
  1998年   2114篇
  1997年   1650篇
  1996年   1425篇
  1995年   1294篇
  1994年   1148篇
  1993年   1118篇
  1992年   784篇
  1991年   792篇
  1990年   617篇
  1989年   598篇
  1988年   562篇
  1987年   574篇
  1986年   511篇
  1985年   537篇
  1984年   641篇
  1983年   565篇
  1982年   759篇
  1981年   701篇
  1980年   602篇
  1979年   370篇
  1978年   380篇
  1977年   409篇
  1976年   343篇
  1975年   298篇
  1974年   250篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
21.
The “restricted areas” provisions of the Northern Territory Liquor Act constitute a preventative policy aimed at reducing the effects of alcohol abuse, particularly on Aboriginal communities. Under the provisions, communities can apply to be declared “dry” or semi-restricted with respect to liquor. Since their inception in 1979, the provisions have given rise to continuing controversy. This paper addresses some of the issues associated with the controversy. Patterns of alcohol consumption on “dry”, semi-restricted and unrestricted communities are compared, and the incidence of apprehension for public drunkenness before and after restricted area declarations is examined. The paper also discusses the provisions under which vehicles implicated in acts of illicit “grog-running” are forfeited to the NT Government. It is concluded that the restricted area provisions are associated with reduced levels of alcohol consumption and apprehensions for drunkenness, and are therefore beneficial in outcome. However, it is also argued that at present the provisions are flawed in that, while some aspects serve to promote community control over alcohol consumption, other elements have the effect of undermining community control and responsibility.  相似文献   
22.
23.
We reviewed the results of all pediatric patients undergoing intracranial pressure (ICP) monitoring in a 2-year period at our institution. The outcome of patients suffering hypoxia or ischemic injuries (HII) is compared to those suffering non-hypoxic or non-ischemic injuries (NHII). Thirty-four patients had ICP monitors placed during the study period. Inconplete patient information led to the exclusion of 5 patients. An additional 5 patients were excluded because no measures to control ICP were taken after the monitor was placed. Twenty-four patients required treatment for raised ICP (hyperventilation, 24; mannitol, 19; barbiturate coma, 6). Admission Glasgow Coma Score in patients suffering HII (median score 5) and NHII (median score 6) were not significantly different (Mann-Whitney U Test). Only 2 of 8 patients with HII were near-drowning vietims. The remaining 6 had HII from other causes (5 survivors of various forms of asphyxia and 1 of cardiac arrest). All 8 patients had poor outcomes (1 severely disabled; 7 died). The 16 patients with NHII had a variety of diagnoses (6 trauma, 5 encephalitis, 4 bacterial meningitis, 1 diabetic ketoacidosis). Among these, 6 had good outcomes and 10 poor outcomes (2 severely disabled, 2 vegetative, and 6 died). The difference in outcome between patients with NHII and HII is significant at P=0.059 (Fischer Exact test). Patients with NHII may benefit from ICP monitoring. Patients with HII from near-drowning and other causes did not appear to benefit from ICP monitoring and interventions directed at controlling ICP.  相似文献   
24.
25.
26.
27.
Liquid-crystalline main-chain polyesters with polystyrene side chains of different length and number per main chain were synthesized using aromatic hydroxyfunctional polystyrene (PS) macromonomers, terephthalic acid derivatives and tert-butylhydroquinone as co-diol. The molecular weight of the polystyrene side chain was varied in the range from 1000 to 20000. The influence of this novel type of substituent on the solubility, thermal behaviour and miscibility with PS as a flexible matrix polymer is discussed. The properties of the new compounds are compared to those of the respective homopolyester. The graft copolyesters are, depending on the characteristics of the polymeric substituent, soluble in common organic solvents and their thermal transition points are lowered compared to the homopolyester. Compared to blends of the homopolyester, the improvement of miscibility of the polymer-substituted rigid rods with PS as an example for a flexible matrix polymer can be valued as a step to molecular reinforcement.  相似文献   
28.
29.
30.
The functional significance of the pars tuberalis (PT) of the mammalian adenohypophysis has remained an enigma (1, 2). One view of its function is that it acts as an auxiliary gland to support the endocrine role of the pars distalis (PD) (2), as it has been shown to contain immunocytochemically identifiable thyrotrophs and gonadotrophs (1). Many of the cells of the PT are, however, ultrastructurally unique suggesting an independent function for this tissue. Our recent demonstration that the PT of the rat is a major binding site for the ligand iodomelatonin lends further support to this idea (3). We have utilized the highly specific ligand [125l]melatonin, and have demonstrated that it binds exclusively, with very high affinity, to the PT but not the PD of the adult sheep adenohypophysis. These findings support the conclusion that the PT has a distinct role in relation to melatonin action and seasonal reproduction.  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