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   2286篇
  免费   145篇
  国内免费   13篇
耳鼻咽喉   7篇
儿科学   47篇
妇产科学   43篇
基础医学   334篇
口腔科学   120篇
临床医学   264篇
内科学   388篇
皮肤病学   24篇
神经病学   130篇
特种医学   109篇
外科学   307篇
综合类   86篇
现状与发展   1篇
一般理论   3篇
预防医学   334篇
眼科学   33篇
药学   120篇
中国医学   1篇
肿瘤学   93篇
  2023年   12篇
  2022年   13篇
  2021年   33篇
  2020年   26篇
  2019年   42篇
  2018年   40篇
  2017年   26篇
  2016年   44篇
  2015年   42篇
  2014年   59篇
  2013年   65篇
  2012年   85篇
  2011年   87篇
  2010年   49篇
  2009年   68篇
  2008年   97篇
  2007年   137篇
  2006年   105篇
  2005年   93篇
  2004年   88篇
  2003年   84篇
  2002年   63篇
  2001年   62篇
  2000年   88篇
  1999年   68篇
  1998年   49篇
  1997年   66篇
  1996年   49篇
  1995年   49篇
  1994年   38篇
  1993年   38篇
  1992年   50篇
  1991年   53篇
  1990年   57篇
  1989年   47篇
  1988年   46篇
  1987年   55篇
  1986年   34篇
  1985年   27篇
  1984年   31篇
  1983年   26篇
  1982年   16篇
  1980年   9篇
  1979年   16篇
  1978年   10篇
  1975年   9篇
  1974年   9篇
  1973年   10篇
  1971年   9篇
  1970年   10篇
排序方式: 共有2444条查询结果,搜索用时 15 毫秒
1.
2.
3.
4.
Neuronal activities following olfactory bulb electrical stimulation were examined before and after administration of dopamine and dopamine antagonist in the rat olfactory tubercle. The inhibitory response to olfactory bulb stimulation was attenuated by systemic haloperidol administration, but the excitatory response to olfactory bulb stimulation rarely was modulated. Topical application of dopamine by iontophoresis extended the duration of inhibition in 56% of the neurons sampled and diminished it in 25%; the excitatory response was modulated in 42% of neurons, most of which were attenuated. These findings suggest that dopamine in the olfactory tubercle could be involved in modulations of neuronal activities related to olfactory transduction.  相似文献   
5.
Cancer of the maxillary sinus treated with surgery and/or radiation therapy   总被引:1,自引:0,他引:1  
This is an analysis of 37 previously untreated patients with squamous cell carcinoma of the maxillary sinus treated with curative intent at the University of Florida from January 1966 through January 1984. All patients were followed for at least two years and 86 per cent (32/27) were followed for a minimum of five years. Patients were treated for cure with radiation therapy alone (25), surgery alone (1), or surgery and preoperative (6) or postoperative (5) radiation therapy. This study presents the results of treatment and the incidence of treatment-related complications in this group of patients.  相似文献   
6.
7.
For 3 months in 1969 a family in the United States that included a pregnant mother consumed pork containing methylmercury. Children, aged 20, 13, and 8 years and a neonate, developed severe neurological signs. Twenty-two years later, the 2 oldest had cortical blindness or constricted visual fields, diminished hand proprioception, choreoathetosis, and atentional deficits. Magnetic resonance images showed tissue loss in the calcarine and parietal cortices and cerebellar folia. The youngest had quadriplegia, blindness, and severe mental retradation until their deaths. The brain of the 8-year-old who died at age 30 showed cortical atrophy, neuronal loss, and gliosis, most pronounced in the paracentral and parietooccipital regions. The total mercury level in formalin-fixed, left occipital cortex was 1,974 ng/gm as measured by atomic absorption. Regional brain mercury levels correlated with extent of brain damage. A control patient had 38.5 ng of mercury/gm in the occipital cortex. Systemic organs in the patient and a control subject had comparable mercury levels. In mercury-intoxicated rats, we found that only 5 to 10% of total brain mercury was lost by formalin fixation. Brain inorganic mercury in the patient ranged from 82 to 100%. Since inorganic mercury crosses the blood-brain barrier poorly, biotransformation of methyl to inorganic mercury may have occurred after methylmercury crossed the blood-brain barrier, accounting for its persistence in brain and causing part of the brain damage.  相似文献   
8.
报道了氯仿重结晶的棉酚的化学性质,样品在不同温度下干燥恒重后,经熔点、薄层层析、紫外光谱、红外光谱、X-射线衍射、热重量分析、元素(C,H,Cl)分析及棉酚合量测定等一系列的分析,确证了在60℃以下棉酚与氯仿成溶剂化物(solvate)。随着干燥温度的升高或在室温长时间的贮存,此现象逐渐消失,100℃真空干燥恒重后成为纯棉酚。  相似文献   
9.
10.
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