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   36251篇
  免费   2160篇
  国内免费   160篇
耳鼻咽喉   515篇
儿科学   851篇
妇产科学   667篇
基础医学   4320篇
口腔科学   670篇
临床医学   3499篇
内科学   8505篇
皮肤病学   420篇
神经病学   3421篇
特种医学   1487篇
外国民族医学   1篇
外科学   6379篇
综合类   225篇
一般理论   19篇
预防医学   2128篇
眼科学   511篇
药学   2066篇
中国医学   45篇
肿瘤学   2842篇
  2023年   211篇
  2022年   398篇
  2021年   903篇
  2020年   549篇
  2019年   889篇
  2018年   1113篇
  2017年   756篇
  2016年   784篇
  2015年   938篇
  2014年   1386篇
  2013年   1854篇
  2012年   2724篇
  2011年   2921篇
  2010年   1664篇
  2009年   1600篇
  2008年   2518篇
  2007年   2658篇
  2006年   2477篇
  2005年   2394篇
  2004年   2157篇
  2003年   2016篇
  2002年   1815篇
  2001年   293篇
  2000年   199篇
  1999年   260篇
  1998年   405篇
  1997年   323篇
  1996年   233篇
  1995年   229篇
  1994年   189篇
  1993年   177篇
  1992年   111篇
  1991年   120篇
  1990年   94篇
  1989年   93篇
  1988年   70篇
  1987年   64篇
  1986年   66篇
  1985年   77篇
  1984年   91篇
  1983年   94篇
  1982年   90篇
  1981年   84篇
  1980年   69篇
  1979年   42篇
  1978年   41篇
  1977年   36篇
  1976年   25篇
  1975年   30篇
  1974年   29篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
51.
52.
53.
54.
28 patients with a fracture of the distal end of the radius were treated by a T-plate osteosynthesis through the volar approach. There were 7 unstable distal metaphyseal fractures and 21 dislocated intra-articular fractures. 21 patients were investigated 6 months to 8 years after operation according to the scheme of Sarmiento. 17 patients had a good or excellent result, 4 patients a fair or poor result. 2 patients developed a Sudeck's dystrophy (Algodystrophy), one of them with a radial-ulnar bone bridge. The volar application of the plate is indicated for flexion and extension fractures. In cases with compression of the dorsal cortex a bone graft is indicated to improve a stable osteosynthesis. A conventional tomography on two views helps to diagnose exactly an intra-articular fracture and to decide whether to use a plate or pins and external fixation after open reduction. Remanipulation or an operation 2 weeks after trauma increases the risk of a Sudeck's dystrophy and leads to a poor result.  相似文献   
55.
Prospective study of phobic anxiety and risk of Parkinson's disease.   总被引:3,自引:0,他引:3  
Anxiety disorders are common in Parkinson's disease (PD). However, the risk of PD among people with anxiety has not been examined in a prospective cohort study. We examined this relation prospectively within the Health Professionals Follow-Up Study, a cohort of US male health professionals. In 1988, anxiety was assessed using the Crown-Crisp phobic anxiety index in 35,815 men without PD, stroke, or cancer at baseline. There were 189 incident cases of PD during 12 years of follow-up. After adjusting for age, smoking, and caffeine intake, the relative risk of PD among men with the highest level of anxiety (Crown-Crisp index scores of 4 and above) was 1.5 (95% CI = 1.0-2.1; P-trend = 0.01) compared to men with the lowest level of anxiety. This positive association persisted after excluding cases of PD with onset in the first 2 years of follow-up. Use of anxiolytic medication was also associated with an elevated risk of PD (RR= 1.6; 95% CI = 0.9-3.1), but adjusting for this potential confounder did not materially affect the association between anxiety and risk of PD. Our results suggest that anxiety is a risk factor for PD. Whether this association is causal or the result of shared underlying biology remains a question.  相似文献   
56.
A 66-year-old man with atrial fibrillation was referred soon after developing left lower limb and abdominal pain with rectal bleeding. An immediate flush aortogram showed embolic occlusion of the left distal superficial femoral artery and superior mesenteric artery (SMA), 3 cm from its ostium. Recombinant tissue plasminogen activitor (rtPA) 40 mg was selectively in stilled in the SMA in two boluses. Abdominal symptoms resolved within 48 h, and complete recanalization of the SMA was shown on angiography. Exploratory laparotomy after 72 h showed a normal small bowel and right colon, and was completed by femoropopliteal embolectomy. Six months later, the patient remained asymptomatic.  相似文献   
57.
58.
59.
Summary It has been suggested that age changes in the morphology of the neuromuscular junction (NMJ) may reflect altered physical activity levels rather than the unique effects of ageing. Additionally, previous studies have indicated that the structure of the NMJ may be modulated with exercise. To investigate these questions, quantitative morphometry was determined on soleus and extensor digitorum longus (EDL) nerve terminals stained with zinc iodide-osmium from C57BL/6NNia mice under control and endurance exercised conditions at 12, 18 and 24 months of age.As previously observed, the area, perimeter, extent length and branch number of nerve terminals increased with age in both soleus and EDL. The changes were similar between the muscle types, although the changes were more pronounced in the phasic EDL. In 12-month-old animals, 2 months of endurance exercise resulted in significantly larger nerve terminals in both soleus and EDL, suggesting a functional adaptation. Exercised 18- and 24-month-old nerve terminals were smaller than corresponding controls, which indicated that exercise minimized or prevented further age-related nerve terminal elaboration. At all ages the exercised nerve terminals comprised a more homogeneous population than corresponding controls, which indicates that uniform physical activity can modulate NMJ morphometry. The magnitude of the changes suggests that subtle alterations in normal cage activity with advancing age do not have a significant effect on the morphology of nerve terminals. However, the morphology of the NMJ does change significantly in response to physical exercise training.  相似文献   
60.
Reactions to Alcohol in Sons of Alcoholics and Controls   总被引:3,自引:0,他引:3  
This paper synthesizes some major findings coming from our laboratory over the last decade. The data focuses on our search for mechanisms that might contribute to the elevated risk for alcoholism in sons of alcoholic fathers. Consistent results corroborated by several additional groups indicate that the higher risk sons of alcoholics demonstrate less intense reactions to ethanol as measured by their subjective self-reports, measures of body sway, changes in several hormones after drinking, and the intensity or persistence of ethanol-related changes on two electrophysiological measures. The potential implications of these results as they might relate to an enhanced vulnerability to alcoholism, and some possible future research directions, are discussed.  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