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   3131363篇
  免费   268761篇
  国内免费   13656篇
耳鼻咽喉   42594篇
儿科学   98073篇
妇产科学   77894篇
基础医学   509465篇
口腔科学   83574篇
临床医学   283464篇
内科学   544715篇
皮肤病学   87172篇
神经病学   267914篇
特种医学   122707篇
外国民族医学   114篇
外科学   489867篇
综合类   95628篇
现状与发展   23篇
一般理论   2186篇
预防医学   264290篇
眼科学   71863篇
药学   212943篇
  23篇
中国医学   9928篇
肿瘤学   149343篇
  2022年   23601篇
  2021年   55945篇
  2020年   35727篇
  2019年   58947篇
  2018年   71773篇
  2017年   54689篇
  2016年   60291篇
  2015年   74666篇
  2014年   109090篇
  2013年   174476篇
  2012年   88707篇
  2011年   88204篇
  2010年   116784篇
  2009年   121260篇
  2008年   74465篇
  2007年   76811篇
  2006年   87779篇
  2005年   82997篇
  2004年   84574篇
  2003年   75282篇
  2002年   65085篇
  2001年   86495篇
  2000年   78404篇
  1999年   81762篇
  1998年   63654篇
  1997年   61746篇
  1996年   59372篇
  1995年   54877篇
  1994年   49045篇
  1993年   45777篇
  1992年   55171篇
  1991年   52926篇
  1990年   49970篇
  1989年   50077篇
  1988年   46357篇
  1987年   45066篇
  1986年   42852篇
  1985年   43329篇
  1984年   41507篇
  1983年   38523篇
  1982年   39141篇
  1981年   37173篇
  1980年   35140篇
  1979年   33264篇
  1978年   31075篇
  1977年   28830篇
  1976年   26522篇
  1975年   25106篇
  1974年   24921篇
  1973年   23799篇
排序方式: 共有10000条查询结果,搜索用时 35 毫秒
991.
992.
Nickel is the leading cause of allergic contact dermatitis (ACD) from early childhood through adolescence. Studies have shown that skin piercings and other nickel‐laden exposures can trigger the onset of nickel ACD in those who are susceptible. Nickel ACD causes a vast amount of cutaneous disease in children. Cases of nickel ACD in children have been reported in peer‐reviewed literature from 28 states. Common items that contain inciting nickel include jewelry, coins, zippers, belts, tools, toys, chair studs, cases for cell phones and tablets, and dental appliances. The diagnosis of nickel ACD has been routinely confirmed by patch testing in children older than 6 months suspected of ACD from nickel. Unlike in Europe, there are no mandatory restrictions legislated for nickel exposure in the United States. Denmark has demonstrated that regulation of the nickel content in metals can lower the risk of ACD and the associated health care–related costs that arise from excess nickel exposure. To further awareness, this article reviews the prominent role of nickel in pediatric skin disease in the United States. It discusses the need for a campaign by caretakers to reduce nickel‐related morbidity. Lastly, it promotes the model of European legislation as a successful intervention in the prevention of nickel ACD.  相似文献   
993.
A 3‐year‐old Arab boy with a history of hypoplastic left heart syndrome was referred to the pediatric dermatology clinic at Sheba Medical Center for evaluation of hypomelanosis, manifested by fair skin pigmentation and silvery‐grey hair, eyebrows, and eyelashes. The child had one older brother with similar hypopigmentation and another older brother who had died of congenital heart disease. The child had no history of neurologic deficits or immunodeficiency and no additional findings on clinical evaluation.  相似文献   
994.
995.
996.
997.
998.
Fluid is usually restricted during thoracic surgery, and vasoactive agents are often administered to maintain blood pressure. One-lung ventilation (OLV) decreases arterial oxygenation; thus oxygen delivery to the brain can be decreased. In this study, we compared phenylephrine and dopamine with respect to maintaining cerebral oxygenation during OLV in major thoracic surgery.Sixty-three patients undergoing lobectomies were randomly assigned to the dopamine (D) or phenylephrine (P) group. The patients’ mean arterial pressure was maintained within 20% of baseline by a continuous infusion of dopamine or phenylephrine. Maintenance fluid was kept at 5 mL/kg/h. The depth of anesthesia was maintained with desflurane 1MAC and remifentanil infusion under bispectral index guidance. Regional cerebral oxygen saturation (rScO2) and hemodynamic variables were recorded using near-infrared spectroscopy and esophageal cardiac Doppler.The rScO2 was higher in the D group than the P group during OLV (OLV 60 min: 71 ± 6% vs 63 ± 12%; P = 0.03). The number of patients whose rScO2 dropped more than 20% from baseline was 0 and 6 in the D and P groups, respectively (P = 0.02). The D group showed higher cardiac output, but lower mean arterial pressure than the P group (4.7 ± 1.0 vs 3.9 ± 1.2 L/min; 76.7 ± 8.1 vs 84.5 ± 7.5 mm Hg; P = 0.02, P = 0.02). Among the variables, age, hemoglobin concentration, and cardiac output were associated with rScO2 by correlation analysis.Dopamine was superior to phenylephrine in maintaining cerebral oxygenation during OLV in thoracic surgery.  相似文献   
999.
1000.
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