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   4690686篇
  免费   368608篇
  国内免费   14918篇
耳鼻咽喉   66392篇
儿科学   150796篇
妇产科学   124658篇
基础医学   710987篇
口腔科学   128950篇
临床医学   425067篇
内科学   853801篇
皮肤病学   114923篇
神经病学   389187篇
特种医学   182862篇
外国民族医学   815篇
外科学   718855篇
综合类   130787篇
现状与发展   23篇
一般理论   2726篇
预防医学   389341篇
眼科学   110804篇
药学   330165篇
  26篇
中国医学   12415篇
肿瘤学   230632篇
  2021年   56712篇
  2019年   59379篇
  2018年   76215篇
  2017年   58472篇
  2016年   64980篇
  2015年   77055篇
  2014年   111636篇
  2013年   178084篇
  2012年   136453篇
  2011年   144872篇
  2010年   130733篇
  2009年   130296篇
  2008年   131052篇
  2007年   140342篇
  2006年   147986篇
  2005年   143302篇
  2004年   142897篇
  2003年   133428篇
  2002年   122681篇
  2001年   172174篇
  2000年   168544篇
  1999年   153136篇
  1998年   72757篇
  1997年   68106篇
  1996年   66295篇
  1995年   61517篇
  1994年   55543篇
  1993年   51622篇
  1992年   110559篇
  1991年   106558篇
  1990年   102985篇
  1989年   100277篇
  1988年   92654篇
  1987年   91064篇
  1986年   86155篇
  1985年   84429篇
  1984年   69926篇
  1983年   62315篇
  1982年   49001篇
  1981年   45567篇
  1980年   42905篇
  1979年   61472篇
  1978年   49400篇
  1977年   43287篇
  1976年   40526篇
  1975年   41223篇
  1974年   45952篇
  1973年   44034篇
  1972年   41308篇
  1971年   38417篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
993.
994.
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   
995.
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   
996.
997.
998.
999.
1000.
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   
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