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   17923篇
  免费   1112篇
  国内免费   141篇
耳鼻咽喉   111篇
儿科学   493篇
妇产科学   380篇
基础医学   2872篇
口腔科学   342篇
临床医学   1466篇
内科学   4501篇
皮肤病学   301篇
神经病学   1803篇
特种医学   447篇
外科学   1462篇
综合类   48篇
一般理论   5篇
预防医学   1393篇
眼科学   205篇
药学   1331篇
中国医学   61篇
肿瘤学   1955篇
  2024年   24篇
  2023年   193篇
  2022年   389篇
  2021年   661篇
  2020年   396篇
  2019年   545篇
  2018年   589篇
  2017年   490篇
  2016年   548篇
  2015年   602篇
  2014年   764篇
  2013年   1015篇
  2012年   1641篇
  2011年   1634篇
  2010年   899篇
  2009年   829篇
  2008年   1336篇
  2007年   1216篇
  2006年   1160篇
  2005年   1003篇
  2004年   912篇
  2003年   758篇
  2002年   652篇
  2001年   84篇
  2000年   47篇
  1999年   94篇
  1998年   122篇
  1997年   99篇
  1996年   92篇
  1995年   50篇
  1994年   44篇
  1993年   49篇
  1992年   28篇
  1991年   25篇
  1990年   23篇
  1989年   9篇
  1988年   12篇
  1987年   17篇
  1986年   10篇
  1985年   7篇
  1984年   17篇
  1983年   11篇
  1982年   12篇
  1981年   10篇
  1980年   9篇
  1979年   6篇
  1978年   5篇
  1975年   6篇
  1973年   10篇
  1971年   4篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
Neurological Sciences - Patients with mild cognitive impairment (MCI) might experience difficulties in numerical and financial abilities of daily living that compromise their autonomy. The aim of...  相似文献   
82.
83.
Background: Nutritional quality during pregnancy is crucial for mother and child health and their short/long-term outcomes. The aim of this study is to evaluate the adherence to nutritional recommendations in Italy during the three pregnancy trimesters in Normal Weight (NW) and Over Weight (OW) women. Methods: Data from a multicenter randomized controlled trial included 176 women (NW = 133; OW = 43) with healthy singleton pregnancies enrolled within 13 + 6 weeks of gestation. Dietary intake was assessed every trimester by a Food Frequency Questionnaire. Results: OW and NW had similar gestational weight gain. However, as Institute of Medicine (IOM) recommend lower gestational weight gain (GWG) for OW, they exceeded the suggested range. In both groups, caloric intake during the three trimesters never met recommendations. Protein intake in first and second trimester was higher than recommendations, as was sugars percentage. Dietary fiber intake was lower in OW. Polyunsaturated fatty acids, calcium, iron and folic acid requirements were never satisfied, while sodium intake exceeded recommendations. Conclusions: NW and OW women in Italy do not adhere to nutritional recommendations during pregnancy, with lower caloric intake, protein and sugars excess and inadequacies in micronutrients intake. Pregnant women in Italy should be provided with an adequate counseling and educational intervention as well as supplementation when indicated.  相似文献   
84.
Tin-bronze alloys with a tin content of at least 10 wt% have excellent mechanical properties, wear resistance, and corrosion resistance. Among these alloys, Cu-10Sn was investigated in this study for production with the laser powder bed fusion process with a 500W Yb:YAG laser. In particular, a design of experiment (DoE) was developed in order to identify the optimal process parameters to obtain full density, low surface roughness, and high dimensional accuracy. Samples were characterized with Archimedes’ method and optical microscopy to determine their final density. It was shown that the first method is fast but not as reliable as the second one. A first mechanical characterization was performed through microhardness tests. Finally, a set of process parameters was identified to produce fully dense samples with low surface roughness and high accuracy. The results showed that the volumetric energy density could represent an approach that is too simplified, therefore limiting the direct correlation with the physical aspects of the process.  相似文献   
85.
86.
Necrotizing fasciitis is defined as a rapidly progressive infection of the skin and soft tissue that usually involves severe systemic toxicity. The incidence of this infection has increased in the last few decades and is estimated to affect one out of every 100,000 inhabitants in western European countries. This disease is the most serious form of skin and soft tissue infection, due to rapid destruction and necrosis of the fascia and subcutaneous fat, and the development of shock and multiorgan failure in about one third of patients.Although there are several predisposing factors for the development of the disease, especially for type I, or polymicrobial, necrotizing fasciitis, many patients are young and have no underlying chronic diseases, as is the case for type II, or streptococcal, necrotizing fasciitis. The diagnosis is mainly clinical, and urgent surgical consultation is required as soon as possible once suspicion is high, as the main determinant of mortality is the delay in surgical treatment. Overall mortality remains high, affecting more than 25% of patients. Surgical debridement is the mainstay of treatment, along with hemodynamic support and broad-spectrum antibiotics.  相似文献   
87.
88.
89.
90.
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