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   1987487篇
  免费   153119篇
  国内免费   4369篇
耳鼻咽喉   26260篇
儿科学   65365篇
妇产科学   54930篇
基础医学   291812篇
口腔科学   54749篇
临床医学   179271篇
内科学   391433篇
皮肤病学   46267篇
神经病学   156200篇
特种医学   74537篇
外国民族医学   531篇
外科学   296640篇
综合类   44826篇
现状与发展   5篇
一般理论   623篇
预防医学   153098篇
眼科学   45493篇
药学   143763篇
  3篇
中国医学   5307篇
肿瘤学   113862篇
  2021年   15664篇
  2019年   16259篇
  2018年   23045篇
  2017年   17451篇
  2016年   19750篇
  2015年   22027篇
  2014年   30871篇
  2013年   45857篇
  2012年   62066篇
  2011年   65753篇
  2010年   38730篇
  2009年   36871篇
  2008年   60712篇
  2007年   64450篇
  2006年   65396篇
  2005年   62672篇
  2004年   60299篇
  2003年   57241篇
  2002年   55383篇
  2001年   99969篇
  2000年   102057篇
  1999年   84518篇
  1998年   23305篇
  1997年   20694篇
  1996年   20914篇
  1995年   19866篇
  1994年   18087篇
  1993年   16905篇
  1992年   64030篇
  1991年   61835篇
  1990年   59689篇
  1989年   57525篇
  1988年   52550篇
  1987年   51269篇
  1986年   48206篇
  1985年   45712篇
  1984年   34389篇
  1983年   28975篇
  1982年   17162篇
  1979年   30522篇
  1978年   21478篇
  1977年   17974篇
  1976年   17105篇
  1975年   18077篇
  1974年   21473篇
  1973年   20679篇
  1972年   19389篇
  1971年   17752篇
  1970年   16953篇
  1969年   15606篇
排序方式: 共有10000条查询结果,搜索用时 781 毫秒
81.
Nevo  N.  Goldstein  A. L.  Staierman  M.  Eran  N.  Carmeli  I.  Rayman  S.  mnouskin  Y. 《Hernia》2022,26(6):1491-1499
Hernia - The minimally invasive surgical repair of combined inguinal and ventral hernias often requires shifting from one approach or plane to another. The traditional enhanced-view totally...  相似文献   
82.
目的探讨维生素D(VitD)联合鱼油对糖尿病前期(PDM)患者糖脂代谢、胰岛β细胞功能的影响。 方法选取PDM患者132例,随机均分为联合组(VitD+鱼油)、VitD组(VitD)和对照组(不干预)。比较各组糖脂代谢、胰岛β细胞功能、炎症反应、血管内皮功能等指标。 结果与干预前比较,干预后联合组甘油三酯降低,白细胞介素-10增高(P<0.05),联合组和VitD组低密度脂蛋白胆固醇、肿瘤坏死因子-α、胰岛素抵抗指数、前列腺素E2、瘦素、抵抗素降低(P<0.05),空腹胰岛素、胰岛β细胞功能指数、脂联素增高(P<0.05),且联合组改善更为明显(P<0.05)。 结论维生素D联合鱼油治疗PDM患者可改善其脂代谢和胰岛功能相关指标,具有一定临床应用价值。  相似文献   
83.

Researchers have highlighted numerous sociocultural factors that have been shown to underpin human appearance enhancement practices, including the influence of peers, family, the media, and sexual objectification. Fewer scholars have approached appearance enhancement from an evolutionary perspective or considered how sociocultural factors interact with evolved psychology to produce appearance enhancement behavior. Following others, we argue that evidence from the field of evolutionary psychology can complement existing sociocultural models by yielding unique insight into the historical and cross-cultural ubiquity of competition over aspects of physical appearance to embody what is desired by potential mates. An evolutionary lens can help to make sense of reliable sex and individual differences that impact appearance enhancement, as well as the context-dependent nature of putative adaptations that function to increase physical attractiveness. In the current review, appearance enhancement is described as a self-promotion strategy used to enhance reproductive success by rendering oneself more attractive than rivals to mates, thereby increasing one’s mate value. The varied ways in which humans enhance their appearance are described, as well as the divergent tactics used by women and men to augment their appearance, which correspond to the preferences of opposite-sex mates in a heterosexual context. Evolutionarily relevant individual differences and contextual factors that vary predictably with appearance enhancement behavior are also discussed. The complementarity of sociocultural and evolutionary perspectives is emphasized and recommended avenues for future interdisciplinary research are provided for scholars interested in studying appearance enhancement behavior.

  相似文献   
84.
Haemophilia is a common cause of genetically inherited bleeding disorders. Pseudotumours occur in 1–2 % of persons with severe forms of haemophilia. These are a result of repeated haemorrhage into soft tissues, subperiosteum or a site of bone fracture with inadequate resorption of the extravasated blood. There are a number of therapeutic alternatives for this dangerous condition: surgical removal, percutaneous management, irradiation, embolization etc. In this case report, we describe the natural history, clinical course and successful surgical management of a patient with haemophilia who presented with a massive pseudotumour. We also briefly review the relevant literature on the various therapeutic modalities that have been implemented in the management of this rare complication. Though surgeons may be averse to operate on haemophiliacs, primary surgical management as done in our case may prove to be the definitive treatment option for such patients.  相似文献   
85.
86.
87.
88.
89.
90.
Thermal ablation of liver tumors near large blood vessels is affected by the cooling effect of blood flow, leading to incomplete ablation. Hence, we conducted a comparative investigation of heat sink effect in monopolar (MP) and bipolar (BP) radiofrequency ablation (RFA), and microwave (MW) ablation devices.With a perfused calf liver, the ablative performances (volume, mass, density, dimensions), with and without heat sink, were measured. Heat sink was present when the ablative tip of the probes were 8.0 mm close to a major hepatic vein and absent when >30 mm away. Temperatures (T1 and T2) on either side of the hepatic vein near the tip of the probes, heating probe temperature (T3), outlet perfusate temperature (T4), and ablation time were monitored.With or without heat sink, BP radiofrequency ablated a larger volume and mass, compared with MP RFA or MW ablation, with latter device producing the highest density of tissue ablated. MW ablation produced an ellipsoidal shape while radiofrequency devices produced spheres.Percentage heat sink effect in Bipolar radiofrequency : Mono-polar radiofrequency : Microwave was (Volume) 33:41:22; (mass) 23:56:34; (density) 9.0:26:18; and (relative elipscity) 5.8:12.9:1.3, indicating that BP and MW devices were less affected.Percentage heat sink effect on time (minutes) to reach maximum temperature (W) = 13.28:9.2:29.8; time at maximum temperature (X) is 87:66:16.66; temperature difference (Y) between the thermal probes (T3) and the temperature (T1 + T2)/2 on either side of the hepatic vessel was 100:87:20; and temperature difference between the (T1 + T2)/2 and temperature of outlet circulating solution (T4), Z was 20.33:30.23:37.5.MW and BP radiofrequencies were less affected by heat sink while MP RFA was the most affected. With a single ablation, BP radiofrequency ablated a larger volume and mass regardless of heat sink.  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