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   244626篇
  免费   20603篇
  国内免费   14524篇
耳鼻咽喉   2208篇
儿科学   3088篇
妇产科学   4898篇
基础医学   28441篇
口腔科学   4243篇
临床医学   31212篇
内科学   40040篇
皮肤病学   2823篇
神经病学   13620篇
特种医学   8659篇
外国民族医学   96篇
外科学   27082篇
综合类   34707篇
现状与发展   48篇
一般理论   45篇
预防医学   15392篇
眼科学   6682篇
药学   24389篇
  164篇
中国医学   11080篇
肿瘤学   20836篇
  2024年   710篇
  2023年   3495篇
  2022年   8688篇
  2021年   11443篇
  2020年   8406篇
  2019年   7607篇
  2018年   8004篇
  2017年   7001篇
  2016年   6690篇
  2015年   10156篇
  2014年   12785篇
  2013年   12033篇
  2012年   17772篇
  2011年   19518篇
  2010年   12047篇
  2009年   9655篇
  2008年   12994篇
  2007年   13053篇
  2006年   12588篇
  2005年   12655篇
  2004年   8744篇
  2003年   7724篇
  2002年   6648篇
  2001年   6025篇
  2000年   6142篇
  1999年   6409篇
  1998年   3649篇
  1997年   3670篇
  1996年   2789篇
  1995年   2583篇
  1994年   2233篇
  1993年   1499篇
  1992年   2289篇
  1991年   1996篇
  1990年   1664篇
  1989年   1458篇
  1988年   1264篇
  1987年   1176篇
  1986年   941篇
  1985年   749篇
  1984年   491篇
  1983年   381篇
  1982年   225篇
  1981年   201篇
  1980年   191篇
  1979年   243篇
  1978年   141篇
  1977年   112篇
  1976年   97篇
  1974年   116篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
31.
32.
33.
34.
The use of low levels of visible or near infrared light for reducing pain, inflammation and edema, promoting healing of wounds, deeper tissues and nerves, and preventing cell death and tissue damage has been known for over forty years since the invention of lasers. Despite many reports of positive findings from experiments conducted in vitro, in animal models and in randomized controlled clinical trials, LLLT remains controversial in mainstream medicine. The biochemical mechanisms underlying the positive effects are incompletely understood, and the complexity of rationally choosing amongst a large number of illumination parameters such as wavelength, fluence, power density, pulse structure and treatment timing has led to the publication of a number of negative studies as well as many positive ones. A biphasic dose response has been frequently observed where low levels of light have a much better effect on stimulating and repairing tissues than higher levels of light. The so-called Arndt-Schulz curve is frequently used to describe this biphasic dose response. This review will cover the molecular and cellular mechanisms in LLLT, and describe some of our recent results in vitro and in vivo that provide scientific explanations for this biphasic dose response.  相似文献   
35.
Purpose Post operative monitoring is crucial for the success of microsurgical free tissue transfer. Sophisticated and expensive methods are available for monitoring. We propose a novel technique using digital photography and the internet as a reliable and cost effective method to monitor free tissue transfers. Methods 163 micro‐vascular procedures were monitored using this technique over 8 months. Serial photographs taken to show flap color. Capillary refill time, pin prick‐ bleed time and color and hand held Doppler signal was recorded in the movie mode of a standard 5 mega pixel camera with duration of 15 seconds. Data was sent to the surgeon at regular intervals and or as deemed necessary. Results Analysis of the 67 cases is presented. 5 re‐explorations were done. The early diagnosis of venous congestion was possible using this technique. Timely intervention contributed to the success of the re‐explorations and these flaps could be salvaged. The file size of images was in the range of 1 MB–6 MB. The file size of an entire set of images ranged about 7 MB–9 MB. These were sent across the ADSL internet lines. Conclusion The use of the digital images and the internet allow reconstructive surgeons to have a reliable picture of the state of their free tissue transfers. This permits decrease in observer error and saves valuable time which otherwise needs to be spent to verify situations of doubt and offers an ideal solution to the logistic problem of having to visit the patient in case of doubt.  相似文献   
36.
37.
腹主动脉瘤的治疗方法和中远期效果评价   总被引:1,自引:0,他引:1  
随着人口老龄化,以及高血压、动脉硬化等高危因素的增加,腹主动脉瘤(abdominal aortic aneurysm,AAA)的发病率也随之增高。最新数据表明美国每年约有30,000人死于AAA破裂,一旦破裂死亡率高达90%[1],因此早期诊断,积极治疗,防止破裂意义重大。AAA治疗方法主要包括开放手术和腔内  相似文献   
38.
The adequate treatment of methicillin-resistant Staphylococcus aureus (MRSA) osteomyelitis has intrigued clinicians for some time. As the resistance of these pathogens, coupled with the increase in community-acquired cases, continues steadily to rise, clinicians are finding it useful to employ multi-modal approaches for efficacious treatment. The authors present a single case report of a patient with recurrent MRSA osteomyelitis, lumbar paraspinal and epidural abscess. He was found to have decreased muscle strength and was hyporeflexic in the involved extremity. Serum testing demonstrated MRSA bacteremia. Neuroimaging studies revealed evidence of paraspinal abscess and a presumed herniated nucleus pulposus at the L5/S1 interspace with significant nerve root compromise. Despite antimicrobials, his symptoms persisted, necessitating surgical exploration. At surgery, paraspinal and epidural abscesses were encountered and debrided; however, no herniated disc was visualized. This case demonstrates the diagnostic and therapeutic dilemmas with which these lesions present. We postulate that the MRSA osteomyelitis/discitis pathogens were walled off in the disc space and subsequently inoculated the soft tissues with ensuing bacteremia. We concur that antimicrobial treatment should be the first line of therapy for these patients; however, surgical debridements and cautious spinal instrumentation should be employed where appropriate.  相似文献   
39.
Functional separation of the lungs may be accomplished by several methods. Patient with restricted mouth opening has limited options for one-lung ventilation. We report the use of wire-guided endobronchial blockade, a new tool for achieving one-lung ventilation in a patient with restricted mouth opening requiring nasotracheal, fiberoptic intubation for esophagectomy and reconstruction with gastric tube substitution.  相似文献   
40.
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