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   24819篇
  免费   2048篇
  国内免费   57篇
耳鼻咽喉   402篇
儿科学   742篇
妇产科学   729篇
基础医学   3216篇
口腔科学   628篇
临床医学   3020篇
内科学   4216篇
皮肤病学   199篇
神经病学   1821篇
特种医学   867篇
外科学   3725篇
综合类   569篇
一般理论   13篇
预防医学   2916篇
眼科学   438篇
药学   1741篇
中国医学   45篇
肿瘤学   1637篇
  2021年   346篇
  2020年   220篇
  2019年   360篇
  2018年   410篇
  2017年   304篇
  2016年   296篇
  2015年   361篇
  2014年   494篇
  2013年   753篇
  2012年   1109篇
  2011年   1098篇
  2010年   616篇
  2009年   542篇
  2008年   1018篇
  2007年   1113篇
  2006年   972篇
  2005年   956篇
  2004年   995篇
  2003年   910篇
  2002年   865篇
  2001年   879篇
  2000年   871篇
  1999年   723篇
  1998年   377篇
  1997年   351篇
  1996年   333篇
  1995年   313篇
  1994年   230篇
  1993年   196篇
  1992年   607篇
  1991年   526篇
  1990年   507篇
  1989年   496篇
  1988年   490篇
  1987年   432篇
  1986年   470篇
  1985年   457篇
  1984年   365篇
  1983年   301篇
  1982年   210篇
  1981年   196篇
  1980年   215篇
  1979年   346篇
  1978年   237篇
  1977年   224篇
  1975年   187篇
  1974年   227篇
  1973年   204篇
  1972年   199篇
  1969年   198篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
101.
102.
Surgical complications of continuous ambulatory peritoneal dialysis   总被引:4,自引:0,他引:4  
Surgical experience with 260 consecutive patients with chronic renal failure receiving continuous ambulatory peritoneal dialysis (CAPD) at one medical center from 1980 to 1989 is reviewed. Patients received CAPD for a mean of 24.2 months (range: 3 days to 91 months). Catheter longevity consistently improved in all but 1 year from 1984 to 1989, as did exit-site and tunnel infections. Of 311 catheters inserted, 151 (49%) required removal, of which 111 (74%) were attributed to peritonitis. Cumulative patient survival was 80%, 60%, and 53% at 1, 2, and 3 years, respectively. Diabetic patients had statistically significant lower survival rates. Additional complications including catheter leakage, catheter malposition, catheter obstruction, and abdominal wall hernias were negligible. Although CAPD is not free from serious complications, our data show remarkable improvement since 1980 in catheter longevity, hospital stay, and infection rates.  相似文献   
103.
104.
I present a review of the pattern of rare craniofacial clefting in patients presenting to a tertiary referral craniofacial unit. Patients with an isolated rare cleft were uncommon; most had multiple axes of disruption. Midline and paramedian facial clefts, although occasionally occurring alone, often overlap with adjacent facial clefts and extend along an upward cranial axis. The corresponding midline and paramedian facial clefts were never seen in isolation but were almost always seen with their axial downward cleft. Lateral nasal, oro-ocular, and lateral forehead clefts showed diffuse and often poorly defined regions of disruption, resulting in a multiplicity in clefts. The small subgroup of patients with features of the amniotic band sequence had more and differently distributed clefts compared with the larger nonamniotic band group.  相似文献   
105.
Homologous pairing and strand exchange of DNA are catalyzed by the human homologous pairing protein HPP-1 in a magnesium-dependent, ATP-independent reaction that requires homologous DNA substrates and stoichiometric quantities of HPP-1. Here we show that the addition of the purified human single-strand binding (SSB) protein hRP-A to the reaction mixture stimulates the rate of homologous pairing 70-fold and reduces the amount of HPP-1 required for the reaction at least 10-fold. The identification of hRP-A as a stimulatory factor of HPP-1-catalyzed reaction was facilitated by its recognition as a member of a high molecular weight complex of recombination components. Neither the Escherichia coli SSB protein, bacteriophage T4 gene 32 protein, nor the highly conserved Saccharomyces cerevisiae yRP-A SSB protein could substitute for hRP-A in this stimulation. Because only the cognate SSB was capable of stimulating HPP-1, these results suggest that eukaryotes depend on unique and specific interactions between DNA recombination components.  相似文献   
106.
107.
Schools of public health have been cautioned about producing graduates and research that were disconnected from public interest. Although institutions may implement a variety of strategies to rectify the situation, institutional structural and cultural barriers impede progress. Public health practice coordinators in accredited schools of public health were surveyed to describe the presence of structural and cultural barriers to academic public health practice using the Stevens model. Administrative leadership and faculty reward systems are described as critical to advance academic public health practice.  相似文献   
108.
Extracranial approaches to the repair of cerebrospinal fluid rhinorrhea.   总被引:4,自引:0,他引:4  
This paper presents a review of the extracranial evaluation and treatment of cerebrospinal fluid (CSF) rhinorrhea. Diagnosis with attention to a careful history and physical with maneuvers which exacerbate drainage and thorough physical exam along with imaging techniques are discussed. The common etiologies of CSF rhinorrhea including trauma, spontaneous leakage, tumor, and iatrogenic injury are included. Management consists of conservative measures including the avoidance of straining maneuvers which increases intracranial pressure. Periodic drainage of CSF via lumbar puncture or continuous drainage via flow-regulated systems may also be of benefit in attempts of conservative management. Failure of conservative management, constant leakage, pneumocephalus, and recurrent meningitis are indicators for surgical repairs. Ethmoid-cribiform plate region repairs are generally approached by external ethmoidectomy and the development of mucoperiosteal flaps from various donor sites which are then rotated to the leak area to seal the defect. Frontal sinus leaks are usually repaired via an osteoplastic flap technique with direct repair of the dural defect or the use of fascial graft tucked under the bony defect, then obliterated with abdominal fat. CSF rhinorrhea presents a diagnostic and surgical challenge to the otolaryngologist. After diagnosis and localization, operative repair using extracranial approaches is accepted as the initial method of intervention in these cases.  相似文献   
109.
Abstract: We describe a new case of a rare syndrome characterized by ocular abnormalities and pathognomonic linear skin defects. This syndrome is the result of an unbalanced translocation resulting in a deletion of the distal end of the short arm of the X chromosome. We report the thirteenth case and review the clinical and cytogenetic aspects of this disorder. In addition we discuss new findings pertaining to the histopathology of the skin lesions.  相似文献   
110.
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