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   242214篇
  免费   20455篇
  国内免费   14386篇
耳鼻咽喉   2178篇
儿科学   3050篇
妇产科学   4882篇
基础医学   28325篇
口腔科学   4216篇
临床医学   30866篇
内科学   39870篇
皮肤病学   2830篇
神经病学   13544篇
特种医学   8591篇
外国民族医学   96篇
外科学   26663篇
综合类   34087篇
现状与发展   48篇
一般理论   45篇
预防医学   15094篇
眼科学   6675篇
药学   24195篇
  164篇
中国医学   10913篇
肿瘤学   20723篇
  2024年   709篇
  2023年   3490篇
  2022年   8680篇
  2021年   11420篇
  2020年   8381篇
  2019年   7593篇
  2018年   7993篇
  2017年   6969篇
  2016年   6666篇
  2015年   10086篇
  2014年   12693篇
  2013年   11886篇
  2012年   17532篇
  2011年   19216篇
  2010年   11721篇
  2009年   9382篇
  2008年   12764篇
  2007年   12806篇
  2006年   12364篇
  2005年   12443篇
  2004年   8601篇
  2003年   7638篇
  2002年   6610篇
  2001年   5989篇
  2000年   6105篇
  1999年   6410篇
  1998年   3666篇
  1997年   3691篇
  1996年   2802篇
  1995年   2592篇
  1994年   2235篇
  1993年   1504篇
  1992年   2291篇
  1991年   1995篇
  1990年   1666篇
  1989年   1460篇
  1988年   1270篇
  1987年   1182篇
  1986年   947篇
  1985年   766篇
  1984年   499篇
  1983年   384篇
  1982年   231篇
  1981年   208篇
  1980年   196篇
  1979年   244篇
  1978年   144篇
  1977年   114篇
  1976年   99篇
  1974年   116篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
41.
Twenty-two infants of isolated ventricular septal defect with congestive heart failure were fed with lower-sodium content formula-Lonalac (Mead-Johnson) to study the clinical response of treatment for congestive heart failure. There were no significant changes of intake, urinary output, serum sodium, potassium and osmolality before, 2 days and 6 days after Lonalac feeding. The low sodium content formula may feed the infants with congestive heart failure in addition to the traditional anticongestive therapy.  相似文献   
42.
Ductal adenoma of the breast   总被引:1,自引:0,他引:1  
Ductal adenoma is a recently described benign tumour of the breast that can be mistaken for carcinoma in both frozen and paraffin sections. Such a case is presented. Fortunately a mastectomy was not performed, but the patient did undergo axillary node dissection. Surgeons and pathologists should familiarize themselves with this lesion so that patients do not have to undergo unnecessary mastectomies and axillary node dissections.  相似文献   
43.
The hereditary characteristics of enzyme deficiency and dermatoglyphics in congenital color blindness (CCB) were studied. We propose that there is a linkage between the two loci on the X-chromosome determining CCB and glucose-6-phosphate dehydrogenase (G6PD), based on our study of a high incidence of G6PD deficiency in 156 male cases with CCB. The CCB gene is closely linked with that of G6PD deficiency from our pedigree investigations. The rise in the frequency of eight or more whorls, the low value of atd angle and the presenting rate of real palmar patterns of the thenar, hypothenar and I, areas presented the hereditary traits of congenital color blindness.  相似文献   
44.
45.
46.
Endothelial cell antigens recognized by xenoreactive human natural antibodies.   总被引:10,自引:0,他引:10  
Hyperacute rejection of vascularized, discordant xenografts is generally though to be initiated when natural antibodies of the recipient bind to endothelial cells of the donor organ. While rejection of such xenografts always occurs, the molecular targets of natural antibodies have not been elucidated. The aim of the experiments reported herein was to identify the molecules on porcine endothelial cells that would be recognized by human natural antibodies if a porcine organ were to be transplanted into a human (or rhesus). Toward the end, it was shown that the major components recognized by human serum on porcine endothelial cells are glycoproteins of 115kDa, 125kDa, and 135kDa (gp115/135). Reactivity with these glycoproteins was abrogated by enzymatic cleavage of N-linked oligosaccharides or of subterminal beta-D-gal residues suggesting that the determinants are located on oligosaccharides rather than on the polypeptide cores. The biological relevance of gp115/135 was suggested by experiments in which a similar series of components was shown to be recognized by rhesus natural antibodies and by the absorption of such antibodies by perfusion of porcine kidneys. The gp115/135 antigens were present on porcine platelets but not porcine RBC or lymphocytes. Nevertheless, purified RBC and lymphocytes absorbed human anti-gp115/135, suggesting that human natural antibodies recognize the same or crossreactive carbohydrate determinants expressed on the surface of a variety of cells.  相似文献   
47.
不同术后镇痛模式对红细胞免疫功能的影响   总被引:4,自引:1,他引:3  
目的探讨不同术后镇痛模式对红细胞免疫功能的影响。方法50例妇科手术患者,按术后不同镇痛模式分为硬膜外自控镇痛(PCEA)组和静脉自控镇痛(PCIA)组。并分别于术前、术后1、3、7 d采静脉血样检测红细胞C3b受体花环率(RCR)、红细胞免疫复合物花环率(RICR)、红细胞免疫粘附促进因子(RFER)和红细胞免疫粘附抑制因子(RFIR)。结果与术前比,PCEA组术后1 d RCR、RFER显著上升(P<0.05),RFIR显著下降(P<0.05),术后3 d RCR、RFER仍显著上升(P<0.05),而RICR显著下降(P<0.05);PCIA组术后1 d RCR、RFER显著下降(P<0.05),RFIR、RICR显著上升(P<0.05);PCIA组术后1、3 d RCR、RFER比PCEA组显著降低(P<0.05),而RICR显著上升(P<0.05);两组各参数在术后7 d基本恢复至术前水平。结论PCEA对红细胞免疫功能的稳定和恢复作用明显强于PCIA。  相似文献   
48.
49.
合同制护士存在的问题分析与对策   总被引:1,自引:1,他引:0  
陈维荣 《护理研究》2007,21(33):3079-3080
科学技术飞速发展的今天,在知识经济市场与服务竞争的大潮中,每个行业都在寻求新的机遇,面对新的挑战,存在新的危机,合同制护士表现尤为突出,存在着工资收入低、工作压力大、工作稳定性差等问题。现就其现状作一分析,提出相应对策。1合同制护士的现状分析近年来,合同制一词在人们生活中已不再陌生,并逐渐被人们接受。合同制护士在医院的护理队伍中工资收入、职称晋升、医疗保险、福利待遇等方面均与正式在编护士有着很大的差异。由于近年来护理专业毕业生急剧增长,面对当前就业难的压力和激烈的竞争环境,她们相继到各大医院竞聘,而医院招工…  相似文献   
50.
We report a case of calcified chronic encapsulated intracerebral haematoma (ICH) in a 29-year-old female who presented with progressive left sided weakness and intermittent seizures since childhood. The preoperative magnetic resonance (MR) imaging of the head initially suggested that a partially thrombosed aneurysm or vascular malformation was present. However, no vascular stain was found on the digital subtraction angiography (DSA) of both the carotid and vertebral arteries. The excised mass was histologically diagnosed as a chronic ICH. We traced the patient's medical history and found that at the age of one she sustained a head injury after a fall. So far, to our knowledge, no case of epilepsy secondary to a calcified chronic encapsulated ICH occurring 28 years after head injury has been reported. Calcified chronic encapsulated ICH concomitant with new bone formation within is even rarer. The possible pathogenesis of this case is discussed.  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