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   9206篇
  免费   415篇
  国内免费   58篇
耳鼻咽喉   96篇
儿科学   172篇
妇产科学   212篇
基础医学   1289篇
口腔科学   262篇
临床医学   605篇
内科学   2189篇
皮肤病学   290篇
神经病学   748篇
特种医学   467篇
外科学   1143篇
综合类   19篇
一般理论   2篇
预防医学   418篇
眼科学   153篇
药学   651篇
中国医学   21篇
肿瘤学   942篇
  2023年   42篇
  2021年   151篇
  2020年   96篇
  2019年   151篇
  2018年   169篇
  2017年   138篇
  2016年   145篇
  2015年   149篇
  2014年   229篇
  2013年   265篇
  2012年   426篇
  2011年   485篇
  2010年   306篇
  2009年   265篇
  2008年   468篇
  2007年   555篇
  2006年   494篇
  2005年   537篇
  2004年   455篇
  2003年   531篇
  2002年   487篇
  2001年   288篇
  2000年   259篇
  1999年   264篇
  1998年   144篇
  1997年   96篇
  1996年   92篇
  1995年   69篇
  1994年   61篇
  1993年   60篇
  1992年   173篇
  1991年   141篇
  1990年   153篇
  1989年   145篇
  1988年   111篇
  1987年   122篇
  1986年   116篇
  1985年   95篇
  1984年   65篇
  1983年   51篇
  1982年   33篇
  1981年   36篇
  1980年   34篇
  1979年   81篇
  1978年   46篇
  1977年   38篇
  1973年   30篇
  1970年   30篇
  1969年   36篇
  1967年   31篇
排序方式: 共有9679条查询结果,搜索用时 15 毫秒
1.
2.
3.
4.
Platinum (Pt) levels were determined in various tissues and body fluids obtained from a patient who died 181 days after cisplatin overdosing. The symptoms of cisplatin overdose, however, might have almost disappeared by day 40, and the patient’s death was ascribed to the recurrence of malignant lymphoma. Determination of Pt derived from cisplatin was performed by electrospray ionization mass spectrometry (ESI-MS) using silver (Ag) as internal standard. Pt and Ag complexed with diethyldithiocarbamate (DDC) in wetashed blood, and tissue solutions were extracted into isoamyl alcohol, and then acidified with oxalic acid. By injecting an aliquot of the isoamyl alcohol layer into a mass spectrometer in the direct flow injection mode, the quantitation was performed using the signals of Pt(DDC)3 + and Ag(DDC)2 + at m/z 639 and 403, respectively. The Pt levels ranged from 25ng/ml in blood to 2050ng/g wet weight in the liver of the patient, indicating that Pt remained at high levels in tissues, even after a period as long as 181 days after cisplatin overdosing.  相似文献   
5.
近年来,虽然遭遇阻力,但日本国内对于中日战争时期日军在华实施性暴力的调查、研究工作还是取得了重要进展。以石田米子为中心的调查小组经过长期不懈的努力,对当年日军在山西省盂县实施性暴力的事实进行了确证和揭露。本文在介绍石田小组的工作及其意义的同时,还对战时日军的性暴力活动进行了分类,并结合史学理论探讨了利用口述史料研究中国近现代史的意义与可能性。  相似文献   
6.
OBJECTIVES: To reveal the frequency and the clinical characteristics of dystrophic calcification that occurs in children with juvenile dermatomyositis, multi-center analysis was constructed. METHOD: Fifty children with JDM were enrolled, and 14 of them (28.0%) were complicated with calcinosis. Clinical symptoms and laboratory tests at onset, initial therapy and disease course were compared in children with and without calcinosis. RESULTS: The mean age of the onset of calcinosis was 4.78 +/- 3.33 years, and it was younger than those of children without calcinosis (8.66 +/- 3.85 years) (P = 0.0017). No differences of clinical manifestation except Gower's sign were observed. The frequency of positive anti-nuclear antibody was 7.1% in children with calcinosis and 52.9% without calcinosis (P = 0.0112). The initial therapy of methylprednisolon pulses gave no effects on prognosis of calcium deposition. The calcinosis appeared in 1.56 +/- 1.91 year after the onset of the disease. The various types of calcium deposition including large tumorous clumps, subcutaneous plaques or nodules, sheet-type calcification were deserved. They appeared over knee joints (64.3%), elbow joint (64.3%), and hip processes (50.0%). Calcinosis affecting the subcutaneous tissues frequently resulted in painful superficial ulceration of the overlying skin (42.9%), local infection (50.0%), and limitation of joint movement (14.3%). Although aluminum phosphate was effective in 2 children among 7, no other effective treatment was recommended. In 5 cases, surgical removal of tumorous clumps was operated. Thus, juvenile dermatomyositis is frequently complicated with calcinosis. This type of calcinosis was found to be unlikely to resolve completely, and resulted in severe disability in children.  相似文献   
7.
Bronchial venous plexus and its communication with pulmonary circulation   总被引:2,自引:0,他引:2  
This study was undertaken to clarify the microvascular anatomy of the normal human bronchial circulation, focusing on the bronchial venous system and its communication with the pulmonary circulation. Ten normal lungs obtained at autopsy were studied. Bronchial arteriography was performed in six lungs, pulmonary arteriography in two lungs, and pulmonary venography in another two. Using radiologic methods, including microradiography, and serial histologic sections, we found numerous bronchial venous plexuses around the airways and blood vessels into which the bronchial capillaries drained. Frequent communications of the venous plexuses with the pulmonary veins and neighboring alveolar capillaries were also demonstrated. The bronchial venous plexus and its close connection with the pulmonary circulation may be important in various pathologic conditions involving the interstitial space, such as interstitial pulmonary edema.  相似文献   
8.
9.
We have found that steroid bolus withdrawal prior to graft reperfusion increased the incidence of acute cellular rejection (ACR). This study aims to clarify how initial steroid bolus (ISB) injection at reperfusion influences the kinetics of CD8(+) alloreactive immune responses immediately after living donor liver transplantation (LDLT). A total of 49 hepatitis C virus (HCV)-infected recipients were classified into 3 groups according to hierarchical clustering by preoperative CD8(+)CD45 isoforms. The naive T cell proportion was considerably higher in Group I than in Groups II and III, whereas Group II recipients had the highest effector memory (EM) T cells and Group III the highest effector T cells. The frequency of ACR was significantly higher in recipients without ISB than in those with ISB. In particular, the ACR rates were the highest in Group II without ISB. Following ISB, the proportion of effector T cells was promptly upregulated within 6 hours after graft reperfusion, simultaneously with the upregulation of CD27(-)CD28(-) subsets, interferon-gamma (IFN-gamma), tumor necrosis factor-alpha and perforin expression, which significantly correlated with increasing interleukin (IL)-12 receptor beta 1 cells. These were then downregulated to below preoperative levels by tacrolimus (Tac) administered at 24 hours. These changes did not occur in the absence of ISB. In Group II without ISB, the downregulation of IL-12Rbeta1(+) cells was the greatest, consistent with the highest rates of ACR and mortality (60%). In conclusion, ISB must be done in place, especially in Group II with preexisting high EM T cells, to enable the development of early allograft acceptance.  相似文献   
10.
Humoral hypercalcemia of malignancy (HHM) in neoplastic syndrome has been most commonly reported in squamous cell carcinoma. Gallbladder carcinoma with HHM is uncommon. In this report, we describe a male case of gallbladder carcinoma with marked hypercalcemia and a high level of serum parathyroid hormone-related peptide (PTHrP). An immunohistochemical examination using PTHrP was also positive.  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