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   94465篇
  免费   9205篇
  国内免费   5260篇
耳鼻咽喉   1034篇
儿科学   1581篇
妇产科学   915篇
基础医学   9612篇
口腔科学   1935篇
临床医学   10661篇
内科学   13497篇
皮肤病学   1563篇
神经病学   4781篇
特种医学   4321篇
外国民族医学   30篇
外科学   10185篇
综合类   16100篇
现状与发展   13篇
一般理论   9篇
预防医学   7260篇
眼科学   2562篇
药学   9944篇
  57篇
中国医学   6113篇
肿瘤学   6757篇
  2024年   333篇
  2023年   1285篇
  2022年   3305篇
  2021年   4449篇
  2020年   3401篇
  2019年   2944篇
  2018年   3083篇
  2017年   3089篇
  2016年   3078篇
  2015年   4409篇
  2014年   5466篇
  2013年   5869篇
  2012年   8324篇
  2011年   8430篇
  2010年   6243篇
  2009年   5273篇
  2008年   6056篇
  2007年   5802篇
  2006年   5415篇
  2005年   4593篇
  2004年   3721篇
  2003年   3315篇
  2002年   2699篇
  2001年   1919篇
  2000年   1445篇
  1999年   1109篇
  1998年   597篇
  1997年   640篇
  1996年   443篇
  1995年   371篇
  1994年   352篇
  1993年   216篇
  1992年   198篇
  1991年   200篇
  1990年   155篇
  1989年   134篇
  1988年   108篇
  1987年   93篇
  1986年   82篇
  1985年   48篇
  1984年   37篇
  1983年   34篇
  1982年   17篇
  1981年   23篇
  1980年   14篇
  1979年   24篇
  1978年   10篇
  1977年   8篇
  1976年   9篇
  1974年   12篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
11.
肺隔离症的影像诊断和介入治疗   总被引:9,自引:1,他引:8  
目的探讨肺隔离症的影像学表现及介入治疗的应用价值. 资料与方法对5例肺隔离症患者的X线平片、CT、MRI表现进行分析,并对隔离的肺组织的供血动脉进行栓塞. 结果 X线平片主要表现为囊状或团状高密度影及支气管扩张样改变,CT、MRI可发现部分异常供血动脉,血管造影均能发现供血动脉,经异常供血动脉采用不锈钢圈栓塞后临床症状逐渐减轻、消失,随访6个月~1年,症状未再复发. 结论在影像诊断方面,X线平片难以确诊,CT、MRI可部分确诊,而DSA检查是肺隔离症诊断的金标准.经异常供血动脉栓塞治疗肺隔离症安全,患者痛苦小,并发症少,是一种有效的治疗方法.  相似文献   
12.
Penetrating craniocerebral firearm injuries remain one of the most lethal causes of all trauma and are common both in war or peace time. Data were reviewed for 4140 severely head-injured patients (Glasgow Coma Scale (GCS) scores 3-8) treated at Xi-Jing Hospital between 1973 and 1993; 51 of these patients had acute penetrating craniocerebral injuries caused by firearm missiles. These patients consisted of 46 males (90.2%) and 5 females (9.8%) ranging in age from 3 months to 48 years (median 22.4 years). The lesion types included 2 tangential wounds, 37 tubular wounds and 12 through-and-through wounds. All cases were urgent with the patients in severe and unstable states. After emergency treatment and operation, 5 cases died (9.8%). Follow up studies at three months showed that 23 cases (45.1%) had made a good recovery. Moderate disability, severe disability and vegetative states in this series were 29.4%, 13.7% and 2.0% respectively. Long term follow up studies indicated that 32 were able to resume their occupation. The principles for managing penetrating craniocerebral firearm injuries and suggestions for operation are discussed.  相似文献   
13.
本文报告了1990年5月以来脑干区大型、复杂占位病变15例.其中,位于脑干内3例,脚间窝2例,岩尖部4例,全岩骨区1例,全斜坡区2例,第四脑室内3例.本组采用以扩大了的岩骨入路为主的联合入路,行肿瘤全切除8例,次全切除5例.2例仅作了活检加减压术.除1例死亡外,均恢复良好.本文结合文献,对脑干区手术入路进行了讨论.  相似文献   
14.
Abstract: Juvenile xanthogranuloma is a xanthomatous and granulomatous condition that frequently arises before 1 year of age and mainly occurs on the head and trunk. We report a rare solitary juvenile xanthogranuloma on the right palm of a 10-year-old girl, present for one year. This solitary involvement of the palm has been reported only twice before.  相似文献   
15.
16.
The value of ventilation scintigraphy after single lung transplantation.   总被引:1,自引:0,他引:1  
BACKGROUND: A decrease in forced expiratory volume in 1 second (FEV(1)) as a diagnostic criterion for bronchiolitis obliterans syndrome (BOS) after single lung transplantation may be influenced significantly by the presence of the native lung. To quantify and to discriminate between the relative contribution of graft and native lung to the FEV(1), we retrospectively investigated the diagnostic value of combined FEV(1) measurements and ventilation scintigraphy in pulmonary dysfunction after single lung transplantation in 11 recipients with pulmonary vascular disease, 3 with obstructive lung disease, and 3 with restrictive lung disease. METHODS: We assessed function of the native lung and the graft, and subsequently calculated an adjusted grading of BOS by correcting routine FEV(1) measurements using linear interpolation of bi-annual lung ventilation scans. RESULTS: The contribution of the native lung to the total FEV(1) was slight (median, 9%) in recipients with obstructive disease compared with recipients with vascular (38%) or restrictive lung diseases (27%). Adjusted BOS grading was not useful in patients with obstructive disease. In the other patient groups, the onset of adjusted BOS Grade 1 and standard BOS Grade 1 was at a median of 220 days (range, 127-1146 days) and 836 days (184-3065 days), respectively. CONCLUSION: Ventilation scintigraphy is a useful adjunct in the (early) diagnosis of BOS in recipients of single lung transplants who have vascular and restrictive lung diseases.  相似文献   
17.
移植肾破裂的处理   总被引:4,自引:0,他引:4  
目的 提高移植肾破裂的防治水平。方法  6例移植肾破裂 ,手术前 2例 ,手术后 4例。 2例术前供肾破裂 ,采用切开移植肾破裂处包膜 +裂口内明胶海绵填塞 +肠线修补 +肠线编织肾袋收缩保护移植肾。 1例术后移植肾破裂早期 ,出血少 ,针对顽固性高血压采用“硝普钠”降压 ,配合常规抗排斥药物。 3例术后移植肾破裂出血量估计超过 10 0 0ml者 ,采用手术延长移植肾破裂处包膜 +裂口内明胶海绵填塞 +肠线修补 +肠线编织肾袋收缩保护移植肾。结果  ( 1)手术前 2例手术后 4例 ,采用切开或者延长移植肾破裂处包膜 +裂口内明胶海绵填塞 +肠线修补 +肠线编织肾袋收缩保护移植肾并配合“硝普钠”降压的方法处理 ,均未再破裂出血 ,移植肾功能恢复良好。 ( 2 ) 1例术后移植肾破裂早期的患者 ,针对顽固性高血压采用“硝普钠”降压 ,配合常规抗排斥药物 ,非手术治疗成功。结论  ( 1)采用手术切开或延长移植肾破裂处包膜 +裂口内明胶海绵填塞 +肠线修补 +肠线编织肾袋收缩保护移植肾可以有效治疗移植肾破裂。 ( 2 )移植肾破裂出血少的情况下 ,可以在密切观察下非手术治疗  相似文献   
18.
The operating department nurse is subject to many stressors and while there is an optimum level of stress where nurses function at their best, too much may be detrimental both to nurses--and their patients. Jean Sang looks at the subject of stress and discusses the findings of her research.  相似文献   
19.
Conventional computerized tomography (CT) technique is based on the absorption contrast. In recent years, X-ray phase-contrast CT (PCCT) has been developing rapidly. It uses the phase information to reconstruct the object and provide high contrast and spatial resolution. Diffraction enhanced imaging (DEI) method is one of the three phase-sensitive X-ray imaging techniques. DEI method employs an analyzer crystal to extract the object's refraction information which can be used for CT. However, when DEI refraction CT is combined with the conventional CT algorithm, it should be satisfied that the refraction information of an arbitrary point in the object is invariable at every projection view. In this paper, the invariance condition of refraction information is analyzed and two feasible methods are provided for reconstruction. Using these two methods, two samples of weak absorption are reconstructed with the experimental data obtained at Beijing Synchrotron Radiation Facility (BSRF).  相似文献   
20.
本研究用酶联免疫吸附术观察8只家兔在附睾注射鱼肝油酸钠后血清及精浆中的抗精子抗体。血清抗精子抗体阳性率为37.5~50.0%,最早检出率为术后2个月,6~7月达高峰。精浆抗精子抗体阳性率为25%,最早检出率为术后4个月,且此时己达高峰。与输精管结扎资料相比,发现血清抗精子抗体检出率偏低,而精浆相应抗体偏高,表明向附睾注射鱼肝油酸钠引起的免疫反应有别于结扎,以生殖道局部为主。  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