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   35546篇
  免费   2978篇
  国内免费   1541篇
耳鼻咽喉   331篇
儿科学   492篇
妇产科学   397篇
基础医学   5601篇
口腔科学   3029篇
临床医学   4534篇
内科学   4491篇
皮肤病学   714篇
神经病学   1524篇
特种医学   1691篇
外国民族医学   8篇
外科学   5340篇
综合类   4765篇
现状与发展   10篇
预防医学   1025篇
眼科学   531篇
药学   2279篇
  10篇
中国医学   1162篇
肿瘤学   2131篇
  2024年   77篇
  2023年   541篇
  2022年   803篇
  2021年   1164篇
  2020年   1254篇
  2019年   1199篇
  2018年   1240篇
  2017年   1169篇
  2016年   1213篇
  2015年   1275篇
  2014年   2286篇
  2013年   3203篇
  2012年   1954篇
  2011年   2282篇
  2010年   1745篇
  2009年   1778篇
  2008年   1841篇
  2007年   1882篇
  2006年   1670篇
  2005年   1537篇
  2004年   1331篇
  2003年   1146篇
  2002年   851篇
  2001年   783篇
  2000年   584篇
  1999年   550篇
  1998年   435篇
  1997年   425篇
  1996年   375篇
  1995年   334篇
  1994年   300篇
  1993年   230篇
  1992年   248篇
  1991年   233篇
  1990年   198篇
  1989年   180篇
  1988年   178篇
  1987年   159篇
  1986年   131篇
  1985年   184篇
  1984年   141篇
  1983年   109篇
  1982年   135篇
  1981年   142篇
  1980年   124篇
  1979年   88篇
  1978年   74篇
  1977年   57篇
  1976年   77篇
  1975年   30篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
21.
Granulomatous slack skin is an indolent T-cell lymphoma, considered to be a variant of mycosis fungoides. Clinically it is characterized by areas of redundant skin, wrinkled, inelastic, with variable erythema and infiltration besides a poikilodermic surface. A differential diagnosis unknown to most dermatologists is the giant cell tumor of soft tissue, which is an extremely rare low-grade sarcoma. The authors report a patient who had undergone extensive surgery because of a primary diagnosis of giant cell tumor of soft tissue, but which proved to be granulomatous slack skin after a second interventional procedure with confirmatory histopathology.  相似文献   
22.
23.
《Clinical neurophysiology》2019,130(9):1562-1569
ObjectiveConventional deep brain stimulation (DBS) systems with ring-shaped leads generate spherical electrical fields. In contrast, novel directional leads use segmented electrodes. Aim of this study was to quantify the impedance variations over time in subjects with the directional Cartesia-Boston® system.MethodsImpedance records, programming settings, and clinical data of 11 consecutive Parkinsonian patients implanted with DBS directional leads in two Italian centers (Udine and Vicenza) were retrospectively evaluated. Data were collected before starting stimulation (in the operating room and at days 5 and 40) and after switching stimulation on at the successive follow-up visits (1, 6 and 12 months).ResultsDirectional leads have significantly higher impedance than ring leads. Stimulated contacts had always lower impedance compared to non-stimulated contacts. Before DBS-on, all contacts had higher impedance in the operating room, with an initial decrease five days post-surgery and a subsequent increase at day 40, more evident for directional contacts. The impedance of directional leads increased post-implantation at 1 and 6 months with a plateau at 12 months.ConclusionsThere was a significant difference between the directional and ring leads at baseline (before activation of DBS) and during follow-up (chronic DBS).SignificanceOur study reveals new information about the impedance of segmented electrodes that is useful for patient management during the initial test period, as well as during long-term DBS follow-up.  相似文献   
24.
Bone containing tissues such as osteochondral joint are resistant to routine tissue processing, therefore require decalcification. This technique causes removal of mineral salts, but in the process may macerate the organic tissue, hence the need for tissue fixation. Such severe processing demands careful antigen retrieval to necessitate optimal staining. The aim of our study was to compare five different antigen retrieval protocols (heat retrieval and protein digestion) following decalcification of rabbit knee joints using two different techniques (20% formic acid and 10% ethylenediamine-tetra acetic acid: EDTA). Osteochondral sections were compared based on time required for decalcification, ease of sectioning, morphological integrity using HE staining and antigen preservation (Collagen type II) using immunohistochemistry. The two decalcification solutions did not impair the tissue morphology and ease of sectioning. Joints processed with formic acid decalcified four times faster than EDTA. Among the five antigen retrieval approaches, maximal collagen II uptake with minimal nonspecific staining was found with protein digestion (pronase and hyaluronidase) in both formic acid and EDTA sections. For osteo-chondral sections, we recommend using 10% EDTA for decalcification and pronase plus hyaluronidase for antigen retrieval if maintaining tissue morphology is crucial, whereas if time is of the essence, 20% FA with pronase plus hyaluronidase is the faster option while still preserving structural integrity. Clin. Anat. 33:343–349, 2020. © 2019 Wiley Periodicals, Inc.  相似文献   
25.
26.
27.
28.
29.
30.
目的探讨胫前动脉踝上穿支皮瓣修复足踝部软组织缺损的临床疗效。方法回顾性研究2018年4月至2019年6月采用胫前动脉踝上穿支皮瓣修复足踝部软组织缺损19例的资料,其中男11例,女8例;年龄为21~75岁,平均39岁。根据前踝上穿支皮瓣解剖学基础,按照足踝部软组织缺损大小和形状,在小腿下端前外侧设计并切取皮瓣转位修复创面。切取胫前动脉踝上穿支皮瓣面积为6.0 cm×5.0 cm^14.0 cm×8.0 cm,均为带蒂皮瓣转位。根据皮瓣成活、感染控制、弹性色泽、外观形态、供区瘢痕、皮肤感觉、患者认可等情况,对患者足踝部软组织缺损的修复情况进行综合评价。结果本组19例皮瓣全部成活,软组织缺损、肌腱、骨质及钢板外露均得以修复。供区均I期愈合。术后门诊随访2~16个月,皮瓣血运良好,颜色接近周围正常皮肤,臃肿不明显,患者对外观表示满意;供区皮片愈合良好,无明显增生、挛缩及溃疡,踝关节功能良好。结论胫前动脉踝上穿支皮瓣是修复足踝部软组织缺损较为理想的方法之一,手术操作简便,穿支较恒定,血供可靠,具有一定的临床应用价值。  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