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   118269篇
  免费   45115篇
  国内免费   2632篇
耳鼻咽喉   1948篇
儿科学   4973篇
妇产科学   1409篇
基础医学   19706篇
口腔科学   6051篇
临床医学   16889篇
内科学   28339篇
皮肤病学   7857篇
神经病学   15171篇
特种医学   3627篇
外国民族医学   14篇
外科学   18646篇
综合类   7768篇
现状与发展   8篇
一般理论   24篇
预防医学   7640篇
眼科学   2073篇
药学   9941篇
  45篇
中国医学   3644篇
肿瘤学   10243篇
  2024年   188篇
  2023年   792篇
  2022年   1880篇
  2021年   3716篇
  2020年   6793篇
  2019年   12130篇
  2018年   11483篇
  2017年   12776篇
  2016年   13290篇
  2015年   13910篇
  2014年   14287篇
  2013年   14892篇
  2012年   7720篇
  2011年   7625篇
  2010年   11398篇
  2009年   7267篇
  2008年   4480篇
  2007年   3128篇
  2006年   2948篇
  2005年   2468篇
  2004年   2034篇
  2003年   2026篇
  2002年   1899篇
  2001年   1643篇
  2000年   1400篇
  1999年   814篇
  1998年   314篇
  1997年   349篇
  1996年   250篇
  1995年   200篇
  1994年   210篇
  1993年   144篇
  1992年   215篇
  1991年   214篇
  1990年   185篇
  1989年   159篇
  1988年   143篇
  1987年   119篇
  1986年   94篇
  1985年   65篇
  1984年   50篇
  1983年   36篇
  1982年   22篇
  1981年   24篇
  1980年   32篇
  1979年   32篇
  1978年   23篇
  1977年   26篇
  1974年   15篇
  1970年   16篇
排序方式: 共有10000条查询结果,搜索用时 46 毫秒
41.
42.
1 The internal anal sphincter (IAS) has a spontaneous tone and is the main contributor to the maintenance of faecal continence. The spontaneous resting tone exhibited by the sphincter can be modified by neurotransmitters from the autonomic and enteric nervous systems. 2 In this review, the influence of the sympathetic and parasympathetic nervous systems on IAS tone are discussed and the putative roles of nitric oxide, carbon monoxide, vasoactive intestinal peptide and adenosine triphosphate in non‐adrenergic non‐cholinergic transmission are considered. 3 Faecal incontinence is a common condition that places a heavy financial burden on the health service and severely affects patients’ quality of life. Resting anal pressure is reduced in patients with faecal incontinence and agents that increase sphincter tone tend to relieve symptoms. The results of clinical studies of the use of phenylephrine to treat faecal incontinence are reviewed. 4 It is concluded that the IAS is a potential target for drug development for the treatment of faecal incontinence.  相似文献   
43.
目的 探讨内镜辅助肋骨-软骨移植重建髁突与同期正颌手术治疗严重颞下颌关节病变及牙颌面畸形的效果. 方法 于术前对患者进行临床检查和治疗设计,术中行Le Fort Ⅰ型截骨术、下颌支矢状骨劈开术、髁突等关节区病变的处理、内镜辅助下肋骨-软骨移植和颏成形术,术后进行随访. 结果 2003年9月至2005年12月,于临床应用15例,所有患者同期手术均顺利完成.术中、术后均无严重出血、神经损伤、受区感染等严重并发症发生.术后随访29~52个月,平均31.8个月,所有患者面容均显著改善,关节功能良好,且无关节区疼痛等主观症状,患者对手术疗效满意.术后张口度平均为33.6 mm,侧向运动度为0~6 mm. 结论 选择合适的适应证、设计合理的手术方案,内镜辅助髁突重建同期正颌手术效果较好.  相似文献   
44.
45.
Purpose Parathyroid carcinoma (PC) is rare and accounts for less than 1% of all cases of primary hyperparathyroidism (PHPT). The definitive histopathologic diagnosis of PC requires unequivocal invasion or metastasis which may be absent at first presentation. As a result, many cases of PC can only be diagnosed retrospectively. Parafibromin is the protein encoded by HRPT2 which is mutated and not expressed in many parathyroid carcinomas. Given that PCs generally weigh more than parathyroid adenomas (PA)s, we hypothesized that amongst large PAs there may be a high incidence of occult PC which could be identified by negative staining for parafibromin. Methodology 57 parathyroid glands weighing greater than 2 grams excised from 1998–2006 were identified from the University of Sydney Endocrine Surgical Database. Two specimens with a histopathologic diagnosis of PC were excluded. Immunohistochemical staining for parafibromin was performed on the remaining 55 PAs. Results Of the 55 specimens stained for parafibromin only one definite negative stain was detected. This case was originally classified as an “atypical adenoma” because it showed nuclear and architectural atypia without unequivocal evidence of invasive growth. In view of the negative staining for parafibromin it therefore probably represents occult carcinoma. There has been no evidence of recurrence or metastasis after 6.5 years. Conclusions Complete loss of staining for parafibromin is very rare in giant parathyroid adenomas suggesting that occult carcinoma is equally rare. As a result routine immunohistochemical staining for parafibromin does not appear to be an effective screening test for carcinoma in large PA without histopathologic features of PC.  相似文献   
46.
Purpose To demonstrate that laparoscopic adjustable gastric banding may promote oesophageal dilatation or interfere with oesophageal motility. Methodology We report a case of a 67 year old female with a complex medical history who developed secondary achalasia from a slipped laparoscopic adjustable gastric band for weight loss. This led to recurring episodes of aspiration pneumonia requiring multiple admissions at North Shore Hospital, Auckland, New Zealand. Results A decision was made to remove the gastric band, five years after its initial insertion. At one month follow up, she was swallowing normally and oesophageal manometry had returned to normal. Conclusion Oesophageal dysmotility is sometimes seen in patients who have bands that are adjusted too tightly or in whom the band has slipped. This can lead to serious complications if unrecognized and incorrectly treated. Oesophageal symptoms in patients with adjustable bands must be considered secondary to the band until proven otherwise ie removal of the band or complete deflation.  相似文献   
47.
目的探讨肥胖与结石病发病的关系。方法采用调查表的方式对1997年住院手术确诊为结石病的病人进行回顾性调查,内容包括:年龄、性别、体重、身高、是否吃早餐。对调查表进行多因素logstic统计分析。结果分析结果表明我们调查了我院102例结石病患者和101名正常人发现肥胖、女性、不经常吃早餐、饮用高硬度的水均是结石病的危险因紊,对那些长时间不吃早餐的人更容易患结石病,(相对危险度OR〉40.139)。结论我们建议今后应注意膳食营养的均衡,保持标准体重,饮用卫生水。  相似文献   
48.
49.
50.
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