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   63993篇
  免费   4089篇
  国内免费   268篇
耳鼻咽喉   830篇
儿科学   1345篇
妇产科学   854篇
基础医学   8422篇
口腔科学   1489篇
临床医学   6368篇
内科学   13805篇
皮肤病学   1334篇
神经病学   6852篇
特种医学   3400篇
外国民族医学   10篇
外科学   10640篇
综合类   403篇
一般理论   15篇
预防医学   3301篇
眼科学   920篇
药学   3965篇
中国医学   91篇
肿瘤学   4306篇
  2023年   471篇
  2022年   769篇
  2021年   1634篇
  2020年   968篇
  2019年   1447篇
  2018年   1676篇
  2017年   1322篇
  2016年   1607篇
  2015年   1838篇
  2014年   2295篇
  2013年   2836篇
  2012年   4532篇
  2011年   4590篇
  2010年   2678篇
  2009年   2454篇
  2008年   3970篇
  2007年   4057篇
  2006年   3807篇
  2005年   3807篇
  2004年   3392篇
  2003年   3264篇
  2002年   2983篇
  2001年   1041篇
  2000年   930篇
  1999年   914篇
  1998年   680篇
  1997年   527篇
  1996年   443篇
  1995年   349篇
  1994年   345篇
  1993年   287篇
  1992年   466篇
  1991年   432篇
  1990年   420篇
  1989年   389篇
  1988年   357篇
  1987年   309篇
  1986年   302篇
  1985年   292篇
  1984年   293篇
  1983年   238篇
  1982年   181篇
  1981年   148篇
  1979年   203篇
  1978年   162篇
  1977年   140篇
  1976年   134篇
  1975年   155篇
  1974年   151篇
  1973年   138篇
排序方式: 共有10000条查询结果,搜索用时 20 毫秒
51.
The authors present a case of amyloid infiltration involving the trigeminal nerve that mimicked a malignant cavernous sinus tumor with perineural tumor infiltration. A 64-year-old man presented with trigeminal nerve numbness. Imaging revealed a plaque-like enhancing lesion along the right lateral cavernous sinus extending anteriorly into Meckel's cave and involving the proximal V2 and V3 branches of the trigeminal nerve. The patient underwent an extradural frontotemporal craniotomy with middle fossa exposure of the cavernous sinus to diagnose and treat the presumed malignant cavernous sinus tumor. A reddish mass involving the lateral dural wall of the cavernous sinus was resected. The gasserian ganglion, V2, and V3, the latter of which was biopsied, were enlarged. Permanent histopathological studies showed microscopic eosinophilic, amorphous material, which stained positive for Congo red, and an absence of neoplastic cells. The final diagnosis was amyloidoma. Thus, amyloidomas can involve the trigeminal nerve or ganglia and should be considered in the differential diagnosis of a cavernous sinus lesion mimicking a tumor. Patients may have symptomatic improvement of trigeminal neuropathy with resection of the amyloidoma outside the nerve capsule that is compressing the nerve, while resection of the lesion from within the capsule may result in permanent trigeminal nerve dysfunction.  相似文献   
52.
53.
In order to establish a venom fingerprint and a peptide profile of the Lasiodora parahybana tarantula venom gland, we used conventional methods such as reversed phase liquid chromatography coupled to an electrospray-ionisation hybrid quadrupole time of flight mass spectrometer (LC/ESI-QqTOFMS), matrix-assisted laser desorption/ionization time-of-flight-MS (MALDI-TOFMS) and direct study of L. parahybana venom by nanospray-ionization QqTOFMS (nanoESI-QqTOFMS) and a new technology for the direct analysis of fresh tissues using MALDI-TOFMS. The analysis of the crude venom allowed the characterization of specific juvenile and adult biomarkers. In situ MALDI analysis of L. parahybana venom gland sections revealed different peptide expression levels all along the gland and non-processed peptide precursors, demonstrating the power of the method for the dynamic investigation of peptide evolution in the venom gland of spiders.  相似文献   
54.
This case demonstrates that hysteroscopic polypectomy can enhance fertility. A 35-year-old woman was being evaluated for assisted conception. She was referred from an in vitro fertilisation clinic for polypectomy, which she had undergone on two occasions. She conceived spontaneously, had an uneventful antenatal period, and delivered a healthy baby at 39 weeks' gestation.  相似文献   
55.
Working memory after severe traumatic brain injury.   总被引:1,自引:0,他引:1  
The aim of the present study was to assess the functioning of the different subsystems of working memory after severe traumatic brain injury (TBI). A total of 30 patients with severe chronic TBI and 28 controls received a comprehensive assessment of working memory addressing the phonological loop (forward and backward digit span; word length and phonological similarity effects), the visuospatial sketchpad (forward and backward visual spans), and the central executive (tasks requiring simultaneous storage and processing of information, dual-task processing, working memory updating). Results showed that there were only marginal group differences regarding the functioning of the two slave systems, whereas patients with severe TBI performed significantly poorer than controls on most central executive tasks, particularly on those requiring a high level of controlled processing. These results suggest that severe TBI is associated with an impairment of executive aspects of working memory. The anatomic substrate of this impairment remains to be elucidated. It might be related to a defective activation of a distributed network, including the dorsolateral prefrontal cortex.  相似文献   
56.
Abstract Objective: To define the diagnostic accuracy of clinical examination in patients with impaired consciousness or endotracheal intubation to detect pelvic ring fractures and to identify those with severe bleeding. Methods: Included in this prospective data collection with retrolective data analysis were a consecutive series of blunt trauma victims with either a Glasgow Coma Scale ≤ 13 or tracheal intubation. Clinical examination comprised testing for stability of the iliac wings. Results: From 784 subjects (injury severity score 23.3 ± 17.4) 93 patients (11.9%) were found to have a pelvic ring fracture. Clinical instability of the pelvic ring was found in 42 patients. There was only one false positive. Fifty-two fractures could not be identified by clinical examination, including nine fractures (17%) that required surgical fracture stabilization (sensitivity of clinical examination 44.1%). Seventeen fractures (18.3%) were associated with a blood loss larger than 20% of circulating blood volume. Sixteen of those were identified by clinical instability of the pelvic ring (sensitivity 94.1%, specificity 97.0%, positive predictive value 38.1%, negative predictive value 99.9%). Conclusions: Clinical examination for stability of the pelvis in this selected group of patients missed a significant number of pelvic ring fractures including fractures that require surgical stabilization. The finding of a clinically unstable identifies most of the patients with the pelvic ring fracture being a major source of bleeding. A stable pelvis makes pelvic ring fracture as being the source of bleeding quite unlikely.  相似文献   
57.

Introduction  

Planning human resources for health (HRH) is a complex process for policy-makers and, as a result, many countries worldwide swing from surplus to shortage. In-depth case studies can help appraising the challenges encountered and the solutions implemented. This paper has two objectives: to identify the key challenges in HRH planning in Belgium and to formulate recommendations for an effective HRH planning, on the basis of the Belgian case study and lessons drawn from an international benchmarking.  相似文献   
58.
With 1–1.5 million cases reported every year cutaneous leishmaniasis represents an increasing health problem. The course of cutaneous leishmaniasis varies from a single self‐healing ulcer to a persistent ulcer or progressive mucosal disease with nasopharyngeal destruction. An enormous array of topical and systemic treatment modalities has been endorsed. The response to treatment depends on the species of parasite as well as the host's immunological and genetic status. Species‐specific treatment guidelines based on evidence from controlled studies are highly desirable. We present two cases of cutaneous leishmaniasis, one in a child and one during pregnancy, reviewing various diagnostic and therapeutic measures with special attention to problems in young and pregnant patients.  相似文献   
59.
60.
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