全文获取类型
收费全文 | 1994篇 |
免费 | 125篇 |
国内免费 | 9篇 |
专业分类
耳鼻咽喉 | 36篇 |
儿科学 | 98篇 |
妇产科学 | 17篇 |
基础医学 | 185篇 |
口腔科学 | 40篇 |
临床医学 | 215篇 |
内科学 | 611篇 |
皮肤病学 | 31篇 |
神经病学 | 98篇 |
特种医学 | 257篇 |
外科学 | 123篇 |
综合类 | 81篇 |
一般理论 | 8篇 |
预防医学 | 135篇 |
眼科学 | 32篇 |
药学 | 78篇 |
中国医学 | 10篇 |
肿瘤学 | 73篇 |
出版年
2022年 | 7篇 |
2021年 | 27篇 |
2020年 | 20篇 |
2019年 | 26篇 |
2018年 | 24篇 |
2017年 | 18篇 |
2016年 | 20篇 |
2015年 | 36篇 |
2014年 | 53篇 |
2013年 | 93篇 |
2012年 | 80篇 |
2011年 | 87篇 |
2010年 | 77篇 |
2009年 | 78篇 |
2008年 | 87篇 |
2007年 | 93篇 |
2006年 | 81篇 |
2005年 | 73篇 |
2004年 | 55篇 |
2003年 | 51篇 |
2002年 | 52篇 |
2001年 | 46篇 |
2000年 | 58篇 |
1999年 | 49篇 |
1998年 | 97篇 |
1997年 | 63篇 |
1996年 | 69篇 |
1995年 | 48篇 |
1994年 | 52篇 |
1993年 | 46篇 |
1992年 | 21篇 |
1991年 | 12篇 |
1990年 | 15篇 |
1989年 | 45篇 |
1988年 | 29篇 |
1987年 | 33篇 |
1986年 | 25篇 |
1985年 | 18篇 |
1984年 | 18篇 |
1983年 | 24篇 |
1982年 | 16篇 |
1981年 | 25篇 |
1980年 | 14篇 |
1979年 | 8篇 |
1978年 | 13篇 |
1977年 | 19篇 |
1976年 | 12篇 |
1975年 | 16篇 |
1969年 | 8篇 |
1935年 | 7篇 |
排序方式: 共有2128条查询结果,搜索用时 15 毫秒
1.
Jennifer Novak Yujie Cui Paul Frankel Mina S. Sedrak Scott Glaser Richard Li Sabin Motwani Brian Kavanagh Arya Amini 《Practical radiation oncology》2021,11(3):e263-e266
PurposeTwitter is an increasingly popular social media platform within the health care community. The objective of this analysis is to characterize the profile of radiation oncology–related tweets and Twitter users over the past 6 years.Methods and MaterialsUsing the web-based social media analytics platform Symplur Signals, we filtered tweets containing at least 1 of the following hashtags or key words: #radonc, #radiationoncology, "rad onc," or "radiation oncology." We evaluated radiation oncology–related Twitter activity between October 2014 and March 2020 for tweet frequency, tweet content, and individuals or groups posting tweets. We identified the most influential Twitter users contributing to radiation oncology–related tweets.ResultsFrom 2014 to 2020, the quarterly volume of radiation oncology–related tweets increased from 5027 to 29,763. Physicians contributed the largest growth in tweet volume. Academic radiation oncologists comprise 60% of the most influential Twitter accounts responsible for radiation oncology–related content. The number of radiation-oncology resident physicians on Twitter increased from 25 to 328 over the past 6 years, and 20% of radiation-oncology residency programs have a Twitter account. Seventy-one percent of radiation oncology–related tweets generated direct communication via mentions, and 59% of tweets contain links to external sources, including scientific articles.ConclusionsThe number of physicians contributing radiation oncology–related Twitter content has increased significantly in recent years. Academic radiation oncologists are the primary influencers of radiation oncology–related Twitter activity. Twitter is used by radiation oncologists to both professionally network and discuss findings related to the field. There remains the opportunity for radiation oncologists to broaden their audience on Twitter to encompass a more diverse community, including patients. 相似文献
2.
A 68 year-old woman presented with a two-week history of amaurosis fugax, ipsilateral fronto-temporal headache and jaw claudication suggesting carotid giant cell arteritis. However, this syndrome proved to be due to atherosclerosis causing complete occlusion of the external carotid artery at its origin and narrowing of the internal carotid artery. Combined external and internal carotid endarterectomy relieved the symptoms. The symptom complex of temporal arteritis may be rarely mimicked by carotid atherosclerotic occlusive disease. 相似文献
3.
A K Burroughs L Marelli E Cholongitas P Manousou K Rolles V Karam V Delvart R Adam C Sabin 《Liver transplantation》2007,13(6):935-6; author reply 937
4.
Summary A simple technique of stereotactic craniotomy and intraoperative lesion localisation that uses the Brown-Robert-Wells (BRW) stereotactic frame is presented. The method optimises craniotomy placement and facilitates localisation of small intracerebral lesions. Using the system, 16 patients have had resection of intracranial neoplasms from deep and/or eloquent areas of the brain with no neurological morbidity. 相似文献
5.
6.
目的 探讨创伤后迟发性脑肿胀的临床特点、发病机制与治疗。方法 回顾性分析1998年1月~2005年6月年收治的17例迟发性脑肿胀患者的临床特点和救治情况。结果 所有颅脑损伤患者采用保守治疗后均有好转,但于伤后5-10d出现恶化,CT复查有脑肿胀,经加强综合脱水等治疗后16例治愈,1例死亡。结论 迟发性脑肿胀好发于对冲性额、颞叶挫裂伤伴明显蛛网膜下腔出血、硬膜下薄层血肿及早期CT有脑肿胀者。其发病机制可能与创伤后的迟发性脑血管痉挛、微循环障碍、静脉回流障碍及甘露醇作用下降等因素有关。此类患者病情隐蔽性强,应加强观察、积极行CT复查,如能早期明确诊断,保守治疗多数效果良好。 相似文献
7.
Human C-reactive protein increases cerebral infarct size after middle cerebral artery occlusion in adult rats. 总被引:14,自引:0,他引:14
Ramanjit Gill John A Kemp Caroline Sabin Mark B Pepys 《Journal of cerebral blood flow and metabolism》2004,24(11):1214-1218
Human C-reactive protein (CRP), the classic acute phase plasma protein, increases in concentration after myocardial infarction and stroke. Human CRP binds to ligands exposed in damaged tissue and can then activate complement and its proinflammatory functions. In contrast, rat CRP, which binds to similar ligands, does not activate complement. In the present study, systemic complement depletion with cobra venom factor in adult rats subjected to middle cerebral artery occlusion did not affect cerebral infarct size, indicating that circulating complement does not contribute to injury in this model. However, we have previously reported that administration of human CRP to rats undergoing coronary artery ligation caused a marked increase in size of the resulting myocardial infarction, associated with codeposition of human CRP and rat complement in the infarcts. In the present study, we show that adult rats subjected to middle cerebral artery occlusion and then treated with human CRP similarly developed significantly larger cerebral infarcts compared with control subjects receiving human serum albumin. Human CRP can thus contribute to ischemic tissue damage in the brain as well as in the heart, and inhibition of CRP binding may therefore be a promising target for tissue protective acute therapeutic intervention in stroke as well as in myocardial infarction. 相似文献
8.
Retrorenal colon: implications for percutaneous diskectomy 总被引:1,自引:0,他引:1
It has been recommended that computed tomography (CT) with the patient prone be performed in every patient undergoing percutaneous diskectomy; this would enable detection of a retrorenal location of the colon, which could interfere with the percutaneous procedure. In this evaluation of 346 prone CT studies, only one patient (0.29%) was found to have retrorenal or retropsoas bowel that would have been perforated at diskectomy. Because of this extremely low prevalence, the performance of prone CT in every patient undergoing percutaneous lumbar diskectomy is not believed to be necessary. 相似文献
9.