全文获取类型
收费全文 | 2071篇 |
免费 | 135篇 |
国内免费 | 26篇 |
专业分类
耳鼻咽喉 | 28篇 |
儿科学 | 57篇 |
妇产科学 | 71篇 |
基础医学 | 206篇 |
口腔科学 | 42篇 |
临床医学 | 224篇 |
内科学 | 311篇 |
皮肤病学 | 63篇 |
神经病学 | 113篇 |
特种医学 | 251篇 |
外科学 | 224篇 |
综合类 | 74篇 |
预防医学 | 158篇 |
眼科学 | 13篇 |
药学 | 172篇 |
肿瘤学 | 225篇 |
出版年
2023年 | 11篇 |
2022年 | 24篇 |
2021年 | 43篇 |
2020年 | 24篇 |
2019年 | 28篇 |
2018年 | 35篇 |
2017年 | 28篇 |
2016年 | 41篇 |
2015年 | 43篇 |
2014年 | 59篇 |
2013年 | 84篇 |
2012年 | 107篇 |
2011年 | 106篇 |
2010年 | 89篇 |
2009年 | 83篇 |
2008年 | 88篇 |
2007年 | 104篇 |
2006年 | 105篇 |
2005年 | 74篇 |
2004年 | 78篇 |
2003年 | 60篇 |
2002年 | 67篇 |
2001年 | 57篇 |
2000年 | 61篇 |
1999年 | 52篇 |
1998年 | 62篇 |
1997年 | 48篇 |
1996年 | 48篇 |
1995年 | 40篇 |
1994年 | 23篇 |
1993年 | 28篇 |
1992年 | 28篇 |
1991年 | 25篇 |
1990年 | 35篇 |
1989年 | 36篇 |
1988年 | 34篇 |
1987年 | 36篇 |
1986年 | 39篇 |
1985年 | 30篇 |
1984年 | 15篇 |
1983年 | 13篇 |
1982年 | 17篇 |
1981年 | 8篇 |
1980年 | 11篇 |
1978年 | 10篇 |
1977年 | 10篇 |
1976年 | 11篇 |
1975年 | 11篇 |
1974年 | 7篇 |
1973年 | 10篇 |
排序方式: 共有2232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.
3.
4.
5.
R. J. Rona A. V. Swan R. Beech D. M. Wilson F. B. Kavanagh C. Brown C. Axtell S. Mandalia 《Clinical genetics》1992,42(4):186-195
For certain genetic conditions DNA testing identifies carriers and determines the risk status of foetuses, thus helping parents to make more informed prenatal decisions. Data, collected from three genetic centres in England and Wales from August 1986 to July 1990, are used to describe trends in demand for DNA testing, the impact of DNA tests on carrier risk assessment, and the use of DNA tests in relation to pregnancy outcome. Altogether the data include 23,388 subjects and 681 pregnancies in 8738 families divided into five cohorts by year of entry and referral. The most frequent gene disorders referred to the genetic centres are currently being tested or will soon be tested. For these disorders the initial high level of activity has declined and may have reached steady state. Demand for DNA services is high for cystic fibrosis and Duchenne muscular dystrophy, intermediate for Huntington's disease, and low for adult polycystic kidney disease, phenylketonuria and tuberous sclerosis. Based on these findings we suggest that demand for DNA tests will be high in serious, untreatable and slow progressing conditions with early onset; intermediate for conditions affecting intellect and neurological integrity with later onset; and low for treatable, late-onset conditions, or those for which there is evidence of heterogeneity, and variable penetrance. It would be helpful to assess the extent to which this view of demand is confirmed when the new disorders being DNA tested are considered and for the pattern of activity of DNA testing for some types of cancer. Since no DNA centre could offer a fully comprehensive testing service, it is recommended that a structure is created to audit overall activity, assist in policy formulation, and influence supraregional service organisation, in order that the spread of DNA services be planned as effectively as possible. This structure would facilitate monitoring of the evolution of contract specifications agreed by commissioners and providers on a regional basis. 相似文献
6.
7.
8.
Further experience with radiation therapy and concomitant intravenous chemotherapy in advanced carcinoma of the lower female genital tract 总被引:4,自引:1,他引:3
William S. Roberts M.D. Mitchel S. Hoffman M.D. John J. Kavanagh M.D. James V. Fiorica M.D. Harvey Greenberg M.D. Michael A. Finan M.D. Denis Cavanagh M.D. 《Gynecologic oncology》1991,43(3):233-236
Sixty-seven patients with advanced carcinoma of the lower female genital tract (cervix, vagina, and vulva) were treated with radiation and concomitant intravenous cisplatin and/or 5-fluorouracil. Fifty-seven patients (85%) responded completely clinically. Thirty-five (61%) complete responders recurred with a median time to recurrence of 6 months. Twenty-six of the thirty-five patients who recurred had some component of local failure. The 22 complete responders who have not recurred have been followed a median of 13 months. Acute toxicity was minimal, with only 6 patients requiring interruption of therapy. Nine (13%) patients developed severe late complications and eight required surgery. The actuarial 5-year survival is 22%. This treatment regimen is disappointing in terms of both survival and local control. 相似文献
9.
Kinnison ML; Perler BA; Kaufman SL; Mitchell SE; Kadir S; Williams GM; White RI Jr 《Radiology》1986,160(3):727-730
In situ saphenous vein grafts are being used with increasing frequency for bypass procedures involving the femoral and popliteal arteries. Complications of these procedures include anastomotic stenoses and persistent arteriovenous fistulae that may result in failure of the graft. Balloon angioplasty and embolotherapy with detachable balloons were employed successfully in three or four recent cases of patients with complications from in situ grafts. Tailored angiography is essential for evaluating in situ grafts, and interventional techniques are extremely useful for managing complications. 相似文献
10.