全文获取类型
收费全文 | 1609366篇 |
免费 | 128526篇 |
国内免费 | 4133篇 |
专业分类
耳鼻咽喉 | 20509篇 |
儿科学 | 51745篇 |
妇产科学 | 44835篇 |
基础医学 | 225676篇 |
口腔科学 | 41631篇 |
临床医学 | 146881篇 |
内科学 | 325803篇 |
皮肤病学 | 36222篇 |
神经病学 | 137407篇 |
特种医学 | 62619篇 |
外国民族医学 | 477篇 |
外科学 | 241539篇 |
综合类 | 34961篇 |
现状与发展 | 4篇 |
一般理论 | 655篇 |
预防医学 | 124446篇 |
眼科学 | 36380篇 |
药学 | 111988篇 |
2篇 | |
中国医学 | 3636篇 |
肿瘤学 | 94609篇 |
出版年
2021年 | 15250篇 |
2019年 | 15844篇 |
2018年 | 21630篇 |
2017年 | 16456篇 |
2016年 | 18408篇 |
2015年 | 20796篇 |
2014年 | 29600篇 |
2013年 | 43096篇 |
2012年 | 59936篇 |
2011年 | 63116篇 |
2010年 | 36745篇 |
2009年 | 34979篇 |
2008年 | 57857篇 |
2007年 | 61062篇 |
2006年 | 61300篇 |
2005年 | 59660篇 |
2004年 | 56786篇 |
2003年 | 53628篇 |
2002年 | 51628篇 |
2001年 | 74687篇 |
2000年 | 75763篇 |
1999年 | 63288篇 |
1998年 | 19373篇 |
1997年 | 17329篇 |
1996年 | 17214篇 |
1995年 | 16307篇 |
1994年 | 14752篇 |
1993年 | 13892篇 |
1992年 | 46691篇 |
1991年 | 44294篇 |
1990年 | 42154篇 |
1989年 | 40172篇 |
1988年 | 36760篇 |
1987年 | 35883篇 |
1986年 | 33419篇 |
1985年 | 31883篇 |
1984年 | 24606篇 |
1983年 | 20715篇 |
1982年 | 13114篇 |
1981年 | 11620篇 |
1979年 | 21122篇 |
1978年 | 15037篇 |
1977年 | 12482篇 |
1976年 | 11738篇 |
1975年 | 11904篇 |
1974年 | 14262篇 |
1973年 | 13773篇 |
1972年 | 12788篇 |
1971年 | 11612篇 |
1970年 | 11010篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
181.
Emile Gogineni Zaker Rana Michael Wotman Jessie Karten Adam Riegel Mihaela Marrero Luis Maduro Dev Kamdar Douglas Frank Doru Paul Nagashree Seetharamu Maged Ghaly 《Journal of Geriatric Oncology》2021,12(1):122-127
PurposeManagement of head and neck cancers (HNC) in older adults is a common but challenging clinical scenario. We assess the impact of Stereotactic Body Radiation Therapy (SBRT) on survival utilizing the Geriatric-8 (G8) questionnaire.Materials and methods171 HNC patients, deemed medically unfit for definitive treatment, were treated with SBRT ± systemic therapy. G8 questionnaires were collected at baseline, at 4–6 weeks, and at 2–3 months post-treatment. Patients were stratified according to their baseline G8 score: <11 as ‘vulnerable’, 11–14 as ‘intermediate’, and >14 as ‘fit’. Overall survival (OS) was assessed through univariate Kaplan Meier analysis. Repeated measures ANOVA was used to determine if baseline characteristics affected G8 score changes.ResultsMedian follow-up was seventeen months. 60% of patients presented with recurrent HNC, 30% with untreated HNC primaries, and 10% with metastatic non-HNC primaries. Median age was 75 years. Median Charlson Comorbidity Index score was 2. 51% of patients were ‘vulnerable’, 37% were ‘intermediate’, and 12% were ‘fit' at baseline, with median survival of 13.2, 24.3, and 41.0 months, respectively (p = .004). Patients who saw a decrease in their follow-up G8 score (n = 69) had significantly lower survival than patients who had stable or increased follow-up G8 scores (n = 102), with median survival of 8.6 vs 36.0 months (p < .001).ConclusionThe G8 questionnaire may be a useful tool in upfront treatment decision-making to predict prognosis and prevent older patients from receiving inappropriate anti-cancer treatment. Decline in follow-up G8 scores may also predict worse survival and aid in goals of care following treatment. 相似文献
182.
183.
184.
Victoria A. Chang Dawn M. Meyer Brett C. Meyer 《Journal of stroke and cerebrovascular diseases》2019,28(1):163-166
Background
Acute stroke codes may be activated for anisocoria, but how often these codes lead to a final stroke diagnosis or alteplase treatment is unknown. The purpose of this study was to assess the frequency of anisocoria in stroke codes that ultimately resulted in alteplase administration.Methods
We retrospectively assessed consecutive alteplase-treated patients from a prospectively-collected stroke registry between February 2015 and July 2018. Based on the stroke code exam, patients were categorized as having isolated anisocoria [A+(only)], anisocoria with other findings [A+(other)], or no anisocoria [A?]. Baseline demographics, stroke severity, alteplase time metrics, and outcomes were also collected.Results
Ninety-six patients received alteplase during the study period. Of the 94 who met inclusion criteria, there were 0 cases of A+(only). There were 9 cases of A+(other) (9.6%). A+(other) exhibited higher baseline National Institutes of Health (NIH) Stroke Scale scores compared to A? (17 versus 7; P?=?.0003), and no additional differences in demographics or alteplase time metrics. Final stroke diagnosis and other outcome measures were no different between A+(other) and A?. Of the A+ patients without pre-existing anisocoria, 5 of 6 (83%) had posterior circulation events or diffuse subarachnoid hemorrhage.Conclusions
In this exploratory analysis, zero patients with isolated anisocoria received alteplase treatment. Anisocoria as a part of the neurologic presentation occurred in 10% of alteplase patients, and was strongly associated with a posterior circulation event. Therefore, we conclude that anisocoria has a higher likelihood of leading to alteplase treatment when identified in the presence of other neurologic deficits. 相似文献185.
Ramya C. Mosarla Muthiah Vaduganathan Arman Qamar Javid Moslehi Gregory Piazza Robert P. Giugliano 《Journal of the American College of Cardiology》2019,73(11):1336-1349
Patients with active cancer are at an increased risk of arterial and venous thromboembolism (VTE) and bleeding events. Historically, in patients with cancer, low molecular weight heparins have been preferred for treatment of VTE, whereas warfarin has been the standard anticoagulant for stroke prevention in patients with atrial fibrillation (AF). More recently, direct oral anticoagulants (DOACs) have been demonstrated to reduce the risk of venous and arterial thromboembolism in large randomized clinical trials of patients with VTE and AF, respectively, thus providing an attractive oral dosing option that does not require routine laboratory monitoring. In this review, we summarize available clinical trial data and guideline recommendations, and outline a practical approach to anticoagulation management of VTE and AF in cancer. 相似文献
186.
187.
Toshiro Hara Rony Chanoch-Myers Nathan D. Mathewson Chad Myskiw Lyla Atta Lillian Bussema Stephen W. Eichhorn Alissa C. Greenwald Gabriela S. Kinker Christopher Rodman L. Nicolas Gonzalez Castro Hiroaki Wakimoto Orit Rozenblatt-Rosen Xiaowei Zhuang Jean Fan Tony Hunter Inder M. Verma Kai W. Wucherpfennig Itay Tirosh 《Cancer cell》2021,39(6):779-792.e11
- Download : Download high-res image (228KB)
- Download : Download full-size image
188.
189.
Katherine M. Duszynski Nicole L. Pratt John W. Lynch Jesia G. Berry Michael S. Gold 《Vaccine》2019,37(2):280-288
Objective
To determine whether differences in combination DTaP vaccine types at 2, 4 and 6?months of age were associated with mortality (all-cause or non-specific), within 30?days of vaccination.Design
Observational nationwide cohort study.Setting
Linked population data from the Australian Childhood Immunisation Register and National Death Index.Participants
Australian infants administered a combination trivalent, quadrivalent or hexavalent DTaP vaccine (DTaP types) between January 1999 and December 2010 at 2, 4 and 6?months as part of the primary vaccination series. The study population included 2.9, 2.6, & 2.3?million children in the 2, 4 and 6?month vaccine cohorts, respectively.Main outcome measures
Infants were evaluated for the primary outcome of all-cause mortality within 30?days. A secondary outcome was non-specific mortality (unknown cause of death) within 30?days of vaccination. Non-specific mortality was defined as underlying or other cause of death codes, R95 ‘Sudden infant death syndrome’, R96 ‘Other sudden death, cause unknown’, R98 ‘Unattended death’, R99 ‘Other ill-defined and unspecified cause of mortality’ or where no cause of death was recorded.Results
The rate of 30?day all-cause mortality was low and declined from 127.4 to 59.3 deaths per 100,000 person-years between 2 and 6?month cohorts. When compared with trivalent DTaP vaccines, no elevated risk in all-cause or non-specific mortality was seen with any quadrivalent or hexavalent DTaP vaccines, for any cohort.Conclusion
Use of routine DTaP combination vaccines with differing disease antigens administered during the first six months of life is not associated with infant mortality. 相似文献190.
Stress Testing Versus CT Angiography in Patients With Diabetes and Suspected Coronary Artery Disease
Abhinav Sharma Adrian Coles Nishant K. Sekaran Neha J. Pagidipati Michael T. Lu Daniel B. Mark Kerry L. Lee Hussein R. Al-Khalidi Udo Hoffmann Pamela S. Douglas 《Journal of the American College of Cardiology》2019,73(8):893-902