全文获取类型
| 收费全文 | 42890篇 |
| 免费 | 2998篇 |
| 国内免费 | 151篇 |
专业分类
| 耳鼻咽喉 | 355篇 |
| 儿科学 | 1461篇 |
| 妇产科学 | 989篇 |
| 基础医学 | 4993篇 |
| 口腔科学 | 881篇 |
| 临床医学 | 4391篇 |
| 内科学 | 9180篇 |
| 皮肤病学 | 743篇 |
| 神经病学 | 4372篇 |
| 特种医学 | 1363篇 |
| 外科学 | 6491篇 |
| 综合类 | 663篇 |
| 一般理论 | 60篇 |
| 预防医学 | 3376篇 |
| 眼科学 | 1112篇 |
| 药学 | 2966篇 |
| 中国医学 | 45篇 |
| 肿瘤学 | 2598篇 |
出版年
| 2023年 | 150篇 |
| 2022年 | 245篇 |
| 2021年 | 721篇 |
| 2020年 | 450篇 |
| 2019年 | 709篇 |
| 2018年 | 859篇 |
| 2017年 | 670篇 |
| 2016年 | 688篇 |
| 2015年 | 881篇 |
| 2014年 | 1247篇 |
| 2013年 | 1864篇 |
| 2012年 | 2816篇 |
| 2011年 | 3048篇 |
| 2010年 | 1715篇 |
| 2009年 | 1595篇 |
| 2008年 | 2799篇 |
| 2007年 | 3009篇 |
| 2006年 | 2930篇 |
| 2005年 | 3003篇 |
| 2004年 | 2829篇 |
| 2003年 | 2609篇 |
| 2002年 | 2603篇 |
| 2001年 | 398篇 |
| 2000年 | 248篇 |
| 1999年 | 423篇 |
| 1998年 | 634篇 |
| 1997年 | 467篇 |
| 1996年 | 419篇 |
| 1995年 | 371篇 |
| 1994年 | 317篇 |
| 1993年 | 314篇 |
| 1992年 | 271篇 |
| 1991年 | 229篇 |
| 1990年 | 221篇 |
| 1989年 | 212篇 |
| 1988年 | 204篇 |
| 1987年 | 175篇 |
| 1986年 | 201篇 |
| 1985年 | 203篇 |
| 1984年 | 298篇 |
| 1983年 | 251篇 |
| 1982年 | 323篇 |
| 1981年 | 288篇 |
| 1980年 | 282篇 |
| 1979年 | 167篇 |
| 1978年 | 164篇 |
| 1977年 | 160篇 |
| 1976年 | 140篇 |
| 1975年 | 127篇 |
| 1974年 | 140篇 |
排序方式： 共有10000条查询结果，搜索用时 15 毫秒
1.
Elizabeth D. Krebs Robert B. Hawkins J. Hunter Mehaffey Clifford E. Fonner Alan M. Speir Mohammed A. Quader Jeffrey B. Rich Leora T. Yarboro Nicholas R. Teman Gorav Ailawadi 《The Journal of thoracic and cardiovascular surgery》2019,157(4):1533-1542.e2
Objectives
Expedient extubation after cardiac surgery has been associated with improved outcomes, leading to postoperative extubation frequently during overnight hours. However, recent evidence in a mixed medical-surgical intensive care unit population demonstrated worse outcomes with overnight extubation. This study investigated the impact of overnight extubation in a statewide, multicenter Society of Thoracic Surgeons database.Methods
Records from 39,812 patients undergoing coronary artery bypass grafting or valve operations (2008-2016) and extubated within 24 hours were stratified according to extubation time between 06:00 and 18:00 (day) or between 18:00 and 6:00 (overnight). Outcomes including reintubation, mortality, and composite morbidity-mortality were evaluated using hierarchical regression models adjusted for Society of Thoracic Surgeons predictive risk scores. To further analyze extubation during the night, a subanalysis stratified patients into 3 groups: 06:00 to 18:00, 18:00 to 24:00, and 24:00 to 06:00.Results
A total of 20,758 patients were extubated overnight (52.1%) and were slightly older (median age 66 vs 65 years, P < .001) with a longer duration of ventilation (4 vs 7 hours, P < .001). Day and overnight extubation were associated with equivalent operative mortality (1.7% vs 1.7%, P = .880), reintubation (3.7% vs 3.4%, P = .141), and composite morbidity-mortality (8.2% vs 8.0%, P = .314). After risk adjustment, overnight extubation was not associated with any difference in reintubation, mortality, or composite morbidity-mortality. On subanalysis, those extubated between 24:00 and 06:00 exhibited increased composite morbidity-mortality (odds ratio, 1.18; P = .001) but no difference in reintubation or mortality.Conclusions
Extubation overnight was not associated with increased mortality or reintubation. These results suggest that in the appropriate clinical setting, it is safe to routinely extubate cardiac surgery patients overnight. 相似文献2.
3.
4.
5.
Alan. B. Franklin Sarah N. Bevins Jeremy W. Ellis Ryan S. Miller Susan A. Shriner J. Jeffrey Root Daniel P. Walsh Thomas J. Deliberto 《Transboundary and Emerging Diseases》2019,66(2):705-714
Using data on waterfowl band recoveries, we identified spatially explicit hotspots of concentrated waterfowl movement to predict occurrence and spatial spread of a novel influenza A virus (clade 2.3.4.4) introduced from Asia by waterfowl from an initial outbreak in North America in November 2014. In response to the outbreak, the hotspots of waterfowl movement were used to help guide sampling for clade 2.3.4.4 viruses in waterfowl as an early warning for the US poultry industry during the outbreak . After surveillance sampling of waterfowl, we tested whether there was greater detection of clade 2.3.4.4 viruses inside hotspots. We found that hotspots defined using kernel density estimates of waterfowl band recoveries worked well in predicting areas with higher prevalence of the viruses in waterfowl. This approach exemplifies the value of ecological knowledge in predicting risk to agricultural security. 相似文献
6.
Srdan Verstovsek MD PhD Jean-Jacques Kiladjian MD PhD Alessandro M. Vannucchi MD Ruben A. Mesa MD FACP Peg Squier MD PhD J. E. Hamer-Maansson MSPH Claire Harrison MD 《Cancer》2023,129(11):1681-1690
Background
In a pooled analysis of the phase 3 Controlled Myelofibrosis Study With Oral JAK Inhibitor Treatment I (COMFORT-I) and COMFORT-II clinical trials, adult patients with intermediate-2 or high-risk myelofibrosis who received oral ruxolitinib at randomization or after crossover from placebo or best available therapy (BAT) had improved overall survival (OS).Methods
This post hoc analysis of pooled COMFORT data examined relevant disease outcomes based on the disease duration (≤12 or >12 months from diagnosis) before ruxolitinib initiation.Results
The analysis included 525 patients (ruxolitinib: ≤12 months, n = 84; >12 months, n = 216; placebo/BAT: ≤12 months, n = 66; >12 months, n = 159); the median age was 65.0–70.0 years. Fewer thrombocytopenia and anemia events were observed among patients who initiated ruxolitinib treatment earlier. At Weeks 24 and 48, the spleen volume response (SVR) was higher for patients who initiated ruxolitinib earlier (47.6% vs. 32.9% at Week 24, p = .0610; 44.0% vs. 26.9% at Week 48, p = .0149). In a multivariable analysis of factors associated with spleen volume reduction, a logistic regression model that controlled for confounding factors found that a significantly greater binary reduction was observed among patients with shorter versus longer disease duration (p = .022). At Week 240, OS was significantly improved among patients who initiated ruxolitinib earlier (63% [95% CI, 51%‒73%] vs. 57% [95% CI, 49%‒64%]; hazard ratio, 1.53; 95% CI, 1.01‒2.31; p = .0430). Regardless of disease duration, a longer OS was observed for patients who received ruxolitinib versus those who received placebo/BAT.Conclusions
These findings suggest that earlier ruxolitinib initiation for adult patients with intermediate-2 and high-risk myelofibrosis may improve clinical outcomes, including fewer cytopenia events, durable SVR, and prolonged OS.Plain Language Summary
- Patients with myelofibrosis, a bone marrow cancer, often do not live as long as the general population. These patients may also have an enlarged spleen and difficult symptoms such as fatigue.
- Two large clinical trials showed that patients treated with the drug ruxolitinib lived longer and had improved symptoms compared to those treated with placebo or other standard treatments.
- Here it was examined whether starting treatment with ruxolitinib earlier (i.e., within a year of diagnosis) provided benefits versus delaying treatment.
- Patients who received ruxolitinib within a year of diagnosis lived longer and experienced fewer disease symptoms than those whose treatment was delayed.
7.
8.
9.
Saisanjana Kalagara Adam E.M. Eltorai J. Mason DePasse Alan H. Daniels 《The spine journal》2019,19(1):182-185
BACKGROUND
Online physician rating websites are increasingly used by patients to evaluate their doctors. The purpose of this investigation was to evaluate factors associated with better spine surgeon ratings.METHODS
Orthopedic spine surgeons were randomly selected from the North American Spine Society directory utilizing a random number generator. Surgeon profiles on three physician rating websites, namely, www.HealthGrades.com, www.Vitals.com, and www.RateMDs.com, were analyzed to gather qualitative and quantitative data on patients’ perceptions of the surgeons. Independent variables from the websites were analyzed in relation to overall physician or patient satisfaction rating. Comments were coded by subject into following three categories: professional competence, bedside manner, and practice characteristics.RESULTS
A total of 250 surgeons were evaluated, and 92% (n=230) of these doctors had at least one rating among the three websites. The surgeons with a higher average rating had significantly better trust (p<.01), scheduling (p<.01), staff (p<.01), helpfulness (p<.01), and punctuality (p<.01) scores but significantly less experience (p<.05). A linear regression model for the average rating of each surgeon (R2 value=0.754) yielded only following three significant variables: trustworthiness (p<.01), experience match (p<.05), and the average number of negative comments on surgeon's professional competence (p<.05). Trustworthiness (β=0.749) was the strongest predictor variable of physician rating, followed by the number of negative professional competence comments (β=?0.132) and experience match (β=?0.112).CONCLUSIONS
This investigation assessed spine surgeon online patient ratings and categorized factors that patients associate with quality care. Trustworthiness was the most significant predictor of positive ratings, whereas ease of scheduling, quality of staff, helpfulness, and punctuality were also associated with higher patient ratings. Understanding what patients value may help optimize care of spine surgery patients. 相似文献10.
Hanna Lee Mary K. Tan Andrew T. Yan Paul Angaran Paul Dorian Claudia Bucci Jean C. Gregoire Alan D. Bell Martin S. Green Peter L. Gross Allan Skanes Charles R. Kerr L. Brent Mitchell Jafna L. Cox Vidal Essebag Brett Heilbron Krishnan Ramanathan Carl Fournier Shaun G. Goodman 《The Canadian journal of cardiology》2019,35(2):160-168