收费全文 | 46376篇 |
免费 | 2990篇 |
国内免费 | 117篇 |
耳鼻咽喉 | 598篇 |
儿科学 | 1247篇 |
妇产科学 | 787篇 |
基础医学 | 6739篇 |
口腔科学 | 807篇 |
临床医学 | 4241篇 |
内科学 | 10164篇 |
皮肤病学 | 1042篇 |
神经病学 | 4262篇 |
特种医学 | 1740篇 |
外国民族医学 | 15篇 |
外科学 | 6760篇 |
综合类 | 450篇 |
一般理论 | 34篇 |
预防医学 | 3445篇 |
眼科学 | 1222篇 |
药学 | 2956篇 |
1篇 | |
中国医学 | 95篇 |
肿瘤学 | 2878篇 |
2022年 | 240篇 |
2021年 | 632篇 |
2020年 | 408篇 |
2019年 | 610篇 |
2018年 | 720篇 |
2017年 | 520篇 |
2016年 | 614篇 |
2015年 | 737篇 |
2014年 | 1028篇 |
2013年 | 1543篇 |
2012年 | 2252篇 |
2011年 | 2403篇 |
2010年 | 1441篇 |
2009年 | 1433篇 |
2008年 | 2277篇 |
2007年 | 2509篇 |
2006年 | 2447篇 |
2005年 | 2540篇 |
2004年 | 2362篇 |
2003年 | 2207篇 |
2002年 | 2234篇 |
2001年 | 1095篇 |
2000年 | 1045篇 |
1999年 | 1008篇 |
1998年 | 625篇 |
1997年 | 571篇 |
1996年 | 490篇 |
1995年 | 443篇 |
1994年 | 406篇 |
1993年 | 360篇 |
1992年 | 719篇 |
1991年 | 721篇 |
1990年 | 676篇 |
1989年 | 614篇 |
1988年 | 602篇 |
1987年 | 552篇 |
1986年 | 570篇 |
1985年 | 519篇 |
1984年 | 447篇 |
1983年 | 379篇 |
1982年 | 357篇 |
1981年 | 356篇 |
1980年 | 313篇 |
1979年 | 360篇 |
1978年 | 298篇 |
1977年 | 301篇 |
1976年 | 261篇 |
1975年 | 264篇 |
1974年 | 278篇 |
1973年 | 239篇 |
Methods: Prospective cross-sectional study.
Results: Twenty-seven of 106 patients had positive PCR and/or GWC results on aqueous humor (AH) sampling and 15 of 27 (55.6%) were HIV-positive. Patients with non-anterior uveitis (NAU) were more likely to be HIV+ (p = 0.005). More than 1 possible pathogen was identified in 9 of 27 patients of whom 7 were HIV+. The final clinical diagnosis was discordant with AH findings in 9 of 27 cases. A positive EBV PCR result was associated with a discordant diagnosis (p = 0.001). All cases of herpetic anterior uveitis (42.9% HIV+) tested PCR-/GWC+ while all cases of herpetic NAU tested PCR+/GWC- (83.3% HIV+). All rubella virus cases were PCR+/GWC+.
Conclusion: PCR is useful to diagnose herpetic NAU in HIV+ patients while GWC is useful to diagnose herpetic anterior uveitis. 相似文献
Objective
Comparative survival between neoadjuvant chemotherapy and adjuvant chemotherapy for patients with cT2-4N0-1M0 non–small cell lung cancer has not been extensively studied.Methods
Patients with cT2-4N0-1M0 non–small cell lung cancer who received platinum-based chemotherapy were retrospectively identified. Exclusion criteria included stage IV disease, induction radiotherapy, and targeted therapy. The primary end point was disease-free survival. Secondary end points were overall survival, chemotherapy tolerance, and ability of Response Evaluation Criteria In Solid Tumors response to predict survival. Survival was estimated using the Kaplan–Meier method, compared using the log-rank test and Cox proportional hazards models, and stratified using matched pairs after propensity score matching.Results
In total, 330 patients met the inclusion criteria (n = 92/group after propensity-score matching; median follow-up, 42 months). Five-year disease-free survival was 49% (95% confidence interval, 39-61) for neoadjuvant chemotherapy versus 48% (95% confidence interval, 38-61) for adjuvant chemotherapy (P = .70). On multivariable analysis, disease-free survival was not associated with neoadjuvant chemotherapy or adjuvant chemotherapy (hazard ratio, 1.1; 95% confidence interval, 0.64-1.90; P = .737), nor was overall survival (hazard ratio, 1.21; 95% confidence interval, 0.63-2.30; P = .572). The neoadjuvant chemotherapy group was more likely to receive full doses and cycles of chemotherapy (P = .014/0.005) and had fewer grade 3 or greater toxicities (P = .001). Response Evaluation Criteria In Solid Tumors response to neoadjuvant chemotherapy was associated with disease-free survival (P = .035); 15% of patients receiving neoadjuvant chemotherapy (14/92) had a major pathologic response.Conclusions
Timing of chemotherapy, before or after surgery, is not associated with an improvement in overall or disease-free survival among patients with cT2-4N0-1M0 non–small cell lung cancer who undergo complete surgical resection. 相似文献![点击此处可从《Acta paediatrica (Oslo, Norway : 1992)》网站下载免费的PDF全文](/ch/ext_images/free.gif)
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Areas covered: This article covers the pharmacokinetics and pharmacodynamics of vilazodone and provides an evaluation of the clinical usefulness of vilazodone for the treatment of MDD and anxiety disorders. A literature search was performed using PubMed/MEDLINE, Web of Science and the Cochrane Library.
Expert opinion: Studies have shown that vilazodone is significantly superior to placebo. However, vilazodone cannot as yet be recommended as a first-line treatment option for MDD as it is unclear whether the drug’s dual mechanism of action provides greater efficacy than prevailing treatment options. Moreover, more phase IV studies are needed to establish its efficacy and long-term safety in larger and more diverse populations. Although vilazodone may have an additional advantage for the treatment of anxiety symptoms in MDD, here also additional studies are required to confirm its efficacy over and above SSRI alternatives and other antidepressant treatments. Therefore, presently, vilazodone should be considered as a second- or third-line treatment option for MDD and GAD. 相似文献