全文获取类型
收费全文 | 4283197篇 |
免费 | 333793篇 |
国内免费 | 14037篇 |
专业分类
耳鼻咽喉 | 59421篇 |
儿科学 | 136476篇 |
妇产科学 | 111462篇 |
基础医学 | 659377篇 |
口腔科学 | 114830篇 |
临床医学 | 390153篇 |
内科学 | 772439篇 |
皮肤病学 | 107093篇 |
神经病学 | 356770篇 |
特种医学 | 165879篇 |
外国民族医学 | 507篇 |
外科学 | 655025篇 |
综合类 | 120022篇 |
现状与发展 | 23篇 |
一般理论 | 2640篇 |
预防医学 | 358848篇 |
眼科学 | 99844篇 |
药学 | 298997篇 |
27篇 | |
中国医学 | 11370篇 |
肿瘤学 | 209824篇 |
出版年
2021年 | 56641篇 |
2020年 | 36061篇 |
2019年 | 59166篇 |
2018年 | 74738篇 |
2017年 | 57148篇 |
2016年 | 63365篇 |
2015年 | 76377篇 |
2014年 | 110936篇 |
2013年 | 176542篇 |
2012年 | 125690篇 |
2011年 | 131626篇 |
2010年 | 127285篇 |
2009年 | 128286篇 |
2008年 | 117398篇 |
2007年 | 125317篇 |
2006年 | 133591篇 |
2005年 | 128644篇 |
2004年 | 128662篇 |
2003年 | 118676篇 |
2002年 | 107911篇 |
2001年 | 150519篇 |
2000年 | 145405篇 |
1999年 | 135052篇 |
1998年 | 70552篇 |
1997年 | 66583篇 |
1996年 | 64696篇 |
1995年 | 59976篇 |
1994年 | 54004篇 |
1993年 | 50242篇 |
1992年 | 96599篇 |
1991年 | 93206篇 |
1990年 | 89554篇 |
1989年 | 87278篇 |
1988年 | 80458篇 |
1987年 | 78916篇 |
1986年 | 74286篇 |
1985年 | 73400篇 |
1984年 | 61975篇 |
1983年 | 55671篇 |
1982年 | 46173篇 |
1981年 | 43250篇 |
1980年 | 40618篇 |
1979年 | 53378篇 |
1978年 | 44202篇 |
1977年 | 39032篇 |
1976年 | 36398篇 |
1975年 | 36417篇 |
1974年 | 39594篇 |
1973年 | 37817篇 |
1972年 | 35414篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
111.
112.
113.
Context Withania somnifera (L.) Dunal is traditionally used for treating various ailments, but lacks scientific evaluation.Objective This study evaluates Withania somnifera (WS) for its effect on platelet activity and inflammatory enzymes.Materials and methods Aqueous and ethanolic (1:1) leaf extracts were subjected to in vitro indirect haemolytic activity using Naja naja venom, human platelet aggregation was quantified for lipid peroxidation using arachidonic acid (AA) as agonist and 5-lipoxygenase (5-LOX) levels were determined using standard spectrometric assays. Further, molecular docking was performed by the ligand fit method using molegro software package (Molegro ApS, Aarhus, Denmark).Results The study found that aqueous and ethanol extracts have very negligible effect (15%) with an IC50 value of 13.8?mg/mL on PLA2 from Naja naja venom. Further, extracts of WS also had very little effect (18%) with an IC50 value of 16.6?mg/mL on malondialdehyde (MDA) formation. However, a 65% inhibition of 5-LOX with an IC50 value of 0.92?mg/mL was observed in 1:1 ethanol extracts. The same was evident from SAR model with the active ingredient withaferin A binding predominantly on Phe 77, Tyr 98, Arg 99, Asp 164, Leu 168, Ser 382, Arg 395, Tyr 396 and Tyr 614 with an atomic contact energy value of??128.96 compared to standard phenidone (?103.61). Thus, the current study validates the application of WS for inflammatory diseases.Conclusion This study reveals the inhibitory potential of W. somnifera on inflammatory enzymes and platelet aggregation. Thus, WS can serve as a newer, safer and affordable medicine for inflammatory diseases. 相似文献
114.
115.
116.
Gui-Qi Zhu Ke-Qing Shi Sha Huang Gui-Qian Huang Yi-Qian Lin Zhi-Rui Zhou Martin Braddock Yong-Ping Chen Ming-Hua Zheng 《Medicine》2015,94(11)
Major ursodeoxycholic acid (UDCA)-based therapies for primary biliary cirrhosis (PBC) include UDCA only, or combined with either methotrexate (MTX), corticosteroids (COT), colchicine (COC), or bezafibrate (BEF). As the optimum treatment regimen is unclear and warrants exploration, we aimed to compare these therapies in terms of patient mortality or liver transplantation (MOLT) and adverse events (AE).PubMed, the Cochrane Library, and Scopus were searched for randomized controlled trials up to August 31, 2014. We estimated the hazard ratios (HRs) for MOLT and odds ratios (ORs) for AE. A sensitivity analysis based on the dose of UDCA was also executed.Thirty-one eligible articles were included. Compared with COT plus UDCA, UDCA (HR 0.38, 95% confidence interval [CI] 0.09–1.39), BEF plus UDCA (HR 0.29, 95% CI 0.02–4.83), COC plus UDCA (HR 0.39, 95% CI 0.07–2.25), MTX plus UDCA (HR 0.28, 95% CI 0.05–1.63), or OBS (HR 0.49, 95% CI 0.11–2.01) all provided an increased risk of MOLT. With respect to drug AE profile, although not differing appreciably, BEF plus UDCA was associated with more AEs compared with UDCA (OR 3.16, 95% CI 0.59–20.67), COT plus UDCA (OR 2.27, 95% CI 0.15–33.36), COC plus UDCA (OR 1.00, 95% CI 0.09–12.16), MTX plus UDCA (OR 2.03, 95% CI 0.23–17.82), or OBS (OR 3.00, 95% CI 0.53–20.75). The results of sensitivity analyses were highly consistent with previous analyses.COT plus UDCA was the optimal UDCA-based regimen for both MOLT and AEs. BEF plus UDCA was most likely to cause AEs, whereas monotherapy with UDCA and coadministriation of COT plus UDCA appeared to be associated with the fewest AEs for PBC treatment. 相似文献
117.
118.
Feasibility and Diagnostic Potential of Pulmonary Transit Time Measurement by Contrast Echocardiography: A Pilot Study 下载免费PDF全文
119.
Harit Kapoor Kush Raj Lohani Tommy H. Lee Devendra K. Agrawal Sumeet K. Mittal 《CTS Clinical and Translational Science》2015,8(6):841-847
Esophageal adenocarcinoma is the fastest rising cancer in the United States. It develops from long‐standing gastroesophageal reflux disease which affects >20% of the general population. It carries a very poor prognosis with 5‐year survival <20%. The disease is known to sequentially progress from reflux esophagitis to a metaplastic precursor, Barrett''s esophagus and then onto dysplasia and esophageal adenocarcinoma. However, only few patients with reflux develop Barrett''s esophagus and only a minority of these turn malignant. The reason for this heterogeneity in clinical progression is unknown. To improve patient management, molecular changes which facilitate disease progression must be identified. Animal models can provide a comprehensive functional and anatomic platform for such a study. Rats and mice have been the most widely studied but disease homology with humans has been questioned. No animal model naturally simulates the inflammation to adenocarcinoma progression as in humans, with all models requiring surgical bypass or destruction of existing antireflux mechanisms. Valuable properties of individual models could be utilized to holistically evaluate disease progression. In this review paper, we critically examined the current animal models of Barrett''s esophagus, their differences and homologies with human disease and how they have shaped our current understanding of Barrett''s carcinogenesis. 相似文献
120.
Marta Rozanski Valentin Neuhaus Emily Thornton Stéphanie J. E. Becker James P. Rathmell David Ring 《Journal of hand and microsurgery》2015,7(1):30-35
This study used the National Survey of Ambulatory Surgery (NSAS) database to measure the incidence of and risk factors for symptoms in the ambulatory surgery center and problems within 24 h after isolated carpal tunnel release (CTR). The NSAS contained records on 400,000 adult patients with carpal tunnel syndrome who were treated with CTR in 2006, based on ICD-9 codes. The type of anesthesia used and factors associated with symptoms and problems were sought in bivariate and multivariable statistical analyses. The mean duration of the procedure was 16 ± 8.8 min. Only 5 % were performed under local anesthesia without sedation, 45 % with IV sedation, 28 % regional anesthesia, and 19 % general anesthesia. Symptoms in the ambulatory surgery center or a problem within 24 h after discharge were recorded in 10 % of patients, all of them minor and transient, including difficulties with pain and its treatment. The strongest risk factors were male sex, age of 45 years and older, and participation of an anesthesiologist. Local anesthesia and regional anesthesia were associated with more perioperative symptoms and postoperative problems. Most CTR are performed with some sedation in the United States. CTR is a safe procedure: one in 10 patients will experience a minor issue in the perioperative or immediate postoperative period. 相似文献