全文获取类型
收费全文 | 178183篇 |
免费 | 14042篇 |
国内免费 | 5433篇 |
专业分类
耳鼻咽喉 | 1189篇 |
儿科学 | 4057篇 |
妇产科学 | 4085篇 |
基础医学 | 26244篇 |
口腔科学 | 3206篇 |
临床医学 | 16999篇 |
内科学 | 23861篇 |
皮肤病学 | 1745篇 |
神经病学 | 10564篇 |
特种医学 | 3506篇 |
外国民族医学 | 25篇 |
外科学 | 15388篇 |
综合类 | 27212篇 |
现状与发展 | 15篇 |
一般理论 | 26篇 |
预防医学 | 11942篇 |
眼科学 | 4394篇 |
药学 | 18921篇 |
28篇 | |
中国医学 | 8925篇 |
肿瘤学 | 15326篇 |
出版年
2024年 | 277篇 |
2023年 | 2022篇 |
2022年 | 3766篇 |
2021年 | 6245篇 |
2020年 | 5424篇 |
2019年 | 5620篇 |
2018年 | 5483篇 |
2017年 | 5531篇 |
2016年 | 5603篇 |
2015年 | 5660篇 |
2014年 | 8984篇 |
2013年 | 10505篇 |
2012年 | 8437篇 |
2011年 | 9885篇 |
2010年 | 8575篇 |
2009年 | 8356篇 |
2008年 | 8468篇 |
2007年 | 9525篇 |
2006年 | 8842篇 |
2005年 | 8689篇 |
2004年 | 7578篇 |
2003年 | 6820篇 |
2002年 | 5106篇 |
2001年 | 4997篇 |
2000年 | 4162篇 |
1999年 | 3774篇 |
1998年 | 2753篇 |
1997年 | 2490篇 |
1996年 | 2601篇 |
1995年 | 2442篇 |
1994年 | 2189篇 |
1993年 | 1961篇 |
1992年 | 1762篇 |
1991年 | 1556篇 |
1990年 | 1369篇 |
1989年 | 1253篇 |
1988年 | 1134篇 |
1987年 | 891篇 |
1986年 | 732篇 |
1985年 | 878篇 |
1984年 | 870篇 |
1983年 | 550篇 |
1982年 | 682篇 |
1981年 | 569篇 |
1980年 | 493篇 |
1979年 | 421篇 |
1978年 | 349篇 |
1977年 | 280篇 |
1976年 | 301篇 |
1975年 | 195篇 |
排序方式: 共有10000条查询结果,搜索用时 203 毫秒
61.
目的:建立大黄特征化学成分和抗氧化活性相关联的二维指纹图谱,研究大黄抗氧化活性物质。方法:利用高效液相多检测器联用的抗氧化活性成分在线检测体系,对大黄中化学成分进行检测,共鉴定出大黄中化学成分15种;其中8种具有抗氧化活性;然后采用清除效率为指标对各活性成分的抗氧化活性进行评价。结果:结果发现化合物葡萄糖紫丁香酸、腺嘌呤、没食子酸、儿茶素或表儿茶素、双花母草素、2-O-桂皮酰-没食子酰葡萄糖等具有较强的清除ABTS·+的活性,而蒽醌类成分对ABTS·+的清除作用较弱。结论:采用HPLC-ABTS-DAD-Q-TOF/MS对大黄中的抗氧化活性成分进行快速分析鉴定,初步阐明大黄在抗氧化环节起作用的效应物质。 相似文献
62.
Could non-HDL-cholesterol be a better marker of atherogenic dyslipidemia in obstructive sleep apnea?
《Sleep medicine》2021
Background/objectiveObstructive sleep apnea (OSA) is independently associated with dyslipidemia, a surrogate marker of atherosclerosis. Low-density lipoprotein (LDL)-cholesterol is accepted as a major independent risk factor for cardiovascular disease. However, non-high-density lipoprotein (HDL)-cholesterol is a better marker of atherogenic dyslipidemia and recommended as a target of lipid lowering therapy. We aimed to assess the prevalence of atherogenic dyslipidemia, and relationship between OSA severity and serum LDL-cholesterol and non-HDL cholesterol levels in OSA patients.MethodsWe retrospectively evaluated treatment naïve 2361 subjects admitted to the sleep laboratory of a university hospital for polysomnography. All subjects’ lipid profile including total cholesterol, LDL-cholesterol, HDL-cholesterol, triglycerides, and non-HDL-cholesterol were measured.ResultsOut of 2361 patients (mean age 49.6 ± 11.9 years; 68.9% male, apnea-hypopnea index 36.6 ± 28.4/h), 185 (7.8%) had no OSA and 2176 (92.2%) had OSA. Atherogenic dyslipidemia prevalence was high (57–66%) in OSA patients, and especially increased in severe OSA compared to other groups (p < 0.05). Though total and LDL-cholesterol did not differ between those with and without OSA, non-HDL-cholesterol (p = 0.020), and triglycerides (p = 0.001) were higher and HDL-cholesterol levels (p = 0.018) were lower in OSA patients than non-OSA. Non-HDL-cholesterol was significantly correlated with OSA severity (p < 0.001) and hypoxia parameters (p < 0.01), whereas LDL-cholesterol showed no correlation.ConclusionsAtherogenic dyslipidemia is highly prevalent and non-HDL-cholesterol levels are significantly increased, predominantly in severe OSA patients. Non-HDL-cholesterol but not LDL-cholesterol, is significantly correlated with OSA severity and hypoxia parameters. Therefore, it could be better to use non-HDL-cholesterol, which is a guideline recommended target of lipid therapy, as a marker of atherosclerotic cardiovascular risk in OSA patients. 相似文献
63.
64.
《Saudi Pharmaceutical Journal》2022,30(6):669-678
BackgroundIschemia reperfusion (I/R) play an imperative role in the expansion of cardiovascular disease. Sinomenine (SM) has been exhibited to possess antioxidant, anticancer, anti-inflammatory, antiviral and anticarcinogenic properties. The aim of the study was scrutinized the cardioprotective effect of SM against I/R injury in rat.MethodsRat were randomly divided into normal control (NC), I/R control and I/R + SM (5, 10 and 20 mg/kg), respectively. Ventricular arrhythmias, body weight and heart weight were estimated. Antioxidant, inflammatory cytokines, inflammatory mediators and plasmin system indicator were accessed.ResultsPre-treated SM group rats exhibited the reduction in the duration and incidence of ventricular fibrillation, ventricular ectopic beat (VEB) and ventricular tachycardia along with suppression of arrhythmia score during the ischemia (30 and 120 min). SM treated rats significantly (P < 0.001) altered the level of antioxidant parameters. SM treatment significantly (P < 0.001) repressed the level of creatine kinase MB (CK-MB), creatine kinase (CK) and troponin I (Tnl). SM treated rats significantly (P < 0.001) repressed the tissue factor (TF), thromboxane B2 (TXB2), plasminogen activator inhibitor 1 (PAI-1) and plasma fibrinogen (Fbg) and inflammatory cytokines and inflammatory mediators.ConclusionOur result clearly indicated that SM plays anti-arrhythmia effect in I/R injury in the rats via alteration of oxidative stress and inflammatory reaction. 相似文献
65.
Marta López-Fauqued Laura Campora Frédérique Delannois Mohamed El Idrissi Lidia Oostvogels Ferdinandus J. De Looze Javier Diez-Domingo Thomas C. Heineman Himal Lal Janet E. McElhaney Shelly A. McNeil Wilfred Yeo Fernanda Tavares-Da-Silva 《Vaccine》2019,37(18):2482-2493
Background
The ZOE-50 (NCT01165177) and ZOE-70 (NCT01165229) phase 3 clinical trials showed that the adjuvanted recombinant zoster vaccine (RZV) was ≥90% efficacious in preventing herpes zoster in adults. Here we present a comprehensive overview of the safety data from these studies.Methods
Adults aged ≥50 (ZOE-50) and ≥70 (ZOE-70) years were randomly vaccinated with RZV or placebo. Safety analyses were performed on the pooled total vaccinated cohort, consisting of participants receiving at least one dose of RZV or placebo. Solicited and unsolicited adverse events (AEs) were collected for 7 and 30?days after each vaccination, respectively. Serious AEs (SAEs) were collected from the first vaccination until 12?months post-last dose. Fatal AEs, vaccination-related SAEs, and potential immune-mediated diseases (pIMDs) were collected during the entire study period.Results
Safety was evaluated in 14,645 RZV and 14,660 placebo recipients. More RZV than placebo recipients reported unsolicited AEs (50.5% versus 32.0%); the difference was driven by transient injection site and solicited systemic reactions that were generally seen in the first week post-vaccination. The occurrence of overall SAEs (RZV: 10.1%; Placebo: 10.4%), fatal AEs (RZV: 4.3%; Placebo: 4.6%), and pIMDs (RZV: 1.2%; Placebo: 1.4%) was balanced between groups. The occurrence of possible exacerbations of pIMDs was rare and similar between groups. Overall, except for the expected local and systemic symptoms, the safety results were comparable between the RZV and Placebo groups irrespective of participant age, gender, or race.Conclusions
No safety concerns arose, supporting the favorable benefit-risk profile of RZV. 相似文献66.
目的探讨喉癌患者血小板表面血小板膜糖蛋白Ⅱb/Ⅲa纤维蛋白原受体(PAC-1)、血小板P-选择素(CD62P)阳性表达率以及与患者临床病理特征和复发的关系。方法选取2014年1月~2015年12月间在我院耳鼻喉科手术治疗的116例喉癌患者,随访≥2年,并选取同期在我院体检的健康人群60例为对照组,采用流式细胞仪检测法检测外周血PAC-1和CD62P阳性率,并分析与临床病理特征、复发的关系。结果喉癌患者PAC-1和CD62P阳性表达率分别为(17.82±1.76)%和(22.87±3.13)%,明显高于健康人群(P<0.05);而且在喉癌患者PAC-1表达和CD62P表达呈正相关性(r=0.238,P<0.05)。T3-T4分期或N2-N3分期患者PAC-1和CD62P阳性表达率高于T1-T2分期或N0-N1分期患者(P<0.05)。另外远处转移组PAC-1和CD62P阳性表达率高于未发生转移组(P<0.05);随访期间有24例患者复发,复发率为20.69%。复发喉癌患者PAC-1、CD62P阳性表达率分别为(17.02±0.85)%和(21.84±1.17)%,明显高于未复发的喉癌患者(P<0.05)。经Logistics回归分析,PAC-1和CD62P是喉癌患者复发的独立危险因素(P<0.05)。结论PAC-1和CD62P阳性表达率与喉癌患者T分期、淋巴结转移和远处转移密切相关,同时可作为喉癌局部复发、区域淋巴结转移、远处转移的预测指标。 相似文献
67.
Walid K. Abu Saleh Phillip Mason Odeaa Al Jabbari Hany Samir Brian A. Bruckner 《Texas Heart Institute journal / from the Texas Heart Institute of St. Luke's Episcopal Hospital, Texas Children's Hospital》2015,42(6):569-571
The Impella 5.0, a percutaneously inserted left ventricular assist device, has been used to support patients who have severe heart failure or who are undergoing high-risk percutaneous coronary intervention. We report our surgical placement of the Impella 5.0, through a graft sewn to the aorta, to unload the left ventricle of a 59-year-old man who was undergoing venoarterial extracorporeal membrane oxygenation for postcardiotomy shock. The patient underwent successful placement of a long-term left ventricular assist device before his discharge from the hospital. The versatility of the Impella 5.0 is exemplified in this patient who was successfully bridged to long-term support. 相似文献
68.
69.
《Arab Journal Of Gastroenterology》2021,22(3):229-235
Background and Study AimsIn developing countries, endemic indications, blood shortages, and the scarcity of liver surgeons and intensive care providers can affect liver resection (LR) outcomes, but these have been rarely addressed in the literature. Therefore, in this study we determined risk factors for major complications after LR in a North African general surgery and teaching department.Patients and MethodsFrom January 2010 to December 2015, 213 consecutive LRs were performed on 203 patients. All patients underwent a postoperative follow-up of >90 days. Postoperative complications were assessed according to the Clavien–Dindo (CD) classification of surgical complications. A score of CD ≥III is considered as major postoperative complications. In this study, we analyzed the variables assumed to affect these complications.ResultsThe overall 90-day complication rate was 35.7% (n = 76), including a CD ≥III of 14% (n = 30) and a mortality rate of 6.1% (n = 14). According to the multivariate analysis, a preoperative performance status (PS) of ≥2 (P = 0.011; odds ratios [OR], 6.8; 95% confidence intervals [CI], 1.55–29.8), an estimated intraoperative blood loss of >500 ml (P = 0.002; OR, 3.71; 95% CI, 1.23–11.20), and bilioenteric anastomosis (P < 0.004; OR, 7.76; 95% CI, 1.5–3.89) were independent risk factors for major complications after LR.ConclusionWe recommend that, in the setting of a non-Eastern/non-Western general surgery and teaching department, patients with a PS of ≥2 should undergo a specific selection and preoperative optimization protocol; intermittent clamping indications should be extended; and special attention should paid to patients undergoing LR associated with biliary reconstruction, such as for perihilar cholangiocarcinoma. 相似文献
70.