全文获取类型
收费全文 | 136835篇 |
免费 | 12253篇 |
国内免费 | 8646篇 |
学科分类
医药卫生 | 157734篇 |
出版年
2024年 | 420篇 |
2023年 | 1857篇 |
2022年 | 4731篇 |
2021年 | 6479篇 |
2020年 | 4708篇 |
2019年 | 4087篇 |
2018年 | 4433篇 |
2017年 | 4083篇 |
2016年 | 4084篇 |
2015年 | 6412篇 |
2014年 | 7849篇 |
2013年 | 7370篇 |
2012年 | 10734篇 |
2011年 | 11622篇 |
2010年 | 7833篇 |
2009年 | 6588篇 |
2008年 | 8064篇 |
2007年 | 7779篇 |
2006年 | 7522篇 |
2005年 | 6877篇 |
2004年 | 5140篇 |
2003年 | 4986篇 |
2002年 | 4128篇 |
2001年 | 3100篇 |
2000年 | 2715篇 |
1999年 | 2592篇 |
1998年 | 1693篇 |
1997年 | 1546篇 |
1996年 | 1220篇 |
1995年 | 1197篇 |
1994年 | 1070篇 |
1993年 | 664篇 |
1992年 | 739篇 |
1991年 | 671篇 |
1990年 | 568篇 |
1989年 | 507篇 |
1988年 | 372篇 |
1987年 | 383篇 |
1986年 | 269篇 |
1985年 | 207篇 |
1984年 | 119篇 |
1983年 | 76篇 |
1982年 | 59篇 |
1981年 | 53篇 |
1980年 | 35篇 |
1979年 | 38篇 |
1978年 | 6篇 |
1975年 | 7篇 |
1973年 | 10篇 |
1972年 | 6篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Sophocarpine attenuates toll‐like receptor 4 in steatotic hepatocytes to suppress pro‐inflammatory cytokines synthesis 下载免费PDF全文
2.
3.
4.
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
5.
6.
Fluid is usually restricted during thoracic surgery, and vasoactive agents are often administered to maintain blood pressure. One-lung ventilation (OLV) decreases arterial oxygenation; thus oxygen delivery to the brain can be decreased. In this study, we compared phenylephrine and dopamine with respect to maintaining cerebral oxygenation during OLV in major thoracic surgery.Sixty-three patients undergoing lobectomies were randomly assigned to the dopamine (D) or phenylephrine (P) group. The patients’ mean arterial pressure was maintained within 20% of baseline by a continuous infusion of dopamine or phenylephrine. Maintenance fluid was kept at 5 mL/kg/h. The depth of anesthesia was maintained with desflurane 1MAC and remifentanil infusion under bispectral index guidance. Regional cerebral oxygen saturation (rScO2) and hemodynamic variables were recorded using near-infrared spectroscopy and esophageal cardiac Doppler.The rScO2 was higher in the D group than the P group during OLV (OLV 60 min: 71 ± 6% vs 63 ± 12%; P = 0.03). The number of patients whose rScO2 dropped more than 20% from baseline was 0 and 6 in the D and P groups, respectively (P = 0.02). The D group showed higher cardiac output, but lower mean arterial pressure than the P group (4.7 ± 1.0 vs 3.9 ± 1.2 L/min; 76.7 ± 8.1 vs 84.5 ± 7.5 mm Hg; P = 0.02, P = 0.02). Among the variables, age, hemoglobin concentration, and cardiac output were associated with rScO2 by correlation analysis.Dopamine was superior to phenylephrine in maintaining cerebral oxygenation during OLV in thoracic surgery. 相似文献
7.
8.
9.
Recent studies have reported an association between gastroesophageal reflux disease (GERD) and atrial fibrillation (AF). The objective of the present study was to evaluate whether AF is one of the risk factors for GERD occurrence.In this hospital-based, retrospective, case–control study, the patients were classified into 2 groups. The patients diagnosed with new AF were assigned to the AF group (n = 1612); those diagnosed without AF and GERD were assigned to the control group (n = 1612). The subjects in the control group were selected from outpatients of total healthcare center without a history of AF or GERD, and matched for age and gender. We evaluated the incidence of GERD and risk factors for GERD occurrence between the 2 groups.The number of patients experiencing occurrence of GERD during the follow-up period was significantly higher in the AF group than those in the control group, respectively (129 patients vs 98 subjects, P = 0.037). The incidence of GERD was significantly higher in the AF group than in the control group by Kaplan–Meier analysis with log-rank test (P = 0.008). The AF group''s adjusted hazard ratio of GERD occurrence against that of the control group was 1.37 (95% confidence interval [CI]: 1.16–1.57; P = 0.009) according to Cox''s proportional hazard model.The presence of AF appears to increase the incidence of GERD and may be considered a risk factor for the development of GERD. Further, large prospective and cohort studies will be required to better establish the correlation of GERD with AF. 相似文献
10.