全文获取类型
收费全文 | 22328篇 |
免费 | 1592篇 |
国内免费 | 1159篇 |
专业分类
耳鼻咽喉 | 28篇 |
儿科学 | 412篇 |
妇产科学 | 174篇 |
基础医学 | 1541篇 |
口腔科学 | 32篇 |
临床医学 | 2744篇 |
内科学 | 6291篇 |
皮肤病学 | 51篇 |
神经病学 | 647篇 |
特种医学 | 2367篇 |
外国民族医学 | 5篇 |
外科学 | 3303篇 |
综合类 | 3283篇 |
预防医学 | 622篇 |
眼科学 | 78篇 |
药学 | 1817篇 |
9篇 | |
中国医学 | 523篇 |
肿瘤学 | 1152篇 |
出版年
2024年 | 15篇 |
2023年 | 322篇 |
2022年 | 518篇 |
2021年 | 818篇 |
2020年 | 804篇 |
2019年 | 757篇 |
2018年 | 768篇 |
2017年 | 717篇 |
2016年 | 734篇 |
2015年 | 856篇 |
2014年 | 1407篇 |
2013年 | 1516篇 |
2012年 | 1247篇 |
2011年 | 1432篇 |
2010年 | 1177篇 |
2009年 | 1253篇 |
2008年 | 1173篇 |
2007年 | 1299篇 |
2006年 | 1105篇 |
2005年 | 1006篇 |
2004年 | 742篇 |
2003年 | 643篇 |
2002年 | 556篇 |
2001年 | 566篇 |
2000年 | 407篇 |
1999年 | 388篇 |
1998年 | 330篇 |
1997年 | 257篇 |
1996年 | 251篇 |
1995年 | 269篇 |
1994年 | 266篇 |
1993年 | 184篇 |
1992年 | 151篇 |
1991年 | 127篇 |
1990年 | 113篇 |
1989年 | 110篇 |
1988年 | 87篇 |
1987年 | 70篇 |
1986年 | 79篇 |
1985年 | 86篇 |
1984年 | 78篇 |
1983年 | 41篇 |
1982年 | 66篇 |
1981年 | 60篇 |
1980年 | 53篇 |
1979年 | 30篇 |
1978年 | 36篇 |
1977年 | 28篇 |
1976年 | 26篇 |
1974年 | 15篇 |
排序方式: 共有10000条查询结果,搜索用时 531 毫秒
1.
2.
3.
4.
5.
Zongzhang Huang Qigu Yao Jianping Zhu Ying He Yanghao Chen Feng Wu Teng Hua 《Diagnostic and interventional imaging》2021,102(5):279-285
PurposeThe purpose of this study was to make a systematic review and meta-analysis to determine the stent diameter (8 mm vs. 10 mm) that conveys better safety and clinical efficacy for transjugular intrahepatic portosystemic shunt (TIPS).Materials and methodsFour databases were used to identify clinical trials published from inception until March 2020. Data were extracted to estimate and compare one-year and three-year overall survivals, hepatic encephalopathy, variceal rebleeding, and shunt dysfunction rates between patients with 8 mm covered stents and those with 10 mm covered stents.ResultsFive eligible studies were selected, which included 489 patients (316 men, 173 women). The 8 mm covered stent group had higher efficacy regarding one-year or three-year overall survival (odds ratio [OR], 2.88; P = 0.003) and (OR, 1.81; P = 0.04) and lower hepatic encephalopathy (OR, 0.69; P = 0.04) compared with 10 mm covered stent group. There were no significant differences in variceal rebleeding rate (OR 0.80; P = 0.67). However, shunt dysfunction was lower in 10 mm covered stent group (OR, 2.26; P = 0.003).ConclusionsOur results suggest that the use of 8 mm covered stents should be preferred to that of 10 mm covered stents for TIPS placement when portal pressure is frequently monitored. 相似文献
6.
Qing-Yang Que Lin-Cheng Zhang Jia-Qi Bao Sun-Bin Ling Xiao Xu 《World journal of gastrointestinal surgery》2022,14(5):397-408
Over the last 40 years, the incidence and prevalence of gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs) have continued to increase. Compared to other epithelial neoplasms in the same organ, GEP-NENs exhibit indolent biological behavior, resulting in more chances to undergo surgery. However, the role of surgery in high-grade or advanced GEP-NENs is still controversial. Surgery is associated with survival improvement of well-differentiated high-grade GEP-NENs, whereas poorly differentiated GEP-NENs that may benefit from resection require careful selection based on Ki67 and other tissue bio markers. Additionally, surgery also plays an important role in locally advanced and metastatic disease. For locally advanced GEP-NENs, isolated major vascular involvement is no longer an absolute contraindication. In the setting of metastatic GEP-NENs, radical intended surgery is recommended for patients with low-grade and resectable metastases. For unresectable metastatic disease, a variety of surgical approaches, including cytoreduction of liver metastasis, liver transplantation, and surgery after neoadjuvant treatment, show survival benefits. Primary tumor resection in GEP-NENs with unresectable metastatic disease is associated with symptom control, prolonged survival, and improved sensitivity toward systemic therapies. Although there is no established neoadjuvant or adjuvant strategy, increasing attention has been given to this emerging research area. Some studies have reported that neoadjuvant therapy effectively reduces tumor burden, improves the effectiveness of subsequent surgery, and decreases surgical complications. 相似文献
7.
8.
《Journal of vascular and interventional radiology : JVIR》2020,31(7):1103-1109
PurposeTo explore the safety and effectiveness of bronchial artery (BA) embolization (BAE) in children with pulmonary hemorrhage.Materials and MethodsBetween February 2016 and February 2019, 41 patients (median age, 4 y; interquartile range, 2.3-8 y; median weight, 17.6 kg; interquartile range, 12.3–23.6 kg) underwent BAE. The indication of BAE included massive hemoptysis in 10 patients (24.4%), recurrent hemoptysis in 18 patients (43.9%), and refractory anemia in 13 patients (31.7%). The main etiology of pulmonary hemorrhage included pulmonary hemosiderosis (58.5%), congenital heart disease (17.1%), and infection (14.6%). A retrospective review was conducted of clinical outcomes of BAE.ResultsThere were 44 embolization sessions, with a total of 137 embolized vessels. Pulmonary hemorrhage was caused by BAs in 30 cases, nonbronchial systemic arteries plus BAs in 10, and nonbronchial systemic arteries in 1. Embolic particles were used in 30 cases (24 polyvinyl alcohol [PVA] and 6 microsphere), coils in 9 cases, and particles plus coils in 5 cases (4 PVA and 1 microsphere). Technical success (ability to embolize abnormal vessel) was achieved in 97.6% of patients (40 of 41), and clinical success (complete or partial resolution of hemoptysis within 30 days of embolization) was achieved in 90.2% (37 of 41). There was 1 procedure-related complication (2.4%) of cerebral infarction and 1 death from multiple-organ dysfunction (2.4%). Bleeding-free survival rates at 6, 12, 24, and 36 months were 92.5%, 83.9%, 83.9%, and 70.8%, respectively.ConclusionsBAE is a safe and effective procedure in children with pulmonary hemorrhage. 相似文献
9.
目的 探讨肝动脉化疗栓塞(transcatheter arterial chemoembolization,TACE)术前天冬氨酸氨基转移酶与淋巴细胞比值(aspartate aminotransferase to lymphocyte ratio index,ALRI)在原发性肝癌并门脉癌栓(primary liver cancer-portal vein tumor thrombosis,PLC-PVTT)患者预后预测中的价值。方法 选取2013年11月21日至2018年8月22日于广西医科大学附属肿瘤医院接受TACE治疗的175例PLC-PVTT患者为研究对象。采用时间依赖性ROC曲线确定ALRI的最佳临界值。采用Cox 回归模型分析总生存期(overall survival,OS)的独立预测因素,Kaplan-Meier法计算生存率。结果 ROC曲线显示,ALRI的最佳临界值为49.37,对应曲线下面积为0.71。Kaplan-Meier分析显示,ALRI>49.37的患者OS较ALRI≤49.37的患者短(P=0.003)。Cox 回归分析结果显示,ALRI>49.37、行1次以上TACE治疗、Child-Pugh分级B级、凝血酶原时间≥13 s是患者TACE术后OS的独立危险因素(均P<0.05)。结论 TACE术前ALRI>49.37是PLC-PVTT患者OS的独立危险因素。 相似文献
10.
《Drug metabolism and pharmacokinetics》2020,35(1):56-70
Hepatic uptake mediated by organic anion transporting polypeptide (OATP) 1B1 and 1B3 can serve as a major elimination pathway for various anionic drugs and as a site of drug-drug interactions (DDIs). This article provides an overview of the in vitro approaches used to predict human hepatic clearance (CLh) and the risk of DDIs involving OATP1Bs. On the basis of the so-called extended clearance concept, in vitro–in vivo extrapolation methods using human hepatocytes as in vitro systems have been used to predict the CLh involving OATP1B-mediated hepatic uptake. CLh can be quantitatively predicted using human donor lots possessing adequate OATP1B activities. The contribution of OATP1Bs to hepatic uptake can be estimated by the relative activity factor, the relative expression factor, or selective inhibitor approaches, which offer generally consistent outcomes. In OATP1B1 inhibition assays, substantial substrate dependency was observed. The time-dependent inhibition of OATP1B1 was also noted and may be a mechanism underlying the in vitro–in vivo differences in the inhibition constant of cyclosporine A. Although it is still challenging to quantitatively predict CLh and DDIs involving OATP1Bs from only preclinical data, understanding the utility and limitation of the current in vitro methods will pave the way for better prediction. 相似文献