首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   23559篇
  免费   2086篇
  国内免费   823篇
耳鼻咽喉   435篇
儿科学   475篇
妇产科学   571篇
基础医学   1228篇
口腔科学   150篇
临床医学   2366篇
内科学   3885篇
皮肤病学   142篇
神经病学   1429篇
特种医学   494篇
外科学   3451篇
综合类   3813篇
预防医学   847篇
眼科学   107篇
药学   1355篇
  8篇
中国医学   115篇
肿瘤学   5597篇
  2024年   27篇
  2023年   388篇
  2022年   972篇
  2021年   1287篇
  2020年   1278篇
  2019年   866篇
  2018年   823篇
  2017年   891篇
  2016年   932篇
  2015年   877篇
  2014年   1859篇
  2013年   1529篇
  2012年   1663篇
  2011年   1773篇
  2010年   1359篇
  2009年   1317篇
  2008年   1283篇
  2007年   1240篇
  2006年   1110篇
  2005年   872篇
  2004年   717篇
  2003年   594篇
  2002年   432篇
  2001年   438篇
  2000年   384篇
  1999年   336篇
  1998年   223篇
  1997年   180篇
  1996年   130篇
  1995年   114篇
  1994年   82篇
  1993年   57篇
  1992年   63篇
  1991年   52篇
  1990年   41篇
  1989年   36篇
  1988年   42篇
  1987年   31篇
  1986年   15篇
  1985年   34篇
  1984年   26篇
  1983年   9篇
  1982年   20篇
  1981年   7篇
  1980年   18篇
  1979年   11篇
  1978年   6篇
  1976年   4篇
  1975年   4篇
  1972年   10篇
排序方式: 共有10000条查询结果,搜索用时 109 毫秒
1.
2.
3.
目的 探讨人胶质母细胞瘤(GBM)组织微小核糖核酸-4516(miR-4516)的表达情况及其与病人预后的关系。方法选取 2015年 1月~2019年 5月手术切除的 GBM组织 89例和颅脑损伤内减压术切除的非肿瘤脑组织 35例为对照组,采用 qRT-PCR检测 miR-4516的表达水平,根据 miR-4516表达水平的中位数分为高表达和低表达。GBM病人术后随访 2年,记录生存情况。结果 GBM组织 miR-4516表达水平([ 5.32±1.75)]明显高于对照组([ 1.13±0.45);P<0.01]。术后 2年随访,42例(47.19%)生存,47例 47(52.81%)死亡。多因素 Cox回归分析显示,miR-4516高表达是 GBM生存预后病例的独立危险因素(P<0.05)。生存曲线分析显示 miR-4516高表达组 2年累积生存率(27.45%)明显低于低表达组(73.68%;P<0.001)。结论 GBM组织 miR-4516表达增高,其高表达是病人预后不良的危险因素。  相似文献   
4.
BackgroundA comprehensive re-evaluation on the role of trans-arterial chemoembolization (TACE) in patients with intrahepatic cholangiocarcinoma.MethodsA thorough database searching was performed in PubMed, EMBASE, and the Cochrane Library. Eligible studies were restricted to comparative studies between TACE and non-TACE cohorts. RevMan5.3 software and Stata 13.0 software were used for statistical analyses. The primary endpoint of our study was long-term survival.ResultsA total of 11 studies with 2036 patients were finally identified. Pooled results revealed that patients receiving TACE had a significantly better overall survival (OS) versus those without TACE (P < 0.05). Subgroup analyses were performed according to different types of TACE. Prophylactic post-surgical TACE (PPTACE) was associated with a significantly better OS versus those without PPTACE (P < 0.05). Palliative TACE (PTACE) also achieved a significantly better OS compared with those with supportive treatment (ST) only (P < 0.00001). However, TACE had no impact on disease-free survival (P = 0.87) and was less effective than surgical resection (P = 0.003).ConclusionPPTACE has a remarkable impact on OS versus those with surgical resections only and should be regularly performed. Regarding patients with unresectable disease, apart from conventional ST, adjuvant PTACE is also recommended. Upcoming prospective randomized controlled trials are warranted for further validation.  相似文献   
5.
杨旭  朱德兵  王巍炜  唐明伟 《西部医学》2022,34(9):1329-1334+1341
目的 分析术前SCC、CYFRA21-1与肺鳞癌临床病理特征、预后之间的关系。方法 收集2017年3月~2018年4月在云南省肿瘤医院确诊的肺鳞癌患者100例为观察组,确诊为肺良性肿瘤患者90名为肺良性肿瘤组、以及正常人群90名为健康人群组。通过电化学发光法对SCC、CYFRA21-1两种指标进行检测。检测SCC、CYFRA21-1含量,分析在肺鳞癌中表达的临床意义。结果 SCC、CYFRA21-1在肺鳞癌中比在肺良性肿瘤、健康人群中含量要高,差异有统计学意义(P<0.001),并且敏感性均高于其他两组;男性患者的SCC、CYFRA21-1含量高于女性患者,差异具有统计学意义(P<0.05);SCC、CYFRA21-1含量在年龄≥60岁的含量高于<60岁患者,差异无统计学意义(P>0.05);有吸烟史患者的SCC含量高于无吸烟史患者,差异无统计学意义(P>0.05)。CYFRA21-1在吸烟史患者中高表达,差异有统计学意义(P<0.05);SCC、CYFRA21-1在有淋巴结转移、远处转移、肿瘤直径≥5 cm、病理分期为晚期时高表达,差异具有统计学意义(P<0.05);SCC、CYFRA21-1阳性患者OS、PFS比阴性患者短;SCC、CYFRA21-1两者之间呈正相关,相关系数(r)为0.630。结论 SCC、CYFRA21-1在肺鳞癌中表达上调;SCC、CYFRA21-1与性别之间存在某种内在联系;SCC、CYFRA21-1与肺鳞癌的TNM分期呈正相关;SCC、CYFRA21-1阳性患者OS、PFS比阴性患者短;SCC、CYFRA21-1两者之间呈正相关,相关系数(r)为0.630。  相似文献   
6.
目的筛选成骨型骨肉瘤与正常成骨细胞的差异表达基因, 寻找成骨型骨肉瘤发生、发展的关键基因。方法从Gene Expression Omnibus(GEO)数据库获得正常成骨细胞和骨肉瘤组织的基因表达数据集GSE33382, 采用R语言的limma包筛选正常成骨细胞和成骨型骨肉瘤的差异表达基因, 对差异表达基因进行京都基因与基因组百科全书(KEGG)通路富集分析。采用String数据库构建蛋白交互网络, 应用Cytoscape软件的分子复合物检测(MCODE)插件筛选互作网络中的网络模块, 应用Cytoscape软件中的BiNGO模块对MCODE筛选得到的前3个主要模块所包含的差异表达基因进行基因本体(GO)富集分析。采用MCC算法筛选蛋白互作网络中前10个关键基因。从GEO数据库获得骨肉瘤的基因表达和生存数据集GSE39055, 采用Kaplan-Meier法进行生存分析。选取2005年1月至2015年12月福建医科大学附属第一医院收治的48例成骨型骨肉瘤患者的资料进行验证, 采用免疫组化法测定骨肉瘤组织中STC2蛋白的表达, 结合患者的临床资料进行生存分析。结果从GSE33382数据集...  相似文献   
7.
We have updated recommendations on 12 controversial topics that were published in the 2013 National Consensus on the diagnosis, risk stratification and treatment of patients with pulmonary embolism (PE). A comprehensive review of the literature was performed for each topic, and each recommendation was evaluated in two teleconferences. For diagnosis, we recommend against using the Pulmonary Embolism Rule Out Criteria (PERC) rule as the only test to rule out PE, and we recommend using a D-dimer cutoff adjusted to age to rule out PE. We suggest using computed tomography pulmonary angiogram as the imaging test of choice for the majority of patients with suspected PE. We recommend using direct oral anticoagulants (over vitamin K antagonists) for the vast majority of patients with acute PE, and we suggest using anticoagulation for patients with isolated subsegmental PE. We recommend against inserting an inferior cava filter for the majority of patients with PE, and we recommend using full-dose systemic thrombolytic therapy for PE patients requiring reperfusion. The decision to stop anticoagulants at 3 months or to treat indefinitely mainly depends on the presence (or absence) and type of risk factor for venous thromboembolism, and we recommend against thrombophilia testing to decide duration of anticoagulation. Finally, we suggest against extensive screening for occult cancer in patients with PE.  相似文献   
8.
Cervical cancer is a global health challenge in women. Neoadjuvant chemotherapy (NACT) is a recent prospect for alternative cervical cancer treatments. This study investigated the efficacy of NACT against resectable cervical cancer based on the medium and long-term survival of patients with the disease. We searched through PubMed, Web of Science, EBSCO and Cochrane Library for relevant reports published by June 2020. The primary outcomes were 3-year and 5-year progression-free survival (PFS) and overall survival (OS) of patients with resectable cervical cancer. Overall, 22 publications encompassing 5627 patients fulfilled the inclusion criteria. We found NACT not to affect both 3-year PFS and OS as well as 5-year PFS of patients with resectable cervical cancer. However, NACT significantly improves the 5-year OS of patients with resectable cervical cancer (HR = 0.83, 95% CI: 0.73–0.94, p = 0.013). Subgroup analysis (RCTs, non-RCTs, NACT + surgery + AT vs. surgery + AT, NACT + surgery + AT vs. CCRT/RT/CRT) further revealed NACT had no significant effect on 5-year PFS of patients with resectable cervical cancer, converse to the 5-year OS subgroup analysis, which validated the beneficial effect of NACT in patients with resectable cervical cancer. In addition, the effect of NACT was most significant in the non-RCTs subgroup (p = 0.012). NACT may improve the long-term prognosis of patients with resectable cervical cancer. However, further large-scale multicenter studies are needed to validate this finding.  相似文献   
9.
目的 探讨长链非编码RNA(lncRNA)FTX表达水平与脑胶质瘤病人预后的相关性。方法 前瞻性收集2016年1月~2018年1月手术切除的脑胶质瘤88例(46例获得瘤旁组织),采用实时逆转录PCR检测lncRNA FTX表达水平,以脑胶质瘤组织lncRNA FTX表达水平均值为界分为高表达组(n=57)和低表达组(n=31)。术后随访3年,主要观察指标为无进展生存期、总生存期。结果 脑胶质瘤组织lncRNA FTX表达水平[(7.54±2.15)]明显高于瘤旁组织[(2.65±0.69);P<0.001]。多因素Cox比例回归风险模型分析显示,lncRNA FTX高表达是脑胶质瘤生存预后不良的独立危险因素(RR=1.589;95% CI 1.004~2.515;P=0.048)。生存曲线分析显示,高表达组无进展生存期(15.10个月)和总生存期(20.24个月)较低表达组(分别为18.96和25.53个月)明显缩短(P<0.05)。结论 脑胶质瘤lncRNA FTX呈高表达,与病人不良生存预后有关。  相似文献   
10.
Localized gastric amyloidosis (LGA) is a rare disease characterized by abnormal extracellular deposition of amyloid protein restricted to the stomach and it is confirmed by positive results of Congo red staining. Over decades, only a few cases have been reported and studies or research focusing on it are few. Although LGA has a low incidence, patients may suffer a lot from it and require proper diagnosis and management. However, the pathology of LGA remains unknown and no overall review of LGA from its presentations to its prognosis has been published. Patients with LGA are often asymptomatic or manifest atypical symptoms, making it difficult to differentiate from other gastrointestinal diseases. Here, we report the case of a 70-year-old woman with LGA and provide an overview of case reports of LGA available to us. Based on that, we conclude current concepts of clinical manifestations, diagnosis, treatment, and prognosis of LGA, aiming at providing a detailed diagnostic procedure for clinicians and promoting the guidelines of LGA. In addition, a few advanced technologies applied in amyloidosis are also discussed in this review, aiming at providing clinicians with a reference of diagnostic process. With this review, we hope to raise awareness of LGA among the public and clinicians.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号