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   7726篇
  免费   947篇
  国内免费   1554篇
耳鼻咽喉   124篇
儿科学   38篇
妇产科学   71篇
基础医学   805篇
口腔科学   36篇
临床医学   972篇
内科学   1322篇
皮肤病学   298篇
神经病学   587篇
特种医学   421篇
外国民族医学   2篇
外科学   1445篇
综合类   1793篇
现状与发展   1篇
预防医学   304篇
眼科学   454篇
药学   425篇
  1篇
中国医学   128篇
肿瘤学   1000篇
  2024年   8篇
  2023年   147篇
  2022年   216篇
  2021年   295篇
  2020年   285篇
  2019年   180篇
  2018年   199篇
  2017年   177篇
  2016年   227篇
  2015年   385篇
  2014年   620篇
  2013年   574篇
  2012年   745篇
  2011年   833篇
  2010年   608篇
  2009年   542篇
  2008年   451篇
  2007年   281篇
  2006年   222篇
  2005年   321篇
  2004年   343篇
  2003年   479篇
  2002年   614篇
  2001年   450篇
  2000年   167篇
  1999年   152篇
  1998年   129篇
  1997年   121篇
  1996年   68篇
  1995年   16篇
  1994年   67篇
  1993年   52篇
  1992年   66篇
  1991年   77篇
  1990年   47篇
  1989年   34篇
  1988年   26篇
  1987年   2篇
  1986年   1篇
排序方式: 共有10000条查询结果,搜索用时 153 毫秒
1.
BackgroundData on adult sexual functioning after kidney transplantation (KTx) during childhood or adolescence are scarce.AimTo assess the long-term sexual and psychosocial quality of life after pediatric KTx.Methods29 young men (median age 27.1 years) were examined 18.7 years (median) after KTx. 56 age-matched healthy men (median age 30.0 years) served as controls.OutcomeWe studied the influence of sociodemographics, previous renal replacement therapy, current reproductive hormonal serum levels, testicular size, and data on several validated mental and physical questionnaires on participants' Derogatis Interview for Sexual Functioning self-report scores.ResultsThe KTx recipients had significantly poorer sexual functioning than their healthy peers. KTx men had less frequent sexual activity with a partner (P = .03) and poorer orgasms (P = .002) than the controls but no erectile dysfunction (P = .5).Clinical implicationsDepressive symptoms, relationship status, and longer dialysis duration predicted poor adult sexual functioning in KTx recipients, whereas age at transplantation or at the time of the study did not.Strengths & LimitationsThis study contributes extended follow-up data to the very scarce literature on adult sexual functioning in pediatric KTx recipients. Relatively small population and low participation rate limit the comprehensive data interpretation in a population-based cohort of male KTx recipients.ConclusionSexual functioning is often impaired in young men after pediatric KTx, emphasizing the need for long-term monitoring of sexual health and sexuality as important dimensions of quality of life.Tainio J, Jahnukainen T, Jalanko H, et al. Male Sexual Function After Pediatric Kidney Transplantation—A Cross-sectional Nationwide Study. J Sex Med 2020;17:2104–2107.  相似文献   
2.
目的:探讨新生血管特异性结合肽GX1二聚体对胃癌新生血管生成的影响。方法:化学合成GX1二聚体、GX1单体、对照肽二聚体,CCK-8实验、管状结构形成实验、迁移实验研究GX1二聚体对胃癌血管内皮细胞(co-HUVEC)增殖、微管形成、迁移能力的影响,流式细胞学技术分析其对细胞周期分布和凋亡的影响。结果:CCK-8结果显示,GX1二聚体与对照肽二聚体及PBS对照组相比,100~200 μmol/L可抑制co-HUVEC增殖,具有统计学差异(P<0.05),并呈剂量依赖性,GX1二聚体较单体抑制作用增强,并有统计学差异(P<0.05)。管状结构形成实验、细胞损伤迁移实验结果显示,与对照肽二聚体及对照组PBS 相比,GX1二聚体及GX1单体,均可抑制胃癌内皮细胞管状结构的形成及迁移,且二聚体抑制作用强于单体;对照肽二聚体仅有轻微的抑制胃癌内皮细胞管状结构的形成及迁移。流式细胞术分析显示,与对照肽二聚体及PBS对照组相比,GX1二聚体及GX1单体均可诱导细胞凋亡(P<0.05),且GX1二聚体的诱导作用强于GX1单体(P<0.05),而对细胞周期分布则无明显影响。结论:GX1二聚体和GX1单体均可抑制胃癌新生血管内皮细胞增殖、微管形成、迁移能力及诱导凋亡,且GX1二聚体较GX1单体作用增强。GX1二聚体有望代替单体成为胃癌新生血管靶向治疗小肽类药物。  相似文献   
3.
4.
PurposeType B aortic dissection is a rare but life-threatening disease. Thoracic endovascular aortic repair (TEVAR) was widely used for Type B aortic dissection patients in the last decade due to the lower mortality and morbidity compared with open chest surgical repair (OCSR). AKI in type B aortic dissection is a well-recognized complication and indicates poor short-term and long-term outcome. The objective of this concise review was to identify the risk factors and the impact of AKI on type B aortic dissection patients.Methods and resultsA literature search was performed using PubMed, Embase, MEDLINE, and Cochrane Library with the search terms ‘type B aortic dissection’ and ‘acute kidney injury’ (AKI), and all English-language literatures published in print or available online from inception through August 2020 were thoroughly reviewed. Studies that reported relative AKI risks and outcomes in type B aortic dissection patient were included. Major mechanisms of AKI in type B aortic dissection included renal hypoperfusion, inflammation response, and the use of contrast medium. Type B aortic dissection patients with AKI significantly had increased hospital stay duration, need of renal replacement therapy, and 30-d and 1-year mortality.ConclusionsAKI in type B aortic dissection is a well-recognized complication and associated with poor short-term and long-term outcome. Early identification of high-risk patients, early diagnosis of AKI, stabilization of the hemodynamic parameters, avoidance of nephrotoxic drugs, and optimization of the use of contrast agents are the major strategies for the reduction of AKI in type B aortic dissection patients.  相似文献   
5.
目的:探讨乳腺弥漫大B细胞淋巴瘤(DLBCL)患者的临床特征及预后。方法:回顾性分析2014年5月起至2018年12月我院收治的18例乳腺DLBCL患者的临床特点及预后。结果:在18例患者中,17例为女性,中位年龄为57岁,病变主要累及右侧乳腺(11/18,61.1%)。将其分为原发性乳腺DLBCL(PB-DLBCL)和继发性乳腺DLBCL(SB-DLBCL)两大类。11例(57.6%)PB-DLBCL与7例(42.4%)SB-DLBCL相比,其具有Ann Arbor分期多为Ⅰ-Ⅱ期(P<0.01)、B症状少(P=0.013)、相对更高的白细胞计数(P=0.041)、骨髓未累及(P=0.043)、完全缓解(CR)率高(P=0.049)等特点。生存分析发现PB-DLBCL患者5年总生存期(OS)显著长于SB-DLBCL患者(P=0.013)。本研究以非生发中心B细胞型(non-GCB)居多,生发中心型(GCB)与non-GCB型之间OS无显著差异(P=0.885)。所有获得CR患者的生存期均显著延长(P=0.008)。结论:乳腺DLBCL多见于中年女性,以右侧乳腺肿块为主要临床表现,分子分型多为non-GCB型。与SB-DLBCL患者相比,PB-DLBCL患者具有Ann Arbor分期早、B症状少、相对更高的白细胞计数、骨髓未累及、CR率高等特点,并且生存期显著延长。无论是PB-DLBCL和SB-DLBCL,还是GCB型和non-GCB型,获得CR提示预后良好。  相似文献   
6.
7.
目的:利用整合生物信息学手段分析EZH2(enhancer of zeste 2 polycomb repressive complex 2 subunit)基因在乳腺癌中的表达及其临床意义。方法:在肿瘤基因组计划数据库(The Cancer Genome Atlas,TCGA)中下载乳腺癌与正常乳腺组织的基因表达谱数据,进一步利用Ualcan数据库和人类蛋白质图谱(The Human Protein Atlas)数据库数据分析EZH2基因在乳腺癌中的mRNA及蛋白表达水平。利用Ualcan数据库分析EZH2基因的甲基化水平并筛选其共表达基因;对EZH2及其共表达基因进行GO(Gene Ontology)富集分析和KEGG通路分析以明确EZH2的共表达基因参与的生物学过程和相关通路;使用Kaplan-Meier生存分析法分析乳腺癌患者的总生存期、无病生存期、无远处转移生存期及后进展生存期与EZH2基因表达水平的关系并绘制生存曲线。结果:与正常乳腺组织相比,EZH2在乳腺癌组织中的mRNA及蛋白表达量明显升高。而EZH2的甲基化程度在乳腺癌组织与正常乳腺组织中则差异不明显。同时,EZH2的表达水平与年龄、乳腺癌分期及乳腺癌分子分型等因素密切相关。EZH2及其共表达基因主要参与了核碱基的调节、细胞周期调控、染色体分离、DNA复制、DNA修复等生物学过程,并参与了细胞周期、DNA 复制、M/G1期转化、M期、有丝分裂前中期、ATM通路等生物学通路。此外,EZH2基因表达水平高的乳腺癌患者的总生存期、无病生存期、无远处转移生存期及后进展生存期均明显低于EZH2基因低表达的患者。结论:EZH2在乳腺癌组织中高表达并且与患者不良预后密切相关。同时,EZH2的表达水平与乳腺癌的发生、发展密切相关。EZH2在乳腺癌诊断、靶向治疗及预后分析中具有重要的临床意义。  相似文献   
8.
BackgroundFOLFIRI (irinotecan, 5-fluorouracil, and leucovorin) + aflibercept improves median overall survival (OS) and progression-free survival (PFS) in patients with previously treated metastatic colorectal cancer (mCRC). Our aim was to investigate efficacy and tolerability of this combination in the first line.Patients and MethodsPatients with untreated documented mCRC received aflibercept plus FOLFIRI every 14 days until progression or unacceptable toxicity in an open, phase II single-arm, multicenter trial. The primary endpoint was the 6-month PFS rate. Secondary endpoints were OS and tolerability. A 2-step Simon design was used with H0: 55% and H1= 75%. Data were analyzed in intention to treat.ResultsForty-one patients were included, and 40 were analyzed (1 consent withdrawal) in 9 French centers between October 2014 and February 2017. The median age was 65 years (range, 46-81 years), 55% had ≥ 2 metastatic sites, and 50% and 15% had RAS and BRAF mutations, respectively. Twenty-two (54.5%; 95% confidence interval, 38.9%-68.5%) patients were alive and non-progressive at 6 months. FOLFIRI + aflibercept was considered ineffective, resulting in the cessation of inclusions. The median follow-up was 34 months. The overall response rate was 55%, and the disease control rate was 80%. The median duration of treatment was 5.3 months; the median PFS and OS were 8.2 and 18.6 months, respectively. Grade 3 to 4 adverse events were mainly gastrointestinal (47.5%) and vascular (32.5%). Of the patients, 87.5% had at least 1 dose modification.ConclusionAlthough the primary objective was not met, first-line FOLFIRI + aflibercept for mCRC leads to median PFS and OS close to those reported with classical doublet and targeted agents, but with significant toxicities needing dose reduction.  相似文献   
9.
目的探讨T3、T4期结直肠癌患者淋巴结转移危险因素,为临床诊疗提供参考。方法回顾性分析2008年1月至2017年12月在空军军医大学西京消化病医院行结直肠癌根治术的1112例T3、T4期结直肠癌患者的临床病理资料,分析淋巴结转移状态与临床病理因素及肿瘤标志物的相关性,应用logistic多因素回归法分析淋巴结转移的相关危险因素。结果单因素分析结果显示,性别、年龄、肿瘤部位分层的结直肠癌患者间淋巴结转移率差异均无统计学意义(均P>0.05),淋巴结转移率在不同肿瘤长径[<5 cm和≥5 cm分别为37.75%(211/559)、52.26%(289/553),χ^2=23.666,P<0.01]、大体类型[浸润、溃疡、蕈伞、隆起分别为37.04%(20/54)、47.52%(432/909)、34.33%(23/67)、69.51%(57/82),χ^2=13.787,P=0.003]、分化程度[高、中、低分化分别为34.11%(102/299)、49.00%(317/647)、48.80%(81/166),χ^2=19.771,P<0.01]、错配修复缺陷(dMMR)[是和否分别为26.34%(64/243)、50.17%(436/869),χ^2=43.996,P<0.01]、神经侵犯[是和否分别为48.17%(421/874)、33.20%(79/238),χ^2=16.954,P<0.01]、脉管侵犯[是和否分别为79.16%(338/427)、23.65%(162/685),χ^2=327.493,P<0.01]以及术前癌胚抗原(CEA)[阳性(≥5 mg/ml)和阴性(<5 mg/ml)分别为52.87%(249/471)、39.16%(251/641),χ^2=20.162,P<0.01]和CA199[阳性(≥35 U/ml)和阴性(<35 U/ml)分别为59.33%(124/209)、41.64%(376/903),χ^2=21.465,P<0.01]分层患者间差异均有统计学意义。logistic多因素回归分析显示,脉管侵犯和术前CA199阳性是T3、T4期结直肠癌患者淋巴结转移独立危险因素(OR=13.006,95%CI 9.329~17.276,P<0.01;OR=2.194,95%CI 1.513~3.181,P<0.01),dMMR阳性是淋巴结转移的保护性因素(OR=0.279,95%CI 0.190~0.411,P<0.01)。结论脉管侵犯是T3、T4期结直肠癌患者淋巴结转移的主要危险因素。术前肿瘤标志物CA199的检测可以作为预测T3、T4期结直肠癌患者淋巴结转移状态的指标,一定程度上可为诊疗方案的制订提供参考。  相似文献   
10.
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