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   718708篇
  免费   67509篇
  国内免费   20332篇
耳鼻咽喉   9776篇
儿科学   15750篇
妇产科学   12885篇
基础医学   52199篇
口腔科学   15483篇
临床医学   70924篇
内科学   88509篇
皮肤病学   7480篇
神经病学   23388篇
特种医学   25947篇
外国民族医学   347篇
外科学   114071篇
综合类   96228篇
现状与发展   83篇
一般理论   31篇
预防医学   52893篇
眼科学   10827篇
药学   62315篇
  687篇
中国医学   37647篇
肿瘤学   109079篇
  2024年   857篇
  2023年   12189篇
  2022年   18073篇
  2021年   33388篇
  2020年   30122篇
  2019年   32936篇
  2018年   27959篇
  2017年   26744篇
  2016年   28729篇
  2015年   32450篇
  2014年   55175篇
  2013年   53452篇
  2012年   49937篇
  2011年   48682篇
  2010年   40304篇
  2009年   38168篇
  2008年   36406篇
  2007年   36025篇
  2006年   31210篇
  2005年   24482篇
  2004年   18270篇
  2003年   15499篇
  2002年   12559篇
  2001年   10915篇
  2000年   9346篇
  1999年   7405篇
  1998年   6436篇
  1997年   5724篇
  1996年   4665篇
  1995年   4765篇
  1994年   4248篇
  1993年   3394篇
  1992年   3367篇
  1991年   3054篇
  1990年   2650篇
  1989年   2524篇
  1988年   2306篇
  1987年   2082篇
  1986年   1739篇
  1985年   3744篇
  1984年   4065篇
  1983年   2727篇
  1982年   3233篇
  1981年   2694篇
  1980年   2316篇
  1979年   1997篇
  1978年   1575篇
  1977年   1367篇
  1976年   1371篇
  1975年   945篇
排序方式: 共有10000条查询结果,搜索用时 20 毫秒
991.
目的:研究小核糖体核蛋白B(small nuclear ribonucleoprotein polypeptides B and B1,SNRPB)在乳腺癌中的表达及临床意义。方法:运用Oncomine数据库搜索乳腺癌与SNRPB基因相关的数据,通过Kaplan-Meier Plotter数据库分析SNRPB基因与乳腺癌患者预后的关系。结果:Oncomine数据库中SNRPB基因癌组织/正常组织表达量分析结果共有414个,在癌组织中显著高表达109个,低表达3个。其中13个分析结果显示SNRPB在乳腺癌组织(包括6个侵袭性乳腺癌分析结果)中显著高表达,低表达的分析结果为1个。运用Kaplan-Meier Plotter数据库分析结果显示,高表达SNRPB的乳腺癌患者其总体生存率(OS)、无复发生存率(PFS)、无远处转移生存率(DMFS)显著低于低表达SNRPB的乳腺癌患者(P<0.05)。结论:SNRPB基因在乳腺癌中高表达,可以作为有效的生物标志物预测乳腺癌患者转移的发生及判断预后,可为乳腺癌的靶向治疗提供依据。  相似文献   
992.
目的:分析乳腺癌患者的CYP2D6基因多态性和代谢表型,为乳腺癌患者进行他莫西芬(TAM)个体化临床治疗提供参考依据。方法:选取2018年1月至2019年1月于我院乳腺科确诊的170例乳腺癌患者外周血,通过Sanger测序技术对CYP2D6基因的9个外显子进行全面具体分析。结果:本研究主要发现有5个CYP2D6等位基因变异位点:CYP2D6*10、CYP2D6*4、CYP2D6*7、CYP2D6*41和CYP2D6*5,其对应的发生频率分别为66.5%、5.9%、2.4%、0.6%和0.6%;其中,CYP2D6*10/*10基因型在乳腺癌患者中占据主导地位,发生频率为60.6%。结论:中国甘肃地区乳腺癌患者,多以CYP2D6*10等位基因、CYP2D6*10/*10基因型、TAM中间代谢型为主,这可为乳腺癌患者选择相应的个体化药物治疗方案以及本地区乳腺癌患者今后大规模的药物遗传基因组学研究提供参考数据。  相似文献   
993.
目的:应用生物信息学方法挖掘胶质母细胞瘤(GBM)的相关基因,进而探讨发病机制,为GBM临床诊断和靶向治疗提供理论依据。方法:从GEO(Gene Expression Omnibus)数据库下载基因芯片数据集GSE4290和GSE15824,应用GEO2R筛选GBM的差异表达基因(DEGs)。采用DAVID数据库进行GO富集和KEGG通路富集分析,分别应用STRING数据库和Cytoscape软件构建蛋白质相互作用网络和关键基因模块,筛选GBM靶基因。进一步运用ONCOMINE数据库验证临床组织样本中靶基因与GBM的关系。结果:共筛选出76个DEGs,富集分析结果显示DEGs在血管生成的正调节、抗原的呈递和处理、信号转导、调节自噬等方面存在显著富集。共挖掘出POSTN、TAGLN、CALD1、EPCAM 4个GBM靶基因,经证实均在临床GBM组织样本中存在显著上调且靶基因的上调与患者的不良预后密切相关。结论:通过生物信息学共挖掘出4个与GBM显著相关的靶基因,可能是未来GBM发病机制、临床诊断、治疗的重要研究靶点。  相似文献   
994.
《Clinical lung cancer》2020,21(6):545-552.e1
BackgroundOutcomes of therapy targeting molecular driver alterations detected in advanced non–small-cell lung (NSCLC) using circulating tumor DNA (ctDNA) have not been widely reported in patients who are targeted therapy-naive.Patients and MethodsWe performed a multicenter retrospective review of patients with unresectable stage IIIB to IV NSCLC who received matched therapy after a targetable driver alteration was identified using a commercial ctDNA assay through usual clinical care. Eligible patients must not have received targeted therapy prior to ctDNA testing (prior chemotherapy or immunotherapy was permitted). Kaplan-Meier analysis was used to estimate the median duration of targeted therapy. Patients still on targeted therapy were censored at last follow-up.ResultsSeventy-six patients met inclusion criteria. The median age of diagnosis of NSCLC was 64.5 years (range, 31-87 years), 67% were female, 74% were never-smokers, and 97% had adenocarcinoma histology. Twenty-one (28%) patients received systemic treatment prior to targeted therapy, including chemotherapy (n = 17), immunotherapy (n = 5), and/or a biologic (n = 4). Thirty-three (43%) patients remain on targeted therapy at the time of data analysis. The median time on targeted therapy was similar to what has been reported for tissue-detected oncogenic driver mutations in the targeted therapy-naive setting.ConclusionsPatients with ctDNA-detected drivers had durable time on targeted therapy. These treatment outcomes data compliment previous studies that have shown enhanced targetable biomarker discovery rates and high tissue concordance of ctDNA testing when incorporated at initial diagnosis of NSCLC. Identification of NSCLC driver mutations using well-validated ctDNA assays can be used for clinical decision-making and targeted therapy assignment.  相似文献   
995.
《Clinical breast cancer》2020,20(2):e181-e187
BackgroundT-DM1 improves progression-free survival (PFS) and overall survival (OS) in patients with metastatic human epidermal growth factor receptor 2-positive (HER2+) breast cancer progressing on prior trastuzumab plus a taxane. A paucity of data is available on T-DM1 efficacy after dual anti-HER2 blockade with pertuzumab and trastuzumab plus a taxane, which represents the current first-line standard of care. The present study is a retrospective/prospective evaluation of the efficacy and activity of second-line T-DM1 after front-line pertuzumab-based therapy.Patients and MethodsEligible patients were identified within the Gruppo Italiano Mammella (GIM) 14/BIOMETA study, a retrospective/prospective multicenter study on treatment patterns and outcomes of patients with metastatic breast cancer (ClinicalTrials.gov Identifier: NCT02284581). We searched for patients who received second-line T-DM1 after taxane plus trastuzumab and pertuzumab between November 15, 2013 and May 31, 2018. We calculated median PFS, median time to treatment failure (TTF), prolonged duration of therapy (PDT), objective response rate (ORR), and 1-year OS.ResultsOf 445 patients with HER2+ metastatic breast cancer, 77 were eligible for the analysis. At a median follow-up of 7 months, median PFS was 6.3 months (95% confidence intervals [CI], 4.8-7.7 months), and median TTF was 6.2 months (95% CI, 4-8.6 months). More than one-third of patients (37.6%; n = 29) experienced PDT with an ORR of 27.1%. At data cutoff, the median OS was not reached, and the 1-year OS was 82%.ConclusionsOur results show meaningful activity of T-DM1 after front-line pertuzumab plus trastuzumab and a taxane, with about 27% of patients having an objective response and 40% of patients achieving durable disease control.  相似文献   
996.
《Clinical colorectal cancer》2020,19(4):236-247.e6
BackgroundThe multicenter, single-arm, phase II study CEBIFOX evaluated the efficacy of a biweekly cetuximab administration in combination with FOLFOX6 as first-line therapy in KRAS (exon 2) wild-type (wt) metastatic colorectal cancer (mCRC).Patients and methodsPatients received FOLFOX6 with cetuximab (500 mg/m2) every second week. Primary endpoint was objective response rate (ORR), among others secondary endpoints were safety, progression-free survival (PFS), overall survival (OS), and patient-reported outcome (PRO). The impact on the treatment efficacy was evaluated in explorative subgroup analyses, including extended molecular profiling and primary tumor location.ResultsIn total, 57 were included in the intention-to-treat (ITT) analyses. New RAS mutations were detected in 14.0% by post hoc next-generation sequencing analysis in 43 patients. The ORR in the all RASwt population was 70.3% with a median PFS and OS of 10.9 (95% confidence interval [CI], 9.0-12.9) and 33.8 (95% CI, 21.1-45.5) months. Grade 3-5 adverse events occurred in 66.7% of the ITT, without significant impact on the PRO. Patients with right-sided primary tumors had a reduced ORR (54.5%), and median PFS and OS (10.1 and 23.8 months). BRAF mutations were detected in 11.3%. These patients had a significantly lower ORR, and median PFS and OS. Patients with RASwt/BRAFwt tumors had a notably high median PFS and OS of 14.3 and 38.9 months.ConclusionsThis study supports the efficacy and safety of biweekly cetuximab given in combination with FOLFOX6 in patients with RASwt/BRAFwt mCRC with left-sided primary tumor. CEBIFOX is the first trial reporting the complete dataset, including extended molecular profiling and tumor location of a biweekly administered cetuximab/FOLFOX6 in mCRC. Clinical trial number: NCT01051167.  相似文献   
997.
Purpose: An exploration of concurrent chemoradiation therapy care process from the perspective of patients with head and neck cancer can provide an insight to their lived experience and the difficulties they encounter in daily life towards a deeper understanding of this phenomenon to shape nursing service delivery. The aims of this study were to explore the lived experiences of patients with head and neck cancer while receiving concurrent chemoradiation therapy. Methods: Data were generated from individual in-depth interviews with fifteen head and neck cancer patients, according to the semi-structured interview guidelines, at the out-patient radiation oncology department, Chulabhorn Cancer Center, Bangkok, Thailand. Results: By using Graneheim and Lundman’s content analysis, three categories from the data analysis of patients with head and neck cancer receiving concurrent chemoradiation therapy were isolated: 1) overwhelming information, 2) unpleasant symptom cluster, and 3) strategy for adherence to treatment regimen. Conclusion: The findings help to provide a better understanding of the lived experiences of patients with head and neck cancer during concurrent chemoradiation therapy, in terms of their suffering from various unpleasant side effects and how these impact their life along the treatment journey. This perspective on the care process in these patients enhances the development of a nursing care model based on patient-centered care toward positive patient outcomes.  相似文献   
998.
ATP6L, the C subunit of the V‐ATPase V0 domain, is involved in regulating the acidic tumor micro‐environment and may promote tumor progression. However, the expression and functional role of ATP6L in tumors have not yet been well explored. In this study, we found that ATP6L protein overexpression was related to colorectal cancer histological differentiation (P < 0.001), presence of metastasis (P < 0.001) and recurrence (P = 0.02). ATP6L expression in the liver metastatic foci was higher than in the primary foci (P = 0.04). ATP6L expression was notably concomitant with epithelial‐mesenchymal transition (EMT) immunohistochemical features, such as reduced expression of the epithelial marker E‐cadherin (P = 0.021) and increased expression of the mesenchymal marker vimentin (P = 0.004). Results of in vitro and in vivo experiments showed that ATP6L expression could alter cell morphology, regulate EMT‐associated protein expression, and enhance migration and invasion. The effect of ATP6L on metastasis was further demonstrated in a tail vein injection mice model. In addition, the mouse xenograft model showed that ATP6L‐overexpressing HCT116 cells grew into larger tumor masses, showed less necrosis and formed more micro‐vessels than the control cells. Taken together, our results suggest that ATP6L promotes metastasis of colorectal cancer by inducing EMT and angiogenesis, and is a potential target for tumor therapy.  相似文献   
999.
1000.
目的研究情境模拟案例教学法在护士规范化培训中的应用效果。方法选择2017年8月-2018年7月在医院外科系统进行规范化培训的护士60名作为对照组,接受常规模式的规范化培训;而选择2018年8月-2019年7月进行规范化培训的护士60名作为研究组,在规培期间引入情境模拟案例教学法。规培结束后,考核并比较两组规培护士的理论知识和临床护理操作,测评规培护士的评判性思维能力,调查规培护士对规培模式的满意度。结果对照组的理论知识和临床护理操作的得分分别是(86.7±7.5)分、(82.8±8.7)分,而研究组的得分则分别是(91.3±8.4)分、(87.5±8.1)分;与对照组相比,研究组护士对理论知识的掌握和临床护理操作技能更强(P<0.05)。与对照组相比,研究组规培护士具有更强的批判性思维能力(P<0.05)。而且,研究组护士对情境模拟案例教学模式的满意度要优于对照组(P<0.05)。结论情境模拟案例教学法在护士规范化培训中效果较好,可显著提高规培护士的理论及实践操作的综合能力以及评判性思维能力。  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