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   37388篇
  免费   2292篇
  国内免费   656篇
耳鼻咽喉   178篇
儿科学   472篇
妇产科学   456篇
基础医学   1842篇
口腔科学   191篇
临床医学   3556篇
内科学   3663篇
皮肤病学   512篇
神经病学   1361篇
特种医学   523篇
外国民族医学   1篇
外科学   1827篇
综合类   4570篇
一般理论   1篇
预防医学   4840篇
眼科学   267篇
药学   12556篇
  20篇
中国医学   1057篇
肿瘤学   2443篇
  2023年   425篇
  2022年   932篇
  2021年   1152篇
  2020年   1043篇
  2019年   950篇
  2018年   987篇
  2017年   1014篇
  2016年   1052篇
  2015年   1205篇
  2014年   2699篇
  2013年   3195篇
  2012年   2658篇
  2011年   2976篇
  2010年   2200篇
  2009年   2077篇
  2008年   2110篇
  2007年   1960篇
  2006年   1650篇
  2005年   1366篇
  2004年   1090篇
  2003年   965篇
  2002年   712篇
  2001年   651篇
  2000年   540篇
  1999年   524篇
  1998年   376篇
  1997年   350篇
  1996年   286篇
  1995年   303篇
  1994年   301篇
  1993年   200篇
  1992年   213篇
  1991年   151篇
  1990年   146篇
  1989年   124篇
  1988年   136篇
  1987年   130篇
  1986年   147篇
  1985年   164篇
  1984年   190篇
  1983年   90篇
  1982年   114篇
  1981年   88篇
  1980年   93篇
  1979年   72篇
  1978年   81篇
  1977年   77篇
  1976年   89篇
  1975年   79篇
  1974年   55篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
31.
Rheumatoid arthritis (RA) is considered a debilitating disease that increases the risk of significant morbidity and premature mortality. To circumvent drug-related toxicity and ineffectiveness of anti-inflammatory drugs, there is a significant need for an advanced delivery system that increases bioavailability. The feasibility of in situ gel of methotrexate sodium (MTS) as an effective management for Rheumatoid arthritis was investigated. It was formulated with pluronic F-127 (PLF-127) as primary polymer, hydroxypropyl methylcellulose K4M (HK4M), and polycarbophil (PCL) as a copolymer and characterized by various parameters. The efficacy evaluation by Freund's complete adjuvant (FCA) model, biocompatibility assessment by histopathological studies conducted. The optimized in situ gel (M4) was thermoresponsive, released 93.26 ± 2.39% MTS at 96 hours. In addition, distribution of MTS was even in the optimized sterile and syringeable in situ gel. In vivo studies on wistar rats demonstrated a substantial reduction in paw oedema during the 28-day study period and were biocompatible with the tissues at the injection site. The study was successful in formulating, optimizing MTS in situ gel for effective management of RA.  相似文献   
32.
吕丽  林劼 《肿瘤防治研究》2020,47(4):243-250
近年来,免疫治疗在多种恶性肿瘤治疗中取得突破性进展,为肿瘤患者带来明显生存获益。然而,免疫系统在识别和杀伤肿瘤细胞的同时,出现免疫编辑诱导,导致大多数患者对免疫治疗具有先天或后天的耐药性。肿瘤免疫编辑是免疫系统抑制或促进肿瘤发生发展的过程,肿瘤的发生发展经历了免疫消除、免疫平衡和免疫逃逸三个阶段。在整个过程中,肿瘤的免疫原性被编辑,并获得使疾病进展的各种免疫抑制机制,致使肿瘤细胞逃避免疫系统的监测,导致肿瘤细胞免疫逃逸产生耐药。因此,揭示肿瘤免疫治疗耐药机制及克服耐药至关重要。本文主要从肿瘤免疫编辑过程背后的机制对肿瘤免疫治疗耐药作一具体阐述,为临床中克服免疫耐药取得更好疗效提供参考。  相似文献   
33.
34.
Cervical squamous cell carcinoma and endocervical adenocarcinoma (CESC) is the fourth commonest female malignancy worldwide. CESC progresses in immune-microenvironment mainly composed of infiltrating immune and stromal cells. Here, we performed an integrated analysis incorporating the expression profiles from the Cancer Genome Atlas (TCGA) database and scores of immune and stromal cells calculated by Estimation of Stromal and Immune cells in Malignant Tumours using Expression data (ESTIMATE) algorithm. A two-gene signature (CD1C and CD6 genes) was established to predict the prognosis of CESC. Based on this signature, patients were divided into the high- and low-risk groups, and this signature showed good prognostic performance according to the results of Kaplan-Meier analysis and receiver operating characteristic (ROC) analysis in train set and two validation sets. A nomogram was built for evaluating the clinical applicability of this signature. In addition, based on Tumor Immune Estimation Resource (TIMER) database, 2 hub genes showed negative correlations with tumor purity and positive correlations with infiltrating levels of immune filtrating cells. What’s more, we propose new treatment strategies for the two prognostic subtypes. Low- risk patients were found presenting with a higher level of immune checkpoint molecules and showing higher immunogenicity in immunophenoscore (IPS) analysis, which indicated a better response for immunotherapy. Meanwhile, estimated by Genomics of Drug Sensitivity in Cancer (GDSC) database, the high-risk patients showed sensitive responses to five chemotherapy drugs. Finally, 10 candidate small-molecule drugs for CESC were defined. In summary, the CD1C-CD6 signature can accurately predict the prognosis of CESC.  相似文献   
35.
目的探究奥美拉唑所引起的不良反应及其与其他药物间的相互作用。方法122例接受奥美拉唑治疗并出现不良反应的患者,分析患者所处的环境状况、情绪状况、过敏史、年龄、过敏体质、生活习惯、饮酒情况等临床资料,探讨不良反应的发生原因,并分析不良反应累及系统分布情况及临床症状、导致不良反应的药物使用类型以及预后情况。结果122例奥美拉唑所致不良反应患者中,男性患者、年龄40~50岁、过敏体质、过敏史、情绪不稳定、药后饮酒、环境状况差占比相对较高。122例患者奥美拉唑所致不良反应中免疫系统占27.87%、消化道系统占23.77%、心脑血管系统占7.38%、神经系统占9.02%、血液系统占21.31%、肝胆系统占10.66%。患者常见临床症状为皮疹、瘙痒、皮炎、过敏性休克、恶心、呕吐、腹泻、心动过速、心律不齐、头晕、头痛、意识模糊、血小板下降、白细胞减少、血尿、肝功能障碍等。奥美拉唑与抗癫痫药苯妥英、抗惊厥药卡马西平、抗焦虑抗癫痫药地西泮以及安替比林药物相互作用,会使机体代谢功能降低,其发生可能与抑制钠离子内流有关。结论奥美拉唑所致不良反应会累及机体多个系统,因此医护人员应加强对患者的问诊,了解患者的相关情况,设计合理的用药方案,减少不良反应的发生。  相似文献   
36.
目的了解luminal型乳腺癌患者戈舍瑞林用药依从性情况,分析影响其依从性的相关因素。 方法根据纳入及排除标准,收集2015年1月至2017年12月重庆医科大学附属第一医院内分泌乳腺外科使用戈舍瑞林治疗的luminal型乳腺癌女性患者174例进行回顾性分析。中位随访时间16个月(范围:1~54个月),完成随访154例,失访20例,失访率为11.5%(20/174)。采用问卷调查评价其用药依从性,使用χ2检验和Mann-Whitney U检验比较不同特征患者依从性的差异;用Logistic回归分析影响患者依从性的相关因素。将患者分为≤40岁(103例)和>40岁(51例)2个亚组,进行亚组分析。 结果在完成随访的154例患者中,依从性好82例(53.2%,82/154),依从性差72例(46.8%,72/154)。≤40岁组患者中,55.3%(57/103)依从性好,而>40岁组患者中仅49.0%(25/51)依从性好。全部患者中,文化程度、医保类型、不良反应和是否了解疗程时间均与乳腺癌患者戈舍瑞林用药依从性有关(χ2=13.586、13.042、7.880、14.251,P均<0.050);Logistic回归分析结果显示:高中及以下学历、居民医保和不了解戈舍瑞林的疗程时间为影响依从性的危险因素(OR=2.772,95%CI:1.243~6.183,P=0.013;OR=5.188,95%CI:1.383~19.465,P=0.015; OR=3.363,95%CI:1.645~6.878,P=0.001)。亚组分析显示:文化程度、职业、医保类型和是否了解疗程时间是≤40岁患者戈舍瑞林用药依从性的影响因素(χ2=15.992、5.978、7.701、10.376,P均<0.050);不良反应及医保类型是>40岁患者用药依从性的影响因素(χ2=4.763、7.471,P均<0.050)。Logistic回归分析表明:高中及以下文化程度和不了解疗程时间是≤40岁患者用药依从性的危险因素(OR=5.126,95%CI:2.086~12.598,P<0.001; OR=3.631, 95%CI:1.500~8.792,P=0.004);居民医保是>40岁患者用药依从性的危险因素(OR=64.315,95%CI:2.513~1 646.042,P=0.012),不良反应是>40岁患者用药依从性的保护因素OR=0.189,95%CI=0.047~0.759,P=0.019)。 结论luminal型乳腺癌患者戈舍瑞林用药依从性较差,文化程度、医保类型及是否了解疗程时间都可能影响患者的依从性。≤40岁组和>40岁组患者依从性有差异,且影响因素不同,建议对不同年龄患者用药采用不同的干预措施。  相似文献   
37.
Malignant melanoma is a highly aggressive skin cancer characterized by an elevated grade of tumor cell plasticity. Such plasticity allows adaptation of melanoma cells to different hostile conditions and guarantees tumor survival and disease progression, including aggressive features such as drug resistance. Indeed, almost 50% of melanoma rapidly develop resistance to the BRAFV600E inhibitor vemurafenib, with fast tumor dissemination, a devastating consequence for patients’ outcomes. Vasculogenic mimicry (VM), the ability of cancer cells to organize themselves in perfused vascular-like channels, might sustain tumor spread by providing vemurafenibresistant cancer cells with supplementary ways to enter into circulation and disseminate. Thus, this research aims to determine if vemurafenib resistance goes with the acquisition of VM ability by aggressive melanoma cells, and identify a driving molecule for both vemurafenib resistance and VM. We used two independent experimental models of drug-resistant melanoma cells, the first one represented by a chronic adaptation of melanoma cells to extracellular acidosis, known to drive a particularly aggressive and vemurafenib-resistant phenotype, the second one generated with chronic vemurafenib exposure. By performing in vitro tube formation assay and evaluating the expression levels of the VM markers EphA2 and VE-cadherin by Western blotting and flow cytometer analyses, we demonstrated that vemurafenib-resistant cells obtained by both models are characterized by an increased ability to perform VM. Moreover, by exploiting the CRISPR-Cas9 technique and using the urokinase plasminogen activator receptor (uPAR) inhibitor M25, we identified uPAR as a driver of VM expressed by vemurafenib-resistant melanoma cells. Thus, uPAR targeting may be successfully leveraged as a new complementary therapy to inhibit VM in drug-resistant melanoma patients, to counteract the rapid progression and dissemination of the disease.  相似文献   
38.
社区获得性肺炎(Community Acquired Pneumonia,CAP)是比较常见的院外肺部炎性疾病之一,随着细菌、支原体、衣原体等多种病原体的耐药率的上升,以及病患梯度的范围增加,CAP的发病率呈逐年上升的趋势,死亡率日益增高,导致医疗资源消耗巨大。目前临床上CAP的患者主要依靠经验性治疗。正确选择抗生素、减少病原体的耐药率,优化肺部炎症疾病的医疗方案,提高CAP临床治愈率已经成为临床医生当前面临的一项重大挑战。中药制剂具有广谱抗菌、调节免疫、不易耐药、简便价廉等特点,是解决上述难题的一个很好途径。  相似文献   
39.
Myung Sun Kim MD  Vinay Prasad MD  MPH 《Cancer》2020,126(19):4270-4272
The US Food and Drug Administration granted acalabrutinib approval as the second Bruton tyrosine kinase (BTK) inhibitor to treat patients with chronic lymphocytic leukemia and small lymphocytic lymphoma as monotherapy or in combination with obinutuzumab. This approval was based on 2 phase 3 trials: ELEVATE-TN and ASCEND. There are several concerns with the design of these trials, including suboptimal treatment of patients in the control arm, expansion of the trial population, and lack of data regarding efficacy or tolerability compared with ibrutinib, a first-in-class drug. The Food and Drug Administration approval of acalabrutinib for patients with chronic lymphocytic leukemia and small lymphocytic lymphoma represents concerning drug approval patterns in the United States and a weakness in evidence generation.  相似文献   
40.
The mechanisms of melanoma metastasis have been the subject of extensive research for decades. Improved diagnostic and therapeutic strategies are of increasing importance for the treatment of melanoma due to its high burden of mortality in the advanced stages of the disease. Intercellular communication is a critical event for the progression of cancer. Collective evidence suggests that exosomes, small extracellular membrane vesicles released by the cells, are important facilitators of intercellular communication between the cells and the surrounding environment. Although the emerging field of exosomes is rapidly gaining traction in the scientific community, there is limited knowledge regarding the role of exosomes in melanoma. This review discusses the multifaceted role of melanoma-derived exosomes in promoting the process of metastasis by modulating the invasive and angiogenic capacity of malignant cells. The future implications of exosome research and the therapeutic potential of exosomes are also discussed.  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