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   18707篇
  免费   1838篇
  国内免费   360篇
耳鼻咽喉   127篇
儿科学   663篇
妇产科学   307篇
基础医学   3350篇
口腔科学   147篇
临床医学   1300篇
内科学   4054篇
皮肤病学   1113篇
神经病学   309篇
特种医学   449篇
外国民族医学   16篇
外科学   717篇
综合类   1520篇
现状与发展   4篇
预防医学   243篇
眼科学   264篇
药学   704篇
  2篇
中国医学   109篇
肿瘤学   5507篇
  2024年   14篇
  2023年   347篇
  2022年   326篇
  2021年   688篇
  2020年   807篇
  2019年   724篇
  2018年   717篇
  2017年   753篇
  2016年   674篇
  2015年   848篇
  2014年   1138篇
  2013年   1230篇
  2012年   923篇
  2011年   925篇
  2010年   743篇
  2009年   767篇
  2008年   904篇
  2007年   862篇
  2006年   850篇
  2005年   784篇
  2004年   607篇
  2003年   607篇
  2002年   530篇
  2001年   479篇
  2000年   406篇
  1999年   345篇
  1998年   276篇
  1997年   236篇
  1996年   253篇
  1995年   280篇
  1994年   257篇
  1993年   180篇
  1992年   212篇
  1991年   203篇
  1990年   154篇
  1989年   139篇
  1988年   113篇
  1987年   86篇
  1986年   74篇
  1985年   113篇
  1984年   67篇
  1983年   37篇
  1982年   56篇
  1981年   45篇
  1980年   34篇
  1979年   35篇
  1978年   24篇
  1977年   13篇
  1976年   9篇
  1966年   5篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
《Vaccine》2022,40(30):4038-4045
PurposeAs protection from COVID-19 following two doses of the BNT162b2 vaccine showed a time dependent waning, a third (booster) dose was administrated. This study aims to compare the antibody response following the third dose versus the second and to evaluate post-booster seroconversion.MethodsA prospective observational study conducted in Maccabi Healthcare Services. Serial SARS-CoV-2 Spike IgG tests, 1,2,3 and 6 months following the second vaccine dose and one month following the third were obtained. Neutralizing antibody levels were measured in a subset of participants. Per individual SARS-CoV-2 Spike IgG titer ratios were calculated one month after the booster administration compared to titers one month following the second dose and prior to booster.ResultsAmong 110 participants, 56 (51%) were women. Mean age was 61.7 ± 1.9 years and 66 (60%) were immunocompromised. One month after third dose, IgG titers were induced 7.83 (95 %CI 5.25–11.67) folds and 2.40 (95 %CI 1.90–3.03) folds compared to one month after the second, in the immunocompromised and immunocompetent groups, respectively. Of the 17 immunocompromised participants who were seronegative after the second dose, 4 (24%) became seropositive following the third. Comparing the titers prior to the third dose, an increase of 50.7 (95 %CI 32.5–79.1) fold in the immunocompromised group and 25.7 (95 %CI 19.1–34.7) fold in and immunocompetent group, was observed.ConclusionA third BNT162b2 vaccine elicited robust humoral response, superior to the response observed following the second, among immunocompetent and immunocompromised individuals.  相似文献   
2.
3.
4.
BackgroundIn order to avoid excessive treatment of thyroid nodules in the clinic, it is necessary to find a simple and practical analysis method to comprehensively and accurately reflect benign or malignant thyroid nodules. This study aimed to construct and validate a comprehensive and reliable network-based predictive model using a variety of imaging and laboratory criteria for thyroid nodules to stratify the risk of malignancy prior to surgery.MethodsWe retrospectively analyzed data from patients who underwent surgical treatment for thyroid nodules at the Thyroid and Breast Diagnosis and Treatment Center of Weifang Hospital of Traditional Chinese Medicine between January 2018 and December 2020. Binary logical regression analysis was performed to predict whether nodules were malignant or benign. The developmental dataset included 457 patients (January 2018–December 2020). The validation set included separate data points (n = 225, January 2018–December 2020).ResultsIn this study, criteria that showed significant predictive value for malignant nodules included TI-RADS: 4b (p = 0.065); Bethesda IV, Bethesda V, Bethesda VI (P < 0.0001); BRAFV600E mutation (P < 0.0001); Calcitonin>5 pg/ml (p = 0.0037); and FNA-Tg>30 ng/ml (p = 0.0003). A 10-grade risk scoring system was developed. The risk of malignancy risk ranged from 2.06% to 100% and was positively associated with increasing risk grade. The areas under the receiver-operating characteristic curve of the development and validation sets were 0.972 and 0.946, respectively.ConclusionA simple, comprehensive and reliable web-based predictive model was designed using a variety of imaging and laboratory criteria to stratify thyroid nodules by probability of malignancy.  相似文献   
5.
6.
  • Children with cancer receive many medications outside the hospital administered by their caregivers.
  • The study by Walsh et al. shows the number and types of medication errors in these patients. The study includes data from three different centers.
  • Importantly, the study shows the types of errors that cause harm. The authors describe how the harmful errors can be prevented.
  • We suggest ways these results can be used to identify which patients and families will benefit from additional attention. Providing more help at clinic and in the home may help prevent harmful medication errors in children with cancer.
  相似文献   
7.
背景 原发性中枢神经系统淋巴瘤(PCNSL)的预后较差,明确其预后危险因素是改善其预后的关键。生物-心理-社会医学模式提示社会心理因素的重要性。婚姻是重要的社会心理因素之一,但婚姻状态对PNSCL患者预后的影响尚不明确。 目的 探究婚姻状态对PCNSL患者总生存(OS)和癌因生存(CSS)的影响。 方法 于2020年,提取2000—2016年美国"监测、流行病学和结果"数据库的3 993例PCNSL患者的病例资料,包括社会人口学资料(婚姻状态、确诊年龄、种族、性别和确诊年份)、临床病理资料(病理类型、肿瘤位置)、治疗资料(手术、放疗和化疗)及结局资料(生存信息和随访时间)。依据婚姻状态将患者分为已婚和非已婚两组,其中非已婚包括单身、离异和丧偶。采用倾向性评分匹配均衡基线资料,采用Kaplan-Meier分析(Log-rank检验)、Cox回归评估婚姻状态对患者OS和CSS的影响。 结果 倾向性评分匹配后,已婚组和非已婚组患者基线资料比较,差异均无统计学意义(P>0.05)。将患者按婚姻状态分为已婚和非已婚组:Log-rank检验结果显示,与已婚患者相比,非已婚患者的OS和CSS更差(P<0.05);倾向性评分匹配后,校正确诊年龄、种族、性别、确诊年份、病理类型、肿瘤位置、手术、放疗和化疗因素后,多因素Cox回归分析结果显示,非已婚患者的OS风险是已婚患者的1.24倍〔95%CI(1.14,1.36),P<0.001〕,非已婚患者的CSS风险是已婚患者的1.22倍〔95%CI(1.11,1.33),P<0.001〕。将患者按婚姻状态分为已婚、单身、离异、丧偶组:Log-rank检验结果显示,与已婚患者相比,丧偶患者的OS和CSS预后更差(P<0.05);校正确诊年龄、种族、性别、确诊年份、病理类型、肿瘤位置、手术、放疗和化疗因素后,多因素Cox回归结果显示,单身患者OS和CSS风险分别是已婚患者的1.14倍〔95%CI(1.03,1.27),P=0.013〕和1.15倍〔95%CI(1.03,1.29),P=0.012〕,离异患者OS和CSS风险分别是已婚患者的1.23倍〔95%CI(1.07,1.41),P=0.004〕和1.22倍〔95%CI(1.05,1.41),P=0.009〕,丧偶患者OS和CSS风险分别是已婚患者的1.37倍〔95%CI(1.21,1.54),P<0.001〕和1.28倍〔95%CI(1.12,1.46),P=0.013〕。 结论 婚姻状态影响PCNSL患者OS和CSS,与已婚相比,单身、离异和丧偶患者的预后更差,这提示在临床管理和决策中,除了传统的肿瘤生物学特征,还应关注婚姻状态对PCNSL患者预后的影响。  相似文献   
8.
Myelofibrosis is a heterogeneous myeloproliferative neoplasm characterized by chronic inflammation, progressive bone marrow failure, and hepatosplenic extramedullary hematopoiesis. Treatments like Janus kinase inhibitor monotherapy (e.g., ruxolitinib) provide significant spleen and symptom relief but demonstrate limited ability to lead to a durable disease modification. There is an urgent unmet medical need for treatments with a novel mechanism of action that can modify the underlying pathophysiology and affect the disease course of myelofibrosis. This review highlights the role of B-cell lymphoma (BCL) protein BCL-extra large (BCL-XL) in disease pathogenesis and the potential role that navitoclax, a BCL-extra large/BCL-2 inhibitor, may have in myelofibrosis treatment.  相似文献   
9.
10.
《Drug discovery today》2022,27(1):246-256
Bromodomain-containing protein 4 (BRD4) is emerging as a therapeutic target that acts synergistically with other targets of small-molecule drugs in cancer. Therefore, the discovery of potential new dual-target inhibitors of BRD4 may be a promising strategy for cancer therapy. In this review, we highlight a series of strategies to design therapeutic dual-target inhibitors of BRD4 that focus on the synergistic functions of this protein. Drug combinations that exploit synthetic lethality, protein–protein interactions, functional complementarity, and blocking of resistance mechanisms could ultimately overcome the barriers inherent to the development of BRD4 inhibitors as future cancer drugs.  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