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   483891篇
  免费   45189篇
  国内免费   14294篇
耳鼻咽喉   4693篇
儿科学   10806篇
妇产科学   9036篇
基础医学   36248篇
口腔科学   8333篇
临床医学   56424篇
内科学   65217篇
皮肤病学   4668篇
神经病学   17532篇
特种医学   19892篇
外国民族医学   274篇
外科学   69434篇
综合类   51249篇
现状与发展   64篇
一般理论   8篇
预防医学   33067篇
眼科学   4950篇
药学   43859篇
  297篇
中国医学   13097篇
肿瘤学   94226篇
  2024年   570篇
  2023年   7383篇
  2022年   11184篇
  2021年   23459篇
  2020年   18879篇
  2019年   22744篇
  2018年   17331篇
  2017年   17059篇
  2016年   19427篇
  2015年   23477篇
  2014年   39272篇
  2013年   37581篇
  2012年   35918篇
  2011年   33365篇
  2010年   27506篇
  2009年   27109篇
  2008年   26097篇
  2007年   25111篇
  2006年   21683篇
  2005年   15915篇
  2004年   10886篇
  2003年   9299篇
  2002年   7751篇
  2001年   6673篇
  2000年   5655篇
  1999年   4446篇
  1998年   4356篇
  1997年   3962篇
  1996年   2937篇
  1995年   3112篇
  1994年   2763篇
  1993年   2185篇
  1992年   2250篇
  1991年   1990篇
  1990年   1828篇
  1989年   1747篇
  1988年   1567篇
  1987年   1411篇
  1986年   1170篇
  1985年   2196篇
  1984年   2236篇
  1983年   1598篇
  1982年   1709篇
  1981年   1659篇
  1980年   1427篇
  1979年   1164篇
  1978年   888篇
  1977年   859篇
  1976年   775篇
  1975年   496篇
排序方式: 共有10000条查询结果,搜索用时 649 毫秒
1.
《Cancer radiothérapie》2022,26(4):611-615
In order to provide more convenient irradiation regimens for patient comfort, radiation facility organization and health expenses, new hypofractionated protocols have been evaluated. Moderately (dose/fraction: 2.3 to 3 Gy), then ultra (dose/fraction: 5.2 to 6.1 Gy) hypofractionated irradiations were first validated. The current question is: is it possible to go forward using extreme hypofractionated regimens (EHR) based on 1 to 3 fractions. Different irradiation techniques are under investigation. However, brachytherapy remains the smartest way to deliver a high dose in a small volume. We report prospective and retrospective study results which evaluated EHR for breast and prostate brachytherapy. While oncological outcome and toxicity profile appear extremely encouraging for low-risk breast cancer after a 1 to 4 fractions (6.25 to 20 Gy/fraction), the use of a single fraction of 19 to 23 Gy appears debatable for prostate cancer. Brachytherapy represents an emblematic example of EHR but longer follow-up and more mature results are awaited in order to specify the right indications and refine the EQD2 calculation method including new biological and technical factors.  相似文献   
2.
乳腺癌是全球女性发病率最高的恶性肿瘤,随着诊断技术及治疗手段的不断提高,乳腺癌患者接受系统治疗后生存期明显延长。乳腺癌患者需要长时间的随访以便及早监测到局部复发和远处转移。此外,激素敏感性乳腺癌患者还需要给予5~10年的内分泌治疗,针对其副作用的全程管理也需要随访,进而提高患者的生活质量,减轻患者疾病负担。本文就近年来乳腺癌随访相关方面进行简要综述。  相似文献   
3.
《Vaccine》2022,40(52):7604-7612
Background and ObjectiveVaccine uptake during pregnancy remains low. Our objectives were to describe 1) development and adaptation of a clinician communication training intervention for maternal immunizations and 2) obstetrics and gynecology (ob-gyn) clinician and staff perspectives on the intervention and fit for the prenatal care context.MethodsDesign of the Motivational Interviewing for Maternal Immunizations (MI4MI) intervention was based on similar communication training interventions for pediatric settings and included presumptive initiation of vaccine recommendations (“You’re due for two vaccines today”) combined with motivational interviewing (MI) for hesitant patients. Interviews and focus group discussions were conducted with ob-gyn clinicians and staff in five Colorado clinics including settings with obstetric physicians, certified nurse midwives (CNMs), and clinician-trainees. Participants were asked about adapting training to the ob-gyn setting and their implementation experiences. Feedback was incorporated through iterative changes to training components.ResultsInterview and focus group discussion results from participants before (n = 3), during (n = 11) and after (n = 25) implementation guided intervention development and adaptation. Three virtual, asynchronous training components were created: a video and two interactive modules. This virtual format was favored due to challenges attending group meetings; however, participants noted opportunities to practice skills through role-play were lacking. Training modules were adapted to include common challenging vaccine conversations and live-action videos. Participants liked interactive training components and use of adult learning strategies. Some participants initially resisted the presumptive approach but later found it useful after applying it in their practices. Overall, participants reported that MI4MI training fit well with the prenatal context and recommended more inclusion of non-clinician staff.ConclusionsMI4MI training was viewed as relevant and useful for ob-gyn clinicians and staff. Suggestions included making training more interactive, and including more complex scenarios and non-clinician staff.  相似文献   
4.
5.
This meta-analysis was designed to assess the effectiveness and safety of extracorporeal shock wave therapy (ESWT) for patients with low back pain (LBP). Pubmed, Embase, Cochrane's library, PEDro (Physiotherapy Evidence Database), China National Knowledge Infrastructure (CNKI), and Wanfang Data were searched until December 2019 to identify studies assessing the effectiveness and safety of EPSW for LBP. The prime outcome is pain intensity measured by Visual Analog Scale (VAS) or numeric rating scale (NRS). Other outcomes included functional status, quality of life, psychological outcomes measured by Oswestry Disability Index (ODI), as well as the adverse events. Mean differences (MD) were calculated for continuous outcomes, while odd ratios (OR) were calculated for binary outcomes. Revman 5.3 software was used for statistical analysis. Five randomized controlled trials (RCTs) were finally included in this meta-analysis. The pooled mean difference in post-treatment pain scores was −2.37 (P <0.0001), indicating that post-treatment pain scores was significantly higher by 2.37 in control group than in ESWT group. At a mean follow-up time of 4–6 weeks, the pooled mean difference in ODI scores was −14.10 (P <0.00001), indicating that the pooled mean difference of post-treatment ODI scores was 14.10 higher in control group than in ESWT group. The use of ESWT is effective in alleviating pain and improving the general functional state for patients with LBP. However, more evidence was needed to verify its safety.  相似文献   
6.
目的 观察结肠癌HCT116细胞健脾消癌方的条件培养液对HUVEC细胞管腔形成的影响,从PI3K/Akt生物轴调控角度探讨其作用机制。方法 培养HCT116细胞,细胞设3组:对照组,健脾消癌方组(加入15%健脾消癌方含药血清)及人参皂苷Rg3组;制备HCT116细胞健脾消癌方条件培养液(分组及制备方法见实验方法),用条件培养液干预HUVEC(脐静脉内皮细胞,Human Umbilical Vein Endothelial Cells),Matrigel基质胶法检测HCT116细胞健脾消癌方条件培养液对HUVEC小管形成的影响。随后采用蛋白免疫印迹法(Western blot)检测各组HCT116细胞磷脂酰肌醇3-激酶(PI3K)、蛋白激酶B(Akt)、p-Akt、VEGF(血管内皮生长因子,Vascular endothelial growth factor)蛋白表达。最后在结肠癌HCT116荷瘤小鼠中验证健脾消癌方对肿瘤生长速度的影响,并经瘤组织VEGF蛋白表达、CD31免疫组化染色检测肿瘤内血管生成情况。结果 模型组HUVEC细胞管腔形成较空白血清组显著增加(P<0.05);健脾消癌方组及人参皂苷Rg3组较模型组HUVEC细胞管腔形成显著减少(P<0.01)。p-Akt和VEGF蛋白表达水平模型组高于空白血清组(P<0.05),健脾消癌方组及人参皂苷Rg3组显著低于模型组(P<0.01);PI3K、Akt蛋白表达量组间差异无统计学意义。与对照组比较,模型组荷瘤小鼠肿瘤体积显著性增大,瘤组织内VEGF表达、CD31阳性面积显著性增加,差异有统计学意义(P<0.05);与模型组比较,健脾消癌方组及人参皂苷Rg3组荷瘤小鼠肿瘤体积显著减小,瘤组织内VEGF表达、CD31阳性面积降低,差异有统计学意义(P<0.05)。结论 健脾消癌方可抑制肿瘤的血管生成和生长,其作用机制可能与PI3K/Akt生物轴调控VEGF表达有关。  相似文献   
7.
Background: Breast cancer (BC) is the most common malignant tumor in women, and its morbidity and mortality are increasing each year, due to the lack of specific clinical symptoms in the early stage of BC, and the lack of diagnostic methods for early breast cancer. Therefore, identifying an effective diagnostic method for early BC has become urgent. Materials and Methods: Breast lesions with a histological diagnosis that were examined by ultrasonic elastography (UE) in our department from June 2020 to December 2021 were reviewed. qRT-PCR was performed to measure the expression levels of miR-144-5p and miR-26b-5p in the plasma of patients with BC. The receiver operating characteristics (ROC) curve and area under the curve (AUC) were used to investigate the potential diagnostic value of miR- 144-5p, miR-26b-5p and the elastographic score in BC. Results: The ultrasonic elastography score(UES) was found to be significantly upregulated in BC compared with that in benign breast lesions, and the AUC, sensitivity and specificity were 0.809, 0.717 and 0.806 for distinguishing BC from benign breast lesions, respectively. miR-144-5p and miR-26b- 5p were found to be upregulated in the plasma of BC patients, and miR-144-5p+miR-26b-5p had 0.781 sensitivity and 0.780 specificity for the diagnosis of BC. Furthermore, we found that the diagnostic performance of miR-144-5p and miR-26b-5p combined with UES for BC had 0.913 sensitivity and 0.890 specificity. Conclusions: The combination of plasma miR-144-5p, miR-26b-5p and UES has a very high clinical application value for the early detection of BC.  相似文献   
8.
《Cancer cell》2022,40(3):318-334.e9
  1. Download : Download high-res image (268KB)
  2. Download : Download full-size image
  相似文献   
9.
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