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   16907篇
  免费   1126篇
  国内免费   70篇
耳鼻咽喉   152篇
儿科学   425篇
妇产科学   572篇
基础医学   2465篇
口腔科学   519篇
临床医学   1538篇
内科学   3338篇
皮肤病学   639篇
神经病学   1569篇
特种医学   1157篇
外科学   2475篇
综合类   120篇
一般理论   12篇
预防医学   691篇
眼科学   358篇
药学   962篇
中国医学   13篇
肿瘤学   1098篇
  2023年   162篇
  2022年   145篇
  2021年   580篇
  2020年   342篇
  2019年   522篇
  2018年   583篇
  2017年   452篇
  2016年   498篇
  2015年   575篇
  2014年   699篇
  2013年   856篇
  2012年   1226篇
  2011年   1187篇
  2010年   701篇
  2009年   660篇
  2008年   926篇
  2007年   863篇
  2006年   805篇
  2005年   735篇
  2004年   717篇
  2003年   624篇
  2002年   550篇
  2001年   224篇
  2000年   201篇
  1999年   181篇
  1998年   124篇
  1997年   84篇
  1996年   59篇
  1995年   68篇
  1994年   62篇
  1993年   58篇
  1992年   85篇
  1991年   90篇
  1990年   74篇
  1989年   77篇
  1988年   79篇
  1987年   85篇
  1986年   73篇
  1985年   84篇
  1984年   61篇
  1983年   43篇
  1981年   39篇
  1979年   61篇
  1977年   41篇
  1975年   41篇
  1974年   37篇
  1973年   37篇
  1971年   43篇
  1928年   42篇
  1913年   43篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
1.
Journal of Public Health - Group prenatal care provides an alternative model of prenatal care that allows for collaboration with peers, education, discussion, and self-management training in...  相似文献   
2.
3.
European Surgery - The beneficial outcomes of hepatectomy in patients with colorectal metastases have encouraged the attempts of repeated hepatectomy in patients with recurrent disease. Although...  相似文献   
4.
5.
The Dutch Drug Rediscovery Protocol (DRUP) and the Australian Cancer Molecular Screening and Therapeutic (MoST) Program are similar nonrandomized, multidrug, pan-cancer trial platforms that aim to identify signals of clinical activity of molecularly matched targeted therapies or immunotherapies outside their approved indications. Here, we report results for advanced or metastatic cancer patients with tumors harboring cyclin D-CDK4/6 pathway alterations treated with CDK4/6 inhibitors palbociclib or ribociclib. We included adult patients that had therapy-refractory solid malignancies with the following alterations: amplifications of CDK4, CDK6, CCND1, CCND2 or CCND3, or complete loss of CDKN2A or SMARCA4. Within MoST, all patients were treated with palbociclib, whereas in DRUP, palbociclib and ribociclib were assigned to different cohorts (defined by tumor type and alteration). The primary endpoint for this combined analysis was clinical benefit, defined as confirmed objective response or stable disease ≥16 weeks. We treated 139 patients with a broad variety of tumor types; 116 with palbociclib and 23 with ribociclib. In 112 evaluable patients, the objective response rate was 0% and clinical benefit rate at 16 weeks was 15%. Median progression-free survival was 4 months (95% CI: 3-5 months), and median overall survival 5 months (95% CI: 4-6 months). In conclusion, only limited clinical activity of palbociclib and ribociclib monotherapy in patients with pretreated cancers harboring cyclin D-CDK4/6 pathway alterations was observed. Our findings indicate that monotherapy use of palbociclib or ribociclib is not recommended and that merging data of two similar precision oncology trials is feasible.  相似文献   
6.
7.
Accurate modeling of intratumor heterogeneity presents a bottleneck against drug testing. Flexibility in a preclinical platform is also desirable to support assessment of different endpoints. We established the model system, OHC-NB1, from a bone marrow metastasis from a patient diagnosed with MYCN-amplified neuroblastoma and performed whole-exome sequencing on the source metastasis and the different models and passages during model development (monolayer cell line, 3D spheroid culture and subcutaneous xenograft tumors propagated in mice). OHC-NB1 harbors a MYCN amplification in double minutes, 1p deletion, 17q gain and diploid karyotype, which persisted in all models. A total of 80–540 single-nucleotide variants (SNVs) was detected in each sample, and comparisons between the source metastasis and models identified 34 of 80 somatic SNVs to be propagated in the models. Clonal reconstruction using the combined copy number and SNV data revealed marked clonal heterogeneity in the originating metastasis, with four clones being reflected in the model systems. The set of OHC-NB1 models represents 43% of somatic SNVs and 23% of the cellularity in the originating metastasis with varying clonal compositions, indicating that heterogeneity is partially preserved in our model system.  相似文献   
8.
Abstract

Introduction: Curriculum mapping shows concordances and differences between the intended and the taught curriculum. To our knowledge, no previous studies describe the effects that this mapping has on the curriculum. The aim of the present study is to map the content of a lecture series in surgery to the National Catalogue of Learning Objectives in Surgery and analyze the effects this mapping has on the content of the following lecture series.

Methods: All lecturers in the lecture series were directly observed by a minimum of two reviewers and learning objectives and the level of competence were documented. After the lecture series, the results were visualized within the catalog of learning objectives and were sent to the lecturers. In the following lecture series, learning objectives were documented correspondingly.

Results: In the first lecture series, 47% of the learning objectives were taught. After the mapping, the number of learning objectives that were taught increased to 59% (p?<?0.001). The increase was found in all surgical disciplines and in all levels of competences without any changes in the average duration of the lectures.

Conclusions: The presented method for mapping a curriculum effectively increased the number of taught learning objectives without requiring longer lecture durations.  相似文献   
9.
This study explores the forces that drive the formation of physician patient sharing networks. In particular, I examine the degree to which hospital affiliation drives physicians' sharing of Medicare patients. Using a revealed preference framework where observed network links are taken to be pairwise stable, I estimate the physicians' pair‐specific values using a tetrad maximum score estimator that is robust to the presence of unobserved physician specific characteristics. I also control for a number of potentially confounding patient sharing channels, such as (a) common physician group or hospital system affiliation, (b) physician homophily, (c) knowledge complementarity, (d) patient side considerations related to both geographic proximity and insurance network participation, and (e) spillover from other collaborations. Focusing on the Chicago hospital referral region, I find that shared hospital affiliation accounts for 36.5% of the average pair‐specific utility from a link. Implications for reducing care fragmentation are discussed.  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