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   209603篇
  免费   50283篇
  国内免费   355篇
耳鼻咽喉   3293篇
儿科学   8502篇
妇产科学   4213篇
基础医学   33585篇
口腔科学   8641篇
临床医学   22774篇
内科学   53900篇
皮肤病学   11269篇
神经病学   24595篇
特种医学   6040篇
外国民族医学   32篇
外科学   32092篇
综合类   752篇
一般理论   67篇
预防医学   16359篇
眼科学   3653篇
药学   14805篇
中国医学   1369篇
肿瘤学   14300篇
  2023年   950篇
  2022年   578篇
  2021年   4123篇
  2020年   6775篇
  2019年   13474篇
  2018年   13673篇
  2017年   13802篇
  2016年   14530篇
  2015年   14337篇
  2014年   15354篇
  2013年   17877篇
  2012年   12841篇
  2011年   13152篇
  2010年   13478篇
  2009年   9423篇
  2008年   9674篇
  2007年   8807篇
  2006年   8572篇
  2005年   8264篇
  2004年   7651篇
  2003年   7154篇
  2002年   6973篇
  2001年   4874篇
  2000年   4984篇
  1999年   3646篇
  1998年   1080篇
  1997年   817篇
  1996年   723篇
  1995年   738篇
  1994年   613篇
  1993年   570篇
  1992年   1605篇
  1991年   1576篇
  1990年   1424篇
  1989年   1270篇
  1988年   1187篇
  1987年   1145篇
  1986年   1076篇
  1985年   1080篇
  1984年   814篇
  1983年   707篇
  1982年   500篇
  1979年   709篇
  1978年   472篇
  1975年   455篇
  1974年   500篇
  1973年   530篇
  1972年   452篇
  1971年   428篇
  1970年   437篇
排序方式: 共有10000条查询结果,搜索用时 62 毫秒
1.
Cyclotron-produced copper-64 radioisotope tracers offer the possibility to perform both diagnostic investigation by positron emission tomography (PET) and radiotherapy by a theranostic approach with bifunctional chelators. The versatile chemical properties of copper add to the importance of this isotope in medicinal investigation. [64Cu][Cu (ATSM)] has shown to be a viable candidate for imaging of tumor hypoxia; a critical tumor microenvironment characteristic that typically signifies tumor progression and resistance to chemo-radiotherapy. Various production and radiosynthesis methods of [64Cu][Cu (ATSM)] exist in labs, but usually involved non-standardized equipment with varying production qualities and may not be easily implemented in wider hospital settings. [64Cu][Cu (ATSM)] was synthesized on a modified GE TRACERlab FXN automated synthesis module. End-of-synthesis (EOS) molar activity of [64Cu][Cu (ATSM)] was 2.2–5.5 Ci/μmol (HPLC), 2.2–2.6 Ci/μmol (ATSM-titration), and 3.0–4.4 Ci/μmol (ICP-MS). Radiochemical purity was determined to be >99% based on radio-HPLC. The final product maintained radiochemical purity after 20 h. We demonstrated a simple and feasible process development and quality control protocols for automated cyclotron production and synthesis of [64Cu][Cu (ATSM)] based on commercially distributed standardized synthesis modules suitable for PET imaging and theranostic studies.  相似文献   
2.
3.
Journal of Immigrant and Minority Health - COVID-19 has disproportionally affected underrepresented minorities (URM) and low-income immigrants in the United States. The aim of the study is to...  相似文献   
4.
5.
6.
Human papillomavirus (HPV) vaccine effectiveness may differ between settings. Here we present the first real-world effectiveness study of HPV vaccination on high-grade cervical lesions from Norway, among women who received HPV vaccine outside the routine program. We performed an observational study of all Norwegian women born 1975 to 1996 and retrieved individual data from nationwide registries on HPV vaccination status and incidence of histologically verified high-grade cervical neoplasia during 2006 to 2016. We estimated the incidence rate ratio (IRR) and 95% confidence intervals (CI) for vaccination vs no vaccination by Poisson regression stratified by age at vaccination <20 years and ≥20 years. The cohort consisted of 832 732 women, of which 46 381 (5.6%) received at least one dose of HPV vaccine by the end of 2016. The incidence rate of cervical intraepithelial neoplasia grade 2 or worse (CIN2+) increased with age regardless of vaccination status and was highest at age 25 to 29, at 637/100 000 among unvaccinated women, 487/100 000 among women vaccinated before age 20 and 831/100 000 among women vaccinated at age 20 or older. The adjusted IRR of CIN2+ between vaccinated and unvaccinated women was 0.62 (95% CI: 0.46-0.84) for women vaccinated below age 20, and 1.22 (95% CI: 1.03-1.43) for women vaccinated at age 20 or older. These findings indicate that HPV vaccination among women too old to be eligible for routine HPV vaccination is effective among women who are vaccinated below age 20 but may not have the desired impact among women who are vaccinated at age 20 or older.  相似文献   
7.
8.
9.
Molnár  B.  Aroca  S.  Dobos  A.  Orbán  K.  Szabó  J.  Windisch  P.  Stähli  A.  Sculean  A. 《Clinical oral investigations》2022,26(12):7135-7142
Clinical Oral Investigations - To evaluate t he long-term outcomes following treatment of RT 1 multiple adjacent gingival recessions (MAGR) using the modified coronally advanced tunnel (MCAT) with...  相似文献   
10.
Genome-scale screening experiments in cancer produce long lists of candidate genes that require extensive interpretation for biological insight and prioritization for follow-up studies. Interrogation of gene lists frequently represents a significant and time-consuming undertaking, in which experimental biologists typically combine results from a variety of bioinformatics resources in an attempt to portray and understand cancer relevance. As a means to simplify and strengthen the support for this endeavor, we have developed oncoEnrichR, a flexible bioinformatics tool that allows cancer researchers to comprehensively interrogate a given gene list along multiple facets of cancer relevance. oncoEnrichR differs from general gene set analysis frameworks through the integration of an extensive set of prior knowledge specifically relevant for cancer, including ranked gene-tumor type associations, literature-supported proto-oncogene and tumor suppressor gene annotations, target druggability data, regulatory interactions, synthetic lethality predictions, as well as prognostic associations, gene aberrations and co-expression patterns across tumor types. The software produces a structured and user-friendly analysis report as its main output, where versions of all underlying data resources are explicitly logged, the latter being a critical component for reproducible science. We demonstrate the usefulness of oncoEnrichR through interrogation of two candidate lists from proteomic and CRISPR screens. oncoEnrichR is freely available as a web-based service hosted by the Galaxy platform ( https://oncotools.elixir.no ), and can also be accessed as a stand-alone R package ( https://github.com/sigven/oncoEnrichR ).  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