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   2144767篇
  免费   151019篇
  国内免费   3972篇
耳鼻咽喉   31514篇
儿科学   68013篇
妇产科学   60446篇
基础医学   303181篇
口腔科学   62933篇
临床医学   187919篇
内科学   409781篇
皮肤病学   48777篇
神经病学   168380篇
特种医学   84344篇
外国民族医学   595篇
外科学   327422篇
综合类   48588篇
现状与发展   7篇
一般理论   677篇
预防医学   153202篇
眼科学   51402篇
药学   165685篇
  10篇
中国医学   5061篇
肿瘤学   121821篇
  2018年   20751篇
  2016年   18583篇
  2015年   20729篇
  2014年   28815篇
  2013年   43154篇
  2012年   57633篇
  2011年   61079篇
  2010年   36097篇
  2009年   34421篇
  2008年   57525篇
  2007年   62315篇
  2006年   63141篇
  2005年   60576篇
  2004年   58587篇
  2003年   56414篇
  2002年   55064篇
  2001年   104509篇
  2000年   107292篇
  1999年   90253篇
  1998年   24076篇
  1997年   21636篇
  1996年   21141篇
  1995年   19871篇
  1994年   18441篇
  1993年   17345篇
  1992年   69485篇
  1991年   67134篇
  1990年   65984篇
  1989年   64035篇
  1988年   59050篇
  1987年   57914篇
  1986年   55217篇
  1985年   52332篇
  1984年   38914篇
  1983年   33056篇
  1982年   19304篇
  1981年   17403篇
  1979年   36698篇
  1978年   25786篇
  1977年   22628篇
  1976年   20325篇
  1975年   23065篇
  1974年   27240篇
  1973年   26566篇
  1972年   25289篇
  1971年   23678篇
  1970年   22196篇
  1969年   21354篇
  1968年   19697篇
  1967年   17648篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
21.
Colorectal cancer (CRC) is the third most diagnosed cancer and the second leading cause of cancer-related mortality in the United States. Across the globe, people in the age group older than 50 are at a higher risk of CRC. Genetic and environmental risk factors play a significant role in the development of CRC. If detected early, CRC is preventable and treatable. Currently, available screening methods and therapies for CRC treatment reduce the incidence rate among the population, but the micrometastasis of cancer may lead to recurrence. Therefore, the challenge is to develop an alternative therapy to overcome this complication. Nanotechnology plays a vital role in cancer treatment and offers targeted chemotherapies directly and selectively to cancer cells, with enhanced therapeutic efficacy. Additionally, nanotechnology elevates the chances of patient survival in comparison to traditional chemotherapies. The potential of nanoparticles includes that they may be used simultaneously for diagnosis and treatment. These exciting properties of nanoparticles have enticed researchers worldwide to unveil their use in early CRC detection and as effective treatment. This review discusses contemporary methods of CRC screening and therapies for CRC treatment, while the primary focus is on the theranostic approach of nanotechnology in CRC treatment and its prospects. In addition, this review aims to provide knowledge on the advancement of nanotechnology in CRC and as a starting point for researchers to think about new therapeutic approaches using nanotechnology.  相似文献   
22.
Maternal and Child Health Journal - Early life exposures can have an impact on a child’s developmental trajectory and children born late preterm (34–36 weeks gestational age)...  相似文献   
23.
24.
ABSTRACT

Objective: Dry eye is reported to be associated with several neurological diseases. The aim of this study is to evaluate the patients with hemiplegia after stroke for dry eye and compare their results with a control group.

Materials and methods: Forty-five patients with hemiplegia and 45 individuals as the control group were included in the study. Tear function tests (Schirmer and tear breakup time) and a dry eye questionnaire for dry eye symptoms (ocular surface disease index) were performed and the results of the two groups were compared.

Results: Schirmer test results were significantly lower in the post-stroke hemiplegia group compared to the control group (11.3 ± 8.2 mm and 20.6 ± 11.6 mm, respectively, p < .001). Tear breakup time results were significantly lower in the post-stroke hemiplegia group compared to the control group (7.9 ± 3.1 s and 12.1 ± 4.3 s, respectively, p < .001). Ocular surface disease index scores were not significantly different between hemiplegia and control groups (21.6 ± 20.0 and 19.8 ± 13.9, respectively, p = .635). Schirmer scores lower than 10 mm (60% and 30%, p < .001) and tear breakup time results lower than 10 s (65.6% and 28.9%, p < .001) were also higher in the hemiplegia group compared to control group.

Conclusion: We found lower Schirmer test and tear breakup time results and similar OSDI scores in hemiplegia patients compared to controls. Hemiplegia patients may have dry eye without typical symptoms. This should be taken into consideration in the follow-up and rehabilitation of post-stroke hemiplegia patients.  相似文献   
25.
Introduction: Percutaneous renal mass biopsy has evolved over the last decade with improvements on previous pitfalls including low tissue yield, high non-diagnostic rates, and complications. As understanding of tumor biology and natural history of renal cortical neoplasms has improved, percutaneous renal mass biopsy is poised to have an expanding role in an area characterized by individualized management and refined risk stratification.

Areas covered: This review summarizes the evolution of renal mass biopsy to its current state with respect to outcomes, indications, and clinical guidelines.

Expert opinion: With improved understanding of differential biological potential of renal cortical neoplasms combined with technical improvements in diagnostic yield and accuracy, utilization of renal mass biopsy is becoming an important adjunct to patient care in a broad range of clinical scenarios, including active surveillance, thermal ablation, and use of primary systemic therapy in localized and advanced settings.  相似文献   

26.
27.
28.
29.
30.
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