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   4585篇
  免费   259篇
  国内免费   23篇
耳鼻咽喉   55篇
儿科学   153篇
妇产科学   49篇
基础医学   619篇
口腔科学   100篇
临床医学   331篇
内科学   1040篇
皮肤病学   217篇
神经病学   292篇
特种医学   118篇
外科学   528篇
综合类   39篇
预防医学   213篇
眼科学   186篇
药学   336篇
  2篇
中国医学   19篇
肿瘤学   570篇
  2024年   14篇
  2023年   57篇
  2022年   90篇
  2021年   147篇
  2020年   70篇
  2019年   100篇
  2018年   163篇
  2017年   117篇
  2016年   117篇
  2015年   109篇
  2014年   165篇
  2013年   175篇
  2012年   329篇
  2011年   319篇
  2010年   219篇
  2009年   174篇
  2008年   255篇
  2007年   277篇
  2006年   294篇
  2005年   248篇
  2004年   238篇
  2003年   231篇
  2002年   223篇
  2001年   64篇
  2000年   75篇
  1999年   82篇
  1998年   42篇
  1997年   39篇
  1996年   30篇
  1995年   30篇
  1994年   23篇
  1993年   14篇
  1992年   32篇
  1991年   36篇
  1990年   26篇
  1989年   36篇
  1988年   33篇
  1987年   29篇
  1986年   25篇
  1985年   29篇
  1984年   14篇
  1983年   13篇
  1982年   13篇
  1981年   4篇
  1980年   6篇
  1979年   7篇
  1974年   2篇
  1968年   6篇
  1967年   4篇
  1966年   7篇
排序方式: 共有4867条查询结果,搜索用时 31 毫秒
71.
72.
73.
74.
Background Because genotype A of hepatitis B virus (HBV) is not indigenous, there have been only few data on infection with it in Japan.Methods We examined clinical and virological features of the 66 Japanese patients who admitted Toranomon Hospital in Tokyo, Japan, between 1976 and 2001, who were found to have HBV/A infection. HBV genotype A was classified into subtype A (European type) and A (South African type) by phylogenetic analysis of the preS1 and preS2 regions, and the S gene sequences.Results Of the 66 patients infected with HBV/A, 14 (21%) were asymptomatic carriers, 26 (39%) presented with acute hepatitis, 22 (33%) with chronic hepatitis, and 4 (6%) with liver cirrhosis. HBV/A infection persisted for more than 6 months in 5 of the 26 (19%) patients with acute hepatitis. The frequency of acute hepatitis in patients infected with HBV/A was higher after than before 1991 (2/22 [9%] vs 24/44 [55%]; P < 0.0001). The frequency of nucleotide 1858 of T was higher in asymptomatic carriers than in patients with acute hepatitis in whom infection was resolved (5/14 [36%] vs 0/21 [0%]; P = 0.008). Of the 57 patients for whom subtypes of genotype A were determined, subtype A was identified in 53 (93%) and subtype A in only 4 (7%). All patients infected with subtype A were persistently infected with HBV.Conclusions HBV/A infection has become more frequent during recent years, predominantly presenting as acute hepatitis, and subtype A is uncommon in the Tokyo metropolitan area.  相似文献   
75.
The Cytochrome P450 is the major enzyme involved in drug metabolism. CYP enzymes are responsible for the metabolism of most clinically used drugs. Individual variability in CYP activity is one important factor that contributes to drug therapy failure. We have developed a new straightforward TaqMan PCR genotyping assay to investigate the prevalence of the most common allelic variants of polymorphic CYP enzymes CYP1A2, CYP2C9, CYP2C19, CYP2D6 and CYP3A5 in the Japanese population. Moreover, we focused on the combination of each genotype for clinical treatment. The genotype analysis identified a total of 139 out of 483 genotype combinations of five genes in the 1,003 Japanese subjects. According to our results, most of subjects seemed to require dose modification during clinical treatment. In the near future, modifications should be considered based on the individual patient genotype of each treatment.  相似文献   
76.

Objective

First degree relatives (FDRs) of someone with colorectal cancer (CRC) are at increased risk of the disease. In this study we examine the factors associated with discussing family history of CRC with a health professional.

Methods

People with CRC, recruited through the population-based Victorian Cancer Registry in Australia, were asked to refer FDRs to the study. Eight hundred and nineteen FDRs completed a telephone interview.

Results

Thirty-six percent of FDRs recalled ever being asked about their family history of bowel cancer by a health professional. Factors associated with having this discussion were being aged 50–60 years, having a university education, being in the potentially high risk category, being very worried about getting bowel cancer and knowing that family history increases risk through discussions with family, friends or their own education.

Conclusion

Despite evidence that doctor endorsement is a key factor in the uptake of CRC screening, our study shows that the majority of FDRs do not recall being asked by a health professional about their family history.

Practice implications

There is a need to identify the most appropriate method to improve rates of health professional discussion of family history with relatives of CRC patients in order to improve screening rates.  相似文献   
77.
78.
79.
A 61-year-old woman with a very rare case of totally ossified large thoracic spinal metaplastic meningioma, showing progressing myelopathy is presented. Computed tomographic images showed a large totally ossfied intradural round mass occupying the spinal canal on T9-10 level. Magnetic resonance imaging revealed a large T9-10 intradural extramedullary mass that was hypointense to spinal cord on T1- and T2-weighted sequences, partial enhancement was apparent after Gadolinium administration. The spinal cord was severely compressed and displaced toward the right at the level of T9-10. Surgical removal of the tumor was successfully accomplished via the posterior midline approach and the histological diagnosis verified an ossified metaplastic meningioma. The clinical neurological symptoms of patient were improved postoperatively. In this article we discuss the surgical and pathological aspects of rare case of spinal totally ossified metaplastic meningioma.  相似文献   
80.
Atypically-shaped cardiomyocytes (ACMs) are a new subpopulation of spontaneously beating heart cells with a peculiar morphology identified within a culture of cardiac myocyte-depleted fraction (CMDF) cells obtained from adult mouse heart. ACMs originate from small cells in CMDF and grow in size and start beating within ~3 days culture without appreciable proliferation or express stem cell marker proteins, but stay in the heart until elderly stages. However, the characteristics of ACMs are largely unclear. The present study examined whether pre-exposure of CMDF cells to severe ischemia abolished the ability of ACMs to develop into beating cells. Of ACMs that underwent ischemia, ~50 % grew in size, changed the morphology, and started beating during the subsequent culture under normoxia. ACMs displayed constitutively active autophagy during the culture. The results suggest the possibility that the development of beating ACMs could occur in injured heart, even if the surviving cell population is small.  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