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   4125049篇
  免费   342715篇
  国内免费   14368篇
耳鼻咽喉   58790篇
儿科学   134309篇
妇产科学   110463篇
基础医学   633331篇
口腔科学   115006篇
临床医学   368831篇
内科学   736624篇
皮肤病学   103140篇
神经病学   345371篇
特种医学   166771篇
外国民族医学   641篇
外科学   640866篇
综合类   121963篇
一般理论   2450篇
预防医学   344591篇
眼科学   97092篇
药学   292740篇
  20篇
中国医学   10768篇
肿瘤学   198365篇
  2021年   43894篇
  2019年   57773篇
  2018年   72251篇
  2017年   54940篇
  2016年   60606篇
  2015年   74398篇
  2014年   109313篇
  2013年   175119篇
  2012年   112214篇
  2011年   115827篇
  2010年   122684篇
  2009年   125191篇
  2008年   102634篇
  2007年   109425篇
  2006年   118583篇
  2005年   114251篇
  2004年   115717篇
  2003年   106204篇
  2002年   95522篇
  2001年   147822篇
  2000年   142471篇
  1999年   131567篇
  1998年   64824篇
  1997年   61070篇
  1996年   59259篇
  1995年   60194篇
  1994年   54487篇
  1993年   50527篇
  1992年   99082篇
  1991年   96022篇
  1990年   92374篇
  1989年   89768篇
  1988年   83644篇
  1987年   81730篇
  1986年   77806篇
  1985年   76668篇
  1984年   64683篇
  1983年   57679篇
  1982年   47197篇
  1981年   43858篇
  1980年   41220篇
  1979年   56336篇
  1978年   45780篇
  1977年   40568篇
  1976年   37589篇
  1975年   37840篇
  1974年   41478篇
  1973年   39895篇
  1972年   37510篇
  1971年   34495篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
American Indian and Alaska Native (AIAN) individuals are diverse culturally and geographically but share a high prevalence of chronic illness, largely because of obstacles to high-quality health care. The authors comprehensively examined cancer incidence and mortality among non-Hispanic AIAN individuals, compared with non-Hispanic White individuals for context, using population-based data from the National Cancer Institute, the Centers for Disease Control and Prevention, and the North American Association of Central Cancer Registries. Overall cancer rates among AIAN individuals were 2% higher than among White individuals for incidence (2014 through 2018, confined to Purchased/Referred Care Delivery Area counties to reduce racial misclassification) but 18% higher for mortality (2015 through 2019). However, disparities varied widely by cancer type and geographic region. For example, breast and prostate cancer mortality rates are 8% and 31% higher, respectively, in AIAN individuals than in White individuals despite lower incidence and the availability of early detection tests for these cancers. The burden among AIAN individuals is highest for infection-related cancers (liver, stomach, and cervix), for kidney cancer, and for colorectal cancer among indigenous Alaskans (91.3 vs. 35.5 cases per 100,000 for White Alaskans), who have the highest rates in the world. Steep increases for early onset colorectal cancer, from 18.8 cases per 100,000 Native Alaskans aged 20–49 years during 1998 through 2002 to 34.8 cases per 100,000 during 2014 through 2018, exacerbated this disparity. Death rates for infection-related cancers (liver, stomach, and cervix), as well as kidney cancer, were approximately two-fold higher among AIAN individuals compared with White individuals. These findings highlight the need for more effective strategies to reduce the prevalence of chronic oncogenic infections and improve access to high-quality cancer screening and treatment for AIAN individuals. Mitigating the disparate burden will require expanded financial support of tribal health care as well as increased collaboration and engagement with this marginalized population.  相似文献   
2.
The analysis of mismatch repair proteins in solid tissue is the standard of care (SoC) for the microsatellite instability (MSI) characterization in endometrial cancer (EC). Uterine aspirates (UAs) or circulating-DNA (cfDNA) samples capture the intratumor heterogeneity and provide a more comprehensive and dynamic molecular diagnosis. Thus, MSI analysis by droplet-digital PCR (ddPCR) in UAs and cfDNA can provide a reliable tool to characterize and follow-up the disease. The UAs, paraffin-embedded tumor tissue (FFPE) and longitudinal plasma samples from a cohort of 90 EC patients were analyzed using ddPCR panel and compared to the SoC. A high concordance (96.67%) was obtained between the analysis of MSI markers in UAs and the SoC. Three discordant cases were validated as unstable by ddPCR on FFPE samples. Besides, a good overall concordance (70.27%) was obtained when comparing the performance of the ddPCR assay on UAs and cfDNA in high-risk tumors. Importantly, our results also evidenced the value of MSI analysis to monitor the disease evolution. MSI evaluation in minimally invasive samples shows great accuracy and sensitivity and provides a valuable tool for the molecular characterization and follow-up of endometrial tumors, opening new opportunities for personalized management of EC.  相似文献   
3.
4.
5.
AIDS and Behavior - Although misperceived norms often drive personal health behaviors, we do not know about this phenomenon in the context of antiretroviral therapy (ART) adherence. We conducted a...  相似文献   
6.
Spindler  L.  Alam  A.  Fathallah  N.  Rentien  A.-L.  Draullette  M.  Pommaret  E.  Thierry  M.-L.  Mituialy  A. El  Abbes  L.  Aubert  M.  Benfredj  P.  Far  E. Safa  Beaussier  H.  de Parades  V. 《Techniques in coloproctology》2022,26(2):143-146
Techniques in Coloproctology - The aim of our study was to assess the efficacy of sinus laser therapy (SiLaT) for the treatment of pilonidal disease. All adult patients treated with SiLaT in our...  相似文献   
7.
Clinical Rheumatology - This study aimed to assess treatment patterns and frequency of inadequate response associated with advanced therapy initiation among patients with ankylosing spondylitis...  相似文献   
8.
The International Journal of Cardiovascular Imaging - This study investigated the impact of bicuspid aortic valve (BAV) on valve morphology and motion as well as proximal and aortic hemodynamics...  相似文献   
9.

There are few published procedures for teaching athletic skills to children with autism spectrum disorder (ASD). This study used a multiple baseline across participants design to evaluate the effects of prompting, demand fading, and differential reinforcement, on the basketball shooting skills of four school-aged boys diagnosed with ASD. During baseline, all four boys rarely made correct and accurate baskets at the regulation height and distance for their age-group in youth basketball. Following intervention, all four boys increased their percentage of correct shots and accuracy, compared to baseline, and their shooting skills transferred to the game of “P-I-G” with peers.

  相似文献   
10.

Fears regarding various aspects tend to stimulate individuals to escape or to avoid the sources of the threat. We concluded that fears associated with the future aging process, like the fear of aging-related diseases, the fear of loneliness in old age, and the fear of death, would stimulate patterns of avoidance when it comes to ideal life expectancy. We expected fear of aging-related diseases and fear of loneliness in old age to be related to lower ideal life expectancies. We expected fear of death to be related to higher ideal life expectancies. In two adult lifespan samples [N1?=?1065 and N2?=?591; ages ranging from 18 to 95 years, M (SD)1?=?58.1 (17.2) years, M (SD)2?=?52.6 (18.1) years], we were able to support our hypothesis regarding fear of death. We furthermore found significant interactions among the fears, indicating that individuals fearing diseases or loneliness but being unafraid of death opted for the shortest lives. Our results indicate that fears regarding life in very old age might be associated with the wish to avoid this age period; the fear of death was however associated with the wish for particularly long lives, and thus, with distancing oneself from the dreaded event of death. We conclude that fears seem to be associated with how individuals approach old age and with what they wish for in their own future as aged people.

  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