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   1049481篇
  免费   75317篇
  国内免费   2918篇
耳鼻咽喉   14388篇
儿科学   32584篇
妇产科学   28881篇
基础医学   146295篇
口腔科学   28376篇
临床医学   90241篇
内科学   213550篇
皮肤病学   20920篇
神经病学   84578篇
特种医学   42279篇
外国民族医学   338篇
外科学   165302篇
综合类   21526篇
现状与发展   1篇
一般理论   435篇
预防医学   79120篇
眼科学   23627篇
药学   74850篇
  3篇
中国医学   1982篇
肿瘤学   58440篇
  2021年   8607篇
  2019年   9017篇
  2018年   12221篇
  2017年   9409篇
  2016年   10090篇
  2015年   11642篇
  2014年   16631篇
  2013年   25649篇
  2012年   34991篇
  2011年   37187篇
  2010年   22049篇
  2009年   20879篇
  2008年   34954篇
  2007年   37164篇
  2006年   36851篇
  2005年   36586篇
  2004年   34965篇
  2003年   33536篇
  2002年   32908篇
  2001年   43380篇
  2000年   44401篇
  1999年   38348篇
  1998年   11756篇
  1997年   10547篇
  1996年   10472篇
  1995年   9780篇
  1994年   9221篇
  1993年   8696篇
  1992年   29617篇
  1991年   28401篇
  1990年   27756篇
  1989年   26590篇
  1988年   24744篇
  1987年   24334篇
  1986年   23457篇
  1985年   22375篇
  1984年   17039篇
  1983年   14661篇
  1982年   9335篇
  1979年   15566篇
  1978年   11127篇
  1977年   9396篇
  1976年   8841篇
  1975年   9607篇
  1974年   11425篇
  1973年   10856篇
  1972年   10176篇
  1971年   9463篇
  1970年   9051篇
  1969年   8415篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
91.
92.
First described in 1955 in New Jersey, epizootic haemorrhagic disease (EHD) causes a severe clinical disease in wild and domestic ruminants worldwide. Epizootic haemorrhagic disease outbreaks occur in deer populations each year from summer to late autumn. The etiological agent is EHD virus (EHDV) which is a double‐stranded segmented icosahedral RNA virus. EHD virus utilizes point mutations and reassortment strategies to maintain viral fitness during infection. In 2018, EHDV serotype 2 was predominantly detected in deer in Illinois. Whole genome sequencing was conducted for two 2018 EHDV2 isolates (IL41747 and IL42218) and the sequence analyses indicated that IL42218 was a reassortant between different serotypes whereas IL41747 was a genetically stable strain. Our data suggest that multiple strains contribute to outbreaks each year.  相似文献   
93.
Fibroepithelial polyps (FEPs) are common, benign intraoral lesions that tend to develop slowly at predictable sites, often in response to local irritation or trauma. Historical precedent often results in referral to oral and maxillofacial surgery (OMFS) departments for biopsy, often irrespective of symptoms, and histological assessment. OMFS and pathology services are struggling to cope with an increasing workload that will potentially lead to widespread delays to diagnosis and treatment. Over the past 20 years, clinical pathways and guidance have been developed to ensure that healthcare interventions, such as the removal of third molars, tonsils, skin tags, and benign moles, are evidence-based, have a net patient benefit, and ensure the best use of finite NHS resources. However, no such guidance exists for intraoral lesions and we regard this as an oversight. We analysed the removal of 682 FEPs over a seven-year period and report sensitivities of 92.4% for a “confirmed clinical suspicion of an FEP” and 99.7% for a “confirmed clinical suspicion of a benign diagnosis”. The incidence of non-benign disease was 0.3%. Primary care dentists should be able to diagnose and monitor FEPs and refer only if symptoms are serious or in high-risk patients or sites. Adopting this practice across the UK could free up to 1825 four-hour OMFS clinics, 405 hours of consultant histopathologists’ time, and recurring savings to the NHS estimated to be in the region of £620 000/annum. We believe that the removal of FEPs should be reclassified as an “intervention not normally funded”, and the time and resources put to better use treating patients with lesions of questionable pathology.  相似文献   
94.
Journal of Behavioral Medicine - Understanding associations between mothers’ and children’s physical activity and sedentary behavior on more fine-grained timescales can provide insights...  相似文献   
95.
96.
In both adults and children with diabetes, technologies such as continuous subcutaneous insulin infusion using insulin pumps and continuous glucose monitoring can help improve diabetes control, reduce hypoglycaemia and improve quality of life. Access to these technologies in the UK is very variable. Some technologies are recommended by the National Institute for Health and Care Excellence, while others have not been appraised, and new technologies are emerging all the time. Additionally, different guidelines for adults and children further complicate access to diabetes technology in the transition from paediatric to adult care. Against this background, Diabetes UK and NHS England have brought together a multidisciplinary group of experts, including clinicians and people with diabetes, to develop this consensus guideline, combining the different technologies into a common pathway to aid clinical and policy decision‐making. We created a pathway that supports the incremental addition of technology as monotherapy and then dual therapy in the same way that we incrementally add in therapeutic agents to support people with Type 2 diabetes to achieve their personalized glycaemic targets. The pathway emphasizes the importance of structured education, specialist support and appropriate access to psychological therapies, as essential pillars for optimized use of diabetes‐related technology, and recommends the re‐evaluation of its use when the individual is unable either to use the technology appropriately or to achieve the intended outcomes. This pathway is endorsed by UK‐wide clinical and patient associations and we recommend that providers and commissioners use it to ensure the right individual with diabetes has access to the right technology in a timely way to help achieve better outcomes.  相似文献   
97.

Background Context

Low back pain (LBP) is a common complaint in clinical practice of multifactorial origin. Although obesity has been thought to contribute to LBP primarily by altering the distribution of mechanical loads on the spine, the additional contribution of obesity-related conditions such as diabetes mellitus (DM) to LBP has not been thoroughly examined.

Purpose

To determine if there is a relationship between DM and LBP that is independent of body mass index (BMI) in a large cohort of adult survey participants.

Study Design

Retrospective analysis of prospectively collected National Health and Nutrition Examination Survey (NHANES) data to characterize associations between LBP, DM, and BMI in adults subdivided into 6 subpopulations: normal weight (BMI 18.5–25), overweight (BMI 25–30), and obese (BMI >30) diabetics and nondiabetics. Diabetes was defined with glycohemoglobin A1c (HbA1c) 6.5%.

Patient Sample

11,756 participants from NHANES cohort.

Outcome Measures

Percentage of LBP reported.

Methods

LBP reported in the 1999-2004 miscellaneous pain NHANES questionnaire was the dependent variable examined. Covariates included HbA1c, BMI, age, and family income ratio to poverty as continuous variables as well as race, gender, and smoking as binary variables. Individuals were further subdivided by weight class and diabetes status. Regression and graphical analyses were performed on the study population as a whole and also on subpopulations.

Results

Increasing HbA1c did not increase the odds of reporting LBP in the full cohort. However, multivariate logistic regression of the 6 subpopulations revealed that the odds of LBP significantly increased with increasing HbA1c levels in normal weight diabetics. No other subpopulations reported significant relationships between LBP and HbA1c. LBP was also significantly associated with BMI for normal weight diabetics and also for obese subjects regardless of their DM status.

Conclusions

LBP is significantly related to DM status, but this relationship is complex and may interact with BMI. These results support the concept that LBP may be improved in normal weight diabetic subjects with improved glycemic control and weight loss, and that all obese LBP subjects may benefit from improved weight loss alone.  相似文献   
98.
99.
100.
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