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   41170篇
  免费   3229篇
  国内免费   1476篇
耳鼻咽喉   466篇
儿科学   877篇
妇产科学   450篇
基础医学   3186篇
口腔科学   1577篇
临床医学   4760篇
内科学   6732篇
皮肤病学   1162篇
神经病学   1888篇
特种医学   1772篇
外科学   2635篇
综合类   6943篇
现状与发展   10篇
一般理论   4篇
预防医学   5337篇
眼科学   2952篇
药学   2782篇
  26篇
中国医学   1791篇
肿瘤学   525篇
  2024年   109篇
  2023年   793篇
  2022年   1445篇
  2021年   2007篇
  2020年   1889篇
  2019年   1429篇
  2018年   1361篇
  2017年   1313篇
  2016年   1568篇
  2015年   1411篇
  2014年   2744篇
  2013年   2901篇
  2012年   2540篇
  2011年   2732篇
  2010年   2265篇
  2009年   2133篇
  2008年   2076篇
  2007年   2032篇
  2006年   1779篇
  2005年   1610篇
  2004年   1272篇
  2003年   1187篇
  2002年   963篇
  2001年   928篇
  2000年   741篇
  1999年   565篇
  1998年   544篇
  1997年   436篇
  1996年   305篇
  1995年   393篇
  1994年   318篇
  1993年   214篇
  1992年   238篇
  1991年   215篇
  1990年   178篇
  1989年   180篇
  1988年   162篇
  1987年   155篇
  1986年   126篇
  1985年   116篇
  1984年   95篇
  1983年   59篇
  1982年   54篇
  1981年   36篇
  1980年   33篇
  1979年   50篇
  1978年   32篇
  1977年   33篇
  1976年   30篇
  1975年   20篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
阿尔茨海默病是一种进行性且不可逆转的神经系统疾病,由于视网膜和中枢神经系统有相似的胚胎起源和生理特征,眼科检查可提供简单无创的诊断方法。光学相干断层扫描技术(OCT)能够精确地测量视网膜各个组织层面的厚度,以评估视网膜的退行性改变,光学相干断层扫描血管成像(OCTA)可以提供高分辨率三维成像,从而更直观地检测视网膜血管的变化,间接地反映脑神经元和血管的病理特征。就OCT测量视网膜厚度及OCTA测量视网膜血流变化在阿尔茨海默病诊断中的研究进展进行综述。  相似文献   
2.
3.
宫颈癌对妇女健康构成严重威胁,人乳头瘤病毒感染与宫颈病变及宫颈癌的发生密切相关。关于宫颈癌发生发展的机制仍在研究中。近年研究发现一种多功能核蛋白,即死亡结构域相关蛋白(death domain associated protein,Daxx),其与细胞内蛋白或病毒蛋白相互作用,参与调节细胞凋亡、转录调控、抗病毒等细胞活动,在不同途径中发挥不同的生理或病理作用。通过对Daxx功能及其作用机制的研究有助于进一步阐明宫颈癌发生发展的机制,有助于发现新的预防和治疗方法。综述Daxx的一般特性和研究现况及其在宫颈病变的研究进展。  相似文献   
4.
《Australian critical care》2019,32(6):540-559
ObjectivesThe objective of this review was to describe cardiovascular risk (CVR) assessment methods and to identify evidence-based practice recommendations when dealing with population at risk of developing cardiovascular diseases.Review methods and data sourcesA literature review following the Arksey and O'Malley scoping review methodology was conducted. By using appropriate key terms, literature searches were conducted in PubMed, SciELO, Cochrane Library, Dialnet, ENFISPO, Medigraphic, ScienceDirect, Cuiden, and Lilacs databases. A complementary search on websites related to the area of interest was conducted. Articles published in English or Spanish in peer-review journals between 2010 and 2017. Critical appraisal for methodological quality was conducted. Data was extracted using ad-hoc tables and qualitatively synthesized.ResultsAfter eliminating duplicates, 55 325 records remained, and 1432 records were selected for screening. Out of these, 88 full-text articles were selected for eligibility criteria, and finally, 67 studies were selected for this review, and 25 studies were selected for evidence synthesis. In total, 23 CVR assessment tools have been identified, pioneered by the Framingham study. Qualitative findings were grouped into four thematic areas: assessment tools and scores, CVR indicators, comparative models, and evidence-based recommendations.ConclusionsIt is necessary to adapt the instruments to the epidemiological reality of the population. The most appropriate way to estimate CVR is to choose the assessment tool that best suits individual conditions, accompanied by a comprehensive assessment of the patient. More research is required to determine a single, adequate, and reliable tool.  相似文献   
5.
We reported two cases with community-acquired pneumonia caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) who returned from Wuhan, China in January, 2020. The reported cases highlight non-specific clinical presentations of 2019 novel coronavirus disease (COVID-19) as well as the importance of rapid laboratory-based diagnosis.  相似文献   
6.
A classic pilomatricoma, which usually presents with an asymptomatic, solitary, firm, subcutaneous nodule in the head, neck, or extremities of the paediatric population, is easily diagnosed based on its characteristic clinical and histopathological features. However, its variants often pose particular diagnostic challenges to clinicians due to their rarity and diverse clinicopathological features. We present a new pseudocystic variant, manifesting as solid lesions floating in a fluid‐filled sac.  相似文献   
7.
There is increasing public interest in natural or herbal-based healthcare products. This trend is not only visible in supermarkets and dental practices, but also in the scientific world. An improving number of clinical trials are being conducted to validate the claims made about these products in regards to periodontal health. Among single component preparations, Aloe vera and green tea are the most studied natural ingredients. Concerning polyherbal mixtures, triphala has garnered great interest. The effects of these natural products on periodontal health is encouraging, with almost all studies showing an inhibitory effect on plaque accumulation and an improvement in gingival health. However, more studies are needed to be able to design clinical guidelines to guide the use of these natural products in periodontal practice. For most of these products, few studies are available and, moreover, the available studies are limited in duration, the number of participants, and the specific composition of the natural product is often not described in detail.  相似文献   
8.
9.
BackgroundDuring their training, students in osteopathy regularly undergo spinal manipulation exercises. This exposes the students’ spine to unskilled gestures performed by their colleagues learning spinal manipulation. Discomfort, muscle soreness or moderate pain following spinal manipulations lasting two or three days are commonly reported. In addition, some students may have ongoing spinal musculoskeletal disease (SMSD) during their studies. The purpose of this study was to evaluate the prevalence of SMSDs and their maximum intensity in a population of osteopathy students and to determine whether individual differences exist.MethodAn exploratory cross-sectional study took place over three years. Data were collected by means of a self-administrated standardised questionnaire screening for MSD: the Nordic questionnaire.ResultsThere were 733 exploitable questionnaires, giving an average response rate of 91.5%. Average prevalence of SMSD was 98.4% during the last 12 months. Average maximum intensity perceived was 6/10 and 45% of students experienced an intense SMSD (scored between 7 and 10/10). Variation of the maximum intensity of SMSD between “before osteopathy studies” and “the last 12 months” was 1.2/10. This variation was influenced by the number of days students were manipulated during a week (p < 0.0001). On average, students underwent manipulation three days a week.ConclusionThis study confirms the important prevalence of SMSD among osteopathy students. This result led us to carry out a qualitative study for exploring students’ conceptions in health and spinal manipulative practices.  相似文献   
10.
Over 36 million people worldwide are infected with HIV. Antiretroviral therapy (ART) has proven to be highly effective to prevent HIV-1 transmission, clinical progression and death. Despite this success, the number of HIV-1 infected individuals continues increasing and ART should be taken for life. Therefore, there are two main priorities: the development of preventive vaccines to protect from HIV acquisition and achieve an efficient control of HIV infection in the absence of ART (functional cure). In this sense, in the last few years, there has been a broad interest in new and innovative approaches such as mRNA-based vaccines. RNA-based immunogens represent a promising alternative to conventional vaccines because of their high potency, capacity for rapid development and potential for low-cost manufacture and safe administration. Some mRNA-based vaccines platforms against infectious diseases have demonstrated encouraging results in animal models and humans. However, their application is still limited because the instability and inefficient in vivo delivery of mRNA. Immunogens, design, immunogenicity, chemical modifications on the molecule or the vaccine delivery methods are all crucial interventions for improvement. In this review we, will present the current knowledge and challenges in this research field. mRNA vaccines hold great promises as part of a combined strategy, for achieving HIV functional cure.  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