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   344586篇
  免费   24102篇
  国内免费   7769篇
耳鼻咽喉   4098篇
儿科学   9655篇
妇产科学   6587篇
基础医学   28189篇
口腔科学   8187篇
临床医学   37433篇
内科学   42381篇
皮肤病学   4613篇
神经病学   19722篇
特种医学   8020篇
外国民族医学   35篇
外科学   36505篇
综合类   52146篇
现状与发展   15篇
一般理论   29篇
预防医学   35763篇
眼科学   5356篇
药学   31593篇
  376篇
中国医学   31937篇
肿瘤学   13817篇
  2023年   5481篇
  2022年   8222篇
  2021年   13140篇
  2020年   12763篇
  2019年   18505篇
  2018年   16164篇
  2017年   13085篇
  2016年   10572篇
  2015年   9899篇
  2014年   20302篇
  2013年   21933篇
  2012年   18789篇
  2011年   20262篇
  2010年   16279篇
  2009年   14914篇
  2008年   14537篇
  2007年   15093篇
  2006年   13068篇
  2005年   11346篇
  2004年   9245篇
  2003年   8133篇
  2002年   6373篇
  2001年   5693篇
  2000年   4716篇
  1999年   4036篇
  1998年   3112篇
  1997年   2983篇
  1996年   2553篇
  1995年   2634篇
  1994年   2546篇
  1993年   2042篇
  1992年   2069篇
  1991年   1779篇
  1990年   1603篇
  1989年   1416篇
  1988年   1348篇
  1987年   1149篇
  1985年   3819篇
  1984年   4821篇
  1983年   3360篇
  1982年   3824篇
  1981年   3569篇
  1980年   3176篇
  1979年   2922篇
  1978年   2551篇
  1977年   1919篇
  1976年   2160篇
  1975年   1639篇
  1974年   1436篇
  1973年   1280篇
排序方式: 共有10000条查询结果,搜索用时 93 毫秒
71.
72.
73.
《Injury》2023,54(7):110767
AimThis network meta-analysis aims to compare functional outcomes and complications between conservative treatment and surgery for distal radius fractures in patients aged 60 years and over.MethodsWe searched the PubMed, EMBASE, and Web of Science databases for randomized controlled trials (RCTs) assessing the effect of conservative treatment and surgery for distal radius fractures in patients aged 60 years and over. Primary outcomes included grip strength and overall complications. Secondary outcomes included Disabilities of the Arm, Shoulder, and Hand (DASH) scores, Patient-Rated Wrist Evaluation (PRWE) scores, wrist range of motion and forearm rotation, and radiographic assessment. All continuous outcomes were assessed using standardized mean differences (SMDs) with 95% confidence intervals (CIs), and binary outcomes were assessed using odds ratio (OR) with 95% CIs. The surface under the cumulative ranking curve (SUCRA) was used to determine a hierarchy of treatments. Cluster analysis was performed for grouping treatments based on the SUCRA values of primary outcomes.ResultsFourteen RCTs were included to compare conservative treatment, volar lockedplate (VLP), K-wires fixation, and external-fixation. VLP outperformed conservative treatment for 1-year and minimum 2-year grip strength (SMD; 0.28 [0.07 to 0.48] and 0.27 [0.02 to 0.53], respectively). VLP yielded the optimal grip strength at 1-year and minimum 2-year follow-up (SUCRA; 89.8% and 86.7%, respectively). In a subgroup analysis of patients aged 60 to 80 years old, VLP outperformed conservative treatment in DASH and PRWE scores (SMD, 0.33 [0.10, 0.56] and 0.23 [0.01, 0.45], respectively). In addition, VLP had the fewest complications (SUCRA = 84.3%). Cluster analysis suggested that VLP and K-wire fixation were more effective treatment groups.ConclusionEvidence to date demonstrates that VLP provides measurable benefits in grip strength and fewer complications to those 60 years of age and over, and that benefit is not reflected in current practice guidelines. There is a subgroup of patients where K-wire fixation outcomes are similar to those of VLP; defining this subgroup may yield substantial societal benefits.  相似文献   
74.
75.
76.
77.
PurposeTo evaluate in vivo parameters as biomarkers of limbal stem cell function and to establish an objective system that detects and stage limbal stem cell deficiency (LSCD).MethodsA total of 126 patients (172 eyes) with LSCD and 67 normal subjects (99 eyes) were included in this observational cross-sectional comparative study. Slit-lamp biomicroscopy, in vivo laser scanning confocal microscopy (IVCM), and anterior segment optical coherence tomography (AS-OCT) were performed to obtain the following: clinical score, cell morphology score, basal cell density (BCD), central corneal epithelial thickness (CET), limbal epithelial thickness (LET), total corneal nerve fiber length (CNFL), corneal nerve fiber density (CNFD), corneal nerve branch density (CNBD), and tortuosity coefficient. Their potential correlations with the severity of LSCD were investigated, and cutoff values were determined.ResultsAn increase clinical score correlated with a decrease in central cornea BCD, limbal BCD, CET, mean LET, maximum LET, CNFL, CNFD, CNBD, and tortuosity coefficient. Regression analyses showed that central cornea BCD, CET and CNFL were the best parameters to differentiate LSCD from normal eyes (Coef = 3.123, 3.379, and 2.223; all p < 0.05). The rank correlation analysis showed a similar outcome between the clinical scores and the central cornea BCD (ρ = 0.79), CET (ρ = 0.82), and CNFL (ρ = 0.71). A comprehensive LSCD grading formula based on a combination of these parameters was established.ConclusionsA comprehensive staging system combining clinical presentation, central cornea BCD, CET, and CNFL is established to accurately and objectively diagnose LSCD and stage its severity.  相似文献   
78.
In recent years, there has been increased global advocacy for the use of a collaborative, multisectoral, and transdisciplinary approach: a One Health approach, with the goal to achieve optimal health outcomes for people, animals and their shared environment. This study explored One Health implementation and practice in Kenya. Further, I used a case study of Nthongoni, a remote rural area in Eastern Kenya, to help us to understand and think about implementation of One Health in an area where mainstream biomedical system runs parallel to or is in conflict with, a deeply entrenched indigenous health system. I used a qualitative research approach including participant observation, and key informant and general respondents' in-depth interviews. Data was transcribed verbatim, translated, checked for consistency and coded for content and thematic analysis. The findings indicate that although Kenya's One Health approach was hailed as a key strategy and a model for other countries in the region, the approach faced significant challenges including insufficient funding, competing priorities and concerns over its sustainability. But while the formal One Health is embroiled in structural and politico-economic influences that curtail its operationalization and success, this study illuminates a lay one health that is part of lived realities in Nthongoni, inviting us to reflect on the place for and status of traditional healers, and meaning of health for people and animals. The study further provokes our thoughts over whether One Health should integrate or do away with traditional health systems, or be abandoned altogether. I argue that incorporating traditional health knowledge and practitioners in One Health might help to make health care more robust and culturally responsive. The work contributes to debates on anthropology of health in general and to anthropological understanding of both the lay one health and the institutional One Health agenda.  相似文献   
79.
Cantharidin (CTD) is an effective antitumor agent. However, it exhibits significant hepatotoxicity, the mechanism of which remains unclear. In this study, biochemical and histopathological analyses complemented with ultra-high-performance liquid chromatography–tandem mass spectrometry (UHPLC-MS/MS)-based targeted metabolomic analysis of bile acids (BAs) were employed to investigate CTD-induced hepatotoxicity in rats. Sixteen male and female Sprague–Dawley rats were randomly divided into two groups: control and CTD (1.0 mg/kg) groups. Serum and liver samples were collected after 28 days of intervention. Biochemical, histopathological, and BA metabolomic analyses were performed for all samples. Further, the key biomarkers of CTD-induced hepatotoxicity were identified via multivariate and metabolic pathway analyses. In addition, metabolite–gene–enzyme network and Kyoto Encyclopedia of Genes and Genomes pathway analyses were used to identify the signaling pathways related to CTD-induced hepatotoxicity. The results revealed significantly increased levels of biochemical indices (alanine aminotransferase, aspartate aminotransferase, and total bile acid). Histopathological analysis revealed that the hepatocytes were damaged. Further, 20 endogenous BAs were quantitated via UHPLC-MS/MS, and multivariate and metabolic pathway analyses of BAs revealed that hyocholic acid, cholic acid, and chenodeoxycholic acid were the key biomarkers of CTD-induced hepatotoxicity. Meanwhile, primary and secondary BA biosynthesis and taurine and hypotaurine metabolism were found to be associated with the mechanism by which CTD induced hepatotoxicity in rats. This study provides useful insights for research on the mechanism of CTD-induced hepatotoxicity.  相似文献   
80.
BackgroundIn the United States nearly 20% of children ages 12–17 have developmental disorders. Some attain population-based developmental milestones after a delay, or increase functioning through special education, medication, technology, or therapy. Others have severe lasting impairments. An indicator identifying those groups in surveys of adults could help shape policies to improve lives.HypothesesWe hypothesized that survey histories of special education could indicate functional status levels.MethodsData were from the nationally representative Panel Study of Income Dynamics (1997–2017, n = 2745). With measures of diagnoses, behaviors, functional status, service use, and adult outcomes, we tested three special education groups as indicators of: (1) no impairment (no special education), (2) disorders, developmental diagnoses that adversely affect educational performance, but with development after a period of delay or only moderate disability, indicated by transfer from special education; and (3) severe lasting disability, the diagnoses combined with life-long needs for supports or services, with limitations in areas including self-care, mobility, and capacity for independent living, indicated by special education in the individual's final year of school.ResultsAcross the special education groups, from no impairment to severe lasting disability, there were trends of: increasing severe and lasting disability (respectively 4.8%, 35.6%, 76.4%); increasing special services use (13.5%, 43.1%, 83.7%); increasing severe emotional disorders (2.3%, 11.3%, 17.9%); lower percentages attaining at least an associate's degree by age 25 (42.1%, 20.7%, and 8.9%); and more chronic diseases.ConclusionsSpecial education histories provide a useful indicator of developmental disability impairment levels in adults.  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