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   50851篇
  免费   4136篇
  国内免费   1112篇
耳鼻咽喉   305篇
儿科学   1369篇
妇产科学   892篇
基础医学   6951篇
口腔科学   787篇
临床医学   4899篇
内科学   10695篇
皮肤病学   943篇
神经病学   3590篇
特种医学   939篇
外国民族医学   5篇
外科学   4367篇
综合类   4713篇
现状与发展   6篇
一般理论   49篇
预防医学   5449篇
眼科学   725篇
药学   4545篇
  28篇
中国医学   1308篇
肿瘤学   3534篇
  2024年   139篇
  2023年   2915篇
  2022年   6403篇
  2021年   8066篇
  2020年   5561篇
  2019年   1976篇
  2018年   1761篇
  2017年   1486篇
  2016年   1236篇
  2015年   1321篇
  2014年   2025篇
  2013年   1908篇
  2012年   1864篇
  2011年   2148篇
  2010年   1933篇
  2009年   1568篇
  2008年   1527篇
  2007年   1410篇
  2006年   1146篇
  2005年   1009篇
  2004年   969篇
  2003年   757篇
  2002年   573篇
  2001年   482篇
  2000年   500篇
  1999年   407篇
  1998年   324篇
  1997年   269篇
  1996年   267篇
  1995年   213篇
  1994年   162篇
  1993年   148篇
  1992年   122篇
  1991年   122篇
  1990年   98篇
  1989年   80篇
  1988年   64篇
  1987年   58篇
  1985年   353篇
  1984年   520篇
  1983年   326篇
  1982年   346篇
  1981年   377篇
  1980年   252篇
  1979年   293篇
  1978年   165篇
  1977年   137篇
  1976年   81篇
  1975年   60篇
  1973年   57篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
PurposeAccording to the social determinants of health framework, income inequality is a potential risk factor for adverse mental health. However, few studies have explored the mechanisms suspected to mediate this relationship. The current study addresses this gap through a mediation analysis to determine if social support and community engagement act as mediators linking neighbourhood income inequality to maternal anxiety and depressive symptoms within a cohort of new mothers living in the City of Calgary, Canada.MethodsData collected at three years postpartum from mothers belonging to the All Our Families (AOF) cohort were used in the current study. Maternal data were collected between 2012 and 2015 and linked to neighbourhood socioeconomic data from the 2006 Canadian Census. Income inequality was measured using Gini coefficients derived from 2006 after-tax census data. Generalized structural equation models were used to quantify the associations between income inequality and mental health symptoms, and to assess the potential direct and indirect mediating effects of maternal social support and community engagement.ResultsIncome inequality was not significantly associated with higher depressive symptoms (β = 0.32, 95%CI = −0.067, 0.70), anxiety symptoms (β = 0.11, 95%CI = −0.39, 0.60), or lower social support. Income inequality was not associated with community engagement. For the depression models, higher social support was significantly associated with lower depressive symptoms (β = −0.13, 95%CI = −0.15, −0.097), while community engagement was not significantly associated with depressive symptoms (β = 0.059, 95%CI = −0.15, 0.27). Similarly, for the anxiety models, lower anxiety symptoms were significantly associated with higher levels of social support (β = −0.17, 95%CI = −0.20, −0.13) but not with higher levels of community engagement (β = 0.14, 95%CI = −0.14, 0.41).ConclusionThe current study did not find clear evidence for social support or community engagement mediating the relationship between neighbourhood income inequality and maternal mental health. Future investigations should employ a broader longitudinal approach to capture changes in income inequality, potential mediators, and mental health symptomatology over time.  相似文献   
2.
《Vaccine》2022,40(52):7515-7519
The recent wave of COVID-19 cases has led to the potential need for booster doses. We surveyed 6,294 people and found that 87.6% reported willingness to take a booster dose, with vaccine efficacy rate being the most common reason cited to accept booster dose. Differences in acceptance rates were noted among those working in non-health related sectors, different ethnic groups as well as those who had taken viral vector vaccines.  相似文献   
3.
IntroductionSevere acute respiratory syndrome coronavirus 2 (SARS-CoV-2) first broke out in Wuhan in December 2019, and has since caused a global pandemic. The efficacy of several drugs has been evaluated, and it is now evident that tocilizumab has a beneficial effect, especially combined with corticosteroids, in patients with Coronavirus Disease 2019 (COVID-19). However, the optimal timing of tocilizumab administration has not yet been established. The goal of the present study was to determine the optimal timing of tocilizumab administration after starting corticosteroid therapy in patients with COVID-19.MethodsWe retrospectively analyzed the clinical characteristics of patients who were hospitalized for COVID-19 and treated with tocilizumab and corticosteroids in our hospital. The patients were divided into concurrent and sequential groups. The concurrent group received tocilizumab ≤24 h after corticosteroids, and the sequential group received tocilizumab >24 h after corticosteroid administration.ResultsThe baseline clinical characteristics of tocilizumab administration were similar between the two groups. White blood cell counts were significantly lower and C-reactive protein levels were significantly higher in the concurrent group than the sequential group. In the concurrent group, tocilizumab administration led to a significant decrease in maximum body temperature. In addition, there were significantly more oxygen-free days in the concurrent group than in the sequential group. However, survival rate was not significantly different between the concurrent and the sequential groups.ConclusionsIn the combination therapy with tocilizumab and corticosteroids, early administration of tocilizumab after starting corticosteroid treatment is effective when treating COVID-19.  相似文献   
4.
Defining con-founders that affect the reliability of diagnostic tests for coronavirus disease 2019 is vital to breaking the chain of infection. The elderly population is a higher risk group for the emerging virus. However, gender seems to exert a critical role in modifying the infection risk among women owing to hormonal changes. The menopause transition is an exceptional period for older women where the protective and immunomodulatory effects of the estrogen hormone are lost. Accordingly, attention should be given to postmenopausal women since they will have an increased risk compared to their pre-menopausal peers.  相似文献   
5.
《Cancer cell》2022,40(8):835-849.e8
  1. Download : Download high-res image (220KB)
  2. Download : Download full-size image
  相似文献   
6.
7.
8.
《Vaccine》2022,40(27):3721-3726
We initiated a randomized, placebo-controlled, phase 1/2 trial to evaluate the safety and immunogenicity of the S-268019-b recombinant protein vaccine, scheduled as 2 intramuscular injections given 21 days apart, in 60 randomized healthy Japanese adults. We evaluated 2 regimens of the S-910823 antigen (5 μg [n = 24] and 10 μg [n = 24]) with an oil-in-water emulsion formulation and compared against placebo (n = 12). Reactogenicity was mild in most participants. No serious adverse events were noted. For both regimens, vaccination resulted in robust IgG and neutralizing antibody production at days 36 and 50 and predominant T-helper 1-mediated immune reaction, as evident through antigen-specific polyfunctional CD4+ T-cell responses with IFN-γ, IL-2, and IL-4 production on spike protein peptides stimulation. Based on the interim analysis, the S-268019-b vaccine is safe, produces neutralizing antibodies titer comparable with that in convalescent serum from COVID-19-recovered patients. However, further evaluation of the vaccine in a large clinical trial is warranted.  相似文献   
9.
BackgroundTraditional Chinese medicine (TCM) has been proven to played a great important role on the treatment of COVID-19. As one of the drugs recommended in Chinese guidelines, Lianhua Qingwen Granules or Capsules (LQ) are widely used.This systematic review and meta-analysis amis to evaluate the clinical efficacy of LQ on the treatment of COVID-19.MethodsSeven databases (PubMed, EMBASE, CENTRAL, CNKI, VIP, CBM and Wanfang) were searched to include all appropriate clinical trials that explore the efficacy of LQ on the treatment of COVID-19.ResultA total of 3 trials including 245 COVID-19 patients were eventually enrolled.Compared with the control group,the LQ group showed great significant difference on reducing the rate of clinical change to severe or critical condition[RR = 0.38, 95 %CI (0.17,0.85), P < 0.05]and the fever time (SMD =-0.57,95 %CI (-0.96,-0.17), P<0.05),as well as the significant improvement on the disappearance rate of the clinical symptoms: fever [RR = 1.36,95 %CI (1.14,1.61), P < 0.05],cough[RR = 1.99,95 %CI (1.39,2.86), P < 0.05],fatigue[RR = 1.52,95 %CI (1.15,2.01), P < 0.05] and anhelation [RR = 4.18,95 %CI (1.99,8.81), P < 0.05], but no significance on expectoration[RR = 2.46,95 %CI (0.81,7.51), P < 0.05].ConclusionThe clinical application of LQ on the treatment of COVID-19 has significant efficacy in improving clinical symptoms and reducing the rate of clinical change to severe or critical condition. Nevertheless, due to the limited quantity and quality of the included studies, more and higher quality trials with more observational indicators are expected to be published.  相似文献   
10.
The coronavirus disease 2019 (COVID-19) pandemic has rapidly created widespread impacts on global health and the economy. Data suggest that women are less susceptible to severe illness. However, sex-disaggregated data are incomplete, leaving room for misinterpretation, and focusing only on biologic sex underestimates the gendered impact of the pandemic on women. This narrative review summarizes what is known about gender disparities during the COVID-19 pandemic and the economic, domestic, and health burdens along with overlapping vulnerabilities related to the pandemic. In addition, this review outlines recommended strategies that advocacy groups, community leaders, and policymakers should implement to mitigate the widening gender disparities related to COVID-19.  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