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   348031篇
  免费   27863篇
  国内免费   11839篇
耳鼻咽喉   1774篇
儿科学   10436篇
妇产科学   2817篇
基础医学   31430篇
口腔科学   6040篇
临床医学   33529篇
内科学   83144篇
皮肤病学   3588篇
神经病学   31747篇
特种医学   10401篇
外国民族医学   21篇
外科学   33222篇
综合类   48908篇
现状与发展   48篇
一般理论   10篇
预防医学   29442篇
眼科学   3512篇
药学   29099篇
  306篇
中国医学   18126篇
肿瘤学   10133篇
  2023年   6486篇
  2022年   10431篇
  2021年   17045篇
  2020年   15549篇
  2019年   14223篇
  2018年   13461篇
  2017年   13193篇
  2016年   12899篇
  2015年   12466篇
  2014年   22605篇
  2013年   24544篇
  2012年   19228篇
  2011年   21118篇
  2010年   16553篇
  2009年   16040篇
  2008年   15979篇
  2007年   15695篇
  2006年   14056篇
  2005年   11731篇
  2004年   9764篇
  2003年   8481篇
  2002年   7035篇
  2001年   6158篇
  2000年   5220篇
  1999年   4420篇
  1998年   4086篇
  1997年   3637篇
  1996年   3255篇
  1995年   2934篇
  1994年   2740篇
  1993年   2271篇
  1992年   2166篇
  1991年   1841篇
  1990年   1540篇
  1989年   1315篇
  1988年   1170篇
  1987年   1070篇
  1986年   919篇
  1985年   2470篇
  1984年   3330篇
  1983年   2834篇
  1982年   2337篇
  1981年   2340篇
  1980年   1928篇
  1979年   1679篇
  1978年   1424篇
  1977年   901篇
  1976年   1334篇
  1975年   1067篇
  1974年   891篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
《Vaccine》2022,40(52):7604-7612
Background and ObjectiveVaccine uptake during pregnancy remains low. Our objectives were to describe 1) development and adaptation of a clinician communication training intervention for maternal immunizations and 2) obstetrics and gynecology (ob-gyn) clinician and staff perspectives on the intervention and fit for the prenatal care context.MethodsDesign of the Motivational Interviewing for Maternal Immunizations (MI4MI) intervention was based on similar communication training interventions for pediatric settings and included presumptive initiation of vaccine recommendations (“You’re due for two vaccines today”) combined with motivational interviewing (MI) for hesitant patients. Interviews and focus group discussions were conducted with ob-gyn clinicians and staff in five Colorado clinics including settings with obstetric physicians, certified nurse midwives (CNMs), and clinician-trainees. Participants were asked about adapting training to the ob-gyn setting and their implementation experiences. Feedback was incorporated through iterative changes to training components.ResultsInterview and focus group discussion results from participants before (n = 3), during (n = 11) and after (n = 25) implementation guided intervention development and adaptation. Three virtual, asynchronous training components were created: a video and two interactive modules. This virtual format was favored due to challenges attending group meetings; however, participants noted opportunities to practice skills through role-play were lacking. Training modules were adapted to include common challenging vaccine conversations and live-action videos. Participants liked interactive training components and use of adult learning strategies. Some participants initially resisted the presumptive approach but later found it useful after applying it in their practices. Overall, participants reported that MI4MI training fit well with the prenatal context and recommended more inclusion of non-clinician staff.ConclusionsMI4MI training was viewed as relevant and useful for ob-gyn clinicians and staff. Suggestions included making training more interactive, and including more complex scenarios and non-clinician staff.  相似文献   
2.
3.
《Saudi Pharmaceutical Journal》2022,30(11):1572-1588
Non-alcoholic fatty liver disease (NAFLD) is one of the most common complications of a metabolic syndrome caused by excessive accumulation of fat in the liver. Orthosiphon stamineus also known as Orthosiphon aristatus is a medicinal plant with possible potential beneficial effects on various metabolic disorders. This study aims to investigate the in vitro inhibitory effects of O. stamineus on hepatic fat accumulation and to further use the computational systems pharmacology approach to identify the pharmacokinetic properties of the bioactive compounds of O. stamineus and to predict their molecular mechanisms against NAFLD. Methods: The effects of an ethanolic extract of O. stamineus leaves on cytotoxicity, fat accumulation and antioxidant activity were assessed using HepG2 cells. The bioactive compounds of O. stamineus were identified using LC/MS and two bioinformatics databases, namely the Traditional Chinese Medicine Integrated Database (TCMID) and the Bioinformatics Analysis Tool for the Molecular Mechanism of Traditional Chinese Medicine (BATMAN-TCM). Pathway enrichment analysis was performed on the predicted targets of the bioactive compounds to provide a systematic overview of the molecular mechanism of action, while molecular docking was used to validate the predicted targets. Results: A total of 27 bioactive compounds corresponding to 50 potential NAFLD-related targets were identified. O. stamineus exerts its anti-NAFLD effects by modulating a variety of cellular processes, including oxidative stress, mitochondrial β-oxidation, inflammatory signalling pathways, insulin signalling, and fatty acid homeostasis pathways. O. stamineus is significantly targeting many oxidative stress regulators, including JNK, mammalian target of rapamycin (mTOR), NFKB1, PPAR, and AKT1. Molecular docking analysis confirmed the expected high affinity for the potential targets, while the in vitro assay indicates the ability of O. stamineus to inhibit hepatic fat accumulation. Conclusion: Using the computational systems pharmacology approach, the potentially beneficial effect of O. stamineus in NAFLD was indicated through the combination of multiple compounds, multiple targets, and multicellular components.  相似文献   
4.
5.
A 25-year-old, emaciated man without medical treatment was found to have died suddenly at home by his mother. At autopsy, there were no injuries to his body, but significant circulatory insufficiency was observed. Electron microscopy revealed abnormal mitochondria in cells of the cardiac conduction system. The conduction system was filled with mitochondrial size abnormalities and mitochondrial cristae abnormalities. No notable abnormal findings were observed in other organs. Genetic examination of the blood revealed the mitochondrial pathogenetic variant m.3243A>G. Epileptic seizures, diabetic ketoacidosis, and hyperosmolar hyperglycemic state were unlikely to be the cause of sudden death. The cause of death was diagnosed as arrhythmia possibly induced by the failure of the cardiac conduction system due to mitochondrial disease. This is a rare case of sudden death caused by an accumulation of abnormal mitochondria in the cardiac conduction system.  相似文献   
6.
7.
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   
8.
IntroductionDetailed data on clinical characteristics in children with the omicron strain of SARS-COV-2 are limited.MethodsWe conducted a retrospective observational study of children with COVID-19 at the National Center for Child Health and Development to evaluate the clinical manifestations during and before the emergence of the omicron variant. Only symptomatic patients without underlying diseases were included. Participants were divided into two temporal groups: the “omicron era” (1/2022–2/2022) and the “pre-omicron era,” where the delta variant predominated (7/2021–11/2021). The patients were subclassified into an older vaccine-eligible group (aged 12–17 years), a younger vaccine-eligible group (aged 5–11 years), and a vaccine-ineligible group (aged 0–4 years).ResultsWe compared 113 patients in the omicron era with 106 in the pre-omicron era. Most patients in both eras had non-severe disease, and no patients required mechanical ventilation or died. Among patients aged 0–4 years, sore throat and hoarseness were more common during the omicron era than the pre-omicron era (11.1% vs. 0.0% and 11.1% vs. 1.5%, respectively). Croup syndrome was diagnosed in all patients with hoarseness. Among patients aged 5–11 years, vomiting was more frequent during the omicron era (47.2%) than during the pre-omicron era (21.7%). Cough and rhinorrhea were less common during the omicron era in patients aged 0–4 and 5–11 years, respectively, than during the pre-omicron era.ConclusionsIn children with COVID-19, clinical manifestations differed between the omicron and pre-omicron eras. In the Omicron era, croup syndrome was more frequent in vaccine-ineligible children.  相似文献   
9.
黄晓云  陈玲 《现代肿瘤医学》2022,(21):3944-3947
目的:探讨初诊急性白血病患者化疗期间应用伏立康唑进行预防侵袭性真菌病(IFD)的临床疗效及安全性。方法:回顾性分析2016年02月至2018年03月期间我院血液科收治的初诊急性白血病行化疗的患者166例,按照是否使用抗真菌药进行预防性治疗分为观察组(应用伏立康唑进行预防治疗,n=103)和对照组(未应用抗真菌药物,n=63),比较两组患者IFD发生率差异,并分析抗真菌药物应用的不良反应。结果:观察组IFD发生率为10.7%,对照组为33.3%,两组患者的IFD发生率有明显差异(P<0.05);所有应用伏立康唑进行预防治疗的患者均未出现严重的不良反应。结论:伏立康唑可以有效减低急性白血病患者化疗期间IFD发生率,并且有着较好的安全性,值得在临床推广应用。  相似文献   
10.
BackgroundWe aimed to describe the effectiveness and safety of inhaled antibiotics in chronic obstructive pulmonary disease (COPD) patients, as well as the patient profile in which they are usually prescribed and the patient groups that can most benefit from this treatment.MethodsMulticentre retrospective observational cohort study in COPD patients who had received ≥1 dose of inhaled antibiotics in the last 5 years. Clinical data from the two years prior to and subsequent to the start of the treatment were compared. Primary outcome: COPD exacerbations. Secondary outcomes: side effects, symptomatology (sputum purulence, dyspnoea), microbiological profile and pathogen eradication.ResultsOf 693 COPD patients analyzed (aged 74.1; 86.3% men; mean FEV1 = 43.7%), 71.7% had bronchiectasis and 46.6% presented chronic bronchial infection (CBI) by Pseudomonas aeruginosa (PA). After 1 year of treatment with inhaled antibiotics, there was a significant decrease in the number of exacerbations (?33.3%; P < .001), hospital admissions (?33.3%; P < .001) and hospitalization days (?26.2%; P = .003). We found no difference in effectiveness between patients with or without associated bronchiectasis. Positive patient outcomes were more pronounced in PA-eradicated patients. We found a significant reduction in daily expectoration (?33.1%; P = .024), mucopurulent/purulent sputum (?53.9%; P < .001), isolation of any potentially pathogenic microorganisms (PPM) (?16.7%; P < .001), CBI by any PPM (?37.4%; P < .001) and CBI by PA (?49.8%; P < .001). CBI by any PPM and ≥three previous exacerbations were associated with a better treatment response. 25.4% of patients presented non-severe side-effects, the most frequent of these being bronchospasm (10.5%), dyspnoea (8.8%) and cough (1.7%).ConclusionsIn COPD patients with multiple exacerbations and/or CBI by any PPM (especially PA), inhaled antibiotics appear to be an effective and safe treatment, regardless of the presence of bronchiectasis.  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