全文获取类型
收费全文 | 18303篇 |
免费 | 1364篇 |
国内免费 | 592篇 |
专业分类
耳鼻咽喉 | 100篇 |
儿科学 | 606篇 |
妇产科学 | 468篇 |
基础医学 | 1690篇 |
口腔科学 | 87篇 |
临床医学 | 1140篇 |
内科学 | 4982篇 |
皮肤病学 | 175篇 |
神经病学 | 1058篇 |
特种医学 | 389篇 |
外国民族医学 | 3篇 |
外科学 | 2208篇 |
综合类 | 2012篇 |
现状与发展 | 3篇 |
预防医学 | 1474篇 |
眼科学 | 140篇 |
药学 | 2091篇 |
中国医学 | 1110篇 |
肿瘤学 | 523篇 |
出版年
2024年 | 61篇 |
2023年 | 416篇 |
2022年 | 799篇 |
2021年 | 787篇 |
2020年 | 642篇 |
2019年 | 1217篇 |
2018年 | 1233篇 |
2017年 | 626篇 |
2016年 | 512篇 |
2015年 | 499篇 |
2014年 | 1007篇 |
2013年 | 1120篇 |
2012年 | 931篇 |
2011年 | 959篇 |
2010年 | 695篇 |
2009年 | 634篇 |
2008年 | 636篇 |
2007年 | 672篇 |
2006年 | 636篇 |
2005年 | 594篇 |
2004年 | 529篇 |
2003年 | 497篇 |
2002年 | 352篇 |
2001年 | 325篇 |
2000年 | 290篇 |
1999年 | 263篇 |
1998年 | 222篇 |
1997年 | 235篇 |
1996年 | 227篇 |
1995年 | 206篇 |
1994年 | 225篇 |
1993年 | 195篇 |
1992年 | 161篇 |
1991年 | 136篇 |
1990年 | 135篇 |
1989年 | 158篇 |
1988年 | 137篇 |
1987年 | 121篇 |
1986年 | 112篇 |
1985年 | 138篇 |
1984年 | 141篇 |
1983年 | 117篇 |
1982年 | 109篇 |
1981年 | 113篇 |
1980年 | 95篇 |
1979年 | 67篇 |
1978年 | 54篇 |
1977年 | 42篇 |
1976年 | 35篇 |
1974年 | 37篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
1.
《Archivos de bronconeumología》2022,58(1):11-21
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
2.
Xiumei Jiang Xiaowei Zhang Patrick Gray Jiwen Zheng Timothy R. Croley Peter P. Fu 《journal of environmental science and health part c-environmental carcinogenesis & ecotoxicology reviews》2019,37(2):116-131
Gold nanoparticles (Au NPs) hold great promise in food, industrial and biomedical applications due to their unique physicochemical properties. However, influences of the gastrointestinal tract (GIT), a likely route for Au NPs administration, on the physicochemical properties of Au NPs has been rarely evaluated. Here, we investigated the influence of GIT fluids on the physicochemical properties of Au NPs (5, 50, and 100?nm) and their implications on intestinal epithelial permeability in vitro. Au NPs aggregated in fasted gastric fluids and generated hydroxyl radicals in the presence of H2O2. Cell studies showed that GIT fluids incubation of Au NPs affected the cellular uptake of Au NPs but did not induce cytotoxicity or disturb the intestinal epithelial permeability. 相似文献
3.
4.
5.
Aaron Pitzele Mohammad Rahimi Eric Armbrecht 《The journal of maternal-fetal & neonatal medicine》2015,28(15):1770-1773
Objective: To determine whether packed red blood cell (PRBC) transfusion affects post-prandial superior mesenteric artery blood flow velocities (SMA BFVs) in very-low birth weight (VLBW) neonates and if so, at what time point after transfusion restoration of previous SMA BFV patterns occurs.Design/Methods: VLBW pre-term neonates, older than 14 days and tolerating bolus enteral feedings administered every 3?h were enrolled in this prospective observational study. Pulsed Doppler ultrasound was used to measure pre- and post-prandial (at 45?min) time-averaged mean, peak and end diastolic velocities (TAMV, PSV, EDV) immediately before and after 15?ml/kg of PRBC transfusion was given over 3?h; patent ductus arteriosus (PDA) status was also evaluated. Subsequent pre- and post-prandial SMA BFVs were recorded 24 and 48?h after the transfusion.Results: Pre- and post-prandial measurements were obtained for 21 out of 25 enrolled infants. Post-prandial SMA BFVs were attenuated during the feedings immediately after transfusion; at 24 and 48?h after transfusion, changes in post-prandial SMA BFVs were similar to those measured prior to transfusion; the presence of the PDA did not affect results.Conclusions: PRBC transfusion blunted SMA BFV responses to feedings immediately after the transfusion with normalization observed 24?h post-transfusion. 相似文献
6.
7.
8.
9.
《Gaceta sanitaria / S.E.S.P.A.S》2021,35(3):236-242
ObjectiveTo explore the views of the Internet in childhood, identifying both health assets and risks.MethodA qualitative study was performed using 14 focus groups, eight of which comprised boys and girls, four of which comprised parents and two of which were mixed (children and parents) in primary schools in urban and rural settings in Andalusia (Spain). Teachers in these schools were also asked to complete an online questionnaire using LimeSurvey. This study involved 114 individuals: 64 pupils (33 girls and 31 boys), 28 parents (18 mothers and 10 fathers), and 22 teachers (14 women and 8 men). Analysis of manifest content and underlying meanings was carried out. QSR NVivo 9 software was used to facilitate analysis and make it systematic.ResultsOur findings show how the differences in the way parents and children understand health and wellbeing affect the way they discuss the Internet and health. The discussion of results looks at the implications of computer literacy for public health and wellbeing, particularly with regard to health assets.ConclusionsParents and children understand the contribution of the Internet to health and wellbeing differently. Whilst parents emphasize the risks (unsafe environment, relationships and quality of information, social networks, physical problems and addiction), the children emphasize the assets offered by the Internet. 相似文献
10.