全文获取类型
收费全文 | 43481篇 |
免费 | 4630篇 |
国内免费 | 875篇 |
专业分类
耳鼻咽喉 | 308篇 |
儿科学 | 927篇 |
妇产科学 | 569篇 |
基础医学 | 3257篇 |
口腔科学 | 1507篇 |
临床医学 | 4162篇 |
内科学 | 5693篇 |
皮肤病学 | 474篇 |
神经病学 | 3369篇 |
特种医学 | 1266篇 |
外国民族医学 | 3篇 |
外科学 | 3588篇 |
综合类 | 4812篇 |
现状与发展 | 5篇 |
一般理论 | 2篇 |
预防医学 | 7586篇 |
眼科学 | 575篇 |
药学 | 3323篇 |
25篇 | |
中国医学 | 4418篇 |
肿瘤学 | 3117篇 |
出版年
2024年 | 93篇 |
2023年 | 982篇 |
2022年 | 1030篇 |
2021年 | 1894篇 |
2020年 | 1821篇 |
2019年 | 1812篇 |
2018年 | 1826篇 |
2017年 | 1688篇 |
2016年 | 1515篇 |
2015年 | 1350篇 |
2014年 | 3190篇 |
2013年 | 3220篇 |
2012年 | 2558篇 |
2011年 | 2721篇 |
2010年 | 2077篇 |
2009年 | 2000篇 |
2008年 | 2273篇 |
2007年 | 2321篇 |
2006年 | 2087篇 |
2005年 | 1730篇 |
2004年 | 1424篇 |
2003年 | 1348篇 |
2002年 | 1041篇 |
2001年 | 976篇 |
2000年 | 777篇 |
1999年 | 668篇 |
1998年 | 485篇 |
1997年 | 520篇 |
1996年 | 398篇 |
1995年 | 417篇 |
1994年 | 358篇 |
1993年 | 299篇 |
1992年 | 299篇 |
1991年 | 262篇 |
1990年 | 221篇 |
1989年 | 209篇 |
1988年 | 197篇 |
1987年 | 157篇 |
1986年 | 126篇 |
1985年 | 116篇 |
1984年 | 100篇 |
1983年 | 67篇 |
1982年 | 65篇 |
1981年 | 61篇 |
1980年 | 57篇 |
1979年 | 32篇 |
1978年 | 29篇 |
1977年 | 26篇 |
1976年 | 18篇 |
1975年 | 18篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
《Health & place》2022
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.
3.
Virginija Pokut Rta Kazlauskait Irmina Matonyt 《Health & social care in the community》2022,30(1):193-202
Demographic situation, changes in the role of women in society and growing demand for long-term care (LTC) of older people have challenged the ability to meet the growing LTC needs in most developed countries. In countries where responsibility for LTC is still largely laid on families, it is, however, even more critical and calls for improvements in formal LTC systems. More intensive stakeholder collaboration in LTC policy development, organising and delivery are of primary importance in improving LTC systems. Such collaboration, however, is not always successful; thus, it is critical to understand what makes it effective and efficient. In this paper, we specifically look into multistakeholder collaboration in LTC in Lithuania, one of the fastest ageing countries in the EU, with the demand for LTC services growing fast and exceeding the supply despite rising business and NGO engagement. To determine facilitators of such collaboration, we build on the data obtained through eight focus group discussions with all key stakeholder representatives (LTC policymakers, organisers and service providers [public, private and NGOs], 54 participants in total). Our findings indicate that in addition to national and organisational level facilitators studied in prior research, there are important individual level factors, such as meaningfulness at work, concern and care for others, possibility for personal growth and development, satisfaction with supervision, a sense of belonging and role clarity. On the other hand, our results show that collaboration is constrained by a shortage of human resources, increased workload caused by growing LTC demand, bureaucratic requirements, legal restrictions, lack of awareness of LTC service availability among elder persons, and prevailing social norms and attitudes to institutionalised care. Interestingly, a lack of financial resources is not perceived as a major constraint. 相似文献
4.
5.
《Vaccine》2016,34(15):1773-1777
BackgroundThere are conflicting findings regarding the impact of residential mobility on immunisation status. Our aim was to determine whether there was any association between residential mobility and take up of immunisations and whether they were delayed in administration.MethodsWe carried out a cohort analysis of children born in Wales, UK. Uptake and time of immunisation were collected electronically. We defined frequent movers as those who had moved: 2 or more times in the period prior to the final scheduled on-time date (4 months) for 5 in 1 vaccinations; and 3 or more times in the period prior to the final scheduled on-time date (12 months) for MMR, pneumococcal and meningitis C vaccinations. We defined immunisations due at 2–4 months delayed if they had not been given by age 1; and those due at 12–13 months as delayed if they had not been given by age 2.ResultsUptake rates of routine immunisations and whether they were given within the specified timeframe were high for both groups. There was no increased risk (odds ratios (95% confidence intervals) between frequent movers compared to non-movers for the uptake of: primary MMR 1.08 (0.88–1.32); booster Meningitis C 1.65 (0.93–2.92); booster pneumococcal 1.60 (0.59–4.31); primary 5 in 1 1.28 (0.92–1.78); and timeliness: primary MMR 0.92 (0.79–1.07); booster Meningitis C 1.26 (0.77–2.07); booster pneumococcal 1.69 (0.23–12.14); and primary 5 in 1 1.04 (0.88–1.23).DiscussionFindings suggest that children who move home frequently are not adversely affected in terms of the uptake of immunisations and whether they were given within a specified timeframe. Both were high and may reflect proactive behaviour in the primary healthcare setting to meet Government coverage rates for immunisation. 相似文献
6.
This study is focussed on micro-encapsulation of essential oils in polylactic acid (PLA) and a poly(methyl methacrylate) (PMMA) matrix as well as blends of the same. Microspheres were prepared by the solvent evaporation technique and characterised by scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and Fourier transform infra-red spectroscopy (FTIR). The encapsulation efficiencies and release profiles of the essential oils were studied by gas chromatography mass spectrometry (GC-MS) and head-space solid-phase microextraction GC-MS, respectively. Furthermore, the microspheres were tested for antibacterial activity against both Gram-negative and Gram-positive bacterial strains.
The results showed that the microspheres compositions (PLA/PMMA ratio) have significant effect on their characteristics. The process adopted for preparing the microspheres promoted formation of spherical particles at the sizes of 1.5–9.5?µm. The highest encapsulation efficiency of the prepared microspheres was observed in systems consisting of linalool (81.10?±?10.0?wt. % for PLA system and 76.0?±?3.3?wt. % for PMMA system). Confirmation was also made that the release rate of the microspheres was affected by the size of the same. 相似文献
7.
8.
Samir Gupta MD MDCS AGAF Balambal Bharti MBBS MPH PhD Dennis J. Ahnen MD Daniel D. Buchanan PhD Iona C. Cheng PhD MPH Michelle Cotterchio PhD Jane C. Figueiredo PhD Steven J. Gallinger MD MSc Robert W. Haile DrPH MPH Mark A. Jenkins PhD Noralane M. Lindor MD Finlay A. Macrae MD AGAF Loïc Le Marchand MD PhD Polly A. Newcomb PhD MPH Stephen N. Thibodeau PhD Aung Ko Win MBBS MPH PhD Maria Elena Martinez PhD 《Cancer》2020,126(13):3013-3020
9.
Azadeh Badie Kioomars Saliminejad Iman Salahshourifar 《Gynecological endocrinology》2020,36(2):135-138
AbstractEndometriosis is one of the most common gynecological diseases and a major cause of pain and infertility. It is influenced by genetic, epigenetic, and environmental factors. Recently, genome-wide association studies have revealed a strong association between IL1A single nucleotide polymorphisms (SNPs) and increased risk of endometriosis in Japanese women. The aim of the present study was to evaluate the association of three IL1A SNPs, rs17561, rs1304037, and rs2856836 with the risk of endometriosis in Iranian population. Totally, 105 women with diagnosis of endometriosis and 102 healthy women as control group were included. Three SNPs of the IL1A, rs17561?G/T, rs1304037 A/G, and rs2856836 T/C, were genotyped by PCR and RFLP. The rs2856836?TC genotype was significantly higher (p?=?.002; OR?=?3.1, 95% CI: 1.5–6.5) in the patients (28.1%) than the control group (12.7%). The rs2856836?CC genotype was significantly higher (p?=?.047; OR?=?2.3, 95% CI: 1.0–5.3) in the patients (17.5%) than the control group (10.8%). The rs2856836 C allele was significantly higher (p?=?.001; OR?=?2.2, 95% CI: 1.4–3.6) in the patients (31.6%) than the control group (17.2%). The IL1A rs2856836 T/C SNP was associated with susceptibility to endometriosis and the rs2856836 C allele may increase the risk of endometriosis in Iranian women. 相似文献
10.