全文获取类型
收费全文 | 102958篇 |
免费 | 10086篇 |
国内免费 | 746篇 |
专业分类
耳鼻咽喉 | 328篇 |
儿科学 | 2176篇 |
妇产科学 | 1845篇 |
基础医学 | 6109篇 |
口腔科学 | 4689篇 |
临床医学 | 18695篇 |
内科学 | 9034篇 |
皮肤病学 | 697篇 |
神经病学 | 5784篇 |
特种医学 | 1103篇 |
外科学 | 4429篇 |
综合类 | 9870篇 |
现状与发展 | 4篇 |
一般理论 | 94篇 |
预防医学 | 39492篇 |
眼科学 | 472篇 |
药学 | 5377篇 |
102篇 | |
中国医学 | 1245篇 |
肿瘤学 | 2245篇 |
出版年
2024年 | 405篇 |
2023年 | 3041篇 |
2022年 | 3979篇 |
2021年 | 5530篇 |
2020年 | 5718篇 |
2019年 | 5504篇 |
2018年 | 4816篇 |
2017年 | 4469篇 |
2016年 | 4257篇 |
2015年 | 4199篇 |
2014年 | 6727篇 |
2013年 | 9142篇 |
2012年 | 5888篇 |
2011年 | 6411篇 |
2010年 | 4865篇 |
2009年 | 4932篇 |
2008年 | 4777篇 |
2007年 | 4735篇 |
2006年 | 4097篇 |
2005年 | 3198篇 |
2004年 | 2794篇 |
2003年 | 2394篇 |
2002年 | 1809篇 |
2001年 | 1688篇 |
2000年 | 1460篇 |
1999年 | 1066篇 |
1998年 | 918篇 |
1997年 | 708篇 |
1996年 | 626篇 |
1995年 | 443篇 |
1994年 | 396篇 |
1993年 | 369篇 |
1992年 | 320篇 |
1991年 | 279篇 |
1990年 | 252篇 |
1989年 | 172篇 |
1988年 | 207篇 |
1987年 | 141篇 |
1986年 | 135篇 |
1985年 | 165篇 |
1984年 | 134篇 |
1983年 | 84篇 |
1982年 | 74篇 |
1981年 | 74篇 |
1980年 | 74篇 |
1979年 | 59篇 |
1978年 | 51篇 |
1977年 | 57篇 |
1976年 | 44篇 |
1975年 | 38篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Objective
The aim of the study was to estimate the effect of the state-based reinsurance programs through the section 1332 State Innovation Waivers on health insurance marketplace premiums and insurer participation.Data Source
2015 to 2022 Robert Wood Johnson Foundation Health Insurance Exchange Compare Datasets.Study Design
An event study difference-in-differences (DD) model separately for each year of implementation and a synthetic control method (SCM) are used to estimate year-by-year effects following program implementation.Data Collection/Extraction Methods
Not applicable.Principal Findings
Reinsurance programs were associated with a decline in premiums in the first year of implementation by 10%–13%, 5%–19%, and 11%–17% for bronze, silver, and gold plans (p < 0.05). There is a trend of sustained declines especially for states that implemented their programs in 2019 and 2020. The SCM analyses suggest some effect heterogeneity across states but also premium declines across most states. There is no evidence that reinsurance programs affected insurer participation.Conclusion
State-based reinsurance programs have the potential to improve the affordability of health insurance coverage. However, reinsurance programs do not appear to have had an effect on insurer participation, highlighting the need for policy makers to consider complementary strategies to encourage insurer participation. 相似文献2.
3.
4.
《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
5.
6.
《The Journal for Nurse Practitioners》2022,18(4):372-376
The effects of climate change include floods, hurricanes, heat waves, and fires; these natural disasters can result in respiratory, cardiovascular, and psychological harm in older adults, who experience the highest morbidity and mortality during heat waves. Advanced practice registered nurses (APRNs) need education on preparing, assessing, and treating older adults for climate-change disasters, especially heat waves. This article will help APRNs understand the effects of climate-change events on the vulnerable older adults and advocates for the need to integrate health effects of climate change into curricula, practicums, policy, and research agendas. 相似文献
7.
《Journal of pediatric surgery》2023,58(9):1613-1617
BackgroundThe goal of this study was to characterize contemporary performance benchmarks and risk factors associated with negative appendectomy (NA) in children with suspected appendicitis.MethodsA multicenter retrospective cohort analysis of children undergoing appendectomy for suspected appendicitis was performed using data from the 2016–2021 NSQIP-Pediatric Appendectomy Targeted Public Use Files. Multivariable regression was used to evaluate the influence of year, age, sex, and WBC count on NA rate, and to generate rate estimates for NA based on different combinations of demographic characteristics and WBC profiles.Results100,322 patients were included from 140 hospitals. The overall NA rate was 2.4%, and rates decreased significantly during the study period (2016: 3.1% vs. 2021: 2.3%, p < 0.001). In adjusted analyses, the highest risk for NA was associated with a normal WBC (<9000/mm3; OR 5.31 [95% CI: 4.87–5.80]), followed by female sex (OR 1.55 [95% CI: 1.42–1.68]) and age <5 years (OR 1.64 [95% CI 1.39, 1.94]). Model-estimated risk for NA varied significantly across demographic and WBC strata, with a 14.4-fold range in rates between subgroups with the lowest and highest predicted risk (males 13–17 years with elevated WBC [1.1%] vs. females 3–4 years with normal WBC [15.8%]).ConclusionsContemporary NA rates have decreased over time, however NA risk remains high in children without a leukocytosis, particularly for girls and children <5 years of age. These data provide contemporary performance benchmarks for NA in children with suspected appendicitis and identify high-risk populations where further efforts to mitigate NA risk should be targeted.Level of EvidenceIII. 相似文献
8.
9.
Child benefits are typically paid from birth. This paper asks whether starting universal child benefits in pregnancy leads to improvements in infant health. Leveraging administrative birth registry and hospital microdata from England and Wales, I study the effects of the Health in Pregnancy Grant, a universal conditional cash transfer equivalent to three months of child benefit (190 GBP) as a lump sum to pregnant mothers from 2009 to 2011. I exploit quasi-experimental variation in eligibility with a regression discontinuity design in the date of birth of the baby. I find that the policy increased birth weight by 8–12 grams on average, reduced low birth weight (2500 g) by 3-6 percent and decreased prematurity by 9–11 percent. Younger mothers, particularly those living in deprived areas, benefit the most. I present evidence that the mechanisms are unlikely to be antenatal care, nutrition or smoking, with reductions in stress remaining a possible explanation. 相似文献
10.