全文获取类型
收费全文 | 176006篇 |
免费 | 13477篇 |
国内免费 | 2327篇 |
专业分类
耳鼻咽喉 | 782篇 |
儿科学 | 4551篇 |
妇产科学 | 3069篇 |
基础医学 | 12950篇 |
口腔科学 | 3265篇 |
临床医学 | 34632篇 |
内科学 | 20463篇 |
皮肤病学 | 1293篇 |
神经病学 | 13113篇 |
特种医学 | 3038篇 |
外国民族医学 | 2篇 |
外科学 | 12110篇 |
综合类 | 19411篇 |
现状与发展 | 7篇 |
一般理论 | 69篇 |
预防医学 | 38748篇 |
眼科学 | 1146篇 |
药学 | 14142篇 |
227篇 | |
中国医学 | 3463篇 |
肿瘤学 | 5329篇 |
出版年
2024年 | 381篇 |
2023年 | 4153篇 |
2022年 | 5728篇 |
2021年 | 8511篇 |
2020年 | 8506篇 |
2019年 | 8757篇 |
2018年 | 8115篇 |
2017年 | 6871篇 |
2016年 | 6236篇 |
2015年 | 6258篇 |
2014年 | 12553篇 |
2013年 | 13511篇 |
2012年 | 10569篇 |
2011年 | 11235篇 |
2010年 | 8622篇 |
2009年 | 8375篇 |
2008年 | 8162篇 |
2007年 | 7966篇 |
2006年 | 6787篇 |
2005年 | 5484篇 |
2004年 | 4534篇 |
2003年 | 3744篇 |
2002年 | 2933篇 |
2001年 | 2570篇 |
2000年 | 2195篇 |
1999年 | 1890篇 |
1998年 | 1699篇 |
1997年 | 1492篇 |
1996年 | 1237篇 |
1995年 | 1082篇 |
1994年 | 1029篇 |
1993年 | 903篇 |
1992年 | 787篇 |
1991年 | 730篇 |
1990年 | 608篇 |
1989年 | 517篇 |
1988年 | 509篇 |
1987年 | 485篇 |
1986年 | 429篇 |
1985年 | 803篇 |
1984年 | 827篇 |
1983年 | 583篇 |
1982年 | 613篇 |
1981年 | 574篇 |
1980年 | 497篇 |
1979年 | 395篇 |
1978年 | 348篇 |
1977年 | 282篇 |
1976年 | 230篇 |
1975年 | 163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.
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.
《Health & place》2022
Whose values matter when considering which environment is healthier for a child whose guardianship is contested? The biological mother from a remote Australian Aboriginal community, who voluntarily relinquished her but has now requested her return? The foster mother who has cared for her in a metropolitan centre in another State of Australia, thousands of kilometres away? The welfare professionals who also live in that city? Or the child herself, who left her birth home and community five years earlier at the age of two? Drawing on a case study of a seven-year old Aboriginal girl, the authors argue that non-Indigenous values trumped Indigenous values without the realisation of key players who were empowered to make such determinations. The article uses Manuel DeLanda's neo-assemblage theory to consider the range of processes that exert themselves to shape place-values and social identity in colonised nations. It will also draw on Erik Erikson's and Lev Vygotsky's theories of psychosocial development to consider competing sets of values that raised feelings of dissonance within the child. Beliefs about what makes a place health-giving are revealed to be complex in colonised nations. Despite policy and legislative changes to better support Aboriginal people and their right to difference, non-Indigenous professionals can continue to be driven by an unrecognised systemic racism. While place-values are not, of course, the only (or perhaps even the most significant) consideration in guardianship determinations, this article will argue they can play a significant and covert role. 相似文献
7.
8.
《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
9.
ObjectivesOsteopathy is regulated as an independent healthcare profession in Portugal. The Osteopathic Practitioners Estimates and RAtes (OPERA) project was developed as a survey to profile the osteopathic profession. This study aimed to describe the characteristics of Portuguese osteopathic practitioners.MethodsA voluntary online-based survey was distributed across Portugal between February and June 2020. The survey, composed of 52 questions and seven sections, was formally translated from English to Portuguese and adapted from the original version. Two pilot tests evaluated cultural adaptation and reproducibility. Adult, self-defined osteopaths working in Portugal were eligible. Recruitment of participants was performed through social media and an e-based campaign.ResultsA total of 222 osteopaths participated in the study, 143 were male (64%), aging between 30 and 39 years (42%), mainly working in Lisbon (30%). Most respondents had preliminary healthcare training (68%), mainly as massage therapists. The majority of respondents were self-employed (83%), owner of a clinic (55%) and working alone (59%). The median number of consultations per week was 21–25 and respondents scheduled 46–60 min for each consultation. The majority of patients seek care for lumbar (52%), cervical (38%) and upper spine (38%) complaints. Although most respondents experience a strong osteopathic identity, they do not advertise themselves exclusively as osteopaths.ConclusionsThis study represents the first nationwide document to determine osteopaths' characteristics in Portugal. The study results provide a basis for future surveys that will include cohorts with higher levels of education, as well as findings from other European countries. 相似文献
10.
The circadian rhythm in humans is determined by the central clock located in the hypothalamus’s suprachiasmatic nucleus, and it synchronizes the peripheral clocks in other tissues. Circadian clock genes and clock-controlled genes exist in almost all cell types. They have an essential role in many physiological processes, including lipid metabolism in the liver, regulation of the immune system, and the severity of infections. In addition, circadian rhythm genes can stimulate the immune response of host cells to virus infection. Hepatitis B virus (HBV) infection is the leading cause of liver disease and liver cancer globally. HBV infection depends on the host cell, and hepatocyte circadian rhythm genes are associated with HBV replication, survival, and spread. The core circadian rhythm proteins, REV-ERB and brain and muscle ARNTL-like protein 1, have a crucial role in HBV replication in hepatocytes. In addition to influencing the virus’s life cycle, the circadian rhythm also affects the pharmacokinetics and efficacy of antiviral vaccines. Therefore, it is vital to apply antiviral therapy at the appropriate time of day to reduce toxicity and improve the effectiveness of antiviral treatment. For these reasons, understanding the role of the circadian rhythm in the regulation of HBV infection and host responses to the virus provides us with a new perspective of the interplay of the circadian rhythm and anti-HBV therapy. Therefore, this review emphasizes the importance of the circadian rhythm in HBV infection and the optimization of antiviral treatment based on the circadian rhythm-dependent immune response. 相似文献