全文获取类型
收费全文 | 32200篇 |
免费 | 1876篇 |
国内免费 | 155篇 |
专业分类
耳鼻咽喉 | 321篇 |
儿科学 | 781篇 |
妇产科学 | 799篇 |
基础医学 | 4740篇 |
口腔科学 | 1884篇 |
临床医学 | 2717篇 |
内科学 | 7172篇 |
皮肤病学 | 981篇 |
神经病学 | 2796篇 |
特种医学 | 529篇 |
外科学 | 2591篇 |
综合类 | 128篇 |
一般理论 | 21篇 |
预防医学 | 3650篇 |
眼科学 | 523篇 |
药学 | 2554篇 |
中国医学 | 192篇 |
肿瘤学 | 1852篇 |
出版年
2024年 | 42篇 |
2023年 | 384篇 |
2022年 | 873篇 |
2021年 | 1534篇 |
2020年 | 868篇 |
2019年 | 1249篇 |
2018年 | 1515篇 |
2017年 | 1009篇 |
2016年 | 961篇 |
2015年 | 1196篇 |
2014年 | 1570篇 |
2013年 | 1934篇 |
2012年 | 2957篇 |
2011年 | 3117篇 |
2010年 | 1545篇 |
2009年 | 1298篇 |
2008年 | 2140篇 |
2007年 | 2078篇 |
2006年 | 1801篇 |
2005年 | 1579篇 |
2004年 | 1369篇 |
2003年 | 1150篇 |
2002年 | 999篇 |
2001年 | 108篇 |
2000年 | 62篇 |
1999年 | 92篇 |
1998年 | 134篇 |
1997年 | 128篇 |
1996年 | 82篇 |
1995年 | 64篇 |
1994年 | 66篇 |
1993年 | 48篇 |
1992年 | 44篇 |
1991年 | 29篇 |
1990年 | 23篇 |
1989年 | 20篇 |
1988年 | 16篇 |
1987年 | 14篇 |
1986年 | 13篇 |
1985年 | 12篇 |
1984年 | 12篇 |
1983年 | 12篇 |
1982年 | 15篇 |
1981年 | 9篇 |
1980年 | 13篇 |
1978年 | 6篇 |
1976年 | 6篇 |
1975年 | 7篇 |
1973年 | 5篇 |
1972年 | 5篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
Santos Marília Neves Azeredo Catarina Machado Rinaldi Ana Elisa Madalena 《Maternal and child health journal》2022,26(7):1496-1506
Maternal and Child Health Journal - The aim of this study was to estimate the association between individual and contextual characteristics related to maternal work and exclusive breastfeeding... 相似文献
82.
Daniel Gonzlez-Hedstrm Teresa Priego Asuncin Lpez-Caldern Sara Amor María de la Fuente-Fernndez Antonio Manuel Inarejos-García ngel Luis García-Villaln Ana Isabel Martín Miriam Granado 《Nutrients》2021,13(1)
Aging is associated with a progressive decline in skeletal muscle mass, strength and function (sarcopenia). We have investigated whether a mixture of algae oil (25%) and extra virgin olive oil (75%) could exert beneficial effects on sarcopenia. Young (3 months) and old (24 months) male Wistar rats were treated with vehicle or with the oil mixture (OM) (2.5 mL/kg) for 21 days. Aging decreased gastrocnemius weight, total protein, and myosin heavy chain mRNA. Treatment with the OM prevented these effects. Concomitantly, OM administration decreased the inflammatory state in muscle; it prevented the increase of pro-inflammatory interleukin-6 (IL-6) and the decrease in anti-inflammatory interleukin-10 (IL-10) in aged rats. The OM was not able to prevent aging-induced alterations in either the insulin-like growth factor I/protein kinase B (IGF-I/Akt) pathway or in the increased expression of atrogenes in the gastrocnemius. However, the OM prevented decreased autophagy activity (ratio protein 1A/1B-light chain 3 (LC3b) II/I) induced by aging and increased expression of factors related with muscle senescence such as histone deacetylase 4 (HDAC-4), myogenin, and IGF-I binding protein 5 (IGFBP-5). These data suggest that the beneficial effects of the OM on muscle can be secondary to its anti-inflammatory effect and to the normalization of HDAC-4 and myogenin levels, making this treatment an alternative therapeutic tool for sarcopenia. 相似文献
83.
Rosa M. García-García María Arias-lvarez Pilar Milln María Rodríguez Ana Snchez-Rodríguez Pedro L. Lorenzo Pilar G. Rebollar 《Nutrients》2021,13(2)
Nutritional status during gestation can influence mother and offspring metabolism. Undernutrition in pregnancy affects women in both western and developing countries, and it is associated with a high prevalence of chronic diseases in later life. The present work was conducted in the rabbit model, as a longitudinal study, to examine the effect of food restriction during early and mid-gestation, and re-feeding ad libitum until the end of pregnancy on metabolic status and body reserves of mother and, its association with development and metabolism of fetuses and female offspring to the juvenile stage. Little changes in live body weight (LBW), compensatory feed intake, similar body reserves, and metabolism were observed in dams. Placenta biometry and efficiency were slightly affected, but fetal BW and phenotype were not modified. However, hyperinsulinemia, insulin resistance, and hypertriglyceridemia were demonstrated in pre-term fetuses. In the juvenile period, these changes were not evidenced, and a similar pattern of growth and serum metabolic parameters in offspring of food-restricted mothers were found, except in serum aminotransferases levels, which increased. These were associated with higher liver fibrosis. Maternal food restriction in the early and mid-pregnancy followed by re-feeding in our rabbit model established a compensatory energy status in dams and alleviated potential long-term consequences in growth and metabolism in the offspring, even if fetal metabolism was altered. 相似文献
84.
Osvaldo Santos Miodraga Stefanovska-Petkovska Ana Virgolino Ana Cristina Miranda Joana Costa Elisabete Fernandes Susana Cardoso Antnio Vaz Carneiro 《Nutrients》2021,13(3)
Self-management of health requires skills to obtain, process, understand, and use health-related information. Assessment of adolescents’ functional health literacy requires valid, reliable, and low-burden tools. The main objective of this study was to adapt and study the psychometric properties of the Newest Vital Sign for the Portuguese adolescents’ population (NVS-PTeen). Classic psychometric indicators of reliability and validity were combined with item response theory (IRT) analyses in a cross-sectional survey, complemented with a 3-month test-retest assessment. The NVS-PTeen was self-administered to students enrolled in grades 8 to 12 (12 to 17 years old) in a school setting. Overall, 386 students (191 girls) from 16 classes of the same school participated in the study (mean age = 14.5; SD = 1.5). Internal reliability of the NVS-PTeen was α = 0.60. The NVS-PTeen total score was positively and significantly correlated with Portuguese (r = 0.28) and mathematics scores (r = 0.31), school years (r = 0.31), and age (r = 0.19). Similar to the original scale (for the U.S.), the NVS-PTeen is composed of two dimensions, reading-related literacy and numeracy. Temporal reliability is adequate, though with a learning effect. IRT analyses revealed differences in difficulty and discriminative capacity among items, all with adequate outfit and infit values. Results showed that the NVS-PTeen is valid and reliable, sensible to inter-individual educational differences, and adequate for regular screening of functional health literacy in adolescents. 相似文献
85.
Carla Fernandes Ana F. Santos Marilia Fernandes Antnio J. Santos Kelly Bost Manuela Verissimo 《Nutrients》2021,13(4)
Although there is a large body of research connecting emotion to eating behaviors, little is known about the role of caregivers’ responses to children’s emotions in the context of child feeding. The purpose of this study was to analyze the relation between caregivers’ emotional responsiveness and feeding responsiveness. The mothers of 137 children between 2 and 6 years of age reported on their responses to children’s negative emotions using the Coping with Children’s Negative Emotions Scale and on their feeding practices using the Comprehensive Feeding Practices Questionnaire. The results showed that mothers’ supportive emotion responses (e.g., problem-focused, emotion-focused, and expressive encouragement reactions) tend to be positively associated with responsive feeding practices (e.g., encouraging, modelling, and teaching healthy food-related behaviors). Instead, mothers’ unsupportive responses (e.g., distress, punitive and minimization reactions) tend to be positively associated with nonresponsive feeding practices (e.g., food as reward or to regulate emotions, and pressure to eat) and negatively associated with responsive feeding practices. Our results suggest that emotional and feeding responsiveness may be intertwined and that differences in parent’s emotional responsiveness may translate into differences in their feeding styles, setting the stage for parents’ use of positive vs. negative feeding practices. 相似文献
86.
Yasmin Amaral Leila Silva Fernanda Soares Daniele Marano Sylvia Nehab Andrea Abranches Ana Carolina Costa Maria Elisabeth Moreira 《Nutrients》2021,13(5)
Background: To evaluate the potential factors associated with the nutritional composition of human milk of puerperal women. Methods: cross-sectional study, conducted between March 2016 and August 2017, with 107 women, selected in a Tertiary Health Care Tertiary Health Facility of the Unified Health System (SUS) in the Municipality of Rio de Janeiro. Data were collected two months after delivery. The dependent variable of the study was the nutritional composition of human milk. We divided the independent variables into hierarchical levels: distal (age, schooling, parity and pregestational nutritional status), intermediate (number of prenatal visits and gestational weight gain) and proximal (alcohol consumption, smoking, diabetes mellitus and hypertension). For data analysis, we applied the multiple linear regression, centered on the hierarchical model. Only the variables associated with the nutritional composition of breast milk remained in the final model at a 5% level of significance. Results: The nutritional composition of human milk yielded by women with pregestational overweight, smokers and hypertensive had higher amounts of lipids and energy. Conversely, women with gestational weight gain below the recommended had lower amounts of these components. Conclusion: The evaluation of factors associated with the nutritional composition of human milk is extremely important to assist post-partum care practices. In this study, we observed that lipid and energy contents were associated to pregestational nutritional status, gestational weight gain, smoking and hypertension. 相似文献
87.
Ana Stupin Ines Drenjan
evi Petar unjara
eljko Debeljak Nikolina Kolobari Ivana Juki Zrinka Mihaljevi Goran Martinovi Kristina Selthofer-Relati 《Nutrients》2021,13(5)
This study aimed to test the effect of a 7-day high-salt (HS) diet on autonomic nervous system (ANS) activity in young healthy individuals and modulation of ANS on microvascular endothelial function impairment. 47 young healthy individuals took 7-day low-salt (LS) diet (3.5 g salt/day) followed by 7-day high-salt (HS) diet (~14.7 g salt/day). ANS activity was assessed by 24-h urine catecholamine excretion and 5-min heart rate variability (HRV). Skin post-occlusive reactive hyperemia (PORH) and acetylcholine-induced dilation (AChID) were assessed by laser Doppler flowmetry (LDF). Separately, mental stress test (MST) at LS and HS condition was conducted, followed by immediate measurement of plasma metanephrines’ level, 5-min HRV and LDF microvascular reactivity. Noradrenaline, metanephrine and normetanephrine level, low-frequency (LF) HRV and PORH and AChID significantly decreased following HS compared to LS. MST at HS condition tended to increase HRV LF/HF ratio. Spectral analysis of PORH signal, and AChID measurement showed that MST did not significantly affect impaired endothelium-dependent vasodilation due to HS loading. In this case, 7-day HS diet suppressed sympathetic nervous system (SNS) activity, and attenuated microvascular reactivity in salt-resistant normotensive individuals. Suppression of SNS during HS loading represents a physiological response, rather than direct pathophysiological mechanism by which HS diet affects microvascular endothelial function in young healthy individuals. 相似文献
88.
The association between obesity and vitamin A has been studied. Some studies point to the anti-obesity activity related to this vitamin, carotenoids with provitamin A activity, and carotenoid conversion products. This performance has been evaluated in respect of adipogenesis, metabolic activity, oxidation processes, secretory function, and oxidative stress modulation, showing a new property attributed to vitamin A in preventing and treating obesity. However, vitamin A and its precursors are highly sensitive and easily degraded when subjected to heat, the presence of light, and oxygen, in addition to losses related to the processes of digestion and absorption. In this context, encapsulation presents itself as an alternative capable of increasing vitamin A’s stability in the face of unfavorable conditions in the environment, which can reduce its functionality. Considering that vitamin A’s status shows a strong correlation with obesity and is an innovative theme, this article addresses the associations between vitamin A’s consumption and its precursors, encapsulated or not, and its physiological effects on obesity. The present narrative review points out those recent studies that demonstrate that vitamin A and its encapsulated precursors have the most preserved functionality, which guarantees better effects on obesity therapy. 相似文献
89.
Xavier Nogués Francisca Sánchez-Martinez Xavier Castells Adolfo Díez-Pérez Rosa Ana Sabaté Irene Petit Ariadna Brasé Juan Pablo Horcajada Roberto Güerri-Fernández Julio Pascual 《Journal of the American Medical Directors Association》2021,22(5):939-942
A Coronavirus Disease 2019 (COVID-19)–specific Hospital-at-Home was implemented in a 400-bed tertiary hospital in Barcelona, Spain. Senior or immune-compromised physicians oversaw patient care. The alternative to inpatient care more than doubled beds available for hospitalization and decreased the risk of transmission among patients and health care professionals. Mild cases from either the emergency department or after hospital discharge were deemed suitable for admission to the Hospital-at-Home. More than half of all patients had pneumonia. Standardized protocols and management criteria were provided. Only 6% of cases required referral for inpatient hospitalization. These results are promising and may provide valuable insight for centers undertaking Hospital-at-Home initiatives or in the case of new COVID-19 outbreaks. 相似文献
90.
Daniel Wei Liang Wang Gabriela Moribe Ana Luiza Gajardoni De M. Arruda 《Health and human rights》2021,23(1):163
Mandatory vaccination for COVID-19 has been the object of heated debate in Brazil. This article discusses the legality and constitutionality of such a policy. First, it analyzes the laws, regulations, and Supreme Court decisions that provide for the possibility of mandatory COVID-19 vaccination. Subsequently, it analyzes the constitutionality of a mandatory vaccination policy through the proportionality method to address the conflict between, on one side, the right to individual autonomy, which includes the right to refuse a medical intervention, and, on the other, health policies that interfere with individual autonomy to protect the rights to life and health. The application of this method allows for the identification of key questions that need to be answered to determine the constitutionality of a mandatory vaccination program. These questions cannot be answered a priori and in the abstract because they depend on the concrete circumstances of the pandemic, on the characteristics of the vaccine(s) against COVID-19, and on how a mandatory vaccination policy might be designed and implemented by authorities. 相似文献