全文获取类型
收费全文 | 1879篇 |
免费 | 126篇 |
国内免费 | 16篇 |
专业分类
耳鼻咽喉 | 25篇 |
儿科学 | 51篇 |
妇产科学 | 51篇 |
基础医学 | 230篇 |
口腔科学 | 51篇 |
临床医学 | 117篇 |
内科学 | 491篇 |
皮肤病学 | 36篇 |
神经病学 | 182篇 |
特种医学 | 16篇 |
外科学 | 333篇 |
综合类 | 12篇 |
预防医学 | 134篇 |
眼科学 | 27篇 |
药学 | 121篇 |
中国医学 | 22篇 |
肿瘤学 | 122篇 |
出版年
2023年 | 10篇 |
2022年 | 15篇 |
2021年 | 39篇 |
2020年 | 32篇 |
2019年 | 39篇 |
2018年 | 61篇 |
2017年 | 34篇 |
2016年 | 48篇 |
2015年 | 64篇 |
2014年 | 82篇 |
2013年 | 85篇 |
2012年 | 131篇 |
2011年 | 154篇 |
2010年 | 98篇 |
2009年 | 83篇 |
2008年 | 122篇 |
2007年 | 157篇 |
2006年 | 118篇 |
2005年 | 114篇 |
2004年 | 134篇 |
2003年 | 105篇 |
2002年 | 99篇 |
2001年 | 11篇 |
2000年 | 9篇 |
1999年 | 16篇 |
1998年 | 17篇 |
1997年 | 9篇 |
1996年 | 6篇 |
1995年 | 17篇 |
1994年 | 8篇 |
1993年 | 4篇 |
1991年 | 5篇 |
1989年 | 4篇 |
1988年 | 3篇 |
1986年 | 5篇 |
1985年 | 3篇 |
1984年 | 5篇 |
1983年 | 5篇 |
1982年 | 3篇 |
1981年 | 5篇 |
1979年 | 7篇 |
1978年 | 6篇 |
1977年 | 6篇 |
1976年 | 3篇 |
1975年 | 6篇 |
1974年 | 4篇 |
1972年 | 3篇 |
1963年 | 4篇 |
1962年 | 3篇 |
1958年 | 3篇 |
排序方式: 共有2021条查询结果,搜索用时 15 毫秒
1.
2.
Paula C. Salamone Agustina Legaz Lucas Sedeo Sebastin Moguilner Matías Fraile-Vazquez Cecilia Gonzalez Campo Sol Fittipaldi Adrin Yoris Magdalena Miranda Agustina Birba Agostina Galiani Sofía Abrevaya Alejandra Neely Miguel Martorell Caro Florencia Alifano Roque Villagra Florencia Anunziata Maira Okada de Oliveira Ricardo M. Pautassi Andrea Slachevsky Cecilia Serrano Adolfo M. García Agustín Ibaez 《The Journal of neuroscience》2021,41(19):4276
Recent frameworks in cognitive neuroscience and behavioral neurology underscore interoceptive priors as core modulators of negative emotions. However, the field lacks experimental designs manipulating the priming of emotions via interoception and exploring their multimodal signatures in neurodegenerative models. Here, we designed a novel task that involves interoceptive and control-exteroceptive priming conditions followed by post-interoception and post-exteroception facial emotion recognition (FER). We recruited 114 participants, including healthy controls (HCs) as well as patients with behavioral variant frontotemporal dementia (bvFTD), Parkinson''s disease (PD), and Alzheimer''s disease (AD). We measured online EEG modulations of the heart-evoked potential (HEP), and associations with both brain structural and resting-state functional connectivity patterns. Behaviorally, post-interoception negative FER was enhanced in HCs but selectively disrupted in bvFTD and PD, with AD presenting generalized disruptions across emotion types. Only bvFTD presented impaired interoceptive accuracy. Increased HEP modulations during post-interoception negative FER was observed in HCs and AD, but not in bvFTD or PD patients. Across all groups, post-interoception negative FER correlated with the volume of the insula and the ACC. Also, negative FER was associated with functional connectivity along the (a) salience network in the post-interoception condition, and along the (b) executive network in the post-exteroception condition. These patterns were selectively disrupted in bvFTD (a) and PD (b), respectively. Our approach underscores the multidimensional impact of interoception on emotion, while revealing a specific pathophysiological marker of bvFTD. These findings inform a promising theoretical and clinical agenda in the fields of nteroception, emotion, allostasis, and neurodegeneration.SIGNIFICANCE STATEMENT We examined whether and how emotions are primed by interoceptive states combining multimodal measures in healthy controls and neurodegenerative models. In controls, negative emotion recognition and ongoing HEP modulations were increased after interoception. These patterns were selectively disrupted in patients with atrophy across key interoceptive-emotional regions (e.g., the insula and the cingulate in frontotemporal dementia, frontostriatal networks in Parkinson''s disease), whereas persons with Alzheimer''s disease presented generalized emotional processing abnormalities with preserved interoceptive mechanisms. The integration of both domains was associated with the volume and connectivity (salience network) of canonical interoceptive-emotional hubs, critically involving the insula and the anterior cingulate. Our study reveals multimodal markers of interoceptive-emotional priming, laying the groundwork for new agendas in cognitive neuroscience and behavioral neurology. 相似文献
3.
ABSTRACT Objective: To examine the relationship between race and smoking behaviors among Latinos/Hispanics. Design: Using data from the National Adult Tobacco Survey (NATS), we implemented Log-Poisson regression models for each dependent variable (smoking pattern and menthol cigarette use). Each analysis adjusted for age, gender, marital status, employment status, and socioeconomic status (SES). Final pooled cross-sectional sample included 505 Black-Latinos and 9078 White-Latinos. Results: While no racial differences were found in lifetime smoking status among Latinos, Black-Latinos had a 16.6% (95% CI: 0.274, 0.057) increased risk of menthol smoking compared to White-Latinos. Conclusions: The results indicate that menthol consumption is influenced by race among Hispanics/Latinos. To comprehensively address racial disparities among Latinos/Hispanics, further attention needs to be given to racial differences in smoking-related risks among Latinos/Hispanics. 相似文献
4.
5.
6.
Dunia Alarkawi M Sanni Ali Dana Bliuc Natalia Pallares Cristian Tebe Leena Elhussein Fergus J Caskey Nigel K Arden Yoav Ben-Shlomo Bo Abrahamsen Adolfo Diez-Perez Julio Pascual María José Pérez-Sáez Jacqueline R Center Andrew Judge Cyrus Cooper Muhammad K Javaid Daniel Prieto-Alhambra 《Journal of bone and mineral research》2020,35(5):894-900
7.
Are the High Hip Fracture Rates Among Norwegian Women Explained by Impaired Bone Material Properties? 下载免费PDF全文
Daysi Duarte Sosa Laila Vilaplana Roberto Güerri Xavier Nogués Morten Wang‐Fagerland Adolfo Diez‐Perez Erik F Eriksen 《Journal of bone and mineral research》2015,30(10):1784-1789
Hip fracture rates in Norway rank among the highest in the world, more than double that of Spanish women. Previous studies were unable to demonstrate significant differences between the two populations with respect to bone mass or calcium metabolism. In order to test whether the difference in fracture propensity between both populations could be explained by differences in bone material quality we assessed bone material strength using microindentation in 42 Norwegian and 46 Spanish women with normal BMD values, without clinical or morphometric vertebral fractures, no clinical or laboratory signs of secondary osteoporosis, and without use of drugs with known influence on bone metabolism. Bone material properties were assessed by microindentation of the thick cortex of the mid tibia following local anesthesia of the area using the Osteoprobe device (Active Life Scientific, Santa Barbara, CA, USA). Indentation distance was standardized against a calibration phantom of methylmethacrylate and results, as percentage of this reference value, expressed as bone material strength index units (BMSi). We found that the bone material properties reflected in the BMSi value of Norwegian women was significantly inferior when compared to Spanish women (77 ± 7.1 versus 80.7 ± 7.8, p < 0.001). Total hip BMD was significantly higher in Norwegian women (1.218 g/cm2 versus 0.938 g/cm2, p < 0.001) but regression analysis revealed that indentation values did not vary with BMD r2 = 0.03 or age r2 = 0.04. In conclusion Norwegian women show impaired bone material properties, higher bone mass, and were taller than Spanish women. The increased height will increase the impact on bone after falls, and impaired bone material properties may further enhance the risk fracture after such falls. These ethnic differences in bone material properties may partly explain the higher propensity for fracture in Norwegian women. © 2015 American Society for Bone and Mineral Research. 相似文献
8.
Bone Tissue Properties Measurement by Reference Point Indentation in Glucocorticoid‐Induced Osteoporosis 下载免费PDF全文
Fernando Mellibovsky Roberto Güerri‐Fernández Xavier Nogués Connor Randall Paul K Hansma Adolfo Díez‐Perez 《Journal of bone and mineral research》2015,30(9):1651-1656
Glucocorticoids, widely used in inflammatory disorders, rapidly increase bone fragility and, therefore, fracture risk. However, common bone densitometry measurements are not sensitive enough to detect these changes. Moreover, densitometry only partially recognizes treatment‐induced fracture reductions in osteoporosis. Here, we tested whether the reference point indentation technique could detect bone tissue property changes early after glucocorticoid treatment initiation. After initial laboratory and bone density measurements, patients were allocated into groups receiving calcium + vitamin D (Ca+D) supplements or anti‐osteoporotic drugs (risedronate, denosumab, teriparatide). Reference point indentation was performed on the cortical bone layer of the tibia by a handheld device measuring bone material strength index (BMSi). Bone mineral density was measured by dual‐energy X‐ray absorptiometry (DXA). Although Ca+D‐treated patients exhibited substantial and significant deterioration, risedronate‐treated patients exhibited no significant change, and both denosumab‐ and teriparatide‐treated participants exhibited significantly improved BMSi 7 weeks after initial treatment compared with baseline; these trends remained stable for 20 weeks. In contrast, no densitometry changes were observed during this study period. In conclusion, our study is the first to our knowledge to demonstrate that reference point indentation is sensitive enough to reflect changes in cortical bone indentation after treatment with osteoporosis therapies in patients newly exposed to glucocorticoids. © 2015 American Society for Bone and Mineral Research. 相似文献
9.
Prevalence of periodontopathic bacteria in aggressive periodontitis patients in a Chilean population 总被引:3,自引:0,他引:3
Gajardo M Silva N Gómez L León R Parra B Contreras A Gamonal J 《Journal of periodontology》2005,76(2):289-294
BACKGROUND: Actinobacillus actinomycetemcomitans is considered a major etiologic agent of aggressive periodontitis (AgP). Other periodontopathic bacteria such as Porphyromonas gingivalis are also suspected of participating in aggressive periodontitis although the evidence to support this is controversial. The aim of the present study was to determine the prevalence of eight periodontopathic bacteria in Chilean patients with AgP. METHODS: Subgingival plaque samples were collected from 36 aggressive, 30 localized, and six generalized periodontitis patients. Samples from 17 advanced chronic periodontitis (CP) patients were taken as controls. Samples collected from the four deepest periodontal pockets in each patient were pooled in prereduced transport fluid (RTF) and cultured. Periodontal bacteria were primarily identified by colony morphology under stereoscopic microscope and rapid biochemical tests. The identity of some bacterial isolates was confirmed by colony polymerase chain reaction (PCR). RESULTS: AgP showed a significatively higher prevalence of C. rectus than CP (P = 0.036). The only statistical difference found was for C. rectus. Patients with AgP showed a higher, but not statistically significant, prevalence of P. gingivalis, E. corrodens, P. micros, and Capnocytophaga sp. A similar prevalence in both groups of patients was observed for F. nucleatum and P. intermedia/nigrescens, and A. actinomycetemcomitans was less prevalent in AgP than CP patients. In localized AgP, P. intermedia/nigrescens, E. corrodens, F. nucleatum, and P. micros were the more prevalent pathogens in contrast to generalized AgP patients who harbored A. actinomycetemcomitans, P. gingivalis, and Capnocytophaga sp. as the most prevalent bacteria. CONCLUSIONS: C. rectus, P. gingivalis, E. corrodens, P. micros, and Capnocytophaga sp. were the most predominant periodontopathic bacteria of AgP in this Chilean population, but the only statistical difference found here between AgP and CP was for C. rectus, suggesting that the differences in clinical appearance may be caused by factors other than the microbiological composition of the subgingival plaque of these patients. In this study, the prevalence of A. actinomycetemcomitans was much lower than that of P. gingivalis. 相似文献
10.
Orlas Claudia P. Herrera-Escobar Juan Pablo Zogg Cheryl K. Serna José J. Meléndez Juan J. Gómez Alexandra Martínez Diana Parra Michael W. García Alberto F. Rosso Fernando Pino Luis Fernando Gonzalez Adolfo Ordoñez Carlos A. 《World journal of surgery》2020,44(6):1824-1834
World Journal of Surgery - The goal of our study was to evaluate the differences in care and clinical outcomes of patients with chest trauma between two hospitals, including one public trauma... 相似文献