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排序方式: 共有3771条查询结果,搜索用时 31 毫秒
81.
Sara Proietti Alessandra Cucina Gabriella Dobrowolny Fabrizio D'Anselmi Simona Dinicola Maria Grazia Masiello Alessia Pasqualato Alessandro Palombo Veronica Morini Russel J. Reiter Mariano Bizzarri 《Journal of pineal research》2014,57(1):120-129
Compelling evidence demonstrated that melatonin increases p53 activity in cancer cells. p53 undergoes acetylation to be stabilized and activated for driving cells destined for apoptosis/growth inhibition. Over‐expression of p300 induces p53 acetylation, leading to cell growth arrest by increasing p21 expression. In turn, p53 activation is mainly regulated in the nucleus by MDM2. MDM2 also acts as E3 ubiquitin ligase, promoting the proteasome‐dependent p53 degradation. MDM2 entry into the nucleus is finely tuned by two different modulations: the ribosomal protein L11, acts by sequestering MDM2 in the cytosol, whereas the PI3K‐AkT‐dependent MDM2 phosphorylation is mandatory for MDM2 translocation across the nuclear membrane. In addition, MDM2‐dependent targeting of p53 is regulated in a nonlinear fashion by MDM2/MDMX interplay. Melatonin induces both cell growth inhibition and apoptosis in MCF7 breast cancer cells. We previously reported that this effect is associated with reduced MDM2 levels and increased p53 activity. Herein, we demonstrated that melatonin drastically down‐regulates MDM2 gene expression and inhibits MDM2 shuttling into the nucleus, given that melatonin increases L11 and inhibits Akt‐PI3K‐dependent MDM2 phosphorylation. Melatonin induces a 3‐fold increase in both MDMX and p300 levels, decreasing simultaneously Sirt1, a specific inhibitor of p300 activity. Consequently, melatonin‐treated cells display significantly higher values of both p53 and acetylated p53. Thus, a 15‐fold increase in p21 levels was observed in melatonin‐treated cancer cells. Our results provide evidence that melatonin enhances p53 acetylation by modulating the MDM2/MDMX/p300 pathway, disclosing new insights for understanding its anticancer effect. 相似文献
82.
José Saura Llamas María Nieves Martínez Garre María Elena Sebastián Delgado María Ángeles Martínez Navarro Mariano Leal Hernández Susana Blanco Sabio Antonio Martínez Pastor 《Atencion primaria / Sociedad Espa?ola de Medicina de Familia y Comunitaria》2013,45(6):297-306
ObjectiveTo evaluate the performance and quality of the 10 groups of training tasks envisaged in the portfolio training model undertaken by all residents of the Primary Care Teaching Unit in Murcia.DesignA cross-sectional study was conducted on the portfolios provided and completed by all residents in May 2011.ParticipantsAll residents who were in training at that time (131).MethodTen groups of training tasks were established from those recommended by the National Commission for the specialty. The performance of each one in each of the portfolios was evaluated, and the compliance for each training task was calculated. The quality of the performance of each of the tasks was given a score, 0 points (very poor) to 10 points (excellent).ResultsAs regards compliance, the tasks that were most performed were: filling in the Resident book correctly and using the resident skills guide, both with 99.24%, followed by reflection reports on the training visits. All tasks had a compliance rate higher than 67%. The mean percentage of compliance was 86.49%. All tasks obtained an average score greater than 7 (outstanding). The overall mean score was 7,8 points.ConclusionsThe level of perfomance of the tasks set out in the portfolio by the residents was very satisfying. It is necessary to continue working on improving the performance of the portfolio. 相似文献
83.
Isabel Pascual Gemma Fernández de Miguel Mariano García Arranz Damián García-Olmo 《International journal of colorectal disease》2010,25(12):1447-1451
Purpose
Use of biosutures in animal models of colonic anastomoses is associated with decreased adhesions without affecting anastomotic strength. This study aimed to evaluate the effect of biosutures on colonic anastomoses kept free of adhesions by peritoneal instillation of icodextrin 4%. 相似文献84.
85.
86.
Romina C. De Lucca Patricio L. Dutrey Mariano E. Villarino Angela M. Ubios 《Experimental and toxicologic pathology》2009,61(4):347-352
Not only workers employed at industrial plants are exposed to intoxication with the element they manipulate, the population at large is also at risk of suffering health problems caused by contaminating wastes inadequately treated for their safe disposal. As a result certain toxic substances, such as hexavalent chromium,has reached the general population including children. The present study sought to evaluate the effect of intoxication with hexavalent chromium on body and mandibular growth and tooth eruption in suckling Wistar rats. Potassium dichromate was administered by gavage in a dose of 6.25 or 12.5 mg/kg body weight (b.w.) to one of the two groups of 4-day-old Wistar rats during 10 days. Our results showed that the effects of chromium are dose-dependent. Morphometric studies of body growth showed lower body weight in both experimental groups and shorter tail length in animals receiving 12.5 mg/kg b.w. dose of chromium, compared with controls. All parameters of mandibular growth were lower in the experimental group receiving 12.5 mg/kg b.w. of chromium. Differences in tooth eruption were observed at the level of the first molar in animals receiving 12.5 mg/kg and of the second molar in those receiving 6.25 mg/kg b.w. of chromium. Chromium was found to affect all the studied parameters. 相似文献
87.
Saura D Campos JV Villegas M Picó F de la Morena G Valdés-Chávarri M 《International journal of cardiology》2008,129(1):e7-e9
Heart–hand syndromes show substantial clinical and genetic heterogeneity. The unusual case of a patient with a heart–hand syndrome consisting of preaxial polydactylia, postaxial syndactylia, parachute mitral valve, mild subaortic stenosis, and double outlet right ventricle is presented and discussed. The importance of distinguishing Holt–Oram syndrome from its phenocopies and other heart–hand syndromes is underlined. 相似文献
88.
89.
Unsafe Drug Use and Arrhythmic Events in Brugada Patients with ICD: Results of a Long-Term Follow-Up
Diogo de Almeida Fernandes Natália António Marta Madeira Pedro Sousa Miguel Ventura João Cristóvão José Nascimento Luís Elvas Lino Gonçalves Guilherme Mariano Pego 《Cardiovascular drugs and therapy / sponsored by the International Society of Cardiovascular Pharmacotherapy》2018,32(1):23-28