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41.
In the auditory brain, some populations of neurons exhibit stimulus-specific adaptation (SSA), whereby they adapt to frequently occurring stimuli but retain sensitivity to stimuli that are rare. SA has been observed in auditory structures from the midbrain to the primary auditory cortex (A1) and has been proposed to be a precursor to the generation of deviance detection. SSA is strongly expressed in non-lemniscal regions of the medial geniculate body (MGB), the principal nucleus of the auditory thalamus. In this account we review the state of the art of SSA research in the MGB, highlighting the importance of this auditory centre in detecting sounds that may be relevant for survival. 相似文献
42.
J. Mourão J. Machado C. Novais P. Antunes L. Peixe 《European journal of clinical microbiology & infectious diseases》2014,33(12):2249-2257
To better understand the recent success/emergence of Salmonella enterica serotype 4,[5],12:i:- we characterized the population diversity, fljAB deletion patterns, antibiotic resistance features and associated genetic elements of a comprehensive collection obtained in the last decade from Portugal (2002–2010). One hundred thirty-one isolates from human clinical specimens, food, environment and piggeries, verified by PCR as S. 4,[5],12:i:-, were studied for clonality (Pulsed-Field Gel Electrophoresis and Multilocus Sequence Typing), antibiotic resistance by phenotypic (disk diffusion and/or agar dilution) and genotypic (PCR/Restriction Fragment Length Polymorphism and sequencing, genomic location) methods and fljAB-deletions (PCR). Plasmid analysis included determination of size, content and characterization of the incompatibility group (PCR-Based Replicon Typing and I-CeuI/S1-hybridization). Results showed three multidrug-resistant (MDR) clones circulating and causing infections, associated with particular phenotypic and genotypic features. Most of the isolates belonged to the widespread European (ASSuT phenotype, RR1-RR2 resistance regions, ST34) and Spanish (carrying a sul3-type III integron within IncA/C plasmids, ST19) clones circulating in Europe. A third clone, here designated Southern European clone (carrying a sul3-type I integron within IncR plasmids, ST19), presents a fljAB region different from the previous clones and similar to the US strains, despite differences in the MDR mobile genetic platforms. The success of S. 4,[5],12:i:- might be related to the selective advantage offered by MDR profiles associated with stable genetic elements, also carrying virulence features, along with well adapted clones to the animal food production and causing human infections. 相似文献
43.
José Pedro Pinto Agostinho Cordeiro Ana Margarida Ferreira Concei??o Antunes Patrícia Botelho Ana Jo?o Rodrigues Pedro Le?o 《World journal of gastroenterology : WJG》2014,20(36):13191-13194
Ileal intussusception is the invagination of the small intestine within itself and accounts for 1% of cases of acute obstruction. However, physicians do not initially consider intussusception as a possible diagnosis of obstruction due to its rarity in adults. Herein, we report the case of a 22-year-old male who was admitted to the Emergency Department with continuous abdominal pain. Ultrasonography and computed tomography revealed an ileal intussusception. The patient underwent surgical removal of the segment of the small bowel. Unexpectedly, pathology revealed that the invagination occurred due to a parasite egg, with features suggestive of Schistosoma species. Schistosomiasis, although considered a parasitic disease in tropical countries, is not absent from Europe and though it is highly improbable, it may be responsible for cases of intussusception in adults. 相似文献
44.
Pizzaia Daniel Nogueira Marina Lima Mondin Mateus Carvalho Marcia Eugenia Amaral Piotto Fernando Angelo Rosario Millor Fernandes Azevedo Ricardo Antunes 《Ecotoxicology (London, England)》2019,28(9):1046-1055
Ecotoxicology - This study aimed to investigate the mode of action of cadmium (Cd) toxicity at cell level, especially at early stages of plant exposure. Tomato seedlings were cultivated in growth... 相似文献
45.
Maria Auxiliadora Nogueira Saad Gilberto Perez Cardoso Wolney de Andrade Martins Luis Guillermo Coca Velarde Rubens Antunes da Cruz Filho 《Arquivos brasileiros de cardiologia》2014,102(3):263-269
Background
Metabolic syndrome (MS) is an aggregation of risk factors that increase the incidence of cardiovascular events and diabetes mellitus (DM). Population aging is accompanied by higher prevalence of MS, which varies depending on the population studied and the diagnostic criteria used.Objective
To determine prevalence of MS in the elderly using four diagnostic criteria and agreement between them.Methods
Cross-sectional study on 243 patients older than 60 years (180 women) in Niterói, RJ. They were evaluated by clinical examination, fasting glucose, fasting insulin, lipid profile and anthropometric measurements - weight, height, waist circumference and waist/hip ratio. Prevalence of MS was estimated by World Health Organization (WHO) modified, National Cholesterol Education Program - Adult Treatment Panel III (NCEP-ATP III), International Diabetes Federation (IDF) and Joint Interim Statement (JIS) criteria.Results
Prevalence was high with the four criteria WHO (51.9%), NCEP-ATPIII (45.2%), IDF (64.1%) and JIS (69.1%), and agreement between criteria by kappa was moderate in almost all comparisons WHO vs. IDF (k = 0.47;95% confidence interval (CI), 0.35 to 0.58); WHO vs. NCEP-ATPIII (k = 0.51; 95% CI, 0.40 to 0.61); WHO vs. JIS (k = 0.45; 95% CI, 0.33 to 0.56); IDF vs. NCEP-ATPIII (k = 0.55; 95% CI, 0.45 to 0.65) and NCEP-ATPIII vs. JIS (k = 0.53; 95% CI, 0.43-0.64), except between IDF vs. JIS (K = 0.89;95% CI, 0.83 to 0.95), which was considered good.Conclusion
Prevalence of MS was high with the four diagnostic criteria, mainly by JIS. There was good agreement between JIS and IDF criteria and moderate among the others. 相似文献46.
Santos Tde S Antunes AA Vajgel A Cavalcanti TB Nogueira LR Laureano Filho JR 《The Journal of craniofacial surgery》2012,23(2):e119-e123
Two cases of swallowing of foreign material related to dental implants during dental practice are described. A conservative approach by clinical-radiographic follow-up was performed in both cases; however, one of the patients required colonoscopy under general anesthesia for the removal of the impacted foreign body from the intestinal region. These complications not only have associated economic cost but also carry the risk of malpractice litigation against the professional; thus, the surgeon was responsible for all the costs of hospital and surgery management of this case. Details of the clinical signs, radiographic examinations, type of treatment, and follow-up are presented. 相似文献
47.
Borges KS Castro-Gamero AM Moreno DA da Silva Silveira V Brassesco MS de Paula Queiroz RG de Oliveira HF Carlotti CG Scrideli CA Tone LG 《Journal of cancer research and clinical oncology》2012,138(3):405-414
Background
Glioblastoma remains one of the most devastating human malignancies, and despite therapeutic advances, there are no drugs that significantly improve the patient survival. Altered expression of the Aurora kinases was found in different malignancies, and their inhibition has been studied in cancer therapy. In this study, we analyzed the expression of Aurora A and Aurora B in glioblastoma samples and also analyzed whether the effects of Aurora kinase inhibition were associated with temozolomide or not on cell lines and primary cultures of glioblastoma. 相似文献48.
49.
Ovandir Bazan Jayme Pinto Ortiz Francisco Ubaldo Vieira Junior Reinaldo Wilson Vieira Nilson Antunes Fabio Bittencourt Dutra Tabacow Eduardo Tavares Costa Orlando Petrucci Junior 《Brazilian Journal Of Cardiovascular Surgery》2013,28(4):462-469
Introduction
In vitro hydrodynamic characterization of prosthetic heart valves provides important information regarding their operation, especially if performed by noninvasive techniques of anemometry. Once velocity profiles for each valve are provided, it is possible to compare them in terms of hydrodynamic performance. In this first experimental study using laser doppler anemometry with mechanical valves, the simulations were performed at a steady flow workbench.Objective
To compare unidimensional velocity profiles at the central plane of two bi-leaflet aortic prosthesis from St. Jude (AGN 21 - 751 and 21 AJ - 501 models) exposed to a steady flow regime, on four distinct sections, three downstream and one upstream.Methods
To provide similar conditions for the flow through each prosthesis by a steady flow workbench (water, flow rate of 17L/min. ) and, for the same sections and sweeps, to obtain the velocity profiles of each heart valve by unidimensional measurements.Results
It was found that higher velocities correspond to the prosthesis with smaller inner diameter and instabilities of flow are larger as the section of interest is closer to the valve. Regions of recirculation, stagnation of flow, low pressure, and flow peak velocities were also found.Conclusions
Considering the hydrodynamic aspect and for every section measured, it could be concluded that the prosthesis model AGN 21 - 751 (RegentTM) is superior to the 21 AJ - 501 model (Master Series). Based on the results, future studies can choose to focus on specific regions of the these valves. 相似文献50.
Fernandes MA Batista GI Carlos Jda C Gomes IM Azevedo KM Setúbal S Oliveira SA Velarde LG Cardoso CA 《The Brazilian journal of infectious diseases》2012,16(2):170-1174
ObjectiveCompare the anti-T. gondii IgG titer between HIV-1 infected and non HIV-1 infected pregnant women and report three cases of congenital toxoplasmosis resulting from reactivation of infection during pregnancy of HIV-1 infected women.MethodsThis study was conducted among 2,270 pregnant women with chronic Toxoplasma gondii infection (absence of IgM and presence of IgG), including 82 HIV-1 infected and 2,188 non-infected women.ResultsThe average anti-T. gondii IgG titer was 127 for the 2,188 non-HIV-1 infected women, and 227 for the 82 HIV-1-infected women (p = 0,007). These results suggested that higher anti-T. gondii IgG titers in HIV-1-infected pregnant women may not be indicative of an elevated risk for fetal infection. In this study three cases of congenital toxoplasmosis that resulted from infection reactivation during pregnancy of HIV-1-infected women were manifested by fetal death, symptomatic infection, and infant without symptoms, respectively. In two of these women, a ten-fold increase in IgG levels above used cutoff was observed (2,320 UI/mL and 3,613 UI/mL, respectively). In the third pregnant women anti-T. gondii IgG titers during pregnancy did not rise despite the occurrence of congenital toxoplasmosis (204; 198; 172 UI/mL).ConclusionsCongenital toxoplasmosis resulting reactivation of infection during pregnancy in the studied group leads us to believe that it is a public health problem, especially in our population, in which seroprevalence of T. gondii infections is high. These findings also suggest that special attention is necessary during pregnancy, because the serologic diagnosis may not be indicative of toxoplasmosis reactivation. 相似文献