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31.
The relationship between platelet density and platelet age appears to vary between species with relatively few labeling studies in humans reported. In this study, irreversible monoamine oxidase (MAO) inhibitors were used to biochemically label the circulating platelet population in 15 humans. Platelet samples were then isolated during the 15 days after drug ingestion. The platelets were separated by density on continuous linear Percoll gradients and the density distributions were divided into five fractions containing approximately equal numbers of platelets. Baseline MAO activity was strongly correlated with platelet density. Twenty-four hours after a single dose of tranylcypromine, platelet MAO activities in the density subpopulations were reduced to 14% to 17% of the baseline values. During the first five days after inhibition, the rates of recovery of MAO activity (percentage per day) were inversely proportional to platelet density. The recovery rates in the two most dense fractions were initially slow but increased after five days. Percentage recovery of MAO activity in the least dense fraction was significantly greater than the percentage recovery in the most dense fraction on days 2, 3, 5, and 8 (P less than .01, sign test). These results support the hypothesis that normal human platelets show a small increase in density with age, but they do not exclude the additional possibility that human platelet lifespan is positively correlated with platelet density. 相似文献
32.
Aumento de Óbitos Domiciliares devido a Parada Cardiorrespiratória em Tempos de Pandemia de COVID-19
Nathalia Sernizon Guimares Taciana Malheiros Lima Carvalho Jackson Machado-Pinto Roger Lage Renata Mascarenhas Bernardes Alex Sander Sena Peres Mariana Amaral Raposo Ricardo Machado Carvalhais Renan Avelino Mancini Gabriella Yuka Shiomatsu Bruna Carvalho Oliveira Valria de Melo Rodrigues Maria do Carmo Barros de Melo Unaí Tupinambs 《Arquivos brasileiros de cardiologia》2021,116(2):266
BackgroundCardiovascular diseases constitute an important group of causes of death in the country. Ischemic heart diseases that are the main causes of cardiopulmonary arrest, leading to an impact on the mortality of the cardiovascular diseases in the health system.ObjectiveAssess the number of home deaths by cardiopulmonary arrest notified by the Mobile Emergency Medical Service (SAMU) in March 2018, 2019 and 2020.MethodsObservational study carried out from the analysis of cardiopulmonary arrest mortality data of citizens assisted by SAMU in Belo Horizonte, Minas Gerais, Brazil. Social and clinical characteristics and occurrence information of the patients were analyzed. The mortality rate due to cardiopulmonary arrest in relation to the total number of attendances was assessed. A significance level of 95% was considered.ResultsThere was increase of home deaths due to cardiopulmonary arrest in March 2020 compared to March 2018 (p<0.001) and March 2019 (p=0.050). Of the deaths reported in 2020, 63.8% of the patients were aged 60 years or older, 63.7% of the occurrences were performed in the afternoon and approximately 87% of the cardiopulmonary arrest notified had associated clinical comorbidities, with systemic arterial hypertension and heart failure represented by 22.87% and 13.03% of the reported cases, respectively. The majority of the evaluated sample of this study did not have any medical care follow-up (88.7%).ConclusionConsidering the increase in the number of the deaths, we suggest reflections and readjustments regarding the monitoring of chronic non-transmissible diseases during a pandemic, as well as improvements in death surveillance. (Arq Bras Cardiol. 2021; 116(2):266-271) 相似文献
33.
Maciel-de-Freitas R Peres RC Souza-Santos R Lourenço-de-Oliveira R 《Tropical medicine & international health : TM & IH》2008,13(12):1488-1494
Objectives To evaluate: (1) the occurrence, maintenance, productivity, spatial distribution and premise condition index score of Adese aegypti‐infested houses and key‐premises in a suburban district (Tubiacanga) and a slum (Favela do Amorim) of Rio de Janeiro and (2) the role of these factors in adult Ae. aegypti female spatial distribution. Methods and Results A total of 2456 premises were inspected for immature and 1100 for adult collection. Key‐premises corresponded to 16.08% and 17.86% of infested houses in Tubiacanga, and 13.5% and 11.1% in Favela do Amorim, during the dry and wet seasons, respectively. Key‐premises held significantly more immature Ae. aegypti, pupae and larvae than infested houses in Favela do Amorim and Tubiacanga during the dry and wet seasons. In Favela do Amorim, key‐premises had a significantly higher PCI score than infested but non‐key houses. Conclusion The spatial distribution of key‐premises and adult Ae. aegypti females was often congruent, indicating that key‐premises influence the infestation pattern observed in the study areas. 相似文献
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35.
Marcia F. da Silva Alexandre Y. Saito Valnice J. Peres Antonio C. Oliveira Alejandro M. Katzin 《Antimicrobial agents and chemotherapy》2015,59(8):5084-5087
Previous studies have shown that fosmidomycin, risedronate, and nerolidol exert antimalarial activity in vitro. We included squalestatin, an inhibitor of the isoprenoid metabolism in Erwinia uredovora, and found that combinations of compounds which act on different targets of the plasmodial isoprenoid pathway possess important supra-additivity effects. 相似文献
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38.
Madelon Novato Ribeiro Maria Inês Fernandes Pimentel Armando de Oliveira Schubach Raquel de Vasconcellos Carvalh?es de Oliveira José Liporage Teixeira Madson Pedro da Silva Leite Monique Fonseca Ginelza Peres Lima dos Santos Mariza Matos Salgueiro Erica de Camargo Ferreira e Vasconcellos Marcelo Rosandiski Lyra Mauricio Naoto Saheki Claudia Maria Valete-Rosalino 《Revista do Instituto de Medicina Tropical de S?o Paulo》2014,56(4):291-296
The favorable outcome of the treatment of a disease is influenced by the
adherence to therapy. Our objective was to assess factors associated with adherence
to treatment of patients included in a clinical trial of equivalence between the
standard and alternative treatment schemes with meglumine antimoniate (MA) in the
treatment of cutaneous leishmaniasis (CL), in the state of Rio de Janeiro. Between
2008 and 2011, 57 patients with CL were interviewed using a questionnaire to collect
socioeconomic data. The following methods were used for adherence monitoring:
counting of vial surplus, monitoring card, Morisky test and modified Morisky test
(without the question regarding the schedule); we observed 82.1% (vial return), 86.0%
(monitoring card), 66.7% (Morisky test) and 86.0% (modified Morisky test) adherence.
There was a strong correlation between the method of vial counting and the monitoring
card and modified Morisky test. A significant association was observed between
greater adherence to treatment and low dose of MA, as well as with a lower number of
people sleeping in the same room. We recommend the use of the modified Morisky test
to assess adherence to treatment of CL with MA, because it is a simple method and
with a good performance, when compared to other methods. 相似文献
39.
Zambon CE Ceccheti MM Utumi ER Pinna FR Machado GG Peres MP Voegels RL 《International journal of oral and maxillofacial surgery》2012,41(9):1120-1126
The present study sought to assess nasal respiratory function in adult patients with maxillary constriction who underwent surgically assisted rapid maxillary expansion (SARME) and to determine correlations between orthodontic measurements and changes in nasal area, volume, resistance, and airflow. Twenty-seven patients were assessed by acoustic rhinometry, rhinomanometry, orthodontic measurements, and use of a visual analogue scale at three time points: before surgery; after activation of a preoperatively applied palatal expander; and 4 months post-SARME. Results showed a statistically significant increase (p<0.001) in all orthodontic measurements. The overall area of the nasal cavity increased after surgery (p<0.036). The mean volume increased between assessments, but not significantly. Expiratory and inspiratory flow increased over time (p<0.001). Airway resistance decreased between assessments (p<0.004). Subjective analysis of the feeling of breathing exclusively through the nose increased significantly from one point in time to the next (p<0.05). There was a statistical correlation between increased arch perimeter and decreased airway resistance. Respiratory flow was the only variable to behave differently between sides. The authors conclude that the SARME procedure produces major changes in the oral and nasal cavity; when combined, these changes improve patients' quality of breathing. 相似文献
40.
Henn S de Carvalho RV Ogliari FA de Souza AP Line SR da Silva AF Demarco FF Etges A Piva E 《Clinical oral investigations》2012,16(2):531-536
This study evaluated the effect of zinc methacrylate (ZM) on the inhibition of matrix metalloproteinase 2 (MMP-2) and the
ultimate tensile strength (UTS) of an experimental polymer. Enzymes secreted from mouse gingival tissues were analyzed by
gelatin zymography in buffers containing 5 mM CaCl2 (Tris–CaCl2) in 50 mM Tris–HCl buffer with various concentrations of ZM (0.5, 1, 2, 4, 8, and 16 mM). The matrix metalloproteinases present
in the conditioned media were characterized by immunoprecipitation. The polymer UTS evaluation was performed in eight groups
with various concentrations of ZM (0, 0.5, 1, 2.5, 5, 10, 20, and 30 wt.%), in a mechanical testing machine. MMP-2 (62 kDa)
was detected in the zymographic assays and inhibited by ZM in all tested concentrations. UTS data were submitted to one-way
ANOVA and Tukey's test (α = 0.05), and no significant differences were observed among groups, except in the polymer containing 30% ZM, presenting a
significantly lower value when compared with the control group (p < 0.05). The results suggest that ZM inhibits MMP-2 expression in all concentrations tested, while small concentrations did
not affect the ultimate tensile strength of the polymer. Zinc methacrylate is a metalloproteinase inhibitor that can be copolymerized
with other methacrylate monomers. Yet, the addition of ZM did not affect the resin bond strength. Thus, in vivo tests should
be performed to evaluate the performance of this material. 相似文献