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排序方式: 共有3025条查询结果,搜索用时 15 毫秒
31.
Yara Barbosa Franco Clever Aparecido Valentin Marcelo Kobelnik Jefferson Lins da Silva Clovis Augusto Ribeiro Marta Pereira da Luz 《Materials》2022,15(12)
Nonwoven geotextiles are geosynthetic products that are highly susceptible to ultraviolet degradation because light can reach a large area of the material due to its fiber arrangement. Even with additives, which delay the degradation process, material decomposition still occurs, and therefore the product’s long-term durability can be affected. In this paper, the mechanical and thermal behavior of a commercial nonwoven polyester geotextile subjected to accelerated ultraviolet aging tests were evaluated. The deterioration was evaluated by comparing the physical properties (mass per unit area, thickness, and tensile strength) and thermal behavior (thermogravimetry—TG, thermomechanical analysis—TMA, and differential scanning calorimetry—DSC) before and after exposure times of 500 h and 1000 h. The results showed that the ultraviolet aging tests induced some damage in the polyester fibers, leading to the deterioration of their tensile strength. For 1000 h of exposure, in which the reduction was larger, scanning electron microscopy (SEM) found some superficial disruption of the fibers, indicative of damage. TG and DSC could not capture the effects of UV radiation on polymer degradation, unlike TMA. This latter technique was effective in showing the differences between specimens before and after UV exposure. 相似文献
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33.
Tôrres Luísa Helena do Nascimento Silva Débora Dias da Neri Anita Liberalesso Hilgert Juliana Balbinot Hugo Fernando Neves Sousa Maria da Luz Rosário de 《Nutrition (Burbank, Los Angeles County, Calif.)》2013,29(1):152-157
ObjectivePoor oral status, represented by partial/complete tooth loss, may lead to changes in food choice, which may ultimately lead to underweight, overweight, or obesity. The aim of this study is to evaluate whether poor oral status is associated with underweight or overweight/obesity, regardless of physical activity.MethodsThis cross-sectional study is part of a major project, The Frailty in Brazilian Elderly Study, carried out in Campinas, Brazil (2008–2009). The sample was composed of 900 independent-living older adults. Complete data were available for 875 individuals including sociodemographic, self-reported amount of medications used and eating difficulty questionnaire, smoking habit, depressive symptoms, physical activity, oral examination, and anthropometric assessments according to the WHO criteria. Body mass index was used as an outcome. Multinomial logistic regression was adjusted for confounding variables.ResultsThe mean age of the sample was 72.7 y (±5.81) and the prevalence of edentulism was 47.7%. Edentate individuals not wearing dentures were more likely to be underweight [odds ratio (OR) = 3.94, 95% confidence interval (CI) 1.14–13.64] and overweight/obese (OR = 2.88, 95%CI 1.12–7.40). Males (OR = 0.56, 95%CI 0.36–0.85) and those not using medications (OR = 0.41 95%CI 0.24–0.70) were less likely to be overweight/obese. Individuals who smoke (OR = 2.62, 95%CI 1.26–5.44) were more likely to be underweight. Older individuals with family income between 3.1 and 5 minimum wage (OR = 1.69, 95%CI 1.00–2.87) were more likely to be overweight/obese.ConclusionTo our knowledge, this is one of the first studies associating poor oral health, represented by edentulism not rehabilitated with dentures, with unfavorable body mass, regardless of the two major confounders, physical activity and depression symptoms. 相似文献
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35.
Luz Balsalobre Montserrat Ortega Adela G. de la Campa 《Antimicrobial agents and chemotherapy》2013,57(1):254-260
Fourteen fluoroquinolone-resistant streptococcal isolates with recombinant DNA topoisomerase genes, preliminarily identified as pneumococci, were further characterized using phenotypic and genotypic approaches. Phenotypic tests classified them as atypical pneumococci. Phylogenetic relationships were analyzed by using the sequences of seven housekeeping alleles from these isolates and from isolates of Streptococcus pneumoniae, Streptococcus mitis, Streptococcus oralis, and Streptococcus pseudopneumoniae. Four isolates grouped with S. pneumoniae, seven grouped with S. pseudopneumoniae, and three grouped with S. mitis. These results generally agreed with those obtained with an optochin susceptibility test and with the organization of the atp operon chromosomal region, encoding the FoF1 H+-ATPase (the target of optochin). All seven isolates grouping with S. pseudopneumoniae share the same spr1368-atpC-atpA gene order; all four grouping with S. pneumoniae share the spr1368-IS1239-atpC-atpA order, and two out of the three grouping with S. mitis share the spr1284-atpC-atpA order. In addition, evidence for recombination within the seven housekeeping alleles of the S. pseudopneumoniae population was provided by several methods: the index of association (0.4598, P < 0.001), the pairwise homoplasy index, and the split-decomposition method. This study confirms the existence of pneumococci among the alpha-hemolytic streptococci with DNA topoisomerase genes showing a mosaic structure and reveals a close relationship between atypical pneumococci and S. pseudopneumoniae. 相似文献
36.
Sergio Fernandez-Pello Luis Rodriguez Villamil Ivan Gonzalez Rodriguez Victoria Venta Javier Cuervo Carmen Luz Menéndez 《World Journal of Clinical Cases》2013,1(3):121-123
We report the case of a left laparoscopic nephroureterectomy with the incidental discovery of a non-Hodgkin’s lymphoma in one of the lymph nodes of the renal hilum. A laparoscopic nephroureterectomy was decided on for a 64-year-old man. Renal cell carcinoma in the kidney and one lymph node of the renal hilum with non-Hodgkin’s lymphoma was found. Chemotherapy was not started for the lymphoma discovery. There are no signs of relapse after two years of follow up. Coexistence in the same patient is an extremely rare condition. We review the literature about this issue to clarify this association. 相似文献
37.
Francisco J Gómez-Pérez Carlos A Aguilar-Salinas Cuauhtémoc Vázquez-Chávez Guillermo Fangh?nel-Salmón José Gallegos-Martínez Rita A Gómez-Diaz Saul Salinas-Orozco Ismael J Chavira-López Leticia Sánchez-Reyes Evelyn M Torres-Acosta Ricardo Tamez Angelina López Luz E Guillén Gabriela Cesarman 《Metabolism: clinical and experimental》2002,51(1):44-51
The effects of troglitazone 400 or 600 mg/d on the glycemic control, very-low-density lipoprotein (VLDL), and high-density lipoprotein (HDL) subclass concentrations and plasminogen-activator inhibitor 1 (PAI-1) levels were assessed in patients with type 2 diabetes that had not been controlled with dietary treatment. This was a multicenter, open-label, parallel-groups study. It included a run-in 4-week diet period and a 24-week randomized treatment. Fifty one patients received 400 mg/d and 55 patients 600 mg. The mean HbA(1c) concentration at the end of the study was similar for both doses. Troglitazone, regardless of dose, significantly improved insulin sensitivity assessed by the homeostasis model (HOMA). PAI-1 levels were significantly decreased in both groups by 13%. Higher HDL cholesterol concentrations and lower triglycerides levels were observed at the end of treatment. Triglyceride contents were reduced only in the lighter VLDL1. The change in HDL cholesterol concentration resulted from a combination of increased HDL3 cholesterol and lower HDL2 cholesterol levels. No differences were found in the effects of both treatment groups on the evaluated parameters. Our data provide new information about the actions of the drug on the lipid profile. Troglitazone reduces triglyceride levels by lowering the triglycerides content of the VLDL1 particles and increases HDL cholesterol concentrations by increasing HDL3 cholesterol levels. 相似文献
38.
Coutinho HM McGarvey ST Acosta LP Manalo DL Langdon GC Leenstra T Kanzaria HK Solomon J Wu H Olveda RM Kurtis JD Friedman JF 《The Journal of infectious diseases》2005,192(3):528-536
In a cross-sectional study of 641 Schistosoma japonicum-infected individuals in Leyte, Philippines, who were 7-30 years old, we determined the grade of hepatic fibrosis (HF) by ultrasound and used anthropometric measurements and hemoglobin levels to assess nutritional status. Serum levels of interleukin (IL)-1, IL-6, and IL-10; tumor-necrosis factor (TNF)-alpha; soluble TNF- alpha receptor I; and C-reactive protein (CRP) were measured to examine the association between these markers of inflammation and HF grade. HF was present in 8.9% of the cohort; the majority of cases were mild (grade I), and severe (grade II or grade III) cases occurred only in male individuals. Compared with individuals without HF, those with severe HF--and, to a lesser degree, those with mild HF--had a significantly lower body-mass index (BMI) and BMI z-score, a higher prevalence of anemia, and a higher level of CRP and were more likely to produce IL-6; furthermore, those with severe HF had a significantly higher level of IL-1, compared with those either without HF or with mild HF. These findings suggest that even mild HF is associated with nutritional morbidity and underscore the importance of early recognition and treatment. In addition, our data are consistent with the hypothesis that, by systemically increasing the levels of the proinflammatory cytokines IL-1 and IL-6, HF causes undernutrition and anemia. 相似文献
39.
Protásio L. da Luz L.F.Monteiro de Barros João Jorge Leite Fúlvio Pileggi Luiz V. Décourt 《The American journal of cardiology》1980,45(2):269-275
To elucidate the mechanism of action of the calcium antagonist verapamil, S-T segment mapping, retrograde coronary flow and regional coronary resistance were studied in 28 dogs subjected to acute coronary occlusion. Retrograde coronary flow was measured directly through catheterization of the distal occluded coronary artery. Regional coronary resistance was calculated by dividing mean distal coronary pressure by coronary flow. Verapamil (0.8 mg/kg) administered intravenously to eight dogs 30 minutes before coronary occlusion significantly reduced S-T segment elevation as compared with occlusion alone (p < 0.025); heart rate and diastolic pressure were also reduced (p < 0.05) but systolic pressure remained essentially unchanged. When verapamil was given to seven dogs within 30 minutes after coronary occlusion, there was a significant increase in retrograde coronary flow (p < 0.05) and a decrease in regional coronary resistance (p < 0.05). Simultaneously, heart rate and heart rate-blood pressure product declined significantly (p < 0.05), suggesting a reduction in myocardial oxygen consumption. Systolic blood pressure was unaltered, and diastolic pressure decreased only transiently. In 13 control dogs there was no significant change in any of these variables during the observation period. Thus, verapamil during acute coronary occlusion protects the ischemic myocardium by both increasing perfusion and reducing myocardial oxygen consumption. 相似文献
40.
Betzana Zambrano Fernando Noriega Gustavo H. Dayan Doris Maribel Rivera Jos Luis Arredondo Humberto Reynales Kleber Luz Carmen Deseda Matthew I. Bonaparte Edith Langevin Yukun Wu Margarita Corts Stephen Savarino Carlos A. DiazGranados 《The American journal of tropical medicine and hygiene》2021,104(1):136