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991.
da Silva Mauro Roberto Biá Brandão Natália Alberto Alves Colovati Marco de Sousa Margella Marconcine Pinheiro de Lima Larissa Coelho Dorta Miriam Leandro Ribeiro-Dias Fátima Costa Dorcas Lamounier Costa Carlos Henrique Nery de Oliveira Milton Adriano Pelli 《Parasitology research》2018,117(2):419-427
Parasitology Research - Because of visceral leishmaniasis (VL) urbanization and spreading of the human immunodeficiency virus (HIV) infection to rural areas, coinfection has become more common.... 相似文献
992.
993.
Dallan PR Moreira Pda L Petinari L Malmonge SM Beppu MM Genari SC Moraes AM 《Journal of biomedical materials research. Part B, Applied biomaterials》2007,80(2):394-405
The aim of this work was to perform a systematic study about the effects induced by chitosan solution concentration and by chitin or glycerol incorporation on dense chitosan membranes with potential use as burn dressings. The membrane properties analyzed were total raw material cost, thickness, morphology, swelling ratio, tensile strength, percentage of strain at break, crystallinity, in vitro enzymatic degradation with lysozyme, and in vitro Vero cells adhesion. While the use of the most concentrated chitosan solution (2.5% w/w) increased membrane cost, it also improved the biomaterial mechanical resistance and ductility, as well as reduced membrane degradation when exposed for 2 months to lysozyme. The remaining evaluated properties were not affected by initial chitosan solution concentration. Chitin incorporation, on the other hand, reduced the membranes cost, swelling ratio, mechanical properties, and crystallinity, resulting in thicker biomaterials with irregular surface more easily degradable when exposed to lysozyme. Glycerol incorporation also reduced the membranes cost and crystallinity and increased membranes degradability after exposure to lysozyme. Strong Vero cells adhesion was not observed in any of the tested membrane formulations. The overall results indicate that the majority of the prepared membranes meet the performance requirements of temporary nonbiodegradable burn dressings (e.g. adequate values of mechanical resistance and ductility, low values of in vitro cellular adhesion on their surfaces, low extent of degradation when exposed to lysozyme solution, and high stability in aqueous solutions). 相似文献
994.
Leandro Machín Jessica Aschemann-Witzel María Rosa Curutchet Ana Giménez Gastón Ares 《Journal of nutrition education and behavior》2018,50(7):668-674
Objective
To evaluate how information about low nutrient content included in the traffic light labeling system influences consumers' perception of the healthfulness of products with high content of 1 key nutrient, and to compare the traffic light system with warnings in terms of the perception of healthfulness.Design
Images of front-of-pack (FOP) nutrition labels (the traffic light labeling system with different numbers of nutrients with low content, and warnings) were evaluated in study 1, whereas product labels featuring the different FOP nutrition labels were evaluated in study 2.Setting
Online studies conducted in Montevideo, Uruguay.Participants
A total of 1,228 Uruguayan Facebook users.Main Outcome Measures
Perception of healthfulness.Analysis
The researchers used ANOVA to evaluate the influence of FOP nutrition labels on perceived healthfulness.Results
The inclusion of information about low nutrient content in the traffic light system statistically significantly increased the perception of the healthfulness of products with high nutrient content. Nutritional warnings showed healthfulness ratings similar to those of the simplified version of the traffic light system.Conclusions and Implications
Information about low nutrient content in the traffic light system might be used to infer health, and thus could raise the perception of healthfulness and decrease the traffic light system's efficacy in discouraging the consumption of unhealthful products. A simplified version of the traffic light highlighting only high-nutrient content or nutritional warnings seems to overcome this problem. 相似文献995.
996.
Leonardo Shigaki Edgar Ramos Vieira André Wilson de Oliveira Gil Cynthia Gobbi Alves Araújo Mariana Zingari Carmargo Leandro Amaral Sturion Marcio Roǵerio de Oliveira Rubens A. da Silva 《Journal of manipulative and physiological therapeutics》2017,40(4):284-292
Objective
The purpose of this study was to assess the effect of holding an external load on the standing balance of younger and older adults with and without chronic low back pain (CLBP).Methods
Twenty participants with and 20 without CLBP participated in the study. Each group contained 10 younger (50% men) and 10 older adults (50% men). Participants were instructed to look straight ahead while standing on a force platform during two 120-second trials with and without holding an external load (10% of body mass). The center of pressure area, mean velocity, and mean frequency in the anteroposterior and mediolateral directions were measured.Results
Older adults had worse standing balance than younger adults did (P < .001, d = 0.20). There were no significant balance differences between participants with and without CLBP within age groups during standing balance condition. However, holding the external load significantly increased postural instability for both age groups and CLBP status, with mean effect size across center of pressure variables of d = 0.82 for older participants without CLBP and d = 2.65 for younger participants without CLBP. These effects for people with CLBP were d = 1.65 for subgroup of older and d = 1.60 for subgroup of younger participants.Conclusion
Holding an external load of 10% of body mass increased postural instability of both younger and older adults with and without CLBP. 相似文献997.
Clinical concentrations of thioridazine kill intracellular multidrug-resistant Mycobacterium tuberculosis 下载免费PDF全文
Ordway D Viveiros M Leandro C Bettencourt R Almeida J Martins M Kristiansen JE Molnar J Amaral L 《Antimicrobial agents and chemotherapy》2003,47(3):917-922
The phenothiazines chlorpromazine (CPZ) and thioridazine (TZ) have equal in vitro activities against antibiotic-sensitive and -resistant Mycobacterium tuberculosis. These compounds have not been used as anti-M. tuberculosis agents because their in vitro activities take place at concentrations which are beyond those that are clinically achievable. In addition, chronic administration of CPZ produces frequent severe side effects. Because CPZ has been shown to enhance the killing of intracellular M. tuberculosis at concentrations in the medium that are clinically relevant, we have investigated whether TZ, a phenothiazine whose negative side effects are less frequent and serious than those associated with CPZ, kills M. tuberculosis organisms that have been phagocytosed by human macrophages, which have nominal killing activities against these bacteria. Both CPZ and TZ killed intracellular antibiotic-sensitive and -resistant M. tuberculosis organisms when they were used at concentrations in the medium well below those present in the plasma of patients treated with these agents. These concentrations in vitro were not toxic to the macrophage, nor did they affect in vitro cellular immune processes. TZ thus appears to be a serious candidate for the management of a freshly diagnosed infection of pulmonary tuberculosis or as an adjunct to conventional antituberculosis therapy if the patient originates from an area known to have a high prevalence of multidrug-resistant M. tuberculosis isolates. Nevertheless, we must await the outcomes of clinical trials to determine whether TZ itself may be safely and effectively used as an antituberculosis agent. 相似文献
998.
Giuseppe Pastore Francesco Paolo Schena Gioacchino Angarano Laura Monno Teresa Santantonio Giovanni Pertosa 《International Journal of Clinical & Laboratory Research》1984,14(1):29-35
Summary Circulating immune complexes (CIC) were investigated by the fluid-phase Clq binding test in serum samples from 131 subjects
with various clinical types of HBsAg-positive and HBsAg-negative chronic hepatitis diagnosed on both clinical and laboratory
criteria, including liver biopsy; serum samples from 28 asymptomatic HBsAg carriers and 75 healthy controls were also examined.
The results of these findings were correlated with the liver damage and the clinical course of the disease. CIC were detected
in all categories of chronic hepatitis with a significant prevalence only in patients with liver cirrhosis. No correlation
was found between the leveis of CIC, the presence of circulating HBsAg, and active inflammation or necrosis in any of the
different types of chronic hepatitis. In contrast, a highly significant correlation was found between the prevalence of CIC
and a more severe prognosis in patients with CAH and liver cirrhosis. The findings suggest that the presence of CIC is not
specific for a given type of chronic liver disease and that they do not play any role in the pathogenesis of liver damage.
The correlation observed between the presence of CIC and an unfavourable course of chronic liver disease suggests that CIC
may modify the host’s immune defence mechanisms.
This work was supported in part by grants from theConsiglio Nazionale delle Ricerche (CNR) and from theMinistero della Pubblica Istruzione, Roma, Italy. 相似文献
999.
1000.
Alcoholism (alcohol dependence) is characterized by a compulsion to seek and ingest alcohol (ethanol), loss of control over intake, and the emergence of a negative emotional state during withdrawal. Animal models are critical in promoting our knowledge of the neurobiological mechanisms underlying alcohol dependence. Here, we review the studies involving operant alcohol self-administration in rat models of alcohol dependence and withdrawal with the focus on the alcohol vapor model. In 1996, the first articles were published reporting that rats made dependent on alcohol by exposure to alcohol vapors displayed increased operant alcohol self-administration during acute withdrawal compared with nondependent rats (i.e., not exposed to alcohol vapors). Since then, it has been repeatedly demonstrated that this model reliably produces physical and motivational symptoms of alcohol dependence. The functional roles of various systems implicated in stress and reward, including opioids, dopamine, corticotropin-releasing factor (CRF), glucocorticoids, neuropeptide Y (NPY), γ-aminobutyric acid (GABA), norepinephrine, and cannabinoids, have been investigated in the context of alcohol dependence. The combination of models of alcohol withdrawal and dependence with operant self-administration constitutes an excellent tool to investigate the neurobiology of alcoholism. In fact, this work has helped lay the groundwork for several ongoing clinical trials for alcohol dependence. Advantages and limitations of this model are discussed, with an emphasis on what future directions of great importance could be. 相似文献