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Pesquisa : D01.268.406 [Categoria DeCS]
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Id: biblio-838341
Autor: Zapata-Castilleja, Carlos A; Montes-Tapia, Fernando F; Treviño-Garza, Consuelo; Martínez-Cobos, María C; García-Cantú, Jesús; Arenas-Fabbri, Vincenzo; de la O-Escamilla, Norma; de la O-Cavazos, Manuel.
Título: Comparación del incremento del perímetro abdominal con la prueba de hidrógeno espirado como predictor clínico de intolerancia a la lactosa / Comparison of an increased waist circumference with a positive hydrogen breath test as a clinical predictor of lactose intolerance
Fonte: Arch. argent. pediatr;115(2):148-154, abr. 2017. graf, tab.
Idioma: en; es.
Resumo: Introducción. La intolerancia a la lactosa es una afección frecuente en pediatría, cuyo diagnóstico erróneo conlleva morbilidad. El objetivo primario del estudio fue evaluar la utilidad del incremento del perímetro abdominal durante la prueba de hidrógeno espirado como predictor de intolerancia a la lactosa. El objetivo secundario fue analizar la influencia del índice de masa corporal, de la medida de la cintura y de la edad en la distensión abdominal de pacientes intolerantes a la lactosa. Población y métodos. Se incluyó a 138 sujetos de entre 3 y 15 años de edad a los cuales se les realizaron mediciones seriadas del perímetro abdominal y determinaciones de hidrógeno espirado cada 30 minutos por 3 horas, durante la prueba de hidrógeno espirado. Resultados. Del total de la muestra, 35 (25,4%) resultaron intolerantes a la lactosa. El incremento de 0,85 cm en el perímetro abdominal comparado con el perímetro abdominal basal tiene sensibilidad del 88% y especificidad del 85% para predecir intolerancia a la lactosa (OR 42,14; IC 95%: 13,08-135,75; p <0,001). El índice de masa corporal y la medida de la cintura no afectaron la distensibilidad del abdomen (p= NS); sin embargo, la edad modificó el momento de la distensión. Conclusiones. El incremento del perímetro abdominal de 0,85 cm en relación con el perímetro abdominal basal durante la prueba de hidrógeno espirado es un parámetro útil para diagnosticar la intolerancia a la lactosa en pediatría. Las variaciones en relación con el índice de masa corporal y la cintura no modificaron la utilidad del incremento del perímetro abdominal a diferencia de la edad.

Introduction. Lactose intolerance is a common disease in pediatrics, and its wrong diagnosis will lead to morbidity. The primary objective of this study was to assess the usefulness of an increased waist circumference during the hydrogen breath test as a predictor of lactose intolerance. The secondary objective was to analyze the impact of body mass index, waist circumference measurement, and age on the abdominal distension of patients with lactose intolerance. Population and methods. A total of 138 subjects aged 3 to 15 years were included. They underwent serial measurements of the waist circumference and hydrogen levels in the breath every 30 minutes over 3 hours during the hydrogen breath test. Results. Out of the entire sample, 35 (25.4%) patients had lactose intolerance. An increase of 0.85 cm in waist circumference compared to the baseline waist circumference results in a sensitivity of 88% and a specificity of 85% to predict lactose intolerance (odds ratio: 42.14, 95% confidence interval: 13.08-135.75, p < 0.001). The body mass index and waist circumference measurement did not affect abdominal distension (p= not significant); however, age modified the time of distension. Conclusions. A 0.85 cm increase in waist circumference compared to the baseline waist circumference during the hydrogen breath test is a useful parameter for the diagnosis of lactose intolerance in pediatrics. Variations in relation to body mass index and waist circumference did not affect the usefulness of an increased waist circumference, unlike age.
Descritores: Testes Respiratórios
Circunferência da Cintura
Intolerância à Lactose/diagnóstico
-Estudos Transversais
Valor Preditivo dos Testes
Hidrogênio/análise
Limites: Seres Humanos
Pré-Escolar
Criança
Adolescente
Tipo de Publ: Estudo Comparativo
Estudo Observacional
Responsável: AR94.1 - Centro de Información Pediatrica


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Id: lil-233845
Autor: Nogueira, Maria S; Mota, Helvécio C; Campos, Carlos A; Campos, Letícia L.
Título: Medidas dos fatores de conversäo H*(d)/Ka pra feixes de raios-X diagnóstico / Measure of H*(d)Ka conversion for Diagnostic X-rays fields
Fonte: In: Schiabel, Homero; Slaets, Annie France Frère; Costa, Luciano da Fontoura; Baffa Filho, Oswaldo; Marques, Paulo Mazzoncini de Azevedo. Anais do III Fórum Nacional de Ciência e Tecnologia em Saúde. Säo Carlos, s.n, 1996. p.514-514, graf.
Idioma: pt.
Conferência: Apresentado em: Fórum Nacional de Ciência e Tecnologia em Saúde, 3 e Congresso Brasileiro de Engenharia Biomédica, 15 e Congresso Brasileiro de Físicos em Medicina , 6 e Congresso Brasileiro de Informática em Saúde, 5 e Encontro Brasileiro de Proteçäo Radiológica, Campos do Jordäo, 13-17 out. 1996.
Resumo: Este trabalho apresenta os resultados da determinação experimental dos coeficientes de conversão da grandeza de calibração kerma no ar para a nova grandeza da ICRU de monitoração de área, H*(d). As medidas foram realizadas nas profundidades 10, 50 e 60 mm de uma esfera de PMMA de 30 cm de diâmetro em feixes de raios-X de radiodiagnóstico.
Descritores: Calibragem
Radiografia
Eletrodos
Hidrogênio
-Dose de Radiação
Fótons
Responsável: BR1.1 - BIREME
BR1.1/3012.37


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Id: biblio-1021461
Autor: Soo, Chiu-Shyan; Yap, Wai-Sum; Hon, Wei-Min; Ramli, Norhayati; Md Shah, Umi Kalsom; Phang, Lai-Yee.
Título: Co-production of hydrogen and ethanol by Escherichia coli SS1 and its recombinant
Fonte: Electron. j. biotechnol;30:64-70, nov. 2017. ilus, graf, tab.
Idioma: en.
Projeto: Fundamental Research Grant Scheme.
Resumo: Background: The development of a potential single culture that can co-produce hydrogen and ethanol is beneficial for industrial application. Strain improvement via molecular approach was proposed on hydrogen and ethanol co-producing bacterium, Escherichia coli SS1. Thus, the effect of additional copy of native hydrogenase gene hybC on hydrogen and ethanol co-production by E. coli SS1 was investigated. Results: Both E. coli SS1 and the recombinant hybC were subjected to fermentation using 10 g/L of glycerol at initial pH 7.5. Recombinant hybC had about 2-fold higher cell growth, 5.2-fold higher glycerol consumption rate and 3-fold higher ethanol productivity in comparison to wild-type SS1. Nevertheless, wild-type SS1 reported hydrogen yield of 0.57 mol/mol glycerol and ethanol yield of 0.88 mol/mol glycerol, which were 4- and 1.4-fold higher in comparison to recombinant hybC. Glucose fermentation was also conducted for comparison study. The performance of wild-type SS1 and recombinant hybC showed relatively similar results during glucose fermentation. Additional copy of hybC gene could manipulate the glycerol metabolic pathway of E. coli SS1 under slightly alkaline condition. Conclusions: HybC could improve glycerol consumption rate and ethanol productivity of E. coli despite lower hydrogen and ethanol yields. Higher glycerol consumption rate of recombinant hybC could be an advantage for bioconversion of glycerol into biofuels. This study could serve as a useful guidance for dissecting the role of hydrogenase in glycerol metabolism and future development of effective strain for biofuels production.
Descritores: Etanol/metabolismo
Escherichia coli/metabolismo
Hidrogênio/metabolismo
Hidrogenase/metabolismo
-Recombinação Genética
Biodegradação Ambiental
Meios de Cultura
Escherichia coli/enzimologia
Alcalinização
Fermentação
Glucose/metabolismo
Glicerol/metabolismo
Hidrogenase/genética
Responsável: CL1.1 - Biblioteca Central


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Id: biblio-1017382
Autor: Mamimin, Chonticha; Prasertsan, Poonsuk; Kongjan, Prawit; O-Thong, Sompong.
Título: Effects of volatile fatty acids in biohydrogen effluent on biohythane production from palm oil mill effluent under thermophilic condition
Fonte: Electron. j. biotechnol;29:78-85, sept. 2017. tab, graf, ilus.
Idioma: en.
Projeto: Khon Kaen University; . Thailand Research Fund.
Resumo: Background: Biohydrogen effluent contains a high concentration of volatile fatty acid (VFA) mainly as butyric, acetic, lactic and propionic acids. The presence of various VFAs (mixture VFAs) and their cooperative effects on two-stage biohythane production need to be further studied. The effect of VFA concentrations in biohydrogen effluent of palm oil mill effluent (POME) on methane yield in methane stage of biohythane production was investigated. Results: The methane yield obtained in low VFA loading (0.9 and 1.8 g/L) was 15­20% times greater than that of high VFA loading (3.6 and 4.7 g/L). Butyric acid at high concentrations (8 g/L) has the individual significantly negative effect the methane production process (P b 0.05). Lactic, acetic and butyric acid mixed with propionic acid at a concentration higher than 0.5 g/L has an interaction significantly negative effect on the methanogenesis process (P b 0.05). Inhibition condition had a negative effect on both bacteria and archaea with inhibited on Geobacillus sp., Thermoanaerobacterium thermosaccharolyticum, Methanoculleus thermophilus and Methanothermobacter delfuvii resulting in low methane yield. Conclusion: Preventing the high concentration of butyric acid, and propionic acid in the hydrogenic effluent could enhance methane production in two-stage anaerobic digestion for biohythane production.
Descritores: Propionatos/metabolismo
Butiratos/metabolismo
Águas Residuais/microbiologia
Metano/biossíntese
-Propionatos/análise
Butiratos/análise
Óleo de Palmeira
Methanobacteriaceae
Archaea
Methanomicrobiaceae
Geobacillus
Fermentação
Águas Residuais/análise
Hidrogênio
Anaerobiose
Responsável: CL1.1 - Biblioteca Central


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Id: biblio-1009654
Autor: Soo, Chiu-Shyan; Yap, Wai-Sum; Hon, Wei-Min; Ramli, Norhayati; Md Shah, Umi Kalsom; Phang, Lai-Yee.
Título: Improvement of hydrogen yield of ethanol-producing Escherichia coli recombinants in acidic conditions
Fonte: Electron. j. biotechnol;26:27-32, Mar. 2017. tab, ilus, graf.
Idioma: en.
Projeto: Fundamental Research Grant Scheme; . Science and Technology Research Grant.
Resumo: Background: An effective single culture with high glycerol consumption and hydrogen and ethanol coproduction yield is still in demand. A locally isolated glycerol-consuming Escherichia coli SS1 was found to produce lower hydrogen levels under optimized ethanol production conditions. Molecular approach was proposed to improve the hydrogen yield of E. coli SS1 while maintaining the ethanol yield, particularly in acidic conditions. Therefore, the effect of an additional copy of the native hydrogenase gene hycE and recombinant clostridial hydrogenase gene hydA on hydrogen production by E. coli SS1 at low pH was investigated. Results: Recombinant E. coli with an additional copy of hycE or clostridial hydA was used for fermentation using 10 g/L (108.7 mmol/L) of glycerol with an initial pH of 5.8. The recombinant E. coli with hycE and recombinant E. coli with hydA showed 41% and 20% higher hydrogen yield than wild-type SS1 (0.46 ± 0.01 mol/mol glycerol), respectively. The ethanol yield of recombinant E. coli with hycE (0.50 ± 0.02 mol/mol glycerol) was approximately 30% lower than that of wild-type SS1, whereas the ethanol yield of recombinant E. coli with hydA (0.68 ± 0.09 mol/mol glycerol) was comparable to that of wild-type SS1. Conclusions: Insertion of either hycE or hydA can improve the hydrogen yield with an initial pH of 5.8. The recombinant E. coli with hydA could retain ethanol yield despite high hydrogen production, suggesting that clostridial hydA has an advantage over the hycE gene in hydrogen and ethanol coproduction under acidic conditions. This study could serve as a useful guidance for the future development of an effective strain coproducing hydrogen and ethanol.
Descritores: Etanol/metabolismo
Escherichia coli/metabolismo
Hidrogênio/metabolismo
-Biotecnologia
Proteínas Recombinantes
Clostridium/genética
Clostridium/metabolismo
Escherichia coli/enzimologia
Escherichia coli/genética
Fermentação
Glicerol
Concentração de Íons de Hidrogênio
Hidrogenase/genética
Hidrogenase/metabolismo
Responsável: CL1.1 - Biblioteca Central


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Id: biblio-1009757
Autor: Matsakas, Leonidas; Gao, Qiuju; Jansson, Stina; Rova, Ulrika; Christakopoulos, Paul.
Título: Green conversion of municipal solid wastes into fuels and chemicals
Fonte: Electron. j. biotechnol;26:69-83, Mar. 2017. ilus, graf, tab.
Idioma: en.
Resumo: Presently, the society is facing a serious challenge for the effective management of the increasing amount of produced municipal solid wastes. The accumulated waste has caused a series of environmental problems such as uncontrolled release of greenhouse gases. Moreover, the increasing amount of wastes has resulted in a shortage of areas available for waste disposal, resulting in a nonsustainable waste management. These problems led to serious public concerns, which in turn resulted in political actions aiming to reduce the amount of wastes reaching the environment. These actions aim to promote sustainable waste management solutions. The main objective of these policies is to promote the recycling of municipal solid waste and the conversion of waste to energy and valuable chemicals. These conversions can be performed using either biological (e.g., anaerobic digestion) or thermochemical processes (e.g., pyrolysis). Research efforts during the last years have been fruitful, and many publications demonstrated the effective conversation of municipal solid waste to energy and chemicals. These processes are discussed in the current review article together with the change of the waste policy that was implemented in the EU during the last years.
Descritores: Resíduos Sólidos
Gerenciamento de Resíduos/métodos
Fontes Geradoras de Energia
-Digestão Anaeróbia
Pirólise
Eliminação de Resíduos
Cidades
Etanol
Meio Ambiente
Biocombustíveis
Hidrogênio
Metano
Tipo de Publ: Revisão
Responsável: CL1.1 - Biblioteca Central


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Id: lil-45236
Autor: Schneider, Roberto E; Pineda, Oscar.
Título: Alteración de la microbiota intestinal, determinada por la concentración de hidrogeno espirado en niños guatemaltecos / Change of the intestinal microbiotic determined by the expired hydrogen concentration in children of Guatemala.
Fonte: s.l; s.n; ene.-jun. 1985. 5 p. tab.
Idioma: es.
Descritores: Carboidratos/administração & dosagem
Carboidratos/metabolismo
Intestinos/microbiologia
Hidrogênio/metabolismo
-Carboidratos
Limites: Seres Humanos
Masculino
Feminino
Criança
Responsável: BR1.1 - BIREME
BR1.1/464.00


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Id: biblio-875691
Autor: Oliveira, Aryane Mota; Amorim, Norma Candida dos Santos; Amorim, Eduardo Lucena Cavalcante de; Salomon, Karina Ribeiro.
Título: Two phases fermentative process for hydrogen and methane production from cassava wastewater / Processo fermentativo em duas fases para a produção de hidrogênio e metano a partir da manipueira
Fonte: J. Health Biol. Sci. (Online);5(2):137-141, abr-jun /2017. ilus, graf.
Idioma: en.
Resumo: Introduction: Hydrogen and methane production was investigated in two phases of fermentative process. Objective: At the acidogenic phase, an anaerobic fluidized bed reactor was fed with cassava wastewater producing hydrogen. Methods: Expanded clay was used as a support material for biomass immobilization. The reactor was operated with HRT ranging from 8-1 h. Results: The best hydrogen yield production was 1.91 mol H2/mol glucose at HRT of 2 h. At the methanogenic phase, the acidogenic process effluent fed a fixed-bed reactor producing methane. Conclusion: Sururu (Mytella falcata) shells was used as support acted as pH neutralizer in the fixed-bed reactor, yielding best (0.430±0.150 Lmethane/gCOD) with 12h HRT phase. (AU)

Introdução: A produção de hidrogênio e metano foi avaliada em um processo fermentativo de duas fases. Objetivo: Na fase acidogênica, um reator anaeróbio de leito fluidificado foi alimentado com manipueira para a produção de hidrogênio. Métodos: Argila expandida foi utilizada com material suporte para a adesão microbiana. O reator foi operado com TDH, variando entre 8-1h. Resultados: O melhor rendimento de produção de hidrogênio foi 1.91 mol, H2/mol glicose em TDH de 2 h. Na fase metanogênica, o efluente do processo acidogênico alimentou um reator de leito fixo para a produção de metano. Conclusão: Conchas de Sururo (Mytella falcata) foram utilizadas como suporte, atuando como neutralizador do pH no reator de leito fixo, melhor rendimento (0.430±0.150 Lmethane/gDQO) na fase com TDH de 12h. (AU)
Descritores: Manihot
-Fermentação
Hidrogênio
Tipo de Publ: Artigo Clássico
Responsável: BR1780.2


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Id: biblio-875567
Autor: Silva, Deivid Sousa; Cunha-Santino, Marcela Bianchessi da; Marques, Elineide Eugenio.
Título: Decomposição e dinâmica de liberação de nitrogênio e fósforo de frações vegetais de Salvinia auriculata Aubl em um reservatório da Amazônia legal / Decomposition and release dynamics of nitrogen and phosphorous from vegetal fractions of Salvinia auriculata Aubl in a Legal Amazon reservoir
Fonte: Acta sci., Biol. sci;33(1):21-29, Jan.- Mar. 2011. ilus, tab.
Idioma: pt.
Resumo: Este estudo teve como objetivo determinar os coeficientes de decomposição da parte submersa (PS) e aérea (PA) de Salvinia auriculata em duas profundidades da coluna de água (superfície e sedimento). Também visou avaliar o rendimento do processo de perda de massa assim como a evolução temporal dos teores de fósforo e nitrogênio. As macrófitas foram separadas em partes; em seguida, foram secas até peso constante. Os materiais vegetais foram depositados em sacos de decomposição e incubados no reservatório da UHE Lajeado, Tocantins. As análises dos resultados de perda de massa revelaram que não houve diferenças significativas entre os PA-sed e PA-sup (p > 0,05), entretanto, os PA-sed foram significativamente diferentes dos PS-sed (p < 0,05) e dos PS-sup (p < 0,01). Os PA-sed apresentaram k = 0,0102 dia-1 e as incubadas na superfície (PA-sup) um k = 0,0067 dia-1, os PS-sed apresentaram um k = 0,0027 dia-1 e os PS-sup um k = 0,0040 dia-1. Durante os primeiros dias de decomposição foram liberadas grandes concentrações de fósforo e nitrogênio pelo processo de lixiviação; a partir do 14º dia foi observada uma tendência de aumento nas concentrações de nitrogênio, fato provavelmente relacionado com o enriquecimento dos detritos pela biomassa microbiana.

This study aimed to determine the decomposition coefficients of the submerged (SP) and aerial part (AP) of S. auriculata at two different depths within water column (surface and sediment). It also quantified the decomposition yield of S. auriculata and the temporal changes of nitrogen and phosphorous content of the remaining biomass. The macrophytes were fractionated in parts and were dried in sequence until attaining constant weight. The litterbags with plant material were incubated in the reservoir of UHE Lajeado. The results of mass loss showed that there were no significant differences among the AP-sed and AP-sur (p > 0.05). However, the AP-sed was significantly different from SP-sed (p < 0.05) and SP-sur (p < 0.01). The AP-sed presented a decay coefficient (k) of 0.0102 day-1 and AP-sur a k of 0.0067 day-1. The SP-sed presented a k of 0.0027 day-1 and the SP-sur 0.0040 day-1. It was also noticed that during the first days of decomposition great amounts of nitrogen and phosphorous were solubilized. This event was related to the leachate process; from the 14th day of decomposition, an increasing trend was observed in nitrogen concentrations. This fact was probably related to detritus enrichment by microbial colonization.
Descritores: Digestão Aeróbia
Hidrogênio
Macrófitas
Fósforo
Responsável: BR513.2 - Editora da Universidade Estadual de Maringá


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Id: lil-794646
Autor: Yuan, Lijuan; Shen, Jianliang.
Título: Hydrogen, a potential safeguard for graft-versus-host disease and graft ischemia-reperfusion injury?
Fonte: Clinics;71(9):544-549, Sept. 2016. tab.
Idioma: en.
Resumo: Post-transplant complications such as graft-versus-host disease and graft ischemia-reperfusion injury are crucial challenges in transplantation. Hydrogen can act as a potential antioxidant, playing a preventive role against post-transplant complications in animal models of multiple organ transplantation. Herein, the authors review the current literature regarding the effects of hydrogen on graft ischemia-reperfusion injury and graft-versus-host disease. Existing data on the effects of hydrogen on ischemia-reperfusion injury related to organ transplantation are specifically reviewed and coupled with further suggestions for future work. The reviewed studies showed that hydrogen (inhaled or dissolved in saline) improved the outcomes of organ transplantation by decreasing oxidative stress and inflammation at both the transplanted organ and the systemic levels. In conclusion, a substantial body of experimental evidence suggests that hydrogen can significantly alleviate transplantation-related ischemia-reperfusion injury and have a therapeutic effect on graft-versus-host disease, mainly via inhibition of inflammatory cytokine secretion and reduction of oxidative stress through several underlying mechanisms. Further animal experiments and preliminary human clinical trials will lay the foundation for hydrogen use as a drug in the clinic.
Descritores: Antioxidantes/uso terapêutico
Doença Enxerto-Hospedeiro/prevenção & controle
Hidrogênio/uso terapêutico
Transplante de Órgãos/efeitos adversos
Traumatismo por Reperfusão/prevenção & controle
-Citocinas/análise
Estresse Oxidativo/efeitos dos fármacos
Complicações Pós-Operatórias/prevenção & controle
Reprodutibilidade dos Testes
Limites: Animais
Tipo de Publ: Revisão
Responsável: BR1.1 - BIREME



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