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151.
Sun (Chrysanthemum morifolium) and shade (Spathiphyllum wallisii) plants were used to study the effects of the inhibitors antimycin A and n-propyl gallate on photosynthesis, using chlorophyll fluorescence imaging. Photochemical efficiency in sun and shade plants was not inhibited by antimycin A under low light intensity, but the effective PS II quantum yield was inhibited under high illumination and heat, more so in sun than in shade species. The inhibitor n-propyl gallate had no or little effect on photochemical efficiency under low or high illumination and heat in control plants of both species. However, in stressed plants the effect of n-propyl gallate under high illumination and heat increased, strongly inhibiting the effective PS II quantum yield in S. wallisii. In addition to the effects produced by the inhibitors, changes were also observed by immunoblot analysis in the plastidial NADH DH complex, PTOX and PGR5. The quantities of PTOX and NDH-H subunit of the thylakoidal NADH DH complex and the NADH DH activity in the thylakoid membranes were similar in control plants of both species and increased in stressed plants, particularly in S. wallisii. However, the level of PGR5 polypeptide increased in C. morifolium but remained similar to control in S. wallisii. The results indicate that under high illumination and heat the cyclic electron flow around the PSI antimycin A-sensitive is important for the photosynthetic function in the sun species while another pathway involving the NADH DH complex and PTOX might be more important in the shade species. 相似文献
152.
C Zavala N E Morton D C Rao J M Lalouel I A Gamboa A Tejeda R Lisker 《Human heredity》1979,29(6):325-333
Complex segregation analysis was applied to a sample of 12,293 nuclear families each with at least 1 diabetic patient. The families were divided into two groups depending on the proband's treatment: insulin-dependent (IDG) and insulin-independent (IIG). Heterogeneity analysis has revealed a highly significant difference in the IIG group when families were divided into different mating types. The higher recurrence risk was found in the group with affected mothers. Also evidence for a major recessive gene was found in the IGG group, while it was not possible to distinguish between the hypothesis for absence of a major locus and absence of polygenic inheritance in the IDG group. Risks to develop the disease were calculated for a few typical situations. 相似文献
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Sergio Ivn Agudelo Carlos Federico Molina
scar Andrs Gamboa Juan David Surez 《Biomédica : revista del Instituto Nacional de Salud》2021,41(1):87
IntroducciónEl 50% de los episodios de sepsis neonatal se originan en la comunidad, con un gran porcentaje de mortalidad y complicaciones.ObjetivoEstimar los costos directos de la hospitalización por infección neonatal adquirida en la comunidad en neonatos a término con bajo riesgo al nacer.Materiales y métodosSe utilizó la perspectiva del tercer pagador y la técnica de microcosteo; el horizonte de tiempo fue la duración de la hospitalización. La determinación de las situaciones generadoras de costos se obtuvo por medio de un consenso de expertos y se cuantificaron con base en la factura detallada de la atención de 337 neonatos hospitalizados. Los costos de los medicamentos se calcularon con base en el Sistema de Información de Precios de Medicamentos (SISMED) y, el de los procedimientos, según los manuales tarifarios ISS 2001 con porcentaje de ajuste y el seguro obligatorio de accidentes de tráfico (SOAT). Para incorporar la variabilidad de la información en la estimación, se obtuvo una distribución de los costos usando el método de bootstrapping.ResultadosSe incluyeron las facturas por la atención de 337 recién nacidos. El promedio de costos directos de la atención por paciente fue de COL$ 2’773.965 (desviación estándar, DE=$ 198.813,5; IC95%: $ 2’384.298 - $ 3’163.632). Las principales categorías generadoras de costos fueron la internación en la unidad de cuidados intensivos y las tecnologías en salud. Los costos siguieron una una distribución logarítmica normal (log-normal).ConclusionesLas categorías con mayor impacto en los costos fueron la internación en la unidad neonatal y las tecnologías en salud. Los costos se ajustaron a una distribución logarítmica normal.Palabras clave: sepsis neonatal, costos y análisis de costo, recién nacido, unidades de cuidado intensivo neonatal, mortalidad infantil 相似文献
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Maria Rivera-Ch Alfredo Gamboa Fabiola Léon-Velarde Jose-Antonio Palacios David F O'Connor Peter A Robbins 《Journal of applied physiology》2003,94(3):1263-8; discussion 1253-4
Sea-level (SL) natives acclimatizing to high altitude (HA) increase their acute ventilatory response to hypoxia (AHVR), but HA natives have values for AHVR below those for SL natives at SL (blunting). HA natives who live at SL retain some blunting of AHVR and have more marked blunting to sustained (20-min) hypoxia. This study addressed the question of what happens when HA natives resident at SL return to HA: do they acclimatize like SL natives or revert to the characteristics of HA natives? Fifteen HA natives resident at SL were studied, together with 15 SL natives as controls. Air-breathing end-tidal Pco(2) and AHVR were determined at SL. Subjects were then transported to 4,300 m, where these measurements were repeated on each of the following 5 days. There were no significant differences in the magnitude or time course of the changes in end-tidal Pco(2) and AHVR between the two groups. We conclude that HA natives normally resident at SL undergo ventilatory acclimatization to HA in the same manner as SL natives. 相似文献
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