RESUMEN
The objective of the present study was to characterize the effectiveness of the audiological and radiological diagnostic techniques as well as the results of the surgical treatment of the patients presenting with otosclerosis based at the hospital clinic of the Pacific State Medical University. The analysis included 49 surgical interventions for stapedoplasty carried out on 42 patients during the period from 2015 to 2017. The tympanic form of the disorder was diagnosed in 51.02% of the cases, the mixed form I in 16.28%, and the mixed form II in 32.7%. The excellent results within two months after surgery were obtained in 87.2% of the treated patients, the good and satisfactory results in 8.72% and 4.08% of them respectively.
Asunto(s)
Otosclerosis , Cirugía del Estribo , Estribo/diagnóstico por imagen , Hueso Temporal/diagnóstico por imagen , Adulto , Audiometría/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Otosclerosis/diagnóstico , Otosclerosis/epidemiología , Otosclerosis/fisiopatología , Otosclerosis/cirugía , Evaluación de Procesos y Resultados en Atención de Salud , Federación de Rusia/epidemiología , Estribo/patología , Cirugía del Estribo/métodos , Cirugía del Estribo/estadística & datos numéricos , Tomografía Computarizada por Rayos X/métodosRESUMEN
The donor-acceptor relation (DAR) in a plant under cold exposure to frost was studied in the plants of winter wheat (Triticum aestivum L.) Mironovskaya 808 cultivar and its allocytoplasmatic hybrid containing alien cytoplasm of goat grass (Aegilops ovata L.) and grown in a water culture until phenophase, from two leaves until branching. The alteration of DAR was processed by treatment of plant with solutions of diuron and paraquat the photosynthesis inhibitors, keeping plants in the dark, changing from mixotrophic to autotrophic nutrient, and also through the exchange of nutrient solution to distillate water. Determination of frost-resistance on the basis of survival percentage among frozen plants is more significant (R = 0.701-0.999) and related to the frost-resistance of leaves, the correlation P/Rd between speeds of true photosynthesis at light saturation (P) and plant dark respiration (Rd), the approximate speed of dry plant biomass alteration, the total content of water-soluble sugars, and the ratio of di- and monosaccharides (sucrose, glucose + fructose) in leaves. The importance of all the indexes mentioned above for acquiring resistance to low temperatures in plants is discussed in the present article.
Asunto(s)
Adaptación Psicológica/fisiología , Biomasa , Carbohidratos/biosíntesis , Dióxido de Carbono/metabolismo , Congelación , Triticum/fisiología , Quimera/fisiología , Fotosíntesis/fisiología , Solubilidad , Agua/metabolismoRESUMEN
This study is devoted to CO2 gas exchange (true photosynthesis at light saturation (P), dark respiration (R), and P/R ratio) in vegetating and cold-hardened winter wheat (Triticum aestivum L.) plants (cultivar Mironovskaya 808) in relation to their freezing tolerance. Under natural cultivation conditions, freezing tolerance of plants depended on adaptive changes in the shape of P and R curves in the temperature range from 20 to -2 degrees C. These changes, induced by cold hardening and treatment of plants with the photosynthesis inhibitor diuron, were observed within month and week ranges. Under laboratory conditions, the P/R ratio in vegetating plants increased three times within an hour range as the temperature decreased from 22 to 0 degree C. The P/R ratio also decreased within a minute range as a result of partial inhibition of photosynthesis with diuron and immediately decreased when CO2 concentration in the air was reduced from 419 to 0 microl/l. The P/R ratio decreased primarily at the expense of a decrease in P. The decrease in P/R was more pronounced at low temperatures, indicating variability of low-temperature tolerance of photosynthesis within a minute range. The possibility of plant adaptation to nonsimultaneous temperature changes under natural conditions via adaptive changes in temperature tolerance of the photosynthetic apparatus is discussed.
Asunto(s)
Aclimatación/fisiología , Congelación , Consumo de Oxígeno/fisiología , Fotosíntesis/fisiología , Triticum/fisiologíaRESUMEN
We studied the influence of alien cytoplasm of spring goatgrass Aegilops ovata L. on some physiological parameters in winter wheat (Triticum aestivum L.), Mironovskaya 808, under normal conditions and in the case of modified source-sink relations. Measurements of relative rates of plant dry matter growth and its distribution among organs, CO2 exchange (photosynthesis upon light saturation and dark respiration), content of sugars (sucrose + glucose + fructose) and their ratio in leaves, frost hardiness, and indices of membrane stability and damage of leaves by frost have shown that, on average, alloplasmic hybrid differed from the initial cultivar by almost all parameters. Reduced frost hardiness, increased index of leaf damage by frost, lowered leaf content of sugars, and reduced sucrose/(glucose + fructose) ratio in the alloplasmic hybrid were combined with higher roots/leaves ratio, relative rate of dry matter growth, and photosynthesis and respiration rates. The alloplasmic hybrid was more tolerant to decreased source strength in source-sink relations as compared to the initial cultivar.
Asunto(s)
Aclimatación/fisiología , Citoplasma/metabolismo , Triticum/crecimiento & desarrollo , Dióxido de Carbono/metabolismo , Quimera , Frío , Consumo de Oxígeno/fisiología , Fotosíntesis/fisiología , Sacarosa/metabolismoRESUMEN
Data on morphophysiological monitoring of winter wheat (Triticum aestivum L.) cultivar Mironovskaya 808 grown in Hoagland and Arnon solution in a greenhouse and transferred to natural conditions in March-April 2004 with the mean daily temperature of 0.6 +/- 0.7 degrees C within the exposure period of 42 days are presented. Water content, dry weight of plants and their organs, frost hardiness of plants, degree of tissue damage by frost, CO2 metabolism (photosynthesis and respiration), concentrations of sugars in tissues and proportions between different sugar forms, and activities of soluble and insoluble acid and alkaline phosphatases were monitored. Monitoring was carried out for three experimental variants simulating different microclimatic conditions in spring: after snow melting (experiment I), under ice crust (experiment II), and under snow cover (experiment III). Plants in experiments III and II demonstrated a higher water content in tissues, lower frost hardiness, higher rates of biomass loss, lower concentration of sugars and lower di- to monosaccharide ratio in tissues, and higher total invertase activity, particularly, cell wall-associated acid invertase activity. The dark respiration rates at 0 degrees C did not significantly differ between experimental variants. The photosynthetic capacity at this measurement temperature was maintained in all experimental variants being most pronounced in experiment II with the most intense photoinhibition under natural conditions. Comparison of experiments III and II with experiment I is used to discuss the negative effect of changes in certain microclimatic variables associated with global warming and leading to plant extortion and death from frost in spring.
Asunto(s)
Aclimatación , Clima , Estaciones del Año , Triticum/fisiología , Biomasa , Metabolismo de los Hidratos de Carbono , Dióxido de Carbono/fisiología , Ambiente Controlado , Fotosíntesis , Hojas de la Planta/fisiología , Raíces de Plantas/fisiología , Tallos de la Planta/fisiología , Temperatura , beta-Fructofuranosidasa/metabolismoRESUMEN
Long-term studies of the cytoplasm-nucleus interactions in alloplasmic hybrids with the nucleus of Triticum aestivum functioning in the alien cytoplasm of Aegilops ovata are reviewed. The interaction of heterologous genome and cytoplasm affects the balanced mechanisms of developmental control of the parental forms. The changes are observed at all levels of both physiological and morphological processes. Alloplasmic wheats produced by backcrossing represent a novel type of synthetic plant different from the T. aestivum type and of great interest to breeders.
Asunto(s)
Núcleo Celular/metabolismo , Quimera/crecimiento & desarrollo , Citoplasma/metabolismo , Poaceae/citología , Triticum/fisiología , Quimera/metabolismo , Frío , Morfogénesis , Triticum/genéticaRESUMEN
The capacity of plants for hibernation is ensured by the presence of significant food resources, like in hibernating mammals. In plants, these resources are accumulated in autumn due to maintenance of the rates of true CO2 assimilation elevated with reference to the dark respiration. This becomes possible as a result of higher thermoresistance of photosynthesis, as compared to respiration, and low light requirements for photosynthesis saturation at low positive or negative temperatures.