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71.
This paper develops the methodological foundations of agrolandscape-environmental studies and management of agricultural land that are based on the concept of conservation and reproduction of land and other natural resources used in agriculture, soil fertility, productive longevity of agro-ecosystems and agrolandscapes (All-Russian Williams Fodder Research Institute), and the concept of the ecological framework of agricultural landscapes and ecological–economic balance (Moscow State University, Institute of Geography Russian Academy of Sciences). An integrative understanding of the essence of agricultural lands allows us to consider them as natural agricultural systems, which have a specific structure, functions, and links and are interrelated with other agrogeo-ecosystems and geo-ecosystems that form the environment. They supply agricultural products and other side derivatives of their functioning that are associated with the development of negative processes outside their limits. The features of study, construction, and management of agricultural land are determined by the dual nature-productive essence of agrogeo-ecosystems and the presence of three subsystems in them (abiotic, biotic, and anthropogenic). A special role is played by a control and monitoring unit. Agrogeoecosystems are characterized by the presence of three types of relationships (substance-energy, informational, and management); three main functions of agrogeo-ecosystems (productive, environment-forming, and nature-protective); the ability of agrogeo-ecosystems to respond to anthropogenic impacts; the ability of adaptation and recovery; and their distinctive openness and dynamism. The priorities of studies and management of agricultural land are formulated in several principles (systematic approach, emergence, environmental framework, landscape-ecological balance, multilevel and multifactor adaptation, etc.). They are intended to improve the adaptability, sustainability, productivity, and resource-saving and environmental role of agro-ecosystems and agricultural landscapes, which is only possible by creating favorable conditions for their functioning, ensuring a balance between the productive and protective agro-ecosystems and favorable conditions for the development of soil and soil biota, for the active life of major soil-formers (perennial grasses and microbes).  相似文献   
72.
The antioxidant activity of dihydroquercetin (DHQ) complexes with zinc, copper(II) and calcium was studied in vitro in blood plasma of healthy donors. The state of lipid peroxidation (LPO) in blood plasma was assessed by the content of malondialdehyde (MDA), diene (DC) and triene (TC) conjugates. The effect of DHQ and the complexes on the activity of the catalase enzyme in blood plasma was determined. It was found that DHQ complex with zinc ion reduces the MDA content in blood plasma by 14.9% compared with the control, which is twice as high as for DHQ (7.5%). The corresponding parameters of DHQ complexes with copper(II) and calcium ions were 11.2 and 3.7%, respectively. The effect of the complexes on the decrease in the DC and TC content in blood plasma compared with the control is comparable with the corresponding parameters for DHQ. The DHQ complex with zinc ion increases the catalase activity by 1.5% compared with DHQ. The complexes containing copper(II) and calcium ions increase the catalase activity no more than DHQ.  相似文献   
73.
NAD+-dependent formate dehydrogenase (FDH) was hydrophobized with palmitoyl chloride to give the samples with various modification degrees (2–10). The native and modified FDHs were comparatively studied in the system of reverse micelles of Aerosol OT in octane. Like the native, the modified enzyme displayed three maxima in the curve of dependence of its catalytic activity on the degree of surfactant hydration (the micelle size), which reflect the enzyme functioning in the form of a monomer, dimer, or octamer. The peak corresponding to the functioning of the FDH dimer was found to decrease along with an increase in the modification degree. Thus, the modified enzyme mainly functions in the form of monomer and octamer. The modified FDH displayed membranotropy and revealed the dependence of catalytic activity on surfactant concentration.  相似文献   
74.
75.
Population and family samples of two morphological forms (mutant and normal with respect to dorsal color) of parthenogenetic lizard species Darevskia armeniaca were examined by means of DNA fingerprinting using M13 mini- and (GACA) n and (TCC) n microsatellite DNA markers. The morphological forms examined were characterized by clonally inherited, species-specific patterns of the DNA markers, which were different from the species-specific DNA fingerprints of the other parthenogenetic species of the genus Darevskia (D. dahli, D. unisexualis, and D. rostombekovi). The mean index of similarity (S) obtained for a sample of 36 individuals from three isolated populations using three types of DNA markers was 0.966. This was similar to those observed in D. dahli (0.962) (P > 0.05), but higher than that in D. unisexualis (0.950) (P < 0.05) and D. rostombekovi(0.875) (P < 0.01). Inheritance of M13 minisatellite and (TCC) n microsatellite DNA markers in the F1 offspring of parthenogenetic lizards was examined. It was shown that variability and clonal diversity of the fingerprint phenotypes observed in the populations and families of D. armeniaca could be at least partly explained by RFLP mutations in microsatellite repeats.  相似文献   
76.
77.
The functions of interhemispheric EEG coherence were analyzed in 12 healthy subjects with the right individual profile of motor and sensor asymmetry and 7 subjects with the left profile in 2 experimental conditions: the state of rest and photostimulation of the central visual field. It was shown that in the rest condition the right-handed subjects have the higher values of EEG coherence in the thetal band in symmetrical frontal and central areas than the left-handed. These differences decreased for the frontal and central areas during activation caused by photostimulation but increased in the theta 2 and betal bands in symmetrical temporal areas (the coherence in the left-handed being higher). The difference in the EEG coherence between conditions was greater for the frontal and central areas in the right-handed than in the left-handed, especially, for the theta 1 and theta 2 bands. These findings suggest that the left-handed subjects have a less developed hierarchy of subcortical control of the functional state shifts than the right-handed.  相似文献   
78.
The authors show the role of hepatobiliscintigraphy (HBSG) in cholelithiasis as a screening technique in evaluating the patency of the common bile duct, which allows cholecystectomy to be performed if there are normal values, without resorting to additional studies. They have reprospectively analyzed the results of clinical and instrumental studies in 101 patients with cholelithiasis and obstructive jaundice of various etiology in whom the diagnosis was verified by endoscopic cholangiopancreatography (ERCPG). The sensitivity, specificity, and diagnostic efficiency of the scintigraphic technique were 96.5, 36.3, and 86.1%, respectively. It is recommended that invasive diagnostic techniques, such as ERCPG and other direst X-ray contrasting methods, should be used after having a positive result of two techniques: ultrasonography and HBSG (in the above order).  相似文献   
79.
NAD(+)-dependent formate dehydrogenase (FDH) was hydrophobized with palmitoyl chloride to give the samples with various modification degrees (2-10). The native and modified FDHs were comparatively studied in the system of reverse micelles of Aerosol OT in octane. Like the native, the modified enzyme displayed three maxima in the curve of dependence of its catalytic activity on the degree of surfactant hydration (the micelle size), which reflect the enzyme functioning in the form of a monomer, dimer, or octamer. The peak corresponding to the functioning of the FDH dimer was found to decrease along with an increase in the modification degree. Thus, the modified enzyme mainly functions in the form of monomer and octamer. The modified FDH displayed membranotropy and revealed the dependence of catalytic activity on surfactant concentration.  相似文献   
80.
The efficiency of the transfer of gamma-emitting radionuclides in food chains, including macrophytes, zoobenthos, and bentho- and ichthyophagist fish, was estimated in the radiation-polluted region of the Yenisei river. Significant differences in the efficiency of the transfer of natural and technogenic radionuclides between components of different trophic levels were revealed. Substantial species-related differences in the accumulation of radionuclides in ichthyophagist fish from food were revealed.  相似文献   
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