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Sapundzhiev E Pupaki D Zahariev P Georgiev G Ivanov I 《Journal of veterinary medicine. A, Physiology, pathology, clinical medicine》2007,54(9):499-500
The result of the histological diagnosis from postmortal investigation of the Indian elephant (Elephas maximus) uterus structure is presented in the current study. The rare anatomical finding showed altered nodular part from the uterus wall. Through conventional and histochemical staining neoplasmatic formations were determined and diagnosis Fibroleiomyoma was established, which should not be accepted as the prime cause for the animal's death. 相似文献
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G. N. Fedotov G. V. Dobrovol’skii V. I. Putlyaev A. V. Garshev V. K. Ivanov E. I. Pakhomov 《Eurasian Soil Science》2006,39(7):738-747
The colloidal structures in soils were studied by scanning and transmission electron microscopy. Small-angle neutron scattering was used in the pioneering study of the colloidal soil structures and their rearrangements under the effect of different factors. It was found that colloidal particles are fixed apart in a gel matrix formed by organic molecules. The results obtained suggest that the organomineral gel is composed of soil humus occurring, at least in part, in a gel-like status and reinforced by organic and inorganic colloidal particles. In the interaction with water, the reinforced humus gel behaves as many polymers: it swells, absorbing water and increasing in volume; it shrinks under drying conditions. Different impacts on the soil affect the status of the reinforced humus gel, which results in the observed changes of the soil properties. 相似文献
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Belobrov V. P. Yudin S. S. Yaroslavtseva N. V. Yudina A. V. Dridiger V. K. Stukalov R. S. Kluev N. N. Zamotaev I. V. Ermolaev N. R. Ivanov A. L. Kholodov V. A. 《Eurasian Soil Science》2020,53(7):968-977
Eurasian Soil Science - This article presents the results of research on the impact of no-till technology on the natural bulk density and macro- and microaggregate composition of the topsoil... 相似文献
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ZS Perényi O Szenci PV Drion H Banga-Mboko NM Sousa B El Amiri JF Beckers 《Reproduction in domestic animals》2002,37(6):324-329
Pregnancy‐associated glycoproteins (PAGs) isolated from the placenta of various ruminant species are enzymatically inactive members of the aspartic proteinase family. The measurement of these proteins in the maternal blood can be a good indicator of the presence of a live embryo. As certain aspartic proteinases are present in biological fluids in physiological and pathological conditions at various concentrations, it was necessary to determine the specificity of three radioimmunoassay (RIA) systems currently used for the detection of PAG molecules. Commercially available members of the aspartic proteinase family like pepsinogen, pepsin, chymosin, rennet, cathepsin D and renin were tested in a wide concentration range (10 ng/ml – 1 mg/ml). Pepsinogen cross‐reacted in RIA 1, RIA 2 and RIA 3 over 1 mg/ml, 50 μg/ml and 500 μg/ml concentrations, respectively. In the presence of pepsin, cross‐reaction was observed in RIA 1, RIA 2 and RIA 3 over 1 mg/ml, 500 μg/ml and 1 mg/ml concentrations, respectively. Chymosin and rennet could cross‐react in RIA 2 and RIA 3, while renin and cathepsin D did not decrease the binding of the tracer to antisera more, than that of the minimal detection limit. As the plasma/serum concentrations of the examined aspartic proteinases reported in the literature were outside the concentration range where cross‐reaction was observed, it can be concluded that these RIA systems were specific for the detection of PAGs in biological fluids. 相似文献
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The phenomenon of mineralization (biological mineralization) of organic matter in chernozems has been studied. A decrease
in the content of Corg with time can be considered an index of the organic matter mineralization. It is suggested that the humus horizons of modern
chernozems contain the pools of organic matter of different ages: easily decomposable organic matter, labile biologically
active humus, stable biologically active humus, and relatively inert humus. The composition and mean residence times of these
pools and their contribution to the total organic matter content have been estimated. The particular types of the biological
mineralization have been determined on the basis of the comparison between the velocities of mineralization (M) and humification
(H) processes: total unidirectional mineralization (M ≫ H), equilibrium mineralization (M ∼ H), nonequilibrium mineralization
(M> <H), and zero mineralization. The separation of subtypes is based on data on the relative rates (%) of the organic matter
mineralization. On the basis of available experimental data on chernozems buried under kurgans and in loess sediments (with
the age of up to 800 ka), the quantitative relationship of the humus content in the buried soils on their age has been found;
it has an exponential shape. During the first 100 ka after the soil burial, the soil humus content gradually (with a slowing
intensity) decreases from 100–75 to 6.5% of its content in the virgin chernozems. Then, 100–1000 ka after the soil burial,
the soil humus content remains approximately constant (6.5% of the initial level, or 0.3% of the soil mass). The rates of
mineralization have been estimated. It is shown that the elemental composition (C, H, N, O) of humic acids remains relatively
stable for a long time due to the regeneration of the chemical structure of humus (matric restoration of humus). It is suggested
that several different forms of humus related to pedogenesis should be distinguished in the biosphere. The renewable humus
in the equilibrium state with the environment is typical of the open biospheric (soil) systems. The fossil humus, whose content
decreases with time, and whose composition remains stable, is typical of the semiclosed and closed systems. With time, it
transforms into residual humus, whose content and composition remain stable. The fossilized organic matter in the fossil soils
and sediments of the past geological epochs (Mesozoic and Paleozoic) considerably differs from the renewable, fossil, and
residual humus. 相似文献
7.
Ivanov I. V. Prikhodko V. E. Zamotaev I. V. Manakhov D. V. Novenko E. Yu. Kalinin P. I. Markova L. M. Plaksina A. L. 《Eurasian Soil Science》2019,52(6):593-609
Eurasian Soil Science - The relationship between soil formation and sedimentation on the floodplain of the Utyaganka River (the Ural River basin) in the Arkaim Reserve (Chelyabinsk oblast, Southern... 相似文献
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