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961.
Eurasian Soil Science - The results are presented of modeling the “contour water flooding” biotechnology aimed at cleaning heavily petroleum-polluted agrosoddy-podzolic soils (Albic...  相似文献   
962.
Eurasian Soil Science - Carbon isotope ratios in soil organic matter are often used in paleoecological research for reconstructing climate and plant communities (type of photosynthesis). The...  相似文献   
963.
Eurasian Soil Science - The distribution of total organic matter (Corg), particulate organic matter (CPOM), and potentially mineralizable organic matter (C0) in mega- (10–5 and 5–2 mm),...  相似文献   
964.
Eurasian Soil Science - Quantitative characteristics of microbial communities in southern agrochernozems of the Stavropol region managed with the use of no-till technology and moldboard plowing...  相似文献   
965.
Are  M.  Kauer  K.  Kaart  T.  Selge  A.  Astover  A.  Reintam  E. 《Eurasian Soil Science》2020,53(5):619-631
Eurasian Soil Science - Soil formation on the human time scale is immensely time consuming, although it can be significantly accelerated through the effects of vegetation. The content of...  相似文献   
966.
Eurasian Soil Science - A method of the Holocene paleoenvironment reconstruction based on the analysis of pedobiomarkers in tell deposits is suggested. On the Yunacite tell, such a reconstruction...  相似文献   
967.
The current tuberculosis treatment regimen is long and complex, and its failure leads to relapse and emergence of drug resistance. One of the major reasons underlying the extended chemotherapeutic regimen is the ability of Mycobacterium tuberculosis to attain a dormant state. Therefore, the identification of new lead compounds with chemical structures different from those of conventional anti-tuberculosis drugs is essential. The compound 3-(phenethylamino)demethyl(oxy)aaptamine (PDOA, 1), isolated from marine sponge of Aaptos sp., is known as an anti-dormant mycobacterial substance, and has been reported to be effective against the drug resistant strains of M. tuberculosis. However, its target protein still remains unclear. This study aims to clarify the structure–activity relationship of 1 using 15 synthetic analogues, in order to prepare a probe molecule for detecting the target protein of 1. We succeeded in creating the compound 15 with a photoaffinity group that retained antimicrobial activity, which proved to be a suitable probe molecule for identifying the target protein of 1.  相似文献   
968.
Portfolio theory, an established technique in the selection of stocks and financial instruments for investment purposes, was used as a means of selecting an economic mix of veterinary interventions in a dairy herd. The expected return on investment in six veterinary services and the associated standard deviations (as measures of risk) were calculated using computer simulation modeling techniques. Mathematical programming techniques were applied to identify the optimal combinations of veterinary interventions which maximize expected financial returns while minimizing risk. Parametric analysis was used to show how risk (standard deviation) increases as the required expected return is increased along the efficient risk-return frontier of these optimal combinations. This exercise emphasizes the importance of regarding risk in addition to expected return when considering investment in veterinary services.  相似文献   
969.
Tissue concentrations of LH as determined by radioimmunoassay (RIA) may not accurately measure actual changes that could occur in biological activity of the hormone. To examine this possibility, pituitary homogenates from 135 beef cows in various physiological states were analyzed for content of LH by both RIA and an in vitro bioassay. The ratio of biological/immunological active concentrations of LH remained constant (.52 +/- .02) even though tissue concentrations of immunoactive LH differed among groups. Tissue concentrations of bioactive LH were linearly related to, and highly correlated with (P less than .001), tissue concentrations of immunoactive LH. These data indicate that only a fraction of the immunoactive LH in the bovine pituitary is biologically active. However, this fraction does not vary with the reproductive status or plane of nutrition.  相似文献   
970.
Staphylococcus aureus and coagulase-negative staphylococci (CNS) isolated from bovine mastitis were examined for their ability to interact with 125I-labelled fibronectin, fibrinogen and type II collagen. Their relative surface hydrophobicity and production of extracellular capsule were also investigated. Almost all S. aureus strains bound fibronectin (mean value 23%), fibrinogen (mean value 12%) and type II collagen (mean value 16%). CNS bound fibronectin (mean value 6%) and type II collagen (mean value 7%), but not fibrinogen (mean value 2%). The specificity of binding of these proteins to S. aureus strain F1440 and to coagulase-negative Staphylococcus chromogenes strain BO52 was studied by adding an excess of unlabelled proteins. Fibronectin and collagen binding were observed to be specific, varying between 50 and 75%, whereas the specificity of fibrinogen binding to S. aureus strain F1440 was lower (26%). Most of the S. aureus strains (63%) showed very high surface hydrophobicity (autoaggregation) or lower hydrophobicity (29% of the strains) and the rest were hydrophilic. None of the CNS strains autoaggregated, 44% were classified as hydrophilic strains. Hydrophilic strains (except the reference strains) did not show extracellular capsule production. However, the encapsulated (reference) strains showed low binding to these proteins as compared to their unencapsulated variants. Pre-treatment of S. aureus strain F1440 and S. chromogenes strain BO52 with trypsin decreased their fibronectin binding capacity and surface hydrophobicity, whereas pre-treatment with bovine milk (except on collagen binding to strain F1440) did not significantly affect binding to these proteins. These data indicate that S. aureus and CNS isolated from bovine udder infection have the ability to bind to tissue matrix and plasma proteins which may be exposed in the traumatized or toxin-damaged udder epithelial lesions.  相似文献   
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