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751.
Kolosova AIu Samsonova ZhV Egorov AM Shevaleva SA Orlova NG Kiseleva TV Khotimchenko SA Tutel'ian VA 《Voprosy pitaniia》1999,68(1):23-27
The method of solid-phase enzyme linked immunosorbent assay (ELISA) for quantitative detection of chloramphenicol (CAP) in milk was developed. Peculiarities of the adsorption on the microtitre plates surface of CAP-ovalbumin conjugate were investigated. Different conditions of competition stage of the analysis were studied. Conditions providing CAP monitoring in human blood serum in the clinical range were optimized. Matrix effect on the assay results was studied. The specificity of the analytical system was investigated and the reagents stability was examined. The method developed permits CAP concentration to be determined in human blood serum, diluted 1/100, in the linear range from 0.1 to 100 ng/ml. The assay is characterized by high sensitivity (0.08 ng/ml) and good reproducibility (CV < 10.8%), assay time is about 3 hours. The correlation coefficient with HPLC is 0.977. 相似文献
752.
Tutel'ian VA Kravchenko LV Lashneva NV Avren'eva LI Guseva GV Sorokina EIu Chernysheva ON 《Voprosy pitaniia》1999,68(5-6):9-12
The rats were fed with albuminous concentrate from the genetically modified soybean 40-3-2 ("Monsanto Co", USA) 1.25 g/rat/day for 5 months. Their blood, urea and liver were investigated to measure total protein and glucose levels, aminotransferase and alkaline phosphatase activities, pH, relative density and creatinine level in the urea, as well as hepatic enzyme activity of the I and II phases of xenobiotic metabolism, and the whole and non-sedimentated lysosomal enzyme activities. The lasting albuminous concentrate supplementation from the genetically modified soybean to the rat's diet has been shown to modify hepatocyte membrane function and enzymatic activity within physiological standards. It was not harmful to the adaptation systems. 相似文献
753.
The ends of a coped beam are commonly connected to the web of a girder by double clip angles. The clip angles may either be bolted or welded to the web of the beam. One of the potential modes for the failure of the clip angle connection is the block shear of the beam web material. To investigate the strength and the behavior of the block shear of coped beams with welded end connections, ten full-scale coped beam tests were conducted. The test parameters included the aspect ratio of the clip angles, the web shear and tension area around the clip angles, the web thickness, beam section depth, cope length, and connection position. The test results indicated that the specimens failed, developing either tension fractures of the web near the bottom of the clip angles or local web buckling near the end of the cope. Although the final failure mode of the six specimens was local web buckling, it was observed during the tests that these specimens exhibited a significant deformation of the block shear type prior to reaching their final failure mode. No shear fracture was observed in all of the tests. A comparison between the ultimate loads in the test and the predictions using the current design equations indicates that the current design standards such as the AISC-LRFD, CSA-S16-01, Eurocode 3, BS5950-1:2000, AIJ and GB50017, are inconsistent in predicting the block shear strength of coped beams with welded end connections. The analytical study of the strength of the test specimens using the finite element method, a parametric study, and a proposed design model for designing block shears for coped beams with welded clip angles are included in a companion paper. 相似文献
754.
It is established that fish products in the consumers' market of Primorye not always correspond to the required parameters of quality and safety. Deflections of fish products quality were defined by organoleptic properties, nutritional and energetic value of about 46.3% of examined samples. Till 25.8% of examined samples of fish products fell short of microbiological parameters of standard safety. 相似文献
755.
Pogozheva AV Derbeneva SA Anykina NV Kondakova NM Kulakova SN Medvedev FA Mal'tsev GIu Trushina EN Mustafina OK Pozdniakov AL Gadzhieva ZM 《Voprosy pitaniia》2007,76(6):28-32
The investigation of influent of antiatherosclerotic diets with shark liver oil on clinical and metabolic parameters in patients with cardiovascular diseases. Results of the study show that enrichment of a diets with shark liver oil in patients with ischemic heart disease and hypertension improved clinic status, antropometric levels, lipid spectrum of blood and immunology status. The mechanism of shark liver oil was investigated in rats. 相似文献
756.
The efficiency of iodine containing cultured milk products (yoghurts) has been studied in complex of therapy measures in patients with pus processes in soft tissues. Introduction of yoghurts with Laminariajaponica additives to dietary intake for surgical patients with iodine deficiency favors its severity degree decreasing, protective forces of organism increasing and rapid wound healing introduction of yoghurts. 相似文献
757.
Material yielding is typically modeled either by plastic zone or plastic hinge methods under the context of geometric and material nonlinear finite element methods. In fire analysis of steel structures, the plastic zone method is widely used, but it requires extensively more computational efforts. The objective of this paper is to develop the nonlinear material model allowing for interaction of both axial force and bending moment, which relies on the plastic hinge method to achieve numerical efficiency and reduce computational effort. The biggest advantage of the plastic-hinge approach is its computational efficiency and easy verification by the design code formulae of the axial force-moment interaction yield criterion for beam-column members. Further, the method is reliable and robust when used in analysis of practical and large structures. In order to allow for the effect of catenary action, axial thermal expansion is considered in the axial restraint equations. The yield function for material yielding incorporated in the stiffness formulation, which allows for both axial force and bending moment effects, is more accurate and rational to predict the behaviour of the frames under fire. In the present fire analysis, the mechanical properties at elevated temperatures follow mainly the Eurocode 3 [Design of steel structures, Part 1.2: Structural fire design. European Committee for Standisation; 2003]. Example of a tension member at a steady state heating condition is modeled to verify the proposed spring formulation and to compare with results by others. The behaviour of a heated member in a highly redundant structure is also studied by the present approach. 相似文献
758.
759.
Tutel'ian VA Filatov NN Sorokina EIu Chernysheva ON Salova NIa Sizykh EV Anisimova OV 《Voprosy pitaniia》2003,72(3):20-23
This paper presents results of a detection of genetically modified organisms (GMO) in food from the shops of Moscow. The screening methods and event-specific assay based on the polymerase chain reaction is used. Transgenic DNA from genetically modified soybeans line 40-3-2 is detected in 17.2% samples of studied foods. Soybeans line 40-3-2 is allowed in Russian food supply. 相似文献
760.
In 94 persons living in the Moscow region, with a body mass index >25 kg/m2 were identified on the polymorphism rs9939609 FTO gene. The results showed that 83% of them were carriers of the mutant allele, and 43%--contained the mutant allele in the homozygous state. Carriers of the mutant allele rs9939609 FTO gene were distinguished by higher absolute and relative values of fat mass and triglycerides in serum. 相似文献