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1.
Three tests are routinely done to assess blood status of selenium in cattle: serum selenium, whole blood selenium, and glutathione peroxidase. The objective of this study was to compare the various analytical methods for determining blood selenium status in groups of mature cows and beef calves. Twenty to 30 blood samples per herd were collected from 8 beef herds in central Alberta and 1 dairy in Alberta herd twice a year from the spring of 1992 through the fall of 1995, and once from 185 spring calves in 2 beef herds in Saskatchewan. Serum and whole blood samples were submitted to 1 laboratory and whole blood samples were submitted to a 2nd laboratory. Samples for glutathione peroxidase determinations were submitted to a 3rd laboratory. Pearson's correlation coefficients and Cohen's kappa were calculated for each possible comparison among the different measures. The best agreement was observed between serum and whole blood analysis within Laboratory A. The remaining comparisons reflected poor agreement. Comparison of herd-level assessment resulted in better agreement than comparison of individual sample results among laboratories and procedures for all combinations tested. Serum selenium analysis was the only laboratory procedure for which external reference material was utilized. Serum selenium, whole blood selenium, and glutathione peroxidase measure different compartments of the blood selenium pool. The time frame of interest, supplementation practices, and the stability of recent dietary intake determine the optimum assessment method for individual animals or herds. Determination of the serum status or of blood selenium is more consistently measured at the herd-level than for individual samples.  相似文献   
2.
Immune Thrombocytopenia (ITP) is an autoimmune disease characterized by autoantibodies-mediated platelet destruction, a prevalence of M1 pro-inflammatory macrophage phenotype and an elevated T helper 1 and T helper 2 lymphocytes (Th1/Th2) ratio, resulting in impairment of inflammatory profile and immune response. Macrophages are immune cells, present as pro-inflammatory classically activated macrophages (M1) or as anti-inflammatory alternatively activated macrophages (M2). They have a key role in ITP, acting both as effector cells, phagocytizing platelets, and, as antigen presenting cells, stimulating auto-antibodies against platelets production. Eltrombopag (ELT) is a thrombopoietin receptor agonist licensed for chronic ITP to stimulate platelet production. Moreover, it improves T and B regulatory cells functions, suppresses T-cells activity, and inhibits monocytes activation. We analyzed the effect of ELT on macrophage phenotype polarization, proposing a new possible mechanism of action. We suggest it as a mediator of macrophage phenotype switch from the M1 pro-inflammatory type to the M2 anti-inflammatory one in paediatric patients with ITP, in order to reduce inflammatory state and restore the immune system function. Our results provide new insights into the therapy and the management of ITP, suggesting ELT also as immune-modulating drug.  相似文献   
3.
Due to the toxicity associated with the exposure to organochlorine pesticides, new materials capable of selectively capturing and detecting these compounds are highly desirable. In this study, imprinted polymers were prepared using three organochlorine pesticides—dieldrin (DE), endosulfan (EN), or hexachlorobenzene (HCB) as templates. The MIPs were polymerized via precipitation polymerization. The yields were over 90% with particle sizes ranging from 62 to 214 nm. Binding studies combined with GC‐ECD analysis showed that each template is more selective to its corresponding MIP compared with the other two structurally homologous templates. These results were consistent with those obtained using UV–vis where more bromocresol green (BCG) dye was released when higher template concentrations were introduced to the corresponding BCG‐impregnated MIPs. Since unique selectivity response pattern for each of the MIPs was obtained, this demonstrated that the MIPs were selective and can be potentially used in dye‐displacement array sensing. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44401.  相似文献   
4.
With 32 lactating Holstein cows we evaluated physiological effects of gossypol and cyclopropenoid fatty acids in diets containing 18.5% whole cottonseed (dry matter) based on corn, corn silage, and soybean meal. All cows consumed a control diet for the first 2 wk of lactation and then were assigned to either control or whole cottonseed diet for the remainder of their lactation. Milk production, milk fat and protein percentages, and daily dry matter intake were measured. Dry matter intakes were less for cows consuming the whole cottonseed diet, but net energy intake was similar for all diets. Milk fat from cows consuming whole cottonseed contained detectable concentrations of cyclopropene fatty acids. Total lipid in plasma, total serum cholesterol, serum gossypol, and apparent liver gossypol concentrations were greater in cows fed whole cottonseed. Gossypol and cyclopropenoid fatty acids appeared to be absorbed from the gut of cows fed whole cottonseed. Small amounts of gossypol in serum and liver tissue and small amounts of cyclopropene fatty acids in adipose tissue lipids and milk fat indicate a need to elucidate the significance of these physiologically active compounds in the human diet and their biological effects on lactating dairy cows.  相似文献   
5.
The purpose of this paper is to assess the applicability of two artificial neural networks (ANN) architecture, perceptron ANN, modular ANN, and Adam’s equation in the modeling of fatigue failure in polymer composites, more specifically in glass fiber reinforced plastic (GFRP). In the application of the model using ANN we show the feasibility of obtaining good results with a small number of SN curves. The other model used involves applying empirical equations known as Adam’s equations. A comparative study on the application of the aforementioned models is developed based on statistical tools such as correlation coefficient and mean square error. For this analysis we used composite materials in the form of laminar structures with distinct stacking sequences, which are applied industrially in the construction of large reservoirs. Reinforcements consist of mats and bidirectional textile fabric made of E-glass fibers soaked in unsaturated orthophthalic polyester resin. These were tested for six different stress ratios: R = 1.43, 10, ?1.57, ?1, 0.1, and 0.7. The results showed that although ANN modeling is in the initial phase, it has great application potential.  相似文献   
6.
Software Quality Journal - Quality requirements (QRs) are a key artifact needed to ensure the quality and success of a software system. Despite their importance, QRs rarely get the same degree of...  相似文献   
7.
8.
This paper presents a graphics system called the prism network and its boundary (PNB) aimed at representing the stratified solids that are formed in the subsurface terrain. It allows full 3D modelling of these types of spaces formed by superimposed layers bounded by stratification surfaces. A set of boreholes in the ground is used to generate a network of prisms that models the solid space and serves as the basis for creating two secondary networks, one of triangles and another of quadrilaterals, which define the model boundaries. This graphics system has been implemented in C++, using the standard OpenGL graphics API. The paper first defines and implements a model in the PNB data structure, the process by means of which it is generated is then described, and, finally, a range of applications to specific cases is presented and graphically illustrated.  相似文献   
9.
A novel scheme is formulated to control the dc link current of a current source inverter induction motor (CSIM) drive which greatly enhances the current response with substantial benefits on the overall dynamic performance of the drive. In addition to conventional closed-loop control with a PI regulator, the novel scheme incorporates a function generator to compensate for the motor back-EMF seen by the dc link. Application of this scheme to an indirect field-oriented CSIM drive is presented, and improvement in the drive performance is documented.  相似文献   
10.
描述了一种使用HTS/AuMEMS 开关电容器阵的低插损电子调谐式滤波器。同步将每个谐振器的电容值以相同变化量变化,两极滤波器就得到调谐。单极谐振器在3500~5000之间的K 系数得到了证明。在77K 平均Q 值为7000 时的总调谐范围大约为25%。  相似文献   
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