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991.
Metabonomic analysis is a powerful tool for identifying and characterizing metabolic disorders, for example type 2 diabetes and the metabolic syndrome. Nuclear magnetic resonance (NMR) spectroscopy is an essential tool for such analysis, with special benefits. The review assesses the current status and potential of NMR-based metabonomics of type 2 diabetes. The horse is proposed as a possible model for studying this condition and disease. Some examples are shown of horse blood analyses by NMR.  相似文献   
992.
In this paper, we study (α,β)-metrics of scalar flag curvature on a manifold M of dimension n (n 〉 3). Suppose that an (α,β)-metric F is not a Finsler metric of Randers type, that is, F ≠k1 V√α^2 + k2β^2 + k3β, where k1 〉 0, k2 and k3 are scalar functions on M. We prove that F is of scalar flag curvature and of vanishing S-curvature if metric. In this case, F is a locally Minkowski and only if the flag curvature K = 0 and F is a Berwald metric.  相似文献   
993.
通过对60例非胰岛素依赖型糖尿病患者和40例健康对照者血浆葡萄糖、血浆胰岛素、糖化血红蛋白,血清和红细胞中锌、钙、镁的检测发现,糖尿病组与对照组比较,血清镁和红细胞镁、锌较低,红细胞钼较高,且这些微量元素的变化与血浆区区糖、血胰岛素。糖化血红蛋白等相关。  相似文献   
994.
With the help of an improved mapping approach and a linear-variable-separation approach, a new family of exact solutions with arbitrary functions of the (2+1)-dimensional Nizhnik-Novikov-Veselov system (NNV) is derived. Based on the derived solutions and using some multi-valued functions, we find a few new folded solitary wave excitations for the (2+1)-dimensional NNV system.  相似文献   
995.
Proteins of camel's milk and shubat were studied by electrophoresis. Their microelement compositions were determined. Electrophoresis showed two bands in camel's milk and several in shubat. It was found that Fe and Zn occur in greater quantities in both camel's milk and shubat than in cow's milk.  相似文献   
996.
通过引入几个较大空气轴,设计了几种全反射光子晶体光纤(toatl internal reflection photonic fiber).运用平面波展开法(plane-wave expansion method)和频域有限差分方法(finite-difference frequency—domain method)对它们的约束模式、有效折射率和归一化频率等特性进行了分析.结果表明当第一圈填充率(d/A)改变时其约束模式、有效折射率和归一化频率有明显的变化,对设计低损耗光纤有一定的作用.  相似文献   
997.
ABSTRACT A novel ion-pair palladium(Ⅱ) compound, (NOzBzPy)2[Pd(dmit)2] (NO2BzPy^+ = 1-(4-nitrobenzyl)pyridinium, dmit^2- = 2-thioxo-1,3-dithiole-4,5-bis(thiolate)), was synthesized and characterized by single-crystal X-ray structure determination. This compound crystallizes in the monoclinic system, space group P21/n with a = 10.4463(11), b = 8.5627(9), e = 20.017(2)A, β = 97.7730(10)°, V = 1774.1(3)A^3, Z = 2, C30H22N4O4S10Pd, Mr = 929.52, Dc = 1.740 g/cm^3,μ = 1.155 mm^-1, S = 1.006, F(000) = 936, R = 0.0354 and wR = 0.0675. The most intriguing general structural feature of the compound is the completely segregated columnar stacks of anions and cations. There exist hydrogen-bonding interactions within the cation column.  相似文献   
998.
A novel glucose biosensor has been fabricated and employed as the amperometric detector of a capillary electrophoresis (CE) system. (±)-1-Ferrocenylethylamine and chitosan were successively modified on a 500-µm diameter disc platinum electrode by dip-coating. The modified electrode was subsequently immersed in glucose oxidase (GOx) solution to entrap the enzyme in the chitosan membrane. The primary amino groups of 1-ferrocenylethylamine, GOx, and chitosan were cross-linked by glutaraldehyde to obtain a biosensing membrane so as to reduce leaching of 1-ferrocenylethylamine and GOx. The electrochemical behavior of the target biosensor was investigated. It was demonstrated that the investigated biosensor features fast response, high stability, long lifetime, and ideal compatibility with the CE system. When CE was employed to introduce a glucose plug into the surface of the biosensor, the current response was linear to the glucose concentration in the range of 0.0025 to 2.5 mM with a detection limit of 1.2 µM (S/N = 3) at a working potential of +0.6 V (vs. SCE). The CE-biosensor system was applied to the determination of the glucose level in human serum. The results were satisfactory and in good agreement with the hospital assay results.  相似文献   
999.
The analysis of plasma samples from healthy, diabetic and nephropathic subjects was carried out by 2D gel electrophoresis. This approach shows clear differences among the three classes of subjects. In the case of diabetic and nephropathic patients intense spots appear. Their enzymatic digestion followed by matrix assisted laser desorption ionization/mass spectrometry (MALDI/MS) analysis shows that an overexpression of unglycated and glycated ApoA-I is present in both pathological states. Interestingly, this trend is also observed for the retinol-binding protein (RBP). The data obtained can be relevant to assess possible risks associated either with the glycation level of ApoA-I or with the overexpression of RBP. In fact, in the former case possibly a different functionality of the glycated protein is to be expected, reflecting a different efficiency in cholesterol transport. In the latter case, the increase of RBP level can be related to the overweight of the diabetic subjects under investigation: it is known that obesity leads to RBP overexpression. In the case of nephropathic patients, the RBP level increases in parallel with serum creatinin.  相似文献   
1000.
SA (sulfamic acid) catalyzes the reaction of indole with aldehyde and ketone to afford bis(indol-3-yl)methanes in good to excellent yields under solvent-free condition at ambient temperature.  相似文献   
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