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1.
Copper malabsorption in coeliac disease   总被引:1,自引:0,他引:1  
Copper uptake during three hours from an oral test dose of copper sulphate solution giving three mg Cu++, close to the recommended daily dietary intake, was significantly reduced in patients with proximal intestinal disease, compared with normal subjects. Three out of ten patients had abnormal and otherwise unexplained blood counts compatible with the known haematological effects of copper deficiency and were restored to normal levels on a gluten-free diet. Copper deficiency and proximal intestinal disease should be suspected in patients with otherwise unexplained anaemia, especially neutropenia.  相似文献   
2.
The accepted model of color naming postulates that 11 “basic” color terms representing 11 common perceptual experiences show increased processing salience due to a theorized linkage between perception, visual neurophysiology, and cognition. We tested this theory, originally proposed by Berlin and Kay in 1969. Experiment 1 tested salience by comparing unconstrained color naming across two languages, English and Vietnamese. Results were compared with previous research by Berlin and Kay, Boynton and Olson, and colleagues. Experiment 2 validated our stimuli by comparing OSA, Munsell, and newly rendered “basic” exemplars using colorimetry and behavioral measures. Our results show that the relationship between the visual and verbal domains is more complex than current theory acknowledges. An interpoint distance model of color‐naming behavior is proposed as an alternative perspective on color‐naming universality and color‐category structure. © 2003 Wiley Periodicals, Inc. Col Res Appl, 28, 113–138, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/col.10131  相似文献   
3.
Donor CD4+ and CD8+ T cells mediate graft-vs.-leukemia (GVL) responses in the allogeneic bone marrow transplantation (alloBMT) setting. To evaluate the role of functional T cell subsets in the mediation of GVL, alloreactive donor CD4+ (Th1/Th2) and CD8+ (Tc1/Tc2) T cells of defined cytokine phenotype were generated by in vitro culture. A leukemia/transplantation model (B6 into B6C3F1; 1050 cGy host irradiation) was established using the bcr/abl-transfected myeloid leukemia line, 32Dp210 (P210; H-2k). Leukemia control mice (1X10(4) P210 cells per recipient) died at day 12.0 post-BMT. Recipients of the CD4+, Th1-type or CD8+, Tc1-type populations were conferred a survival advantage (death at 20.7 and 23.5 days post-BMT, respectively). In contrast, the CD4+, Th2-type population did not mediate GVL (death at 12.3 days). Furthermore, cell mixing experiments demonstrated that the Th2 subset abrogated both Th1- and Tc1-mediated GVL. The CD8+, Tc2 population, which secreted type II cytokines and lysed the P210 leukemia target in vitro, mediated GVL in some experiments; interestingly, the magnitude of Tc2-mediated GVL was inversely related to the level of interleukin-10 (IL-10) secreted in vitro by the Tc2 population. These studies therefore indicate that alloreactive T cells of type I phenotype maximally generate GVL, and that type I/type II interactions are an important consideration for allogeneic transplantation in the setting of leukemic hosts.  相似文献   
4.
Yellowfin tuna enhance their hunting success in the vast pelagic environment by using their sense of smell to detect intact (uninjured) prey that are beyond visual range. However, the olfactory cues that tuna use would normally face huge and rapid dilution in the open ocean. We demonstrate that these prey odors are complexed within biologically derived lipid structures that probably delay the dilution of the amino acids to subthreshold concentrations and provide persistent arousal and search cues for the tuna. This may be the first demonstration of an extracorporeal biological function for liposomes. Tuna may also form chemical search images to maximize feeding efficiency. We demonstrate that the amino acid profiles of various prey species are consistent over time and between schools, which makes the formation of search images feasible.  相似文献   
5.
The size distribution function of bubbles in thermodynamic equilibrium with the surrounding liquid has been derived in the absence of gravity. The derivation has been based on the assumption that the gas is dispersed into bubbles in a completely random way in respect of the energies of the bubbles. The size distribution function of bubbles obtained when surface tension effects are neglected is of the same form as the empirical Nukiyama-Tanasawa distribution, and gives also the size distribution function of droplets consisting of an incompressible liquid when the way the liquid is dispersed into droplets is assumed to be completely random with respect to the volumes of the droplets. The derived size distribution functions agree well with the experimental size distributions of bubbles in water having been generated by an air entrainment process at the surface of the water or behind a ventilated body.  相似文献   
6.
Since chromatographic separation is a dynamic process, with the interactions between the drug and the chiral stationary phase mediated by the solvent, no single interacting structure, such as could be found by minimizing the energy, could possibly describe and account for the ratio of residence times in the chromatographic column for the enantiomeric pair. We describe the use of explicit-solvent fully atomistic molecular dynamics simulations, permitting all the interactions between the atoms constituting the chiral stationary phase, solvent molecules and the drug molecule. This allows us to better understand the molecular dynamic chiral recognition that provides the discrimination, which results in the separation of enantiomers by high performance liquid chromatography. It also provides a means of predicting, for a given set of conditions, which enantiomer elutes first and an estimate of the expected separation factor. In this review, we consider the use of molecular dynamics toward this understanding and prediction.  相似文献   
7.
The purpose of this paper is to provide new insights on the connections that exist between the discontinuous Galerkin method (DG), the flux reconstruction method (FR) and the recently identified energy stable flux reconstruction method (ESFR) when solving time dependent conservation laws. All these schemes appear to be quite similar and it is important to understand how they are related. In this paper, we first review results on the stability of the discontinuous Galerkin method and extend it to the filtered discontinuous Galerkin method. We then consider the flux reconstruction approach and show its connections with DG. In particular, we show how the Energy Stable Flux Reconstruction method introduced by Vincent et al. is equivalent to a filtered DG method, hence giving a new proof of its stability. Also, it allows the use of the method without having to know the special form of the flux correction polynomials. Finally, we underline some fundamental differences that exist between FR and DG.  相似文献   
8.
For energetic flows there are many advantages of high order schemes over low order schemes. Here we examine a previously unknown advantage. It is commonly thought that the number of points per wavelength in order to obtain a given error in a numerical approximation depends only on runtime and the order of the approximation. Using truncation error arguments and examples we will show that it is not a constant and depends also on the wavenumber. This dependence on the numerical order and wavenumber strongly favors high order schemes for use in flows which have significant energy in the high modes such at Rayleigh–Taylor and Richtmyer–Meshkov instabilities.  相似文献   
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