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1.
Bone marrow examination revealed a lipid-laden histiocytosis in seven patients undergoing long-term total parenteral nutrition necessitated by extensive short-bowel surgical resection. Clinical abnormalities occurred during this treatment which required bone marrow examination. These included hepatosplenomegaly and peripheral blood cytopenia; the median time to the detection of these abnormalities was 64 months. The most striking change within the bone marrow was the presence of many pigment-laden histiocytes which had the typical morphology of sea-blue histiocytes seen in the so-called idiopathic sea-blue histiocyte syndrome. The occurrence of sea-blue histiocytosis in the bone marrow in association with long-term parenteral nutrition for short-bowel syndrome has not, to our knowledge, been reported previously and should now be considered in the differential diagnosis of bone marrow sea-blue histiocytosis.  相似文献   
2.
In order to produce highly concentrated bioethanol by pervaporation using an ethanol‐permselective silicalite membrane, techniques to suppress adsorption of succinic acid, which is a chief by‐product of ethanol fermentation and causes the deterioration in pervaporation performance, onto the silicalite crystals was investigated. The amount adsorbed increased as the pH of the aqueous succinic acid solution decreased. The pervaporation performance also decreased with decreasing pH when the ternary mixtures of ethanol/water/succinic acid were separated. Using silicalite membranes individually coated with two types of silicone rubber, pervaporation performance was significantly improved in the pH range of 5 to 7, when compared with that of non‐coated silicalite membranes in ternary mixtures of ethanol/water/succinic acid. Moreover, when using a silicalite membrane double‐coated with the two types of silicone rubber, pervaporation performance was stabilized at lower pH values. In the separation of bioethanol by pervaporation using the double‐coated silicalite membrane, removal of accumulated substances having an ultraviolet absorption maximum at approximately 260 nm from the fermentation broth proved to be vital for efficient pervaporation. Copyright © 2005 Society of Chemical Industry  相似文献   
3.
In this article, a new method for measuring a total spectral radiance factor of a FWA‐treated sample illuminated by a specific standard illuminant is introduced. The method replaces an unstable real fluorescent standard by a bi‐spectral luminescent radiance factor data, which works as a virtual fluorescent standard (VFS) by knowing spectral intensity distributions of illuminations applied to the sample. The method utilizes two illuminations I1 and I2 whose relative spectral intensity distributions are different from each other and synthesizes a virtual illumination presenting the identical fluorescent spectral radiance factor to that presented by the standard illuminant with the VFS of the specific bi‐spectral luminescent radiance factor by linearly combining I1 and I2 with the suitable weighting factors. The applicability of the method is examined in principle by comparing ISO brightness and CIE whiteness index of fluorescent standard paper as a test sample obtained by this new method to the assigned values. © 2007 Wiley Periodicals, Inc. Col Res Appl, 32, 195–200, 2007  相似文献   
4.
The well-posedness problem (existence and uniqueness of solutions) of a class of multi-modal piecewise affine systems is addressed, where binary-switches individually act under autonomous switching. First, a new transition rule on the discrete state, called the switch-based transition rule, is introduced and some relations with the mode-based transition rule are discussed. Next, a sufficient condition for such a multi-modal system to be well-posed for all external inputs is derived in terms of well-posedness of its subsystems of lower complexity "bimodal systems". Finally, an easily checkable condition for the bimodal system to be well-posed for all external inputs is given, which consequently allows us to algebraically determine well-posedness of the multi-modal systems in question.  相似文献   
5.
The yeast Pseudozyma antarctica produces a large amount of glycolipid biosurfactants known as mannosylerythritol lipids (MELs), which show not only excellent surface‐active properties but also versatile biochemical actions. To investigate the biosynthesis of MELs in the yeast, we recently reported expressed sequence tag (EST) analysis and estimated genes expressing under MEL production conditions. Among the genes, a contiguous sequence of 938 bp, PA_004, showed high sequence identity to the gene emt1, encoding an erythritol/mannose transferase of Ustilago maydis, which is essential for MEL biosynthesis. The predicted translation product of the extended PA_004 containing the two introns and a stop codon was aligned with Emt1 of U. maydis. The predicted amino acid sequence shared high identity (72%) with Emt1 of U. maydis, although the amino‐terminal was incomplete. To identify the gene as PaEMT1 encoding an erythritol/mannose transferase of P. antarctica, the gene‐disrupted strain was developed by the method for targeted gene disruption, using hygromycin B resistance as the selection marker. The obtained ΔPaEMT1 strain failed to produce MELs, while its growth was the same as that of the parental strain. The additional mannosylerythritol into culture allowed ΔPaEMT1 strain to form MELs regardless of the carbon source supplied, indicating a defect of the erythritol/mannose transferase activity. Furthermore, we found that MEL formation is associated with the morphology and low‐temperature tolerance of the yeast. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
6.
Clinical receptology encompasses broad areas, including receptor or postreceptor defects due to mutations of receptor or other genes, abnormalities due to receptor antibodies and secondary changes of receptors under various pathological conditions. Recent progress in molecular biology has succeeded in cloning genes of receptors, G-proteins and other cellular proteins that are involved in the signal transduction and clarified their germ-line and somatic mutations. It is of importance that mutations of receptors and G-proteins do not necessarily cause loss of function but sometimes cause gain of function of receptors or G-proteins, thus leading to hyperfunction. Molecular basis that causes either loss or gain of function has been studied but is not completely understood. Some examples of gain of function mutatious of G-protein coupled receptors, tyrosin kinase-type receptors and G alpha protein are shown. Another important aspect in receptor research is that mutation of a single receptor gene sometimes result in different phenotypes and even different modes of inheritance. For example, mutations of rhodopsin (a G-protein coupled receptor) gene cause retinitis pigmentosa of autosomal dominant type and autosomal recessive type and also cause congenital stationary night blindness. Exact mechanisms responsible for such differences are not completely understood. There are polymorphisms in some genes that may be involved in some diseases. An example is a polymorphism in beta 3-adrenergic receptor that is claimed but not clearly demonstrated to be a cause of obesity or type II diabetes. Such polymorphism is possibly a gene in polygenic diseases. Receptology is important for elucidating pathogenesis of complex diseases.  相似文献   
7.
Hybrid bubble memory devices have been proposed and operated with the memory density of 4 Mbit/cm2. In the hybrid bubble memory devices, minor loops are composed of ion-implanted tracks with 4-µm period, and major lines and functional parts including block-replicate and swap gates are composed of Permalloy tracks with a longer period of 12 µm. Passive junctions between ion-implanted and Permalloy tracks have been developed, introducing the tapered ion-implantation technique. Improving the characteristics of the functional parts composed of Permalloy tracks, the hybrid bubble memory devices with block-replicate and swap gates have been operated, and the feasibility of the devices has been confirmed. In addition, the possibility of higher memory density has been shown.  相似文献   
8.
The inhibitory effect of sodium selenite on biliary secretion of methyl mercury was examined in rats. The biliary secretion of methyl mercury in rat treated with 1 mumol/kg of methyl mercury was significantly decreased by administration of selenite at doses of 0.05 mumol/kg or higher. In rats given 10 mumol/kg of methyl mercury, marked depression of biliary secretion of mercury was observed when selenite was injected at a dose of 0.2 mumol/kg. On the other hand, secretion of substantial amounts of selenium was observed when biliary secretion of mercury was depressed. When the concentration of selenium in the bile was higher than 5 nmol/ml, biliary secretion of mercury was markedly depressed independently of the dose of methyl mercury administered (1 mumol/kg or 10 mumol/kg). These results suggest that the degree of inhibitory effect of selenite may be determined by the selenium concentration in the liver or the bile after treatment with selenite rather than the molar ratio of the dose of methyl mercury and selenite. We concluded that the decrease in biliary secretion of methyl mercury induced by selenite may result from inhibition of pathway for secretion of methyl mercury from liver to bile rather than the direct formation of a complex between methyl mercury and selenium. Methyl mercury has been considered to be secreted from liver to bile as a complex with glutathione (GSH). However, administration of selenite did not affect biliary secretion of GSH or hepatic glutathione S-transferase activity. Moreover, gel filtration of liver cytosol demonstrated that the distribution pattern of hepatic methyl mercury between macromolecules and GSH was not significantly changed by administration of selenite. These results suggest that selenite does not affect complex formation of methyl mercury with GSH at least in the liver. Selenite might specifically inhibit the activity of the canalicular transporter(s) which transport complexes of methyl mercury and GSH from the liver to bile.  相似文献   
9.
Thirty-two patients with primary osteoarthritis of the medial compartment of the knee were studied prospectively to assess the relationship between clinical results, limb alignment, and adduction moment of the knee. Clinical and radiographic examination and gait analyses were performed preoperatively and repeated at 6 months and at 1, 3, and 6 years after high tibial osteotomy. The preoperative peak adduction moment was high in 25 patients and low in seven. In both groups, the adduction moment of the knee decreased at 6 months after surgery but increased after that period. Alignment of the affected knee in both groups remained valgus after surgery (average femorotibial angle, 167 degrees-169 degrees). Clinical outcome in both groups improved after surgery and remained unchanged after 1 year. The peak adduction moment of the knee for the whole group significantly correlated with alignment and foot angle before and 6 years after surgery but did not correlate with stride length and walking velocity. In addition, only alignment was associated significantly with clinical results at 6 years. These results suggest that the preoperative peak adduction moment of the knee does not correlate with clinical or radiographic outcomes of high tibial osteotomy, provided sufficient valgus alignment is achieved at surgery.  相似文献   
10.
A basidiomycetous yeast, Pseudozyma graminicola CBS 10092, was found to accumulate a large amount of glycolipids in the cultured medium when grown on soybean oil as the sole carbon source. Based on thin layer chromatography, the extracellular glycolipids gave spots corresponding to those of mannosylerythritol lipids (MELs), which are highly functional and promising biosurfactants. From the structural characterization by 1H and 13C NMR, the main product was identified as 4-O-[(4'-mono-O-acetyl-2', 3'-di-O-alka(e)noyl)-beta-D-mannopyranosyl]-D-erythritol, which is a highly hydrophilic derivative of MELs known as MEL-C. According to high-performance liquid chromatography analysis, the main product, MEL-C, comprised approximately 85% of all the MELs, and the total amount reached approximately 10 g/L for 7 days. The fatty acids of the present MEL-C consisted of mainly C6, C8 and C14 acids, considerably different from those of MEL-C produced by other Pseudozyma strains such as P. antarctica and P. shanxiensis. The observed critical micelle concentration (CMC) and the surface-tension at CMC of the MEL-C were 4.0 x 10(-6) M and 24.2 mN/m, respectively, while those of MEL-A, the most intensively studied MEL, were 2.7 x 10(-6) M and 28.4 mN/m, respectively. This implied that the MEL-C has higher hydrophilicity than conventional MELs hitherto reported. In addition, on a water-penetration scan, the MEL-C efficiently formed the lamella phase (Lalpha) at a wide range of concentrations, indicating its excellent self-assembling properties. From these results, the newly identified MELs produced by P. graminicola are likely to have great potential for use in oil-in-water type emulsifiers and/or washing detergents, and would thus facilitate a broad range of applications for the promising yeast biosurfactants.  相似文献   
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