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331.
We experienced three cases of primary mediastinal yolk sac tumor which were resected after 6 courses of BEP chemotherapy with G-CSF support. All cases had high levels of AFP. CT scan revealed an anterior mediastinal tumor infiltrating the surrounding tissue in all cases, and multiple pulmonary nodules in one case. The serum AFP level decreased markedly, but did not return to normal after the chemotherapy was completed. The markedly decreased mediastinal tumor masses were removed with en-bloc resection of the lung and pericardium. Viable tumor cells were not present in the resected tumors. These three cases remain free of disease at present, 3 years, 9 months and 5 months after operation.  相似文献   
332.
Various polymeric materials were combusted in a small-scale box model equipped with an air supply system to determine the evolution of toxic gases and evaluate the toxicity of the environment containing these gases. There were cases where concentrations of HCN, acrolein and formaldehyde were higher in terms of potential toxicity than that of CO. Overall experimental results indicate that small-scale experiments are useful in evaluating combustion toxicity of materials.  相似文献   
333.
The relationships among tissue edema, lactate accumulation, and intracellular pH in middle cerebral artery (MCA)-occluded rats were investigated with multiecho 1H magnetic resonance imaging and spatially resolved metabolic images constructed by 1H and 31P nuclear magnetic resonance (NMR) chemical shift imaging (CSI). For the effective and sensitive detection of NMR signals from the brain, outer volume suppression (OVS), reduced k-space sampling and proton irradiation were incorporated into the CSI sequences. The consecutive three measurements of calculated T2 image, lactate image, and pH image which were required for 3.75 h were repeated for four cycles of 1-16 h after MCA occlusion. Tissue edema and lactate accumulation in the infarcted region were gradually and consistently increased during the 15-h observation period. In contrast, severe acidosis was already detected on the first pH image (2-4.7 h after MCA occlusion); thereafter, the degree of acidosis became milder and showed no further progression. The dissociation between the time courses of the lactate accumulation and pH decrease was clearly demonstrated by the NMR metabolic images. Acid-base balance in cerebral infarction might be affected not only by lactate production but also by complicated interactions with tissue edema and some other factors.  相似文献   
334.
335.
A technique for separating 4 nonionic, 7 anionic and 4 amphoteric surfactants with n-dodecyl groups was studied by high performance liquid chromatography (HPLC) and applied to the determination of these surfactants in commercial shampoos and household detergents. Conditions used for the separation were: column packing and size, TSK-LS 410 (5μ) and 6 mm i.d. × 500 mm (2 connected, 250 mm columns); mobile phase, water/methanol (25/75, v/v) containing 0.25 M sodium perchlorate adjusted to pH 2.5 with phosphoric acid; column temp., 50 C; detector, RI. Surfactants in shampoos and detergents were clearly distinguished from each other and determined without column chromatographic pretreatment, e.g., ion-exchange chromatography.  相似文献   
336.
A monoclonal antibody against methamphetamine (MA-3 mAb) was found to be strongly bound to ephedrine. This feature was quite different from that of other fourteen mAbs against MA. Analyses of cDNA sequence and steric conformation by molecular modeling revealed that one hydrophilic pocket was generated in the heavy chain of MA-3 mAb involving CDRH-1 and CDRH-2. Asn33, Asn35, Asn50 and Asp52 were the main components of the unique pocket capable of binding to the hydroxyl group of ephedrine.  相似文献   
337.
The thermal diffusivity of a polyamide mesh having plane wave structure was determined by a temperature wave analysis method developed in our laboratory. The measured thermal diffusivity of the polyamide mesh represents the combined result for the polyamide fiber part and the open space of the mesh. The polyamide mesh was measured in air and liquid paraffin conditions. Its effective thermal diffusivity was obtained as a function of the volume content of the surrounding material. A unit-cell model was applied to the polyamide mesh structure and shows good correspondence with the experimental results.  相似文献   
338.
We have studied the atomic geometries and the electronic properties of benzene/metal interfaces by using density functional theoretical (DFT) calculations with van der Waals corrections. Adsorption energies of benzene on Cu(111), Ag(111), and Au(111) surfaces calculated by van der Waals density functional proposed by Dion and co-workers agree reasonably well with experimentally reported values, while those calculated by a semi-empirical van der Waals correction proposed by Grimme are overestimated slightly. The work function change induced by benzene adsorption on the three surfaces are quite well reproduced by the semi-empirical correction, suggesting that weak adsorption geometries can be quite well reproduced by DFT with a semi-empirical dispersion correction scheme.  相似文献   
339.
This letter reports on the averaging effect on prediction errors of the fast automated demand response (FastADR) power limitation amount calculated by our autoregressive and neural net models for a large number of multi‐type building air‐conditioning facilities. The standard deviation of prediction error variation decreases with the number of FastADR trials according to the rule. This result will be useful for estimating the averaging effect in the prediction of FastADR for a large number of target facilities. © 2016 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.  相似文献   
340.
RNase H is an enzyme that specifically cleaves RNA hybridized to DNA. The enzyme is ubiquitously present in various organisms. Single bacterial and eucaryotic cells often contain two RNases H, whereas single archaeal cells contain only one. To determine whether there is a physiological significance in the ubiquity and multiplicity of the enzyme, and whether all enzymes are evolutionarily diverged from a common ancestor, we carried out phylogenetic analyses of the RNase H sequences. In this report, we demonstrated that RNases H are classified into two major families, Type 1 and Type 2 RNases H, of which only the Type 2 enzymes are present in all living organisms, including bacteria, archaea, and eucaryotes, suggesting that they represent an ancestral form of RNases H. Based on this information, we discuss the evolutionary relationships and possible cellular functions of RNases H.  相似文献   
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