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101.
102.
Micropigs are the most likely source animals for xenotransplantation. However, an appropriate method for evaluating the lung of micropigs had not been established. Therefore, this study was performed to evaluate the feasibility of 64-channel multi-detector row computed tomography (MDCT) to measure the diameter of the pulmonary arteries and the lung volume in micropigs. The mean diameters of the trachea, and left and right bronchi were 1.6 ± 0.17, 1.18 ± 0.14, and 1.1 ± 0.11 cm, respectively. The mean diameters of the main, right, and left pulmonary arteries were 1.38 ± 0.09, 1.07 ± 0.26, and 0.98 ± 0.13 cm and the diameters of right, left, and common inferior pulmonary veins were 0.97 ± 0.20, 0.76 ± 0.20, and 1.99 ± 0.26 cm, respectively. The mean lung volume was 820.3 ± 77.11 mL. The data presented in this study suggest that the MDCT may be a noninvasive, rapid, and accurate investigational method for pulmonary anatomy in living lung donors.  相似文献   
103.
Ionic conductivity and mechanical properties of a mixed polymer matrix consisting of poly(ethylene glycol) (PEG) and cyanoresin type M (CRM) with various lithium salts and plasticizer were examined. The CRM used was a copolymer of cyanoethyl pullulan and cyanoethyl poly(vinyl alcohol) with a molar ratio of 1:1, mixed plasticizer was ethylene carbonate (EC) and propylene carbonate (PC) at a volume ratio of 1:1. The conductive behavior of polymer electrolytes in the temperature range of 298∼338 K was investigated. The PEG/LiClO4 complexes exhibited the highest ionic conductivity of ∼10−5 S/cm at 25°C with the salt concentration of 1.5 M. In addition, the plasticized PEG/LiClO4 complexes exhibited improvement of ionic conductivity. However, their complexes showed decreased mechanical properties. The improvement of ionic conductivity and mechanical properties could be obtained from the polymer electrolytes by using CRM. The highest ionic conductivity of PEG/CRM/LiClO4/(EC-PC) was 5.33×10−4 S/cm at 25°C.  相似文献   
104.
Brucella infections in wildlife originate either from contact with infected livestock or from a natural sustainable reservoir in wildlife populations. As South Korea has set a goal of brucellosis eradication by 2013, it is necessary to determine the prevalence of Brucella in wildlife and wild rodents. This information will play an important role in the control of brucellosis. Because of the absence of prominent clinical signs, direct and indirect laboratory tests are essential for diagnosing brucellosis. In this study, tissue and blood samples were taken from wild animals, abandoned dogs, a cat and wild rodents, and they were tested for Brucella or Brucella-specific antibodies by isolation, PCR and serology. Results showed that 18.6% (33/177) of blood samples were positive by PCR, and 5.7% (11/194) were positive by C-ELISA. However, none of these samples yielded culturable bacteria. Of the tissue samples, 9.7% (8/82) were positive by PCR. Brucella was isolated from only one tissue culture from a Chinese water deer carcass. This Brucella species was identified as Brucella abortus biovar 1 by biotyping, 16S rRNA PCR and the Bruce-ladder PCR assay. In this study, we reported the prevalence of Brucella in wildlife, dogs, a cat and rodents by using serological and molecular methods, and we report the first isolation of B. abortus in wild Chinese water deer in South Korea.  相似文献   
105.
The correct identification of the geographical origin of deer antlers is essential to quality control, as its positive physiological effects correlate with chemical components. In this study, we applied both genomics and metabolomics to the origin-identification of 101 samples from Canada, New Zealand, and Korea. The genomics identified deer species in each country but failed to categorize all the samples, due to the presence of identical species in different countries. For identical species, NMR-based metabolomics gave clean separations, compounds specific to each country were identified, and the validity was confirmed by prediction analysis. As the genomics provided unambiguous read-outs for different species, and the metabolomics cleanly distinguished among identical species from different countries, their combined use could be a robust method for origin-identification even in difficult cases. We believe the method to be generally applicable to many herbal medicinal products for which various species are grown internationally.  相似文献   
106.
4(5)-Methylimidazole has received the attention of federal and state regulatory agencies because of its carcinogenicity and common presence in foods and beverages. In the present study, the formation of 4(5)-methylimidazole in Maillard reaction model systems consisting of D-glucose/NH(3), L-rhamnose/NH(3), methylglyoxal/NH(3), and methylglyoxal/formaldehyde/NH(3) was investigated. 4(5)-Methylimidazole was formed at levels ranging from 0.49 to 0.71 mg/mL in the d-glucose/NH(3) model system. The formation of 4(5)-methylimidazole was slightly higher in the L-rhamnose/NH(3) system (0.91 mg/mL) than in the d-glucose/NH(3) system (0.71 mg/mL) under the conditions used in the present study. A methylglyoxal/NH(3) system produced significantly higher levels of 4(5)-methylimidazole (5.70 mg/mL), suggesting that methylglyoxal is an important precursor of 4(5)-methylimidazole. Ammonolysis of methylglyoxal, which is one of the glucose degradation products, was proposed to form formamide, which subsequently reacted with 2-aminopropanal (α-aminocarbonyl intermediate) formed from methylglyoxal to give 4- or 5-methylimidazole. The levels of 4(5)-methylimidazole found in commercial cola soft drinks range from 0.30 μg/mL (brand 3) to 0.36 μg/mL (brands 1 and 5).  相似文献   
107.
108.
Two novel caffeoylmalic acid methyl esters, 2-O-(trans-caffeoyl)malic acid 1-methyl ester (6) and 2-O-(trans-caffeoyl)malic acid 4-methyl ester (7), were isolated from pear (Pyrus pyrifolia Nakai cv. Chuhwangbae) fruit peels. In addition, 5 known hydroxycinnamoylmalic acids and their methyl esters were identified: 2-O-(trans-coumaroyl)malic acid (1), 2-O-(cis-coumaroyl)malic acid (2), 2-O-(cis-coumaroyl)malic acid 1-methyl ester (3), 2-O-(trans-coumaroyl)malic acid 1-methyl ester (4), and 2-O-(trans-caffeoyl)malic acid (phaselic acid, 5). The chemical structures of these compounds were determined by spectroscopic data from ESI MS and NMR. Of all the isolated compounds, five hydroxycinnamoylmalic acids and their methyl esters (2-4, 6, 7) were identified in the pear for the first time.  相似文献   
109.
Land disposal of waste drilling fluid is an environmental concern because of the high salt content and the presence of potential toxic elements. A water-based drilling fluid was tested in a laboratory column study to determine the feasibility of leaching excessive salt without mobilizing chromium (Cr). The drilling fluid-affected two Alfisols with similar mineralogy, acidity, and texture were treated with gypsum (CaSO4 · 2H2O), calcium carbonate (CaCO3), or calcium phosphate (CaHPO4) (0 to 2% of weight). The electrical conductivity (EC) increased and the sodium adsorption ratio (SAR) decreased with increasing Ca-salt concentration. The pH did not vary significantly with the changes in the concentrations of gypsum and calcium phosphate. The pH of the mixtures increased in proportion to the concentration of added calcium carbonate. The hydraulic conductivity increased and the mobility of the soil particles decreased with increasing Ca-salt concentration. The Cr mobility decreased by gypsum and CaCO3 treatments but it increased by calcium phosphate treatment. The soil with a higher content of organic matter and cation exchange capacity (CEC) showed a higher hydraulic conductivity and lower Cr mobility than the other soils at the same levels of the treatment. The results of this study suggest that the amendment of drilling fluid-affected soils with CaCO3 and gypsum can enhance the leaching of excessive salt and reduce the Cr mobility. Among loamy soil, those with a higher CEC and organic matter content are more suitable for land disposal of drilling fluid.  相似文献   
110.
The dye-resist effect and leveling properties of hetero-mulifunctional dye-resist agents in acid dyeing of wool were investigated. The dye-resist agent with dichlorotriazinyl group achieved better resist effectiveness than those with monochlorotriazinyl group. The resist effectiveness was improved by increasing the number of sulfonate group in dye-resist agents. Also, the resist agents with more sulfonate groups showed better dye-assist effectivness, attributable to the increased electrostatic attraction between dye-resist agents and the cationic dye. However, the leveling properties of dye-resist agents decreased with the number of sulfonate groups in the molecule.  相似文献   
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