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131.
Yucheol Jeong Changyun Lim Sunkyoung Oh Joohyun Jung Jinhwa Chang Junghee Yoon Mincheol Choi 《Journal of veterinary science (Suw?n-si, Korea)》2008,9(4):407-413
Eight Beagle dogs were anesthetized and were imaged using a single channel helical CT scanner. The contrast medium used in this study was iohexol (300 mg I/ml) and doses were 0.5 ml/kg for a cine scan, 3 ml/kg for an enhanced scan. The flow rate for contrast material administration was 2 ml/sec for all scans. This study was divided into three steps, with unenhanced, cine and enhanced scans. The enhanced scan was subdivided into the arterial phase and the venous phase. All of the enhanced scans were reconstructed in 1 mm intervals and the scans were interpreted by the use of reformatted images, a cross sectional histogram, maximum intensity projection and shaded surface display. For the cine scans, optimal times were a 9-sec delay time post IV injection in the arterial phase, and an 18-sec delay time post IV injection in the venous phase. A nine-sec delay time was acceptable for the imaging of the canine hepatic arteries by CT angiography. After completion of arterial phase scanning, venous structures of the liver were well visualized as seen on the venous phase. 相似文献
132.
Enterohemorrhagic Escherichia coli serotype O157:H7 is a pathotype of diarrheagenic E. coli that produces one or more Shiga toxins, forms a characteristic histopathology described as attaching and effacing lesions, and possesses the large virulence plasmid pO157. The bacterium is recognized worldwide, especially in developed countries, as an emerging food-borne bacterial pathogen, which causes disease in humans and in some animals. Healthy cattle are the principal and natural reservoir of E. coli O157:H7, and most disease outbreaks are, therefore, due to consumption of fecally contaminated bovine foods or dairy products. In this review, we provide a general overview of E. coli O157:H7 infection, especially focusing on the bacterial characteristics rather than on the host responses during infection. 相似文献
133.
Dayoung Oh Siheon Lee Seungji Kim Sangkyung Choen Mincheol Choi Junghee Yoon 《Veterinary radiology & ultrasound》2019,60(1):28-37
Bronchomalacia and bronchial collapse are important causes of chronic coughing in dogs. The current reference standard diagnostic tests for these problems are flexible bronchoscopy and biopsy. Previous human studies have also supported inspiration/expiration computed tomography (CT) as a diagnostic test. The current prospective, pilot study aimed to determine whether inspiration/expiration CT is also a feasible test for quantifying bronchial collapsibility in dogs. Thoracic CT images were acquired using a 64‐row multidetector CT for 10 healthy Beagle dogs during maximal inspiration and expiration. For each scan, one observer measured transverse sectional areas of the mainstem and lobar bronchi, and the dorsal and ventral segmental bronchi of the left cranial lobar bronchus. Diameters for each bronchus were also measured in transverse, sagittal, and dorsal planes. Bronchial collapsibility (%) was calculated as the difference between inspiration/expiration transverse sectional areas divided by the inspiration transverse sectional areas. Mean bronchial collapsibility of all bronchi was 38.20 ± 15.17%. A collapsibility of over 50% was found in the dorsal (n = 7) and ventral (n = 4) segmental bronchi of the left cranial lobar bronchus, and the left caudal (n = 5) and right middle (n = 2) lobar bronchus. Bronchial collapsibility measurements were greater in the dorsal and ventral segmental bronchi of the left cranial lobar bronchus and the left caudal lobar bronchus (P < 0.001). Findings supported inspiration/expiration CT as a modality to noninvasively assess bronchial collapse in dogs and a bronchial collapsibility value greater than 50% for detecting pathologic bronchial collapse in clinically affected dogs. 相似文献
134.
135.
Murakami Hiroaki Yoon Seokjin Kasai Akihide Minamoto Toshifumi Yamamoto Satoshi Sakata Masayuki K. Horiuchi Tomoya Sawada Hideki Kondoh Michio Yamashita Yoh Masuda Reiji 《Fisheries Science》2019,85(6):1109-1109
Fisheries Science - In the original publication the text in right column of page 330, the sequences of primers were incorrectly published as. 相似文献
136.
S. H. Lee A. Hosseindoust S. Laxman Ingale P. C. Rathi S. Y. Yoon J. W. Choi 《British poultry science》2020,61(1):57-62
ABSTRACT1. The aim of this trial was to determine the optimal supplementation level of a xylanase enzyme from Trichoderma citrinoviride on growth performance, apparent ileal and total tract nutrient retention, intestinal morphology, and intestinal concentration of volatile fatty acids in broiler chickens.2. A total of 600 broiler chickens (Ross 308) of mixed sex were randomly allotted to four treatments, on the basis of similar body weight. The dietary treatments were made from a corn-wheat-soy based diet supplemented with either 0, 3750, 7500, or 11 250 XU/kg xylanase and were fed to 32 d of age.3. A linear response to increasing dietary xylanase was demonstrated for overall weight gain (P < 0.05) and feed conversion ratio (P < 0.05). The apparent total tract digestibility of dry matter and gross energy, and the coefficient of apparent ileal digestibility (CIAD) of N and soluble non-starch polysaccharides were linearly improved when xylanase was added to the diet (P < 0.05). Moreover, a linear increase (P < 0.05) was observed in the CIAD of Arg, Lys, and Try with increasing dietary levels of xylanase.4. The viscosity of digesta in ileum was linearly decreased when dietary xylanase level increased (P < 0.05).5. An increase in villus height of the duodenum and jejunum were observed with increasing dietary levels of xylanase (linear, P < 0.05).6. Overall, the results showed that the effects of dietary xylanase supplementation on broiler performance was determined through effects on nutrient availability and intestinal morphology. 相似文献
137.
Conifer needles exposed to ambient air pollutants were observed by a scanning electron microscope (SEM). Predominant changes on needles were the breakdown and the aggregation of wax structures on stomatal chambers. However, the mode of destruction in stomatal wax structures was dependent on the pollutants. Ginkgo biloba seemed to be resistant to air pollutants despite higher amounts of sulfur in the foliage. 相似文献
138.
Molecular characterization of recent Korean porcine reproductive and respiratory syndrome (PRRS) viruses and comparison to other Asian PRRS viruses 总被引:14,自引:0,他引:14
Cha SH Choi EJ Park JH Yoon SR Song JY Kwon JH Song HJ Yoon KJ 《Veterinary microbiology》2006,117(2-4):248-257
Twenty-eight PRRS viruses (PRRSVs) isolated from various pig farms in Korea between 2002 and 2003 were sequenced for open-reading frame (ORF) 5 and/or full-length genome and compared with numerous PRRSVs reported from North America, Europe and Asia. All Korean isolates examined were genetically of the North American genotype. The ORF5 sequence of one isolate was identical to Ingelvac PRRS MLV vaccine virus. ORF5 nucleotide sequence divergence of the remaining 27 Korean PRRSVs from VR-2332, the prototype of the North American PRRSV and parental strain of the MLV vaccine virus, ranged from 1.3% to 12.9%, which corresponded to 2.0% to 14.9% divergence at the amino acid level, raising a concern on the efficacy of the MLV vaccine. Phylogenetic analyses of ORF5 and/or full-length sequences revealed that the Korean PRRSVs formed a clade distinct from PRRSVs reported from other Asian countries (China, Taiwan, Japan, and Thailand). Our study demonstrated that PRRSVs of the North American genotype were introduced to the Korean swine population some time ago and have evolved independently from PRRSV in other Asian countries, suggesting that geographic separation might influence the molecular evolution of PRRSV. This should be taken into consideration when a national PRRS prevention and control policy for international trade is established. 相似文献
139.
Yeh JY Kim TJ Park SY Song CS Yoon YD Kim SK Lee JB Choi IS 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2006,68(5):499-501
Lawsonia intracellularis (L. intracellularis) was isolated from a Korean pig suffering acute proliferative enteropathy. In vitro culture conditions of L. intracellularis were established in McCoy cells. Pigs and hamsters experimentally infected with the pure culture of L. intracellularis reproduced clinical signs and intestinal lesions of proliferative enteropathy. The presence of L. intracellularis in the intestinal lesions was confirmed by immunohistochemistry with L. intracellularis-specific monoclonal antibodies. 相似文献
140.
Luo G Malkova S Yoon J Schultz DG Lin B Meron M Benjamin I Vanysek P Schlossman ML 《Science (New York, N.Y.)》2006,311(5758):216-218
Mean field theories of ion distributions, such as the Gouy-Chapman theory that describes the distribution near a charged planar surface, ignore the molecular-scale structure in the liquid solution. The predictions of the Gouy-Chapman theory vary substantially from our x-ray reflectivity measurements of the interface between two electrolyte solutions. Molecular dynamics simulations, which include the liquid structure, were used to calculate the potential of mean force on a single ion. We used this potential of mean force in a generalized Poisson-Boltzmann equation to predict the full ion distributions. These distributions agree with our measurements without any adjustable parameters. 相似文献