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排序方式: 共有598条查询结果,搜索用时 11 毫秒
141.
142.
Dong Woo Chang Bora Kim Jae Hoon Shin Young Min Yun Jung Ho Je Yeu kuang Hwu Jung Hee Yoon Je Kyung Seong 《Journal of veterinary science (Suw?n-si, Korea)》2011,12(2):107-113
The X-ray synchrotron is quite different from conventional radiation sources. This technique may expand the capabilities of conventional radiology and be applied in novel manners for special cases. To evaluate the usefulness of X-ray synchrotron radiation systems for real time observations, mouse fetal skeleton development was monitored with a high resolution X-ray synchrotron. A non-monochromatized X-ray synchrotron (white beam, 5C1 beamline) was employed to observe the skeleton of mice under anesthesia at embryonic day (E)12, E14, E15, and E18. At the same time, conventional radiography and mammography were used to compare with X-ray synchrotron. After synchrotron radiation, each mouse was sacrificed and stained with Alizarin red S and Alcian blue to observe bony structures. Synchrotron radiation enabled us to view the mouse fetal skeleton beginning at gestation. Synchrotron radiation systems facilitate real time observations of the fetal skeleton with greater accuracy and magnification compared to mammography and conventional radiography. Our results show that X-ray synchrotron systems can be used to observe the fine structures of internal organs at high magnification. 相似文献
143.
144.
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
145.
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
146.
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
147.
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
148.
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
149.
150.
Yang SJ Park KY Kim SH No KM Besser TE Yoo HS Kim SH Lee BK Park YH 《Veterinary microbiology》2002,86(4):295-301
Fourteen and 22 each of Salmonella Enteritidis and Salmonella Typhimurium (S. Typhimurium) were isolated from animals from 1983 to 1999 in Korea and tested for their antibiotic resistance patterns, phage types and resistance gene patterns. S. Typhimurium isolates were highly resistant to streptomycin, sulfisoxazole and tetracycline, 95, 95 and 86%, respectively. The incidence of multiple antibiotic resistance (resistant to more than two drugs tested) of S. Typhimurium isolates was extremely high (100%) comparing to S. Enteritidis isolates (21%). Two of the five ACSSuT (ampicillin, chloramphenicol, streptomycin, sulfisoxazole and tetracycline) resistant type S. Typhimurium isolates were phage type definitive type 104 (DT104).For the detection of resistance related genes in S. Enteritidis and S. Typhimurium isolates, particularly ACSSuT type S. Typhimurium, antibiotic resistance genes, cmlA/tetR, bla(PSE-1) and bla(TEM), and genus Salmonella specific gene, sipB/C, were amplified using four pairs of primers in a hot-start multiplex polymerase chain reaction (PCR). Two Korean isolates of S. Typhimurium DT104 showed bla(TEM) amplicons instead of bla(PSE-1) for the ampicillin resistance and they were susceptible to florfenicol. The multiplex PCR used in this study was useful in characterization of multiple drug resistant Salmonella isolates, especially ACSSuT type S. Typhimurium, and identification of beta-lactamase gene distribution among Salmonella isolates. 相似文献