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51.
Stomach tissues from 222 beagle dogs, which were used for toxicological studies, were examined histopathologically. Out of 190 dogs fed the same diet, 185 had gastric lesions, whereas all of 32 dogs fed another diet were free from them. The gastric lesions were noted as an accumulation of eosinophils, infiltration of inflammatory cells including lymphocytes, plasma cells and histiocytes in the gastric lamina propria, formation of foreign body type multinucleated giant cells, focal desquamation and papillary proliferation of mucosal epithelium. The lesions were confined to the superficial layer of the antral and pyloric mucosa, and neither desmoplasia nor clinical signs were seen. Multinucleated giant cells often contained amphophilic foreign bodies of varying appearance with inconsistent reaction for periodic acid-Schiff (PAS), but no definite causal agents were detected.  相似文献   
52.
我们用辣椒(Capsicum annuum)栽培种(已导入了灯笼椒Capsicum chinense L^3 基因)的种内F2代群体(2016株)和种间F2代群体(3391株)(由灯笼椒与Capsicum frutescence杂交产生)对灯笼椒抗烟草花叶病毒属病毒的L^3基因进行定位。通过L^3基因抗性紧密相关的AFLP分子标记的BAC文库的分析,揭示出番茄抗病同源基因12的存在。通过简并PCR技术,对来自35株不同辣椒的同源基因12的部分或全部编码序列进行克隆,且在种间组合中产生了17个遗传标记。图谱显示:L^3基因位于12同源基因标记IH1—04和BAC—end标记189D23M中间,L^3基因定位于包含两个不同BAC重叠群的区内,这两个不同的BAC重叠群分别由4个和1个无性系组成。DNA纤维荧光原位杂交揭示这两个重叠群被约30kb隔开。DNA纤维荧光原位杂交结果和BAC无性系的Southern杂交表明在高度重复序列中富集包含L^3基因位点的区。Southern杂交表明两个BAC重叠群包含多于十个的12同源基因拷贝体。相反,对于种间F2代群体,,重组后代没有结合位点,在种内F2代群体中,该结合位点存在于两个不同的BAC重叠群内,这两个不同的BAC重叠群分别由7个和2个无性系组成。而且,两个群体间结合位点分配的不同表明在含有L基因位点的区域连锁不平衡。  相似文献   
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In this study, we examined the locational effect (left or right ovary) of the preovulatory follicle (PF) on fertility in dairy heifers. In total, 1,111 artificial inseminations (AI) were analyzed. At AI, PF locations were examined using rectal palpation, and heifers were divided into two groups on their PF locations: (i) the PF located in the left ovary (L‐PF); and (ii) the PF located in the right ovary (R‐PF). Pregnancy was diagnosed by rectal palpation 60 days after AI. The conception rate was 50.7% in all heifers. Conception rate was significantly higher in the L‐PF (60.1%) than in the R‐PF (46.2%). The conception rate was significantly lower by sexed semen (48.6%) than conventional semen (59.1%). Conception rates divided by the semen type (sexed: n = 896, conventional: n = 215) were significantly higher in the L‐PF than in the R‐PF for both semen types (sexed; L‐PF vs. R‐PF: 57.3% vs. 44.4%, conventional; L‐PF vs. R‐PF: 72.3% vs. 53.3%). In addition, season, age, AI number, and the number of re‐inseminations at the same estrus did not affect conception rates. In summary, PF development in the left ovary was associated with increased conception rates in dairy heifers.  相似文献   
56.
Large-scale microwave rapid pyrolysis of cellulosic materials has been investigated. Levoglucosan (1,6-anhydro--d-glucopyranose) was obtained from a larch log as the main anhydrosugar in 2.6% yield on the basis of dry wood weight. This yield would be much higher than that obtainable by conventional pyrolysis in the largescale reaction. Levoglucosenone (1,6-anhydro-3,4-dideoxy--D-glycero-hex-3-enopyranos-2-ulose) was found to be produced in one-quarter the amount of levoglucosan. Other anhydrosugars, such as mannosan (1,6-anhydro--D-mannopyranose), galactosan (1,6-anhydro--d-galactopyranose), and xylosan (1,4-anhydro--d-xylopyranose), were also confirmed to be produced as minor components depending on the proportion of the monosaccharide content in the larch. When microwave pyrolysis of used papers and filter papers was performed, the yields of levoglucosan were about 6% and 12%, respectively, suggesting that a higher content of cellulose gives a larger amount of levoglucosan.  相似文献   
57.
We have established four monoclonal antibodies (MAbs) against the nucleocapsid protein (NP) of canine distemper virus (CDV). A competitive binding assay has revealed that the MAbs are directed against two antigenic domains. An immunofluorescence assay using a series of deletion clones of the NP and an immunoprecipitation assay using the NP have revealed that two of the MAbs recognize the C-terminal region of the NP while the other two recognize the tertiary structure of the N-terminal domain. These MAbs reacted with all eight strains of CDV used in this study, but showed different reactivities against measles virus and rinderpest virus.  相似文献   
58.
Eight types of microcapsules of European pear (La France) aroma model mixture were prepared, and their retained aroma components and sample microstructures (both surface and cross-section) were compared. The La France pear aroma model mixture was prepared by the mixing of hexanal and five kinds of esters. alpha-Cyclodextrin (alpha-CD), gum arabic (GA), soybean soluble polysaccharide (SSPS), and highly branched cyclic dextrin (HBCD) were used as carrier solids, and spray drying and freeze drying comprised the drying methods. The mean particle size of the microcapsules ranged from 8.34 microm for the microcapsules with alpha-CD to 9.67 microm for those with SSPS. The total aroma contents were different depending upon the microencapsulation systems (1.35 g/100 g of microcapsules for the spray-dried microcapsules with HBCD to 14.1 g/100 g of microcapsules for the freeze-dried microcapsules with GA). The microcapsules with alpha-CD and GA were stable against heat treatment (40, 80, or 120 degrees C for 60 min) under nitrogen gas flow.  相似文献   
59.
Porcine embryonic fibroblasts (PEFs) are widely used as donor cells for somatic cell nuclear transfer (SCNT) in pigs. Transfection of PEFs with exogenous DNA is essential for producing genetically modified (GM; transgenic or knockout) pigs via SCNT. In this case, selectable markers are strictly required selecting and enriching stably transfected cells. The most frequently used selective drug for this purpose is a neomycin analogue (G418/geneticin); neo has been widely used as a selectable marker gene in the genomic manipulation of pigs. However, little is known about optimal concentrations of other selection drugs. This often hampers functional analysis of the porcine genome and development of individual GM pigs. This study explores the optimal concentrations of selective drugs, other than neomycin, that can be used for the selection of transfected PEFs. Porcine embryonic fibroblasts were incubated in media containing different concentrations of drugs for up to 10 days, to determine the optimal drug concentrations fatal for PEFs. The following concentrations were found to be optimal selective concentrations for use with PEFs: G418/geneticin, 400 μg/ml; blasticidin S, 8 μg/ml; hygromycin B, 40 μg/ml; puromycin, 2 μg/ml; and zeocin, 800 μg/ml. Repeated transfections with plasmids carrying selectable markers resulted in the generation of multidrug-resistant swine transfectants. Furthermore, these markers were found to be independent. The present information will be useful for the production of SCNT-mediated GM piglets that express multiple transgenes.  相似文献   
60.
In this study, we demonstrated growth curves and reference values for hematological and serum biochemical parameters of Microminipigs, the world smallest experimental minipigs. In both male and female animals, the body weights (BWs) at 3 and 6 months of age were <5 kg and <10 kg, respectively, and growth curve revealed almost plateau (approximately 20 kg BW) after 18 months of age. Major hematological and serum biochemical parameters showed no gender differences and the values were very similar to those in G?ttingen and Yukatan minipigs. The values obtained in this study can serve as fundamental reference, and thereby facilitate the use of Microminipig in life science research.  相似文献   
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