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863.
864.
我国油菜籽及菜子油进口依赖性与进口安全研究 总被引:1,自引:1,他引:0
为判断我国油菜籽及菜子油进口来源的可靠性,降低进口风险,考察我国对主要来源国的进口依赖关系。在分析我国油菜籽和菜子油进口市场结构的基础上,综合考察我国油菜籽及菜子油从各主要来源国的进口占总进口值的份额(I1)、进口来源国对我国出口占该国总出口值的份额(I2),各主要出口国的油菜籽及菜子油出口值占世界的份额(P值)以及我国与各国总体贸易平衡状况(B指数),测算我国对主要进口来源市场的进口依赖系数(I3及I5),并评价进口安全性。结果表明我国油菜籽和菜子油进口主要依赖加拿大市场,但对加拿大的油菜籽进口依赖系数I3和I5分别从2005年的12.781 8和4.322 4下降到2012年的2.662 5和1.032 7,菜子油I3和I5分别从2005年的5.079 8和0.906 2下降到2012年的2.232 7和0.856 1。得出加拿大是我国油菜籽和菜子油进口的安全来源,进口油菜籽比菜子油更加经济合理的结论,并提出相关对策建议。 相似文献
865.
866.
Molecular detection and characterization of unclassified bovine enteric caliciviruses in South Korea 总被引:1,自引:0,他引:1
Park SI Jeong C Park SJ Kim HH Jeong YJ Hyun BH Chun YH Kang MI Cho KO 《Veterinary microbiology》2008,130(3-4):371-379
The unclassified bovine enteric calicivirus (BEC) is a new bovine enteric calicivirus that is different from bovine norovirus, and causes diarrhea and pathologies in the small intestine of calves. This virus includes Nebraska (NB)- and Newbury agent 1 (NA1)-like strains. The prevalence of this BEC and its genetic characterization has only been reported in the UK and the USA. This study examined the prevalence and genetic diversity of these BECs in diarrheic calves in South Korea. Among a total of 645 diarrheic fecal specimens obtained from 629 cattle herds, these unclassified BECs were detected in 59 (9.1%) diarrheic fecal samples from 57 herds (9.3%) by either RT-PCR or nested PCR. Sequence and phylogenetic analyses of the partial RdRp gene showed that all the Korean BECs clustered together and were closely related to the NB-like viruses (80.9-88.1% nucleotide and 84.5-98.4% amino acid) but not to the NA1-like viruses (75.8-78.4% nucleotide and 79.7-82.8% amino acid). Although these viruses could not be classified into NA1- and NB-like viruses from the sequence and phylogenetic data of the entire capsid gene, all the Korean BECs clustered together on a branch separate from the other known BECs. These results show that these BEC infections are endemic in diarrheic calves in South Korea. The infecting strains are genetically closer to the NB-like viruses but have a distinct evolutionary pathway. 相似文献
867.
Kang JH Yang MP 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2008,22(5):1166-1173
Background: The use of soybean oil-based lipid emulsion (SO-based LE) in parenteral nutrition has been reported to impair neutrophil functions in humans and rodents. As yet, little is understood about the effects of SO-based LE on canine immune responses.
Hypothesis: A short-term infusion with SO-based LE affects the phagocytic responses of canine peripheral blood polymorphonuclear neutrophilic leukocytes (PMNs).
Animals: Twenty-four healthy Beagle dogs.
Methods: Experimental study. Dogs were randomly assigned into groups of six and administered a 2-hour IV infusion with 0.9% NaCl solution or sufficient SO-based LE (INTRALIPOS 20%) to supply 40, 100, and 200% of the basal energy requirement (BER). PMN functions were determined after collecting blood samples before, immediately after, and 24 hours after the infusion.
Results: None of the treatments significantly affected the phagocytic capacity of PMNs or circulating leukocyte numbers. The infusion providing 200% of BERs significantly reduced PMN oxidative burst activity, filamentous actin polymerization, and Cdc42 Rho guanosine triphosphatase activity immediately after its delivery. However, these functions were restored to pre-infusion values 24 hours after the infusion. The lower calorie infusions did not have these effects.
Conclusions and Clinical Importance: These results suggest that short-term infusions with a supraphysiological dose of SO-based LE may decrease the immune functions of canine PMNs. However, more long-term studies will be needed to extrapolate the effect of SO-based LE with clinically relevant doses in a practical situation. 相似文献
Hypothesis: A short-term infusion with SO-based LE affects the phagocytic responses of canine peripheral blood polymorphonuclear neutrophilic leukocytes (PMNs).
Animals: Twenty-four healthy Beagle dogs.
Methods: Experimental study. Dogs were randomly assigned into groups of six and administered a 2-hour IV infusion with 0.9% NaCl solution or sufficient SO-based LE (INTRALIPOS 20%) to supply 40, 100, and 200% of the basal energy requirement (BER). PMN functions were determined after collecting blood samples before, immediately after, and 24 hours after the infusion.
Results: None of the treatments significantly affected the phagocytic capacity of PMNs or circulating leukocyte numbers. The infusion providing 200% of BERs significantly reduced PMN oxidative burst activity, filamentous actin polymerization, and Cdc42 Rho guanosine triphosphatase activity immediately after its delivery. However, these functions were restored to pre-infusion values 24 hours after the infusion. The lower calorie infusions did not have these effects.
Conclusions and Clinical Importance: These results suggest that short-term infusions with a supraphysiological dose of SO-based LE may decrease the immune functions of canine PMNs. However, more long-term studies will be needed to extrapolate the effect of SO-based LE with clinically relevant doses in a practical situation. 相似文献
868.
以8只装有永久性瘤胃瘘管的成年徐淮山羊为试验动物,采用自身对照设计,研究丙酮酸钙对山羊瘤胃内挥发性脂肪酸浓度动态变化的影响。结果表明:与对照组相比,添喂丙酮酸钙后,在0~8h内,对pH值无显著影响。4h时,总挥发性脂肪酸(TVFA)浓度升高25%(P<0.01);丙酸浓度升高60%(P<0.01)。0~8h内,丙酸比例均高于对照组(17%~30%);乙丙比均低于对照组(20%~29%)。说明在山羊日粮中添加一定量丙酮酸钙,可在不影响pH值的情况下,提高丙酸比例,降低乙丙比,改变瘤胃发酵类型。 相似文献
869.
OBJECTIVE: To examine whether in vitro treatment with trans-10, cis-12 conjugated linoleic acid (t10c12-CLA) restores the phagocytic capacity and oxidative burst activity (OBA) of canine polymorphonuclear neutrophilic leukocytes (PMNs) exposed to methylprednisolone sodium succinate (MPSS). SAMPLE POPULATION: Peripheral blood PMNs obtained from 12 healthy Beagles. PROCEDURES: The experimental design involved administration of a high dose of MPSS, which is the recommended protocol for dogs with acute spinal cord injury. To evaluate PMN function, blood samples were collected from dogs before IV injections of doses of MPSS or saline (0.9% NaCl) solution (time 0) and 2, 12, and 24 hours after injections ceased. Polymorphonuclear neutrophilic leukocytes were isolated from blood samples and incubated with t10c12-CLA alone or t10c12-CLA in combination with N-acetylcysteine (an antioxidant agent). Phagocytic capacity and OBA were measured simultaneously by use of flow cytometry. RESULTS: The phagocytic capacity and OBA of PMNs were suppressed by IV injection of MPSS and restored 12 hours after injection ceased. In vitro treatment with t10c12-CLA enhanced the phagocytic capacity and OBA of PMNs, regardless of whether dogs had been treated with MPSS. Effects of t10c12-CLA on OBA were detected only when phagocytosis was stimulated by microspheres. Use of N-acetylcysteine attenuated the stimulatory effects of t10c12-CLA. CONCLUSIONS AND CLINICAL RELEVANCE: Exposure to t10c12-CLA enhanced the phagocytic capacity and OBA of canine PMNs, and this effect may have involved t10c12-CLA-induced generation of reactive oxygen species. 相似文献
870.
禽源大肠埃希菌Biolog鉴定和系统发育分析 总被引:1,自引:0,他引:1
采用Biolog和16S rRNA基因序列分析法对中国兽医药品监察所菌种室收集保藏的18株大肠埃希菌(Escherichia coli)进行了鉴定.菌株经纯化培养,用Biolog微生物鉴定系统进行了鉴定,结果表明18株菌株为大肠埃希菌.提取基因组DNA,采用16S rRNA通用引物,用PCR进行16S rRNA基因序列扩增,扩增产物纯化后进行测序.序列经人工校对后用Clustal X 1.83软件进行比对分析,采用Mega 3.1软件构建系统发育树,结果表明18株菌株为大肠埃希菌. 相似文献