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吸收剂量、贮藏时间及贮藏温度对辐照牛肉中2-十二烷基环丁酮的影响 总被引:1,自引:1,他引:1
分析了辐照牛肉中辐解产物2-十二烷基环丁酮在不同的吸收剂量(0.5~10.0kGy)、贮藏时间(0-40d)及贮藏温度(-20℃~4℃)下的变化规律。采用硅胶层析柱-气相色谱/质谱联用技术萃取分离并检测。结果表明,2-十二烷基环丁酮的浓度与吸收剂量呈线性正相关,随着贮藏时间延长其含量减少,贮藏温度对其没有显著影响。利用2-十二烷基环丁酮可鉴定牛肉是否经过辐照,在已知贮藏温度和时间的条件下,可评估辐照牛肉的大约吸收剂量范围。 相似文献
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在玛可河林业局育苗基地油松容器苗的培育过程中,发现有枯梢症发生,通过分析发生的主要原因,对油松枯梢症采取了预防措施,取得了明显效果. 相似文献
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Disease of geese caused by a new herpesvirus 总被引:3,自引:0,他引:3
PJ KETTERER BJ RODWELL HA WESTBURY† PT HOOPER† AR MACKENZIE‡ JG DINGLE§ HC PRIOR 《Australian veterinary journal》1990,67(12):446-448
A goose flock farmed outdoors in south-eastern Queensland suffered an outbreak of peracute disease with high death rate (97%). Small button ulcers and large plaques overlying lymphocyte aggregates were present on the mucosa of the small intestine of affected birds. Small white foci of necrosis and focal haemorrhages were seen in the livers. Numerous intranuclear inclusion bodies were observed microscopically in hepatocytes and a herpesvirus which grew rapidly in chicken kidney cells was isolated from tissues. Duck virus enteritis (DVE) was suspected but DVE antiserums failed to neutralise the virus. Further serological studies with a limited range of known avian herpesviruses have failed to identify the virus. Experimental transmission resulted in high mortality in geese (100%), lower mortality in ducklings and nil mortality in chickens. Surveillance studies showed no evidence of infection in domestic and wild birds beyond the original farm and the infection appears not to have been established in the area. Wild ducks, which were frequent visitors to the farm dam, were considered the most likely source of the infection. 相似文献
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Sarah Boveri Jacqueline C Brearley Alexandra HA Dugdale 《Veterinary anaesthesia and analgesia》2013,40(5):449-454
ObjectiveTo determine if body condition score (BCS) influences the sedative effect of intramuscular (IM) premedication or the dose of intravenous (IV) propofol required to achieve endotracheal intubation in dogs.Study designProspective clinical study.AnimalsForty–six client–owned dogs undergoing general anaesthesia.MethodsDogs were allocated to groups according to their BCS (BCS, 1 [emaciated] to 9 [obese]): Normal–weight Group (NG, n = 25) if BCS 4–5 or Over–weight Group (OG, n = 21) if BCS over 6. Dogs were scored for sedation prior to IM injection of medetomidine (5 μg kg?1) and butorphanol (0.2 mg kg?1) and twenty minutes later anaesthesia was induced by a slow infusion of propofol at 1.5 mg kg?1 minute?1 until endotracheal intubation could be achieved. The total dose of propofol administered was recorded. Data were tested for normality then analyzed using Student t–tests, Mann–Whitney U tests, chi–square tests or linear regression as appropriate.ResultsMean ( ± SD) propofol requirement in NG was 2.24 ± 0.53 mg kg?1 and in OG was 1.83 ± 0.36 mg kg?1. The difference between the groups was statistically significant (p = 0.005). The degree of sedation was not different between the groups (p = 0.7). Post–induction apnoea occurred in 11 of 25 animals in the NG and three of 21 in OG (p = 0.052).ConclusionsOverweight dogs required a lower IV propofol dose per kg of total body mass to allow tracheal intubation than did normal body condition score animals suggesting that IV anaesthetic doses should be calculated according to lean body mass. The lower dose per kg of total body mass may have resulted in less post–induction apnoea in overweight/obese dogs. The effect of IM premedication was not significantly affected by the BCS.Clinical relevanceInduction of general anaesthesia with propofol in overweight dogs may be expected at lower doses than normal–weight animals. 相似文献
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对内蒙古阿拉善左旗红砂荒漠土壤盐分离子含量和土壤含水量的分布规律进行了研究,并对两者之间做了相关和回归分析。结果表明,阿拉善左旗红砂荒漠土壤中盐分离子的含量,阳离子以Na+为主,阴离子以SO42-为主。在垂直分布上,Mg2+、Na+、Cl-和SO42-含量随着土层深度的增加而增加,而K+、CO32-和HCO3-含量随着土层深度的增加而减少。阿拉善左旗3个地区(乌力吉、长流水和孪井滩)的土壤含水量介于1.39%~8.01%之间,平均含水量为5.02%。3个地区中,红砂荒漠土壤所含盐分离子中的Mg2+、Cl-和SO42-均与其土壤含水量之间存在明显的线性关系。 相似文献