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61.
A visual analog scale and a numeric scoring scale were designed for the assessment of dynamic intraoperative mesenteric portovenography in the dog and cat. Two independent observers evaluated both scoring scales for reproducibility (differences between observers) and repeatability (within-observer differences) in the assessment of 60 trial portovenograms. Agreement (interchangeability) of both scales was evaluated by comparing the scores obtained in the assessment of 200 portovenograms obtained from 100 dogs and cats. There was no statistical difference between the two observers when scoring the same portovenogram for either the visual analog scale (p = .730, reproducibility coefficient = 17.85 units) or the numeric scoring scale (scores identical, reproducibility coefficient = 0). There was no statistical difference, for either of the observers, when the same portovenogram was assessed on two separate occasions using the visual analog scale (observer 1, p = .35, repeatability coefficient = 17.93 units; observer 2, p = .42, repeatability coefficient = 8.27 units) or the numeric scoring scale (scores given by both observers were identical, repeatability coefficient = 0 for both observers). The results of comparison between the visual analog scale and numeric scoring scale confirmed that the two scoring systems were not directly interchangeable. Although both scoring systems demonstrated good reproducibility and repeatability, the numeric scoring scale possessed a number of inherent deficiencies that suggested it was not the method of choice for the assessment of the subjective data obtained from dynamic intraoperative mesenteric portovenography.  相似文献   
62.
REASON FOR PERFORMING STUDY: Epiploic foramen entrapment (EFE) is one of the most common causes of small intestinal strangulation in the horse. Identification of risk factors would generate hypotheses about causation and may suggest preventive strategies. HYPOTHESIS: Horses exhibiting certain behavioural patterns and those exposed to particular management practices are at increased risk of EFE. METHODS: A matched case-control study was conducted on EFE cases admitted to hospitals in the UK, Ireland and USA. Data on 109 cases and 310 control horses were obtained by telephone questionnaire and conditional logistic regression was used to identify associations between horse- and management-level variables and the risk of EFE. RESULTS: Crib-biting/windsucking behaviour was strongly associated with increased risk of EFE (OR 67.3, 95%CI 15.3-296.5). A history of colic in the previous 12 months (OR 4.4, 95%CI 1.5-12.7) and horses of greater height (OR/cm 1.05, 95%CI 1.01-1.08) were also at increased risk. The person(s) responsible for horses' daily care (nonowner/relative/spouse OR 5.5, 95%CI 2.3-13.3) and a number of behavioural features, including response to a stimulus causing fright (easily frightened OR 0.4, 95%CI 0.1-1.0) or excitement (sweats up easily/occasionally OR 0.3, 95%CI 0.1-0.8), reaction to their surroundings (inquisitive OR 0.4, 95%CI 0.2-0.8) and feeding behaviour when stressed (goes off food in full/part OR 0.3, 95%CI 0.1-1.0) were also associated with altered risk of EFE. CONCLUSIONS: The association between horses of greater height and those with a previous history of colic and increased risk of EFE suggests that some horses may be inherently predisposed to EFE. Furthermore, a behavioural pattern has been characterised that is common to horses at increased risk of EFE. Further research is required to investigate the causal pathway linking behavioural traits with gastrointestinal dysfunction and to determine whether behavioural modification reduces the risk of EFE. POTENTIAL RELEVANCE: The findings of the present study have relevance to horses in the UK, Ireland and USA.  相似文献   
63.
研究了广西右江河谷地区芒果中农药残留现状,并做了人群的膳食风险评估,旨在为芒果农产品的农业主管部门监管提供科学依据。在右江河谷产区采集99份芒果样品,对样品中107种农药残留进行分析检测,并运用点评估方法对农药残留膳食摄入风险进行评估。结果表明,芒果的检出农药类型上,以甲氧基丙烯酸酯类杀菌剂为主,检出率高达61.61%;累计检出20种农药残留,样品检出率为80.80%,其中吡唑醚菌酯检出率最高,达到46.46%;按照GB 2763-2021判定,超标数量达到14份,占总样品数量的14.14%,吡唑醚菌酯和氯氟氰菊酯两种农药超标;检出农药对成人和儿童的慢性膳食摄入%ADI在0.00 -2.43 %之间,其中氯氟氰菊酯、联苯菊酯对儿童的急性膳食摄入%ARfD分别为101.82%、136.16 %,所有检出农药对成人的急性膳食摄入%ARfD均小于100 %。广西右江河谷地区芒果中多农药组分残留情况明显,吡唑醚菌酯和氯氟氰菊酯需要重点监测关注;儿童对芒果中摄入氯氟氰菊酯和联苯菊酯的农药残留急性膳食有一定的暴露风险,成人对芒果中检出的所有农药急、慢性膳食暴露风险极低。  相似文献   
64.
本研究通过对东祁连山不同土地利用类型下土壤的7种重金属含量进行测定,结合青藏高原土壤元素背景值,对土壤重金属污染程度和综合潜在生态风险做出综合性评价。结果表明:7种重金属元素的均值都超过了土壤元素背景值,其中Zn和Ni平均含量较高,为196.67 mg·kg-1和74.28 mg·kg-1,分别是土壤背景值的3.20和3.00倍,形成了土壤重金属元素的富集现象;内梅罗综合污染指数法和潜在生态风险系数法分析显示,各类型土地平均内梅罗综合污染指数为2.84,属于中度污染程度,其中农田平均污染指数最大,为3.10,达到了重度污染水平;草地为2.71,湿地最小为2.49,均为中度污染水平。各类型土地的综合潜在生态风险系数为94.31,其中农田类风险系数最高,为101.90,草地类为92.22,湿地为73.29;各类型土壤中Zn元素变异系数最低;Cd元素变异系数最高。  相似文献   
65.
Developing country livestock production systems are diverse and dynamic, and include those where existing indigenous breeds are currently optimal and likely to remain so, those where non‐indigenous breed types are already in common use, and systems that are changing, such as by intensification, where the introduction of new breed types represents significant opportunities. These include opportunities to improve the livelihood of the world's poor, increase food and nutrition security and enhance environmental sustainability. At present, very little research has focused on this issue, such that significant knowledge gaps in relation to breed‐change interventions remain. The purpose of this study is to raise awareness of this issue and suggests strategic research areas to begin filling these knowledge gaps. Such strategic research would include (i) assessing the impact of differing breed types in developing country livestock productions systems, from a range of viewpoints including intrahousehold livelihood benefit, food and nutrition security at different scales, and environmental sustainability; (ii) identification of specific livestock production systems within developing countries, and the type of livestock keepers within these system, that are most likely to benefit from new breed types; and (iii) identification of new breed types as candidates for in‐situ testing within these systems, such as through the use of spatial analysis to identify similar production environments combined with community acceptance studies. Results of these studies would primarily assist stakeholders in agriculture, including both policy makers and livestock keepers, to make informed decisions on the potential use of new breed types.  相似文献   
66.
以茎直黄芪人工饲喂2月龄实验家兔中毒,设置对照组、攻毒组、攻毒解毒治疗组,每组实验家兔4只,建立中毒及解毒病理模型,在28d、45d(中毒死亡)、49d(解毒组及空白组处死),研究实验家兔体内的病理变化规律,并对速康解毒口服液治疗效果进行评估。实验结果表明,攻毒组、攻毒解毒解毒组实验家兔在18d左右出现中毒症状,攻毒组Ⅱ号在28d中毒死亡,在第29d时对解毒组利用速康口服液解毒治疗均成活。病理学切片观察表明,攻毒组试验家兔表现为大部分脏器均出现淤血、炎症、坏死等病理变化,解毒治疗组出现轻度淤血、轻度的细胞变性。研究表明速康解毒口服液能有效提高α-甘露糖甙酶活性,解毒组试验家兔病理组织学观察结果表现轻微,证实速康解毒口服液具有较好的解毒效果。  相似文献   
67.
AIMS: To determine the frequency with which porcine reproductive and respiratory syndrome (PRRS) virus (PRRSv) would become established in a non-commercial pig herd in New Zealand due to illegal feeding of uncooked food waste containing virus-contaminated pigmeat. To determine the likelihood of a single incursion resulting in a multi-farm outbreak of the disease, and describe the spatio-temporal characteristics of such an outbreak.

METHODS: A Monte Carlo simulation model was constructed to determine the expected annual frequency of PRRSv infection being initiated in a non-commercial pig herd as a result of inadvertent feeding of pigmeat imported from countries endemically infected with the disease. Once the likelihood of PRRSv becoming established in a single pig herd was determined, stochastic spatially explicit infectious disease modelling software was utilised to model the temporal and spatial characteristics of the resulting epidemic.

RESULTS: Assuming the proportion of imported pigmeat remained at current levels, consumption patterns of pigmeat in households in New Zealand remained steady, and limited compliance with recently reintroduced regulations to prevent feeding of uncooked food waste, at least 4.3 pig herds per year were predicted to become infected with PRRSv. Simulation modelling of PRRSv epidemics related to initial infection of a non-commercial farm produced an estimate that 36% of these incursions would spread from the initial herd, and that these outbreaks would involve 93 herds on average in the first year. By increasing the estimated persistence of PRRSv infection in small herds, an average of 205 herds became infected in the first year.

CONCLUSIONS: Given a mean of 4.3 infected premises per year and a 36% probability of infection spreading beyond the initial infected herd, there was a 95% likelihood of a multi-farm PRRS outbreak occurring within 3 years.

CLINICAL RELEVANCE: Introduction of PRRSv through importation of virus-contaminated pigmeat presents a high risk for establishment of the disease in the pig industry in New Zealand.  相似文献   
68.
李妙娟 《中国饲料》2021,1(7):135-138
面对日益复杂的竞争形势,饲料加工企业需要加强内控管理.为了评价内控体系的有效性,通常寻找一些评价指标形成体系对内控进行评价.本文提出构建内控评价指标体系需要一些前提,包括对关键环节的识别、评价原则的确定等,在指标选取中,至少应涵盖公司层面、业务层面、财务层面和合法合规层面的指标.内控评价体系构建后,需要有组织保障和制度...  相似文献   
69.
本文阐述了与兽用基因工程生物制品的生物安全性评价有关的动物病原体的危害性分类与生物安全等级、安全性评价的内容和要求及制品的安全性复核检验等内容  相似文献   
70.
石门国家森林公园风景资源质量等级评定   总被引:1,自引:0,他引:1       下载免费PDF全文
文章是在对广东省石门国家森林公园风景资源进行全面系统普查的基础上,依据《中国森林公园风景资源质量等级评定》(GB/T 18005-1999)标准,从风景资源质量评价、区域生态状况评价和旅游开发利用条件评价等三个方面对石门国家森林公园进行等级评定,结果表明石门国家森林公园风景质量达到一级,风景资源的资源价值和旅游价值高,评定结果可为公园的保护性开发提供科学依据和理论指导。    相似文献   
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