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991.
Cyrielle Finck Marc‐André D'Anjou Kate Alexander Swan Specchi Guy Beauchamp 《Veterinary radiology & ultrasound》2014,55(5):472-479
Mechanical obstruction is a frequent cause of acute vomiting in dogs requiring prompt diagnosis to improve patient management and prognosis. The purpose of this retrospective study was to compare small intestinal radiographic characteristics in dogs with versus without mechanical intestinal obstruction. Fifty dogs with gastrointestinal clinical signs and abdominal radiographs were recruited from hospital record archives and assigned to groups (group 1, obstructive, n = 25; group 2, nonobstructive n = 25). Abdominal radiographs were randomized and independently interpreted by three examiners who were unaware of group status. Intestinal dilation was subjectively scored based on distribution (segmental, regional or diffuse), and severity (absent, mild, moderate or severe). Small intestinal maximal diameter (SImax), L5 vertebral body height, small intestinal minimal diameter (SImin), and an estimated average of small intestinal diameters (SIave) were measured and three ratios were calculated: SImax/L5, SImax/SImin, and SImax/SIave. Segmental dilation was more prevalent in obstructed dogs for all examiners (P ≤ 0.03) and most nonobstructed dogs had no dilation (P ≤ 0.05). All ratios were higher in obstructed dogs (P < 0.002). Subjective dilation scores and ratio measurements had low interobserver agreement (absent to fair, with kappa values between ?0.06 and 0.57) and reproducibility (coefficients of 0.35–0.61). Findings indicated that dogs with SImax/L5 ≤ 1.4, SImax/SImin ≤ 2, and SImax/SIave ≤ 1.3 values are very unlikely to be mechanically obstructed; dogs with SImax/L5 ≥ 2.4, SImax/SImin ≥ 3.4 and SImax/SIave ≥ 1.9 are very likely obstructed, particularly if segmental dilation (less than 25% of the small intestine) is present. Dogs with ratios falling between these thresholds may need further testing unless other signs justify surgical exploration or endoscopy. 相似文献
992.
《Journal of Veterinary Behavior: Clinical Applications and Research》2014,9(6):341-346
Heart rate (HR) and heart rate variability (HRV) are often determined with Polar heart rate monitors (HRMs; S810i; Polar, Kempele, Finland). The aims of this study were to compare data from horses obtained by Polar HRMs and a portable Televet electrocardiogram (ECG; 100 version 4.2.3; Kruuse, Marslev, Denmark) device and to determine appropriate recording times in horses (n = 14). Correlations were calculated and a Bland-Altman analysis was carried out to examine agreement between recording systems. For beat-to-beat (RR) interval, uncorrected and corrected data were highly correlated irrespective of the recording system and recording time (r > 0.99, P < 0.001). For HRV variables, standard deviation of RR interval and root mean square of successive RR intervals, correlations higher than 0.9 were obtained between uncorrected and corrected ECG but not Polar data. The RR interval, HR, and HRV from corrected Televet and Polar data at no time differed between the recording systems. However, with the increase in recording time, the RR interval decreased (P < 0.001). Thus, for comparisons, recording intervals of similar length should be chosen. Correlations among RR interval, HR, and HRV variables obtained by ECG and HRMs were highly significant at all recording times (r > 0.9, P < 0.001). Correlations increased with increasing recording time. Bland-Altman graphs showed a strong agreement between HRMs and ECG and mean RR intervals, HR, and HRV variables were close to identical. In conclusion, Polar HRMs are as adequate as ECG recordings in horses. Owing to a low HR in stationary horses, recording times below 2 minutes will underestimate changes in HR and HRV. 相似文献
993.
建立由数据库、模型库及图形显示系统组成的二化螟种群时间动态预测模拟系统,此系统可进行全省区域内二化螟种群时间动态的模拟测报绘图和种群时间动态影响因子分析。系统模型的有效性检验和灵敏度分析表明,预测的各地一代发生期比较接近田间实际发生期,计算绘出的全省各地发育进度和发生代次能反映出各地理区域的基本发生趋势。地理海拔、早稻收割、耕作制度等都将影响种群的时间动态。 相似文献
994.
重庆合川市土壤侵蚀时空变化研究 总被引:1,自引:0,他引:1
利用遥感技术与地理信怎系统技术的结合,对重庆合川市的土壤侵蚀状况进行了时空变化研究。研究结果表明,合川市的土壤侵蚀状况在侵蚀面积和程度上都有不同程度的改善;土壤侵蚀具有时空差异大,侵蚀与水、热基本同期,侵蚀高峰超前于降水高峰的特点。 相似文献
995.
996.
流动沙漠地区灌溉林地盐结皮层特征的初步研究 总被引:4,自引:0,他引:4
盐结皮是干旱区灌溉后土壤表层形成的一个特殊层次,但目前对其形成条件和时空变化规律尚无系统研究.该文通过对2004和2005年在塔克拉玛干沙漠布置的试验地的调查研究表明,在咸水灌溉林地,土壤表层形成明显的盐结皮层.该文对盐结皮层厚度和电导率这两个主要特征进行了综合分析,得到以下结论:①灌溉水质、灌溉方式、灌水定额、灌水周期以及土壤质地在很大程度上可以影响盐结皮的性质.②盐结皮的性质具有明显的空间分布规律,畦灌和滴灌对林地盐结皮性质的微空间分布影响很大,坡向、土壤结构等立地条件在一定程度上也影响盐结皮性质的空间分布.③盐结皮性质存在明显的时间变化,在灌溉周期内,电导率经历增加→降低→稳定的变化过程,一般在灌溉后5 d盐结皮层开始形成;在年内盐结皮的电导率随着气温的变化而呈明显的月际变化;由于土壤中大气降尘和植物枯枝落叶年复一年的加入而导致土壤表层结构的极大变化,因此随着林地的发育,盐结皮层厚度逐渐趋于稳定,而电导率呈先增加后降低的趋势. 相似文献
997.
人工林油松木材管胞长度与纤丝角的变异性和相关性研究 总被引:2,自引:0,他引:2
张顺泰 《山东农业大学学报(自然科学版)》1988,(3)
本文主要介紹油松(Pinus tabulaeformis Carr)木材管胞长空与纤丝角的变异规律及其相关关系,提出了油松木材管胞长度与纤丝角的回归方程,并进行了显著性F值检验。 相似文献
998.
Australian Bat Lyssavirus (ABLV) is a fatal rabies‐like disease spread to humans from bats. All people who report bat bites or scratches in Queensland are considered potentially exposed to ABLV and are followed up and treated to prevent ABLV. Preventing members of the public intentionally interacting with bats will reduce the number of potential exposures to ABLV. In order to target public health messaging, this study examines the epidemiology of potential ABLV exposures in Metro North Hospital and Health Service (HHS), a region of Queensland that encompasses metro and rural areas in the south‐east of the state. People who intentionally handled bats during the study period were more likely to be adult (93%), male (60%), scratched (51%) by a megabat (72%) and been potentially exposed while rescuing the bat when it was trapped or injured (72%). The number of potential exposures reported in Queensland has increased since 2013; the same year, a Queensland child died of ABLV. Seasonally, exposures are more common during bat breeding and nursing periods when bats are more active (summer to autumn). Although there were more notifications in a band stretching north from the inner city to northern metro suburbs, notification rates were higher in large rural statistical areas in the north of the HHS. These data will be used to develop geographically targeted ABLV prevention messaging for the general public. 相似文献
999.
不同小麦品种组合条件下条锈病流行的时间动态 总被引:4,自引:0,他引:4
为了明确条锈病在小麦混合群体中的发展规律,采用人工接种方法研究了不同抗性小麦品种混播条件下条锈病的流行动态。结果表明,混播群体中条锈病的病情和流行速率降低;在2~4个抗性小麦品种组合中,其混合效应随混合群体中小麦品种组合数目的增多而增强,当组分数目增加到5个时,混合效应不再继续增加;在小麦品种搭配上,以抗感搭配效果显著。 相似文献
1000.
紫色土坡地尺度土壤养分的空间变异特性 总被引:2,自引:0,他引:2
利用地统计学方法,结合坡地土壤养分采样分析与G IS技术,分析紫色土坡地土壤养分空间变异特征。结果表明地块尺度上土壤养分的空间变异特性和空间相关性具有明显特征,其中土壤有机质、全氮和有效磷具有很强的空间异质性;碱解氮和pH具有中等的空间异质性;而速效钾不具有空间异质性。利用克里格法进行插值并绘制各养分属性的等值线图,表现出空间分布的类似性,但因微地形和耕作管理的影响而表现出各自的规律性,其中土壤有机质、全氮和有效磷的分布具有相似性,而碱解氮、速效钾和pH具有明显不同的分布规律。对典型地块的空间异质性分析有助于坡地和小流域尺度的土壤采样和调查分析,同时对地块水文过程分析和模型应用有重要参考价值。 相似文献