A comparison in dogs of medetomidine,with or without MK‐467, and the combination acepromazine‐butorphanol as premedication prior to anaesthesia induced by propofol and maintained with isoflurane

ObjectiveTo compare the haemodynamic effects of three premedicant regimens during propofol-induced isoflurane anaesthesia.Study designProspective, randomized cross-over study.AnimalsEight healthy purpose-bred beagles aged 4 years and weighing mean 13.6 ± SD 1.9 kg.MethodsThe dogs were instrumented whilst under isoflurane anaesthesia prior to each experiment, then allowed to recover for 60 minutes. Each dog was treated with three different premedications given intravenously (IV): medetomidine 10 μg kg^?1 (MED), medetomidine 10 μg kg^?1 with MK-467 250 μg kg^?1 (MMK), or acepromazine 0.01 mg kg^?1 with butorphanol 0.3 mg kg^?1 (AB). Anaesthesia was induced 20 minutes later with propofol and maintained with isoflurane in oxygen for 60 minutes. Heart rate (HR), cardiac output, arterial blood pressures (ABP), central venous pressure (CVP), respiratory rate, inspired oxygen fraction, rectal temperature (RT) and bispectral index (BIS) were measured and arterial and venous blood gases analyzed. Cardiac index (CI), systemic vascular resistance index (SVRI), oxygen delivery index (DO₂I), systemic oxygen consumption index (VO₂I) and oxygen extraction (EO₂) were calculated. Times to extubation, righting, sternal recumbency and walking were recorded. The differences between treatment groups were evaluated with repeated measures analysis of covariance.ResultsHR, CI, DO₂I and BIS were significantly lower with MED than with MMK. ABP, CVP, SVRI, EO₂, RT and arterial lactate were significantly higher with MED than with MMK and AB. HR and ABP were significantly higher with MMK than with AB. However, CVP, CI, SVRI, DO₂I, VO₂I, EO₂, T, BIS and blood lactate did not differ significantly between MMK and AB. The times to extubation, righting, sternal recumbency and walking were significantly shorter with MMK than with MED and AB.Conclusions and clinical relevanceMK-467 attenuates certain cardiovascular effects of medetomidine in dogs anaesthetized with isoflurane. The cardiovascular effects of MMK are very similar to those of AB.     

一种φ630直埋管抗压强度与轴向滑动试验装置

针对现有直埋夹套管总体抗压强度与轴向滑动试验装置普遍采用手动装卸砂、手动加载的特点,给出了规格为西630直埋夹套管总体抗压强度与轴向滑动试验装置的设计方案与工作原理,其主要由砂箱、液压加载装置、推拉力试验机、升降加砂装置、送管装置5个部分组成。砂箱底部设有出砂口,试验结束后,打开砂箱底部挡板,可将细砂弓I入其侧下方升降装置的储砂箱中,升降加砂装置可将储砂箱运到砂箱侧上方供再次试验时使用,液压加载装置可自动为砂箱加载,保证试验外管承受均匀、适当的载荷。该装置符合国家有关法规标准的要求,能实现自动装卸砂,自动为砂箱加载。（图8,表2,参9）     

广义Riesz平均的交换子

讨论了一类Ｒｉｅｓｚ平均与ＢＭＯ函数生成的交换子的Ｌ＾ｐ有界性问题。得到的结果表明在超曲面的高斯曲率不为零的条件下，与经典的Ｂｏｃｈｍｅｒ－Ｒｉｅｓｚ平均有相类似的结果。     

战略性新兴产业背景下高等学校专业结构调整分析

后金融危机时代，在大力发展战略性新兴产业背景下，必须加强高校专业结构调整力度。基于产业结构调整与高校专业结构调整之间的辩证互动关系和国外经验，新形势下，高校专业结构调整的基本原则是：动态、优势、特色和非均衡；其总体思路是，以学生为本，重视学生的个性发展。立足社会需要，努力打造能够适应时代变化和市场需求的高等学校专业课程体系。     

车床的数控改造

普通机床的数控化改造已成为企业提高自身自动化程度的一种重要手段,是中小型机械加工企业技术革新的重要途径。文章阐述了普通车床数控化改造的过程和方法。     

Diallel study of open-pollinated maize varieties in Trinidad

Summary In Trinidad, maize (Zea mays L.) is primarily harvested in the immature stage as green ears for human consumption. The purchase of popular imported hybrid seed has become a substantial component of the economic inputs of maize production. The objectives of this study were to investigate combining abilities and heterotic patterns among available open-pollinated varieties and to assess correlations among five important traits: time to silking, plant height, grain yield, ear size, and marketable ears per hectare. General combining ability was significant for all traits. Specific combining ability was significant for all traits except ear size. Three intervarietal crosses showed moderate levels of heterosis (10–27%), and several yielded similarly to the control hybrids, Pioneer X304 and Pioneer 3078. The cross Acid Soil Tolerant 1991 SA-3 X ICTA Farm Corn was selected as the most suitable base population for mass selection. Phenotypic and genotypic correlations among the five traits studied were all positive and significant. Populations which flowered early were shorter and yielded less than the late flowering and taller populations and population crosses included in this study.     

Breeding two base populations of perennial ryegrass

Summary A program designed to develop two base populations of perennial ryegrass was initiated in 1985 in Galicia. Multitrait mass selection by a base index was practised in two genetic resources groups of wild Galician populations. Plants selected were intercrossed and the two resulting base populations (F and G) were evaluated in two locations at the spaced plant level and in plot trials with the aim of estimating the genetic parameters and the possibilities for future breeding. The two populations did not show significant differences from commercial cultivars. Production characters had low heritabilities (0.01–0.32) in both locations. Seasonal yields had medium to high family heritabilities (0.36–0.73). For the economic traits chosen, the expected genetic advances were important in both populations for summer and autumn growth in Mabegondo and spring and summer-autumn dry matter yield (1^st and 3^rd year) in Puebla de Brollón. Expected genetic advance for early spring growth was 0.62 in population F. In the autumn of 1991 equal numbers of plants, selected at each location by combined family and mass selection from each of these populations, were planted in two polycrosses with the aim of improving the genetic basis and adaptation of these populations.     

Methods,Principles and Problems of CGE Model''s Solving

Computable general equilibrium (CGE)model's solving is important for its reseachers . Though there are many softwares to solve the CGE model, it is very important for its reseachers to understand CGE model's solving principle. The paper introduces the methods,principles and problems of CGE model's solving.The software -MATLAB is used to solve CGE Model, and reseach the existing problem of CGE model's solving.     

播期对玉米早代自交系田间抗病性的影响

对1998－2000年4月中下旬（春播）和6月上旬（夏播）种植的1607份玉米早代系进行田间自然抗性鉴定表明：播期对玉米早代系田间抗病性具有很大的影响，玉米早代自交系大斑病和粗缩病以春播发生较重，而小斑病和茎基腐病以夏播发病较充分。因此，在鉴定玉米早代系田间抗性时应根据鉴定病害对象安排在不同播期进行。     

Genetic analysis of threshability in grain sorghum [Sorghum bicolor (L.) Moench]

The ease with which seeds are detached from panicles is one of the early domestication traits. Genotypes with sticky panicles are hard to thresh, and whenever threshed, the grain tends to remain attached to the glume which reduces market value and processability. This study was conducted to determine the genetic mechanisms underlying the threshability trait in sorghum. Four seed parents and eleven pollinators differing for threshability were intercrossed in Design II mating scheme and the resulting hybrids and the parents were grown in four environments. Threshability was estimated as the ratio of seed yield to panicle weight (TW) and proportion of seeds without sticky glumes (TG). Variation was significant among the entries, inbreds and hybrids with GCA for TG and TW varying markedly. Mean TG for inbred and hybrids of low threshable genotypes was not markedly different indicating that threshability trait is under the control of additive genes with dominant or partially dominant effects. Segregation analysis indicates that the TG trait may be under the control of few major genes with approximately one to three loci affecting the trait.