Dose requirement and cardiopulmonary effects of diluted and undiluted propofol for induction of anaesthesia in dogs

ObjectiveTo compare the dose, cardiopulmonary effects and quality of anaesthetic induction in dogs using propofol (10 mg mL^–1) and diluted propofol (5 mg mL^–1).Study designRandomized, blinded, clinical study.AnimalsA total of 28 client-owned dogs (12 males/16 females).MethodsFollowing intramuscular acepromazine (0.02 mg kg^–1) and methadone (0.2 mg kg^–1), propofol (UP, 10 mg mL^–1) or diluted propofol (DP, 5 mg mL^–1) was administered intravenously (0.2 mL kg^–1 minute^–1) by an anaesthetist unaware of the allocated group to achieve tracheal intubation. Sedation, intubation and induction quality were scored from 0 to 3. Pre- and post-induction pulse rate (PR), respiratory rate (f_R) and systolic (SAP), mean (MAP) and diastolic (DAP) arterial blood pressure were compared. Time to first breath and induction dose were recorded. Data were analysed for normality and Mann–Whitney U or Student t tests were performed where appropriate. Significance was set at p < 0.05. Data are presented as mean ± standard deviation or median (range).ResultsThe propofol dose administered to achieve induction was lower in the DP group (2.62 ± 0.48 mg kg^–1) than in the UP group (3.48 ± 1.17 mg kg^–1) (p = 0.021). No difference was observed in pre- and post-induction PR, SAP, MAP, DAP and f_R between groups. The differences between post-induction and pre-induction values of these variables were also similar between groups. Time to first breath did not differ between groups. Sedation scores were similar between groups. Quality of tracheal intubation was marginally better with UP 0 (0–1) than with DP 1 (0–2) (p = 0.036), but overall quality of induction was similar between groups [UP 0 (0–1) and DP 0 (0–1), p = 0.549].Conclusion and clinical relevanceDiluting propofol reduced the dose to induce anaesthesia without significantly altering the cardiopulmonary variables.     

鸡肿瘤坏死因子的诱生及活性检测

通过对鸡静脉注射卡介苗 (BCG)和脂多糖 (L PS) ,应用 L92 9细胞检测鸡体外周血清、脾细胞和外周血白细胞肿瘤坏死因子 (TNF)活性 ,表明外周血清 TNF活性最高 ,其次是脾细胞 ,而外周血白细胞 TNF活性最低。本研究也表明在正常鸡的外周血液中有少量的 TNF     

多年生黑麦草高频再生体系的建立及优化

从外植体预处理方式、基本培养基、激素浓度等方面着手,对多年生黑麦草愈伤组织诱导、继代、不定芽分化及再生过程中的影响因素进行了研究,提高了再生频率。结果如下：切取胚端半粒种子,经75%乙醇处理1min,0.1%HgCl处理15min,在经无菌水清洗4～6次后接种方式较好;愈伤组织诱导培养基以MS＋2,4—D 8.0 mg/L（或另添加甘露醇25 g/L）为佳;愈伤组织接种于MS＋2,4—D 8.0mg/L＋甘露醇25 g/L上进行1～2次继代后于NB＋6—BA2.0 mg/L上进行分化;不定芽转接至MS＋6—BA2.0 mg/L上进行扩繁或于1/2MS＋NAA0.5mg/L＋IAA0.5mg/L上进行生根。     

维他昔布咀嚼片体外溶出度的测定

为了建立了维他昔布咀嚼片体外溶出度的测定方法,以0.8％十二烷基硫酸钠溶液为溶出介质,采用桨法(50 r/min),用紫外-可见分光光度法测定溶出度.结果显示,维他昔布浓度在0.002496 ～0.017472 mg/mL范围内,与吸收度呈良好的线性关系(r=0.9995),加样回收率为102.9％(RSD为1.36％),三批样品30 min时溶出度在80％以上.建立的溶出度测定方法重现性,均一性良好,样品溶出度大于80％,可用于维他昔布咀嚼片中溶出度的测定.     

用二乙氨二硫代甲酸银分光光度法测定畜禽饮用水中的砷

畜禽饮用水中砷在锌和酸作用产生新生态氢。在碘化钾和氯化亚锡存在下,使五价砷还原为三价砷。三价砷与新生态氢生成砷化氢气体。通过乙酸铅棉花去除硫化氢的干扰,然后与溶于三乙醇胺-三氯甲烷中的二乙氨基二硫代甲酸银作用,生成棕红色的胶态银,比色定量。结果试样含砷量m与吸光度B呈良好的线形关系,其回归方程为m=3.884 6×B-0.215 2,相关系数r=0.999 3,检出限为0.01 mg/l,对畜禽饮用水中的砷进行测定,相对标准偏差1.3。结论:方法灵敏,结果准确,适用于畜禽饮用水中砷的快速测定。     

利用信息肽诱导和Cre/LoxP系统构建猪链球菌基因缺失株

为建立一种高效的猪链球菌(Streptococcus suis)基因缺失方法,本研究利用信息肽诱导DNA片段转化和Cre/LoxP系统去除抗性基因这两种技术,通过在S.suis 05ZYH33的ssu05_1921基因上、下游片段和壮观霉素抗性基因(spc)片段之间引入LoxP位点,采用信息肽GE9诱导构建的DNA片段转化S.suis并发生重组,经抗性筛选快速获得spc替代ssu05_1921基因的缺失株;进一步引入pSET6s/P_tufA-cre质粒表达Cre重组酶作用于LoxP位点,去除spc基因,产生无痕ssu05_1921基因缺失株,经测序和RT-PCR验证缺失正确。本研究建立的该方法简单、快捷、阳性率高,为构建S.suis基因缺失株、研究S.suis致病机制提供了新的选择。     

红三叶新品系组织培养和植株再生

利用红三叶(Trifolium pratense L.)新品系无菌苗不同部位,通过愈伤组织诱导及分化途径获得再生植株.结果表明:子叶、下胚轴、叶柄、叶片及根段在MS+0.5 mg·L-1 6-BA+1～2 mg·L-1 2,4-D培养基上都极易诱导出愈伤组织.最佳继代培养基为MS+0.5 mg·L-1 6-BA+1.0 mg·L-12,4-D,添加2,4-D比NAA更利于愈伤的增长和保存;最佳分化培养基为MS+0.75 mg·L-1 6-BA+0.5 mg·L-1 NAA,最高分化率为16.67％,且分裂素6-BA优于KT,6-BA与NAA组合比与IBA组合更有利于红三叶愈伤组织的分化;茎芽增     

植物诱导抗性的分子机制研究进展

诱导抗性已成为植物病虫害防治的新手段,其广谱性和对环境的安全性使它受到广泛的关注。文章综述了国内外植物诱导抗性近年来的研究进展,分析了它的一般概念、诱导因子和机制以及近年来发现的与抗性有关的物质等。     

烟蚜茧蜂Aphidius gifuensis滞育诱导研究

研究了不同温度、光周期以及温光组合条件对烟蚜茧蜂滞育诱导的效果。结果表明,僵蚜形成前,各种温度、光周期及温光组合条件均著的作用。僵蚜形成后,低温可大量诱导产生滞育,０℃处理３０ｄ,６０％以上个体进入滞育,而光周期的诱导作用仍不明显。作者认为你温是引起烟蚜茧蜂滞育的主要因素,处理的敏感时期为老熟幼虫－预肾期。滞育虫态为肾。