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21.
【目的】建立羊踯躅嫩叶离体培养及植株高效再生体系。【方法】以羊踯躅新生嫩叶为外植体,筛选嫩叶愈伤组织诱导、再分化及生根培养基,并以再生植株茎节为试材,建立高效植株再生体系。【结果】最适合羊踯躅嫩叶愈伤组织诱导的培养基为1/2 DR+2.40 mg/L 2ip+0.80 mg/L NAA,诱导率为99.5%;愈伤组织再分化的最佳培养基为1/2 DR+2.90 mg/L 2ip+0.01 mg/L NAA+1.75 mg/L KT,分化率为99.7%;适宜生根的培养基为1/4 DR+0.06 mg/L ZT+0.02 mg/L NAA,生根率达99.0%。利用再生植株茎节的快繁结果表明,在28 d的培养周期内,每节段平均增殖达5倍以上。【结论】成功建立了羊踯躅嫩叶愈伤组织诱导、再分化芽苗和植株高效再生体系,可以满足羊踯躅工厂化育苗的需要。 相似文献
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为探析水-热-盐关系以及植被对盐碱田改良的意义,利用2008年8月2日-8月6日在内蒙古杭锦旗黄河灌区盐碱田进行的试验观测数据,主要通过方差分析与典型相关分析方法对3个样地(裸地、紫花苜蓿地和玉米地)土壤温度(0-30cm土层)、湿度(0-20cm土层)、盐度(0-100cm土层)的动态变化进行了分析。结果表明,3个样地的温(度)-湿(度)-盐(度)动态基本呈现裸地苜蓿地玉米地的格局;0-5cm地温与耕作层(0-20cm)的土壤水分具有显著相关关系,是0-30cm土层内地温驱动水盐动态的主要热力因子;植物能够减少土壤表层积盐,并可以降低碱化度;苜蓿地比玉米地具有更低的钠吸附比值。在盐碱地区选择耐盐碱牧草品种开展草田轮作,有益于盐碱土壤的改良与利用。 相似文献
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Comparisons were made between the amounts of abamectin and total radioactivity recovered from Spodoptera littoralis and Heliothis armigera larvae after topical application of [3H]abamectin. Penetration (as shown by wash-off experiments) did not differ significantly between the Spodoptera instars. Significantly more abamectin was recovered from ventral nerve cord samples of larvae showing symptoms of poisoning than from larvae not showing these symptoms. Fifth-instar S. littoralis larvae had a significantly lower proportion of radioactivity as abamectin in the ventral nerve cord than in sixth-instar S. littoralis or fifth- and sixth-instar H. armigera. The proportion of radioactivity present as abamectin (but not total radioactivity) was significantly increased when the fifth-instar S. littoralis larvae were pre-treated with piperonyl butoxide (PB) suggesting that the relative insensitivity of fifth-instar S. littoralis larvae to abamectin is due at least in part to greater metabolism, particularly by microsomal oxidases. Fat body samples consistently had a greater proportion of radioactivity as abamectin than the nerve cord and the former may act as storage sites for abamectin. 相似文献
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ROBERT H. WRIGLEY BVSc MS DVR MRCVS RICHARD D. PARK DVM PHD LINDA J. KONDE DVM JACK L. LEBEL DVM PHD 《Veterinary radiology & ultrasound》1987,28(6):208-212
Photographic subtraction was made of 38 canine portal venograms to remove the images of the overlying abdominal structures and enhance the radiographic contrast of portal veins. The improved visual quality of the subtracted portogram aided in the detection of portosystemic shunts and intrahepatic portal veins. The subtraction studies revealed portosystemic shunts not detected on the initial portal venogram. 相似文献
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Nicola Grint BVSc DVA DiplECVA MRCVS Dylan Gorvy BSc BVSc PhD CertES MRCVS Alexandra Dugdale MA VetMB DVA DiplECVA MRCVS 《Journal of Equine Veterinary Science》2007,27(5):221-227
A 13-year old Thoroughbred cross gelding (528 kg) underwent lameness investigation. Because of his temperament, general anesthesia was required to facilitate ultrasound of the left fore fetlock and intra-articular medication of three joints. Anesthesia was induced with ketamine/diazepam after acepromazine/detomidine premedication. Anesthesia was maintained for 40 minutes with a guaifenesin/detomidine/ketamine intravenous infusion. Recovery from anesthesia was initially uneventful, although of a moderate duration (70 minutes). Once standing, the horse proceeded to box walk in an agitated state and became recumbent on two occasions. The horse was manually restrained, at which time its rectal temperature was 41.8°C. Cooling measures were employed (fans, ice-water enemas, wet rugs, intravenous fluid therapy (IVFT), and topical application of surgical spirit) until rectal temperature reached 38.7°C. IVFT was continued for a further 16 hours. Four days after recovery from anesthesia, bilateral triceps, deltoideus, trapezius, and rhomboideus muscle swelling was observed. Blood creatinine kinase was elevated (24,898 IU/L). Treatment for postanesthetic myopathy was initiated (hot packing of the muscle groups, topical dimethylsulfoxide [DMSO] cream application, and oral phenylbutazone). Myoglobinuria was not observed at any time. Muscle swelling decreased over the following 3 days. The horse was discharged on day 11 and has since returned to work. 相似文献
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K. Kusano DVM R.A. Curtis BSc SMIEEE C.A. Goldman BScAgr D.L. Evans BVSc PhD 《Journal of Equine Veterinary Science》2007,27(8):362-368
Analysis of individual breaths after exercise has potential for pulmonary function testing. The aims of this study were to investigate the dependence of measurements of pulmonary function in single breaths on time postexercise and tidal volume (VT) after treadmill exercise. Five Thoroughbred horses without evidence of airway disease were used. Horses had been previously acclimated to treadmill exercise and to wearing a face mask. A Quadflow spirometer recorded airflow rates continuously during 90 seconds after intense treadmill exercise to fatigue. Indices of function were based on ratios of times within each breath and analyses of the shape of relative flow–time curves within inspiration and expiration. Restricted maximum likelihood, general linear regression, repeated-measures one-way analysis of variance (ANOVA), and two sample t-tests were used, with statistical significance at P < .05. Time postexercise had no effect on several ratios based on time for inspiration (TI) and expiration (TE), and times to peak flows (TI/TT, TE/TT, TE/TI, Tpef [peak expiratory flow]/TE, and Tpif [peak inspiratory flow]/TI). Many variables were significantly dependent on VT. Occasional big respiratory cycles with VT more than 10% greater than in the previous breath had significantly different means for relative flow (Rf)/(TE/TI), epz50% (50% of the time from Tpef to end of expiration), epz75% (75% of the time from Tpef to end of expiration), and ipz75% (75% of the time from Tpif to end of inspiration). Predicted means for these variables differed by 10–20%. This study establishes guidelines for the selection of breaths after exercise, and describes a new approach to measurement of relative flow and time relationships. It was concluded that several time-based ratios have potential for measuring pulmonary function. However, care is needed when selecting breaths for calculation of most of the new relative flow–time variables. 相似文献