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41.
Three dogs were presented to us for evaluation of cardiac problems. Electrocardiographic recordings revealed severe tachyarrhythmia and atrial fibrillation with ventricular tachycardia in 2 of the 3 dogs. The echocardiographic findings of the 3 dogs revealed markedly decreased fractional shortening and a marked increase in E-point septal separation. Based on the results of electrocardiographic and echocardiographic evaluation, the 3 dogs were diagnosed as dilated cardiomyopathy (DCM). The dogs were treated with conventional cardiac medication, but cardiac function did not improve and the clinical signs remained. We subsequently attempted treatment with granulocyte-colony stimulating factor (G-CSF; 10 microg/kg, subcutaneously). The specific purpose of G-CSF therapy for DCM was to improve cardiac function and a significant improvement in cardiac function was confirmed. The three dogs had no treatment side effects. This case report suggests that G-CSF might have therapeutic effects for medically refractory DCM in dogs.  相似文献   
42.
Glutathione (GSH) concentrations of oocytes are considered as an important marker of the cytoplasmic maturation. The present study was designed to compare GSH concentrations of in vivo and in vitro matured canine oocytes. In vivo matured oocytes were collected 72 hr after ovulation by flushing fallopian tubes after laparotomy. Ovaries were collected from bitches with different reproductive stages, and collected oocytes were divided into 2 groups according to the size viz. < 120 microm and > 120 microm in diameter and cultured for 72 hr in Tissue Culture Medium-199 supplemented with 10% FBS, 2.2 mg/ml sodium bicarbonate, 2.0 microg/ml estrogen, 0.5 microg/ml FSH, 0.03 IU/ml hCG, and 1% penicillin-streptomycin solution in the presence or absence of 50 microM beta-mercaptoethanol. GSH concentrations were determined by the dithionitrobenzoic acid-glutathione disulfide (DTNB-GSSG) reductase recycling assay. GSH concentrations of immature canine oocytes were 2.9 and 3.8, 3.5 and 6.8, and 3.1 and 6.5 pM/oocyte for < 120 microm and > 120 microm in diameter oocyte groups at anestrous, follicular and luteal stage, respectively (P<0.05). In vivo matured oocytes had significantly higher GSH concentrations compared with in vitro matured oocytes. The GSH content was 19.2 pM/oocyte for in vivo matured oocytes, while 4.1 to 8.1 and 5.7 to 13.2 pM/oocyte for in vitro matured oocytes cultured in the absence or presence of beta-mercaptoethanol, respectively (P<0.05). Presence of beta-mercaptoethanol increased GSH synthesis in canine oocytes cultured in vitro, and oocytes collected from follicular and luteal stage was superior to anestrus oocytes.  相似文献   
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修剪是果树生产中重要的技术手段,要想研究更加合理的修剪技术体系,就必须保证能够对修剪反应有准确、直观和及时的判断,而仿真模拟技术提供了这种可能。以幼龄苹果树为研究对象,采用不同修剪处理对比的方法,在田间试验的基础上,总结修剪反应规律,构建苹果树结构和修剪模型。在此基础上基于Qt框架和OpenGL图形库,开发了单株苹果树修剪仿真软件平台。结合优化算法,通过仿真平台模拟了给定生产目标的修剪方案优化,优化结果对虚拟学习和实际生产提供了可视化指导。  相似文献   
46.
Field experiment was carried out to investigate the effect of soil matric potential (SMP) on tomato yield, evapotranspiration (ET), water use efficiency (WUE) and irrigation water use efficiency (IWUE) under drip irrigation condition in North China Plain. The experiment included five treatments, which controlled SMP at 0.2 m depth immediately under drip emitter higher than −10 (S1), −20 (S2), −30 (S3), −40 (S4) and −50 kPa (S5), respectively, after tomato plant establishment. The results showed that different SMP affected irrigation amount and tomato ET. Irrigation amount decreased from 185 mm (S1) to 83.6 mm (S5) in 2004, and from 165 mm (S1) to 109 mm (S5) in 2005, respectively. The ET decreased from 270 mm (S1) to 202 mm (S5) in both years. However, it was found that SMP did not affect the tomato yield significantly, for the range of SMP investigated. Both WUE and IWUE increased as SMP decreased. The maximum WUE (253 and 217 kg/ha mm) and IWUE (620 and 406 kg/ha mm) were for S5 in 2 years, whereas the minimum WUE (178 and 155 kg/ha mm) and IWUE 261 and 259 kg/ha mm) were for S1 in 2004 and 2005. Based on the above results, therefore, it is recommended that if the tomatoes are well irrigated (SMP is higher than −20 kPa) during establishment, controlling SMP higher than −50 kPa at 0.2 m depth immediately under drip emitter can be used as an indicator for drip irrigation scheduling during following period of tomato growth in North China Plain.  相似文献   
47.
The effects of water deficit in different fruit growth stages on the variation of stem sap flux of 6-year old greenhouse-grown pear-jujube trees were investigated. Treatments included sufficient water supply during the whole fruit-growing period (T1), mild water deficit during the flowering–fruit setting stage (T2), moderate water deficit during the fruit rapid growth stage (T3) and severe water deficit during the fruit maturing stage (T4). Results showed that significant compensation effect on stem sap flux after re-watering was observed in T2, but not in T3 and T4 stages. At the end of rapid growth stage, the diurnal variation of stomatal conductance generally had a similar trend as that of stem sap flux, but with a distinct midday depression from 12:00 to 14:00 p.m. In addition, a linear relationship between the relative available soil water content (RAWC) and the ratio of daily stem sap flux to that of sufficient water treatment was observed (R2 = 0.4489).  相似文献   
48.
Drip irrigation scheduling for tomatoes in unheated greenhouses   总被引:5,自引:0,他引:5  
During the last two decades, energy-saving solar greenhouses without heating systems, about 150-800 m2 (width: 5-10 m, length: 30-80 m) in size, have been widely used in the North of China for vegetable production during cold seasons. The greenhouse is also suitable for use in other countries located in the temperate or warm-temperate zones, especially in the developing countries, because it is inexpensive with a simple structure, and does not need any additional energy for heating in winter. Drip irrigation has been recognized as a sensible method of supplying water inside the greenhouses, and a simple method for drip irrigation scheduling at low cost is urgently required. Using the water-balance method, the authors studied the water consumption of tomato (Lycopersicon esculentum Mill.) and the relationship between evapotranspiration and water surface evaporation measured with 20 cm pan. Research results show that there is no significant water flux at 0.75 m depth when soil water potential is kept higher than -20 kPa at 15 cm depth, and around -20 kPa at 60 cm depth. The accumulative value of evapotranspiration is approximately equal to the accumulative value of water surface evaporation measured using 20 cm pan. Further analysis found that 20 cm pan can be used to determine the water requirement of tomato drip irrigation scheduling in this type of greenhouse.  相似文献   
49.
综述氯酸钾对龙眼催花的效应及其机理,概述应用氯酸钾促使龙眼开花应注意及存在的问题。  相似文献   
50.
鄂薯和华薯系列马铃薯品种是由湖北恩施中国南方马铃薯研究中心和华中农业大学马铃薯团队选育而成的品种.鄂薯系列马铃薯品种大多为中晚熟品种,适合西南山区种植;华薯系列马铃薯品种多为早熟品种,适于华中低山丘陵和平原地区种植.研究对2个系列品种部分晚疫病抗病基因进行了分子标记检测,同时对几个水平抗性相关基因SNP位点进行了检测....  相似文献   
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