乙酰甲喹在试验性肝功能损害家兔体内的药动学研究

【目的】比较乙酰甲喹在健康和肝功能损害家兔体内的药动学特征,为临床合理用药提供资料和理论依据。【方法】将12只家兔随机均分为2组,一组为健康对照组,另一组于试验前以0.4 mL/kg剂量皮下分点注射四氯化碳,以复制肝功能损害病理模型。24 h后,对2组家兔以20 mg/kg的剂量耳缘静脉快速注射乙酰甲喹20mg/kg,6 h内不同时间心脏采血8次,用高压液相色谱法测定乙酰甲喹血药浓度,用残数法逐只家兔拟合药-时曲线,以方差分析优选房室模型计算药动学参数。【结果】乙酰甲喹在家兔体内的药动学配置符合无吸收因素一室开放模型,其药-时曲线最佳方程为:C健康=25.564 2 e-0.371 6t,C肝损=24.308 9 e-0.144t。与健康组家兔相比,肝功能损害组家兔药动学参数有显著变化:半衰期t1/2延长166.49%,消除速率常数kel减小61.25%,体清除率CLB减小54.95%,药-时曲线下面积增大155.87%。【结论】家兔肝功能损害后,乙酰甲喹在其体内的消除过程显著减慢,因此在肝脏损害时应相应减小乙酰甲喹的给药剂量或增大给药间隔时间。     

莲心碱对大鼠脑缺血再灌注损伤血清中IL-1、TNFa的影响

目的:观察莲心碱对大鼠局灶性脑缺血/再灌注损伤血清中白介素-1(IL-1)和肿瘤坏死因子a(TNFa)活性的影响,探讨其对大鼠脑缺血再灌注损伤保护作用的机制。方法:线栓法阻塞大鼠大脑中动脉2h/再灌注24h制备大鼠脑缺血再灌注损伤动物模型。将24只SD雄性大鼠,随机分为3组:假手术组、缺血再灌注组和莲心碱3mg·kg-1组,分别于术前30min、再灌注后、再灌注12h舌静脉注射莲心碱3mg·kg-1;再灌注24h后大鼠断头取血,分离血清,采用双抗体夹心ELISA法测定血清IL-1和TNFa的吸光度。结果:大鼠脑缺血2h,再灌注24h后,血清中IL-1和TNFa活性显著增加,莲心碱可显著降低缺血再灌注损伤大鼠血清IL-1和TNFa活性。结论:莲心碱可能通过降低IL-1和TNFa活性而发挥脑缺血的保护作用。     

利用叶绿素荧光预测水蜜桃果实冷害研究

采用叶绿素荧光技术检测冷藏条件下水蜜桃冷害发生进程中初始荧光（Fv）、最大荧光（Fm）、可变荧光（Fv = Fm/Fo）、光化学效率（Fv/Fm）等叶绿素荧光动力学参数的变化,分析了叶绿素荧光参数与果肉出汁率的相关性以及与呼吸作用的关系。研究结果发现,在冷藏过程中,叶绿素荧光参数都呈下降趋势,冷害发生以后,Fm和Fv/Fm下降速度加快,而中途加温处理能够缓解Fm和Fv/Fm降低。同时,Fm和Fv/Fm与果肉出汁率之间存在显著的正相关,利用测定Fm和Fv/Fm能够初步预测冷害的发生情况。     

Responses of Yield Characteristics to High Temperature During Flowering Stage in Hybrid Rice Guodao 6

By sowing at different dates during 2005 and 2006 both in paddy fields and greenhouse, a super hybrid rice combination Guodao 6 and a conventional hybrid rice combination Xieyou 46 (as control) were used to analyze the differences in heat injury index, seed setting rate, grain yield and its components. Guodao 6 showed more stable yield and spikelet fertility, and lower heat injury index than Xieyou 46. Further studies indicated that the spikelet sterility is positively correlated with the average daily temperature and the maximum daily temperature, with the coefficients of 0.8604 and 0.9850 (P<0.05) respectively in Guodao 6. The effect of high temperature injury on seed setting caused by maximum daily temperature was lower than that by average daily temperature during the grain filling stage.     

北京地区夏播玉米低温冷害及其对策初探

在分析北京地区近十几年的冷害与近３６年气候特征的基础上,探讨北京地区夏播玉米生育期间的热量条件及冷害发生的时空分布规律,为减轻冷害提供农业气候背景分析,并提出了北京地区优化种植制度和夏播玉米品种合理布局及其它有效的防御对策。     

Current Concepts in the Management of Acute Spinal Cord Injury

Acute injury to the spinal cord initiates a sequence of vascular, biochemical, and inflammatory events that result in the development of secondary tissue damage. Experimental studies and clinical trials in humans have demonstrated that the extent of this secondary tissue damage can be limited by pharmacologic intervention at appropriate intervals after injury. High doses of methylprednisolone sodium succinate (MPSS) improve the outcome of acute spinal cord injury in humans if treatment is initiated within 8 hours of injury. Starting therapy more than 8 hours after injury is detrimental to outcome. The clinical efficacy of methylprednisolone in improving the outcome of canine spinal cord injuries has not yet been demonstrated and its use by veterinarians is controversial. Many dogs are not seen by a veterinarian within the 8-hour window after injury, and these dogs frequently are treated with nonsteroidal anti-inflammatory drugs or large doses of dexamethasone or prednisone before methylprednisolone treatment can be initiated, thus increasing the risk of severe adverse effects. Other drugs that may provide safer and more effective alternatives to methylprednisolone include thyrotropin-releasing hormone (TRH), the 21-aminosteroids, and kappa opioid agonists. Recent studies suggest that modulation of the influx of inflammatory cells and activation of endogenous microglial cells may provide another means of improving the outcome of acute spinal cord injuries. Many drugs being developed to treat acute spinal cord injury have shown promising results when evaluated experimentally. However, any proposed therapeutic strategy should be evaluated in prospective blinded clinical trials before being adopted in clinics.     

Impact of recreational power boating on two populations of northern map turtles (Graptemys geographica)

• 1. Recreational power boating is growing in popularity in North America. This activity is known to have lethal and sub‐lethal effects on aquatic wildlife and freshwater turtles may be particularly sensitive to this activity.
• 2. This study reports on patterns of traumatic injuries inflicted by powerboat propellers to northern map turtles (Graptemys geographica) from two sites differing in boat traffic intensity in Ontario, Canada.
• 3. The relative vulnerability of turtles was assessed, in light of seasonal patterns in boat traffic, as a function of sex‐ and age‐specific movement patterns, habitat use, and basking behaviour obtained by radio‐telemetry. Population viability analyses (PVA) were also conducted to evaluate the potential demographic consequences of mortality induced by powerboats.
• 4. The prevalence of propeller injuries was two to nine times higher in adult females than in adult males and juvenile females. Patterns of movement, habitat use, and aquatic basking indicated that adult females are more exposed to collisions with boats. PVA showed that boat‐induced mortality in adult females could lead to rapid population extinction if the risk of mortality when hit by a boat is greater than 10%.
• 5. The results of this study showed that recreational power boating is a serious threat to northern map turtles, even under moderate boat traffic. The need to adopt measures restricting boat traffic in areas important to turtles is discussed. Copyright © 2009 John Wiley & Sons, Ltd.

     

乐昌市园林植物冻害调查与分析

调查了经历乐昌市2020年12月—2021年1月低温天气的园林植物的受冻害、需处理和恢复的情况,记录到受冻害的园林植物有124种（含杂交种、变型和园艺品种）,具有受冻害种类较多、外来植物受冻害比例高和同种植物受冻害程度因地或苗而异的特点。受冻害的主要原因除了长时间的低温天气外,还有苗木栽培时间短、引种不科学、管理粗放等。建议遵循适地适树原则,科学选择植物种类,区别选择南北两地种类;尽量使用本地苗圃培育的苗木,少用外来苗木;加强人工管护和灾后处理;提前炼苗。     

2005～2006年冀中南小麦冻害成因分析

分析了冀中南麦区2005年冬前和冬季特殊气候条件下小麦遭受冻害的内在和外在因素,并提出了冀中南麦区预防小麦冻害的基本对策.     

棉花抗逆性鉴定技术标准体系的建立

棉花是中国主要的经济作物,分布区域广,生产周期长,受生态逆境胁迫影响大。培育和筛选抗逆性强的棉花品种是减少逆境灾害的主要途径,而研究棉花品种的抗逆性鉴定技术和标准是至关重要的基础工作。归纳了近年来国内外作物抗逆性鉴定的基本方法,分析了棉花干旱、渍涝、盐碱、高温热害和低温冻害冷害等5种常发易发非生物逆境（生态逆境）抗逆性鉴定的鉴定时期、鉴定方法、鉴定指标和抗逆性判定级别等,总结了抗逆性鉴定标准制定和标准体系建立的基本原则、框架和内容等。提出了进一步研究的基本思路,主要包括：研究基于光谱/高光谱等新技术的快速便捷无损抗逆性鉴定、复合逆境下抗逆性鉴定、利用分子生物学手段直接找出相关抗逆基因并以此来进行抗逆性鉴定等技术。