模拟热浪期间突然强降温天气对高血压大鼠心血管系统影响的实验研究

通过模拟热浪期间突然强降温天气对高血压大鼠影响的实验研究,探讨热浪期间突然强降温对高血压大鼠心血管疾病的影响机理。应用TME1880气象环境模拟箱模拟了南京2006年6月19日5时至22日11时高温热浪期间突然强降温天气过程,将24只高血压大鼠随机分为实验组(包括热浪组、降温组和复温组)和对照组,每组各6只大鼠。把实验组放入模拟箱内,使其受热浪期间突然强降温天气过程影响,分别在模拟热浪期间突然强降温天气过程55、59和75 h时,先后取出热浪组、降温组和复温组监测基本生理指标;并采用断头采血和摘取心尖,测量各组高血压大鼠的热应激因子(HSP60、SOD、s ICSM-1、HIF-1α)、冷应激因子(NE、EPI、ANGⅡ)、血管收缩因子(ET-1、NO)以及心血管的危险因素(TC、TG、HDL-C、LDL-C和Tn-T)生化指标的含量。结果表明受高温热浪的影响,高血压大鼠的热应激因子除SOD含量明显下降以外其他热应激因子含量均明显增加,冷应激因子均明显下降,血管收缩因子ET-1下降而NO上升,心脑血管危险因素除TG上升以外其余因子均有不同程度的下降。热浪期间突然强降温可导致高血压大鼠热应激因子除SOD上升以外其余均下降,冷应激因子全部上升,血管收缩因子ET-1上升而NO下降,心血管危险因素均上升。通过分析可知,热浪可使得高血压大鼠动脉粥样硬化加剧,热浪期间突然强降温使得NE和ANGⅡ含量明显增加,加剧血压升高。受降温的影响Tn-T明显增多,说明突然的强降温冷刺激导致的血管收缩导致了心肌缺血,加上血脂四项的升高使得高血压大鼠心血管疾病进一步加重。初步探讨了热浪期间突然强降温天气对高血压大鼠心血管疾病的影响。     

湖北陆水湖局部地区鼠类的初步调查

湖北蒲圻陆水湖局部地区鼠类分布和活动情况的初步调查及结果分析。     

New eco-morphological-behavioural approach of the chinchilla rats in the pre-Andean foothills of the Monte Desert (Argentina)

This study characterizes the ecology, behaviour and morphology of populations of Abrocoma schistacea and A. uspallata in north-western Argentina. We carried out live-trapping, tagging and recapture during 2006–2008. Burrow structure and vegetation were described. Diet composition and the activity of chinchilla rats were defined. Both species inhabit rock crevices in the pre-Andean foothills of the Monte Desert. Some of their morphological specializations for saxicolous life, such as foot pads for better traction on rocky surfaces and reduced nails, are convergent with those of other saxicolous species. Both species appear to be diurnal, with activity peaking in the early morning. Dietary analyses suggest trophic specialization by both species. Density of A. schistacea was of 0.15 ± 0.06 individuals ha^?1; with individuals living in groups of 3–4 animals. Given their low abundance, restricted distribution and high level of habitat and food specialization, we urge that populations of this species be protected through effective management.     

Vitamin B12 amplifies circadian phase shifts induced by a light pulse in rats

Vitamin B₁₂ (VB₁₂) is a putative modulator of the human circadian clock, improving entrainability to the 24 h light-dark cycle. The present study was intended to elucidate the mechanism of VB₁₂ action in an animal model. In male rats free-running under constant dim illumination, a single light pulse of 50–1000 lux for 20 min given at circadian time (CT) 20 induced a 0.28 to 1.08 h phase advance and at CT 14 induced a 0.54 to 2.10 h phase delay. A 3 h intracerebroventricular (icv) infusion of 30 nmol VB₁₂ starting 2 h prior to a 20 min 200 lux light pulse significantly amplified phase shifts in comparison with saline-treated or untreated controls. The mean phase advance (1.13 h) was 1.8-fold greater than that of saline-infused controls, whereas the mean phase delay (2.28 h) was 2.9-fold greater. These values were comparable to the maximal phase shifts caused by 1000 lux light pulses in untreated rats. Since the same VB₁₂ treatment alone had failed to induce a phase shift in a previous experiment, these results indicate that VB₁₂ strongly enhanced light pulse-induced phase shifts and thus augmented the entrainability of the circadian clock to light.     

鱼油饲料对自发性高血压大鼠血压血脂心肌收缩力及动作电位的影响

雄性8个月龄自发性高血压大鼠20只,其遗传性高血压及心肌肥大已稳定形成。对照组10只,饲标准饲料,连续80天。实验组10只动物饲混有10％鱼油(C_(20):5n-3,12-20％)的标准饲料80天。每周测量大鼠尾部血压、心率两次。实验开始后第20天,实验组动脉收缩压从210±6mmHg下降到190±10mmHg。此后60天内,稳定在185±10mmHg,比原血压水平降低12％(P<0.05)。对照组的血压,在80天内稳定在210±15mmHg。实验组总胆固醇为73±9mg/dl,较对照组(108±12mg/dl)降低32％(P<0.05);甘油三酯为105±24mg/dl,较对照组(220±58mg/dl)降低51％(P<0.06)。 用标准微电极和张力换能器在左、右心室乳头肌上同时记录动作电位和等长收缩力。结果表明,实验组左心室乳头肌APD_(50)(83±11.2msec)较对照组(112±10.8msec)缩短22％(P<0.05)。APA、RP和APD_(90)没有显著性改变。值得注意的是,尽管统计学上无显著性差异,但实验组的V_(max)较对照组有降低的趋势。右心室乳头肌AP各参数在两组间无明显差异。两组动物心室乳头肌等长收缩力峰值及达峰值的时程也无明显差别。 以上结果提示,10％鱼油对SHR有降低血压,降低血液胆固醇及明显降低甘油三酯的作用。使肥大心肌APD_(50)缩短,对心肌收缩力各参数未见明显影响。     

电刺激迷走背核对大鼠高频心电信号的影响

用心电高频信息检测分析仪研究了电刺激大鼠迷走神经背核(DMV)对心电活动的影响,分析了刺激前、刺激即刻、刺激后4min和刺激后8min高频心电图(HF-ECG)的各项时域值.结果表明:1刺激前心率(427±56)次/min(x-±SD,下同),刺激即刻(191±96)次/min,与刺激前相比心率显著降低(P<0.01),刺激后心率有回升的趋势.2刺激前QRS波宽( 导联,下同)(14.5±1.3)ms,刺激即刻(19.0±3.1)ms,与刺激前相比QRS波宽显著延长(P<0.01).3刺激前QRSVp-p(0.52±0.12)mv,刺激即刻(0.37±0.10)mv,与刺激前相比显著降低(p<0.05).4刺激前切迹数(0.20±0.4)个,刺激即刻(0.7±0.8)个,与刺激前相比显著增多.5刺激前100Hz～1000Hz,80Hz～300Hz,100Hz～250Hz,150Hz～250Hz各频段的高频相对能量分别为:(21.24±16.78)%,(32.56±20.60)%,(20.91±16.41)%,(4.68±4.81)%,刺激即刻分别为:(2.81±1.91)%,(6.86±3.96)%,(2.69±1.90)%,(0.34±0.28)%,与刺激前相比,各频段相对能量显著降低.结果表明刺激大鼠的DMV对HF-ECG的时域值和频域值有明显影响,DMV对心脏电活动有调节作用.     

SDH自愈环的业务量优化设计

对现有的五种双向自愈环的环容量和路由算法进行了比较,并分析了计算机模拟结果,得到了规划环网时能有效降低环容量配置的路由算法。     

Wistar系大鼠自发性脑积水动物模型建立的初探

继１９８９年１０月在我所实验动物中心普通级Ｗｉｓｔａｒ鼠中发现一雄性脑积水幼鼠之后，１９９０年９月又在该鼠群中发现一窝三只脑积水幼鼠，遂将此窝内其他表型正常鼠育成基础种鼠群，并以此作为Ｆｏ代动物，于同年的１１月１９日开始建立此模型的近交育种研究。经过一年多的试繁与选育，仔代脑积水发生率从始发代的１．９％上升到１７．Ｏ％，累积获得脑积水动物４４只，其中雄性１９只，雌性２５只，雄雌之比为０．８：１。由于该性状系受隐性、致死基因控制，故建立了以“Ｐ×Ｏ”为辅助系统，“ｂ×ｓ”为主系统的育种保种方法。此脑积水动物的生物学特征为：最早发现为１日龄，最早死亡日龄为＜２０日龄。早期表现为脑部隆起肿大成泡状，生长发育较同窝正常鼠稍缓慢，之后随着日龄的增加，病情加重，脑部隆起更甚，体消瘦，被毛杂乱竖立，弓背，目光呆滞无神，肛门及腹面常不清洁，严重者步伐不稳，四肢麻痹，侧卧于宠底，常出现阵发性颤抖，直至衰竭死亡。此脑积水为生理性自发，与人类脑积水相似，且孕期短，窝（代）发生率较高，脑标本体积较大，可望成为又一理想的研究人类脑积水的动物模型。     

党政干部质量考核的数学模型

本文给出一种考核党政干部质量优劣的数学模型。按照该模型,从程度分析和集值统计出发,运用聚类分析方法,引入增益函数概念,通过对争议度δ_(iq)(λ,τ)、上偏差α_(iq)(λ)、下偏差β_(ip)(τ)的分析、比较,达到择优选拔干部的目的。