红景天对心肌梗死大鼠缺血心肌血管新生作用及对VEGF的影响

目的:探讨中药红景天对急性心肌梗死大鼠缺血心肌血管新生作用及其对血管内皮生长因子(EGF)蛋白和mRNA表达的影响.方法:52只SD大鼠随机分成单纯手术组、术后给药组、提前给药组、假手术组和正常对照组.采用开胸结扎冠状动脉左前降支的方法建立心肌梗死模型,4周后处死动物.Ⅷ因子免疫组化染色后对各组大鼠梗死边缘区微血管进行计数;免疫组化技术及Western blot技术检测各组缺血心肌VEGF蛋白质水平表达变化;逆转录多聚酶链反应(RT-PCR)法检测缺血心肌VEGF mR-NA表达变化.结果:术后给药组和提前给药组血管计数均较单纯手术组增多(P＜0.01),且提前给药组明显多于术后给药组(P＜0.01);术后给药组和提前给药组缺血心肌VEGF及其mRNA表达较单纯手术组增加(P＜0.01),提前给药组缺血心肌VEGF及其mRNA表达明显高于术后给药组(P＜0.01).结论:红景天能够促进心梗后大鼠缺血心肌血管新生,其作用机制可能与上调局部心肌VEGF及其mRNA表达有关.预给红景天可能增强对心梗大鼠的上述作用.     

翻白草对大鼠和家兔高血脂模型的降血脂作用

目的探讨翻白草对高血脂大鼠和家兔的降血脂作用。方法采用Wistar大鼠60只（其中50只为高脂饲料诱导成高血脂动物模型,10只为空白对照组）,家兔36只（其中30只为高脂饲料诱导成高血脂动物模型,6只为空白对照组）。随机分为6组（翻白草大、中、小3个剂量组,模型组,脂必妥对照组,空白对照组）。连续给药6周,分别于给药后第4周、第6周采血,检测血清中胆固醇（TC）、甘油三脂（TG）及低密度脂蛋白（LDL）浓度。结果翻白草各给药组与模型组比较,给药后第4周,翻白草可降低高血脂大鼠和家兔血清中TC、TG、LDL的含量（P〈0.05）;给药后第6周,可显著降低高血脂大鼠和家兔血清中TC、TG、LDL的含量（P〈0.01）。结论翻白草具有很好的降血脂作用。     

菖远胶囊给大鼠长期大剂量用药的安全性评价

目的：研究菖远胶囊对大鼠长期大量用药后的安全性影响。方法：通过对大鼠连续灌胃菖远胶囊13周、26周和停药4周,分别与正常对照组比较血液、生化、病理学检查结果。结果：①菖远胶囊各剂量组给药后5～30 min动物自主活动有所减弱,30 min后自主活动逐渐恢复正常,各剂量组大小便颜色偏深,高剂量组比较明显,停止给药后,上述症状均恢复正常;②大鼠血液细胞学、生化学指标中有个别指标在给药初期（13周）出现明显差异,继续给药至26周,未见明显异常,停止给药后恢复正常;高剂量组动物体重有一定降低,个别脏器质量及指数增大,停药4周后均能恢复正常;病理检查结果示,菖远胶囊各剂量组主要脏器未见由药物引起的病理学改变;整个实验期间各组动物未见死亡;③大鼠长期给予菖远胶囊的安全剂量为4.0 g/kg。结论：菖远胶囊对动物的毒性较低,是值得开发的一个中药新药。     

镁离子联合金雀异黄素对自发性高血压大鼠血压的影响

目的:探讨镁离子联合金雀异黄素对自发性高血压大鼠血压的影响。方法:选用雌性6周自发性高血压大鼠28只,饲养7d后测量大鼠初始收缩压(SBP)及心率(HR),应用双盲分组原则,将大鼠分成对照组、镁离子组、金雀异黄素组、及联合组,每组各7只。饲养7d后,取一次性注射器,消毒抽取药物,暴露尾部及血管,进行注射。每7d注射一次,连续注射4周。比较各组大鼠SBP、HR、hs-CRP、MCP-1、vWF、血管紧张素(AngⅡ)。结果:给药前四组大鼠SBP水平比较无差异(P0.05)。给药后对照组SBP水平高于其他三组(P0.05),镁离子组与金雀异黄素组比较无差异(P0.05),联合组大鼠在给药1周、2周、4周后SBP水平显著低于其他三组(P0.05)。给药前四组大鼠心率比较无差异(P0.05)。给药后对照组、镁离子组、金雀异黄素组与治疗前相比无差异(P0.05),联合组低于治疗前(P0.05)。给药第2、4周联合组HR水平低于其他三组(P0.05)。联合大鼠hs-CRP水平显著降低(P0.05),MCP-1、vWF水平显著升高(P0.05)。给药前各组大鼠AngⅡ水平比较无差异(P0.05),给药2周、4周联合组AngⅡ水平显著降低(P0.05)。结论:镁离子联合金雀异黄素能提高自发性高血压大鼠血管顺应性,减少炎症反应,预防动脉粥样硬化,降低血压。     

RhPTH(1-34)和双磷酸盐交替联合应用对去势大鼠骨质疏松模型治疗的实验研究

目的:研究联合应用重组人甲状旁腺素(1-34)和双磷酸盐对双侧卵巢切除(OVX)骨质疏松大鼠模型的治疗作用.方法:选用3月龄健康SD雌性大白鼠40只作为实验动物,随机分为五组:假手术组(S组)、卵巢切除组(o组)、OVX +RhPTH(1-34)组(R组)、OVX+阿仑磷酸钠组(A组)、OVX+联合用药组(RA组).术后12周开始给药,持续给药6周.给药后6周取血行相关生化指标检测,取股骨进行骨密度测定、骨组织形态计量学分析.结果:O组的大鼠股骨骨密度值较假手术组有明显减少,血清磷、骨钙素和血清雌二醇水平减少(P＜0.01),血清碱性磷酸酶水平增加(P＜0.01),使用甲状旁腺素和阿仑膦酸钠治疗后,大鼠股骨骨密度值、血清磷、骨钙素和血清雌二醇水平增加,血清碱性磷酸酶水平相应下降,尤其是两种药物联合应用后效果更为明显(P＜0.01);荧光双标显示,O组骨形成速率较R组及RA组低(P＜0.05),S组、O组、A组骨形成速率无明显差别(P＞0.05).结论:联合应用RhPTH(1-34)和双磷酸盐可以减少去卵巢大鼠骨量的丢失,预防骨质疏松的发生.     

小檗碱对缺血性脑梗死大鼠氧化应激/炎症反应、血管生成的作用研究

摘要 目的：探讨小檗碱对缺血性脑梗死大鼠氧化应激/炎症反应、血管生成的作用。方法：选取60只SPF级SD大鼠,随机分为对照组、模型组和小檗碱组各20只。建立大鼠脑缺血再灌注损伤模型。术后及给药后7d采用Longa标准评分评估大鼠神经功能。检测各组大鼠脑组织的抗氧化活性和炎症因子水平。采用免疫组化检测脑缺血再灌注皮质微血管密度（MVD）。采用实时定量聚合酶链反应（qRT-PCR）检测低氧诱导生长因子- 1 （HIF-1 ）和血管内皮生长因子（VEGF） mRNA表达水平。采用蛋白免疫印迹试验检测VEGF和HIF-1 蛋白表达水平。结果：模型组和小檗碱组大鼠术后具有神经功能缺损症状表现,Longa评分均高于对照组。给药7 d后,模型组和小檗碱组大鼠Longa评分均高于对照组（P＜0.05）,且小檗碱组大鼠Longa评分低于模型组（P＜0.05）。与对照组比较,模型组丙二醛（MDA）水平显著升高,而谷胱甘肽过氧化物酶（GSH-Px）和超氧化物岐化酶（SOD）活性显著降低（P＜0.05）。与模型组比较,小檗碱组MDA水平显著降低,而GSH-Px和SOD活性显著升高（P＜0.05）。与对照组比较,模型组白细胞介素-1β（IL-1β）、肿瘤坏死因子-α（TNF-α）水平显著升高（P＜0.05）。与模型组比较,小檗碱组IL-1β、TNF-α水平显著降低,差异有统计学意义（P＜0.05）。给药7 d后,模型组和小檗碱组MVD、VEGF mRNA和HIF-1 mRNA表达水平均高于对照组（P＜0.05）,而小檗碱组MVD、VEGF mRNA和HIF-1 mRNA表达水平高于模型组（P＜0.05）。给药7 d后,小檗碱组和模型组VEGF和HIF-1 蛋白表达水平均高于对照组（P＜0.05）,而小檗碱组VEGF和HIF-1 蛋白表达水平高于模型组（P＜0.05）。结论：小檗碱通过抑制氧化应激/炎症反应、促进血管生成从而达到脑保护作用,其机制可能与激活HIF-1 /VEGF信号通路有关。     

醋酸铜诱导家兔排卵前LH峰过程中下丘脑μ—阿片受体密度的变化

下丘脑β-内啡肽（β-EP）活动减弱是排卵前GnRH／LH峰形成的重要因素，为了解下丘脑μ-阿片受体是否参与了这一过程，本文利用放射受体自显影结合计算机图像处理，观察醋酸铜诱导家兔排卵前LH峰过程中下丘脑μ-受体密度变化。给新西兰雌兔注射1％醋酸铜0．9ml（醋酸铜组）或生理盐水（对照组），于注射后不同时间处死，观察下丘脑内侧基底核（MBH）及视前内侧区（MPO）的μ-受体密度变化，结果表明：醋酸铜组给药后1hMPO部位μ-受体密度明显增加（P＜0．05），于给药后3及3．5h明显减少，LH峰出现。MBH部位μ-受体密度变化和MPO部位相似，对照组μ-受体及LH水平无明显波动。相关分析表明：MBHμ-受体密度变化和血LH水平呈显著负相关（γ＝-0．5481，P＜0．01）。上述结果表明下丘脑μ-受体减少与排卵前LH峰形成密切相关。     

土茯苓对肾性高血压大鼠血压的调节作用和机制

目的观察土茯苓对肾性高血压大鼠血压及血液内血管活性物质的调节作用。方法用两肾两夹法造大鼠高血压模型,将造模成功的大鼠按收缩压分层,分成模型对照组、高（土茯苓6g／ks）、中（土茯苓3g／kg）、低（土茯苓1．5g／kg）剂量组和阳性组（卡托普利5mg／kg）;试验期间各组经口灌胃给予相应药物,每日1次,连续4周。每周测定血压1次,末次给药后,测定大鼠血液中ANP、NO、ET、CGRP和AnglI水平。结果土茯苓显著降低了肾性高血压大鼠SBP、DBP和MBP（P＜0．05,P＜0．01）,同时显著降低了ANP、ET的水平（P＜0．05,P＜0．01）,升高了NO的水平（P〈0．05）。结论土茯苓具有一定的降血压作用,其作用途径可能通过降低ANP、ET和升高NO的水平,而发挥血压调节的作用。     

有氧运动对非酒精性脂肪肝大鼠肝细胞PPAR琢mRNA 表达的影响*

目的：研究有氧运动对非酒精性脂肪肝大鼠肝细胞PPARα表达的影响,探讨运动对非酒精性脂肪肝的保护防治作用.方法：36只雄性SD大鼠随机分为对照组,高脂组和高脂运动组.后两组喂食普通饲料的同时在实验前三周给予脂肪乳剂灌胃,以诱发脂肪肝.七周有氧运动后测大鼠体重、肝湿重、测血浆TC、TG、ALT、SOD及MDA水平;采用荧光定量PCR法测肝细胞PPARα mRNA的表达水平.结果：1）与对照组相比,高脂组TC、TG显著升高（P＜0.05,P＜0.01）,高脂运动组均无显著性差异.高脂组TC、TG显著高于高脂运动组（P＜0.01,P＜0.01）.2）高脂组PPARα mRNA表达显著低于对照组（P＜0.05）和高脂运动组（P＜0.01）;高脂运动组显著高于对照组.3）高脂组肝小叶结构模糊,肝窦界限不清,汇管区结构模糊,肝细胞肿胀,有空泡样改变,肝脂肪变性.高脂运动组肝脏仍有脂肪积聚,但肝细胞空泡消失,呈好转趋势.4）高脂运动组MDA显著低于高脂组（P＜0.01）;高脂运动组SOD显著高于高脂组（P＜0.01）.结论：运动可以通过上调PPARαmRNA来促进脂肪酸氧化、降低血脂,从而有效预防肝细胞脂肪变性.     

芪参地黄颗粒对实验性自身免疫性重症肌无力大鼠B细胞介导的免疫机制研究

摘要 目的：探讨芪参地黄颗粒对实验性自身免疫性重症肌无力（EAMG）大鼠B细胞介导的免疫机制。方法：通过Rα97-116肽段和完全弗氏佐剂免疫,成功将30只Lewis大鼠构建EAMG模型,将EAMG大鼠随机分为模型组、芪参地黄颗粒低、中、高剂量组和阳性药组,每组6只。进一步观察大鼠体重及临床症状,检测血清中乙酰胆碱受体抗体（AChR-Ab）含量、脾脏组织CD19和CD27的蛋白表达、B淋巴细胞刺激因子（BAFF）、B细胞趋化因子CXC配体13（CXCL13）、C-X-C趋化因子受体5型（CXCR5） mRNA表达。结果：经给药治疗后芪参地黄颗粒低、中、高剂量组和阳性药组与模型组相比体重增加（P＜0.05）,临床症状评分均下降（P＜0.05）。经给药治疗后,与模型组相比,芪参地黄颗粒低、中、高剂量组血清中AChR-Ab含量均降低（P<0.05）,芪参地黄颗粒中、高剂量组脾脏组织CD27蛋白表达、CD19蛋白表达和BAFF mRNA表达降低（P＜0.05）,芪参地黄颗粒高剂量组脾脏组织CXCL13和CXCR5 mRNA表达降低（P＜0.05）,且芪参地黄颗粒中、高剂量组脾脏组织CD19蛋白表达较阳性药组下降（P＜0.05）。结论：芪参地黄颗粒通过降低EAMG大鼠CD19和CD27蛋白、BAFF、CXCL13和CXCR5 mRNA的表达,减少B细胞的分化增殖,抑制B细胞产生AChR-Ab,减少对乙酰胆碱受体的破坏,使EAMG大鼠体重增加,临床症状得到改善。     

Thermal stability of proteins

The maximum melting points of 14 proteins in respect to pH are reported, the correlation coefficient between the hydrophobic index and the melting point was +0.622, and that between the average residue volumes and the melting points was +0.960. The correlation coefficient between the average residue volume and the hydrophobic index was +0.697. The least square relation between the melting points of the proteins and hydrophobic index and the average residue volumes considered as independent variables yielded a positive coefficient for the average residue volume and a negative coefficient for the hydrophobic index.     

Thermal behaviour of crustaceans

Specific thermoreceptors or putative multimodal thermoreceptors are not known in Crustacea. However, behavioural studies on thermal avoidance and preference and on the effects of temperature on motor activity indicate that the thermosensitivity of crustaceans may be in the range 0.2-2 degrees C. Work on planktonic crustaceans suggests that they respond particularly to changes in temperature by klinokinesis and orthokinesis. The thermal behaviour of crustaceans is modified by thermal acclimation among other factors. The acclimation of the critical maximum temperature is an example of resistance acclimation, while the acclimation of preference behaviour may be classified as capacity acclimation of some other function. In crustaceans, the use of the concepts stenothermy and eurythermy at the species level is questionable, and it is not possible to divide crustacean species into thermal guilds as suggested for fishes. Thermal preference behaviour contributes to fitness in different ways in different species, often by maximising the aerobic metabolic scope for activity. In crustaceans the peripheral nervous system seems to have retained the capacity for thermosensitivity and thermal acclimation independently of the central nervous system control of behaviour.     

Thermal torsion of F-actin

The equipartition theorem is used to calculate the mode amplitudes for F-actin thermal torsion. The amplitudes phi n are found to scale as n-1, (EI)-1/2, and L1/2, where n is mode number, EI is actin bending stiffness, and L is filament length. Depending on conditions, the amplitude can be as large as 15 degrees; this is discussed briefly in terms of skeletal muscle mechanics.     

Thermal degradation of glucosinolates

Three glucosinolates (allyl-, benzyl- and 2-phenethyl-) were shown to degrade thermally in a GC column to yield products identical with those obtained conventionally on enzymic decomposition, namely nitriles and isothiocyanates. Nitriles were formed more readily at 125° but the facility for isothiocyanate production varied slightly with the glucosinolate; 2-phenethylglucosinolate was the most labile of those studied yielding isothiocyanate at a column temperature of 150°. Temperature was confirmed as the cause of degradation by isolated heated-tube experiments. The results have significance both with regard to analytical methodology for glucosinolates and their products, and with regard to furthering understanding of the mechanisms of glucosinolate degradation.     

Thermal equilibrium of goats

The effects of air temperature and relative humidity on thermal equilibrium of goats in a tropical region was evaluated. Nine non-pregnant Anglo Nubian nanny goats were used in the study. An indirect calorimeter was designed and developed to measure oxygen consumption, carbon dioxide production, methane production and water vapour pressure of the air exhaled from goats. Physiological parameters: rectal temperature, skin temperature, hair-coat temperature, expired air temperature and respiratory rate and volume as well as environmental parameters: air temperature, relative humidity and mean radiant temperature were measured. The results show that respiratory and volume rates and latent heat loss did not change significantly for air temperature between 22 and 26 °C. In this temperature range, metabolic heat was lost mainly by convection and long-wave radiation. For temperature greater than 30 °C, the goats maintained thermal equilibrium mainly by evaporative heat loss. At the higher air temperature, the respiratory and ventilation rates as well as body temperatures were significantly elevated. It can be concluded that for Anglo Nubian goats, the upper limit of air temperature for comfort is around 26 °C when the goats are protected from direct solar radiation.     

Thermal transitions of proteins

A new method for monitoring the thermal transitions of proteins is described. An unbuffered solution of native protein shows a significant and fairly abrupt change in pH as the protein becomes heat denatured. Suitable plots permit the “melting point” of the protein to be assigned. Twenty proteins have been studied with emphasis on egg albumin. The transition temperature of egg albumin is independent of protein concentration, of pH in the neutral zone, is moderately dependent on the rate of heating, increases with increasing NaCl concentration, varies inversely with the guanidine hydrochloride concentration. There is more than a 35 °C spread in the melting temperatures of the various proteins and no apparent relation exists between the melting temperature of a protein and structural features of the protein.