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1.
本实验采用串脉冲刺激兔隔神经法复制了家兔膈肌疲劳模型。测定隔肌张力(Tdi)、跨膈压(Pdi)及其频率特性(Tdi-F、Pdi-F)、呼吸流速(V)、肺阻力(RL)、膈肌肌电图(EMGdi等作为评价膈肌收缩力量的指标。结果发现:经串脉冲刺激后,Pdi-F曲线在30、50和100Hz时显著降低,Pdi、Tdi、V和跨肺压均显著下降。氨茶碱可增加隔肌收缩力,延缓膈肌疲劳过程。结果提示,用串脉冲刺激兔膈神经法建立的模型是一种灵敏、可靠和稳定的膈肌疲劳动物模型。  相似文献   

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电刺激家兔膈神经中枢端(SCPN)可引起动脉血压下降,此降压反应不能被剪断双侧颈迷走神经或静脉注射阿托品1mg/kg所阻断;但可以被静脉注射酚妥拉明2.0mg/kg或静脉注射心得安1.5mg/kg部分阻断。去除缓冲神经后,其降压反应更明显。降压反应后1min血浆血管紧张素Ⅱ水平降低(P<0.005),肾神经传出放电(RND)减少(P<0.01),上述结果表明,膈神经的感觉纤维参与血压调节。  相似文献   

3.
中缝核与阻塞性睡眠呼吸暂停关系的实验研究   总被引:3,自引:0,他引:3  
本实验在64只氨基甲酸乙酯麻醉、断双侧迷走神经、自主呼吸的健康家兔上进行,观察电、化学刺激中缝背核(NRD)、中缝大核(NRM)对颏舌肌和膈肌肌电、以及窒息增幅反应(AARA)的作用。结果如下:1.长串电脉冲刺激NRD,颏舌肌和膈肌肌电幅度明显升高,在刺激过程中呈持续性吸气相放电。长串电脉冲刺激NRM,颏舌肌和膈肌肌电幅度显著抑制,呼吸节律减弱或消失;2.于NRD微量注入谷氨酸钠,颏舌肌和膈肌肌电幅度升高,频率加快。在NRM微量注射谷氨酸钠,AARA降低。上述结果与电刺激NRD、NRM的效应基本一致;3.NRM内微量注入吗啡,颏舌肌和膈肌的AARA峰值被抑制,潜伏期延长,恢复期缩短。若注射吗啡后5min再微量注入纳络酮,则吗啡的抑制效应减弱。结果提示:中缝核和阿片肽类物质对颏舌肌有重要的调制作用,可能与阻塞性睡眠呼吸暂停的发生有关  相似文献   

4.
新克痛宁术后镇痛效果观察   总被引:4,自引:1,他引:3  
王兴业  王凤学 《蛇志》1999,11(1):19-20
目的了解眼镜蛇毒制剂新克痛宁对术后镇痛效果。方法对72例胫腓骨折病人,在连续硬膜外阻滞麻醉下行切开复位内固定术,术后随机分为4组(每组18例)向硬膜外腔注药:A组新克痛宁0.25IU/kg;B组新克痛宁0.125IU/kg加0.5%利多卡因液10ml;C组吗啡2mg;D组吗啡1mg加0.5%利多卡因液10ml。结果镇痛持续时间A、B组明显延长,A与B组分别为(412±28)min,与C、D组比较差异显著(P<0.05)。注药后30~120min,患肢足背皮肤温度,A、B组亦高于C、D组(P<0.05),且无不良反应。结论新克痛宁术后镇痛效果比吗啡好。  相似文献   

5.
目的:探讨使用外源性肺表面活性物质(PS)治疗能否减轻烟雾吸入所致肺组织损害。方法:Wistar大鼠随机分为5组:I组,正常对照;Ⅱ组,烟雾吸入;Ⅲ组,烟雾+PS+机械通气(MV);Ⅳ组,烟雾+盐水+MV;Ⅴ组,烟雾+MV,伤后5min经气管导管注入PS(100mg/kg)或等量盐水,MV4h,观察24h,检测动脉血气、肺水量、支气管肺泡灌洗液(BALF)中白细胞分类计数及乳酸脱氢酶(LDH)、血  相似文献   

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目的和方法:本工作旨在研究免迷走复合区(DVC)内TRH对奥迪氏括约肌(SO)肌电的调节作用及外周途径。结果:(1)DVC内注射TRH(0.8nmol,1μl)后,慢波电位(SW)频率不变,但锋电位频率(FSPSO)及幅度(ASPSO)、锋电位发生率(ISP)明显增加.(2)DVC内分别注射不同剂量TRH(0.13,0.25,0.50,0.80,1.30nmol,1μl)后,各剂量TRH均能引起FSPSO增加。随注射剂量的增加,SO反应强度和持续时间均增加,呈现明显的剂量反应关系。(3)DVC内注射TRH兴奋FSPSO的效应可被静脉注射阿托品(0.2mg/kg)或迷走神经切断完全阻断,但不能被静脉注射酚妥拉明(1.5mg/kg)、心得安(1.5mg/kg)或脊髓切断术所阻断。结论:DVC内TRH可能对SO肌电有重要的调节作用,这种作用是通过迷走神经及外周M受体介导。  相似文献   

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30只雌性SD大鼠分为五组,即A组(阴性对照组),B组(孕三烯酮阳性对照组1mg/kg),C组(米非司酮实验组,Cl12mg/kg,C26mg/kg,C33mg/kg)。用组织化学方法观察米非司酮对子宫内膜一氧化氮合成酶(NOS)、琥珀酸脱氢酶(SDH)、乳酸脱氢酶(LDH)、酸性磷酸酶(ACP)、硷性磷酸酶(ALP)活性和糖原含量的影响。实验结果显示:NOS,SDH和ALP活性较阴性对照组弱,LDH和ACP活性较阴性对照组强,糖原含量略低于阴性对照组。  相似文献   

8.
雄性SD大鼠33只,体重180—250g,随机分成四组。正常对照组6只;哌唑嗪组8只,于实验第1、2、3日上午用哌唑嗪灌胃(1mg/kg体重)共3次,第2日下午腹腔注射半乳糖胺(600mg/kg体重)1次,第4日上午处死动物,取肝脏及血清作有关检查;普萘洛尔组及N.S对照组分别用普萘洛尔(2mg/kg体重)及N.S(10ml/kg体重)代替哌唑嗪灌胃,处理程序同哌唑嗪组。结果表明:一、哌唑嗪能显著减轻肝脏病变及血清ALT的升高。二、哌唑嗪对肝损害后肝组织SDH、Mg2+-AT-Pase、ChE、ACP、CCo等酶活性的恢复有显著效果。三、哌唑嗪组LPO明显低于N.S对照组(P<0.01)而SOD活性明显高于N.S对照组(P<0.01)。普萘洛尔组各项指标同对照组比较均无显著差异(P>0.05)。提示:哌唑嗪对大鼠实验性肝损害有一定的保护作用。  相似文献   

9.
铝对大白鼠海马所致损害的实验研究   总被引:5,自引:0,他引:5  
为探讨铝对海马的损害,用30只健康大白鼠,体重200~300克,分为A组(正常对照)10只,B组(低铝组饲料中加500mg/kgAlCl3)10只,C组(高铝组饲料中加2500mg/kg/AlCl3)10只。分别饲养12个月后,分组断头取脑海马,按组织化学及酶组织化学常规做“铝定性”反应,琥珀酸脱氢酶(SDH)、乳酸脱氢酶(LDH)、硫胺素焦磷酸酶(TPPase)、镁激活三磷酸腺苷酶(Mg2+-ATPase)、胆碱酯酶(ChE)测定。按电镜常规做超微结构的观察。结果提示:C组,海马SDH、Mg2+-ATPase、ChE活性明显减弱(由强阳性()下降为阳性(+),铝反应增强(在海马的神经细胞内强阳性();同时海马神经元内线粒体嵴断裂、肿胀、空泡样变,神经纤维髓鞘变性(如不规则卷曲、松散)。说明铝对海马的功能与结构均有损害  相似文献   

10.
神经生长因子在6—OHDA化学性去交感神经中的保护作用   总被引:1,自引:0,他引:1  
本实验用6-OHDA造成成年小白鼠颌下腺化学性去交感神经,观察了神经生长因子对该神经的保护作用。6-OHDA处理后24小时腺体内去甲肾上腺素(NE)含量降至正常水平的2%以下。若在6-OHDA处理同时开始多次给予神经生长因子(NGF),则NE残留量明显提高。减小6-OHDA剂量到10mg/kg,NE残留量增加,同时NGF的作用亦较用6-OHDA15mg/kg时列为显著。若提前24小时给予NGF,尽  相似文献   

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It has now been over twenty years since a novel herpesviral genome was identified in Kaposi's sarcoma biopsies. Since then, the cumulative research effort by molecular biologists, virologists, clinicians, and epidemiologists alike has led to the extensive characterization of this tumor virus, Kaposi's sarcoma-associated herpesvirus(KSHV; also known as human herpesvirus 8(HHV-8)), and its associated diseases. Here we review the current knowledge of KSHV biology and pathogenesis, with a particular emphasis on new and exciting advances in the field of epigenetics. We also discuss the development and practicality of various cell culture and animal model systems to study KSHV replication and pathogenesis.  相似文献   

16.
Comprises species occurring mostly in subtidal habitats in tropical, subtropical and warm-temperate areas of the world. An analysis of the type species, V. spiralis (Sonder) Lamouroux ex J. Agardh, a species from Australia, establishes basic characters for distinguishing species in the genus. These characters are (1) branching patterns of thalli, (2) flat blades that may be spiralled on their axis, (3) width of the blade, (4) primary or secondary derivation of sterile and fertile branchlets and (5) position of sterile and fertile branchlets on the thalli. Application of the latter two characters provides an important basic method for separation of species into three major groups. Osmundaria , a genus known only in southern Australia, was studied in relation to Vidalia , and its separation from the Vidalia assemblage is not accepted. Species of Vidalia therefore are transferred to the older genus name, Osmundaria. Two new species, Osmundaria papenfussii and Osmundaria oliveae are described from Natal. Confusion in the usage of the epithet, Vidalia fimbriala Brown ex Turner has been clarified, and Vidalia gregaria Falkenberg, described as an epiphyte on Osmundaria pro/ifera Lamouroux, is revealed to be young branches of the host, Osmundaria prolifera.  相似文献   

17.
Fifteen chromosome counts of six Artemisia taxa and one species of each of the genera Brachanthemum, Hippolytia, Kaschgaria, Lepidolopsis and Turaniphytum are reported from Kazakhstan. Three of them are new reports, two are not consistent with previous counts and the remainder are confirmations of very scarce (one to four) earlier records. All the populations studied have the same basic chromosome number, x = 9, with ploidy levels ranging from 2x to 6x. Some correlations between ploidy level, morphological characters and distribution are noted.  相似文献   

18.
肝癌中HBV和HCV基因和抗原的分布及意义   总被引:1,自引:0,他引:1  
采用原位分子杂交方法检测HCV RNA及HBV X基因;采用免疫组织化学方法研究HCV核心抗原,非结构区C33c抗原及HBxAg在肝细胞肝癌中的定位及分布.结果表明(1)HCV RNA、HBV X基因在肝细胞肝癌组织检出率分别为40%(55/136)和82%(112/136).HCV RNA定位于癌细胞的胞浆内,阳性细胞呈散在、灶状及弥漫分布三种形式;HBV X基因在肝癌细胞中的分布呈胞浆型、核型及核浆型,阳性细胞也呈上述三种分布形式;(2)HCV C33c抗原、核心抗原在肝细胞肝癌中的阳性率为81%(133/164)及86%(141/164).C33c抗原定位于癌细胞及肝细胞的胞浆内;核心抗原既定位于癌细胞核中,又可定位于胞浆中.C33c抗原阳性细胞以灶状分布为主;而核心抗原阳性细  相似文献   

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For a plant selection model with frequency-independent viabilities, fertilities and selfing rates, it is shown that apart from global fixation, for certain parameter combinations a protected polymorphism and facultative fixation (either allele may become fixed according to initial frequencies) may both occur. Facultative fixation requires different selling rates for the dominant and recessive type. Protection of the polymorphism requires resource allocation for male and female function. In this connection the problem of purely genetically caused population extinction is discussed.
For general frequency dependence and regular segregation, the chances for establishment of a completely recessive gene are compared to those of a completely dominant gene. It is proven that the process of establishment of the recessive gene, despite a fitness advantage, may be considerably endangered by drift effects if random mating prevails. The recessive gene may reach the same effectivity in establishment as a dominant gene, only if the recessive homozygote mates exclusively with its own type during the period of establishment.  相似文献   

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