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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(ASPSO)、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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兔迷走复合区内微量注射TRH对奥迪氏括约肌肌电的影响及?… 总被引:1,自引:0,他引:1
目的和方法:本工作旨在研究兔迷走复合区(DVC)内TRH对奥迪氏括约肌电的调节作用及外周途径。结果:(1)DVC内注射TRH(0.8nmol,μl)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 相似文献
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中缝隐核投射至中脑导水管周围灰质腹侧部的递质分析 总被引:3,自引:0,他引:3
实验在戊巴比妥钠麻醉大鼠上进行。双侧中脑导水管周围灰质腹侧部(vPAG)微量注射1μg/μl肾上腺素(每侧0.1μl),刺激中缝隐核(NRO)引起的降压反应明显增强,但该效应可被vPAG预先注射心得安所阻断,而注射酚妥拉明对上述效应无明显影响;vPAG内单独微量注射1μg/μl心得安(每侧0.1μl),可部分阻断NRO降压反应,而注射1μg/μl酚妥拉明(每侧0.1μl)无明显影响;双侧vPAG微量注射10μg/μl吗啡或0.1mol/L5-HT(每侧0.1μl),基础血压无明显变化,NKO的降压反应幅度减小(P<0.05)。提示,NKO对vPAG的兴奋作用的可能递质为肾上腺素,通过β受体介导;吗啡或5-HT则可减弱NRO对vPAG的兴奋性投射作用。 相似文献
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电刺激下丘脑穹窿周围区(PFA)的下丘脑背内侧核(DMH),下丘脑腹内侧核(VMH)与下丘脑外侧区(LHA)均可引起心肌P0_2下降与血压升高,而以DMH所致的心肌P0,下降最明显(P<0.01)。心得安可取消电刺激LHA所致的心肌PO_2下降,部分取消电刺激VMH引起的心肌PO_2下降,而不改变电刺激DMH所致的心肌PO_2下降(P>0.05)。DMH、VMH微量注射谷氨酸钠(0.1mol/L0.5μl)均可诱发升压反应和ECG-ST压低,而LHA微量注射谷氨酸却导致降压反应,对ECG-ST无明显影响。上述结果提示DMH为PFA各区诱发心肌缺血缺氧的主要核团。兴奋DMH、VMH所致的心血管效应主要由胞体兴奋诱发,而电刺激LHA所致的升压反应主要为兴奋过路纤维引起,该区胞体兴奋主要导致降压反应。 相似文献
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大鼠中缝隐核增强dPAG诱导的vPAG的c-Fos表达及对vPAG神经元放电的影响 总被引:3,自引:0,他引:3
本实验通过Pos免疫细胞化学、电生理及微量注射法对中缝隐核(NRO)的交感抑制作用的相关途径进行探讨。实验在成巴比妥钠或α-氯醛糖和氨基甲酸乙脂麻醉的Sprague-Dawley(SD)大鼠上进行。同时予以NRO,中脑导水管周围灰质背侧部(dPAG)方波脉冲串刺激,诱导中脑和延髓的c-Fos表达。刺激NRO过程中,基础血压升高(P<0.05),刺激dPAG引起的防御性升压反应则减少(P<0.01);中脑导水管周围灰质腹侧部(vPAG)、巨细胞旁外侧核(PGL)的Fos样免疫阳性反应(FLI)细胞计数分别为66.5±8.3和10.8±1.5(刺激NRO+dPAG组),较单独刺激dPAG组明显增加,P值分别小于0.01和0.001;单或双脉冲刺激中缝隐核在vPAG可以记录到相关单位,其中84%为兴奋单位,抑制单位占16%。双侧vPAG内微量注射利多卡因(每侧2μg/0.1μl),基础血压无明显变化,而刺激NRO引起的降压反应幅度减小(P<0.01),提示,延髓腹外侧区(VLM)、NRO存在不同功能分化的神经元;NRO可能有向vPAG的兴奋性投射,此投射可加强NRO的交感抑制效应。 相似文献
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本工作观察麻醉兔用氟哌啶醇阻断肾多巴胺受体对血量扩张(VE)和脑室高张盐溶液注射(ICHNa)引起促钠排泄反应的影响。在VE实验中。对照组与氟哌啶醇组排销量增加峰值分别为65.6±15.0与19.0±5.5μmol/min(P<0.02);在ICHNa实验中,对照组与氟哌啶醇组排钠量增加峰值分别为28.9±4.6与29.0±5.8μmol/min(P>0.05),在肾多巴胺受体完好兔实验中,VE+ICHNag;起的促钠排泄大于VE(P<0.01)或ICHNa(P<0.01)引起的反应。肾多巴胺受体阻断也可显著减弱VE+ICHNa引起促钠排泄反应。结果表明:肾多巴胺受体阻断显著减弱VE以及VE+ICHNa引起促钠排泄,对ICHNa的反应无效;在正常兔VE+ICHNa引起促钠排泄显著大于各单一刺激的反应。 相似文献
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孤啡肽在大鼠脑内对抗吗啡镇痛 总被引:8,自引:0,他引:8
脑内全新的阿片受体样受体(1994)及其内源性配体孤啡肽(1995)的发现形成了中枢神经系统阿片/抗阿片相互关系的研究领域中一个新的推动力。基于它们与阿片家族的高同源性及在脑内痛觉整合相关区域的丰富表达,本实验观察了OFQ在大鼠脑内对吗啡镇痛作用的影响。结果表明:(1)OFQ可以对抗脑室注射生理盐水引起的镇痛,后者可能是一种由内源性阿片系统介导的应激镇痛。(2)脑室注射OFQ在很大的剂量范围(40 相似文献
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本文分析了中枢注射PEA抑制胃酸分泌效应的脑内过程。雄性Wistar大鼠,摘除双侧肾上腺,用37℃的生理盐水通过恒流泵进行连续胃液流。第三脑室给药,观察其对五肽促胃液素(160μg/kg,s.c.)诱导的胃酸分泌的影响。结果如下:(1)预先脑室注射抗CRF血清(2.5μl,1:20000)可阻断1OμgPEA的中枢抑酸效应;(2)分别脑室给予CRF(1.0和2.0μg)和β-内啡肽(0.94和1.25μg)均明显抑制胃酸分泌;(3)预先注射纳洛酮(5.0μg,i,c.v,)可取消CRF(1.0μg)的中枢抑酸效应,而预先注射抗CRF血清(2.5μl)对β-内啡肽(0.94μg)的中枢抑酸效应无明显影响。结果提示:PEA可能首先引起CRF释放,后者再刺激内源性阿片肽释放,从而导致迷走介导的胃酸分泌抑制效应。 相似文献
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中缝大核在刺激视上核镇痛中的作用 总被引:1,自引:0,他引:1
运用核团灌流液的放免测定和高压液相色谱法以及核团内注射拮抗剂,观察了化学刺激下丘脑视上核(SON)对中缝大核(NRM)灌流液内催产素(OT)、精氨酸加压素(AVP)和5-羟色胺(5-HT)含量的影响以及NRM内注射AVP、5-HT或OT受体拮抗剂对痛阈(PT)的影响。结果表明:SON内注射L-谷氨酸(L-Glu)10μg后动物痛阈明显升高,NRM灌流液中OT和5-HT的含量明显高于对照组水平,AVP的含量仅有一过性增加。NRM内注射oT或5-HT拮抗剂可逆转化学刺激SON引起的镇痛作用;而AVP的V_(1/2)受体拮抗剂也轻度抑制这种镇痛作用,但V_1拮抗剂对此作用无影响。以上结果提示:在刺激SON镇痛中,OT起着重要作用,L-Glu刺激SON的OT细胞释放OT,作用于NRM细胞的OT受体和V_2受体而产生镇痛作用,5-HT在此过程中也发挥重要作用。 相似文献
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甘肃省啮齿动物区系及地理区划的研究 总被引:10,自引:1,他引:9
甘肃啮齿动物有87种(含7亚种),隶2目9科41属。可将甘肃划分6个省:1.陇东高原省,有28种(含l亚种),2.中部黄土高原省,有30种;3.河西走廊省,有36种,三趾心颅跳鼠和短耳沙鼠为本省特有种;4.祁连山地省,有29种,高原高山鼠和银白高山鼠为本省特有种;5.甘南高原草原省,有34种,棕背鼾和普通田鼠为本省特有种,6.陇南山地省,有34种,豪猪和巢鼠为本省特有种。 相似文献
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人工饲养条件下高原鼠兔生长和发育的初步研究 总被引:10,自引:7,他引:3
本文研究了人工饲养条件下高原鼠兔的生长发育情况,并和其他种鼠兔的生长作了比较。室内高原鼠兔比野外的生长快,人工饲养的阿富汗鼠兔和北美鼠兔生长期短,成熟早。 相似文献
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应用阴茎骨形态指标划分黑腹绒鼠年龄的研究 总被引:1,自引:0,他引:1
用雄性阴茎骨近支基底高作频数分配将黑腹绒鼠指名亚种划分为5个年龄组,对各年龄组的体长、阴茎骨近支长和阴茎骨近支基底宽作t检验和F检验均有显著差异或极显著差异.表明以阴茎骨近支基底高划分黑腹绒鼠年龄组是可行的。 相似文献
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Acta Botanica Yunnanica 《Plant Diversity》1981,3(1):1-3
The Yunnan University, Kunming Institute of Botany, Academia Sinica, on December 5, 1980, 1ost its staff member through 30 years and more,the Senior Professor of Plant Ecology and Geo- botany,Head of Geobotanical Laboratory, (Yun- nan University),President the Yunnan Botanical Society, Editor of Acta Botanica Yunnanica, etc 相似文献
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Intraspecific variation in seed size is common in wild plant populations and has important consequences for the reproductive success of individual plants. Multiple, often conflicting evolutionary forces mediated by biotic as well as abiotic agents may maintain such a variation. In this paper we assessed seed size variation in a population of the threatened, commercially important palm Euterpe edulis in southeast Brazil. We investigated (i) how this variation affects the probability of attack by vertebrate and invertebrate post-dispersal seed predators, and (ii) if seed size influences the outcome of seeds damaged by beetles in terms of seed germination and early survival of seedlings. Euterpe edulis seeds varied in diameter from 8.3 to 14.1 mm. Neither insects nor rodents selected the seeds they preyed upon based on seed size. Seed germination and total, shoot and root biomasses of one-year seedlings were significantly and positively affected by seed size. Root biomass and seedling survival were negatively affected by seed damage caused by a scolytid beetle (Coccotrypes palmarum) whose adults bore into seeds to consume part of the endosperm, but do not oviposit on them. Seed size had a marginally significant effect on seedling survival. Therefore, if any advantage is accrued by E. edulis individuals producing large seeds, this is because of greater seed germination success and seedling vigor. If this is so, even a relatively narrow range of variation in seed size as observed in the E. edulis population studied may translate into differential success of individual plants. 相似文献
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Heterostylous self-incompatible plant species are particularly sensitive to habitat fragmentation and to disruption of pollination processes because of the need of intermorph cross-pollination for producing seeds. Heterostyly is characterized by sexual polymorphism through the occurrence of two (distyly) or three (tristyly) morph types that differ in floral traits (style length and anther position). We examined whether the long-styled (pin) and short-styled (thrum) morph types show differences in reproductive components and responses to habitat fragmentation in the distylous, self-incompatible perennial herb Primula veris. We documented reproductive components for pin and thrum individuals and their relationships with population size, plant density and morph ratio (pin frequency), in nine populations from Flanders (northern Belgium) located in fragmented habitats of the intensively used agricultural landscape. Seed abortion increased in small populations as a result of inbreeding depression. Fruit set increased with plant density. Seed set was positively related to pin proportion. Seed set was higher for pin than thrum in small populations, but lower in large populations. Two hypotheses can be considered to explain these morph-specific differences: a pollen transfer asymmetry, and a reproductive advantage for the partially self-compatible pin morph. Morph types appear to respond differently to habitat fragmentation constraints. A floral morph type showing partial self-compatibility may be favored in populations under pollination failure, because it can increase reproductive success and mating opportunities through intramorph crosses. 相似文献
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We assessed the effects of both biotic processes and abiotic factors on the community composition of vascular plant species and invertebrates at a site in northern Norway. Plant species were assigned to functional (woody versus herbaceous) and biogeographic (boreal versus alpine) groups. Invertebrate species were classified as either herbivore or predator. When species interactions and effects of the abiotic environment were partitioned, boreal species appeared to influence the distribution of alpine species and woody species the distribution of herbaceous species. Analysis of partial correlations indicated that facilitation was the dominant mode of interaction between the two pairs of plant groups. Among abiotic factors, the thermal environment probably influenced all components of the plant and invertebrate communities, except for predatory invertebrates, and wind appeared important in determining the composition of woody and alpine components of the plant community but not the herbaceous component. The composition of the boreal component of the plant community apparently influenced the composition of all invertebrate communities, except for predatory invertebrates. The composition of the woody component of the plant community influenced the composition of both herbivore and predator communities. The alpine plant-community composition influenced predatory invertebrate community composition. Woody plant community composition influenced the composition of both herbivore and predator communities. Our analytic approach, based on two kinds of structural equation models (d-separation and path analysis), provides a useful method for identifying the biotic as well as abiotic factors that influence community structure. 相似文献
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新生大鼠脊髓交感节前神经元的单胺能受体 总被引:1,自引:0,他引:1
应用新生大鼠离体脊髓薄片的细胞内记录,观察了5-羟色胺(5-HT)、去甲肾上腺素(NA)及肾上腺素(AD)对交感节前神经元(SPN)膜电位的作用,以期阐明三种单胺受体是共存于同一细胞,还是分别存在于不同细胞?实验结果显示:(1)5-HT,NA及AD分别使57.1%(16/28),60%(15/25)及52.4%(11/21)的SPN出现了去极化反应;(2)根据SPN对三种单胺的反应,可将60%(1 相似文献
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Amaya Leunda Bernadette Van Vaerenbergh Aline Baldo Stefan Roels Philippe Herman 《朊病毒》2013,7(5):420-424
Shadoo (Sho) is a brain glycoprotein with similarities to the unstructured region of PrPC. Frameshift alleles of the Sho gene, Sprn, are reported in variant Creutzfeldt-Jakob disease (vCJD) patients while Sprn mRNA knockdown in PrP-null (Prnp0/0) embryos produces lethality, advancing Sho as the hypothetical PrP-like “pi” protein. Also, Sho levels are reduced as misfolded PrP accumulates during prion infections. To penetrate these issues we created Sprn null alleles (Daude et al., Proc. Natl. Acad. Sci USA 2012; 109(23): 9035–40). Results from the challenge of Sprn null and TgSprn transgenic mice with rodent-adapted prions coalesce to define downregulation of Sho as a “tracer” for the formation of misfolded PrP. However, classical BSE and rodent-adapted BSE isolates may behave differently, as they do for other facets of the pathogenic process, and this intriguing variation warrants closer scrutiny. With regards to physiological function, double knockout mice (Sprn0/0/Prnp0/0) mice survived to over 600 d of age. This suggests that Sho is not pi, or, given the accumulating data for many activities for PrPC, that the pi hypothesis invoking a discrete signaling pathway to maintain neuronal viability is no longer tenable. 相似文献