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研究替来他明-唑拉西泮合剂对大鼠大脑皮质突触体钙离子浓度的影响,探讨突触体钙离子浓度变化与替来他明-唑拉西泮合剂麻醉的关系.密度梯度离心法制备SD大鼠大脑突触体悬液,分别加入高、中、低浓度的替来他明-唑拉西泮合剂,1mol/L KCl诱导作为对照,采用荧光分光光度法测定突触体内钙离子浓度.结果表明,加入替来他明-唑拉西泮合剂后,突触体内钙离子浓度升高,与对照组比较差异极显著(P＜0.01)；随着药物浓度的增加,突触体内钙离子浓度逐渐升高；替来他明-唑拉西泮合剂麻醉对大鼠大脑皮质突触体钙离子浓度的影响存在浓度依赖性.结果提示,替来他明-唑拉西泮合剂引起大鼠脑神经突触前钙离子内流使突触体内钙离子浓度升高,促使突触囊泡释放抑制性神经递质可能是其产生全身麻醉作用的机理之一. 相似文献
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《动物营养学报》2016,(2)
神经肽Y(NPY)是一种广泛存在于中枢和外周并维持内环境稳态的神经递质,其在机体摄食调控中起着主要作用。NPY神经元主要位于下丘脑弓状核(ARC),由其发出的纤维投射到达下丘脑室旁核(PVN)、腹内侧核(VMN)、外侧区(LHA)、背内侧核(DMN)等核团,通过NPY神经纤维与对应的受体形成突触,从而发挥促摄食调控作用。NPY受体是Gi/Go-蛋白偶联受体,有Y1~Y8 8个亚型受体,其中Y1受体在下丘脑能量代谢调控中发挥着主导作用。本文对NPY的结构以及ARC、PVN、VMN、LHA、DMN核团中NPY相关的摄食调控作用及其分子机制进行了阐述,旨在为相关研究提供基础资料。 相似文献
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ADP-核糖基化因子(Arf)属于小GTP酶的Ras超家族，与其他Ras相关的GTP结合蛋白一样，Arf蛋白在其活性GTP结合和非活性GDP结合构象之间循环。在酵母中其参与高尔基体和核内体的结构并发挥功能。在哺乳动物中Arf家族共包含了六个成员，基于大小和氨基酸序列同一性，这六种Arf蛋白可分为三类，Ⅰ类包括Arf1、Arf2和Arf3,Ⅱ类包括Arf4和Arf5,Ⅲ类包括Arf6。Arf蛋白在生物体内普遍表达，通过膜蛋白、细胞骨架调节因子的膜募集等协调细胞中的囊泡运输。同时，Arf蛋白还参与脂质信号传导和脂质代谢调节脂质介导的非囊泡运输。因此，Arf蛋白在有丝分裂、减数分裂、肌动蛋白细胞骨架、纤毛运输中均发挥重要功能。文章阐述了Arf蛋白家族成员在哺乳动物中的作用机制与功能，并对其未来研究进行了展望。 相似文献
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外泌体是由细胞产生并胞吐到胞外的纳米级颗粒，能够传递蛋白质、脂质和核酸等生物活性大分子，在细胞间信息传递中起着重要作用。近年来越来越多研究表明，外泌体在各感染性疾病中有传播感染物质的作用，也有诱导免疫反应和治疗作用。本文就外泌体在病原感染疾病中的作用进行综述，为后续进一步研究提供依据。 相似文献
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昆虫气味受体(Odorant receptors, Or)基因家族的分子演变与其对环境的生态适应性密切相关,在昆虫的生存和种族繁衍及躲避敌害中起着重要作用。Or基因展现出多种进化模式,有基因结构的变化、染色体位置的变化和复制变化,通过这些变化获得或失去某种功能,以适应生态环境变化。昆虫气味受体的拓扑学证明,它是与典型的G-蛋白耦联受体(哺乳类气味受体)反向的跨膜分布,通过特殊的离子门控通道和环核苷酸激活的非选择性离子通道,将气味分子信号传递到嗅觉感受器内嗅觉神经元,从而对气味作出简单、快速而有效的反应。 相似文献
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使用常规细胞内记录技术，对离体灌流的牛蛙椎旁神经节Ｂ细胞的电生理学特性和胆碱能突触传递进行了观察。所测得的电生理学指标与以往报道在体神经节的资料基本相符；刺激节前纤维引起的突触反应，如动作电位，快兴奋性突触后电位和慢兴奋性突触后电位可稳定地观察和记录到，在灌流液中加入某种药物或化学物质，通过对Ｂ细胞电生理学特性和突触传递的影响，可探讨分析其作用环节和机理，牛蛙椎旁神经节标本解剖结构的相对简单，生理 相似文献
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本研究旨在筛选牛体外受精胚胎早期发育差异表达基因,并进行差异表达分析。选取牛卵母细胞、体外受精8细胞期和囊胚期胚胎为试验材料,进行mRNA差异表达研究。初步克隆出4个牛卵母细胞和早期胚胎发育不同阶段差异表达的基因,同源性分析显示,它们分别与高移动样蛋白盒结构域4基因(HMGXB4)、热休克蛋白40亚家族C成员8基因(Dnajc8)、突触膜胞吐调节2基因(RI MS2)和核糖体蛋白L31基因(RPL31)高度同源。RT-PCR检测验证,HMGXB4、Dnajc8、RI MS2和RPL31在牛卵母细胞和早期胚胎发育过程中mRNA表达量存在时间性差异,可能与其参与不同的生理活动有关。 相似文献
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Meschan EM Peham C Schobesberger H Licka TF 《Veterinary journal (London, England : 1997)》2007,173(3):578-584
As there is no statistical evidence that saddle fit influences the load exerted on a horse's back, this study was performed to assess the hypothesis that the width of the tree significantly alters the pressure distribution on the back beneath the saddle. Nineteen sound horses were ridden at walk and trot on a treadmill with three saddles differing only in tree width. Kinetic data were recorded by a sensor mat. A minimum of 14 motion cycles were used in each trial. The saddles were classified into four groups depending on fit. For each horse, the saddle with the lowest overall force (LOF) was determined. Saddles were classified as "too-narrow" if they were one size (2 cm) narrower than the LOF saddle, and "too-wide" if they were one size (2 cm) wider than the LOF saddle. Saddles two sizes wider than LOF saddles were classified as "very-wide". In the group of narrow saddles, the pressure in the caudal third (walk 0.63 N/cm(2)+/-0.10; trot 1.08 N/cm(2)+/-0.26) was significantly higher compared to the LOF saddles (walk 0.50 N/cm(2)+/-0.09; trot 0.86 N/cm(2)+/-0.28). In the middle transversal third, the pressure of the wide saddles (walk 0.73 N/cm(2)+/-0.06; trot 1.52 N/cm(2)+/-0.19) and very-wide saddles (walk 0.77 N/cm(2)+/-0.06; trot 1.57 N/cm(2)+/-0.19) was significantly higher compared to LOF saddles (walk 0.65 N/cm(2)+/-0.10/ 0.63 N/cm(2)+/-0.11; trot 1.33 N/cm(2)+/-0.22/1.27 N/cm(2)+/-0.20). This study demonstrates that the load under poorly fitting saddles is distributed over a smaller area than under properly fitting saddles, leading to potentially harmful pressures peaks. 相似文献
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M. Masko M. Domino K. Skierbiszewska Ł. Zdrojkowski T. Jasinski Z. Gajewski 《Equine Veterinary Education》2020,32(12):654-663
Complications in late gestation are challenging problems for the equine clinician and are causes of considerable distress to owners. Health problems in a pregnant mare in each stage of gestation can adversely affect the pregnancy. It is important to obtain a thorough history and perform a detailed and systematic examination of the pregnant mare so that the mare may be classified as normal or high-risk. However, even after a thorough examination, practitioners may face problems with the interpretation and assessment of risk. Normal mares should foal in the stable or pasture. Mares classified as having a high-risk pregnancy need to be monitored precisely for signs of oncoming foaling with attendance of trained personnel when labour begins. A valuable method for monitoring of the high-risk mare is assessing fetoplacental well-being. Fetoplacental well-being is most accurately assessed with ultrasonography as well as several available hormone profiles. We are proposing our scoring system of the mare's health, which may be useful in the assessment of risk during pregnancy and help clinicians to decide whether sending the mare to the clinic is reasonable or unnecessary. 相似文献
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为了找出支配鸡胆囊交感节后神经元的分布规律,选用体重1.5 kg～2.5 kg的成年母鸡6只,将CT-HRP溶液注入胆囊壁,动物存活3 d～4 d后,经左心室灌流固定,取内脏神经节、肾上腺神经节以及双侧胸、腰和荐段交感干神经节,制成50 μm的连续冰冻切片,TMB法呈色反应,置明视野显微镜下观片统计.结果发现,支配鸡胆囊的交感传出神经元胞体位于内脏神经节(占41.1%)、肾上腺神经节(占40.5%)和T2～T7交感干神经节(占18.4%),在交感干神经节中标记细胞的峰值位于T5、T6交感干神经节.所有的标记细胞以位于右侧的占优势. 相似文献
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Webbon P 《Equine veterinary journal》2012,44(1):8-12
The understanding and application of genetics have grown extremely quickly since it has become possible to sequence the whole genome of an organism. The human genome sequence was completed in 2001 and that of the horse in 2007. The significance of this is that it makes it more feasible to explain how both genetically simple and complex traits are transmitted from one generation to the next and, therefore, to make informed breeding decisions, modify how horses are managed and trained to minimise the risk of disease and injury, and improve methods of prevention, diagnosis and treatment of many conditions. The science of genetics/genomics will continue to grow internationally, limited only by the funds available. The application of the science to man, horses and other species raises very complex moral and commercial issues. Thoroughbred breeders are perceived by some as resistant to change, but their apparent intransigence is often based on a genuine concern for the integrity of the breed. By taking control of the application of the advances in genetics, the Thoroughbred industry potentially has the opportunity to improve both the health and performance of Thoroughbreds. If, however, the science is applied in an uncoordinated manner, driven by commercial interests with no underlying concern for the horses themselves, there is a very real risk that breeders, the Thoroughbred breed and individual horses will all suffer as a consequence. 相似文献
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犊牛腹泻与肠道菌群的变化 总被引：1，自引：0，他引：1
本文检测腹泻犊牛的直肠内8种主要正常菌群的变化,并与健康犊牛进行对比。结果发现,犊牛腹泻时,大肠杆菌、双岐杆菌和乳杆菌变化较大,而其它菌群变化较小。腹泻或将腹泻时,大肠杆菌数增加,双岐杆菌和乳杆菌数下降。腹泻康复或即将康复时,大肠杆菌减少,双岐杆菌、乳杆菌数增加。 相似文献
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试验选择陕北白绒山羊繁育中心羊场的成年健康母羊（怀孕前期）16只,育成母羊13只,育成公羊13只,空腹称重。测定每只羊1d的采食量,计算其摄入的营养成分含量,并与原苏联绒用山羊饲养标准比较,进行饲养水平评价。结果显示,与饲养标准比较,陕北白绒山羊繁育中心羊场的育成母羊代谢能高2．68MJ,粗蛋白低59．29g,钙低3．00g,磷低1．52g;育成公羊代谢能高3．47MJ,粗蛋白低81．92g,钙低4．42g,磷低2．62g;成年母羊代谢能高2．51MJ,粗蛋白低91．33g,钙低3．09g,磷低1．93g。结合羊的体况综合评价饲养水平基本合理,但尚需要按饲养标准增加粗蛋白、钙、磷等营养物质的供给量。 相似文献
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Evidence for the non-involvement of the uterus in the lifespan of the corpus luteum in the cyclic dog 总被引：1，自引：0，他引：1
Progesterone levels in peripheral blood of dogs were analysed during the cycle in which hysterectomy (n = 5) or sham surgery (n = 3) was performed as well as during the cycle of dogs (n = 5) hysterectomized at least one year prior to this study; the data were compared with the findings in control dogs (n = 3). The averages of the duration of the luteal period observed in the three experimental groups were not significantly different from those of control dogs. Immediately after surgery, the progesterone level decreased from 25 to 50% of the presurgical level, but returned to presurgical level in about four days. Prolactin levels were elevated for about 30 h after surgery. Nevertheless, the averages of the mean prolactin levels for each animal during the luteal period of the experimental groups were not significantly different from those of control dogs. It is concluded that in the dog, the uterus is not involved in the lifespan of the cyclic corpus luteum. 相似文献