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1.
本文观测了Acetyl-DL-leucine对猫单侧前庭神经切断后前庭代偿的影响。结果显示;AL加快术后猎在转动横梁测试中运动平衡能力的恢复,但抑制去传入前庭外侧核神经元静息自发放电频率的恢复。AL促进放电活动与头部左右动体位相关的神经元数量和比例的恢复,从术后的第1周的10%,逐渐提高到术后第3周的60%。第5周的75%。  相似文献   

2.
山东10种植物的核型分析   总被引:5,自引:1,他引:5  
杨德奎  周俊英   《广西植物》1999,19(4):349-354+395
对山东10 种植物进行了核型分析。茴茴蒜( Ranunculuschinensis Bge-) 染色体数目2n =16 , 核型公式K(2n) = 2x = 16 = 2 M + 2m + 2sm + 10st, “3A”类型; 五脉地椒( Thymusquinquecostatus Celak-) 染色体数目2n= 26 , 核型公式K (2n) = 2x= 26 = 8 M + 18m , “1A”类型; 蛇床( Cnidium monnieri(L-) Cuss-) 染色体数目2n= 20 , 核型公式K (2n) = 2x= 20 = 2M+ 16m + 2sm , “2B”类型; 波斯菊( Cosmos bipinnatus Cav-) 染色体数目2n = 24 , 核型公式K(2n) = 2x = 24 = 16m + 2m (sat) + 6sm , “2A”类型; 白车轴草( Trifolium repens L-) 染色体数目2n= 32 , 核型公式K (2n) = 4x = 32 = 32m , “1A”类型; 铁苋菜( Acalypha australis L-)染色体数目2n = 32 , 核型公式K (2n) = 2x= 32 = 32m , “1B”类型; 地构叶( Speranskia t?  相似文献   

3.
L-NNA及NO供体对延髓腹外侧头端区神经元自发放电的影响   总被引:3,自引:1,他引:2  
在麻醉大鼠观察了静注NO合成酶抑制剂N-硝基左旋精氨酸(L-NNA)和NO供体──硝普钠(SNP)和SIN-I对血压、心率和延髓腹外侧头端区(RVLM)神经元自发放电活动的影响,旨在探讨L-arg:NO通路对动脉血压调节的中枢作用部位。所得结果如下:(1)静注L-NNA后,平均动脉压(MAP)升高,心率(HR)加快,11个RVLM神经元自发放电频率增加。这些变化发生于给药后5min,持续时间达30min以上。(2)静注SNP后,MAP降低,HR加快,23个RVLM神经元自发放电频率降低,且有剂量依赖性。SNP作用发生快,持续时间短。为了排除脑缺血的影响,还特意向一侧颈动脉内注射相同剂量SNP,结果引起MAP轻度降低,而HR无明显改变,但RVLM神经元自发放电频率仍显著降低。(3)静注另一NO供体SIN-I后,MAP降低,11个RVLM神经元自发放电频率降低.与SNP的效应基本一致。以上结果提示,RVLM是L-arg:NO通路实现动脉血压调节的一个中枢作用部位。  相似文献   

4.
英加  陈佩度 《遗传学报》2000,27(6):506-510
对普通小麦(Triticum aestivum)-节节麦(Aegilops squarrosa)八倍体(2n=8x=56,AABBDDDD)与硬粒小麦(Triticum durum)-簇毛麦9Haynaldia villosa)六倍体(2n=6x=42,AABBVV)杂交后,将所得七倍体杂种(AABBDDV)进行连续自交,在F4代中利用C-分带鉴定出可能的簇毛麦6V二体附加系95-7和2V二体附加  相似文献   

5.
Wang XB  Hu SJ  Ju G 《生理学报》2000,52(4):339-342
实验采用离体脑片全细胞膜片箝记录方法,观察了细胞因子白介素-1β(IL-1β)和IL-2对大鼠离体脑片视上核神经元膜电位及自发放电的影响,以期探明免疫应答大鼠视上核神经元对细胞因子敏感性的变化。结果显示,用100U/ml IL-1β藻流脑片,正常对照的(n=15)和脂多糖(lipopolysacchyaride LPS)腹腔注射9d的大鼠视上核神经元(n=20)超极化,同时伴有自发放电频率的下降;  相似文献   

6.
英加  陈佩度 《武汉植物学研究》2000,18(4):261-265,T001
对2个八倍体C.S-Thinopyrum bessarabicum(AABBDDJJ,2n=8x=56)和Goshawk(GHK)-Thinopyrum elongatum(AABBDDEE,2n=8x=56)的根尖细胞染色体进行C-分带,从中分检出Th.bessarabicum和Th.elongatum的各自染色体进行核型分析,结果表明:Th.bessarabicum和Th.elongatum的  相似文献   

7.
吉林省产5种百合的核型研究   总被引:17,自引:0,他引:17  
报道了吉林省产5种百合科植物的染色体数目和核型:①毛百合Lilium dauricum Ker.-Gew1.2n=24=2m(2SAT)+2sm(2SAT)+8st(2SAT)+12t(2SAT);②有斑百合L.concolor Salisb.var.buschianum(Lodd.)Baker 2n=24=2m(2SAT)+4sm(4SAT)+6st(2SAT)+12t;③兰州百合L.david  相似文献   

8.
对青藏高原高山冰缘地区毛茛科3种特有植物的核型进行了分析。它们的核型公式(K)、染色体相对长度组成(C.R.L.)和核型不对称系数(As.K%)分别为:青藏金莲花Troliuspumilusvar.tanguticus:K(2n)=6m+8sm(2SAT)+2st,C.R.L.=4L+4M2+4M1+4S,As.K%=63.57,核型属2B型;甘青乌头Aconitumtanguticum为K(2n)=6m+10sm,C.R.L.=4L+8M1+4S,As.K%=62.54,2B型;单花翠雀花Delphiniumcandelabrumvar.monanthum为K(2n)=6m+8sm+2st,C.R.L.=4L+4M2+4M1+6S,As.K%=64.34,属3B型。经同相关近缘种核型资料比较,青藏金莲花核型不对称性和进化程度比金莲花T.chinensis低;甘青乌头的核型不对称性和进化程度在其近缘类群(乌头组Sect.Aconitum)已报道的种之内最低;单花翠雀花核型不对称性和进化水平比翠雀组(Sect.Delphinastrum)已报道的展毛翠雀花D.kamaoensevar.glabrescens、  相似文献   

9.
Chu XP  Li P  Xu NS 《生理学报》1998,50(5):483-489
在73张脑片上观察了γ-氨基丁酸(GABA)对106个延髓头端腹外侧区(RVLM)神经元单位放电的影响。外源性的GABA(0.1 ̄3.0mmol/L)抑制了106神经元中的84个神经元的电活动,这些抑制效应呈剂量-反应关系。GABA的抑制效应大部分可被GABAA受体选择性拮抗剂荷苞牡丹碱甲基碘化物(BMI)和Cl^-通道阻断剂印防己毒素(PTX)所阻断,而单独灌流BMI和PTX对RVLM神经元主要  相似文献   

10.
单侧前庭神经切断后猫运动方式的改变和补偿   总被引:1,自引:0,他引:1  
孙久荣 《生理学报》1997,49(1):18-24
本工作首次将一种运动分析系统,即视觉自动电视摄相信息处理系统(opticalautomaticTV-imageprocessor,E.L.I.T.Esystem)用于动物运动方式的定量分析,比较了猫一侧前庭神经切断前后在跨越转动横梁测试中运动方式的变化。结果如下:在横梁静止条件下,猫述后行走的初始身高明显下降,步距变短,步 频降低,呈缓慢的蹒中山步态,继而各参量逐渐增加,分别在术后45和70d恢复  相似文献   

11.
Of 62 patients given 2 gm. of streptomycin daily for an average of 110 days, 42 had complete loss of vestibular response to caloric stimulation. In the great majority of cases, response returned in varying degrees over a period of two years. The incidence of loss of response was higher among patients who weighed less than 125 pounds than among heavier patients, and it was higher among patients over 45 years of age than among those who were younger. Response returned earlier in the younger patients than in the older.Of 215 patients given 1 gm. of streptomycin for an average of 110 days, 18 had complete loss of vestibular response to stimulation. Sixteen regained response within a year, one in 17 months, and one was lost to study.  相似文献   

12.
超重对前庭系统及相关体系结构和功能的影响   总被引:2,自引:0,他引:2  
孙久荣 《动物学报》2001,47(3):343-346
超重环境中怀孕、出生或生存的动物返回正常环境后,行为活跃、站立姿势夸张、空中翻正及游泳和在转动横梁上行走的平衡能力下降,超重增加伸肌的力、改变耳石的形态和分布、降低毛细胞和前神经元对重力的敏感性、相应增加和减少某些神经递质(如云甲肾上腺素和5-HT)的合成和分泌,脑干内不同的核团构成特异性应答超重和减重刺激的神经网络。  相似文献   

13.
The lateral vestibular nucleus consists of multipolar isodendritic neurons of various sizes The distal segments of some dendrites display broad expansions packed with slender mitochondria and glycogen particles. These distinctive formations are interpreted as being growing tips of dendrites, and the suggestion is advanced that they are manifestations of architectonic plasticity in the mature central nervous system. Unlike large neurons elsewhere, the giant cells (Deiters) contain small Nissl bodies interconnected in a dense mesh-work. The Nissl substance is characterized by randomly arranged cisterns of the endoplasmic reticulum and by a high proportion of free ribosomes. Whether attached or free, ribosomes usually cluster in groups of four to six, and larger polysomal arrays are rare. Free ribosomal clusters also occur in the axon hillock and the initial segment. The neuronal perikarya contain distinctive inclusions consisting of a ball of neurofilaments enveloped by a complex honeycombed membrane. The failure of these fibrillary inclusions to stain with silver suggests that the putative argyrophilia of neurofilaments may reside in an inconstant matrix surrounding them. Giant cells of Deiters are in intimate contact with two kinds of cellular elements—astroglial processes and synaptic terminals. Oligodendroglial cells are only rarely satellites of giant cells; in contrast, they are frequently satellites of small and medium-sized cells.  相似文献   

14.
前庭代偿中猫的头部和颈部姿势的改变   总被引:1,自引:0,他引:1  
孙久荣 《动物学报》1997,43(2):163-169
首次用视觉自动摄像信息处理系统记录了猫一侧前庭神经切断后在跨越转动横梁时头和颈运动的姿势,主要分析了头和颈在矢状面和水平面上的转动角度和高度和变化,结果显示,正常猫在各种转速和转向条件下头和颈均始终保持因有的稳定的姿势;前庭神经损伤后,头和颈偏于上仰并向患侧扭曲,其改变的幅度和恢复时程可因转速不同而异,且发现头上仰的恢复早于头向患侧扭曲的恢复。  相似文献   

15.
The expression of the five muscarinic acetylcholine receptor (mAChR) subtypes (m1–m5) in the vestibular end-organs and in the primary afferent vestibular ganglia of the human and rat was studied using RT-PCR from the two tissue populations from both species. In the human, although all five mAChR subtypes were expressed in brain, only the m1, m2, and m5 mAChR subtypes were amplified from both the vestibular ganglia and the vestibular end-organs, while in the rat, all five mAChR subtypes were expressed. These data suggest that the efferent cholinergic axo-dendritic and axo-somatic synapses have a muscarinic component and that there are pharmacologic implications for patients with vestibular dysfunction.  相似文献   

16.
17.
罗萍  顾蕴辉 《生理学报》1992,44(1):31-38
实验用乌拉坦麻醉、箭毒化、人工呼吸的大鼠。将神经元胞体兴奋剂L-谷氨酸钠(Glu)微量注入顶核或前庭上核均引起血压下降;心率减慢。该顶核-和前庭上核-降压降心率反应均可被延髓头端腹外侧区内注射GABA受体阻断剂荷包牡丹碱阻断。顶核内注射普鲁卡因也能阻断Glu兴奋前庭上核的心血管反应。以上结果提示前庭-降压降心率反应可能通过顶核-延髓头端腹外侧区系统实现。静脉注射甲基阿托品也能衰减Glu兴奋顶核的心血管反应,显示迷走神经也参与前庭-顶核降压降心率反应。  相似文献   

18.
A study of four species of Erysiphaceae (Uncinula salicis, Podosphaera leucotricha, Erysiphe cichoracearum, and Microsphaera diffusa) revealed that the binucleate stages of the ascocarp are initiated in a similar manner to those of Diporotheca rhizophila Gordon & Shaw. The “appendages” developing on immature ascocarps are considered to be receptive hyphae. Appendages characteristic of mature ascocarps are produced much later. Lysis of certain centrum cells occurs, and asci are initiated from some of the remaining binucleate centrum cells. Resorption of centrum cells by the asci is supported by this investigation, corroborating Björling's earlier studies on Erysiphe graminis.  相似文献   

19.
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