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2.
大鼠隔—海马通路损伤对海马内递质含量及酶活力的影响   总被引:3,自引:0,他引:3  
汪家政  柳川 《生理学报》1990,42(3):289-294
单侧切断大鼠海马缴和部分穹窿可使海马部分去神经。损伤后7d,海马内胆碱能系统中乙酰胆碱(ACh)含量下降72.5%,胆碱乙酰基转移酶(ChAT)活力下降45.7%,胆碱酯酶活力下降52.2%,在单胺能系统中,去甲肾上腺素(NA)含量下降16.3%,多巴胺(DA)含量下降31.3%,5-羟色胺含量下降30.3%。在损伤过程中,海马内氨基酸含量没有改变。实验结果表明,海马缴和穹窿是脑内胆碱能和单胺能传入神经到达海马靶区的部分共同通路。  相似文献   
3.
坛紫菜原生质体的发育研究   总被引:11,自引:0,他引:11  
用2%的海螺酶和1%的纤维素酶混合,将坛紫菜叶状体的4种不同细胞类型即:营养细胞、根丝细胞、精子囊和果孢子囊,分别解离成原生质体,并研究了这些不同部位和不同生长时期。细胞的生长、发育途径。由根丝细胞分离的原生质体能长成新的叶状体;由早期中部营养细胞分离的原生质体,有70%长成新的叶状体,其余的发育成精子囊和果孢子囊。再生叶状体在室内培养,能正常成熟。由精子囊和果孢子囊分离的原生质体,即精子细胞和果孢子细胞不能再生叶状体。前者形成新的精子囊放散精子,后者形成新的果孢子囊,放散果孢子发育成丝状体。晚期紫菜与早期紫菜比较,再生叶状体的数量显著减少,而发育成精子囊和果孢子囊的数量则大大增多。  相似文献   
4.
Abstract.
  • 1 A case study is presented of the autumn migration of the brown planthopper, Nilaparvata lugens (Stål), in the area of Nanjing in the People's Republic of China. The study was made using a high frequency (8 mm wavelength) radar and a net suspended from a kytoon.
  • 2 The observations confirmed that long-distance return migrations occur in China in mid and late September, with N.lugens being carried on the prevailing north-easterly wind towards the autumn infestation and overwintering areas of the species.
  • 3 After mass take-off in the late afternoon or at dusk, the migrants flew for several hours during the evening, often in a dense layer which formed at heights between about 400 and 1000m above ground. These layers often had well-defined ceilings corresponding to an air temperature of about 16°C. The migration height was above the top of the surface temperature inversion, i.e. the migrants did not fly at the height of the warmest air.
  • 4 The dense layer concentrations overflying the radar were backtracked to source areas up to 240 km away in the north-east of Jiangsu Province. Planthoppers observed emigrating from the Nanjing area would reach areas in south Anhui Province or north Jiangxi Province if they flew for 12 h.
  • 5 There was a second period of mass take-off at dawn. Insect layers sometimes formed but did not last longer than 1–2h.
  • 6 The present results were strikingly different from those previously observed in the dry season in the Philippines, where migratory flight durations were largely confined to periods of about 30min at dusk and dawn.
  • 7 Our observations are discussed in relation to the equator-wards return migrations undertaken in autumn by other insect species, and the importance of these migrations for the maintenance of long-flying genotypes in the overwintering populations is considered.
  相似文献   
5.
洪敏  鲍涛 《生理学报》1991,43(5):494-498
给完整的及切除肾上腺的雌性 Wistar 大鼠分別注射地塞米松、去氧皮质酮或地塞米松加去氧皮质酮;冷酚法提取心房总 RNA,用α-~(32P)标记的大鼠心房肽 cDNA 探针与之杂交。完整大鼠接受地塞米松和切除肾上腺后接受地塞米松加去氧皮质酮的大鼠,心房肽基因转录产物增加2倍,其余组无显著变化。结果提示糖皮质激素可促进心房肽基因表达,但此作用依赖于盐皮质激素的同时存在,单纯盐皮质激素不能增强该基因的表达。  相似文献   
6.
包永德  朱辉 《生理学报》1996,48(6):587-589
爪蟾卵母细胞经注射鲫鱼视网总RNA后,可表达大量电压依赖性钾离子通道。在此基础上,我们进一步发现,一个特定序列的寡核苷酸能专一地抑制该通道的表达。由于我们设计与合成的该片段与果蝇、小鼠中已克隆的钾通道中编码N端的一个多肽的mRNA完全互补,因此推测:鲫鱼视网膜中的K这个区域与其它物种的K通道有高度同源性,这为克隆该基因和研究它的功能提供了重要资料。  相似文献   
7.
Stomatal conductance in improved Pima cotton cultivars (Gossypium barbadense) has been previously shown to be positively associated with heat resistance and yield potential. In the present study we determined the mode of inheritance of stomatal conductance in crosses of six G. barbadense parents varying in origin, degree of agronomic development and stomatal conductance. Parents included a primitive tropical cotton (B368), two obsolete cultivars (St Vincent V135, Pima 32), one modern commercial line (Pima S-6) and two elite genotypes of the Pima germplasm (P70, P73). These lines showed distinct differences in stomatal conductance, under greenhouse and field conditions. The primitive B368 had the lowest conductance, and the elite lines the highest. Generation means analysis was used to quantify genetic effects in the crosses P70 × St Vincent V135, Pima S-6 × B368, Pima S-6 × Pima 32, P73 × Pima 32 and P73 × Pima S-6. Best-fit models of the inheritance of stomatal conductance varied in complexity from a simple additive-dominance model in the cross P70 × St. Vincent V135 to models displaying digenic epistatic interactions in the remaining crosses. Significant additive mean effects for stomatal conductance were detected in all crosses. Dominance mean effects were significant in the crosses P73 × Pima 32 and P73 × Pima S-6. Broadsense heritability estimates of stomatal conductance were relatively low (0.16–0.44) in all crosses except Pima S-6 × B368 (0.74). Results also show that the mode of inheritance of stomatal conductance is multigenic, and may have maternal as well as nuclear components. Recouping higher stomatal conductance levels from genetically wider crosses appears feasible and could proceed at a moderate rate. Fixing higher levels of stomatal conductance in populations from crosses of elite germplasm may be more difficult because of the presence of dominant mean effects and digenic epistatic interactions.  相似文献   
8.
本文了剑角蝗科窝蝗属1新种:郑氏窝蝗Foveolatacris zhengi,sp.nov。,采自甘肃省南县宝瓶河牧场;并据此对属征作了必要的修订,给出了分种检索表。模式标本保存于陕西师范大学动物研究所。  相似文献   
9.
Gas exchange analysis was used to characterize photosynthetic and stomatal responses to key environmental stimuli in five commercial lines of Pima cotton ( Gossypium barbadense L.) which represent a gradient of selection for higher yields and heat resistance, and a primitive, uncultivated G. barbadense. At constant light and vapor pressure deficit, stomatal conductance increased linearly with air temperature in the 23 to 36$C range in all five commercial lines, and conductance at each temperature increased as a function of selection. In contrast, photosynthetic rates had a low sensitivity to temperature in the 23 to 36$C range, particularly in the advanced lines. In a segregating F2 population from a cross between the advanced line, Pima S-6, and the primitive cotton, B368, the slope of the stomatal response to temperature in each F2 plant was positively correlated with the stomatal conductance measured at 40$C. An analysis of the frequency distribution of stomatal conductance in F1 and F2 progeny of the cross showed that the differences in stomatal conductance between lines were genetically determined. These data indicate that selection for higher yield and heat resistance in Pima cotton has caused genetically determined changes in stomatal properties. Characterization of the relationship between the altered stomatal properties and the attained increases in heat resistance and yields could make it possible to use these physiological traits as selection criteria in future breeding programs.  相似文献   
10.
金银花作为我国重要的中药材,具有消炎、抗菌、抗病毒、抗氧化、防癌等多种功效。随着金银花市场供需矛盾日益加剧,通过分子标记辅助选择育种方法来培育高产优质品种势在必行。通过NCBI的Blast工具扫描金银花蛋白组数据发掘花形候选基因,并执行候选基因的亲缘关系分析、结构域分析、表达模式分析、理化性质分析、蛋白质结构预测等一系列生物信息学分析。依据拟南芥调控花形的ABE类基因,通过NCBI-Blast工具扫描金银花氨基酸序列,筛选出包含MADS结构域的8个调控花形的金银花候选基因。经LjaFGD表达模式分析发现,金银花的花中GWHGAAZE016592和GWHGAAZE014905表达量显著高于其他部位,可能正向调控金银花花形。GWHGAAZE014905是一个包含MADS结构域的调控花器官发育的B类基因;GWHGAAZE016592是AP3同源基因。生物信息学分析发现,GWHGAAZE016592和GWHGAAZE014905均是稳定的亲水蛋白,属于非分泌蛋白,包括Motif1、Motif3、Motif4、Motif2、Motif6和Motif5,蛋白质三级结构模板为6byy.2.A和4ox0.2.C。GWHGAAZE014905被定位到细胞核上,而GWHGAAZE016592被定位到叶绿体上,且包含1个位于151~173 bp的跨膜螺旋区域,属于膜蛋白。研究结果为分子标记辅助选择方式培育道地高产优质金银花品种提供了基因资源和分子标记。  相似文献   
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