蝴蝶兰原球茎状体的诱导及增殖

利用蝴蝶兰的植株的不同部位,采用不同培养基对其进行诱导和增殖效果比较。结果表明,香蕉泥和椰胚乳(CM)对于蝴蝶兰外植体原球茎状体的形成具有明显的促进作用。在MS 6 BA5.0mg L NAA2.0mg L 香蕉泥10.0% AC0.3%的培养基中,叶片原球茎状体的诱导率可达48.6%;花梗腋芽和茎尖适宜的诱导培养基配方均为MS 6 BA5.0mg L NAA2.0mg L CM15.0% AC0.3%,其原球茎状体的诱导率分别达72.2%和64.3%。     

葡萄离体培养中胚状体发生的研究Ⅰ.胚状体发生的组织细胞学观察

以葡萄（ＶｉｔｉｓｖｉｎｉｆｅｒａＬ．）的花药和花丝为实验材料，观察了葡萄离体培养中胚状体的发生发育过程．结果表明：（１）葡萄的花药和花丝经诱导都可形成胚性和非胚性两类不同的愈伤组织，与外植体来源无关，胚状体经胚性愈伤组织产生．（２）胚状体多起源于胚性愈伤组织表层或表层以下的单个细胞，这些细胞核大，细胞质浓，染色深，在表层者易于脱落而处于单个离散状态，它们的第一次分裂有均等分裂，也有不等分裂，经２细胞、３细胞、多细胞原胚等阶段发育为成熟的胚状体．（３）葡萄胚状体具有与双子叶植物合子胚相似的发育过程     

低剂量辐射后小鼠骨髓造血干、祖细胞的蛋白质组学研究

本文利用双向凝胶电泳方法建立低剂量辐射后不同时间点小鼠骨髓造血干、祖细胞与相应假照组细胞蛋白质组二维凝胶电泳图谱,用图像分析软件分析照射组与假照组差异表达蛋白,并利用MALDI-TOF-MS生物质谱对差异蛋白质进行鉴定分析.结果表明低剂量辐射后骨髓造血干、祖细胞中表达上调的蛋白26个,表达下调的蛋白4个,消失的蛋白4个.其中碳酸酐酶II、蛋白二硫键异构酶、层粘连蛋白受体、嘌呤核苷磷酸化酶、谷胱甘肽过氧化物酶、氯化琥珀胆碱细胞内信号通道蛋白、中心体肌动蛋白-α、磷酸葡萄糖脱氢酶、原纤维蛋白、丝氨酸蛋白酶抑制剂等22种蛋白被鉴定出来.研究表明低剂量辐射使骨髓造血干、祖细胞某些蛋白表达上调或下调,并鉴定出与低剂量辐射作用机制相关的蛋白质.从新的视角探讨了低剂量辐射对造血系统的作用机制,同时也为低剂量辐射作用机制的研究提供了一种新的有效的研究手段.     

内外因素对植物胚状体发生的影响

就内外因素对植物胚状体发生和发育的影响,尤其生长调节剂、含氮化合物和金属离子的应用效果作了概括性的介绍。     

黄花菜的离体培养中胚状体的发生和再生植株形成的研究

将黄花菜的幼嫩花梗及花托培养在Ｎ６＋２．４－Ｄ２＋６－ＢＡ１培养基上，已经诱导出大量胚状体，在相同培养基上继代培养，建立了黄花菜胚状体元性系．成熟的胚状体，转到１／２ＭＳ＋ＮＡＡ０．２培养基上，长成了带有根系的完整植株．再生植株成功地移栽到土壤基质中，成活率达９０％以上．     

实验小鼠念珠状链球杆菌和鼠痘病毒混合感染的诊断

经细菌分离,生化鉴定,血清学,动物组织,病理学检查,发现一起由念珠状链球杆菌和鼠痘病毒混合感染而导致的实验小鼠发病死亡     

黒腹果蝇黑条体突变型蛋白质组分析中二维凝胶电泳技术的改进

用黒腹果蝇黑条体突变型为材料,介绍一种改进的蛋白质组分析中的二维凝胶电泳技术。该方法在电解质的配比以及银染过程等方面对传统的二维凝胶电泳技术加以了改进,不仅缩短了实验时间,减轻了实验工作量,而且得到了更好的实验效果;并且该方法对实验条件要求不高,在普通的实验室条件下即可被运用。     

大花君子兰的胚培养及其胚状体的诱导

大花君子兰幼胚培养,其胚状体采用MS培养基(其中大量元素减半),附加ZT1毫克/升,NAA0.2毫克/升,IAA0.2毫克/升,蔗糖1.5％、琼脂0.65％、pH5.8％,在温度25±1℃、光照1200 Lx(10小时/天)下培养20天后即诱导出芽,然后转入壮苗发根培养基:MS培养基(其中大量元素减半)、附加BA0.05毫克/升、IBA0.2毫克/升、IAA0.6毫克/升,蔗糖、琼脂、pH及培养条件同上。培养三个星期后即长出叶片并发根2—3条。将试管苗鳞茎状部分切成0.5—1 cm见方的小块,接入壮苗发根培养基中,经2—3次(每次20天)继代培养形成8—9个胚状体,然后移至无激素的MS培养基中培养(培养条件同上),19天后转入壮苗发根培养基中,16天后相继长出根和叶,成为壮苗。最后经炼苗移栽至花盆,成活率可达100％。     

自主攀爬运动对小鼠体成分的影响

目的:通过饮食诱导小鼠以攀爬运动形式进行抗阻训练,观察自主攀爬运动对小鼠体成分的影响.方法:小鼠分为攀爬组(E)和对照组(C),攀爬组逐渐递增攀爬高度.分别在7、12周后用双能X射线吸收法(DEXA)测试小鼠体成分,肌肉采样称量湿重并计算肌肉肥大比率.结果:7周自主攀爬训练后,DEXA测试数据显示小鼠脂肪质量、脂肪百分比低于对照组(分别P ＜0.01,P＜0.05),且小鼠胫骨前肌湿重及肥大比率均高于对照组(分别P ＜0.05,P＜0.01);12周自主攀爬训练后,攀爬组小鼠瘦体重高于对照组(P＜0.05),脂肪质量、脂肪百分比低于对照组(均P＜0.01).攀爬组小鼠腓肠肌、比目鱼肌、胫骨前肌、趾长伸肌、肱三头肌肥大比率高于对照组(P＜0.01),肱二头肌肥大比率高于对照组(P＜0.05).结论通过饮食诱导的小鼠自主攀爬运动引起肌肉肥大,增加瘦体重和肌肉质量,减少脂肪质量及脂肪百分比.因此可认为小鼠这种对抗自身体重的自主攀爬是一种应激小、对体成分有良好影响的递增负荷运动训练模型.     

中国北方气候楔状体的发育特征及气候意义(英文)

气候楔状体是由于气候原因造成的在地层中保存的楔状沉积物。其形态、规模、沉积物质特征各异。在中国北方、气候楔状体分布的南界大致在37°30′N,西界为107°20′E左右,在此以北、以东广泛发育着不同类型的气候楔状体。换言之,在这个区域内气候楔状体存在形态上和沉积特征上的差异。根据楔状体的充填物质特征可将中国东北、华北气候楔分为三类:1、冰楔;2、冰楔假形;3、砂(土)楔。三者都是不同气候作用的产物,同时存在着时间上的继承性。一般认为,气候楔状体的形成在年平均气温低于-5℃的地区.在相对湿冷的环境下利于冰楔和冰楔假形的形成;相反在相对干冷的环境下利于形成砂(土)楔。在中国东北、华北以上三种类型的楔状体在空间上存在着东西差异。大兴安岭以东冰楔、土楔分布较多,以西砂楔为主。楔状体类型的空间差异反映出中国北方在晚更新世晚期东部湿冷而西部干寒的气候特征。     

Acetylcholine inhibits identified interneurons in the cat lateral geniculate nucleus

The transmission of visual information from retina to cortex through the dorsal lateral geniculate nucleus (LGNd) is controlled by non-retinal inputs. Enhanced visually evoked responses in cat LGNd relay cells during periods of increased alertness have been attributed in large part to increased rate of acetylcholine (ACh) release by fibres ascending from the brainstem reticular formation. ACh can modulate geniculate visual responses in vivo, but comparatively little is known about the underlying ionic mechanisms of these cholinergic actions. Although direct excitation of LGNd relay neurons has been shown in vitro, the situation is complicated because cholinergic axons form numerous and complex synapses not only with relay cells, but also with inhibitory interneurons, and electrical activation of the brainstem cholinergic neurons reduces inhibitory postsynaptic potentials in the LGNd. We report here that morphologically characterized interneurons in the cat LGNd possess distinctive electrophysiological properties in comparison with those of relay cells and are inhibited by ACh through a muscarinic receptor-mediated increase in potassium conductance. Together the direct excitation of relay cells and inhibition of intrageniculate interneurons allow the ascending cholinergic system to exert a powerful facilitatory influence over the transfer of visual information to the cerebral cortex.     

Eye-specific effects of binocular rivalry in the human lateral geniculate nucleus

When dissimilar images are presented to the two eyes, they compete for perceptual dominance so that each image is visible in turn for a few seconds while the other is suppressed. Such binocular rivalry is associated with relative suppression of local, eye-based representations that can also be modulated by high-level influences such as perceptual grouping. However, it is currently unclear how early in visual processing the suppression of eye-based signals can occur. Here we use high-resolution functional magnetic resonance imaging (fMRI) in conjunction with a new binocular rivalry stimulus to show that signals recorded from the human lateral geniculate nucleus (LGN) exhibit eye-specific suppression during rivalry. Regions of the LGN that show strong eye-preference independently show strongly reduced activity during binocular rivalry when the stimulus presented in their preferred eye is perceptually suppressed. The human LGN is thus the earliest stage of visual processing that reflects eye-specific dominance and suppression.     

主成分分析法在成年男性体型聚类中的应用

针对GB/T1335.1-1997男装号型标准中,体型分类指标单一,体型分类不够细致的现状,利用三维人体扫描技术采集了成年男性长度、围度、宽度、厚度等方面的人体数据,采用主成分分析从中提取了不同体型聚类指标,进行了相应的体型聚类分析.所得结果表明,应用主成分分析法进行成年男性体型聚类可改进当前国标体型分类指标单一的不足,达到细化体型分类的目的,完全符合大规模量身定制时代对体型分类的要求.     

Synaptic connectivity of a local circuit neurone in lateral geniculate nucleus of the cat

Although receptive fields of relay cells in the lateral geniculate nucleus of the cat nearly match those of their retinal afferents, only 10-20% of the synapses on these cells derive from the retina and are excitatory. Many more (30-40%) are inhibitory and largely control the gating of retinogeniculate transmission. These inhibitory synapses derive chiefly from two cell types: intrinsic local circuit neurones and cells in the adjacent perigeniculate nucleus. It has been difficult to study the functional organization of these inhibitory pathways; most efforts have relied on indirect approaches. Here we describe the use of direct techniques to study a local circuit neurone by iontophoresing horseradish peroxidase (HRP) into it, which completely labels the soma and processes of cells for subsequent light- and electron microscopic analysis. Although the response properties of the labelled cell are virtually indistinguishable from those of many relay cells, its morphology is typical of 'class 3' neurones (see Fig. 1 legend), which are widely believed to be interneurones (but see ref. 12). Here, we refer to the cell as a 'local circuit neurone', which allows for the possibility of a projection axon, rather than as an 'interneurone', a term that commonly excludes a projection axon. We find that the labelled cell has a myelinated axon, but that the axon loses its myelin within 50 microns of the soma and has not yet been traced further. The dendrites of the labelled cell possess presynaptic terminals that act as intrinsic sources of inhibition on geniculate relay cells. We also characterize other morphological aspects of this inhibitory circuitry.     

Temporal properties of pattern adaptation of relay cells in the lateral geniculate nucleus of cats

The temporal properties of pattern adaptation of relay cells induced by repeated sinusoidal drifting grating were investigated in the dorsal lateral geniculate nucleus (dLGN) of cats. The results showed that the response amplitude declined and the response latency prolonged when relay cells were pattern-adapted in dLGN, like the similar findings in visual cortex. However, in contrast to the result in cortex, the response phase of relay cells advanced. This implies that an inhibition with relatively long latency may participate in the pattern adaptation of dLGN cells and the adaptation in dLGN may be via a mechanism different from that of visual cortex.