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小地老虎[Agrotis ypsilop (Rottemberg)]、粘虫[Mythimna separata(Walker)]及黄粉(虫甲)(Tembrio molitor L.)的幼虫经灭幼脲处理后,含几丁质组分的体壁表皮层、气管壁内膜和中肠围食膜等组织,分泌激素的咽侧体、前胸腺等内分泌腺体,以及代谢器科管脂肪体,都分别出现明显可辨的组织学改变和病理症状,同是地表现一些差异程度并不显著的现象.根据中毒症状和组织学的改变,本文详细分析和讨论了死幼脲处理后对上述两种夜蛾幼虫和一种拟步(虫甲)幼虫的毒理学基础.  相似文献   

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The external features of the subterranean organs of coastal Californian Pholisma depressum Greene are described. A dimorphic root system exists. Long, stout roots (pilot roots) serve for vegetative propagation in reaching other host roots. Short, unbranching, more slender roots originating from the pilot roots are haustorial in function. Shoots seem to arise only on pilot roots. Host attachment is achieved through the direct transformation of the apical meristem of haustorial roots into the haustorial organ. The basal part of the shoot is also able to produce roots when near host roots, and may form lateral branch shoots either directly or after new haustorial connections are formed. Both types of roots arise endogenously. The invaded host root undergoes considerable hypertrophy. The intrusive organ itself forms a massive but irregular body. More than one haustorial root may enter even a small host root. Self parasitism may occur but is not common.  相似文献   

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本文采用Ag-Hb(血红蛋白)饱和法,Cd-Hb饱和法、Cu-Hb饱和法及酶联吸附免疫法定量分析刺猬各组织器官中金属硫蛋白含量。结果表明,肌肉注射三种金属盐均有明显的诱导金属硫蛋白合成的作用,诱导强度为Cd^2+>Zn^2+>Cu^2+,诱导后金属硫蛋白含量分布规律一致,即肝>肾>睾丸>脾>心、肺、胃、膀胱、胆汁、大肠、小肠、肌肉、血液,其中镉诱导肝的金属硫蛋白含量每克湿组织约1.84mg,为肾的  相似文献   

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DISTRIBUTION AND TURNOVER OF OCTOPAMINE IN TISSUES   总被引:9,自引:4,他引:5  
Abstract— Octopamine is a normally occurring amine in several species of animals. Particularly high concentrations are found in the crustacean central nerve cord. In the rat it is specifically localized to sympathetic nerve endings, has a subcellular distribution similar to that of norepinephrine, and is asymmetrically distributed in the CNS. It has a turnover rate in heart about six times that of norepinephrine. The physiological role of octopamine has not been established but it appears likely that it is a cotransmitter together with norepinephrine in the peripheral sympathetic nervous system.  相似文献   

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Pontederia cordata is a tristylous, self-incompatible emergent aquatic. Measurements of reproductive organs in mature flowers and developing buds and analysis of relative growth rates of the styles, filaments, and floral tube were used to analyze the developmental processes that result in reciprocal positioning of reproductive parts among the style morphs. Flowers are trimerous with two series of three tepals, two series of three stamens, and a tricarpellate ovary with a single ovule. Each flower has stamens of two lengths, but the two lengths correspond to upper vs. lower position in the zygomorphic flowers, not to the two series initiated in the primordium. Morph-dependent variation in stigma height depends on differences in style length, not ovary length. Differences among morphs in anther height result from differences in the position of filament insertion on the floral tube and differences in filament length. Styles of the three morphs develop to different lengths as a result of two distinct processes. Styles of L and M morphs develop at different rates with the L style growing more rapidly than the M style, whereas styles of the S morph have a brief period of rapid growth followed by early inhibition. Stamen growth in the S morph also differs qualitatively from that in the L and M morphs, which are distinguished from each other by quantitative differences in growth rates. Results indicate that the developmental processes that result in the complementary arrangements of organs in different morphs are morph-specific. An attempt is made to integrate the findings of this study with the model for genetic control of tristyly.  相似文献   

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采用垂直板聚丙烯酰胺凝胶电泳和紫外分光光度法分析大鲵15种组织的乳酸脱氢酶(LDH)同工酶后发现:在正常生理条件下,大鲵体内只有H4和M4两种同工酶,红细胞只有M4一种同工酶;大鲵体内LDH同工酶中,以M4占绝对优势;除生殖腺及脑外,在幼体至成体的发育过程中,LDH同工酶未见变化;大鲵体内各组织LDH含量及前述两种同工酶相对含量不同。  相似文献   

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The involvement of the stamens as transporters of plant growth regulators in flowers was examined by measuring the movement of 14C-indole-3-acetic acid (IAA) and l4C-l-aminocyclopropane-1-carboxylic acid (ACC) through floral organs of Ipomoea nil. During the transport of 14C-IAA through isolated filament segments, the polar accumulation of 14C-IAA in receiver blocks increased with time during filament development, which correlated with polar efflux rates at older stages of filament development. An inhibitor of polar IAA transport, 2,3,5-triiodobenzoic acid, disrupted the polarity of auxin transport by reducing the movement of 14C- IAA from filaments into receiver blocks. Transport of both 14C-IAA and l4C-ACC through filaments into other floral organs also was monitored in isolated flower buds in the laboratory and intact buds in the greenhouse. In isolated and intact buds 21 hr before anthesis, substantially higher levels of isotope were recovered in corolla tissue when 14C-ACC was transported through the filaments than when 14C-IAA was transported from the filaments. In isolated buds, substantial levels of both isotopes accumulated in the pistil (69 hr and 45 hr before anthesis), but minimal amounts were observed in receptacle and calyx tissues (69 hr to 21 hr before anthesis). In intact buds, high levels of both isotopes were recovered in receptacle, calyx, and pistil tissues (69 hr to 21 hr before anthesis). The results from this study support the hypothesis that Ipomoea stamens are transporters for ACC and IAA to regulate ethylene production in the corolla and other floral tissues.  相似文献   

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Disorders of the scrotal contents in infancy and childhood parallel fairly closely those found in adults and deserve equal consideration. Hydroceles, epididymitis, hernia and cryptorchism are the more common conditions, but injuries, torsion of the spermatic cord and malignant tumors also occur in this age group.Early, accurate diagnosis and definitive treatment increase the prospect for children with testicular disease to develop into healthy, fertile adults.  相似文献   

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鸡中枢淋巴器官肥大细胞的组织化学与形态学   总被引:7,自引:0,他引:7  
对哺乳动物的,特别是啮齿动物和人类肥大细胞已有了比较深入的研究, 但关于家禽肥大细胞的研究很少.本研究旨在阐明鸡中枢淋巴器官中肥大细胞的组织化学与形态学特征.本研究证实Carnoy 氏液是鸡肥大细胞的优良的固定液,而中性缓冲福尔马林(NBF) 却阻断了大多数肥大细胞的着染力.甲苯胺蓝和阿尔新蓝是鸡肥大细胞的良好的染料,但阿尔新蓝能使更多的肥大细胞着染,虽然其也可使杯状细胞着染.作者的一种新的染色法, 长时间阿尔新蓝染色(LAB-S)可用于NBF固定的组织中肥大细胞的染色,因为其着染的细胞数与Carnoy 氏液固定甲苯胺蓝染色的细胞数无显著差异(P<0.001).在胸腺髓质中见有大量的肥大细胞,而胸腺皮质仅可见个别肥大细胞位于血管周围及小叶间结缔组织中.腔上囊的皮质与髓质中很少见有肥大细胞.肥大细胞有血管周围分布的倾向,但一个有趣的发现是血管内偶尔也有个别肥大细胞.电镜下可见肥大细胞的胞浆颗粒内充满无定形的颗粒状基质,但其电子密度有的较高,有的较低.少数胞浆颗粒内有旋涡状及网状亚微结构.但未见有人类肥大细胞胞浆颗粒内特征性的晶格状和卷轴状的亚微结构,也未见到在绵羊肥大细胞中描述过的特殊亚微结构.  相似文献   

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A stereological, morphometric study of the ultrastructure of subapical cells, xylem parenchyma, and cortical chlorenchyma of Echinocereus engelmannii shows that each of these cell types has a unique organellar composition. The cells of any of these tissues are unique not only in vacuolation (which is visible at the light microscope level), but also in the nucleus/cytoplasm ratio and the concentrations of mitochondria, chloroplasts, and dictyosomes. Furthermore, the differences between each of these cell types were large and statistically significant. It had previously been found that the cells of each zone of the shoot apical meristems of E. engelmannii are different from those of the other zones, but the present study suggests that, considering the large ranges of structure possible in the nonapical cells of this species, the apical meristem variation should be considered as only a minor difference and that the meristem zones are really quite similar to each other.  相似文献   

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咽部活组织中细菌L型的检出及意义   总被引:2,自引:0,他引:2  
应用病原微生物培养、电镜、组织切片细菌学检查及L型抗体免疫组化染色等方法,检测64例慢性咽炎组织的细菌L型。结果有42例培养出细菌L型,其阳性率为65.6%;它与切片革兰氏染色L型检出阳性率(67.2%)无显著性差异,P>0.05。透射电镜在慢性咽炎组织的间质及上皮细胞、巨噬细胞等细胞内见皮细菌L型;且L型抗体免疫组化染色亦证实组织中有细菌L型抗原。提示,细菌L型感染与慢性咽炎关系密切,L型侵入组织并在宿主细胞内生长的特征,可能是慢性咽炎反复发作,迁延不愈的重要原因。  相似文献   

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