黑龙江省黄鼬冬季毛被分层结构及保温功能

为了解黄鼬毛被的保温机制,选取黑龙江省通河林区黄鼬东北亚种(Mustela sibirica manchurica)冬季皮张,通过观测雄性5个部位和雌性4个部位毛被的分层结构,并结合热物性测试比对,发现了毛被的各层结构具有不同的保温隔热功能且存在部位差异。结果表明:1)毛被由外及里表现出4层结构,各层毛被厚度分别为:(12.7±3.0)mm、(6.0±1.8)mm、(5.5±2.2)mm和(1.4±0.5)mm。2)4层毛被的颜色、结构及保温机制依次为:最外层毛被棕黄色或金黄色,仅由2种类型被毛构成,耐磨损能力较强,保护下层毛被,阻挡冷空气侵入并降低毛被的热量散失;第二层毛被淡黄色,此层开始均由4种类型被毛构成,毛干细度较小,被毛间形成细小空隙,滞留大量静止空气,增强保温功能;第三层毛被灰色或灰白色,4种类型被毛的毛干更细,绒针毛和绒毛弯曲程度更大,使被毛间滞留静止空气的能力更强、更稳定,保温能力更强;最内层毛被为白色,为近毛根处,4种类型被毛均较直,便于热量传递。3)4层毛被的对整体的贡献率分别为:16.11%、27.40%、44.40%和12.09%。4)背面毛被较腹面的颜色深,厚度大,保温能力强;沿吻端至尾基的体轴方向毛被厚度增加,保温性增强。5)雄性毛被较雌性的厚度大,保温能力强。以上,反映了黄鼬冬季多部位毛被由表及里不同的空间布局及各层毛呈现的不同的形态结构,从整体上兼顾保护、保温、散热等多种功能,以适应当地的寒冷环境。     

栎属青冈亚属（壳斗科）的叶表皮研究

利用光镜和扫描电镜观察了栎属青冈亚属Quercus subgen. Cyclobalanopsis 48种植物的叶表皮,尤以对叶下表皮的毛被特征观察较为仔细。共观察到8种不同类型的叶表皮毛：单列毛、单毛、乳突、星状毛、溶和星状毛、具柄束毛、多出毛和水母状毛。其中乳突在青冈亚属中较常见,而在壳斗科其他属中仅在石栎属 Lithocarpus 少数种类中有报道;水母状毛首次在壳斗科中发现。毛被可能遵循以下的演化规律：乳突→单毛→星状毛;星状毛依照从简单→复杂的演化途径,分化出各种形态各异和结构复杂的毛系。初步讨论了毛被以及叶表皮其他特征(如毛基细胞和表皮细胞的形态、气孔的类型和密度等)的分类和系统学意义。     

智囊出招

<正>火狐狸姐姐:同样是毛,有的是皮毛,有的是披毛,有的是被毛;同样是嘴,有的叫吻部,有的叫喙,有的叫口器;同样是鸟,养孩子的才敢叫亲鸟;一年到头不爱旅行就爱宅在家乡的称之为留鸟……厉害了动物们,它们也有专用名词儿!动物身上的毛,应该叫皮毛、披毛还是被毛?皮毛是连皮带毛的意思。动物的皮毛如果被人们用作制衣材料,又被称为皮草(所以为了保护动物,我们必须拒绝皮草)。披毛本意是"披散的毛发",以"披毛"为名的动物,比如披毛犰狳、披毛犀牛(已灭绝),身上都覆有稀疏凌乱的毛。被毛是指哺乳动物(包括人)身上的所有毛发。根据结构特     

广西大瑶山植物区系资料

<正> 蔓生或近直立草本;茎具棱,密生灰白色长硬毛。叶纸质,椭圆形或卵形,长5—9厘米,宽2.5—4厘米,先端钝,基部狭楔形,边缘有疏齿,两面被灰色长硬毛;叶柄长1—1.5厘米,被长硬毛。聚伞花序具4—5朵花,连总梗长约1.5—2.5厘米,总梗及花梗均被长硬毛;花梗长0.8—1.5厘米,花萼钟状,长5—6毫米,脉不明显,萼齿5,近等大,披针形,边缘被长硬毛;花冠白色,长约5厘米,无毛,近二唇形,上唇较短,长约3.5毫米,先端钝,下唇3裂,中裂片长圆形,长约7毫米,宽约4毫长,先端钝圆,雄蕊     

白唇鹿被毛形态学与高寒环境关系的研究

本文对白唇鹿被毛的形态进行了宏观及扫描电镜的观察研究。结果表明,其被毛仅由针毛组成。针毛的毛径特粗;髓质极发达,髓质指数高达96％;髓质形态为蜂窝状网格型;皮质呈退化状态。针毛具有很强的保温性,是适应高寒环境的重要特征之一。     

藏羚冬季绒毛的形态结构

哺乳动物被毛的作用在于发挥其保温、缓冲和隔离的功能,而这些功能会因动物分布地域、不同季节、不同身体部位等的毛形态结构差异,发生适应性变化(Johnson and Homby,1980;Moen and Severing.haus,1984;Chen and Wang,1991;张伟等,1997;汪玺,1998;徐正强等,2006;张伟等,2008).     

哺乳动物毛被传热性能及其影响因素

毛被能够加强或减弱动物向周围环境的热量散失,毛被的形态结构和颜色是传热性能的决定因素,其传热过程往往是传导、对流和辐射3个过程的耦合。以往研究发现环境因子中,风可增加机体向环境中的散热速率,且散失量与风速正相关,且动物通过调节在风场中的姿态来适应不同风向。动物体与环境间的温差是影响散热速率的另一因素,不同环境中的动物通过改变毛被结构来适应温差变化。毛被含水率上升会引起导热和蒸发冷却作用加强,动物通过行为或毛被结构变化来调节毛被含水率。毛色决定毛被吸收和反射热辐射的能力。毛被传热性能直接把动物的生理特点与环境因子关联起来,这对揭示动物的适应、进化都具有重要意义。同时提出,毛被结构和传热性能的研究还有助于仿生学意义的挖掘。因此,今后应重点在毛被结构和物理性能、研究技术与方法以及毛被生物学和仿生学意义等方面开展研究。     

鹿类动物被毛形态学研究进展

鹿类动物是现代占优势的两大陆生反刍食草兽类之一,种类多、分布广,栖息于森林、灌丛、沼泽以及北极冻原等各种生境。在长期适应环境变迁的过程中,鹿类动物特殊的被毛形态结构发挥了重要作用。本文综述了鹿类动物被毛形态学在动物的分类、物种鉴定以及保温保护功能形态学等主要方面的研究现状,并结合北京南海子麋鹿苑的麋鹿Elaphurus davidianus冬季被毛形态特征的显微观察予以分析。最后探讨了今后鹿类动物被毛形态学在系统进化与分类、趋同进化、被毛传热性能以及仿生学等方面的研究趋势。     

漠河地区养殖的北极狐冬季被毛性状与保温性能的关系

被毛是哺乳动物最主要的特征之一,其保温功能对动物适应寒冷环境意义重大。为了探讨北极狐(Alopex lagopus)在被毛性状上如何适应寒冷的气候条件,对大兴安岭漠河地区人工养殖北极狐的背中部直针毛、上层绒毛、下层绒毛的长度、毛根细度、毛干细度以及毛密度、单个毛束内的毛数量、毛束密度、复合毛囊最大横切面积、1mm2内复合毛囊最大横切面总面积等14个性状因子进行测量分析。结果表明,北极狐绒毛分为上下两层,下层绒毛的长度、毛根细度和毛干细度均小于上层绒毛,上层绒毛长度与直针毛接近,直针毛长度与上层绒毛、下层绒毛长度均不存在显著相关性;毛密度与毛束密度极度正相关(P0.01),但与毛根细度、毛干细度、单个毛束内的毛数量和1mm2内复合毛囊最大横切面总面积不存在显著相关性,且与复合毛囊最大横切面积的相关性较小;复合毛囊最大横切面积受毛根细度、单个毛束内的毛数量和毛束密度的影响较小。北极狐不是通过降低毛细度的方式来增加毛密度以加强保温功能,而是通过改变被毛在皮肤内的分布格局来增加毛密度,以及将有髓质的绒毛分为上下两层来改变被毛空间结构这两种策略提高被毛内静止空气的量以加强保温功能,进而适应高纬度地区的寒冷环境。     

湖南杜鹃花属一新种

小灌木,高约1米。幼枝纤细,密被红棕色扁平糙伏毛。叶革质,集生枝端,倒卵形至椭圆状倒卵形或椭圆形,长1—2厘米,宽0.5—1.2厘米,顶端钝尖,有短凸尖头,基部狭楔形,边缘微反卷,被缘毛,上面密被红红棕色糙伏毛,下面疏被红棕色糙伏毛,中脉在上面微隆起,在下面明显隆起,侧脉3—4对,两面微明显,未达叶缘网结,密被糙伏毛;叶柄长2—6毫米,密被红棕色扁平糙伏毛。花芽卵圆形,有较多粘质,鳞片     

Isolation of Toxoplasma gondii from goats from Brazil

Goats are economically important in many countries, and little is known of caprine toxoplasmosis in Brazil. Antibodies to Toxoplasma gondii were assayed in the sera of 143 goats from 3 Brazilian states, using modified agglutination test (MAT titer > or = 1:25); 46 (32.2%) tested positive. Samples of brain, heart, diaphragm, and masseter of seropositive animals were pooled, digested in pepsin, and bioassayed in mice. Viable T. gondii specimens were isolated from tissue homogenates of 12 goats; the isolates were designated TgGtBr1-12. Ten of the 12 isolates killed 100% of infected mice, indicating that goats can harbor mouse-virulent T. gondii and, hence, can serve as a source of infection for humans.     

Isolation of protein from humic acid extracted from soil

Summary Chromatography of humic acid in a phenol containing solvent system reveals, in the case of the three types of soil analyzed, the presence of humoprotein containing 11 per cent of nitrogen. Isolation of a humoprotein complex from humic acid, according to the method used by Kirby, followed by paper chromatography allowed the isolation of a protein fraction containing 14.8 per cent nitrogen. This fraction is not dialysable; it has a maximum absorption in ultraviolet light between 260–280 mµ, a small electronegative charge and gives rise to twenty different amino acids. This is the first time that a protein has been separated from humus. Thereby demonstrating that part of the nitrogen contained in humic acid is in the form of protein protected from decomposition.Research supported by the Institut pour l'Encouragement de la Recherche Scientifique dans l'Industrie et l'Agriculture (I.R.S.I.A.).     

Identification of trypanosomes isolated from reduviidae from north Chile

Examination of 54 Triatoma infestans from a village near the European Southern Observatory La Silla in Chile and of 9 Triatoma spinolai from the territory of the observatory showed that 10 T. infestans were infected with trypanosomatids. Mice were infected with in vitro cultures initiated with five different trypanosomatid isolates and treated with the immunosuppressive drug cyclophosphamide to increase the parasitemia of the flagellates. Evidence of the presence of T. cruzi was provided by a comparative biometrical analysis of blood trypomastigotes and the occurrence of intracellular amastigotes. Three methods for further identification were used: examination of kDNA ultrastructure, disc electrophoresis of soluble proteins and the Aaptos papillata II lectin induced agglutination. We obtained the following results for all isolates: (1) presence of a central band of the kDNA; (2) T. cruzi specific double bands of the protein patterns; (3) positive reaction with Aaptos papillata II. No differences between the five isolates from Chile and T. cruzi or T. cruzi-like strains from other countries could be observed. Based on these results an infection of the bugs with T. rangeli and T. conorhini could be excluded.     

Guaianolides from two subspecies of Amphoricarpos neumayeri from Montenegro

Quantitative (1)H NMR measurements revealed delta(11(13)) sesquiterpene gamma-lactones as the main constituents ( >or= 1% per weight of dried plant material) in the crude extracts of the aerial parts of Amphoricarpos neumayeri ssp. neumayeri and ssp. murbeckii from mountains Orjen and Visitor (Montenegro), respectively. Preparative silica gel chromatography afforded thirteen guai-11(13)-en-12,6alpha-olides, named amphoricarpolides (1-13), with the same relative (1alphaH,4betaH,5alphaH,7betaH) configuration of the basic skeleton. The common structural feature of lactones 2-13 was 3beta,15-dioxygenation pattern. The only exception was 1 (3-deoxyamphoricarpolide), containing a single oxygen substituent (15-OH). Eight of them exhibited an additional oxygen substituent, 9beta-OH (5 and 6), 2alpha-OH (8-12), or 2alpha-OAc (13). Compound 7 was epoxydated at 10alpha(14)-position, whereas the remaining lactones contained a 10(14) double bond.     

Isolation of intact plastids from protoplasts from castor bean endosperm

Protoplasts were prepared from castor bean (Ricinus communis) endosperm by treatment with a mixture of the commercial enzymes Macerozyme R-10 and Cellulose “Onozuka” R-10. The protoplasts were gently ruptured by forcing the suspension through a hypodermic needle and the homogenate centrifuged on a linear sucrose gradient. From such a homogenate the mitochondria are recovered at their typical isopycnic density of 1.18 g/ml, but the glyoxysomes are retained, with other membranes, at a density of 1.13. The plastids reach their typical density of 1.22 on the gradient and are thus clearly separated from other organelles. Moreover, since essentially all of the ribulose bisphosphate carboxylase activity on the gradient is present in this fraction it can be concluded that the plastids are intact and have been recovered in high yield.