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1.
赵福瑜 《化石》2007,(3):19-21
地球上十二属种动物与人类的关系存在决定意识,人们的社会存在决定人们的社会(思想)意识。人类产生“十二兽”观念并制订,实行十二兽历法,正是人类自身起源于“十二兽”的先祖这一客观事实在人们头脑中的反映。十二兽:我国又称十二禽,十二属,十二物,十二生肖等。所谓十二兽,我国汉族是指鼠,牛,虎,兔,龙,蛇,马,羊,猴,鸡,狗,猪。让我们从十二兽历法的产生和起源来探讨地球上十二属种动物(十二兽)的先祖与人类进化的关系。世界上四大文明古国———中国、印度、埃及和巴比伦各有其“十二兽历法”,内容上大同小异。中国汉族:鼠,牛,虎,兔,龙,蛇,…  相似文献   

2.
<正>当窗外猫头鹰的"咕咕"声和外公的呼噜声配成一首滑稽的奏鸣曲,我知道,夜已经很深了。穿好衣服,提上鞋子,我蹑手蹑脚地溜出家门。今晚,对,趁着夜深人静,我要独自走入森林,找到外公提到过的那棵老橡树。哪怕田鼠啃咬我的脚趾,虫虫钻进我的衣领,我都会在树下屏住呼吸,耐心守候,因为……  相似文献   

3.
烟草趣话     
笔者不会抽烟,不喜欢烟,记得小时候看大人吸烟,那是一小烟袋,铜制的,有个咀子放烟丝,另一头用嘴吸,烟袋里装有水,当用火柴点燃烟丝时,嘴就随时缓缓吸烟,几下子就吞云吐雾了。由于好奇,大人走后,我就仿效试试,由于吸气太大,一下子把烟袋中的水都吸到口里了,满嘴烟味极不好受,以后再不玩这东西了。后来时兴纸烟,当闻到烟气时头就不舒服,从此与烟绝了缘至今。  相似文献   

4.
《生命世界》2012,(10):94-95
野生红豆杉,冰川世纪遗留下来的古老树种,以它顽强的生命力屹立在地球上已几百万年。在人类出现在这个星球以前,它就以红彤彤的红豆果,扮靓了地球的山间和密林。它树姿优美,枝繁叶茂,苍劲挺拔,一派生机盎然,令人敬畏。它果实鲜红,艳丽无比,圆如珍珠,寄托相思之情,令人爱怜。它全身是宝,强身健体,防癌抗癌,历史悠久,令人感动。  相似文献   

5.
本文记了分别采自云南高黎贡山的栅蛛科栅蛛属Hahnia 2新种:垭口栅蛛,新种S.yakouensis sp.nov.和肾形栅蛛,新种S.reniformis sp.nov..垭口栅蛛后眼列前曲,交媾腔大,扁圆形,交媾孔1个,位于交媾腔下缘,交媾管粗,呈"人"字形下行分成2支再向两侧扭曲.纳精囊有一肓管斜向上伸出,鉴于上述特征而与Hahnia mridulae Tikader,1970不同.肾形栅蛛交媾孔2个,位于生殖厣腹面中央,纳精囊1对,大,肾形,插入器始于生殖球左下方,鉴于上述特征而与Hahnia xinjiangensis Wang et Liang,1989不同. Abstract: The present paper deals with two new species of the genus Hahnia collected from the Gaoligong Mountains Region of Yunnan Province, China: Hahnia yakouensis sp. nov., Hahnia reniformis sp. nov..  相似文献   

6.
李秉滔   《广西植物》1983,(3):167-170
<正> 灌木,通常高3米,枝条细,粗3—5毫米,树皮近灰色,具细条纹,小枝具翅,无毛。叶薄纸质,椭圆形至卵状长圆形,无毛;中脉细,两面凸起,侧脉纤细,5—7对,两面稍凸起,未达叶缘而网结,叶柄长不及2毫米,无毛;托叶挟三角形,长3—4毫米,基部扩大,近耳形,顶端急尖。花腋生,单朵或稀2朵簇生,萼片和花盘互生,无花辦。雄花:花梗丝状,长3—3.5厘米,基部被微柔毛;萼片4枚,覆瓦状排列,披针形,长4.5毫米,  相似文献   

7.
青海蚕豆种质资源形态多样性分析   总被引:10,自引:3,他引:10  
对153份青海蚕豆种质资源的形态多样性进行鉴定, 结果表明, 青海蚕豆种质资源具有丰富的形态多样性,平均多样性指数为0.8033,其中青海地方蚕豆品种多样性最丰富,平均多样性指数为0.8288.通过多变量的主成分分析,前6个主成分代表了蚕豆形态多样性的87.89%.基于形态性状,把153份蚕豆种质聚类并划分为3大组群.第Ⅰ组群,初花天数较长,植株中等,子粒中等,单株荚数和粒数多,单株产量较高;第Ⅱ组群,初花天数较短,株高较矮,子粒小,单株荚数和粒数较多,单株产量低;第Ⅲ组群,初花天数较短,株体较高,单株荚数和粒数少,但子粒较大,单株产量较高.  相似文献   

8.
韦裕宗   《广西植物》1984,(3):195-198
<正> 短叶琼楠 新种 图10 Beilschmiedia brevifolia Y. T. Wei, sp. nov. 乔木,高约8米,小枝略粗壮,无毛;树皮平滑或微裂;顶芽卵圆形,无毛,直径约5毫米,先端尖。叶薄革质,对生,常聚生于枝顶,椭圆形至狭椭圆状披针形,2.5—4(6)厘米,宽1.5—2.5(3)厘米,先端钝,基部近圆形,稀近楔形,两面无毛,干时腹面深灰色,背面黑褐色,中脉在叶面微下陷,在下面凸起;侧脉每边约7条,与网脉在两面凸起;叶柄短,长2—5毫米,无毛。花未见。果序顶生或腋生。果近球形,直经约1.5厘米,干后黑色,果  相似文献   

9.
在非洲的坦桑尼亚北部,有一片茂密的森林,名叫丹堵鲁。为了追踪一种名叫岩象鼩的小动物,生物学家格蕾丝已经在这片森林里待了几个星期。此刻的她,双膝跪地、鼻尖儿蹭着泥,正聚精会神地调试着微型摄影机。哈,调试完毕,我简直是天才!格蕾丝咧开嘴巴,得意地咯咯笑着,这下我一定能……哎呦,什么什么东西钻进了我的鼻子,痒、痒,啊——阿嚏!  相似文献   

10.
马志朝  何烈琪  林伟南  刘玮 《蛇志》2008,20(1):17-19
目的 通过对容县2000~2007年84例狂犬病流行病学特点进行分析,探讨流行回升的因素,分析目前防治过程中存在的问题,提出狂犬病的预防对策和措施.方法 收集2000~2007年容县狂犬病疫情报告资料及对狂犬病病例的个案调查资料进行分析.结果 近年来,容县狂犬病疫情明显上升,成为有史以来流行高峰,最高年发病率3.04/10万.发病以农民,学生为主,男性多于女性,全年均有病例发生,无明显季节性,狂犬病暴露动物以犬伤为主,暴露部位以头颈部为最危险,潜伏期最短.结论 为有效预防狂犬病流行,应进一步建立完善犬类的管理的法律、法规,使预防狂犬病进入法制轨道,以有效控制狂犬病流行.伤后未能及时正确处理,暴露后免疫率低,是狂犬病发生的重要原因.加强宣传,提高狂犬病的防控知识,政府部门齐抓共管,采取综合性防控措施,才能有效控制狂犬病的流行.  相似文献   

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It has now been over twenty years since a novel herpesviral genome was identified in Kaposi's sarcoma biopsies. Since then, the cumulative research effort by molecular biologists, virologists, clinicians, and epidemiologists alike has led to the extensive characterization of this tumor virus, Kaposi's sarcoma-associated herpesvirus(KSHV; also known as human herpesvirus 8(HHV-8)), and its associated diseases. Here we review the current knowledge of KSHV biology and pathogenesis, with a particular emphasis on new and exciting advances in the field of epigenetics. We also discuss the development and practicality of various cell culture and animal model systems to study KSHV replication and pathogenesis.  相似文献   

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Comprises species occurring mostly in subtidal habitats in tropical, subtropical and warm-temperate areas of the world. An analysis of the type species, V. spiralis (Sonder) Lamouroux ex J. Agardh, a species from Australia, establishes basic characters for distinguishing species in the genus. These characters are (1) branching patterns of thalli, (2) flat blades that may be spiralled on their axis, (3) width of the blade, (4) primary or secondary derivation of sterile and fertile branchlets and (5) position of sterile and fertile branchlets on the thalli. Application of the latter two characters provides an important basic method for separation of species into three major groups. Osmundaria , a genus known only in southern Australia, was studied in relation to Vidalia , and its separation from the Vidalia assemblage is not accepted. Species of Vidalia therefore are transferred to the older genus name, Osmundaria. Two new species, Osmundaria papenfussii and Osmundaria oliveae are described from Natal. Confusion in the usage of the epithet, Vidalia fimbriala Brown ex Turner has been clarified, and Vidalia gregaria Falkenberg, described as an epiphyte on Osmundaria pro/ifera Lamouroux, is revealed to be young branches of the host, Osmundaria prolifera.  相似文献   

18.
Fifteen chromosome counts of six Artemisia taxa and one species of each of the genera Brachanthemum, Hippolytia, Kaschgaria, Lepidolopsis and Turaniphytum are reported from Kazakhstan. Three of them are new reports, two are not consistent with previous counts and the remainder are confirmations of very scarce (one to four) earlier records. All the populations studied have the same basic chromosome number, x = 9, with ploidy levels ranging from 2x to 6x. Some correlations between ploidy level, morphological characters and distribution are noted.  相似文献   

19.
肝癌中HBV和HCV基因和抗原的分布及意义   总被引:1,自引:0,他引:1  
采用原位分子杂交方法检测HCV RNA及HBV X基因;采用免疫组织化学方法研究HCV核心抗原,非结构区C33c抗原及HBxAg在肝细胞肝癌中的定位及分布.结果表明(1)HCV RNA、HBV X基因在肝细胞肝癌组织检出率分别为40%(55/136)和82%(112/136).HCV RNA定位于癌细胞的胞浆内,阳性细胞呈散在、灶状及弥漫分布三种形式;HBV X基因在肝癌细胞中的分布呈胞浆型、核型及核浆型,阳性细胞也呈上述三种分布形式;(2)HCV C33c抗原、核心抗原在肝细胞肝癌中的阳性率为81%(133/164)及86%(141/164).C33c抗原定位于癌细胞及肝细胞的胞浆内;核心抗原既定位于癌细胞核中,又可定位于胞浆中.C33c抗原阳性细胞以灶状分布为主;而核心抗原阳性细  相似文献   

20.
For a plant selection model with frequency-independent viabilities, fertilities and selfing rates, it is shown that apart from global fixation, for certain parameter combinations a protected polymorphism and facultative fixation (either allele may become fixed according to initial frequencies) may both occur. Facultative fixation requires different selling rates for the dominant and recessive type. Protection of the polymorphism requires resource allocation for male and female function. In this connection the problem of purely genetically caused population extinction is discussed.
For general frequency dependence and regular segregation, the chances for establishment of a completely recessive gene are compared to those of a completely dominant gene. It is proven that the process of establishment of the recessive gene, despite a fitness advantage, may be considerably endangered by drift effects if random mating prevails. The recessive gene may reach the same effectivity in establishment as a dominant gene, only if the recessive homozygote mates exclusively with its own type during the period of establishment.  相似文献   

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