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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   

11.
以几丁质为底物,加入基本盐培养基中,诱导球孢白僵菌(Beauveriabassiana)产生分解昆虫表皮的蛋白酶。诱导物中,蝉蜕诱导的蛋白酶总活性、比活较高,经超滤、离子交换层析、亲和层析、制备性IEF电洗脱纯化了一种有凝乳弹性蛋白酶(Pr1)活性的蛋白酶BbPr1。经SDS-PAGE电泳银染后是单带,HPLC凝胶过滤显示单峰。BbPr1为单体酶,分子量为33.6kD左右,pI为7.4。底物专一性测定显示,BbPr1能水解Phe或Leu形成的酸胺键和肽键。BbPrl可被PMSF抑制,表明其活性中心有Ser残基;BbPr1还可被胰凝乳蛋白酶抑制剂TPCK和凝乳弹性蛋白酶抑制剂TEI等所抑制;胰蛋白酶抑制剂beupeptin和Epianstatin,及胃蛋白酶抑制剂Pepstain对BbPr1活性无影响。还研究了BbPr1的最适作用pH和pH稳定性。  相似文献   

12.
绿僵菌分解昆虫外壳蛋白酶MAP-21的纯化与特性   总被引:5,自引:0,他引:5  
以蝉蜕为底物诱导绿僵菌产生分解昆虫外壳蛋白酶 。发酵液经超滤、Ultrogel AcA 54凝胶层析、制备IEF电泳,纯化了一种蛋白酶MAP-21,SDS-PAGE电泳后经银染色呈单带。该酶的Mr为27kD左右,pI为76。它的特异识别氨基酸为Arg,其活性可被PMSF和TLCK抑制,表明其活性中心有Ser和His残基。它还可被胰蛋白酶的典型抑制剂Leupeptin、Antipain及STI等所抑制,而胰凝乳蛋白酶抑制剂TPCK和胰凝乳弹性蛋白酶抑制剂TEI对其活性无影响。专一底物和抑制剂特性试验结果表明MAP-21是类胰蛋白酶。此外,该酶还可被EDTA所抑制,表明金属离子为其活性所必需。另外还研究了MAP-21的最适作用温度和pH,以及温度耐受性等特性。  相似文献   

13.
14.
A phenoloxidase has been extracted, purified, and characterized from cuticle of last-instar larvae of the red-humped oakworm, Symmerista cannicosta. It is a typical tyrosinase (EC 1.10.3.1., o-diphenol:O2 oxidoreductase), active toward o-diphenols but not p-diphenols, inhibited by thiourea and phenylthiourea, with a pH optimum between 6.0 and 7.2. In these respects it resembles enzyme A of C. vicina, one of the few species from which this presumed wound healing enzyme has been purified and characterized. Hydrolysis of either exuviae or intact cuticle from last instar larvae yielded a number of ketocatechols of which the most abundant, 2-hydroxy, 3′,4′-dihydroxyacetophenone, represented 2.9% of the dry weight of head capsule exuviae, 0.3% of exuviae from the remainder of the body, and 4.6% of the dry weight of head capsule cuticle from previously frozen intact larvae. Differences in the type and amount of ketocatechol recovered from these cuticles are described.  相似文献   

15.
In recent years, animal ethics issues have led researchers to explore nondestructive methods to access materials for genetic studies. Cicada exuviae are among those materials because they are cast skins that individuals left after molt and are easily collected. In this study, we aim to identify the most efficient extraction method to obtain high quantity and quality of DNA from cicada exuviae. We compared relative DNA yield and purity of six extraction protocols, including both manual protocols and available commercial kits, extracting from four different exoskeleton parts. Furthermore, amplification and sequencing of genomic DNA were evaluated in terms of availability of sequencing sequence at the expected genomic size. Both the choice of protocol and exuvia part significantly affected DNA yield and purity. Only samples that were extracted using the PowerSoil DNA Isolation kit generated gel bands of expected size as well as successful sequencing results. The failed attempts to extract DNA using other protocols could be partially explained by a low DNA yield from cicada exuviae and partly by contamination with humic acids that exist in the soil where cicada nymphs reside before emergence, as shown by spectroscopic measurements. Genomic DNA extracted from cicada exuviae could provide valuable information for species identification, allowing the investigation of genetic diversity across consecutive broods, or spatiotemporal variation among various populations. Consequently, we hope to provide a simple method to acquire pure genomic DNA applicable for multiple research purposes.  相似文献   

16.
Many insects eat their cast cuticle (exuviae) after moulting. The functional significance of this behaviour has not been addressed experimentally. I tested the hypothesis that exuviae eating constitutes a meal, so the animal recycles its nitrogen content. Nitrogenous compounds (protein and chitin) are major components of the cuticle in Periplaneta americana, accounting for as much as 87% of the total weight. It was found that insects almost invariably ate their exuviae during their larval life. The frequency of the behaviour decreased in newly emerged adults and varied between the sexes, males eating their exuviae less frequently than females. This may be due to the extra nitrogen endowment which females need for reproduction. Aposymbiotic animals, which lack the supply of essential amino acids from endosymbiotic bacteria, always ate their exuviae regardless of sex. When animals were reared on different diets throughout their larval life protein level in the diet correlated with exuviae eating. Animals reared on a low protein diet showed the highest levels of exuviae eating; animals reared on a high protein diet showed the highest levels of exuviae rejection. Analysis of the frass produced after exuviae meals showed that over 58% of the nitrogen present in the exuviae was recycled. This demonstrated that cockroaches digested nitrogenous compounds contained in the cuticle. The possibility that the exuviae meal has other functions is discussed, although the evidence supports a nutritional role.  相似文献   

17.
18.
Terrestrial isopods moult first the posterior and then the anterior half of the body. During the moulting cycle they retain a significant fraction of cuticular calcium partly by storing it in sternal CaCO3 deposits. We analysed the calcium content in whole Ligia hawaiiensis and the calcium distribution between the posterior, the anterior ventral, and the anterior dorsal cuticle during four stages of the moulting cycle. The results indicate that: (1) overall, about 80% of the calcium is retained and 20% is lost with the exuviae, (2) in premoult 68% of the calcium in the posterior cuticle is resorbed (23% moved to the anterior ventral cuticle, 17% to the anterior dorsal cuticle, and the remaining 28% to internal tissues), (3) after the posterior moult 83% of the calcium in the anterior cuticle is shifted to the posterior cuticle and possibly to internal storage sites, (4) following the anterior moult up to 54% of the calcium in the posterior cuticle is resorbed and used to mineralise the new anterior cuticle. 45Ca-uptake experiments suggest that up to 80% of calcium lost with the anterior exuviae may be regained after its ingestion. Whole body calcium of Ligia hawaiiensis is only 0.7 times that of the fully terrestrial isopods. These terrestrial species can retain only 48% of whole body calcium, suggesting that the amount of calcium that can be retained by shifting it between the anterior and posterior integument is limited. We propose that fully terrestrial Oniscidea rely to a larger degree on other calcium sources like internal stores and uptake from the ingested exuviae.  相似文献   

19.
Nine isolates of the entomopathogenic deuteromycetes Metarhizium anisopliae, Beauveria bassiana, Verticillium lecanii, Nomuraea rileyi, and Aschersonia aleyrodis produced basic (pI greater than 7.0) chymoelastases that possessed extended binding sites, comprising at least four or five subsites, with preference for hydrophobic residues at the primary binding site. Most isolates also produced additional acidic enzymes with similar specificities against ester and amide substrates but which lacked activity against elastin. Both acidic and basic enzymes degraded high protein azure or locust cuticle and, as shown by inhibition studies, possessed essential serine and histidine residues in the active site. In spite of similarities in catalytic properties antibodies generated against a Metarhizium chymoelastase cross-reacted only with enzymes from two (out of four) Metarhizium isolates; enzymes from all other isolates did not cross-react. Two isolates of Metarhizium produced a third class of protease which degraded Bz-AA-AA-Arg-NA substrates (AA, various amino acids) and hide protein azure. Analogous peptidases were produced by other isolates but they were specific for Bz-Phe-Val-Arg-NA and showed less sensitivity to trypsin inhibitors. The possible significance to pathology of the presence of diverse yet similar protease forms in five genera of entomopathogens is discussed.  相似文献   

20.
侯春晓  殷颖  齐秋月  宋红生  王成树 《菌物学报》2018,37(12):1688-1694
蝉虫草(蝉花)是我国重要的传统中药材之一,用于治疗慢性肾炎等,但对其活性成分的研究仍不充分。本文采用硅胶柱、凝胶柱、ODS柱分离,以及HPLC等色谱技术,对蝉虫草子实体样品的乙酸乙酯提取物进行分离纯化,得到3个化合物。根据波谱学数据,化合物1-3分别鉴定为(E,E)-9-酮-10,12-十八碳二烯酸(E,E)-9-oxooctadeca-10,12-dienoic acid(1)、麦角甾醇ergosterol(2)和白僵菌酮bassiatin(3),其中化合物1为首次从蝉虫草中分离获得。抑菌实验表明,3个化合物均对革兰氏阴性大肠杆菌Escherichia coli和革兰氏阳性枯草芽孢杆菌Bacillus subtilis有显著的抑菌活性,化合物1和3还对条件致病真菌白色念珠菌Candida albicans有明显的抑菌活性。本文的研究结果丰富了蝉虫草的活性化合物组成。  相似文献   

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