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1.
2.
Thomas Eisner Daniel J. Aneshansley Jayne Yack Athula B. Attygalle Maria Eisner 《Chemoecology》2001,11(4):209-219
Summary. The defensive glandular apparatus of primitive bombardier beetles of the tribe Crepidogastrini (Carabidae) is described for
the first time. As exemplified by two African species (Crepidogaster ambreana and C. atrata), the apparatus conforms to the basic bombardier plan, in that the glands are bicompartmented and the secretion is quinonoid
(it contains 1,4-benzoquinones and hydrocarbons), hot, and discharged audibly. In a number of morphological respects the crepidogastrine
apparatus resembles that of the classical bombardiers of the tribe Brachinini (rather than that of bombardiers of the paussoid
lineage), reinforcing the view, already held on taxonomic grounds, that the Crepidogastrini and Brachinini are closely related.
That the Crepidogastrini may be primitive relative to Brachinini is underscored by the finding that, unlike brachinines, crepidogastrines
do not pulse their secretory emissions. Moreover, they discharge their secretion as a mist, rather than forcibly in the form
of jets.
Received 22 May 2001; accepted 29 May 2001. 相似文献
3.
2,2′-Dichlorodivinylarsine chloride (Lewisite II) react by room temperature quickly with alcohols in an equilibrium reaction to yield 2,2′-Dichlorodivinylarsine ether. The reactions are not quantitative. The methyl-, ethyl-and propylether are not stable. 相似文献
4.
Arsenic geochemistry and health 总被引:19,自引:0,他引:19
Arsenic occurs naturally in the earth's crust and is widely distributed in the environment. Natural mineralization and activities of microorganisms enhance arsenic mobilization in the environment but human intervention has exacerbated arsenic contamination. Although arsenic is useful for industrial, agricultural, medicinal and other purposes, it exerts a toxic effect in a variety of organisms, including humans. Arsenic exposure may not only affect and disable organs of the body, especially the skin, but may also interfere with the proper functioning of the immune system. This paper, therefore, generally highlights the toxic effects of arsenic as well as its mobilization in the natural environment and possible controls. It also briefly attempts to outline the impact of arsenic on the immune system, whose alteration could lead to viral/bacterial infections. 相似文献
5.
Defense Mechanisms of Arthropods, no. 96; no. 95: Eisner et al.: Chemoecology (in press) 相似文献
6.
Rainer Haas Alfred Krippendorf Torsten C. Schmidt Klaus Steinbach Eberhard v. Löw 《Environmental Sciences Europe》1998,10(5):289-293
Arsenic containing chemical warfare agents (cwa) are persistent in the environment and continue to contaminte soil and ground water. In this paper the chemical rections of the cwa diphenylarsine chloride (CLARK I), phenylarsine dichloride (PFIFFIKUS), ethylarsine dichloride (DICK) and of chlorovinyl arsenic compounds (LEWISITE) are shown. The posibilities of the detection and determination of this cwa and their metabolites are presented. 相似文献
7.
Carmen?Rossini Alexander?Bezzerides Andrés?González Maria?Eisner Thomas?EisnerEmail author 《Chemoecology》2003,13(4):199-205
Summary. Evidence is presented that pyrrolizidine alkaloid acquired
by Utetheisa ornatrix (Lepidoptera, Arctiidae) as a larva
from Crotalaria foodplants is incorporated in part into the scales
of the adult. A single forewing of a male or female moth may contain in
the order of 6 to 13 g monocrotaline in its scale cover or about 1 to 2%
of the moths systemic monocrotaline content. Based on estimates of the number
of scales per forewing, the monocrotaline content of individual scales is calculated
to be in the order of 0.1 and 0.2 ng monocrotaline per male and female scale,
respectively. This amounts to concentrations of about 1 and 3%, values roughly at
a par with the average systemic concentration (0.5-0.6%) previously determined
for monocrotaline in Utetheisa. It is argued that the presence of pyrrolizidine alkaloid
in the moths scale coating could account for the promptness with which adult Utetheisa are
rejected by spiders. It is suggested further that chemical impregnation of scales with substances
deterrent to predators may be more widespread among insects than generally assumed. 相似文献
8.
Thomas Eisner Jeffrey Conner James E. Carrel John P. McCormick Amy J. Slagle Carl Gans James C. O'Reilly 《Chemoecology》1990,1(2):57-62
Summary Frogs(Rana pipiens) fed on blister beetles (Meloidae) or cantharidin, retain cantharidin systemically. After cessation of feeding, they void the compound relatively quickly. Systemic cantharidin does not protect frogs against ectoparasitic feeding by leeches(Hirudo medicinalis) or predation by snakes(Nerodia sipedon). As suggested by our data, and from reports in the early literature, ingestion of cantharidin-containing frogs can pose a health threat to humans.Paper no. 95 of the seriesDefense Mechanisms of Arthropods; no. 94 is LaMunyon & Eisner, Psyche (in press) 相似文献
9.
若尔盖西部草甸的基本类型、特点及近几十年来的变化 总被引:7,自引:0,他引:7
2000年8月对若尔盖西部草地的调查,确定了该地18个草丛类型(不包括典型的沼泽植被)。经群丛间Pearson最大相关系数配合生境作图,将该地区的草地群丛分成3大类,即沼生草地,中生性草甸和旱生性草地。各群丛的SW指数,物种丰富度,地上生物量,裸地面积按照生境序列作图,显示中性草甸具有最高的物种丰富度和地上生物量。群丛C和J分别是沼生和旱生植被与中生性草甸之间的拐点式过渡类型,其物种丰富度明显比周期的群丛低,生境转换关键种分别为鹅绒委陵菜和垂穗披碱草。在草地物种组成上,杂类草占81.3%,莎草类仅占6.8%;群丛建群种方面,杂类草占61%,莎草类占28%;在次优势种方面,杂类草和禾草所占比重都有所增加。草原成分出现在丛中生至旱生的群丛中,在有些群丛中甚至成为次优势种。沼泽消退,黄河河道附近沙化以及过牧的阳坡山地生长带刺的旱生化植被,说明当地正经历着干旱化的过程,原因不仅有自然的还有人为的,特别是草地的过度使用。最后对当地草场的管理及发展提出了一些建议。图3表2参20 相似文献
10.