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801.
ABSTRACT. The neuromuscular junctions of abdominal body wall muscles of larval Lucilia sericata are mainly superficial, with no glial sheath, and are surrounded by a well-developed subsynaptic reticulum. Injection of l -glutamate into the haemolymph of adult male Locusta migratoria and larvae of Lucilia sericata caused reversible effects on motor activity. These effects were quantified and dose—response curves are presented. The effective concentration of the injected doses is low enough to be physiologically relevant. Injection of l -aspartate into Locusta haemolymph affected motor activity. Injection of l -aspartate into Lucilia larvae produced no detectable effect. Injections combining l -aspartate and l -glutamate into Lucilia larvae had a synergistic effect on the duration of paralysis, compared with the same concentration of l -glutamate injected alone. 相似文献
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803.
Suspension cultures of Hevea brasiliensis cells can metabolizethe growth regulator 2-chloroethylphosphonic acid to producea number of compounds, one of which appears to be an acid-labileconjugate. The general metabolic pattern closely resembles thatfound previously using Hevea leaves. Evidence that the compoundsformed are not chromatographic artefacts of a type describedby other authors is presented. 相似文献
804.
BATIDO AND OTHER GUATEMALAN BEVERAGES PREPARED FROM CACAO 总被引:1,自引:0,他引:1
WILSON POPENOE 《American anthropologist》1919,21(4):403-409
805.
ADRIAN A. BARNETT SARAH A. BOYLE MARILYN M. NORCONK SUZANNE PALMINTERI RICARDO R. SANTOS LIZA M. VEIGA THIAGO H.G. ALVIM MARK BOWLER JANICE CHISM ANTHONY DI FIORE EDUARDO FERNANDEZ‐DUQUE ANA C. P. GUIMARÃES AMY HARRISON‐LEVINE TORBJØRN HAUGAASEN SHAWN LEHMAN KATHERINE C. MACKINNON FABIANO R. DE MELO LEANDRO S. MOREIRA VIVIANE S. MOURA CARSON R. PHILLIPS LILIAM P. PINTO MARCIO PORT‐CARVALHO ELEONORE Z. F. SETZ CHRISTOPHER SHAFFER LÍVIA RODRIGUES DA SILVA SULEIMA DO S. B. DA SILVA RAFAELA F. SOARES CYNTHIA L. THOMPSON TATIANA M. VIEIRA ARIOENE VREEDZAAM SUZANNE E. WALKER‐PACHECO WILSON R. SPIRONELLO ANN MACLARNON STEPHEN F. FERRARI 《American journal of primatology》2012,74(12):1106-1127
Neotropical monkeys of the genera Cacajao, Chiropotes, and Pithecia (Pitheciidae) are considered to be highly arboreal, spending most of their time feeding and traveling in the upper canopy. Until now, the use of terrestrial substrates has not been analyzed in detail in this group. Here, we review the frequency of terrestrial use among pitheciin taxa to determine the ecological and social conditions that might lead to such behavior. We collated published and unpublished data from 14 taxa in the three genera. Data were gleaned from 53 published studies (including five on multiple pitheciin genera) and personal communications of unpublished data distributed across 31 localities. Terrestrial activity was reported in 61% of Pithecia field studies (11 of 18), in 34% of Chiropotes studies (10 of 29), and 36% of Cacajao studies (4 of 11). Within Pithecia, terrestrial behavior was more frequently reported in smaller species (e.g. P. pithecia) that are vertical clingers and leapers and make extensive use of the understory than in in the larger bodied canopy dwellers of the western Amazon (e.g. P. irrorata). Terrestrial behavior in Pithecia also occurred more frequently and lasted longer than in Cacajao or Chiropotes. An apparent association was found between flooded habitats and terrestrial activity and there is evidence of the development of a “local pattern” of terrestrial use in some populations. Seasonal fruit availability also may stimulate terrestrial behavior. Individuals also descended to the ground when visiting mineral licks, escaping predators, and responding to accidents such as a dropped infant. Overall, the results of this review emphasize that terrestrial use is rare among the pitheciins in general and is usually associated with the exploitation of specific resources or habitat types. Am. J. Primatol. 74:1106‐1127, 2012. © 2012 Wiley Periodicals, Inc. 相似文献
806.
WILSON J. E. M. COSTA 《Zoological Journal of the Linnean Society》2008,153(1):147-160
A phylogenetic analysis based on morphological characters indicates that Leptolebias Myers, 1952, a genus of small killifishes highly threatened with extinction, from Brazil, is paraphyletic. As a consequence, Leptolebias is restricted in this study to a well‐supported clade that includes Leptolebias marmoratus (Ladiges, 1934), Leptolebias splendens (Myers, 1942), Leptolebias opalescens (Myers, 1942), and Leptolebias citrinipinnis ( Costa, Lacerda & Tanizaki, 1988 ), from the coastal plains of Rio de Janeiro, and Leptolebias aureoguttatus ( Cruz, 1974 ) (herein redescribed, and for which a lectotype is designated) and Leptolebias itanhaensis sp. nov. , from the coastal plains of São Paulo and Paraná, in southern Brazil.Leptolebias is diagnosed by three synapomorphies: a caudal fin that is longer than deep, a single anterior supraorbital neuromast, and dark pigmentation that does not extend to the distal portion of the dorsal fin in males. A key is provided for the identification of species of Leptolebias. Three species formerly placed in Leptolebias, Leptolebias minimus (Myers, 1942), Leptolebias fractifasciatus ( Costa, 1988 ), and Leptolebias cruzi ( Costa, 1988 ), are transferred to Notholebias gen. nov. , which is hypothesized to be the sister group to the clade comprising Leptolebias, Campellolebias Vaz‐Ferreira & Sierra, 1974, and Cynopoecilus Regan, 1912. Notholebias gen nov. is diagnosed by two synapomorphies: a narrow basihyal and the presence of iridescent bars on the caudal fin in males; and three features interpreted as plesiomorphic, but not occurring in Leptolebias, Campellolebias, or Cynopoecilus, the presence of dermosphenotic, well‐developed contact organs on the pectoral fin in males, and an opercular region with red bars in males. ‘Leptolebias’leitaoi, a species from Bahia, in north‐eastern Brazil, is considered as having an uncertain phylogenetic position, as all known preserved material is presently lost, and the species may be extinct. © 2008 The Linnean Society of London, Zoological Journal of the Linnean Society, 2008, 153 , 147–160. 相似文献
807.
SYNOPSIS. Of several methods developed for cryopreservation of Trypanosoma vivax, Trypanosoma congolense , and Trypanosoma brucei metacyclic forms in tsetse fly organs, as well as bloodstream forms in host blood, one proved the most satisfactory. In this method, infected fly proboscises and salivary glands were placed in glass capillary tubes containing fetal calf serum with 8% (v/v) glycerol as the cryoprotectant. The method for bloodstream forms involved the addition of glycerol directly to infected blood, which was then dispensed into capillary tubes. Next the tubes were placed in paper containers inside a glass test tube with a 5 mm thick plasticine jacket. The insulated assembly was suspended in the liquid nitrogen vapor phase in an LR-35 (Union Carbide) refrigerator for 45 min. Under these conditions, the cooling rate was 2 C/min. The frozen samples were transferred to permanent storage. The viability and infectivity of the preserved organisms were found to be satisfactory upon testing, and no antigenic changes were observed. Laboratory and field applications of the method are discussed. 相似文献
808.
809.
810.
H. CLYDE WILSON 《American anthropologist》1958,60(6):1193-1196