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A Pye 《Journal of morphology》1966,118(4):495-510
The structure of the ears, especially of the cochleae, has been examined in two superfamilies, i.e. Emballonuroidea and Rhinolophoidea of the Microchiroptera. An intra-vitam fixation method was used and gave good histological preparations. The following features of the cochlea have been measured: the general size of the cochlea, the width and thickness of the basilar membrane, the size of the spiral ligament and the height of the cells of Claudius. The interpretation of measurements is discussed in relation to the nature of ultrasonic sounds produced by bats. It is concluded that functional interpretation of specific cochlear modifications cannot be assessed at present. 相似文献
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Various measurements have been made on the cochleae of some insectivorous African Microchiroptera, including representatives from all the three superfamilies, the Emballonuroidea, Rhinolophoidea and Vespertilionoidea. Their ultrasonic pulses have been recorded and correlations between the structure of the cochlea and the pulses have been attempted. The most extreme measurements are found in the Rhinolophoidea, confirming earlier results in other species. 相似文献
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Scott C. Pedersen 《Journal of morphology》1993,218(1):85-98
This study suggests that the evoution of head posture is bats is constrained by the demands of vocalization during echolocation. Nasalemitting microchiropteran taxa are easily identified by their characteristic rotation of the basicranium ventrally about the cervical axis, the depression of the rostrum below the basicranial axis, and by the rotation of the lateral semicircular canals so as to maintain their horizontal orientation during flighrt. The converse is true for oral-emitting Microchiroptera. The general form of the microchiropteran skull has been canalized along two distinct evolutionary paths, respectively, towards oral-emitting or nasal-emitting forms. © 1993 Wiley-Liss, Inc. 相似文献
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The structure of the cochlea has been studied in 26 species of feral rodents from the Sub-Orders Myomorpha and Caviomorpha. The specimens were all intravitally perfused to obtain good preservation of the internal ear. The following measurements were made on the cochleae: the height and width of the cochlea, the number of half-turns, the width and thickness of the basilar membrane, the height of the cells of Claudius and the size of the spiral ligament; other special features were also noted. 相似文献
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The hemoglobin of the Indian false vampire Megaderma lyra contains only one component. In this paper, we are presenting its primary structure. The globin chains were separated by high-performance liquid chromatography and the sequences determined by automatic liquid and gas phase Edman degradation of the chains and their tryptic peptides, as well as of the prolyl-peptides obtained by acid hydrolysis of the Asp-Pro bond in the alpha- and beta-chains. The alpha-chains show 23 and the beta-chains 20 exchanges compared with the human alpha- and beta-chains, respectively. In the alpha-chains, three exchanges involved alpha 1/beta 1 contacts. In the beta-chains one heme-and three alpha 1/beta 1 contacts are exchanged. The functional and systematic aspects of these replacements are discussed. 相似文献
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G A Singer T Kleinschmidt J D Pettigrew G Braunitzer 《Biological chemistry Hoppe-Seyler》1991,372(12):1089-1095
The Australian ghost bat (Macroderma gigas, Microchiroptera) has two hemoglobin components in the ratio 3:2. They share identical beta-chains and differ by three replacements in the alpha-chains. The primary structures of all three chains are presented. They could be separated by high-performance liquid chromatography. The sequences were determined by automatic liquid and gas phase Edman degradation of the chains and their tryptic peptides. The two alpha-chains show 18 and 19 and the beta-chains 15 exchanges compared to human alpha- and beta-chains, respectively. The divergent evolution of Macroderma gigas and Megaderma lyra, two representatives of the family Megadermatidae, is discussed. An influence of replacements at functionally important positions on the hemoglobin oxygen affinity seems unlikely. 相似文献
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N B Cooper V F Allison J E Ubelaker 《Zeitschrift für Parasitenkunde (Berlin, Germany)》1975,46(3):229-239
Transmission electron microscopy of the scolex of the 8-day-old Hymenolepis diminuta cysticercoid demonstrates its resemblance to the scolex of the adult. A syncytial tegument composed of external and internal layers is connected by cytoplasmic extensions. Fully developed microtriches are present. Furthermore, a basement membrane, muscle layers, and medullary region containing flame cells, nerve tissue, and other cell bodies are observed. Of particular interest is the presence of discrete sensory endings whose function is discussed. 相似文献
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Studies of the properties of copolymers of N-carboxy sarcosine anhydride with other N-carboxy α-amino acid anhydrides have shown that the secondary structure may be a function of the type of initiator used. In particular, when polysarcosine is the initiator, and the “chain effect” becomes possible, blocklike character appears in the copolymer. This is the result of selective and rapid polymerization of N-unsubstituted N-carboxy α-amino acid anhydrides by the chain-effect mechanism. In suitable circumstances, therefore, the latter may be used to induce order into copolymerizations of this type. 相似文献
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Torula graminis produced blastoconidia in acropetalous chains after the evagination of a characteristic conidiogenous cell. Conidia consisted of up to 15 cells and their cell wall was differentiated into an outer melanized zone and an inner hyaline zone. A consistent cytoplasmic feature of conidial cells was the presence of dictyosomal-like membranous stacks often closely associated with the nucleus. Vesicles that developed from the dictyosomal-like cisternae were probably involved in conidial wall synthesis. 相似文献
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