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Phillip S. Lobel 《Environmental Biology of Fishes》1992,33(4):351-358
Synopsis Low frequency sounds are shown to be associated with the spawning of two Caribbean coral reef fishes: the hamlet, Hypoplectrus unicolor (Serranidae) and the striped parrotfish, Scarus iserti (Scaridae). Both fishes produce distinctive sounds while broadcasting gametes in midwater. H. unicolor produces sounds via muscle stimulation of the swimbladder. Fin movements among group spawning S. iserti produce hydrodynamic noise. Although reproductive behaviors of these two species have been previously studied in detail,
the association of sounds with mating is new. The mating sounds cannot be easily detected by human hearing underwater but
are recordable using a hydrophone. The sounds are distinct and recognizable enough to allow counting and acoustic mapping
of mating events in these species. 相似文献
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In humans, a deficiency of the lysosomal hydrolase α-
-iduronidase (IDUA; EC 3.2.1.76) results in the lysosomal storage of the glycosaminoglycans heparan sulfate and dermatan sulfate, thereby causing the lysosomal storage disorder mucopolysaccharidosis type I. The gene for IDUA is split into 14 exons spanning approximately 19 kb. We report the sequence of two noncontiguous segments of the IDUA gene, one 1.8-kb segment containing exons 1 and 2 and surrounding sequences and a second segment of 4.5 kb containing the last 12 exons. The potential promoter for IDUA has only GC box type consensus sequences consistent with a housekeeping promoter and is bounded by an Alu repeat sequence. The first two exons of IDUA are separated by an intron of 566 bp, then there is a large intron of approximately 13 kb, and the last 12 exons are clustered within 4.5 kb. No consensus polyadenylation signal was found in the 3′ untranslated region, although two variant polyadenylation signals are proposed. 相似文献
25.
Gerard H. Markx Christopher L. Davey Douglas B. Kell Phillip Morris 《Journal of biotechnology》1991,20(3):279-290
A novel technique is described for the measurement of the volume fraction of biomass in a suspension by the simultaneous measurement of the conductivity of a suspension containing cells and of the medium in which the cells are suspended. The presence of non-conducting particulate matter in a suspension will cause the conductivity of a suspension to be decreased relative to that of the medium in which the particles are suspended. A simple equation (the Bruggeman equation) describes the relationship between the volume fraction of non-conducting particulate matter and the decrease in conductivity. The accuracy of this method for the determination of the biomass concentration of plant cells (Festuca arundinacea) in culture was shown. The method was successfully applied to the on-line determination of biomass concentrations during the growth of F. arundinacea cultures, and gave good agreement with biomass levels as determined from measurements of the radio-frequency dielectric permittivity of such cultures. 相似文献
26.
Phillip V. Tobias 《International Journal of Anthropology》1991,6(3):277-280
Having been approached from time to time by various museum, university and governmental authorities in Australia, California
and Scotland, I have set down some brief notes on the scientific, medical, dental and educational importance and value of
collections of recent human skeletons drawn from populations in all parts of the world.
This article does not pretend to completeness. It has been set down in the hope that it may be of assistance to those officiers
in charge of such collections and who may be pondering upon the worthwhileness of such collections being retained and maintained. 相似文献
27.
Quantitation, with a new assay, of Theiler''s virus capsid protein in the central nervous system of mice. 总被引:6,自引:6,他引:0 下载免费PDF全文
We developed a quantitative assay for antigens at the single-cell level. Tissue sections were reacted with a primary antibody, a biotinylated secondary antibody, or 35S-streptavidin. Binding of streptavidin to cells was quantitated by microscopic autoradiography. We showed that the number of autoradiographic grains was proportional to the amount of antigen per cell. With this assay, we studied the synthesis of Theiler's virus capsid proteins VP1, VP2, and VP3 in permissive BHK cells grown in vitro and in mouse central nervous system (CNS) cells during a persistent infection. We found that synthesis of the three capsid proteins was restricted in mouse CNS cells. Restricted virus replication could play a major role in the persistence of Theiler's virus in mouse CNS cells. 相似文献
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Christopher E. Taylor Philip W. Stashak George Caldes Benjamin Prescott B.J. Fowlkes Phillip J. Baker 《Cellular immunology》1984,83(1):26-33
Several lectins were tested for their capacity to alter the antibody response to type III pneumococcal polysaccharide (SSS-III). The antibody response was enhanced by concanavalin A (Con A), phytohemagglutinin (PHA), as well as lectins from Phytolacca americana (Pa-2), Pisum sativum (PSA), and Lens culinaris (LCH), when these lectins were given 2 days after immunization with SSS-III; however, suppression was obtained when Con A and Pa-2 were given at the time of immunization. By contrast the lectins from Vicia villosa (VVL) and Bauhinia purpurea (BPA) did not alter the antibody response. Since the lectins PSA and LCH bind to the same monosaccharide as Con A, whereas the other lectins bind to different monosaccharides, these findings indicate that there is no relationship between nominal monosaccharide specificity and the capacity to modulate the antibody response. Substantial increases in the magnitude of the IgG1 antibody response was noted after the administration of Con A whereas profound enhancement of IgG2a antibody response was noted after PHA was given. 相似文献