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791.
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Oliver Gastmann Peter Burfeind Eberhard Güunther Horst Hameister Claude Szpirer Sigrid Hoyer-Fender 《Molecular reproduction and development》1993,36(4):407-418
Outer dense fibers (ODFs) are located on the outside of the axoneme in the midpiece and principal piece of the mammalian sperm tail and may help to maintain the passive elastic structures and elastic recoil of the sperm tail. We have identified and describe here a human gene that is homologous to the Mst(3)CGP gene family of Drosophila melanogaster and encodes an ODF protein of 241 amino acids. The transcribed region has a size of ?lkb and contains two exons of 416 bp and 406 bp, respectively, not including the 3′ untranslated region. The gene is expressed in testis but not in human spleen, kidney, or brain and resembles in this respect the expression of the Drosophila Mst(3)CGP gene family in the male germline. An antiserum raised against a synthetic peptide derived from the N-terminus of the encoded sequence identified a protein of ? 32 kDa in an extract of human sperm flagella. By Southern-blot analyses and in situ hybridization, the ODF gene was localized to band q22 of chromosome 8. The isolation of a human gene encoding a sperm tail protein may provide the ability to identify and investigate, on the molecular level, possible reasons for human male infertility that are dependent on flagellar disturbances. © 1993 Wiley-Liss, Inc. 相似文献
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Six infant squirrel monkeys were reared in social isolation. They responded differentially to playbacks of two species-specific alarm calls. The reaction to the alarm peep, the warning call to bird predators, was a prompt flight to the mother surrogate and essentially resembled the respective behavior of mother-reared infants. The responses to yapping, the alarm call to terrestrial predators, were less clear-cut and habituated soon. However, when yapping was played back in connection with the presentation of a reference object, both subjects tested in this way clearly avoided the object and preferred contact with the mother surrogate while they thoroughly explored an object presented with a control tone. From this it can be concluded that the perception of both alarm calls is innate. In addition, the method of behavior-contingent playback of vocalizations simulates the learning process by which the visual perception of terrestrial predators of the habitat is acquired. 相似文献
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799.
Sigrid Hopf 《International journal of primatology》1981,2(4):335-349
This paper deals with the functioning and malfunctioning of maternal behavior in relation to external and social conditions.
During developmental studies in captive squirrel monkey groups, 49 mother-infant pairs were observed. There were several cases
of maternal inadequacy subsequent to (1) postnatal transportation, (2) exaggerated social investigation by immatures,and (3) premature allomothering. Brief mother-infant separations by humans did not yield such failures. One female consistently
prevented nursing with at least three of her five viable offspring. Complete or partial failure of maternal behavior did not
preclude subsequent recovery and/or adequate allomothering.
Dedicated to Prof. Dr. Med. Detlev Ploog on the occasion of his 60th birthday. 相似文献
800.
The Function of Homoglutathione and Hydroxymethylglutathione for the Scavenging of Hydrogen Peroxide 总被引:2,自引:0,他引:2
The function of homoglutathione ( 相似文献