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  • 1
    Publication Date: 1994-01-18
    Print ISSN: 0027-8424
    Electronic ISSN: 1091-6490
    Topics: Biology , Medicine , Natural Sciences in General
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  • 2
    Publication Date: 1974-12-01
    Print ISSN: 0028-0836
    Electronic ISSN: 1476-4687
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Published by Springer Nature
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  • 3
    Publication Date: 1994-11-01
    Print ISSN: 0006-291X
    Electronic ISSN: 1090-2104
    Topics: Biology , Chemistry and Pharmacology , Physics
    Published by Elsevier
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  • 4
    Electronic Resource
    Electronic Resource
    Amsterdam : Elsevier
    Biochemical and Biophysical Research Communications 204 (1994), S. 1009-1015 
    ISSN: 0006-291X
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Biology , Chemistry and Pharmacology , Physics
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    [s.l.] : Nature Publishing Group
    Nature 252 (1974), S. 711-713 
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] Various tests have been described to study this penetration: the post coital test provides an estimate of the spermatozoa penetration in vivo but only allows a very incomplete appreciation of migration intensity and of movement quality. In vitro tests enable a dynamic study of spermatozoa ...
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  • 6
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Gamete Research 9 (1984), S. 183-195 
    ISSN: 0148-7280
    Keywords: flagellar wave ; human spermatozoa ; microcinematography ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Microcinematographic analysis (50 frames/sec) of the movement of 57 ejaculated human spermatozoa showed a heterogeneity of the flagellar parameters (velocity of the wave development (Vd), velocity of the wave propagation (Vc), beat frequency) corresponding to that of head trajectories (progressive velocity and amplitude of the lateral head displacement). According to our results the interdoublet sliding velocity might control the progressive velocity of the spermatozoa through the wave propagation velocity. The presence of the principal bend on the proximal part of the flagellum (20 μm) might inhibit the initiation of a new wave. The complex relation existing between Vc and Vd seems to indicate that the two velocities are partly independent of one another.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
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  • 7
    ISSN: 0148-7280
    Keywords: sperm ; human ; sperm motility ; kinematics ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Tracks of 30 progressively motile washed human spermatozoa were plotted manually from 200-Hz frame rate video recordings. Tracks at 100, 66.7, 50, 40, 33.3., 25, 20, 10, and 5 Hz were then constructed using every 2nd, 3rd, 4th, 5th, 6th, 8th, 10th, 20th, or 40th point. The 200-Hz tracks were analyzed by traditional manual methods, and all ten sets of tracks analyzed using a computer-assisted method (“Videomot,” developed originally to analyze 30-Hz tracks) to eliminate observer bias. Progression velocity (VSL) remained constant under all analysis conditions. Average path velocity (VAP) also remained essentially constant, although Videomot was less reliable at high frame rates due to problems in determining the average path. Curvilinear velocity (VCL) was very frame rate dependent (the 25-Hz mean value was only 56.5% of that at 200 Hz), and Videomot was more accurate than manual analysis at 200 Hz. Values of the amplitude of lateral head displacement (ALH) were acceptable at most frame rates. At 〈 66.7 Hz the inclusion of spurious curvilinear track deviations caused lower mean ALH values, and at 5 Hz ALH could not be measured since the track was essentially the average path. Beat/cross frequency (BCF) was also frame rate dependent; at high rates there was the same problem as with ALH measurements, while at ≤ 25 Hz the maximum BCF was restricted by the frame rate. We conclude that human sperm movement characteristics can be measured at frame rates ca. 30 Hz but only if the constraints affecting VCL and BCF values are understood and accepted. Finally, 〈 10 Hz can only give values for VSL and, perhaps, VAP.
    Additional Material: 7 Ill.
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  • 8
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Gamete Research 4 (1981), S. 83-95 
    ISSN: 0148-7280
    Keywords: human spermatozoa ; flagellum ; motion ; microcinematography ; kinematics ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: A microcinematographic (50 f/s) study was performed on motile human spermatozoa. Eighty percent were found to have a linear trajectory and a pseudo-sinusoidal head displacement pattern. Throughout their progression, the spermatozoa periodically rotated on their longitudinal axis at a frequency equal to that of flagellar wave formation. These waves were found always to begin on the same side of the cell and to propagate in the flattened plane of the head until the moment of rotation. At this time the wave had reached a point near the middle of the flagellum. Beyond this point, the flagellum moves out of the plane of the head. Different variables used to characterize the movement of spermatozoa included the velocity of progression, amplitude and velocity of head displacement, frequency of rotation, wave amplitude, and propagation velocity of the flagellar wave. Among these variables, it was the propagation velocity of the wave that was found to be best correlated with the velocity of spermatozoan progression. This flagellar wave exhibited two stages, one of initiation and one of propagation.
    Additional Material: 7 Ill.
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  • 9
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Molecular Reproduction and Development 29 (1991), S. 157-162 
    ISSN: 1040-452X
    Keywords: Sperm ; Motility ; Flagella ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The aim of this work was to study the role of different parameters involved in the motility of human spermatozoa. Human spermatozoa were totally demembranated with 0.05% Triton X-100, and the demembranation was checked using electron microscopy. We have shown that, with a concentration of ATP-Mg lower than 2 mM, a pH effect was observed with a dose-dependent motility reactivation at pH 7.1, with 14% ± 2.0% motile cells at 1 mM ATP-Mg and a straight line velocity (VSL) of 12.0 ± 1.4 μm/sec. However, at pH 7.8, more than 65% of the spermatozoa were reactivated with as low as 0.02 mM ATP-Mg and 77.8% ± 2.5% of them were motile at 1 mM ATP-Mg and had a VSL of 23.4 ± 3.9 μm/sec. The depletion of free calcium by the addition of 0.5 mM EGTA in the reactivation medium (RM) improved the percentage of motile cells and the VSL most markedly at low ATP-Mg and low pH. If no MgSO4 was added in RM, cells were not motile at pH 7.8, but 30-40% reactivated at pH 7.1. If 5 mM Ca2+ was added to the RM, up to 88% of the cells became reactivated at both pHs, but the beat frequencies were very low, suggesting different mechanisms of reactivation when Mg2+ or when Ca2+ is present in the RM.
    Additional Material: 2 Ill.
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  • 10
    ISSN: 0148-7280
    Keywords: fertilization ; postacrosomal sheath ; sperm ; zona-free hamster egg penetration ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: We selected 17 infertile men whose sperm ultrastructural study revealed at least 70% of spermatozoa with postacrosomal sheath (PAS) anomalies. Among the other sperm head defects, those affecting the nuclear shape were most frequently encountered and were highly correlated with PAS anomalies (r = +0.71; P 〈 .01). PAS anomalies were also correlated with chromatin condensation defects (r = +0.67; P 〈 .01) and acrosome anomalies (r = +0.53; P 〈.05). Those spermatozoa were tested for their ability to penetrate zona-free hamster oocytes and were compared to a control sperm population. It was shown that sperm head morphological anomalies impaired the ability of spermatozoa to attach to and penetrate the oocyte. The highest significant and negative correlations were found between the penetration rate and 1) the percentage of spermatozoa with PAS anomalies (r = -0.81; P 〈 .01) and 2) the percentage of spermatozoa with nuclear shape anomalies (r = -0.66; P 〈 .01). The effect of PAS anomalies on human fertilization process are discussed.
    Additional Material: 8 Ill.
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