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  • 1
    Electronic Resource
    Electronic Resource
    Characteristics of Sperm Motility (1991)
    Oxford, UK : Blackwell Publishing Ltd
    Annals of the New York Academy of Sciences 637 (1991), S. 0 
    Details
    ISSN: 1749-6632
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Natural Sciences in General
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1749-6632.1991.tb27326.x
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  • 2
    Electronic Resource
    Electronic Resource
    Early Indicators of Male Reproductive Toxicity (1988)
    Oxford, UK : Blackwell Publishing Ltd
    Risk analysis 8 (1988), S. 0 
    Details
    ISSN: 1539-6924
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Energy, Environment Protection, Nuclear Power Engineering
    Notes: Longitudinal data were analyzed for seminal characteristics of rhesus monkeys and beagles. The monkeys were exposed to DBCP; the beagles were exposed to acute or chronic whole body gamma irradiation. The semen was analyzed for volume and sperm concentration. Sperm were measured for percent motility, swimming speed, and head dimensions. Abnormalities of the sperm tail were also noted. All treatments resulted in measurable effects on the semen parameters. Sperm production, as evaluated by seminal sperm concentration or total sperm numbers in the ejaculate, was as informative of testicular toxicity as any other parameter or combination of parameters. A consistent finding was that changes in sperm output occurred concomitantly with changes in sperm motility.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1539-6924.1988.tb01150.x
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  • 3
    Electronic Resource
    Electronic Resource
    Calibration and error analysis of a new magnetic sphere microrheometer (1994)
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 65 (1994), S. 3268-3275 
    Details
    ISSN: 1089-7623
    Source: AIP Digital Archive
    Topics: Physics , Electrical Engineering, Measurement and Control Technology
    Notes: A magnetic microrheometer has been built, which can be used to study the rheological properties of materials that are available in small volumes and have distinct phases. The instrument performs creep tests (displacement in response to an imposed force), using magnetic microspheres of diameter 7 μm and larger. Displacement histories of the spheres are video-recorded and analyzed, with high resolution, using computer vision methods. In this article, results are presented for the magnetic force calibration and for a test using a Newtonian fluid to evaluate the performance of the instrument. A comprehensive analysis of the different sources of error in measuring Newtonian fluid viscosities was performed, resulting in quantitative delineation of the accuracy and precision of the microrheometer.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1144561
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  • 4
    Electronic Resource
    Electronic Resource
    Structure of the cumulus matrix and zona pellucida in the golden hamster: A new view of sperm interaction with oocyte-associated extracellular matrices (1988)
    Springer
    Cell & tissue research 251 (1988), S. 555-564 
    Details
    ISSN: 1432-0878
    Keywords: Cumulus ; Zona pellucida ; Extracellular matrix ; Sperm ; Fertilization ; Golden hamster
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Hamster oocyte-cumulus complexes (OCC), with and without sperm, were structurally analyzed by light- and electron microscopy using freeze substitution. This method has yielded a clear picture of the extracellular oocyte investments, the cumulus cell matrix and the zona pellucida. The cumulus matrix has an overall homogeneous fibrillar structure which appears to attach to cumulus cells at their filopodial extensions. The matrix also extends into the outer regions of the zona pellucida. The zona pellucida has a distinct porous configuration throughout its entire structure. During gamete interaction experiments, capacitated hamster sperm with ultrastructurally intact acrosomes were found throughout the matrix. Sperm had dramatic effects on the matrix, resulting in compression and stretching. Sperm found on the zona pellucida had initiated or completed the acrosome reaction. During the initial stages of the acrosome reaction, the matrix was in contact with the sperm. At later stages of the acrosome reaction, there was a complete loss of matrix material in regions near the sperm.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00214003
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  • 5
    Electronic Resource
    Electronic Resource
    The evolution of hamster sperm motility during capacitation and interaction with the ovum vestments in vitro (1986)
    New York, NY : Wiley-Blackwell
    Gamete Research 14 (1986), S. 333-346 
    Details
    ISSN: 0148-7280
    Keywords: spermatozoon ; motility ; capacitation ; hamster ; fertilization ; acrosome reaction ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Movement characteristics of golden hamster spermatozoa were studied upon collection from the cauda epididymis, during an incubation which capacitates the spermatozoa in vitro, during penetration of the cumulus, and during attachment to and penetration of the zona pellucida. High-speed videomicrography was employed to quantitate flagellar beat frequency and shape. The status of the acrosome was also assessed. During capacitation, hamster spermatozoa become increasingly invigorated before the onset of hyperactivated motility. Within the cumulus, beat frequency and curvature are reduced, apparently in response to the physical resistive properties of the matrix material. These properties appear to vary within the cumulus. Initial attachment to the zona precedes completion of the acrosome reaction, is non-rigid, and is accompanied by increased beat frequency and curvature. Subsequently, the onset of rigid binding to the zona, completion of the acrosome reaction, and increased flagellar beat frequency are very closely associated in time. The latter produces an increase in thrust against the zona. Preliminary results indicate that ensuing zona penetration requires not more than five minutes, is at oblique angles, and is associated with a continuation of vigorous flagellar beating.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/mrd.1120140406
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  • 6
    Electronic Resource
    Electronic Resource
    Changes in motility that accompany the acrosome reaction in hyperactivated hamster spermatozoa (1984)
    New York, NY : Wiley-Blackwell
    Gamete Research 10 (1984), S. 253-265 
    Details
    ISSN: 0148-7280
    Keywords: sperm motility ; hyperactivation ; acrosome reaction ; spermatozoa ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: High-speed videomicrography was used to compare the movement characteristics of hamster epididymal sperm which completed the acrosome reaction in vitro with those of unreacted sperm in the same sample. More than 90% of the motile sperm incubated for 4.25 hr in a modified Tyrode's medium containing bovine serum albumin, taurine, and epinephrine were hyperactivated and about half were acrosome reacted. The flagella of reacted sperm beat with significantly lower frequency and bent into more acute curves than those of unreacted sperm. Lowered beat frequencies were not attributable to aging, because sperm induced to react synchronously at 3.5 hr using lysophosphatidyl choline beat with similar lowered frequencies. Both acrosome-reacted and unreacted hyperactivated sperm swam in circular trajectories resulting from asymmetrical flagellar beating. The flagellar beating of unreacted sperm was more symmetrical; consequently, they swam in larger circles and had the potential to cover space more rapidly. Some unreacted sperm, perhaps in transition towards hyperactivation, swam in helical trajectories.When preincubated sperm were added to slides containing oocytes in cumulus, some unreacted sperm initiated cumulus penetration. All reacted sperm failed to do so, adhering instead to the cumulus at its boundary. Reacted sperm attached to the zonae pellucidae of cumulus-free oocytes via the region of the inner acrosomal membrane. Unreacted sperm attached via the equatorial region, but pivoted about the point of attachment, thus failing to generate sustained thrust against the zona. In conclusion, unreacted hyperactivated sperm have a different potential than reacted sperm for movement and interaction with egg vestments.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/mrd.1120100305
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  • 7
    Electronic Resource
    Electronic Resource
    Movement of cynomolgus and rhesus monkey spermatozoa collected from the lower female reproductive tract (1989)
    New York, NY : Wiley-Blackwell
    Gamete Research 24 (1989), S. 333-342 
    Details
    ISSN: 0148-7280
    Keywords: cervical mucus ; motility of sperm ; hyperactivation of sperm ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Postcoital (pc) cervical mucus was collected in 73 menstrual cycles of cynomolgus monkeys and in 43 cycles of rhesus monkeys at 2,6,10,30 hr pc. Videomicrography was used to analyze sperm numbers and movement in the mucus. Both cynomolgus and rhesus monkeys had comparable populations of motile sperm in the mucus at 2 hr pc. However, by 6 hr pc, cervical mucus from cynomolgus monkeys contained twice as many total sperm and motile sperm as mucus from rhesus monkeys (P 〈.05). Mean swimming speeds of the free-swimming cervical sperm were similar for the two species at this time. No motile sperm were recovered in mucus from rhesus monkeys at 30 hr pc. In cynomolgus monkeys, however, 14 of the 26 animals examined at 30 hr pc had motile sperm in their mucus. These sperm exhibited lower percent molility, percent free-swimming sperm, and swimming speed than those sperm observed at 6 hr pc. Uterine sperm were collected by transcervical or transuterine aspiration from cynomolgus monkeys. In the transcervical technique, sperm were successfully obtained in four of nine animals examined at 6 hr and in four of five animals at 30 hr pc. The percentage of motile sperm in the uterine fluid was high, 82% ± 4%, and the swimming speeds (86 ± 2μm/sec) were higher than those observed in cervical mucus. Approximately 5-10% of the uterine sperm exhibited swimming motions similar to the hyperactivated motility seen in most mammals. These findings indicate that the sperm cervical mucus interaction in vivo in cynomolgus monkeys has more similarities to the human situation than does the interaction in rhesus monkeys.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/mrd.1120240309
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  • 8
    Electronic Resource
    Electronic Resource
    Factors regulating mammalian sperm migration through the female reproductive tract and oocyte vestments (1989)
    New York, NY : Wiley-Blackwell
    Gamete Research 22 (1989), S. 443-469 
    Details
    ISSN: 0148-7280
    Keywords: sperm ; transport ; mucus ; cumulus ; zona pellucida ; fertilization ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Mechanisms of mammalian sperm migration through the female reproductive tract and ovum vestments are described. The perspective is biophysical as well as biochemical and morphological, and the focus is upon the role of sperm motility in these processes. Sperm forward progression is characterized as an interactive process between the the cell and its environment, and the mediation of flagellar bend propagation by the physical properties of its surroundings is described. These properties, together with flagellar beat kinematics, sperm morphology, and surface properties, determine the magnitude of the forces generated by sperm and their consequent rate of progression. Sperm interactions with the cervical mucus, the cumulus oophorus, and the zona pellucida are described. The poorly understood affinity of the sperm surface for the macromolecules of the mucus, cumulus, and zona is stressed, as is the viscoelastic structural mechanical resistance of these biopolymers to sperm motion. The kinematics and consequences of hyperactivated sperm motion are presented, with emphasis on objective characterization of such motion (as a biomarker), along with analysis of the mechanical advantage that such motion may confer on spermatozoa during egg-vestment interaction.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/mrd.1120220410
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  • 9
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    Design of a Semisolid Vaginal Microbicide Gel by Relating Composition to Properties and Performance (2010)
    Springer
    Details
    Publication Date: 2010-09-15
    Print ISSN: 0724-8741
    Electronic ISSN: 1573-904X
    Topics: Chemistry and Pharmacology
    Published by Springer
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  • 10
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    Measuring Macrodiffusion Coefficients in Microbicide Hydrogels via Postphotoactivation Scanning (2008)
    American Chemical Society
    Details
    Publication Date: 2008-02-01
    Print ISSN: 1525-7797
    Electronic ISSN: 1526-4602
    Topics: Chemistry and Pharmacology
    Published by American Chemical Society
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