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  • General Chemistry  (7,237)
  • Cell & Developmental Biology  (2,067)
  • Seismicity
  • 1975-1979  (5,879)
  • 1935-1939  (3,533)
Collection
Years
Year
  • 1
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    In:  Geophys. J. R. astr. Soc., Warszawa, Bundesanstalt für Geowissenschaften und Rohstoffe, vol. 57, no. 1, pp. 537-555, pp. 2121
    Publication Date: 1979
    Keywords: Subduction zone ; Seismicity ; Seismology ; South ; America ; GJRaS
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  • 2
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    In:  J. Geophys. Res., Luxembourg, Conseil de l'Europe, vol. 83, no. 11, pp. 2825-2838, pp. 1078, (ISBN: 0-12-018847-3)
    Publication Date: 1979
    Keywords: Subduction zone ; Seismicity ; Fault plane solution, focal mechanism ; JGR
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  • 3
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    In:  J. Geophys. Res., London, Army Corps of Engineers, Woodward-Clyde Consultants, vol. 84, no. B9, pp. 4583-4591, pp. 1013, (ISBN: 0-12-018847-3)
    Publication Date: 1979
    Keywords: Seismicity ; Subduction zone ; Volcanology ; JGR
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  • 4
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    In:  J. Geophys. Res., Luxembourg, Conseil de l'Europe, vol. 84, no. 7055, pp. 2235-2242, pp. B05S07, (ISBN: 0534351875, 2nd edition)
    Publication Date: 1979
    Keywords: Seismicity ; SModelling ; Tectonics ; Stress ; Strong motions ; Earthquake hazard ; JGR
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  • 5
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    In:  Geophys. J. R. astr. Soc., Amsterdam, Schweizerbart'sche Verlagsbuchhandlung, vol. 57, no. 47, pp. 209-229, pp. L07302, (ISSN 0016-8548, ISBN 3-510-50045-8)
    Publication Date: 1979
    Keywords: Seismicity ; Tectonics ; Aftershocks ; Location ; GJRaS
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  • 6
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    In:  J. Geophys. Res., San Francisco, Schweizerbart'sche Verlagsbuchhandlung, vol. 84, no. 6, pp. 3596-3608, pp. TC1011, (ISSN 0016-8548, ISBN 3-510-50045-8)
    Publication Date: 1979
    Keywords: Seismicity ; Earthquake precursor: prediction research ; Earthquake precursor: deformation or strain ; Earthquake precursor: creep measurements ; Fore-shocks ; JGR ; FROTH ; (abstract)
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  • 7
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    In:  Tectonophys., Amsterdam, Elsevier Scientific Publishing Company, vol. 25, no. 53, pp. 159-169, pp. 1012, (ISSN: 1340-4202)
    Publication Date: 1979
    Keywords: Seismicity ; Earthquake catalog ; Karnik
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  • 8
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    In:  Bull. Seism. Soc. Am., Kunming, China, 4, vol. 69, no. 4, pp. 1209-1214, pp. L13613, (ISSN: 1340-4202)
    Publication Date: 1979
    Keywords: Magnitude ; Seismology ; Seismicity ; BSSA
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  • 9
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    In:  Tectonophys., Zagreb, Univ. Tokyo, vol. 53, no. 3, pp. 217-222, pp. B06305, (ISSN: 1340-4202)
    Publication Date: 1979
    Keywords: Earthquake ; Seismicity ; Pattern recognition ; Earthquake precursor: prediction research ; Earthquake precursor: statistical anal. of seismicity
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  • 10
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    In:  Pageoph, Tokyo, Conseil de l'Europe, vol. 117, no. 1, pp. 1172-1186, pp. L01306, (ISSN: 1340-4202)
    Publication Date: 1979
    Keywords: Earthquake precursor: prediction research ; Earthquake precursor: statistical anal. of seismicity ; Seismicity
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  • 11
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    In:  Geology, Tokyo, Conseil de l'Europe, vol. 7, no. 12, pp. 58-62, pp. L01306, (ISSN: 1340-4202)
    Publication Date: 1979
    Keywords: Subduction zone ; Plate tectonics ; ConvolutionE ; Physical properties of rocks ; Seismicity ; Crustal deformation (cf. Earthquake precursor: deformation or strain)
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  • 12
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    In:  Schweiz. mineral. petrogr. Mitt., Bonn, 3-4, vol. 59, no. 10, pp. 127-132, pp. L10306, (ISSN: 1340-4202)
    Publication Date: 1979
    Keywords: Seismicity ; Seismology ; Fault plane solution, focal mechanism ; Muller
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  • 13
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    In:  Pageoph, New York, 1-2, vol. 117, no. 1-2, pp. 1082-1147, pp. 2554, (ISSN: 1340-4202)
    Publication Date: 1979
    Keywords: Earthquake precursor: prediction research ; Earthquake precursor: statistical anal. of seismicity ; Seismicity ; FROTH ; (abstract)
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  • 14
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    In:  Geophys. J. R. astr. Soc., Tokyo, Conseil de l'Europe, vol. 56, no. 12, pp. 41-54, pp. L01306, (ISSN: 1340-4202)
    Publication Date: 1979
    Keywords: Subduction zone ; Seismicity ; Geothermics ; GJRaS
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  • 15
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    In:  J. Geophys. Res., London, Army Corps of Engineers, Woodward-Clyde Consultants, vol. 84, no. 5, pp. 4583-4591, pp. 1013, (ISBN: 0-12-018847-3)
    Publication Date: 1979
    Keywords: Subduction zone ; Seismology ; Seismicity ; Volcanology ; JGR
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  • 16
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    In:  Pageoph Special issue: Earthquake Prediction and Seismic Patterns, Reykjavík, Icelandic Meteorological Office, Ministry for the Environment, University of Iceland, vol. 117, no. 11, pp. 1195-1211, pp. L05306, (ISSN: 1340-4202)
    Publication Date: 1979
    Keywords: Earthquake precursor: prediction research ; Earthquake precursor: statistical anal. of seismicity ; Seismicity
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  • 17
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    U.S. Army Engineer Waterway Experimentation Station, Miscellaneous Paper S-73-1
    In:  Tulsa, Okl., U.S. Army Engineer Waterway Experimentation Station, Miscellaneous Paper S-73-1, vol. IUGG Volume 18, no. 85, pp. 175, (3-7723-6434-9)
    Publication Date: 1979
    Keywords: Earthquake hazard ; Statistical investigations ; Seismicity ; AL-TARAZI
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  • 18
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    In:  Pageoph, London, Geological Society, vol. 117, no. 3, pp. 1148-1171, pp. L24307, (ISBN 1-86239-117-3)
    Publication Date: 1979
    Keywords: Earthquake precursor: prediction research ; Earthquake precursor: statistical anal. of seismicity ; Fault zone ; Seismicity
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  • 19
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    In:  Pageoph Special issue: Earthquake Prediction and Seismic Patterns, Berlin, Inst. Electrical & Electronics Engineers, vol. 117, no. 6, pp. 1187-1194, pp. B04307, (ISBN: 0534351875, 2nd edition)
    Publication Date: 1979
    Keywords: Earthquake precursor: prediction research ; Earthquake precursor: statistical anal. of seismicity ; Seismicity ; FROTH ; (abstract)
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  • 20
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    In:  Geophys. Res. Lett., vol. 6, no. 9, pp. 681-684
    Publication Date: 1979
    Keywords: Earthquake precursor: prediction research ; Earthquake precursor: statistical anal. of seismicity ; Seismicity ; Statistical investigations ; Recurrence of earthquakes ; GRL
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  • 21
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    In:  Boll. Geof. Teor. Appl., Beijing, Pergamon, vol. 21, no. 17, pp. 245-310, pp. 2135
    Publication Date: 1979
    Keywords: Earthquake catalog ; Statistical investigations ; Seismicity ; AL-TARAZI
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  • 22
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    In:  Tectonophys., Münster, Amer. Sc., vol. 55, no. 4, pp. 127-153, pp. 1228, (ISBN 0-471-26610-8)
    Publication Date: 1979
    Keywords: Seismicity ; Fault plane solution, focal mechanism ; Plate tectonics
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  • 23
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    In:  Phys. Earth Plan. Int., Kyoto, California Division of Mines San Francisco, vol. 18, no. B7, pp. 341-344, pp. L24604, (ISSN: 1340-4202)
    Publication Date: 1979
    Keywords: Seismicity ; Fault zone ; Earthquake precursor: deformation or strain ; JAPAN ; Conference abstr. ; PEPI
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  • 24
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    In:  Tectonophys., Tokyo, Lawrence Livermore National Laboratory, vol. 53, no. 5, pp. 155-158, pp. L18610, (ISSN: 1340-4202)
    Publication Date: 1979
    Keywords: Seismicity ; Earthquake catalog ; Earthquake hazard
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  • 25
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    In:  proc. ESA-Council of Europe Seminar on Earthquake Prediction, Strasbourg 5-7, March 1979 - ESA SP-149, München, Soc. Professional Well Log Analysts, vol. 2, paper FFF, vol. 10, no. EL-1021R, pp. 12, (ISBN 3-933346-037)
    Publication Date: 1979
    Keywords: Earthquake precursor: prediction research ; Earthquake precursor: statistical anal. of seismicity ; Seismicity ; Earthquake catalog ; FROTH ; (fragment)
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  • 26
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    Friedr. Vieweg & Sohn GmbH
    In:  Professional Paper, Open-File Rept., Terrestrial and Space Techniques in Earthquake Prediction Research, Braunschweig, Friedr. Vieweg & Sohn GmbH, vol. 4, no. 2, pp. 585-601, (ISBN 0080419208)
    Publication Date: 1979
    Keywords: Seismicity ; Earthquake precursor: models ; China
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  • 27
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    Saint Louis University
    In:  Garland, Saint Louis University, vol. 1, no. Publ. No. 12, pp. 95-104, (ISBN: 0-08-043930-6)
    Publication Date: 1979
    Keywords: Earthquake catalog ; Seismicity
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  • 28
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    Earthquake Publ. House, 102 pp.
    In:  Beijing, Earthquake Publ. House, 102 pp., vol. 15, no. 22, pp. 65-70, (ISBN 0-87590-422-X)
    Publication Date: 1979
    Keywords: Seismicity ; Statistical investigations
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  • 29
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    UNESCO Headquarters
    In:  paper presented at the International Symposium on Earthquake Prediction, 2-6 April 1979; Science-79/Conf. 801/Col. 14/III-6, Paris, UNESCO Headquarters, vol. 10, no. PL-TR-91-2231, pp. 193-197
    Publication Date: 1979
    Keywords: Seismicity ; Earthquake precursor: statistical anal. of seismicity ; China
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  • 30
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    In:  Nature, Dordrecht, American Society of Civil Engineers, vol. 262, no. 35, pp. 259-262, pp. B09301, (ISSN: 1340-4202)
    Publication Date: 1979
    Keywords: Earth rotation ; Seismicity ; Energy (of earthquakes) ; Stress drop
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  • 31
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Gamete Research 2 (1979), S. 153-162 
    ISSN: 0148-7280
    Keywords: spermatozoa ; cell surface ; epididymis ; surface labeling ; gel electrophoresis ; proteins ; membrane ; spermatozoa ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Differences in the exposure of spermatozoa surface components during epididymal passage have been examined using lactoperoxidase-catalyzed 125I-iodination or labeling with 125I-diazodiiodosulfanilic acid. Labeled surface proteins obtained from caput and cauda epididymides were solubilized in detergent, separated by sodium dodecylsulfate polyacrylamide slab gel electrophoresis, and identified by radiography. Densitometer scans of autoradiograms revealed increased amounts or exposures of surface proteins of ∼35,000, ∼39,000, ∼50,000, and ∼78,000 molecular weight on the cauda epididymal spermatozoa.
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  • 32
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Gamete Research 2 (1979), S. 177-185 
    ISSN: 0148-7280
    Keywords: multiple enzyme forms ; acid nitrophenyl phosphatase ; sea urchin ; development ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Acid nitrophenyl phosphatases from sea urchin eggs and embryos were investigated by gel filtration. Four different forms were found in Hemicentrotus pulcherrimus, and three forms in Anthocidaris crassispina and Pseudocentrotus depressus.The first and second forms (designated AcP-1 and AcP-2) had the highest activity in the range of pH 5.6-6.0. The third (designated AcP-3) had an apparent optimum pH between pH 4.3 and 4.8, and the fourth (designated AcP-4) showed the maximum activity at pH 3.0. AcP-1 was much more thermolabile than AcP-2 and AcP-3 at 56°C. NaF inhibited AcP-2, AcP-3, and AcP-4 but not AcP-1. AcP-1, AcP-2, and AcP-3 were observed in the three species, whereas AcP-4 was not detected in A. crassispina and P. depressus. AcP-1, AcP-2, and AcP-3 were separted by gel filtration.AcP-1 and AcP-2 of A. crassispina and H. pulcherrimus were studied in developing embryos. The behavior of these forms in gel filtration changed during development, from unfertilized eggs to the pluteus stage.
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  • 33
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Gamete Research 2 (1979), S. 187-192 
    ISSN: 0148-7280
    Keywords: zona isolation ; collagenase ; receptor for sperm ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Zonae pellucidae were collected from bovine ovaries by chopping, dispersing the chopped tissue with collagenase, sieving through nylon mesh screens, and pipetting. The zonae were free of corona cell processes when examined under the scanning electron microscope. Solutions of zonae obtained with collagenase exhibited the same antigenic and sperm receptor properties as those obtained without enzyme treatment.
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  • 34
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Gamete Research 2 (1979), S. 207-211 
    ISSN: 0148-7280
    Keywords: sperm ; capacitation ; acrosome ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Suspensions of nearly 100% viable golden hamster sperm were prepared by passing washed cauda epididymal sperm through a column of 0.25-0.3 mm glass beads. Incubations of these viable sperm under in vitro capacitation conditions in volumes of 0.1 or 1 ml (2-2.5 × 106/ml) resulted in 85-92% viable sperm after four hours and 45 minutes of incubation. More than 70% of these sperm were judged to have been capacitated after four hours and 45 minutes of incubation on the basis of their having undergone acrosome reactions and the presence of high numbers of sperm exhibiting the activated motility characteristic of capacitated hamster sperm.Thus, for the first time, procedures are available that will yield large numbers of viable capacitated sperm for biochemical analysis and that will also allow other studies of hamster sperm capacitation with minimum interference from molecules released from dead sperm.
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  • 35
    ISSN: 0148-7280
    Keywords: speramtozoon-copepoda (My tilicola intestinalis) ; external morphology ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The external structure of the male gamete of Mytilicola intestinalis is studied under a scanning electron microscope and compared with transmission electron micrographs of thin sections corresponding to the different parts of same. The cell in question is long and filiform, showing, along a significant part of its length, two ridges or expansions helicoidally arranged and diametrically opposed. Four different parts or segments can be identified in this spermatozoon: segment A, characterized by its screw-like aspect; segment B, the longest, provided with well-developed helicoidal expansions; segment C, showing an uneven surface and lacking expansions; and segment D, with a smooth surface and decreasing diameter. The significance of this original structure in a spermatozoon, considered immobile until now, is discussed, stating different hypotheses with regard to the possible mobility of the cell just before fertilization takes place.
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  • 36
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Gamete Research 2 (1979), S. 283-293 
    ISSN: 0148-7280
    Keywords: in vitro fertilization ; mouse ; second polar body formation ; second meiotic division ; spindle ; polarizing microscopy ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The second meiotic division and polar body formation in mouse eggs fertilized in vitro were observed by phase-contrast and polarizing microscopy, and recorded by time-lapse cinematography. Eggs were collected from oviducts of mice that had been superovulated by injections of PMS and HCG. Some eggs, inseminated with spermatozoa that had been collected from caudae epididymides of mature male mice and cultured for two to three hours before insemination, were observed continuously on a glass slide under a phase microscope. Other eggs were inseminated in Petri dishes in a 5% CO2 incubator and examined every 20 minutes for 180 minutes. Compatible results in both sets of eggs showed that formation of the second polar body began 25-40 minutes after fusion of spermatozoon with the vitellus; it was completed 40-60 minutes later; anaphase II lasted approximately five minutes before the appearance of the furrow abstricting the second polar body. It is suggested that the furrowing associated with second polar body formation is guided by the same kind of forces that divide a cell mitotically.
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  • 37
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Gamete Research 2 (1979) 
    ISSN: 0148-7280
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
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  • 38
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Gamete Research 2 (1979), S. 193-199 
    ISSN: 0148-7280
    Keywords: double spermatozoa ; human prolactin-secreting adenoma ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: In a man with a pituitary prolactin-secreting adenoma almost only double spermatozoa were produced. These cells were almost completely enveloped in a unique membrane, a common bilocular acrosome capped two paired nuclei, and all the other organelles were double. After 120 days of treatment with 2-brom-α-ergocryptine the prolactin level was corrected, and only normal, single spermatozoa were produced. The authors suggest that a high prolactin level inhibits cell division.
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  • 39
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Gamete Research 2 (1979), S. 201-206 
    ISSN: 0148-7280
    Keywords: zona pellucida ; antibody ; ovary ; calf ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Treatment of bovine ovary sections with rabbit antibovine zona serum followed by fluorescein-conjugated goat antirabbit IgG produced a specific fluorescent staining only of the zonae pellucidae. Fluorescence was greater near the inner and outer surface of the zona, suggesting that either the same antigen occurs in higher concentration in these regions or that there is more than one antigen, the most immunogenic being located peripherally. In some atretic follicles fluorescent material appeared to diffuse into the degenerating oocyte and into the intercellular spaces of the cumulus oophorus.
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  • 40
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Gamete Research 2 (1979), S. 213-222 
    ISSN: 0148-7280
    Keywords: urethan effect ; cleavage induction ; parthenogenesis ; sea urchin ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The effect of urethan on artificial induction of cleavage in eggs of the sea urchin, Hemicentrotus pulcherrimus, was studied. When the eggs were exposed for 20 minutes to seawater containing urethan (final concentration, 0.08 M) after butyric acid-activation and then treated with hypertonic seawater, the cleavage rate was enchanced by about 1.5 times as compared with the nontreated eggs. In the eggs exposed to urethan-seawater for over 70 minutes many clear spots appeared throughout the cytoplasm. Simultaneously, the pigment granules, which had been embedded within the cortex, migrated to the inner cytoplasm and encircled a monastral centrosphere and clear spots. The clear spots were composed of microtubules much like cytasters, and in the central region of them centrioles were not yet found. The eggs in which the pigment granules disappeared from the cortex may be more susceptible to cleavage induction by succeeding hypertonic treatment.
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  • 41
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Gamete Research 2 (1979) 
    ISSN: 0148-7280
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
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  • 42
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Gamete Research 2 (1979), S. 35-42 
    ISSN: 0148-7280
    Keywords: activated motility ; temperature dependence of motility ; sperm transport ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The motility of rabbit spermatozoa recovered from the vagina, endocervix, uterus, and four regions of the oviduct was assessed visually by phase-contrast microscopy at intervals from one minute to 16 hours after a single mating. The percentage of motile cells in each sample was dependent on the temperature of recovery, ie, 23° vs 37°C, but was not influenced by the temperature of observation. Spermatozoa in the lower isthmus of the oviduct were the most temperature sensitive population to recovery at 23°C. When all manipulations and observations were performed at 37°C, the percentage of spermatozoa with progressive motility varied according to the region sampled and interval after mating. Populations from the vagina, uterus and upper regions of the oviduct usually had a high proportion of progressively motile cells with vigorous flagellar activity. Fewer spermatozoa showed progressive movement on recovery from the endocervix and lower 2 cm of the tubal isthmus and their flagellar activity was generally depressed. The decrease in flagellar beat frequency noted in the latter regions may be a major factor limiting sperm ascent in the female tract. A unique pattern of “activated” motility was seen exclusively in populations taken from the oviducts at 6 to 16 hours after mating. This motility pattern, consisting of alternating episodes of linear progressive and vigorous nonprogressive movement, may be analogous to the activated motility described for capacitated rodent spermatozoa.
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  • 43
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Gamete Research 2 (1979), S. 75-87 
    ISSN: 0148-7280
    Keywords: acrosin ; activation ; inhibitor ; proacrosin ; spermatozoa ; zymogen ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The sperm-specific proteinase acrosin (EC 3.4.21.10) is found in spermatozoa as a zymogen. We have looked for different forms of this zymogen in testicular, epididymal, and ejaculated spermatozoa from ram and have compared total sperm extracts made immediately after cell disruption with extracts made later from isolated sperm heads. We have concluded that the autoactivatable zymogen form, known generally as proacrosin, is the only form of acrosin within intact mature ram spermatozoa; no other zymogen form was detected, although lower levels of proacrosin were found in some samples of testicular spermatozoa. From studies of the activation process, it appears that ram proacrosin is truly autoactivatable; no evidence could be found for the involvement of any auxiliary enzyme. Estimations of the molecular weight of proacrosin using gel chromatography (60,000) and SDS-polyacrylamide gel electrophoresis (51,300) indicated that the zymogen is monomeric. Comparison with the molecular weight of ram acrosin (44,000 or 40,000, using the two respective methods) indicated that a single acrosin molecule is derived from each zymogen molecule. The sperm acrosin inhibitor (molecular weight 11,000 or 8,000) was present in testicular spermatozoa as well as in ejaculated spermatozoa; there was no evidence that it was produced as a result of zymogen activation.
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  • 44
    ISSN: 0148-7280
    Keywords: spermatozoon-ostracoda (Heterocypris incongruens) ; external morphology ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: In various papers on the original spermatozoon of the Ostracoda, its helicoidal disposition has been indicated as the principle characteristic of this gamete, at cell structure level as well as in its external morphology. Through a combined study with scanning electron microscope (SEM) and transmission electron microscope (TEM), we have been able to establish the corresponding relationship between the cell architecture and the spermatozoon's external morphology. In the case of Heterocypris incongruens, the helicoidal relief of the gamete's external surface along the greatest part of its length, is the result of the twisting and undulating of a structure derived from the nucleus' external membrane, endoplasmic reticulum, and Golgi apparatus, called “feather-like organelle.” In keeping with the shape of this surface relief, the spermatozoon can be divided into three regions: An anterior one with a corkscrew form, a middle one showing a relief in the form of a screw with four threads, and a posterior or tail one without helicoidal relief. Finally, we discuss the different criteria existing on the possible orientation of this spermatozoon when it moves, as well as the functional advantages that the possession of a filiform, helicoidal, and mobile gamete represents.
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  • 45
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    Gamete Research 2 (1979), S. 121-124 
    ISSN: 0148-7280
    Keywords: oocyte maturation ; LH ; ovum culture ; germinal vesicle breakdown ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Immature rats, aged 27 days, were stimulated to develop preovulatory follicles by subcutaneous injection of 15 IU of pregnant mare serum gonadotrophin (PMSG). Two days later their oocytes were collected. They were cultured under conditions that permitted continuous observation. Times of the initial stages of maturation were carefully noted, in the absence and the presence of 10 μg/ml of bovine luteinizing hormone (LH). LH did not accelerate germinal vesicle disappearance. It was concluded that the immature PMSG-treated rat was not an appropriate model for the study of LH action; it was speculated that persistence of PMSG mimicked LH in all the oocytes from such donors.
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  • 46
    ISSN: 0148-7280
    Keywords: lysin ; protease inhibitor ; sea urchin ; vitelline coat ; fertilization ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: To search the spermatozoa of sea urchins for their lysins, the eggs were inseminated in the presence of various protease inhibitors. Among them, two chymotrypsin-specific inhibitors, chymostatin and N-tosyl-L-phenylalanyl-chloro-methane, as well as p-nitrophenyl p′-guanidinobenzoate, inhibit fertilization of the sea urchins, Hemicentrotus pulcherrimus and Strongylocentrotus intermedius.A chymotrypsin-like protease is presumed to be a lysin of the sea urchins, since the inhibition of fertilization by chymostatin is remarkably diminished if the eggs are pretreated with trypsin or chymotrypsin to break the vitelline coat before insemination, and since N-tosyl-L-phenylalanyl-chloromethane, and p-nitrophenyl p′-guanidinobenzoate, as well as chymostatin, inhibit the fertilization.In all the sea urchins so far studied, elevation of fertilization envelopes is inhibited by leupeptin, antipain, soybean trypsin inhibitor, and p-nitrophenyl p′-guanidinobenzoate, all of which are potent trypsin inhibitors.Synthetic inhibitors have cytotoxic side effects on the eggs, but the microbial and plant inhibitors have no such effects.
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  • 47
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    Gamete Research 2 (1979), S. 223-233 
    ISSN: 0148-7280
    Keywords: seminal plasma DNase ; nicked sperm DNA ; sperm decondensation ; DNA template ; DNA phosphorylation ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Ejaculated rabbit spermatozoa washed with buffer prior to decondensation by Triton X-100 and dithiothreitol were good templates for DNA synthesis by Escherichia coli DNA polymerase. This result agrees with the observations of Zirkin and Chang [1977], and implies that the sperm DNA is nicked. Template activity, however, was reduced if spermatozoa were extensively washed before decondensation, and if DNase inhibitors EDTA or Na2SO4 were present during decondensation. Template activity was also low if decondensation was induced with DNase inhibitors thioglycollic acid, Na2SO3 or sodium dodecylsulphate and dithiothreitol instead of with Triton X-100 and dithiothreitol. Calf thymus DNA was completely degraded when incubated with rabbit seminal plasma or buffer-washed spermatozoa, but much less degradation was observed if EDTA, Na2SO4, thioglycollic acid, Na2SO3 or sodium dodecylsulphate were also present, or if spermatozoa were extensively washed with buffer. Centrifugation of spermatozoa through 2.05 M sucrose completely removed contaminating DNase, and such spermatozoa were inactive as DNA templates after decondensation. The DNA template activity of swollen rabbit sperm nuclei thus parallels the activity of a contaminating seminal plasma DNase. This suggest that the nicks in sperm DNA enabling it to act as a template for DNA synthesis were generated by the DNase during decondensation and thus are not a natural structural feature of the DNA. The presence of breaks in the DNA of decondensed buffer-washed spermatozoa (DNase contaminated) was confirmed by their incorporation of phosphate from [γ-32 P] ATP in the presence of the enzyme polynucleotide kinase. These spermatozoa were found to contain as few as two breaks/mole of DNA, but sucrose-washed spermatozoa (DNase free) were free of breaks. The possible use of this enzymic procedure for the assessment of sperm genome damage and the evaluation of the quality of a sperm population are discussed.
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  • 48
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    Gamete Research 2 (1979) 
    ISSN: 0148-7280
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
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  • 49
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    Gamete Research 2 (1979), S. 265-282 
    ISSN: 0148-7280
    Keywords: sperm chromatin ; nuclease digestion ; sperm decondensation ; chromatin structure ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The structure of rabbit, fowl, and Xenopus laevis sperm chromatin was explored by study of the reaction of their decondensed nuclei with DNase 1 and micrococcal nuclease. Those of rabbit and fowl were readily digested by DNase 1, and the polyacrylamide gel electrophoresis profiles of DNAs extracted from the digests were similar, each being polydisperse with a single discrete band of DNA smaller than 72 base pairs. There were differences, however, between the sperm chromatins in the course of their digestion by micrococcal nuclease. A limit digest at about 45% acid solubility was obtained with Xenopus sperm chromatin, while 90% of fowl sperm DNA was rendered acidsoluble by the enzyme. The gel profiles of the limit digests were polydisperse, but only those of rabbit and fowl sperm chromatins possessed a discrete band of DNA smaller than 72 base pairs. Bleomycin did not react with DNA of rabbit, fowl, or Xenopus spermatozoa. Since bleomycin reacts with somatic cell chromatin, and the course of DNase 1 or micrococcal nuclease digestion of sperm chromatin was different from that found for somatic cell chromatin, it would appear that sperm chromatin does not have the repeating nucleosometype structure of somatic cell chromatin. The nuclease digestion studies further suggest that the organization of rabbit and fowl sperm chromatins is similar, and is different from that of Xenopus sperm chromatin. The dependence of the structure of sperm chromatin on the composition of its basic proteins, and a possible structure for a protamine-type sperm chromatin, are discussed.
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  • 50
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    Gamete Research 2 (1979), S. 295-304 
    ISSN: 0148-7280
    Keywords: in vitro fertilization ; mouse ; sperm penetration ; zona pellucida ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Sperm penetration through the zona pellucida and fusion of the sperm head with the vitellus were observed continuously and filmed under phase optics in cumulus-free living mouse eggs inseminated in vitro with capacitated epididymal sperm. Most spermatozoa penetrated the zona pellucida, traversed the perivitelline space, and fused with the vitellus at an angle nearly perpendicular to the surface. The mean duration required for sperm to penetrate the zona pellucida was 20 minutes with a range of 15-26 minutes. Sperm traversed the perivitelline space in less than one second. The initial contact of sperm with the vitellus generally took place at the tip of the sperm head. When the tip of the sperm head contacted the vitellus there was an immediate reduction in the rate of flagellation, followed by the gradual sinking of the sperm head into the vitellus.
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  • 51
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    Gamete Research 2 (1979), S. 357-366 
    ISSN: 0148-7280
    Keywords: ova ; spermatozoa ; cryopreservation ; fertilization ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Mature unfertilized ova from superovulated hamsters were freed from all investments and frozen at -50°C. They were cooled at about 1°C/min to 0°C then at 0.8° to 0.6°C/min to -50°C. At 0°C, dimethyl sulfoxide was added to a final concentration of 1.25 M. The ova were stored at -50°C for up to four months. Thawing was performed at 2-4°C/min and followed by several washes with insemination medium. Approximately 90% of the ova were normal in appearance after thawing. The frozen and thawed ova with normal appearance could be penetrated by hamster or human spermatozoa at a rate comparable to unfrozen controls. The ability of hamster ova to tolerate storage at a relatively convenient temperature (-50°C) for long periods (tested for up to four months) makes possible their shipment at low cost to institutions lacking this resource. There they can be used for basic biological studies of sperm-egg interaction or in the clinical assessment of human sperm quality.
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  • 52
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    Gamete Research 2 (1979), S. 1-13 
    ISSN: 0148-7280
    Keywords: capacitation ; acrosomal enzymes ; rabbit sperm ; acrosomal membranes ; fertilization ; lysosomal enzymes ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Significant release of the acrosomal enzymes arylsulfatase, β-N-acetylhexosaminidase and hyaluronidase was observed following the treatment of ejaculated rabbit spermatozoa for 12 hours in 20% rabbit serum for inducing in vitro capacitation, and these sperm were capable of in vivo fertilization; however, the treatment of sperm for 15 minutes in high ionic strength (380 mOsm/kg) or low ionic strength medium (305 mOsm/kg) for in vitro capacitation did not result in any significant release of the above enzymes nor were the sperm capable of in vivo fertilization. Serum-treated spermatozoa remained significantly motile following the 12 hour treatment, 51% underwent the acrosome reaction and were capable of fertilizing 66% of the ova in vivo. Identical serum treatment of lysosomes from rabbit liver resulted in a comparable release of the lysosomal enzymes. Serum treatment for in vitro capacitation resulted in vesiculation of the anterior margin of half the spermatozoa, but left their inner acrosomal membranes and equatorial segments intact. A biochemical relationship between the release of acrosomal enzymes and capacitation is suggested.
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  • 53
    ISSN: 0148-7280
    Keywords: fertilization ; acrosome reaction ; sea urchins ; cross-fertilization ; species specificity ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Sperm of Hemicentrotus pulcherrimus undergo the acrosome reaction in the jelly coat or on the surface of the vitelline layer of Pseudocentrotus depressus eggs and can fertilize the latter, whereas those of P depressus do not undergo the acrosome reaction even after they strike the vitelline layer of H pulcherrimus eggs and cannot cross-fertilize.In the latter combination, however, if cross-insemination is performed in the presence of homologous egg water, cross-fertilization becomes less difficult than in normal seawater, and percentage cross-fertilization rises as does percentage acrosome reaction. It is suggested that the cross-fertilizability of this combination depends highly on the inductivity of the acrosome reaction. The reason why such a causal relation is observed is discussed.
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  • 54
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    Gamete Research 2 (1979), S. 25-34 
    ISSN: 0148-7280
    Keywords: spermatozoa ; spermiogenesis ; male germ cells ; centriole ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: In the course of the reorganization and degeneration of the proximal centriole in the mature acentriolate spermatozoon of the Mongolian gerbil, both the proximal and distal centrioles appear in the early cap phase of spermatid development. During the acrosome phase, both distal and proximal centrioles become highly active in the formation of a segmented column. The proximal centriole becomes actively involved in the formation of the capitulum, while the distal centriole forms the axonemal complex and dense fibers. During the maturation phase of spermatid development, the “pinwheel” arrangement of the proximal centriole becomes an “S”-shaped structure, turned 90° on its vertical axis. The few “doublet” microtubules that can be detected later in that stage completely disappear during spermiation. The distal centriolar area develops a single central pair of microtubules and membranous elements. Another prominent feature in the neck region of the gerbil spermatozoa is the presence of two dense rudimentary columns in association with the mitochondria. Although their density is similar to that of the other columns, these two columns have no connection with the dense fibers; in fact, they are closely associated with the mitochondria.
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  • 55
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    Gamete Research 2 (1979), S. 53-64 
    ISSN: 0148-7280
    Keywords: spermatozoa ; plasma membrane ; glycoproteins ; free acidic groups ; farm mammals ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Ejaculated spermatozoa of boars, bulls, rabbits, and rams were embedded in glycolmethacrylate and thin sections stained with phosphotungstic acid at low pH in order to observe the distribution of glycoproteins of the plasma membrane. Colloidal iron hydroxide was also used to detect the free acidic groups present on the sperm surface. Species-specific patterns of localizations of glycoproteins and linked negative charges were observed. The distribution was sometimes homogeneous as in bull, but generally heterogeneous in the other species. The significance of the results on sperm surface components and the practical interest to know their normal distribution are discussed.
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  • 56
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    Gamete Research 2 (1979), S. 43-51 
    ISSN: 0148-7280
    Keywords: spermatozoa ; acrosome ; glycoproteins ; farm mammals ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Ejaculated spermatozoa of boars, bulls, rabbits, and rams were fixed with glutaraldehyde and embedded in glycolmethacrylate. Thin sections were treated with phosphotungstic acid at low pH in order to localize cellular glycoproteins stained by the PAS technique at the light microscope level. At the ultrastructural level the glycoproteins were segregated in the anterior segment of mature spermatozoa. The distribution of these glycoproteins in the anterior segment was not homogeneous; it appeared species-specific in detail, but as a rule, the maximum concentration was observed in a superficial layer, especially in the marginal thickening. The localization of other acrosomal components (eg, crystalline and basic proteins) is also reviewed. The origin and significance of the segregation of proteins and glycoproteins in the acrosome are discussed in relation to the fact that the acrosomal enzymes analyzed so far are glycoproteins.
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  • 57
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    Gamete Research 2 (1979), S. 65-73 
    ISSN: 0148-7280
    Keywords: embryo transfer ; embryo culture ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Embryo transfer experiments were carried out to study the developmental capacity of cultured rabbit embryos when transferred to recipients of variable postovulatory maturity. Rabbit embryos were flushed from the oviduct at 26 hours postcoitum (pc) and cultured in a modified Ham's F-10 medium supplemented with bovine serum albumin (BSA) for a period of 70 hours. At 96 hours pc the cultured embryos, which ranged from the early morula to the expanding blastocyst stage, were transferred to pseudopregnant recipients mated to vasectomized males 36 to 96 hours prior to the transfer procedure. Greatest embryo survival occurred when transfers were made to either the oviducts or uterine horns of recipients at 48 hours pc. Intermediate results for both implantation rates and number of young born were obtained with recipients at 36, 60, 72, and 84 hours pc. Transferred embryos consistently failed to survive the uterine environment of recipients 96 hours pc at transfer although this group was synchronous with embryonic chronological age. Oviductal transfers were generally more successful than uterine transfers. Markedly higher rates of embryo survival resulted from embryos that were collected 60 and 72 hours pc and transferred directly to synchronous recipients without an interim period of culture. Dissimilarity of development for in vivo grown rabbit embryos and those cultured in synthetic medium is demonstrated.
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  • 58
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    Gamete Research 2 (1979), S. 99-104 
    ISSN: 0148-7280
    Keywords: sperm penetration ; premature cortical reaction ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The method of in vitro fertilization was applied to test a previous suggestion that the lowered fertilizability of the tubal oocytes of female KE strain mice and the high resistance of their zona pellucida to proteolytic enzymes, are due to the premature cortical reaction taking place near the time of ovulation. Therefore higher fertilizability of ovarian oocytes is expected.The effectiveness of F1 hybrid sperm penetration into ovarian and tubal KE oocytes confirmed these assumptions. The ovarian KE oocytes recovered 9-10 hours after administration of human chorionic gonadotropin (HCG) showed significantly higher penetrability (70-83%) than did the tubal oocytes recovered 12 hours after HCG (about 50%) and 14-16 hours after HCG (20%).Similar results were obtained with C57 oocytes. Sperm penetration into ovarian oocytes (10 hours after HCG) was much more effective (67%) than into tubal oocytes (18%); this finding correlated with more rapid zona dissolution by chymotrypsin. On the basis of these results one might speculate that premature cortical reaction takes place also in the C57 strain.
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  • 59
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    Gamete Research 2 (1979), S. 105-105 
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
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  • 60
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    Gamete Research 2 (1979) 
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
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  • 61
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    Gamete Research 2 (1979), S. 137-145 
    ISSN: 0148-7280
    Keywords: progesterone-induced maturation ; methylxanthines ; chloera toxin ; phosphorylation ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: During the course of maturation of Xenopus laevis oocyte a burst of phosphorylation occurs around germinal vesicle breakdown. At the same time a relative drop in a unique phosphoprotein (protein I; mot wt ∼40,000) is observed. Enucleation of [32P] labeled oocytes has shown the cytoplasmic localization of protein I. Methylxanthines and cholera toxin, which inhibit progesterone-induced maturation, block the burst of phosphorylation and do not change the amount or the distribution of [32P] phosphoproteins.
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  • 62
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    Gamete Research 2 (1979), S. 125-135 
    ISSN: 0148-7280
    Keywords: oogenesis ; oocyte growth ; Xenopus laevis ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: When female Xenopus laevis are injected with [3H]-vitellogenin or [14C] N-acetyl glucosamine, most of the labeled material becomes associated three days later with oocytes having a diameter of 0.9-1.1 mm; smaller and larger oocytes are less labeled. With time, the pattern of labeling shifts to larger oocytes, indicating that those oocytes initially labeled continue to grow. We have measured such shifts as a function of time to provide estimates for oocyte growth rates from the end of stage III (diameter = 0.6 mm) to stage VI (diameter = 1.2 mm). The total time required for oocytes to progress through this size increase is 16-24 weeks in unstimulated females and 9-12 weeks in human chorionic gonadotropin (hCG)-stimulated females. The fastest rate of growth occurs from mid-stage IV (approximately 0.8 mm diameter) until midstage V (1.2 mm diameter), which corresponds to the period of most pronounced vitellogenin uptake. The relative proportion of oocytes within this size range is also reduced, as predicted under steady-stage conditions. Evidence is also presented which indicates that the steady-state level of full-grown oocytes is maintained by a combination of replenishment and atresia. These results provide the first description of the kinetics of oocyte growth in X laevis females maintained under normal laboratory conditions and should be useful for any considerations of macromolecular events occurring during oogenesis.
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    Zeitschrift für die chemische Industrie 91 (1979), S. 447-448 
    ISSN: 0044-8249
    Keywords: Chemistry ; General Chemistry
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    Topics: Chemistry and Pharmacology
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    Zeitschrift für die chemische Industrie 91 (1979), S. 450-450 
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    Keywords: Chemistry ; General Chemistry
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    Zeitschrift für die chemische Industrie 91 (1979), S. 550-560 
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    Topics: Chemistry and Pharmacology
    Notes: Wie die Anwendung chromatographischer Techniken ergab, sind Lipide mit langkettigen Alkyl- oder 1-Alkenylketten - Alkoxylipide oder Etherlipide genannt - in menschlichem und tierischem Gewebe weit verbreitet. Man unterscheidet neutrale Alkoxylipide, d. h. 1-O-Alkyl- oder 1-O-(1-Alkenyl)-2, 3-di-O-acylglycerole, und ionische Alkoxylipide, die an C-3 über einen Phosphat-Rest mit Aminoethanol, Cholin oder Serin verknüpft sind. 1-O-Alkylglycerole, 1-O-(1-Alkenyl)glycerole und andere natürlich vorkommende Alkoxylipide können mit hohen Ausbeuten synthetisiert werden. Auch 2-Alkyl-, 1, 3-Dialkyl- und Trialkylglycerole, die in der Natur nicht vorkommen, sind synthetisch zugänglich. Die neutralen Alkoxylipide werden für bio-medizinische Untersuchungen verwendet, z. B. als Substrate in Systemen mit Acyl-Hydrolasen oder bei Untersuchungen der Fettresorption. Die Biosynthese der Alkoxylipide ist in großen Zügen aufgeklärt. Der Alkyl-Rest stammt aus einer gesättigten oder einfach-ungesättigten Fettsäure. 1-O-(1-Alkenyl)-2-O-acylglycerophosphorylaminoethanole („Plasmalogene“) werden offenbar aus den entsprechenden 1-Alkylverbindungen gebildet; in der Cholin-Reihe ist das nicht möglich. Trotzdem kommen „Aminoethanol-“ und „Cholin-Plasmalogene“ in den meisten Geweben gemeinsam vor.
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  • 77
    ISSN: 0044-8249
    Keywords: Chemistry ; General Chemistry
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    Topics: Chemistry and Pharmacology
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  • 78
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    Zeitschrift für die chemische Industrie 91 (1979), S. 1024-1025 
    ISSN: 0044-8249
    Keywords: Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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  • 79
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    Zeitschrift für die chemische Industrie 91 (1979), S. 1025-1026 
    ISSN: 0044-8249
    Keywords: Chemistry ; General Chemistry
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    Topics: Chemistry and Pharmacology
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  • 80
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    Zeitschrift für die chemische Industrie 91 (1979), S. 1026-1028 
    ISSN: 0044-8249
    Keywords: Chemistry ; General Chemistry
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    Topics: Chemistry and Pharmacology
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  • 81
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    Zeitschrift für die chemische Industrie 91 (1979), S. 1028-1030 
    ISSN: 0044-8249
    Keywords: Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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  • 82
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    Zeitschrift für die chemische Industrie 91 (1979), S. 1032-1032 
    ISSN: 0044-8249
    Keywords: Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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  • 83
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    Journal of Morphology 159 (1979), S. 151-183 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The unusual lymphogranulopoietic bone marrow of the large lungless salamander Plethodon glutinosus was examined by light and electron microscopy. Developing neutrophils, eosinophils, and fat cells were found in large numbers, while lymphocytes of various sizes, plasma cells, plasmablasts, macrophages, pigment cells, and fibroblasts were present in more moderate numbers. Basophils were observed only rarely. Macrophages were found in extravascular locations and did not appear to be associated directly with the walls of the blood vessels supplying the marrow. Both neutrophils and eosinophils seemed to arise from small precursor cells whose ultrastructural features bore a resemblance in some ways to those of mammalian myeloblasts described by Bainton and Farquhar ('66). Developing neutrophils and eosinophils seemed to produce only single populations of specific cytoplasmic granules, rather than both primary (azurophilic) and secondary (specific) inclusions, as are produced typically by mammalian granulocytes. Both eosinophilic and neutrophilic granules were formed in association with Golgi complexes; and eosinophilic granules were much larger, more densely stained, and more regularly rounded in shape than the inclusions of developing neutrophils. Peroxidase activity was associated with the specific granules of neutrophils but seemed to be lacking in the granules of eosinophils. The specific granules of eosinophils were especially unusual because they contained irregularly shaped, lightly stained cores which occasionally displayed a distinctly crystalline substructural organization. The specific granules of basophils also possessed a prominent crystalline organization. The overall appearance of the marrow of Plethodon suggests that it functions not only as a valuable source of neutrophils, eosinophils, and cells of the lymphoid series, but also as a part of the phagocytic system of the animals and as an important repository for fat.
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  • 84
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: When Aedes aegypti females first emerge as adults, their oocytes possess no yolk. The abdominal fat body cells contain large quantities of lipid, protein, and glycogen, and possess many free ribosomes, but have very little rough endoplasmic reticulum (RER). When the females are starved for four days, their oocytes form fine lipid and protein yolk endogenously, the latter being located mainly around the nucleus. The adipocytes in these fasted mosquitoes have greatly reduced amounts of lipid, protein and glycogen and contain many cytolysosomes. Seven hours after 4-day-starved females had fed on blood, their oocytes begin filling with exogenous protein yolk at the oolemma, and lipid arises endogenously throughout the ooplasm. At this hour, the fat cells have synthesized more RER than is seen in unfed controls. Twenty-four hours post blood meal, the follicle cells have secreted discrete endochorionic plaques onto the oolemma. At this period, the adipocytes are densely filled with RER, and show for the first time many Golgi bodies and protein inclusions. They have noticeably less glycogen than at seven hours. Within 48 hours after mosquitoes have fed on blood, the endochorion forms a continuous layer around the steadily enlarging egg which is synthesizing additional protein and lipid yolk. Concurrently, the adipocytes show a greatly increased amount of glycogen and a significant reduction of RER. By the sixtieth hour after the blood meal, the follicle cells are attenuated, and the fat cells have less RER and more glycogen than at 48 hours. The nurse cells steadily decrease in size during vitellogenesis and release material onto the micropyle.
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  • 85
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    Journal of Morphology 159 (1979), S. 221-232 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The electron microscopical structure of the type “B” cells in the rectal pad epithelium of Locusta is described. The type “B” cells occur singly in the distal region of the rectal pad epithelium. They are characteristically goblet shaped and join with contiguous type “A” or rectal pad cells, near the apical surface by means of a restricted region of septate desmosomes. Type “B” cells possess a microvillate apical membrane, with the villi arranged as a rosette overlying the apical inaginations of adjacent type “A” cells.Large numbers of microtubules and vacuoles of various sizes containing an assortment of inclusions are present in the apical region of the type “B” cells. Many of the microtubules insert distally on hemidesmosomes located in the apical plasma membrane. Rough endoplasmic reticulum and mitochondria are also present but neither are abundant. The possible significance of these findings is discussed.
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  • 86
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The central nervous system of the sessile barnacle, Semibalanus cariosus (Pallas), has been studied with the particular aim of determining the locations of neuron somata in relation to peripheral nerves. This was accomplished by tracing peripheral nerves using dissection and methylene blue staining techniques, histological methods, and by permitting cobaltous chloride to diffuse via axons into ganglia (“backfilling”).The neuron maps resulting from the study reveal some well-defined sub-systems, a considerable degree of functional clumping of neuron somata, and some unexpected projections of neurons in the CNS. Neurophysiological studies based on these findings are in progress.
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  • 87
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    Journal of Morphology 159 (1979), S. 311-329 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Normal development of the urostyle is described during late stages of metamorphosis in five species of anurans: Xenopus laevis (Daudin), Bufo americanus Holbrook, Pseudacris triseriata (Wied), Hyla chrysoscelis Cope, and Rana pipiens Schreber. The developing urostyle of all five species is composed of essentially the same cartilaginous elements: one pair of basidorsals above the notochord and the subtended hypochord. Among the five species there is variation in such details as the number of spinal nerve foramina and the degree of fusion of the basidorsals; however, both the hypochord and basidorsals are very similar in all five genera examined. Consideration of the literature suggests that contradictory descriptions of the developing urostyle result from (1) varied methods of study (alizarin-staining of whole specimens or serial cross-sections), (2) the variety of species examined, and (3) the particular stage of development of the tadpole described by an investigator.
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  • 88
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    Journal of Morphology 159 (1979) 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
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  • 89
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Fine structure of the scales of Fundulus heteroclitus was examined by scanning and transmission electron microscopy. The concentric ridges of the scale surface were characterized by the presence of minute, highly calcified, denticles or tooth-like processes. Needle-shaped crystals of hydrox-yapatite were precipitated not only in the osseous layer but in the intimate lamellae of the fibrillary plate except in portions just below the grooves. The calcification of the osseous layer was observed to proceed by filling the matrix with patches of crystals. The fibrillary plate appeared to calcify by invasion of crystals from the upper calcified zone into spaces between collagen fibers.
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  • 90
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    Journal of Morphology 159 (1979), S. 81-87 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Study of the fine structure of the macronucleus in Euplotes eurystomus, a ciliate protozoon, during various stages of the cell division cycle has yielded new information about intranuclear helices. They are frequently observed at the periphery of chromatin bodies or next to the nuclear envelope, and they appear to be a constituent of nucleoli. The fibril that forms a helix is about 11-15 nm thick, and torus profiles of helices cut in cross section are about 35 nm in diameter. In substructure the helix is composed of a thin strand 3-5 nm thick which is coiled to form the 11-15 nm fibril; so the helix is a super-coiled structure. The intranuclear helices are present in the macronucleus throughout the cell cycle. They do not show obvious changes of relative abundance nor changes of relative localization in the nucleus, with one exception: they were never observed in the diffuse zone of replication bands. Evidence is presented indicating that nuclear helices migrate to the cytoplasm through nuclear pores. Although the chemical composition of the Euplotes intranuclear helices is unknown, information in the literature on similar helices in Amoeba indicates that they contain RNA and not DNA. The observations on Euplotes helices are consistent with a concept of “packaged” RNA for transport to the cytoplasm.
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  • 91
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    Journal of Morphology 160 (1979), S. 299-321 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Nematode amphids are a pair of lateral cephalic sense organs, each comprising a group of sensory endings terminating in a cuticle-lined pit. In Syngamus trachea, a parasite of birds, each amphid is surrounded by two non-nervous supporting elements, a large gland cell basally and a smaller supporting cell anteriorly. The amphidial glands display high levels of secretory activity from five to six days postinfection. Secretory material is discharged through the lumen of the sense organ onto host tissue. The ultrastructure of amphids and amphidial glands has been investigated in newly moulted, immature and mature adults to trace the development of glandular activity and its effect on amphid-amphidial gland relationships. In newly moulted adults, the glands have very low levels of secretory activity and appear to act only as supporting cells to the amphids. As secretory activity increases, the gland cell membrane surrounding the sensory endings is elaborated into a reticulum which probably forms the secretory surface. In mature adults the amphid pit is swollen and filled with secretion; the sensory endings are relegated to the periphery of the lumen. It is suggested that amphidial glands develop from typical supporting cells, but acquire a new role possibly associated with parasite attachment.
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  • 92
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    Journal of Morphology 159 (1979) 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
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  • 93
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    Journal of Morphology 159 (1979), S. 131-143 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Eggs of the turtle Trionyx spiniferus are rigid, calcareous spheres averaging 2.5 cm in diameter. The eggshell is morphologically very similar to avian eggshells. The outer crystalline layer is composed of roughly columnar aggregates, or shell units, of calcium carbonate in the aragonite form. Each shell unit tapers to a somewhat conical tip at its base. Interior to the crystalline layer are two tertiary egg membranes: the outer shell membrane and the inner shell membrane. The outer shell membrane is firmly attached to the inner surface of the shell, and the two membranes are in contact except at the air cell, where the inner shell membrane separates from the outer shell membrane. Both membranes are multi-layered, with the inner shell membrane exhibiting a more fibrous structure than the outer shell membrane. Numerous pores are found in the eggshell, and these generally occur at the intersection of four or more shell units.
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  • 94
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    Journal of Morphology 161 (1979), S. 1-21 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: As a part of a continuing study of unusual molluscan tissues, the “chondroid” tissue (Hyman, '67) associated with the anterior and posterior aortae of the slug (Limax maximus) was examined by light and electron microscopy. Unlike the odontophoral tissue of this species (Curtis and Cowden, '77), the “chondroid” tissue comprising the adventitial layer of the aorta consists of large, glycogen-filled cells with characteristic arrays of pores in their plasma membranes resembling those of the “globular” cells (Rogers, '69; Fernandez, '71); “fibrocytes” (Nicaise et al., '66; Baleydier et al., '69; Nicaise, '73); “Blasenzellen” or “Leydig” cells (Wondrak, '69; Stang-Voss, '70; Buchholz et al., '71; Stang-Voss and Staubesand, '71; Wolburg-Buchholz, '72); or “pore” cells (Sminia, '72; Beltz, '77) of other mollusks. The anterior and posterior aortae are very similar in organization, except that the anterior aorta is larger in diameter; its wall is thinner; and it lacks calcification. Both the anterior and posterior aortae possess a loosely organized (incomplete) endothelial layer surrounded by two layers of innervated smooth muscle. The smooth muscle cells possess fibrous surface specializations resembling hemidesmosomes as well as large numbers of tubular or rounded vesicles in association with their plasma membranes. Blood cells (amoebocytes) containing large glycogen deposits and distinctive membrane-enclosed cytoplasmic inclusions can be found occasionally in the walls of the vessels.
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  • 95
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    Journal of Morphology 161 (1979), S. 23-38 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Glycogen metabolism has been studied during the development of the early chick embryo, at the cytochemical and ultrastructural levels. Two waves of glycogen synthesis and breakdown have been found. In the first, free clusters of glycogen particles are synthesized at late oogenesis. These clusters are found later in invaginations of the membrane of vesicles containing a floc-cular material (FLOV). The glycogen clusters are degraded there during ovulation and the first hours in the oviduct. The second wave of glycogen synthesis begins before cleavage, reaching a maximum at mid-uterine age. This second wave occurs in another type of vesicle (GLYV), which eventually disintegrates releasing free clusters of glycogen granules. This glycogen is degraded in membranous structures containing a floccular material, as in the first wave of degradation. The degradation ends at the late uterine stages, and at the same time numerous ribosomes are formed. This period corresponds to area pellucida formation, which probably depends on the energy liberated during the second wave of glycogen degradation.
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  • 96
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: A sensory papilla is described in the eyestalk of the crayfish Astacus leptodactylus during the last embryonic stages and during larval stages by light microscopy. This region was also investigated with the scanning electron microscopy, which showed sensory hairs in the postmolt adult; they disappear during intermolt and premolt. Simultaneous cyclic changes in hair papillae are observed in the hypodermis. The possibility of a chemoreceptive function is discussed.
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  • 97
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    Journal of Morphology 161 (1979), S. 53-77 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Formation of nuclear envelopes during the last cleavage mitosis and the formation of the cell membranes during the cellularization of the blastoderm have been studied ultrastructurally in the blowfly egg. Dense bodies arising from yolk granules by budding could contain membrane material destined to be incorporated into the new membranes of the blastoderm. The presence of transitional structures indicates that these bodies can be converted into dark multivesicular bodies. Large amounts of endoplasmic reticulum are found around the mitotic nuclei. Clusters or branched chains of vesicles associated with this are interpreted as evidence for the formation of endoplasmic reticulum by the breakdown of dark multivesicular bodies. Nuclear envelopes of mitotic daughter nuclei probably originate from endoplasmic reticulum. The egg contains both intranuclear and extranuclear annulate lamellae.The main events of cytokinesis are furrow initiation and cell membrane growth during the slow first phase, but probably only cytokinetic movement during the rapid second phase. On the assumption that cell membrane growth occurs by incorporation of complete membrane pieces, the addition of coated vesicles and/or light multivesicular bodies is definitely most probable. Some intermediate profiles indicate that light and dark multivesicular bodies are related. The membrane needed for second phase cytokinesis could well be provided by the unfolding of surface microvilli and protuberances of the furrow canal.
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  • 98
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    Journal of Morphology 161 (1979) 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
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  • 99
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    Journal of Morphology 161 (1979), S. 79-109 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The hindgut of the semi-terrestrial tardigrade, Milnesium tardigradum was examined with light and electron microscopy. The hindgut consists of a cloaca and an anterior hindgut. It is delineated anteriorly by the pylorus into which four Malpighian tubules empty and posteriorly, by a broad cloacal slit. A single oviduct enters the hindgut at the junction between the cloaca and the anterior hindgut. Two pairs of muscles insert on the cloaca and anterior hindgut respectively. Electron microscopic observations demonstrate that the anterior hindgut is a specialized transporting epithelium. The luminal surface is covered by a thin layer of cuticle which penetrates into channel-like invaginations. Numerous mitochondria are concentrated apically. The basal and lateral surfaces are also folded. The cells are joined apically by deep tight junctions and a simple basal lamina lines the entire hindgut. The cloaca which receives the contents of the gut and Malpighian tubules as well as gametes of the reproductive tract is a transitional organ that exhibits several characteristics of the hypodermis and anterior hindgut. The cuticle of the cloaca changes sequentially from the complex structure of the integument to a simple layer of the anterior hindgut. The function of the hindgut is discussed with emphasis on the possible response of the anterior hindgut to a hypoosmotic habitat, evaporative water loss during the induction of anhydrobiosis and low oxygen tension.
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  • 100
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    Journal of Morphology 161 (1979), S. 111-121 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Reticulate scales develop as radial symmetrical anlagen, in contrast to scuttate scales which appear initially as “epidermal placodes.” Unlike scuttate scales whose outer and inner epidermal surfaces elaborate β-and α-type keratins, respectively, reticulate scales elaborate only one type of epidermal surface which has been reported to give an α-type, X-ray diffraction pattern. We find that, histologically and ultrastructurally, this surface differs from either epidermal surface of scuttate scales. The keratinizing cells become filled with long interweaving bundles of α-filaments which aggregate into rather homogeneous α-fibrils. Keratohyalin granules, which have been shown to be associated with other keratinizing regions in the bird, do not form during the keratinization of reticulate scale epidermis.
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