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  • Life and Medical Sciences  (35)
  • Humans
  • Lunar and Planetary Science and Exploration
  • ASTROPHYSICS
  • 1935-1939  (35)
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Years
Year
  • 11
    Electronic Resource
    Electronic Resource
    Pigmentation changes in tadpoles of Rana pipiens following centrifugation during the early gastrulaAided by a grant from the rockefeller foundation for work on cellular biology. (1938)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 63 (1938), S. 477-489 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Centrifuging the eggs of Rana pipiens in the early gastrula stage prevents the formation of the hypophysis in some of the tadpoles. The absence of the melanophorotropic hormone normally secreted by the hypophysis seems to be responsible for the contraction of the pigment cells. In addition, there are actually fewer pigment cells present in both the dermal and epidermal layers of the light tadpoles than there are in the controls. The paleness, therefore, of the tadpoles seems to be due to both a contraction of the pigment cells present and to an actual reduction in their number. The failure of the hypophysis to develop was brought about by centrifuging at an earlier stage in development of the embryo than in previous extirpation studies. The effects produced by centrifuging that are responsible for the failure of the hypophysis to develop are unknown. However, it is suggested that interference in some way with the presumptive hypophysis-forming tissue has resulted in an inactivation of its inductive potencies.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1050630304
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  • 12
    Electronic Resource
    Electronic Resource
    The effect of fat extraction on Golgi bodies of kidney cells of the frog (1936)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 59 (1936), S. 441-451 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Frog kidney, when fixed in 4 per cent formalin and subsequently treated with Kolatchev solutions, is found to contain osmiophilic bodies which not only appear identical to the Golgi substance of Kolatchev fixed controls but which also resist bleaching in hydrogen peroxide or potassium permanganate solutions. If a formalin fixed kidney is dehydrated and extracted with various fat solvents and subsequently fixed with the Kolatchev technique, Golgi bodies are usually completely removed but occasionally cells are found which contain spherical globules of osmiophilic substance scattered through the cytoplasm.Kidney tissue fixed in a mixture of 95 parts of alcohol plus 5 parts of formalin before application of the Kolatchev solutions does not contain Golgi bodies. The same results are obtained if benzene is used instead of alcohol and formalin. Striated muscle, when treated in a similar manner, contains darkly stained (Z) and (M) membranes, therefore the osmophilic substance present in muscle quite widely daerent, chemically and physically from that contained in kidney cells.It is apparently an established fact that formalin preserves phospholipids in tissues nnd this investigation has shown that Golgi bodies in kidney cells can be demonstrated following fixation in formalin. Moreover, the Golgi bodies, which are preserved by formalin, can be removed by extracting the tissue with fat solvents. This evidence, therefore, strengthens the hypothesis that true Golgi substance is phospholipid in nature.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1050590303
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  • 13
    Electronic Resource
    Electronic Resource
    The multiple chromosomes of Paratylotropidia brunneri Scudder (Orthoptera: Acrididae)Aided by grant from the rockefeller foundation for work on cellular biology. (1938)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 63 (1938), S. 289-299 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: There are 19 chromosomes in diploid cells of male Paratylotropidia brunneri; of these, four are V-shaped multiples. There are twenty chromosomes in diploid cells of females; of these, four are V-shaped multiples. If the two arms of each multiple are counted as separate chromosomes, we have the usual number of chromosomes for the Acrididae, i.e., twenty-three in male and twenty-four in female.There are nine chromosomes in the first spermatocyte divisions: seven tetrads, one octad and a decad. The latter is made up of the accessory chromosome associated with an octad.One of the V-shaped multiples in the male is limited to that sex. The homologue of one of the dyads of which it is composed is a free dyad, the homologue of the other forms a V-shaped multiple with the accessory chromosome. The V-shaped multiple limited to the male shows differential heteropycosis in the prophases of the first spermatocyte. There is evidence that its homologous parts are isolated from each other as far as crossingover is concerned.A study of the first maturation division of the heterogametic sex is essential for the identification of the sex chromosome.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1050630206
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  • 14
    Electronic Resource
    Electronic Resource
    The origin and fate of the entoderm elements in the embryogeny of porcellio laevis latr. and armadillidium nasatum B. L. (isopoda)Contribution No. 200 from the Department of Zoology, Kansas State College of Agriculture and Applied Science, Manhattan, Kansas. (1939)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 64 (1939), S. 401-429 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1050640303
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  • 15
    Electronic Resource
    Electronic Resource
    The thyroid and parathyroid glands of the Barasingha deer, with particular reference to autofluorescence, fat and pigment (1939)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 65 (1939), S. 297-321 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1050650206
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  • 16
    Electronic Resource
    Electronic Resource
    Seasonal changes in the testis of the musk turtle, Sternotherus odoratus L.Aided by a grant from the committee for research in problems of sex of the national research council, as administered by prof. emil witschi. (1938)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 63 (1938), S. 301-317 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The spermatogenetic cycle of the testis of the musk turtle is limited to the summer months of the year, and closely parallels that of the anuran Amphibia. Spermatozoa are present in the testis from September to May, and breeding may occur in either fall or spring. A pronounced increase in the size of the epididymis and a corresponding decrease in the size of the testis occurs at the end of the cycle (September).During the months of March, April and May, all spermatozoa are eliminated from the seminal tubules, and the germinal epithelium is built up in preparation for spermatogenesis. Spermatogonial divisions occur in small numbers in May, and the division tempo increases during June. Primary spermatocytes and maturation divisions appear after the middle of June, and continue through July and August. Spermiogenesis begins in late July, is in full progress in August, and is practically completed by October. Laboratory specimens usually show an active spermatogenesis in winter, but it is not probable that a second spermatogenetic cycle occurs in specimens under normal hibernating conditions.No seasonal changes are observed in the interstitial cells of the testis, and no seasonally variable secondary sex characters are known for turtles. Special studies of the problem are being conducted.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1050630207
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  • 17
    Electronic Resource
    Electronic Resource
    The trophotaeniaeThe term trophotaeniae, ‘growth ribbons,’ was introduced by Hubbs and Turner ('37). of the goodeidae, a family of viviparous cyprinodont fishes (1937)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 61 (1937), S. 495-523 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The embryos of twenty-one species of the family Goodeidae have extensive rectal processes (trophotaeniae) which serve as absorptive organs, by means of which the embryos while they are retained in the ovarian cavity absorb substances dissolved in the ovarian fluid. Embryos of three species have not been available for study. No trophotaeniae are present in one species Ataeniobius toweri. There are three general types of trophotaeniae, rosette, sheathed and unsheathed. The structure of the trophotaeniae is sufficiently constant in each species to be used in species determination.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1050610306
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  • 18
    Electronic Resource
    Electronic Resource
    The cytology of the hypophysis cerebri of the batA thesis submitted from the Department of Zoölogy for the degree of Doctor of Philosophy at the University of Missouri. The work was supported in part by a grant from the Rockefeller Foundation administered by Prof. Mary J. Guthrie. (1936)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 60 (1936), S. 127-157 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: A cytological study of the hypophyses of more than 100 female bats, collected at fortnightly intervals from October to April, is reported. The bats were decapitated within 24 hours after collection. and then hypophyses fixed in Champy's fluid or Helly's fluid followed by staining by the acid fuchsin-thionin-aurantia method of Kull.The pars distalis, pars intermedia, and pars nervosa lie adjacent to one another in the flattened gland. In some hypophyses the lumen of the original buccal evagination persists as a narrow residual cleft which may be expanded to form ciliated vesicles.Observations on cell size. nucleoplasmie ratio, degree of chromaticity in the nucleus, staining reactions of the cytoplasm and secretory granules, and the presence of chondriosomes, secretory granules, and vesicles in the cytosome are recorded. Secretory cells and histiocytes are idintified. Sceretoty cells are found in successive stages of growth, differentiation, secretion, and degeneration. Cells which have discharged their secretion apparently do not resynthesize secretory granules. Mitosis is not observed. The available evidence suggests utilization of a large supply of embryonic cells as the source of the fully differentiated cells. The cells of the pars intermedia are interpreted as potential secretory cells which do not differentiate under the inadequate nutrient conditions of that region.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1050600107
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  • 19
    Electronic Resource
    Electronic Resource
    Cursorial adaptations in birds. Limb proportions in the skeleton of geococcyx (1938)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 63 (1938), S. 207-217 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Comparison of intramembral and trunk/limb proportions in the roadrunner (Geococcyx) and two related genera of cuckoos (Coccyzus and Crotophaga), together with a consideration of their habits of locomotion, lead to the following two generalizations: (1) The incipient cursorial leg of more primitive, arboreal birds, with the metatarsus shorter than the femur, is not an efficient mechanism for bipedal terrestrial locomotion. The direct adaptation to the cursorial habit in terrestrial birds lies in the further elongation of the whole leg, the distal segments undergoing a relatively greater elongation than the femur; the greatest degree of elongation is shown by the most distal segment. (2) When the development of terrestrial, cursorial habits in birds leads to diminished use, or discuse, of the wings as organs of locomotion, the wing skeleton becomes reduced in length; each segment of the wing is reduced, but the degree of reduction is greatest in the more distal segments. It is probable that reduction appears first in the most distal segment and later successively in each segment proceeding proximally therefrom.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1050630202
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  • 20
    Electronic Resource
    Electronic Resource
    The absorptive processes in the embryos of Parabrotula dentiens, a viviparous, deep-sea Brotulid fish (1936)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 59 (1936), S. 313-325 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Parabrotula dentiens is a viviparous deep sea Brotulid fish. The embryos at the 6 mm. stage are held within the ovarian cavity as are the embryos of Zoarces, the Embiotocidae, the Goodeidae, the Jenynsiidae and the Anablepidae in the later stages. The embryos of Parabrotula dentiens are equipped with external processes which are attached around the anus and to the ventral wall of the embryo for a short distance in front of the anus. The processes have a spongy connective tissue stroma and are covered with a syncytial layer. It is assumed that the processes augment the body surface of the embryos and have a nutrition-absorbing and an oxygen-absorbing function.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1050590205
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