ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • Life and Medical Sciences  (40)
  • 1950-1954  (6)
  • 1935-1939  (34)
  • 1953  (6)
  • 1937  (13)
  • 1936  (11)
  • 1935  (10)
  • 1
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Journal of Morphology 57 (1935), S. 131-145 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: A hitherto unknown secondary sex character in male frogs consists of a series of connective tissue bands which extends the entire length of both layers of the Obliquus muscle, at both their dorsal and ventral borders. Extensions of the ventral bands may be carried inward toward the midline at certain of the inscriptiones tendinae. These bands are named the Lineae masculinae. They are clearly visible in specimens from which the skin has been removed, and are visible even through the skin in living specimens of certain species of Kaloula.Ninety-one genera and 553 species of the frogs and toads of the world were examined for the presence or absence of this structure. It is distinct in the common American and European ranids, such as Rana pipiens and Rana esculenta. It is entirely absent in many genera. When present it is found only in adult males, being absent in sexually immature males and females of all ages. Examination revealed no seasonal variations in males of Rana pipiens. This indicates that there is some correlation between the expression of this character and the sexual hormones. No function is assigned to the Linea masculina, although it is suggested that it may be associated in some way with voice production. A discussion of the taxonomic distribution of the character is included.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Journal of Morphology 93 (1953), S. 301-329 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Additional Material: 5 Tab.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    Electronic Resource
    Electronic Resource
    Philadelphia : Wiley-Blackwell
    Journal of Cellular and Comparative Physiology 6 (1935), S. 387-391 
    ISSN: 0095-9898
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    Electronic Resource
    Electronic Resource
    Philadelphia : Wiley-Blackwell
    Journal of Cellular and Comparative Physiology 10 (1937), S. 365-383 
    ISSN: 0095-9898
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Additional Material: 5 Tab.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Journal of Morphology 60 (1937), S. 445-458 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: A description is given of the gross anatomy of the tracheal system of the larva of Drosophila melanogaster. Comparisons of findings are made with those of Lowne for Calliphora, Wahl for Eristalis, Simms for Hylemyia, Dufour for Sarcophaga, Wandolleck for Platycephala, Trägårdh for Ephydra, and De Meijere for Lonchoptera.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 6
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Journal of Morphology 61 (1937), S. 495-523 
    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
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 7
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Journal of Morphology 61 (1937), S. 563-579 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: This paper correlates the various aspects of the author's previous work on embryonic columnar epithelia and deals especially with the mechanical factors that determine the form of an epithelium. The origin of the terminal bars, the various forms the terminal bars assume, and the significance of the terminal bar net in maintaining the epithelial structure are discussed. The paper also gives detailed consideration to the elongation of columnar cells after division. When this change in shape cannot be attributed to crowding from without, it is suggested that a thrusting action of elongating spindle fibers is the internal force responsible. In either case elongation is influenced by the development of the terminal web limiting the free surface. Further observations on this structure, first described by the author in 1935, are presented. The terminal web, which is generally present in columnar epithelia, is a specialized part of fixed cytoplasm, condensed, and lying in the plane of the terminal bars. It disappears in mitosis, but its reappearance as the new cell elongates limits the area of the free end of the cell. Hence, the terminal web plays an important part in determining the form of columnar cells.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 8
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Journal of Morphology 60 (1936), S. 1-11 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Nuclei of columnar epithelia of vertebrate embryos move to the free epithelial surface before a division, the movement of the nucleus accompanying a shortening of the columnar cell. After division at the free surface the daughter cells elongate, the nuclei passing away from the free surface. This is illustrated by drawings and measurements of cells of the fore-gut it of the garter snake embryo. The elongation of these cells after mitosis is associated with an elongation of the spindle fibers to produce a prominent cytoplasmic fiber which persists through the interkinetic stage and into the next mitosis. The appearance of nests of nuclei in mitosis is accounted for by the fact that descendants of an earlier cell have kept approximately in step in their divisions.
    Additional Material: 11 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 9
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Journal of Morphology 60 (1936), S. 261-277 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: A study has been made of 155 Lebistes embryos, extending from fertilization until birth of the young. A period of embryonic hermaphroditism begins soon after the formation of the genital ridges (3.0 mm.) and continues until birth (6.5 to 7.0 mm.). Development is first ovarian; evidence is the universal occurrence, in all gonads, of many germ cells in typical ovarian synapsis. The gonads of one-half of the embryos soon become testicular while those of the other half continue to develop as ovaries. In testicular gonads, all synaptic germ cells undergo pycnotic dissolution as the gonad hilus organizes into a prospective medulla. In ovaries, germ cells in synapsis continue to enlarge as definitive ovocytes. This embryonic hermaphroditism supports Witschi's explanation of sex determination in Lebistes, based on his own work on frogs and on Winge's discovery of unusual XX males in Lebistes. The embryology of gonads in Lebistes also suggests that in teleosts, as in amphibians, birds, and mammals, gonads develop from two distinct portions, a male medulla and a female cortex.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 10
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Journal of Morphology 60 (1937), S. 393-405 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The epididymis in the male bird consists of the rete testis, ductuli efferentia, and epididymal tubules. The rete testis is lined with cuboidal epithelium not resting on a basement membrane. When distended with sperm the epithelium appears squamous-like. The tubuli efferentia are lined for the most part with pseudostratied ciliated columnar epithelium resting on a basement membrane. The epithelium is thrown into permanent longitudinal ridges. The epididymal tubules are lined with ciliated columnar epithelium resting on a bastment membrane.The three types of genital ducts are intermingled to some extent, but maintain a definite sequence in their connection with one another. The rete testis drains into the tubuli efferentia, and the latter into the epididymal tubules. These drain into the vas deferens.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...