Library

feed icon rss

Your email was sent successfully. Check your inbox.

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

Proceed reservation?

Export
  • 1
    ISSN: 1572-8773
    Keywords: Cadmium resistance ; Drosophila midgut ; Lysosomes ; Electron-probe microanalysis ; Metallothionein
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Summary The midgut of a cadmium-resistant strain ofDrosophila melanogaster has been studied at the ultrastructural level and by electronprobe microanalysis (EPMA). Chronic exposure to cadmium leads to a concentration of the metal in a lysosomal system developed in both anterior and posterior segments of the midgut, where it coexists with copper and sulfur. This mechanism apparently ensures a permanent cadmium detoxification and prevents cellular injury. Wild-type flies fed on a cadmium-contaminated medium manifest the same detoxification process. As a result of contamination, copper is stored along the entire length of the midgut, including a part of the middle-midgut previously named ‘copper-accuumulating region’. Our data demonstrate that the midgut, particularly the posterior segment, is an accumulative organ for both cadmium and copper. The involvement of the metallothionein system in the detoxification process is discussed.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Cell & tissue research 133 (1972), S. 163-179 
    ISSN: 1432-0878
    Keywords: Excretory organ ; Ileum ; Blatella germanica ; Ultrastructure ; Microprobe analysis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Résumé L'iléon de Blatella germanica est un important segment d'accumulation minérale. Les nombreuses concrétions d'origine ergastoplasmique, contiennent du phosphore, du chlore, du calcium, du magnesium, du potassium et du fer dans un stroma glycoprotéique. La paroi de ce segment protodéal est constituée d'un type cellulaire unique caractérisé par la présence de feuillets apicaux et d'invaginations basales, différenciations membranaires décrites dans d'autres organes de transit, mais dont la coexistence constitue l'originalité de l'iléon. La signification physiologique de ce segment digestif est discutée.
    Notes: Summary The ileum of Blatella germanica is an important proctodeal segment of mineral accumulation. The numerous concretions, elaborated by the ergastoplasm, contain P, Cl, Ca, Mg, K and Fe in a glycoproteic matrix. The epithelium of this segment is composed by only one type of cells which are characterized by apical leaflets and basal infoldings. These membraneous differenciations have been already described in other transit organs, but their coexistence is typical of the ileum. The physiological significance of this digestive segment is discussed.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    Electronic Resource
    Electronic Resource
    Springer
    Cell & tissue research 109 (1970), S. 336-355 
    ISSN: 1432-0878
    Keywords: Excretory organs ; Male accessory glands ; Insects ; Blatella germanica ; Cytophysiology
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Résumé Les utricules, glandes annexes de l'appareil génital mâle deBlatella germanica, constituent un organe à la fois excréteur et sécréteur. Ils comportent un épithélium simple, formé d'un seul type de cellules qui cumulent ces deux fonctions. Le réticulum endoplasmique a un rôle primordial dans l'élimination des substances provenant de l'hémolymphe et qu'il transporte vers la lumière sous forme dissoute ou après cristallisation. L'excrétion des urates s'effectue en moins de 15 mn, la cristallisation en moins de 3 h. Les sphérocristaux sont constitués de plusieurs couches concentriques. Ils contiennent des urates et divers ions: Mg, K, Ca, P, Na, Cl, S et Cu. La structure et la fonction des utricules sont comparées à celles des tubes de Malpighi, la composition ionique des cristaux à celle de cristaux d'autres organes d'excrétion ou d'accumulation.
    Notes: Summary The Utricules, male accessory glands ofBlatella germanica are both excretory and secretory organs. They are formed by a simple epithelium composed of one type of cells which performs those two functions. The endoplasmic reticulum plays an important role in the elimination of substances — either in solution or crystallized — from the haemolymph. The excretion of urates is initiated in less than 15 mn, crystallisation in less than 3 h. The concretions include numerous concentric strata which contain uric acid and a number of ions: Mg, K, Ca, P, Na, Cl, S, and Cu. A morphological and physiological comparison has been envisaged between the Utricules and the Malpighian tubules; also the ionic constitution of the concretions is compared with the composition of other excretory or accumulatory organs.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...