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  • 1
    Publication Date: 2013-06-12
    Description: The subcellular behavior of several mineral elements was studied using modern techniques of observation like transmission electron microscopy and analysis like electron probe microanalysis and secondary ion mass spectrometry. In the present ultrastructural and analytical investigations, we undertake to compare the intracellular behavior of a heavy metal, gold, and a III-A group element, indium, on rat testicular tissues after their parenteral administrations. Our ultrastructural results showed that while gold was found only in the lysosomes of Leydig cells under electron dense needles, indium was observed as electron-dense deposits in the lysosomes of both Leydig and Sertoli cells. No ultrastructural modifications were observed in the testicular tissues of the control rats. The microanalytical study showed that gold was concentrated in lysosomes with sulfur as a sulfate crystalline structure whereas indium was concentrated in the same organelle as insoluble phosphate salt. These results demonstrated that testicular Leydig and Sertoli cells have the ability to selectively concentrate indium but gold was concentrated only in the first kind of cells. The mechanism implicated in this concentration phenomenon is a biochemical one involving intralysosomal hydrolytic enzymes, the acid phosphatase and the arylsulfatase. This mechanism occurs in order to protect the organism and to avoid the presence of toxic metals under soluble and free form.
    Print ISSN: 0022-0744
    Electronic ISSN: 1477-9986
    Topics: Electrical Engineering, Measurement and Control Technology , Natural Sciences in General , Physics
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  • 2
    Publication Date: 2011-04-01
    Print ISSN: 0022-0744
    Electronic ISSN: 1477-9986
    Topics: Electrical Engineering, Measurement and Control Technology , Natural Sciences in General , Physics
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  • 3
    Publication Date: 2021-05-19
    Description: Dans cette étude, nous nous sommes intéressés à la détermination des différents stades du développement gonadique chez le mollusque gastéropode: Patella caerulea prélevé au niveau de la station Canal de Bizerte située sur la côte nord de la Tunisie en nous basant sur les techniques d'histologie classique de la gonade. Cette étude s’est déroulée sur une période allant de mars 2006 à août 2007 et a porté sur 552 spécimens de longueur comprise entre 20,73 et 45,14 mm (± 4,59 mm). L’étude de la sex-ratio a montré une nette dominance des mâles par rapport aux femelles. L’activité gonadique a démarré en août/septembre pour les deux sexes. Chez les mâles, une émission principale des gamètes a eu lieu entre mai et août 2006 et entre avril et juillet 2007. Pour les femelles, l'émission principale des gamètes s'est produite entre le mois de d’avril et le mois de juillet des deux années 2006 et 2007. Toutefois, une émission partielle des gamètes en relation avec les variations des facteurs environnementaux, a été observée durant la saison hivernale chez les deux sexes.
    Description: يقدم هذا العمل مختلف مراحل نمو الغدد التناسلية عند فصيلة معديات الأرجل (Patella caerulea) التي تم التقاطها على مستوى قنال بنزرت (شمال تونس) وذلك خلال الفترة من مارس 2006 إلى أوت 2008 أثبتت هذه الدراسة أن عدد الذكور يفوق عدد الإناث على مدى فصول السنة. و قد تم الاعتماد على دراسة الغدد الأنسجة حسب تقنيات علم الأنسجة. بينت هذه الدراسة انطلاق مرحلة نضج المشيجات إبتداء من شهر أوت/سبتمبر بالنسبة للجنسين. عند الذكور, ظهرت مرحلة التفريغ الأساسية خلال الفترات المتراوحة بين أشهر ماي و أوت ٢٠٠٦ و بين أفريل و جويلية ٢٠٠٧. أما بالنسبة للإناث, ظهرت هذه المرحلة خلال الفترات المتراوحة بين أشهر أفريل و جويلية للسنتان المتتاليتان غير أنه لاحظنا ظهور مرحلة تفريغ ثانوية ناتجة للتغيرات العوامل البيئية خلال فصل الشتاء و ذلك بالنسبة للجنسين.
    Description: This study devised a staging system for the gonad development of the limpet Patella caerulea on the northern coast of Tunisia using histological techniques. This study took place over a period from March 2006 to August 2007 and focused on 552 specimens of length between 20.73 and 45.14 mm (± 4.59 mm). Sex ratio varied along the study period, with samples always presenting more males than females. Maturation began in August / September for both sexes. In males, spawning took place from May to August 2006 and from April to July 2007. Regarding females, spawning took place from April to July for both consecutive years. However, a secondary spawning peak related to the variations of the environmental factors was observed during the winter season for both sexes.
    Description: Published
    Description: Patella caerulea, développement gonadique, émission gamétique, Tunisie
    Keywords: Molluscs ; Reproduction
    Repository Name: AquaDocs
    Type: Journal Contribution , Refereed , Article
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