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Microarchitecture of the cat testis with special reference to Leydig cells. A three-dimensional study by alkali maceration method and scanning electron microscopy.
No full textThis paper describes for the first time the three dimensional organization of Leydig cells in the adult cat. Samples were obtained by castration of inpatients of a University clinics. Testis were macerated with NaOH in order to study either the cells as well as the extracellular matrix of the testis. Leydig cells showed between them a fine canalicular-like system formed by microvilli; this arrangement may favor passage of hormones and growth factors. Collagen fibers, in turn, formed a real three dimensional scaffold around seminiferous tubules and in the testicular lamina propria
Studio al microscopio elettronico a scansione sui rapporti tra apparato vascolare e muscolare nella salpinge di coniglio
No full textThe Ultrastructure of the myosalpinx in guinea pigs, rabbits, and humans as revealed by scanning electron microscopy
No full textPored domes in adrenocortical capillaries. An ultrastructural study in mammals
No full textThe adrenocortical gland is one of the most vascularized organs of the mammalian body. It undergoes continuous morphological changes dynamically dependent upon special permeability conditions related to various physiological and physiopathological events. The adrenal cortex of different adult mammals (3 pigs, 2 mice, 3 sheep) was studied by means of scanning (SEM) and transmission (TEM) electron microscopy. As seen by SEM it is formed of polyhedral cells which delimit a characteristic continuous labyrinth system of intercellular lacunae occupied by sinusoid-like capillaries. The capillary wall is fenestrated and is lined by flattened endothelial cells with their nuclear part bulging into the capillary lumen. The fenestrae are round or oval pores measuring 50-100 nm in diameter. They are usually clustered to form sieve plates and characteristically present a thin membranous diaphragm. Irregular microelevations and dome-like projections are often seen. These structures are made of thin cytoplasmic plates interrupted by numerous small pores which show a sieve plate profile. The pored-domes on the nuclear portion seem to be identical in structure to those found in the thinner endothelial part; some of them appear to detach from the endothelial cell. The pored-domes are structurally comparable to those reported both in the renal glomerular endothelium and in liver sinusoids. These endothelial structures may be an expression of the high rate of filtration of these tissues and may be also related to the final step of the replacement of the sieve plates during endothelial regeneration
Lo scheletro fibromuscolare del corpo luteo. Eleborazione di un modello esemplificativo tridimensionale
No full textThe collagen skeleton of the cat testis. A scanning electron microscopy study after 2N-NaOH maceration.
No full textTestes from adult cats were studied by means of scanning electron microscopy (SEM) after 2N-NaOH maceration method which selectively digests cells and tissue compounds. As seen by this technique, the testis appears covered by a dense fibroconnective tunica albuginea that divides partially the organ by sending septa into the parenchyma. The interstitium is made up by a rich connective tissue composed by randomly-arranged fine collagen bundles that clearly outline the spaces occupied by the seminiferous tubules. The basement membrane of the seminiferous tubules consists in two rough layers of collagen fibers that in some places leave small fenestrations. The three-dimensional arrangement of collagen fibers in the interstitium outlines a system of cavities likely to be lacunar spaces for Leydig cells and vascular imprints. Especially, the above chemical technique followed by deep observations under the SEM allowed a clear and complete view of the real three-dimensional microarchitecture of the connective tissue of the testis. Therefore, the collagen component was revealed to actually form a unique and complex skeleton for the whole organ. This three-dimensional figure closely follows indeed the classical histological compartmentalization of the testis with a better insight of its spatial microtopographical features. Moreover, this structural pattern is also likely to give rise to very fine morphofunctional subcompartmentalization, especially regarding the basement membrane of the seminiferous tubules and the lacunar spaces for Leydig cells including satellite vessels
The three-dimensional architecture of the human myosalpinx. A new morpho-functional model
No full textThree-dimensional architecture of the human myosalpinx isthmus. Scanning electron microscopy after NaOH digestion and ultrasonic microdissection
No full textThe three-dimensional architecture of the human isthmic myosalpinx is directly
visualized by means of scanning electron microscopy after removal of interstitial
connective tissue through NaOH maceration and ultrasound microdissection. These
investigations show that the myosalpinx is composed of irregularly running
bundles of smooth muscle cells, changing their orientation within the myosalpinx
and displaying longitudinal, oblique and circular directions. The muscular
bundles anastomose and intermingle with other bundles running at different levels
in the oviduct wall, and actually give rise to a wide and complex muscular
network in which no distinct layers are readily discernible. These morphological
data are consistent with the physiological findings that the transport of gametes
and embryo in very early stages in the isthmic portion of the oviduct tube is the
result of a discontinuous pattern of forward and backward movement
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