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Nuove acquisizioni microanatomiche sulla fisiopatologia tubarica e loro risvolto sul trattamento chirurgico dell'infertilità tubarica.
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
Cellular and microvascular changes of the ovarian follicle during folliculogenesis: a scanning electron microscopic study
No full textIn order to study the three-dimensional topographic arrangement of the oocyte and
zona pellucida, follicular cells and follicle microvasculature, this study
applied alkali maceration methods for tissue exposure, the ruthenium
red-detergent method for the extracellular matrix visualization, and the vascular
corrosion cast technique to rabbits, guinea-pigs and mice ovaries at different
stages of follicular development. Macerated samples showed a gradual
differentiation of the oocyte surface. This, in primordial follicles, appeared
rather smooth, but, with the follicular development, displayed a gradual increase
of blebs and microvilli. The latter widely covered the surface of oocytes
contained in large or mature follicles. The outer surface of the zona pellucida
showed numerous fenestrations, whereas the inner one was smooth. The ruthenium
red-detergent method permitted a well detailed view of the filamentous texture of
the zona pellucida. The three-dimensional distribution of the contacts between
oocyte and neighbouring follicular cells was clearly evaluated in macerated
samples. Follicular cells of primary follicles were characterized by their short
cytoplasmic processes reaching the oocyte surface. In secondary follicles, these
processes issued secondary processes. In larger follicles, the secondary
processes of the corona cells were much longer and thinner, and took a tortuous
course to reach the oocyte surface, which ran among the numerous oocyte
microvilli. This microvillous arrangement greatly increases contact between the
oocyte and corona cells, and suggests a coordinated reciprocal control of the
activities of both cell types. These data also showed that the spongy and
filamentous nature of the zona pellucida is closely dependent upon the temporal
differentiation and enormous increase in number of follicular cell projections
and their ramifications. Maceration revealed the theca cells surface. In smaller
follicles these appeared as fusiform cells which resembled fibroblasts. In larger
or mature follicles, many theca cells differentiated to possess morphological
features of steroidogenic cells. In addition, these cells delimited a series of
intercellular communicating lacunae, continuous with wide pericapillary spaces.
The gradual differentiation of the follicle towards a structure having an
endocrinal role was further emphasized in vascular corrosion casts. A simple
microvascular net made of thin capillaries supplying primary follicles was seen
to transform into an elaborate sinusoidal network made of thick permeable
capillaries, supplying mature follicle
Hilar vessels of the ovary as seen by scanning electron microscopy of vascular corrosion casts
No full textStudio al microscopio elettronico a scansione sui rapporti tra apparato vascolare e muscolare nella salpinge di coniglio
No full textChanges of ovarian microvasculature in hCG stimulated rabbits. A scanning electron microscopic study of corrosion casts
No full textThe microvasculature of the ovarian cortex was studied by means of scanning
electron microscopy of vascular corrosion casts in estrous and hCG stimulated
rabbits in order to establish a better understanding of the structural as well as
functional vascular changes which accompany the evolution of the luteofollicular
complex. According to the various shape and size seven different morphological
types of vascular plexuses corresponding respectively to antral follicles (Types
1-2), atretic follicles (Types 3-4), periovulatory follicles (Type 5), growing
pseudopregnant corpora lutea (Type 6) and regressing pseudopregnant corpora lutea
(Type 7) were identified. Growing to mature cycling type follicles (Types 1-2)
showed a gradual enlargement and proliferation of the theca capillaries. These
changes, associated with capillary hyper-permeabilization were observed in
ovulatory and post-ovulatory follicles (Types 5), after hCG stimulation. The
corpus luteum formation (Types 6) was accompanied by additional capillary
dilatation, diffuse angiogenetic sprouts and organization of a more conspicuous
venous drainage. The regression of the corpus luteum (Type 7) was characterized
by the appearance of avascular areas within the glandular tissue and by
regression of vascular dilatation. The atretic follicle (Types 3-4) wall showed
large interruptions (avascular areas) and focal invasion of the central cavity by
newly formed capillaries randomly arranged. The hCG stimulation did not affect
consistently the atretic follicle microvasculature. The present observation shows
that both thecal capillary vasodilatation and angiogenetic processes support the
gradual increase of ovarian blood flow during follicle growth and corpora lutea
formation and that microvascular changes of atretic follicles are possibly
related to a type of inflammatory reaction since they seem to be a consequence
rather than a primary cause of atresi
La rete fibrillare collagene della vena safena umana normale [Collagenous structure of human safenous vein]
No full textConvegno Nazionale della Società Italiana di Anatomia, Santa Margherita Ligure, 4-7 Ottobre 199
Microvascolarizzazione della colecisti. Studio al Microscopio Elettronico a Scansione di calchi microvascolari
No full textComment: Survival rate comparisons amongst cervical cancer patients treated with an open, robotic-assisted or laparoscopic radical hysterectomy: A five year experience
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