الفهرس 
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Abstract
layer and auter loose one. Collagenous
and elastic
fibers
~he presen~ s~udy has revealed that the paramesonephric ducts
are the primordial
s t r uc t ur-e s
irom which ~he u~erus
lped. They begin to develop in the 35 days old embryo as
)w epi~helial invaginations
at the cranial
poles of
-::he
sphr o t . In 38 days old embrvo,
~heir grow~h level
has
led -;:0 abou~ -::he biginning of the caudal
third of
”the
-phr oa . During the 2nd developmentalmorrt n , the growth of ::he
lad extended beyond the mesonephroi and they beEin to
f us e
19 the uterine body and the uterovaginal primordium which
lue its caudal growth to reach the urogenital
sinus by -::he
,ay. Uterine differentiation began its initiation during the
veloomental month. At ~his period ~he uterine wall of -;:he
nd horns was comprised of; an epithelial lining of densely
cells resting on thin,
even
basal
lamina
and
a
thelial layer of undifferentiated mesenchyme. By the onset
4-::h d,::.veloomental mon~h. the uterine epithelium tended
pseudostra~ified
columnar
type.
The
subepi-::helial
hymal layer was made up of two distinct layers
3n inner
n~irelv absen~. By -::he day 110, the outer mesenchymal
layer
ted some differen~iated’ fibroblasts and by the end of this
small bundles of collagenous
fibers
were encoun~ered.
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Through the 5th month, the wall of the uterine horn and body
exhibited a circular band of developing myoblasts between the
inner and outer mesenchymal layer. Accordingly. the uterine wall
appeared to be formed of inner mucosa. middle muscular layer and
an outer serosa. By the end of the 5th month.
the caruncles
initiated their development as shallow epithelial invaginations
penetrating thG underlying stroma.
Through the 6th month,
-:he
uterine lumen irregularity was gradually increased
due
progressive epithelial invaginations, forming 3 or 4 epithelial
clefts. consequently the uterine mucosa appeared to be organized
of raised circumscribed areas separated by deep clefts forming
nodular and internodular areas. At the last week of the 6th month.
the inter nodular clefts showed basal branches extending in a
direction parallel to the summit of the nodular area. The propria
submucosa was still of primative
mesenchymal
nature.
The
myometrium was slightly increased in thickness. from the 7th to
the 10th month, the polymorphic uterine nodules were graduall:!
increased in size and protruded more into the lumen. The
myometrium showed progressive increase in thickeness being formed
mainly of circularly arranged smooth muscle fibers and an outer.
comparatively thin,
logitudinal layer.
was
The
perimetrium
differentiated into loose connective tissue layer with an outer
mesothelium. By the end of the 10th developmental month. the
uterine glands primordia were firstly observed as short epithelial
downgrowths from the bases and sides of the intercaruncular areas
into the underlying stroma. The fetal myometrium and perimetrium
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showed ~he normal developmental growth related to gradual increase
in thickeness as a resul~ of the proliferation
of
their
components.
Cervix :
The cervix was firstly recognized in ~he caudal fused part of
~he paramesonephric ducts a~ about the middle of the 3rd
developmental month. At this age, the cervical mucosa was slightly
folded and the cervical wall consisted of lamina epithelialis
surrounded by exclusively cellular mesenchymal layer.
Within the
latter layer,
small isolated bundles of smooth muscles were
noticed dividing it into an inner layer representing the future
propria-submucosa and an outer one representing the serosa.
Through the 4th month, the folding process was continued and the
cervical epithelium showed some areas of pseudostratification. The
epithelial cytoplasm showed considerable amount of
glycogen
granules and marked reactivity to PAS. By the begining of the 5th
month, the cervical mucosa appeared organized of large, number of
short, comparatively wide folds. The propria-submucosa showed ~he
presence of several epithelial sinuses which were encountered
throughout the succeeding developmental stages. The muscular layer
was slightly increased in thickness and by the end of the 5th
month, i~ was organized into an inner circular and thin ou~er
longitudinal layer. The inner circular layer has been given off
cental or bilateral ramifica~ions into the cores of ~he major
cervical folds. At the begining of the 6th month,
the cervical
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mucosa was ~hrown into large primary folds superficially divided
were evident along the entire length of the cervix.
At the
into smaller ones. By the end of this month.
two annular rings
begining of the 7th month, folding and branching of the cervical
muscosa wa~ advanced with a substantial reduc~ion in the width of
the lumen. During the 8th months, the large primary cervical folds
were equipped with secondary and tertiary folds and goblet cells
were noticed among the epithelial lining. Through the 10th month,
the elaborately folded cervical mucosa had reached its full
expression. The cervical epithelium became mostly simple columnar
or cuboidal by the end of this month. The propria-submucosa showed
a gradual relative increase in the number of fibroblasts
collagenous and elastic fibres and by the end of the 10th month it
was looking like loose connective tissue. The muscular layer has
been extensively thickened and became composed of 4 or 5 inner
circular and one outer longitudinal layers of smooth muscle cells.
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