摘要:

AbstractIn sections of thymus stained with the tannic acid‐phosphomolybdic acid‐amido black (TPA) technique, the epithelial reticular cells can readily be identified by the well‐stained tonofibrils in their cytoplasm. In the cortex, flattened epithelial reticular cells form a continuous layer on the inner surface of the capsule and along the interlobular septa. Within the cortex proper, stellate epithelial reticular cells are widely dispersed as a loose network. In the medulla, two zones, referred to as “outer” and “inner” medulla, are distinguished. The outer medulla, like the cortex, contains epithelial reticular cells, but these are more voluminous, are more richly provided with tonofibrils and form a denser network than in the cortex. In the inner medulla no epithelial reticular cells can be seen but instead connective tissue cells and fibers make up the supporting framework. A layer of flattened epithelial reticular cells demarcates the outer from the inner medulla. This layer of cells also extends along the outer surface of blood capillaries seen in the outer medulla and cortex. Around the larger blood vessels, this layer of epithelial reticular cells is separated from the vessel wall by a connective tissue perivascular space. Hence, the inner medulla is continuous with the perivascular spaces and, like them, is supported by connective tissue. Thus, the epithelial reticular cells constitute the supporting framework of the cortex and outer medulla and separate these regions from the connective tissue of the capsule, interlobular septa, blood vessels and

ISSN:0003-276X    

DOI:10.1002/ar.1091690402

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1971

数据来源: WILEY

摘要:

AbstractThe left adrenal in adult coyotes (25) was heavier than the right (P0.05). Absolute adrenal weight in adult females was greater than in adult males (P<0.01). In the six pups which were under seven months old the adrenals of males were heavier than in females (P<0.025).Changes in the widths of adrenocortical zones were analyzed with regard to maturity. The width of the glomerular zone in immature coyotes was not different from mature animals. Immature males had a wider fasciculata than immature females (P<0.01) and mature males (P<0.01). The reticular zone exhibited the greatest relative growth with maturity in both sexes.Zona glomerular cells were columnar epithelia with oval nuclei which contained one or two nucleoli. Fascicular cells were polyhedral shaped with central nuclei which contained as many as three nucleoli. The zona reticularis was characterized by anastomosing cords. Nuclei were highly variable in size. Nucleoli were often dispersed around the nuclear membrane. Lipids were stored as large irregularly‐shaped droplets in the fasciculata and as small, round droplets in the reticularis.Cortical cells from coyotes of all ages showed the presence of histones; all zones reacted positively. Nucleoli and chromatin granules gave intense reactions, suggesting close association between histones and nuclear RNA and DN

ISSN:0003-276X    

DOI:10.1002/ar.1091690403

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1971

数据来源: WILEY

摘要:

AbstractPituitary glands of 30 ♀ rats from one to seven and one‐half months old were fixed in glutaraldehyde followed by osmium tetroxide. One five‐month gland was fixed in Karnovsky's paraformaldehyde mixture.Cilia in the residual cleft at all ages and in the electron lucid vesicles found in the pars distalis during the first two months occur in great numbers per cell and show the 9 + 2 pattern (9 peripheral doublets around 2 central tubules slightly separated from each other) characteristic of kinocilia. The spaces into which these cilia project may contain disintegrating cells as well as colloid‐like material of variable density.Cilia found in or between parenchymal cells of the pars distalis usually occur one per cell and lack central tubules. One of the doublets is often displaced toward the center. Cilia have been seen in three types of granular as well as in non‐granular cells. A pair of cilia enclosed in the same membrane was found once within and twice between parenchymal cells.Central tubules appear to develop only in locations (cleft and vesicles) where motility is possible. The single cilia found in parenchymal cells may be considered immature and are presumably non

ISSN:0003-276X    

DOI:10.1002/ar.1091690404

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1971

数据来源: WILEY

摘要:

AbstractAn electromyographic investigation of the mylohyoid muscle was undertaken to determine its activity relative to isolated movements of the tongue and mandible and during various functions involving multiple parts of the oral apparatus. Data was obtained from 20 subjects. Using bipolar fine‐wire electrodes, the anterior fibers were found to be more active than the posterolateral fibers in a majority of activities performed. Tongue movements produced slightly more activity in the postero‐lateral fibers; the anterior fibers were more active during mandible movements. During mastication, deglutition, sucking and blowing, both the anterior and postero‐lateral fibers were markedly a

ISSN:0003-276X    

DOI:10.1002/ar.1091690405

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1971

数据来源: WILEY

摘要:

AbstractIn electron microscope examinations of leg muscles from fetal and postnatal rats the development of SR tubules precedes the development of Z lines and the formation of fibrils, thus showing that a function of SR in Z line development is possible. Early stages of fibril formation reveal very small Z lines (0.06 μ thick) which are encircled by SR tubules separated from the Z lines by a space about 100 Å wide, and this space is traversed by electron‐opaque strands which appear to be connections between SR tubules and Z lines. The encircling SR tubules are observed from the beginning to the completion of Z line development. The small Z lines contain dense lines transversely oriented between thin filament tips that resemble transversely oriented dense lines found in fully developed Z lines. It is concluded that Z line enlargement involves growth in circumference of encircling SR tubules as the tubules incorporate additional layers of thin filament tips. It is suggested that the substance represented by electronopaque strands connecting SR tubules and Z lines might provide precursors for the substance represented by transversely oriented dense lines between thin filament t

ISSN:0003-276X    

DOI:10.1002/ar.1091690406

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1971

数据来源: WILEY

摘要:

AbstractRecent data indicate active transport of Na+and K+by the main excretory duct (MED) of the rat submandibular gland. In view of these data submandibular MED's of four adult rats were investigated by transmission electron microscopy. Luminal surfaces of two MED's were examined with the scanning electron microscope. The duct is surrounded by connective tissue, blood vessels and neuron perikarya. Blood supply to the ductal epithelium consists of a plexus of sinusoidal capillaries. Three principal cell types compose the epithelium: light cells, dark cells, and basal cells. The basal cells resemble those of striated ducts except for the presence of numerous hemidesmosomes along basal plasma membranes of MED basal cells. Light cells show basal infoldings, and bulbous enlargements may occur at their distal aspects. Dark cells are narrow, electron dense cells with prominent microvilli at the luminal surface. Intercellular clefts penetrate MED epithelium from the lumen to a depth of one‐third the epithelial thickness. Surfaces of the clefts are lined by dark and light cells. Intercellular tissue spaces are present at lateral boundaries of all cells and extend from the epithelial base to distal cytoplasmic level

ISSN:0003-276X    

DOI:10.1002/ar.1091690407

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1971

数据来源: WILEY

摘要:

AbstractThe intermediate root of the trigeminal nerve in the dog has been investigated both macroscopically and microscopically. Sixty‐two trigeminal complexes (trigeminal ganglion, trigeminal roots and the portion of the pons to which the roots were attached) in the dog were dissected out and removed. Each of the complexes was fixed in 10% formalin, dehydrated and embedded in paraffin. The paraffin blocks were cut serially at 10 μ. Every other slide was either stained with Luxol Fast Blue or impregnated with Bodian's silver method. In all cases, between the motor and sensory roots an intermediate root composed of one distinct rootlet was identified. Most frequently the intermediate root was attached to the pons from 0.5 to 3.0 mm lateral to the motor root and rostral to the sensory root from 0.5 to 2.0 mm. From its pontine attachment the intermediate root extended anteromedially for a distance of from 2.0 to 5.0 mm before it became incorporated in the lateral aspect of the free motor root. Closer to the trigeminal ganglion the motor root and the intermediate root fused with the expanding sensory root. The fibers in the intermediate root ranged from 1.5 to 7.5 μ in diameter with the majority of fibers (60 to 70%) having a diameter of from 4.0 to 6.0 μ. Approximately 10% of the fibers were unmyelinated. The total number of fibers in the intermediate root varied from 170 to 416 with an average of 266 fibers. The morphological data obtained in an experimental animal such as presented in this paper may provide a basis for future experimental work on the clarification of the functional role of the trigeminal intermediate

ISSN:0003-276X    

DOI:10.1002/ar.1091690408

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1971

数据来源: WILEY

摘要:

AbstractThe cartilage plates covering the lumbar vertebral bodies were examined macro‐ and microscopically in infants and children. Particular attention was given to the distribution of vascular canals within these plates. Some of the canals are responsible for the formation of spoke‐like ridges of cartilages. The latter develop as the vertebral body expands in height and girth. The canals show a characteristic distribution and end blindly in the neighborhood of the anulus fibrosus.The cartilage plates are known to provide a growth zone for the center of the vertebrae. In addition, they appear to contribute also to the growing intervertebral disc. The present investigation suggests that an association exists between the blind endings of the vascular canals and the interstitial lamellar growth of the anulus fibrosus at the time of active, postnatal disc expansion.Comparison of differences in shape of infantile lumbar vertebrae were made in various cases with a known history. These studies suggest that weight bearing and movement influence the development of a particular shape. It can be demonstrated that in the absence of normal stresses some lumbar vertebrae grow taller and have a decreased anterior‐posterior dia

ISSN:0003-276X    

DOI:10.1002/ar.1091690409

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1971

数据来源: WILEY

摘要:

AbstractGlycogen localization in the myometrium and luminal epithelium of the rat uterus was studied by the periodic acid‐leucofuchsin technique after ovariectomized rats had been treated with various regimens of 1.0 μg estradiol dipropionate and 50.0 μg clomiphene citrate. Three regimens were used: (a) one or three dosages of clomiphene, alone or in combination with one or three dosages of estradiol; (b) a single dosage of clomiphene before a single dosage of estradiol; (c) a single dosage of clomiphene after a single dosage of estradiol.The estrogenic effect of clomiphene on the myometrium was less than that of estradiol. Clomiphene suppressed myometrial glycogen accumulation induced by estradiol when administered with estradiol, six hours before the hormone, or as long as 24 hours after estradiol. The luminal epithelium responded differently to estradiol and clomiphene: the number of luminal epithelial cells containing glycogen strikingly increased after clomiphene treatment but not after estradiol treatment. A few scattered cells contained glycogen 24 hours after one dosage of the drug. Forty‐eight hours after a single dosage or after three dosages of the drug administered one per day, every luminal epithelial cell contained glycogen. The effect of clomiphene on the luminal epithelium may be either a unique action of the drug or an abnormal response of the tissue, similar to that reported for high doses of estradiol. This effect of clomiphene on the luminal epithelium may possibly be a factor in the drug's ability to block blastocyst implantation in th

ISSN:0003-276X    

DOI:10.1002/ar.1091690410

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1971

数据来源: WILEY

摘要:

AbstractThis paper describes the morphology of the popliteus muscle based on the dissection of 15 human cadaver's knees. The muscle is found to have three origins: the strongest from the lateral femoral condyle is already wellknown, but there is also an important band from the fibula and a firm attachment to the posterior horn of the lateral meniscus. The femoral and fibular origins form the arms of an oblique Y‐shaped ligament, the base of which is formed by the capsule and the meniscal origins. This previously was described as a separate entity, the “arcuate ligament,” attached to the belly of the muscle, but it is not a separate ligament. Rather it is a condensation of the fibers of origin of the popliteus including those from the f

ISSN:0003-276X    

DOI:10.1002/ar.1091690411

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1971

数据来源: WILEY