bluuebunny/crossref_metadata_2025_split huggingface dataset:
Hair loss and cyst formation in hairless and rhino mutant mice
Authors: Mann Stanley J. 
Published: February 2005

AbstractStructural abnormalities begin in the integument of hairless (hrhr), hairless‐rhino (hrhrrh), and rhino (hrrhhrrh) male and female mutant mice prior to the end of the first hair growth cycle. The pilary canals begin to widen and accumulate keratin and sebaceous material. During the first catagen phase the lower internal root sheath coalesces around the terminal part of the hair shaft and abnormal club hairs form. The lower part of the external root sheath fails to follow the ascending club hair and becomes stranded in the dermis. The abnormal club hairs move above their normal anchoring position and fall out of the follicle at the end of the first growth cycle. The formation of abnormal club hairs and the loss of hair probably are related to the mispositioning of the internal root sheath. Subsequent to the loss of hair there are changes in the sebaceous glands and adipose tissue, disorganization of the peripheral neurovascular system, and the formation of cysts that are associated with either the pilary canals or with epithelial units of disorganized hair follicles stranded in the dermis. Cysts arise from proliferation of epithelial tissue; sebaceous cells are not necessary for cyst formation.Comparisons among similar and dissimilar anomalies indicate that the degree of gene action on the integument is in the following order of increased severity: hrhr, hrhrrh, and hrrhhrrh.
Effect of sodium fluoride and sodium pyruvate on palatal development in vitro
Authors: Myers Gordon S. 
Published: February 2005

AbstractExplants of the embryonic rat palate have been treated by adding sodium fluoride and sodium pyruvate to the culture medium. Fluoride, at specific concentrations, causes retardation of palatal shelf growth so that fusion does not occur during the culture period. Partial or complete fusion does occur if fluoride levels are reduced.Sodium pyruvate added to the medium advances the time of fusion of explants over that found in controls. When combined with fluoride in the medium, pyruvate can reverse the effects of fluoride on shelf growth and permit complete fusion to take place in a laige percentage of explants.The mode of action of flucride or pyruvate under these experimental conditions has not been determined. However, the known effects of fluoride as an enzyme inhibitor must be considered.
Effect of estrogen treatment on bone cortex of the young rat
Authors: Singh I. J. , Gunberg D. L. 
Published: February 2005

AbstractThirty‐day old female rats were injected with 0.2 μg of 17‐Beta‐Estradiol daily for 30 days, and sacrificed at varying intervals. Decalcified crosssections of mandible, femur and tibia were prepared and measurements were made of: (1) number of osteons in two fields, (2) average number of lamellae per osteon, (3) average Haversian canal diameter, and (4) number of non‐Haversian (primary) longitudinal canals in two ×40 microscopic fields. Pro‐longed estrogen administration resulted in (1) earlier opening of vaginal plates, (2) lower rate of gain in body weight until treatment was stopped, (3) inhibition of linear bone growth but not of bone diameter, (4) decrease in the ratio bone‐weight/body‐weight, and (5) accelerated age changes in the aforementioned histologic variables; namely, increase in the first two and decrease in the latter two histologic measurements. Regression analyses indicated that as compared to long bones, consistently more accurate estimates of age at death could be derived from mandibular histology. It was concluded that bone microstructure is a sensitive measure of the metabolic state of the organism and the quantitative histologic techniques utilized here have important applications in diagnostic pathology, anthropology and in studies of development and aging.
The fine structure of bone in the nasal turbinates of young pigs
Authors: Fetter Arthur W. , Capen Charles C. 
Published: February 2005

AbstractThe three types of bone cells in the nasal turbinates had characteristic ultrastructural features. Osteoblasts were located in areas of new bone formation and had abundant endoplasmic reticulum, prominent Golgi apparatuses, numerous vesicles, and cytoplasmic processes that penetrated the adjacent osteoid. Osteocytes had variable ultrastructural characteristics. The predominant cell filled the lacuna, had few organelles, smooth plasma membranes, and was interpreted to be a mature resting osteocyte. Some osteocytes appeared to be transitional between osteoblasts and mature osteocytes. Evidence of matrix formation was seen near osteocytes with well developed organelles, whereas osteocytes with swollen mitochondria, dense bodies and irregular plasma membranes appeared to be involved with resorption of bone. Multinucleated osteo‐clasts contained numerous mitochondria and had crystals or unmineralized collagen fibrils between folds and within vacuoles of the cytoplasmic projections forming the brush border.
Ruthenium red and violet. III. Fine structure of the plasma membrane and extraneous coats in amoebae (A. proteus and chaos chaos)
Authors: Szubinska Barbara , Luft John H. 
Published: February 2005

AbstractRuthenium violet, closely related to ruthenium red, supplements the ultrastructural knowledge of the plasma membrane complex. Amoebae throughout were handled individually with braking pipettes and were exposed to ruthenium violet alive, during fixation with acrolein and OSO4, or during dehydration. Ruthenium violet was less toxic than ruthenium red but still killed the amoebae. Conventional methods reveal a filamentous layer 2000 Å thick, an amorphous layer 150 Å thick, and a typical trilaminar plasma membrane (48 Å center‐to‐center). Ruthenium violet binds to the plasma membrane, and to the extraneous coats revealing globules in the filamentous layer. The diameter of the globules decreased according to the stage of processing at which the amoebae first encountered ruthenium violet; they were 1200 Å in diameter when amoebae were alive, 600 Å in acrolein and 300 Å in dehydration. The appearance of the filamentous layer varied when ruthenium violet was replaced by very pure ruthenium red or red containing ruthenium brown (typical of commercial ruthenium red). The globules could be demonstrated without using ruthenium dyes when amoebae were treated after fixation with uranyl acetate or phosphotungstic acid. The relationship of extraneous coats of amoebae is compared with the coats and laminae of animal tissue cells.
Fine structure of the Mongolian gerbil adrenal cortex
Authors: Nickerson Peter A. 
Published: February 2005

AbstractThe relative weight of the Mongolian gerbil adrenal is one of the largest of any animal species. The adrenal cortex of the gerbil can be divided into three major zones and one zone located between th zona fasciculata and zona reticularis. Mitochondrial cristae of zona glomerulosa cells are plate‐like, those of the zona fasciculata are tubular whereas cristae are extensively developed and plate‐like in the zona reticularis. Lipid droplets are numerous in fasciculata cells and sparse in glomerulosa and reticularis cells. Fasciculata and glomerulosa cells contain tubules of smooth endoplasmic reticulum whereas rough reticulum predominates in reticularis and border cells. Abundant lysosomes are found in glomerulosa cells; lysosomes are aggregated beneath the cell membrane of reticularis cells. Whorls of concentric lamellae of rough endoplasmic reticulum are localized exclusively to cells in the border zone. Cells in the border zone resemble those of the reticularis because of a virtual absence of smooth endoplasmic reticulum although mitochondrial cristae are tubular and therefore similar to those of the zona fasciculata. It is suggested that cells in the border zone represent a reserve of cells which may transform into fasciculata cells upon stimulation.
Ultrastructure of the junctional complexes from the descending thin limbs of the loop of Henle from rats
Authors: Bulger Ruth Ellen 
Published: February 2005

AbstractNo spaces were seen within the tight junctions of descending thin limb cells of Henle's loop in rat kidney, although spaces 70 Å in diameter and larger had previously been reported in studies utilizing rabbit kidney. Colloidal lanthanum added to the fixative solutions was not able to penetrate these rat tight junctions.
Integrated actions of the four heads of quadriceps femoris: An electromyographic study
Authors: Basmajian J. V. , Harden T. P. , Regenos E. M. 
Published: February 2005

AbstractFrom intramuscular bipolar fine‐wire electrodes in the four heads of quadriceps femoris, electromyographic recordings were made (along with electrogoniometric records) in nine normal men and women during selected postures and movements of the loaded and unloaded knee. Variation between the onset and cessation of activity between the four heads and from subject to subject was found, but the vastus medialis reflected the general pattern of activity rather than acting only terminally during extension. Rectus femoris had the shortest span of activity during extension of the knee.
Effects of x‐irradiation on lens regeneration in adult Triturus viridescens
Authors: Donaldson Donald J. 
Published: February 2005

AbstractLens regeneration was inhibited in adult Triturus v. with 1500 r of x‐irradiation. Implants of irradiated or unirradiated segments of dorsal iris were then implanted into either irradiated or unirradiated eyes. When irradiated eyes received irradiated implants, only minor degrees of lens regeneration were seen from host and implant. Unirradiated eyes receiving unirradiated implants often formed two normal lenses, one from the host and one from the implant. Irradiated eyes receiving unirradiated implants usually formed one normal regenerate arising from the implant. Unirradiated eyes receiving irradiated implants usually formed only one normal regenerate, originating from the host. The results indicate that inhibition of lens regeneration by x‐irradiation is due to effects solely on the iris, and that unirradiated neural retina, under the experimental conditions used, does not stimulate recovery of the regenerative ability of an irradiated iris. These results are discussed in relation to the question of neural‐tissue‐mediated recovery of regeneration systems from x‐irradiation.
Quantitative studies of the deep petrosal nerve of the mouse with the electron microscope
Authors: Shimozawa Atsumi 
Published: February 2005

AbstractQuantitative counts of the deep petrosal nerve of the mouse with the electron microscope have shown that, on an average, 3,208 fibers of the total nerve fibers (3,209) are unmyelinated and only one fiber is myelinated. The unmyelinated fibers in the deep petrosal nerves ranged from 0.1 to 1.7 μ in minor diameters, 0.3‐0.4 μ being most frequent (about 30% ), while their major diameters varied from 0.1 to 2.4 μ the majority being 0.4‐0.7 μ (about 60% ).
The development of sexual dimorphism in the bony pelvis of the squirrel monkey
Authors: Gingerich Philip D. 
Published: February 2005

AbstractBony pelves of mature squirrel monkeys are sexually dimorphic. They can be sexed confidently using the ratio of pubis length divided by ischium length, together with a measure of the relative width of the superior pubic ramus. Pelves of immature squirrel monkeys are not sexually dimorphic. Pelves of immature monkeys of both sexes resemble pelves of mature males morphologically. Sexual dimorphism in the pelves of squirrel monkeys is the result of female pelves acquiring morphological features at puberty which differentiate them from mature male pelves and from immature pelves of both sexes, and is not the result of male pelves being altered from immature pelves of the female type as reported for mice and rats.
Filamentous and matrix components of skeletal muscle Z‐disks
Authors: Kelly Douglas E. , Cahill Mary Ann 
Published: February 2005

AbstractThe fine structural appearance of Z‐disk lattices in vertebrate skeletal “fast” muscle varies depending upon whether osmium or glutaraldehyde has been employed as the primary fixative. Prior investigators have attributed the differences to change in the extent of actin filament overlap within the Z‐disk and/or to rearrangement of Z‐disk filaments.Adult frog and young newt “fast” muscle has been studied under various degrees of stretch, with several different aldehyde and osmium fixation procedures, and after plastic section digestion techniques utilizing Pronase or pepsin. Serial cross sections of Z‐disks were correlated with oriented cross and longitudinal sections. Fixation with collidine‐buffered osmium and veronal acetate‐buffered glutaraldehyde seems to provide the greatest and most distinctly contrasting differences. A consistently arranged phase, the filamentous lattice, can be discerned after either fixation. However, a second phase, termed “Z‐disk matrix,” appears variable, perhaps due to extraction during primary osmium fixation procedures. Glutaraldehyde‐fixed frog muscle Z‐disks display a copious matrix, one which is seldom totally depleted by osmium fixation. In young newt muscle Z‐disks, little matrix is present after glutaraldehyde fixation and none of it remains after primary osmium. In Z‐disks fixed by either method, matrix that is retained appears to be deposited in lattice‐like patterns. It is suggested that these matrix patterns, or their loss, are the basis for the varying images of Z‐disks observed under diferent fixation conditions and that the filamentous lattice is relatively stable. The Z‐disk is more rapidly obliterated by Pronase or pepsin digestion than is any other muscle component, including actin (which appears notably unreactive). The rapid digestion effect is limited to the region postulated to include the matrix phase. Models for the structural interrelationship of filamentous and matrix phases are discussed and compared to prior Z‐disk models.
Ultrastructural changes in the ependymal lining of the median eminence following the intraventricular administration of catecholamine
Authors: Schechter Joel , Weiner Richard 
Published: February 2005

AbstractChanges in the ependymal surfaces of the floor of the third ventricle and lateral recess have been studied in male rats by electron microscopy after the intraventricular administration of epinephrine or dopamine. In control rats the floor of the third ventricle has essentially a smooth contour interrupted only by occasional bleb‐like protrusions or microvilli. In the floor of the lateral recess this surface gradually becomes more irregular due to the appearance of increased surface modifications. A further increase in the number of complexly‐folded microvilli, pinocytotic vacuoles and coated vesicles occurs on the epen‐dymal surface of the roof of the lateral recess and adjacent ependyma. These morphological findings are consistent with the concept that the ependymal cells of the lateral recess may serve as important sites for the absorption of materials from the CSF.Increased numbers of bleb‐like protrusions were observed on the ependymal surface of the floor of the third ventricle five minutes after the intraventricular administration of either epinephrine or dopamine. The ependymal surface of the roof of the lateral recess also showed bleb‐like protrusions and a complexly‐folded microvillus border. Fifteen minutes after either the epinephrine or dopa‐mine administration all of the ependymal surfaces studied appeared as in control rats. The increase in bleb‐like protrusions noted in the floor of the third ventricle after the injection of epinephrine or dopamine are suggestive of a secretory process rather than a manifestation of an absorptive function in this region.
Endothelial detachment sites in glomerular capillaries of vinblastine‐treated rats
Authors: Tyson Greta E. , Bulger Ruth Ellen 
Published: February 2005

AbstractIn Wistar‐Fürth rats given vinblastine sulfate intravenously, an abnormality of the glomerular capillary wall was observed. Electron micrographs of renal corpuscles of treated animals revealed sites where the glomerular endo‐thelium had separated from the glomerular basement membrane. The resultant subendothelial space contained a flocculent material similar in appearance to the blood plasma present within the capillary lumen. Endothelial detachment sites were observed near the mesangial region, as well as in parts of the capillary loops distant from the mesangium.Vinblastine treatment also resulted in a disappearance of microtubules from the cytoplasm of endothelial cells and in an appearance of paracrystalline inclusions which were similar in fine structure to those reported in previous studies using Vincaalkaloids. Although these intracytoplasmic paracrystals were common in the glomerular endothelium of treated animals, they were rarely seen at sites of endothelial detachment. The way in which vinblastine treatment elicits endothelial detachment is not known.
Histologic and histochemical evidence concerning the presence of morphologically distinct cellular zones within the rabbit atrioventricular node
Authors: Anderson Robert H. 
Published: February 2005

AbstractThe rabbit atrioventricular nodal region has been studied using a method of tissue preparation allowing direct comparison of adjacent sections processed by histological and histochemical techniques. By this means, specialized cardiac tissue is found to occupy the region defined electrophysiologically as the atrioventricular node. This region is more extensive than that previously defined by light microscopy. Within this region three types of cell are distinguishable; transitional cells, and upper and lower nodal cells. The last are continuous with and identical to the cells of the atrioventricular bundle. The cell types also exhibit differences in their pattern of innervation. The significance of these cellular zones and their associated nerves is discussed with reference to previous electrophysiological findings and the mechanism of nodal delay.
Response of hamster thyroid light cells to plasma calcium
Authors: Biddulph David M. , Maibenco Helen Craig 
Published: February 2005

AbstractLight cells in the hamster thyroid gland were examined by electron microscopy and histochemical methods in control, hypercalcemic and hypocalcemic animals. Elevation of plasma calcium levels stimulated a marked depletion of light cell granules as detected by electron microscopy and silver impregnation. In the hypercalcemic state the size and number of light cells did not differ from that of control animals. Hypocalcemic hamsters showed a significant increase in light cell numbers with marked hypertrophy and hyperplasia of this cell type. These observations support the view that the light cell in the hamster thyroid is associated with thyrocalcitonin secretion.
Abnormal sex cord formation and an intratesticular adrenal cortical nodule in a human fetus
Authors: Roosen‐Runge Edward C. , Lund Joanna 
Published: February 2005

AbstractA combination of two developmental abnormalities never described before, a nodule of adrenal cortical tissue and some severely stunted sex cords, in the right testis of a four‐month‐old human fetus are described in detail. In the left testis a few abnormal cords were found but no adrenal tissue was seen. The possible origin of the abnormalities is discussed. It is suggested on circumstantial evidence that the ectopic adrenal cortex migrated into the testis near the end of the period during which the pattern of sex cords becomes established (around day 40 ?) and began exerting an inhibiting influence on the development of the sex cords as soon as endocrine function began, probably somewhat before the end of the third month. This influence probably did not last long.
On the expulsion of the erythroid nucleus and its phagocytosis
Authors: Skutelsky Ehud , Danon David 
Published: February 2005

AbstractElectron microscopical examination of thin sections of guinea pig and rabbit bone marrow indicates that nuclei of their normoblasts undergo constriction during their expulsion.Late erythroblasts in bone marrow of adult rabbits and guinea pigs were often seen surrounded by cytoplasmic protrusions of macrophages. No such contact was observed between macrophages and erythroblasts that were expelling their nuclei in the lumen of blood sinuses of rabbit bone marrow. It is concluded that macrophages are not necessary for nuclear expulsion.
Electromyography of sartorius muscle
Authors: Johnson C. Emory , Basmajian John V. , Dasher William 
Published: February 2005

AbstractThe sartorius muscle of ten normal subjects was studied by elec‐tromyography. It is most active during flexion of the hip and only slightly active during lateral rotation and abduction of the hip. The muscle is usually more active during knee flexion than during extension, but this is not universal. Apparently in some persons it plays a role in knee extension in addition to its knee flexion action, depending on knee position and variations in insertion. Sartorius appears to be a regulator in hip flexion and lateral rotation during the swing phase of gait.
Effect of injected human immunoglobulins on fetal rat development. Spinal, neural and osseous changes
Authors: Kamrin Benjamin B. 
Published: February 2005

AbstractRabbit anti‐rat‐brain serum immunoglobulins injected into pregnant rats on the ninth, tenth, eleventh or twelfth day of gestation resulted in a fetal resorption rate 15 to 30 times higher than that found in normal untreated pregnant rats. Human serum immunoglobulins obtained from normal postpartum mothers produced a similar percentage of fetal resorption when injected by the same routes into pregnant rats of the same gestational age. In neither of the above experiments were malformations detected among the delivered 20‐day fetuses. Injection of human serum immunoglobulins obtained from mothers of children with spina bifida manifesta into pregnant rats along similar routes and periods gave comparable fetal resorption rates. Injection of the above immuno‐globulin into the lumen of the uterus adjacent to implantation sites gave a low fetal resorption rate and produced varying degrees of skeletal and soft tissue malformations among the viable survivors.The only difference which could be discerned between normal postpartum immunoglobulins and those obtained from mothers of spina bifida manifesta children was characterized in the latter by a two‐fold increase in the IgG levels and the immunoelectrophoretic reactivity of its immunoglobulins with human spinal cord antigens. The developmental defects observed were: 1. Cranial‐thinning and bleb formation of skull bones; widening of the foramen magnum; descent of the obex closer to the foramen magnum. 2. Skeletal‐delayed or inhibited calcification of the bodies and spinous processes of the thoracic and lumbar vertebrae; widening of the vertebral canal and central canal of the spinal cord.
The cytoarchitecture of normal mouse lens epithelium
Authors: Rafferty Nancy S. 
Published: February 2005

AbstractThe lens epithelium of 30 gm male albino CF1 mice was characterized by determining the area dimensions and the mitotic rate of the total and of the several different regions of whole‐mount preparations. A ring of nonpigmented iris cells is found to adhere to the outer surface of the lens cuticle, which serves to delineate an inner central zone from an outer peripheral zone of the epithelium. A high number of dividing cells in the peripheral area, especially immediately adjacent to the meridional rows, but including the area overlain by the iridial fringe of cells, identifies this wide region as the proliferative zone. The mitotic rate, furthermore, undergoes marked diurnal variation, rising in the late evening through the early morning hours and diminishing during the late morning and afternoon hours.