bluuebunny/crossref_metadata_2025_split huggingface dataset:
Age changes in the blood supply to molar teeth of rats
Authors: Bernick Sol 
Published: February 2005

Abstract1. Rats, varying in age from one month to over one year, were used to study the changes in the vascular supply to the molar teeth and periodontium as a result of aging. The blood vessels were demonstrated by the saline‐India‐gelatin perfusion method. The jaws and teeth were fixed in a formol‐acetic acid‐alcohol solution, decalcified, dehydrated, and embedded in nitro‐cellulose in the usual manner. The embedded specimens were sectioned at 100–250 μ, cleared by the Spalteholz method and mounted unstained.2. In immature animals (younger than four months) the pulpal terminal vascular capillary networks were located at the predentin border. As the animals became progressively older, there was a gradual “withdrawal” of the terminal capillary plexuses from the odontoblastic zone so that at eight months of age, all the vascular terminals were restricted in location to the pulpal‐odontoblastic border.3. In the young animal the vessels supplying the periodontal ligament passed gingivally paralleling the bony surface of the membrane with the cemental side being devoid of vessels. During the process of aging, the above basic pattern was altered in the following manner: (a) The apposition of cellular cementum on the apical third of the root was accompanied by the presence of capillary terminals in or adjacent to the layer of cellular cementum. (b) There was a progressive decrease and eventually a loss of the interseptal vessels and their perforating branches. (c) Vascular twigs originating from the main periodontal vascular trunk were found in areas of cemental resorption indicating their need in the process of repair.
Vaginal cycles in the rat after x‐ray or other damage to one or both ovaries
Authors: Plagge James C. , Krehbiel Robert H. 
Published: February 2005

AbstractDamage to the rat ovary at 60 days of age causes irregularities in the estrous cycle and leads to continuous cornification of the vagina. These vaginal changes occurred within two to three months after bilateral irradiation (800 or 2,000 r) or after bilateral castration and autotransplantation of a portion of one ovary. Unilateral irradiation or ligation of the ovarian arteries at their junction with the uterine artery produces similar changes within five to seven months. Comparable vaginal changes did not occur in control animals until they reached the age of ten months.
A comparison of autoradiographic and alizarin techniques in the study of bone growth
Authors: Dixon Andrew D. , Hoyte David A. N. 
Published: February 2005

AbstractActively growing rats and rabbits received a single intraperitoneal injection of radioactive calcium (2.5 – 10 μc/100 gm) or alizarin red (50 – 100 mg/kg). Contact autoradiographs and gross, macerated dry alizarin specimens were prepared. In addition some alizarin specimens were sectioned serially, without prior decalcification, and the results of the various techniques were compared to determine if morphologic appearance were in agreement.Many similarities were found in corresponding regions of the radioactive calcium and alizarin preparations which included the tibia, cartilaginous joints of the skull base, the bones of the vault, the olfactory fossa, tympanic bulla and the malar process of the maxilla. In every instance the findings were in agreement, particularly in relation to the pattern of deposition and resorption in the growth of these regions, and the results were confirmed by reference to histologic control material.It was concluded that radioactive calcium and alizarin red are deposited similarly in growing bones, including those of the skull, and the results which can be obtained by the use of the two substances are fully complementary.
A hitherto undocumented variation of the inferior mesenteric artery in man
Authors: Benton Robert S. , Cotter William B. 
Published: February 2005

AbstractThe variation appeared in a cadaver, male, Negro, 71 years old. Estimated stature and weight: 6′1″ and 180 lbs. Stated cause of death: Bronchopneumonia.In place of a single inferior mesenteric trunk, two arteies orginated from the aorta 2.6 cm apart, the inferior one located 3 cm superior to the bifurcation of the aorta. The superior artry was directed superiorly and gave origin to two branches: one to the superior portion of the descending colon and another which supplied the entirety of the transverse colon. The inferior artery also gave rise to two branches: one to the inferior portion of the descending colon and the other to the sigmoid colon and rectum.The superior mesenteric artery gave rise to one major trunk to the colon, which divided into ileocolic and right colic branches only.The marginal artery of the colon was well developed and patent throughout its length.Search of the literature, to date, has revealed no description of this variation. Two references to a variation in which the inferior mesenteric artery gave rise to a branch corresponding to the middle colic artery have been found. There is a paucity of literature regarding variations of the inferior mesenteric artery. Consequently it is uncertain whether this is due to lack of observation, small amount of variation, or both.
Fine structure of bone as seen on fracture and cleavage planes by electron microscopy
Authors: Vose George P. 
Published: February 2005

AbstractSurface replicas were made of fracture surfaces and cleavage planes of specimens of human femoral cortex. Examination by electron microscopy indicated no consistent differences in submicroscopic structure when fractures were produced by compression, tension, torsion or bending. Small apertures, ranging from 200 to 1,500 Å in diameter, permeated the extra‐canalicular bone. Higher magnifications indicated that the majority of apertures were truncated canals which were enclosed by collagen fibrils with axes aligned longitudinally with the direction of the canals. When canaliculi were observed in cross section, fibrils were observed to radiate at right angles from the canalicular axis for approximately 1 μ. No differences in submicroscopic structure were observed between adult bone and that of a 12‐year old child.
Congenital deficiency of the vertebral pedicle
Authors: Wells L. H. 
Published: February 2005

AbstractThree examples of unilateral partial absence of the vertebral pedicle have been described, involving respectively a last lumbar and a first and a second sacral vertebra. The condition in the first sacral vertebra is associated with spina bifida occulta, so that part of the vertebral arch forms an independent bony element. In the lumbar vertebra the deficiency is anterior to the transverse process, but does not involve the costal element; in the sacral vertebrae it is between the transverse and superior articular processes. The superior articular process of the lumbar vertebra on the affected side is deformed so that the direction of its articular surface is reversed.It is suggested that pedicle defects result from degenerative changes in the neural process prior to ossification. Deformities of the articular processes may be related to the occasional presence of a separate center of ossification for the inferior articular process.
Histochemical correlates for differences in functional activity of kidneys from active and cold‐stored summer bats (Myotis lucifugus)
Authors: Melman Arnold , Rosenbaum Robert M. 
Published: February 2005

AbstractFourteen female Myotis lucifugus from a summer colony were adapted to laboratory conditions for periods up to 60 days. Animals were then divided and exposed to the following conditions: (I) active bats exposed to normal summer laboratory temperature and humidity; (II) active bats exposed to normal summer laboratory temperature but low humidity; (III) cold‐stored bats; (IV) cold‐stored bats exposed to low humidity. All cold‐stored bats entered a state of apparent deep hibernation, carrying out characteristic reflexes upon being awakened. Their thyroid glands showed significant loss of secretory activity.Staining for ATPase activity (method of Wachstein and Meisel) on formalin‐fixed sections of kidney showed that there was increased infolding as well as increased enzymic activity of the plasma membranes of the proximal convolutions from all cold‐stored bats. Proximal convolutions from kidneys of active bats showed decreases in the degree of invagination of the plasma membranes with apparently expanding basal lamellae. Acid phosphatase activity (Gomori) was confined to “phagosomes” in the proximal convolutions of active bats; cold‐stored bats showed no activity. Staining with the periodic Schiff method showed irregular staining of the brush border of tubules from active bats; cold‐stored animals showed a regular brush border with this method. The results suggest that the histochemical methods employed reveal differences in kidney function between the active and cold stored animals.
Structural changes in the ovaries of IF mice due to age and various other states: Demonstration of spontaneous pseudopregnancy in grouped virgins
Authors: Mody Jer K. 
Published: February 2005

AbstractThe ovaries of inbred IF mice were studied at ages ranging from 16 to 70 weeks in four experimental groups: virgins grouped in fours, virgins rendered anosmic by removal of the olfactory lobes, females kept with vasectomized males (i.e. pseudopregnant) and post‐breeding females.The ovarian structural changes taking place with age are described, pointing out the differences in findings with other strains of mice. Further, two structures termed “anovular buds” and “dark‐staining epithelial cells” have been distinguished as separate entities arising from invaginations of proliferating germinal epithelium, especially in old ovaries.The ovaries of virgins were similar to those of pseudopregnancy group of mice and showed a large number of corpora lutea. In both groups, uterine endometriosis occurred and the estrous cycles were of a pseudopregnancy type. Further, good lobular development in the mammary glands of the virgins is seen as in the pseudopregnancy group of mice. These similarities furnish evidence for the occurrence of spontaneous pseudopregnancy in grouped IF virgin mice.When spontaneous pseudopregnancy is prevented by removal of the olfactory lobes, the ovaries become precociously senile. The atrophic ovaries, have a loose folded germinal epithelium around the shrunken ovary, contain many atretic follicles and are conspicuously lacking in intact corpora lutea. The uteri are thin and threadlike. The lobular acinar development of the mammary glands is inhibited.
Effect of serial transplantation on the growth of neonatal pancreas in the hamster
Authors: House E. L. , Jacobs M. S. , Pansky B. 
Published: February 2005

AbstractNeonatal pancrease was implanted in the cheek pouches of cortisone‐treated normal and diabetic hamsters. They were permitted to remain in these sites for: 5–6; 13; 15–16; 19–20; 26 and 36 days, at which times small pieces were transferred to the pouches of cortisone‐treated secondary hosts. The size of the growth was measured at intervals in both hosts. After a final measurement, 23–25 day after transplant, the graft in the secondary host was removed and prepared for histological study. Growth in the secondary hosts was compared both with that found in a large group of similarly‐treated hamsters and with the growth of this same material while it grew in the primary host. In general, except for one or two brief time periods, there was either no significant size difference or the growth in the secondary host was significantly less than in primary hosts. Histological studies of transplants from secondary hosts showed very poor pancreatic differentiation. In no case was recognizable islet tissue found in the pouches of secondary hosts.
Spatial variations between certain cranial and cerebral structures and the anterior and posterior commissures of the living human
Authors: Bauserman Steven , Meyers Russell , Fry William J. 
Published: February 2005

AbstractRecorded are the quantitated empirical findings and statistical variations of spatial configurations prevalent among certain cranial and cerebral structures related to the intercommissural line as encountered in 50 stereotactically‐performed, radio‐opaque lateral ventriculograms of the living human. A physicomathematical technique of mensuration was devised to overcome the difficulties that regularly arise when fixed postmortem specimens are employed to study the same relationships. Clearly, the reliability of human stereotactic atlases is a function of the technique of mensuration employed.Mean length of the intercommissural line was 24.50, and Range 20.90 to 30.90 mm. Mean distance from inferiormost aspect of sella turcica to posteriormost aspect of anterior commissure was 28.30, Range 23.80 to 36.60 mm. Mean length of line from “center” of external auditory meatus to anteriormost aspect of posterior commissure was 43.36, Range from 35.2 to 49.3 mm. Mean angle formed by “line” of orbital roof and intercommissural line was 19.78° and Range, 8.50° to 29.50°. Mean angle between Reid's base line and intercommissural line was +0.04°, Range, from −9.90° to +10.20°. Mean angle between line from “center” of external auditory meatus to anteriormost aspect of posterior commissure and Reid's base line was 97.93°, Range 85.40° to 120.45°.The least variable relationships of the six studied were the distances (a) from the external auditory meatus to the posterior commissure and (b) from the floor of the sella turcica to the anterior commissure.
Histochemical studies on the yolk nucleus in the oogenesis of Indian Reptiles
Authors: Guraya Sardul S. 
Published: February 2005

AbstractThe yolk nucleus of the young oocyte of reptiles is situated in the juxta‐nuclear cytoplasm. It is a homogeneous spherical mass and histochemical tests indicate that it is rich in RNA and proteins. It constitutes a center of high synthetic activity. Lipid inclusions of diverse nature and mitochondria appear in abundance in association with the yolk nucleus. Eventually the yolk nucleus disintegrates and its RNA‐containing substance as well as the other inclusions are distributed throughout the cytoplasm. During yolk formation, lipid inclusions and mitochondria are absorbed by the cytoplasm but the yolk nucleus substance continues to persist among the growing yolk bodies which arise de novo from the cytoplasm. This occurs possibly under the activity of RNA‐containing substance of the yolk nucleus, mitochondria and lipid inclusions.
On the ultrastructure of spinal nerve roots in the frog (Rana pipiens)
Authors: Pick Joseph , Gerdin Carin , Delemos Carmen 
Published: February 2005

AbstractAn electron microscopical study was made of the seventh and tenth ventral and dorsal spinal nerve roots and peripheral nerves of adult frogs, to determine whether or not tunicated and sheathed nerve fibers extend into the spinal cord and into the periphery. The nerves were exposed under urethane anesthesia, fixed in 1%, veronal acetate‐buffered osmium tetroxide (pH‐7.6) plus 0.495 gr/10 ml sucrose, and refrigerated over two hours. Thin cross and longitudinal sections were made and examined with a Siemens electron microscope. A few tunicated fibers were found in the peripheral nerve, but not in the spinal nerve roots which consisted of myelinated and unmyelinated (Gasser‐type) axons. Therefore, tunicated and sheathed nerve fibers were restricted to sympathetic ganglia. This was the more likely, because intrinsic neurons are absent in the sympathetic, and nearly all axons are myelinated in caudal rami communicantes. It was further suggested that preganglionic fibers, after entering, and postganglionic fibers before leaving the sympathetic ganglion changed their myelin sheaths, and appeared as tunicated and sheathed fibers. No structural differences between afferent and efferent cholinergic or adrenergic fibers could be detected in spinal roots. Large vesicles with dark centers, probably containing catecholamine, and dense punctate granules, occurring in sympathetic fibers, were virtually absent in spinal root fibers.
Estrogen‐induced changes in the golgi apparatus and lipid of the uterine epithelium of the rat in the normal cycle
Authors: Elftman Herbert 
Published: February 2005

AbstractThe Golgi apparatus of the uterine epithelium of the rat starts to increase in size during the transition from diestrus to proestrus and continues to enlarge until it reaches its maximum development in estrus. Regression takes place during metestrus. The accumulation of phospholipid at the base of the epithelial cell, characteristic of diestrus, decreases in quantity as the Golgi apparatus increases in size and reappears as the Golgi apparatus regresses. Both of these changes are responses to circulating estrogen and form part of the complex series of reactions by means of which this hormone exercises its control over reproductive function.
The intrahepatic and intracellular distribution of copper following chronic administration of the metal in the diet
Authors: McNary William F. 
Published: February 2005

AbstractA histochemical and electron microscopic study of the liver in rats fed a diet containing excess amounts of copper was made to demonstrate the intrahepatic, intralobular and intracellular distribution of the metal.Histochemically copper was demonstrated first at the periphery of the hepatic lobuleand appeared throughout the lobule as the amount of metal increased. Within the hepaticcell copper was demonstrated in the pericanalicular cytoplasm. As the amount of metal in the liver increased occasional perinuclear caps or plaques were formed. Hematoxylin and eosin stained sections of livers with high copper content differed from normal by the presence of light brown pigment. Copper was demonstrated histochemically in the spleen and kidneys of copper fed animals as well as in the liver.Electron microscopic studies of the hepatic cells from copper fed rats revealed numerous irregular dense bodies and pigment granules in the pericanalicular cytoplasm. The dense bodies were enclosed by a single membrane and contained granular material. The appearance of these pericanalicular bodies was associated with loss of histochemical acidphosphatase activity.
Variations in osteoblastic activity with age by the osteoid seam index
Authors: Villanueva Antonio R. , Sedlin Elias D. , Frost Harold M. 
Published: February 2005

AbstractThe need for the replacement of pre‐existing osseous tissue due to various physiologic and pathophysiologic demands is fulfilled by the resorption‐formation processes of the skeleton. These processes can be broadly categorized into two phases: Internal remodelling or the replacement occurring within the periostealendosteal envelope, and growth remodelling or the remodelling occurring at the periosteal‐endosteal surfaces during growth. The authors reason that changes in the numbers of new osteons found in cortex with age would provide insights into the mechanism (s) governing the production of these centers of new bone formation.Undecalcified cross‐sections of human rib from 139 relatively normal subjectsranging from one month to 84 years of age were prepared by Frost's method and stained with 1% basic fuchsin. The total number of osteons containing active osteoidseams was determined. The surface area of each cross‐section was measured and the data converted to a unit of number of seams/mm2 of cortex. The largestnumber of seams/mm2 occurred in infancy, with a gradual decline until the fourth decade. This was followed by a subsequent rise with a secondary peak in the seventh decade. The differences in means of the fourth and seventh decade were significant at the 1% level. Similar changes were noted in specimens of clavicle in 34 of the study cases.It is felt that the data indicates a net suppressive effect by gonadal hormones on the process of internal remodelling of diaphyseal cortex. Since the numbers of seams present at any given instant are representative of previous events affecting differentiation of the mesenchymal cell, the data indicates that the mechanism(s) controlling this process in the internal remodelling of rib and clavicle cortex may be independent of the mechanism(s) controlling differentiation of mesenchymal cells in growth and maturation of the skeleton.
An enzymatic‐histochemical study of the corpus uteri of the mouse
Authors: Thiery Michel , Willighagen Roelof G. J. 
Published: February 2005

AbstractThe authors have investigated in the component parts of the uterine corpus of the C3H/N mouse the distribution pattern of 15 enzymes, some of them for the first time. In the endometrial epithelium alkaline and acid phosphatase, 5‐nucleotidase, adenosinetriphosphatase, β‐glucuronidase, NADD, NADPD, and the dehydrogenases studied, were found to show cyclical variations in intensity and localization which parallel the estrogen impregnation of the animal. Cyclical variations in intensity were found in the endometrial stroma for the activity of alkaline phosphatase, adenosinetriphosphatase, and β‐glucuronidase. Analogous variations in the myometrium are reported for alkaline phosphatase and β‐glucuronidase. A relationship between the functional activity of fibroblasts and the intensity of the activity of alkaline phosphatase is suspected in the subepithelial connective tissue. Macrophages show activity of a variety of enzyme systems. Their high acid phosphatase activity is to be attributed to storage of organic substances deriving from the breakdown of the endometrial epithelium. A similar relationship between enzyme activity and storage function is suspected for β‐glucuronidase. The sudden increase in the aminopeptidase activity in the endometrial epithelium and stroma at the end of the estrous cycle may be the expression of the intense catabolic phenomena which characterize this phase.
Normal and abnormal expansion of the lungs of newborn infants obtained at autopsy III. The pattern of aeration as affected by gestational and postnatal age
Authors: Gruenwald Peter 
Published: February 2005

AbstractLungs of 482 infants were examined by artificial inflation. The pattern of aeration is recognized best when expansion is incomplete. It varies strikingly with maturity: inpreviable fetuses (approximately 1,000 gm or less) and in mature infants (above 2,000 to 2,500 gm) air is distributed at random. In viable premature infants with a birth weight between these two groups, aeration of the bronchi and respiratory bronchioles without expansion of the alveoli (atelectasis of prematurity) is accomplished with relative ease, whereas opening of the alveoli requires much higher pressure. In infants born too small for their gestational age, the pattern of expansionfollows gestational age rather than birth weight. If the normal surface active lining of the air spaces is inactivated or absent, the stability of expansion is reduced and extensive collapse occurs at each expiration. This favors in the lungs of premature infants the recurrence, and eventually persistence of atelectasis of prematurity. Expansion by liquid media shows that the architecture of these atelectatic lungs is normal. The tendency toward atelectasis of prematurity is a function of prematurity, and is independent of the formation of hyaline membranes.