bluuebunny/crossref_metadata_2025_split huggingface dataset:
Neurosecretory material in the supraoptico‐hypophyseal tract of the bat throughout the hibernating and summer periods
Authors: Troyer J. Robert 
Published: February 2005

AbstractNeurosecretory material in the supraoptico‐hypophyseal tract of 151 hibernating and summer bats (Myotis lucifugus lucifugus) was studied in chromealum‐hematoxylin‐phloxine‐stained serial sagittal sections. Seasonal variations of neurosecretory content throughout the hibernating period (mid‐September through mid‐May) and “active” summer period (June to mid‐September) were observed and the staining density of the neurosecretory material in the supraoptic nucleus, infundibular stem and pars nervosa was “quantitated” visually. Cell counts and measurements also were made to determine if cell number and size changes accompanied seasonal changes in neurosecretory content.A significantly greater staining density of neurosecretory material in the supraoptico‐hypophyseal tract of the hibernating bats, than in the “active” animals was observed. These differences were always greater in the infundibular stem than in the supraoptic nucleus and pars nervosa. Although there was no correlation between seasonal activity and the total number of neurosecretory cells in each brain, there was always a smaller number of dark‐staining cells in the “active” bats than in those that were hibernating. Nucleocytoplasmic ratios of hibernating bats were below those of the active animals. These resulted from smaller nuclear and larger cytoplasmic sizes during hibernation than in the summer. Nucleolar sizes, however, were slightly greater in the hibernating bats than in the active animals. The significance of these results in terms of seasonal activity is discussed.
Interference with early pregnancy in rats by estrogen: Mechanism of action of dienestrol
Authors: Harper M. J. K. 
Published: February 2005

AbstractRats were given single doses of an orally‐active estrogen by mouth on days 1–5 of pregnancy. Examination of uteri on day 8 for implantations revealed that the median effective doses for preventing 50% of the eggs shed from implanting were 0.047, 0.050, 0.035, 0.145 and 0.380 mg/kg for days 1, 2, 3, 4 and 5 respectively. It was found that failure of pregnancy after treatment with the minimal 100% effective dose (ED100) on days 1, 2 or 3 was due to expulsion of eggs from the reproductive tract by day 5. Treatment of rats with the ED100 on day 4 caused expulsion of some eggs from the tract by day 5, but also had effects on the uterus: the position of the blastocysts within the lumen was abnormal and their orientation relative to the mesometrial‐anti‐mesometrial axis disturbed. No decidual reaction was observed on day 6 in such rats or on day 9 in pseudopregnant rats treated similarly and subjected to uterine traumatization on day 5. Treatment with ED100 on day 5 had no effect on egg transport or on the positioning of blastocysts within the lumen on day 6. A decidual reaction was seen around the blastocyst on day 6, but in pseudopregnant rats treated similarly and subjected to uterine traumatization on day 5 no decidual reaction was found on day 9. The pontamine blue reaction was negative in nearly all rats dosed on day 4 and examined on days 6–8. In rats dosed on day 5, however, the blue reaction was negative on day 6, but positive on day 7, i.e., delayed by 24 hours compared to controls and appearing later than the decidual reaction. The blastocysts were unattached in these rats on day 6, but may have attached briefly on day 7 (suggested by the positive blue reaction) and subsequently failed to develop further owing to disappearance of the decidual tissue.
Solitary neurons in human tongue
Authors: Chu C. H. U. 
Published: February 2005

AbstractMany solitary neurons, each encapsuled by a number of satellite cells and surrounded by collagenic fibers and unaccompanied by other nerve cells, are observed in specimens of the posterior third of the human tongue. They are ganglion cells of the parasympathetic nervous system supplying postganglionic fibers that are adenomotor to von Ebner's gland and myomotor to the smooth muscle of blood vessels. The occurence of solitary neurons suggests that a “ganglion” may consist of a single nerve cell. It is emphasized that the lingual branch of the glossopharyngeal nerve supplying the posterior third of the human tongue is not a sensory but a mixed nerve.
Observations on the distribution of intrarenal nervous tissue
Authors: Gosling John A. 
Published: February 2005

AbstractThe distribution of intrarenal nervous tissue in a number of species has been examined using a cholinesterase technique. Particular attention has been paid to the relationships between the renal vessels and their nerves. Nerves were detected alongside the major intrinsic renal vessels and formed nerve networks on the external aspects of the arterial tunicae mediae. In all specimens, afferent arterioles were accompanied by nerves the majority of which terminated near the entrance of cortical afferent arterioles into their respective glomeruli; nerves along juxtamedullary afferent arterioles continued across glomerular hila. Relatively few nerves were demonstrated near cortical efferent arterioles while juxtamedullary efferent vessels possessed a rich innervation. Intramural smooth muscle was identified in juxtamedullary efferent arterioles, aglomerular vessels and arteriolae rectae and these vascular segments were accompanied by nervous tissue. Cholinesterase positive nerves could not be detected in the renal medulla.
Electron microscopic studies on granulocytopoiesis in the slender salamander
Authors: Campbell Ferrell R. 
Published: February 2005

AbstractThe morphology of differentiating heterophils and eosinophils of the slender salamander, Batrachoseps attenuatus, was studied with electron microscopy. Enzymes of the granules of both cell types appear to arise from the Golgi cisternae. An agranular stem cell was not observed and the least differentiated cell type encountered was an “early” promyelocyte having small granules which are morphologically distinct from mature granules of either the heterophil or eosinophil series. Heterophil myelocytes and later stages contain only one population of granule which is fibrous in content. Eosinophils likewise possess but one type of granule; the granules are larger than those of heterophils, have a homogeneous content, and lack the crystallin core so characteristic of mammalian eosinophils.
A quantitative study of the blood vessels of the pig's skin and the influence of environmental temperature
Authors: Ingram D. L. , Weaver M. E. 
Published: February 2005

AbstractThe vascular supply to the skin of pigs was studied in animals perfused with the dye, monastral fast blue. The arrangement of the blood vessels in control animals was in three plexuses, similar to that in other mammals but with the middle plexus poorly developed.A litter of pigs was divided into two groups at the age of 12 days and one group was raised in a warm room and the other in a cold room. The pigs were killed at age three months when the warm room was 35°C and the cold room 5°C. A quantitative evaluation of the blood supply to the skin of the experimental animals revealed that the pigs from the warm room had more blood vessels in the skin than those raised in the cold; the difference was statistically significant (P < 0.01). In the case of pigs from a second litter reared at 35°C and 20°C, no significant difference in the number of blood vessels was detected.
The evolution and development of the dens of the mammalian axis
Authors: Jenkins Farish A. 
Published: February 2005

AbstractCertain members of the extinct reptilian group from which mammals evolved possessed both a dens and an atlas body. Available paleontologic evidence supports the conclusion that the dens evolved as an addition to the atlas body. There‐fore, the dens is not homologous with the atlas body as is generally claimed on the basis of supposed developmental evidence. The atlas body is large in the most primitive of living mammals, the monotremes, which also possess a dens of typical mammalian proportions. In metatherian and most eutherian mammals, both a dens and an atlas body remnant of variable size are present. The development of the dens in the Virginia opossum, Didelphis marsupialis, confirms the fact that the dens arises from, but does not replace, the atlas body anlage. The dens evolved as a functional replacement of the atlanto‐axial articular processes which were lost when the mammalian atlanto‐axial joint became specialized for rotational movement.
Photophores of Porichthys notatus: Ultrastructure of innervation
Authors: Strum Judy May 
Published: February 2005

AbstractPhotophores in Porichthys notatus are bioluminescent organs composed of a lens, photogenic tissue, and an underlying reflector. Nerves penetrate through the reflector and branch, free of their Schwann cells, among the photogenic tissue elements. The tortuous pathways of axons have been followed by electron microscopical serial sections. After giving off occasional terminal branches, the axons continue into pockets of connective tissue which penetrate among the photogenic, supportive, and lens cells. There they form tuft‐like clusters of nerve endings, some of which contain dense‐cored vesicles. None of these endings was seen to penetrate the basal lamina and make direct intercellular contact with either a supportive cell or a photogenic cell. From these observations, it is concluded that the nerves end outside of the basal lamina surrounding photogenic, supportive, and lens cells. Adhesion sites, which may indicate chemical synaptic contact, were occasionally observed among these neural components.The photophores of the California Porichthys notatus often bioluminesce following intraperitoneal injection of the fish with epinephrine. It therefore appears from experimental, anatomical and fine structural evidence, that these luminescent organs are innervated and controlled by the sympathetic nervous system.
The distribution of valves in rat kidney arteries
Authors: Taggart Nancy E. , Rapp John P. 
Published: February 2005

AbstractSerial sections of rat kidneys were studied for the presence of valves. Intimal valves were found in interlobular arteries at sites where arteriolar branches went directly to juxtamedullary glomeruli. Arteriolar branches to glomeruli which are not juxtamedullary glomeruli did not possess valves at their origins. This location suggests that these valves may be important as regulators of blood flow to the vasa recta spuria which supply the medulla.
Ovarian morphological and functional changes in reproductively senescent hamsters
Authors: Thorneycroft Ian H. , Soderwall A. L. 
Published: February 2005

AbstractOvaries from young and senescent hamsters were examined morphologically on days 8, 12 and 14 of pregnancy to determine if there were any differences between the two age groups. The senescent hamsters had fewer follicles present than the young on all days of gestation. The senescent females' corpora lutea experienced the greatest growth between days 8 to 12, whereas corpora lutea from young animals grew the most between days 12 and 14. Corpora lutea in senescent females did not grow at all between days 12 and 14. The lower number of follicles in senescent females was not due to the lower rate of implantation. Superovulation with PMS revealed that the senescent ovary was refractory.It was concluded that there are quantitative not qualitative differences between ovaries from young and senescent hamsters during pregnancy. The refractory ovary of senescent females could be contributing to pregnancy wastage in this species by secreting less progesterone.
A record of “testis cords” in the ovary of a mature hippopotamus (hippopotamus amphibius, Linn.)
Authors: Clough G. 
Published: February 2005

AbstractA small patch of immature‐testis‐like tubules is described from the ovary of a sexually mature, fertile hippopotamus. It is compared with similar tubules described in the literature from other species and it is concluded that the tubules are derived either from cords formed in the foetal ovary or are an early granulosa‐cell tumor.
Aortic cartilage in the heart of Syrian hamsters
Authors: Kelsall Margaret A. , Visci Marguerite 
Published: February 2005

AbstractA C‐shaped bar of hyalin cartilage was present in the fibrous tissue around the aortic orifice in the heart of all 70 male and 10 female Syrian hamsters, 103 to 843 days old. This cartilage has the same cellular and intercellular characteristics as the tracheal cartilages. Fibers from four of the six lunulae of the semilunar aortic valves, the aortic sinuses and vestibule, and cardiac muscle adjacent to the posterior semilunar valve insert onto the fibrous capsule and the protuberances of the aortic cartilage. A few fibers from the ventricular and interatrial septa and the aortic cusp of the mitral valves are also attached to the fibrous capsule. Cartilage did not occur around the pulmonary orifice or in other regions of the heart with the exception of a chondroma in the aortic valve. The C‐shaped aortic cartilage in this hibernating species is discussed in relation to its possible significance in preventing collapse of the aortic orifice and the possibility of increasing coronary blood flow.
The fine structure of the placental villi of the rhesus monkey(Macaca mulatta)
Authors: Luckett W. Patrick 
Published: February 2005

AbstractPlacental villi were obtained from monkeys at the Wisconsin Primate Research Center during 50–150 days gestation. As in the human, the villi consist of a vascular mesenchymal core surrounded by inner cytotrophoblastic and outer syncytiotrophoblastic layers.The syncytiotrophoblast contains abundant rough endoplasmic reticulum and a well developed Golgi complex consisting of stacked lamellae and diffuse vesicles. An asymmetrical distribution of ribosomes occurs on RER cisternae associated with mitochondria. Branched microvilli frequently bear dilated tips and resemble stereocilia. Cytoplasmic tufts and microvilli increase the surface area, and the base of the tuft usually contains a large membrane‐bound vacuole with a flocculent inclusion of low electron density. These vacuoles are lacking after 100 days. In later stages the syncytiotrophoblast bears irregular microvillous processes and specialized attachment sites at its contact with the basal lamina.Hofbauer cells in the villus core contain numerous large vacuoles, coated pinocytotic vesicles and smooth vesicles apparently derived from ER; the latter are sometimes fused to the large vacuoles. Hofbauer cells appear to be derived from undifferentiated mesenchymal cells.
The relationship of cartilage canals to the initial osteogenesis of secondary centers of ossification
Authors: Wilsman Norman J. , Van Sickle David C. 
Published: February 2005

AbstractInitial osteogenesis of secondary centers of ossification in the humeral head of the dog was studied with serial sections, histochemistry, radiography and vascular injections. At birth this chondroepiphysis was found to be well vascularized by a network of cartilage canals. On the second day after birth the first morphological evidence of the secondary center of ossification was seen. This was in the form of multiple foci of calcification. Each focus of calcification occurred immediately adjacent to the glomerular end of a cartilage canal and not in an avascular matrix. The capillaries of the glomerulus were modified in the process and persisted as the blood supply to the secondary center of ossification. By four days of age the individual foci had coalesced into a single larger focus of calcification. This process of ossification was found to possess morphological similarities to that occurring at the metaphyseal side of the epiphyseal plate.
Pulmonary veins in the chick embryo: Origin as determined by radioautographic mapping
Authors: Rosenquist Glenn C. 
Published: February 2005

AbstractIn the head process to early head fold stage chick embryo, the cells which will form the pulmonary veins are located in the mesoderm near the posteromedial edges of the heart‐forming regions. At the 26 somite to early limb bud stage, the presumptive pulmonary vein cells have been folded to the midline of the embryo as part of the splanchnic mesoderm and form the endothelial plexus which courses through the dorsal mesentery of the sinoatrial region of the heart.
Spermatogonial stem‐cell renewal in the mouse
Authors: Oakberg E. F. 
Published: February 2005

AbstractType A spermatogonia in the mouse can be separated into five successive classes on the basis of nuclear morphology and stage of the cycle in which they occur. Enumeration of all types throughout the cycle of the seminiferous epithelium reveals that the As spermatogonia are the stem cells. They divide throughout the cycle and, especially at stages IX to I, form chains of cells which then give rise to spermatogonia A1 at stages II–VIII. The A1 cells divide in IX to form the A2, which divide in XI to form A3, and the A3 cells divide in I to form the class A4 spermatogonia. Spermatogonia A4 give rise only to the In type; there is no evidence for the formation of either As or A1 from A4 spermatogonia. Repeated injections of 3H‐thymidine and tracing the history of labeled cells to 15 days after labeling supported the conclusion obtained from morphological and numerical data that As spermatogonia are the stem cells of the testis.
Popliteus muscle in man
Authors: Lovejoy John F. , Harden Thomas P. 
Published: February 2005

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 fibula.
The relationship between the pubo‐urethral ligaments and the urogenital diaphragm in the human female
Authors: Milley Paul S. , Nichols David H. 
Published: February 2005

AbstractThe connective tissue supports of the human female urethra have been investigated in 14 cadavers and 20 fetuses. In all cases the urethra was found to be suspended from the pubic bone by bilaterally symmetrical anterior, posterior and intermediate pubo‐urethral ligaments. The anterior and posterior ligaments were formed by reflections of the inferior and superior fascial layers of the urogenital diaphragm. The intermediate ligament represented a fusion of these fascial layers and no transverse perineal ligament was found.It is suggested that the term pubovesical ligament is a misnomer since this band of connective tissue passes from the pubic bone to the urethra and not to the bladder. It is thus analogous to the puboprostatic ligament of the male. An anatomical defect in the pubo‐urethral ligaments might be a contributing factor to urinary stress incontinence in the female.
Vascular morphology in hypertensive states in the rat
Authors: Friedman Sydney M. , Scott Gordon H. , Nakashima Miyoshi 
Published: February 2005

AbstractThe morphological characteristics of the tail artery and of the superficial epigastric neurovascular bundle, fast‐frozen in vivo with a cryosurgical probe in less than one second, were examined in norepinephrine and in deoxycorticosterone acetate (DOCA)‐induced systemic hypertension. Acute vasoconstriction produced by norepinephrine begins in the innermost muscle layers and extends by degrees to the outer layers. The pull of the inner cells is distributed through the wall by a network of radially disposed collagen fibers. No qualitative signs of vasoconstriction were observed either in arteries or arterioles in advanced DOCA hypertension. Here, the pattern was dominated by hypertrophy, apparent in the size of the smooth muscle cells and of their nuclei and in a considerable accentuation of cell boundaries indicating an increase in the paracellular matrix.
Electron microscopy of granule release in metrial gland cells of the pregnant rat
Authors: Larkin Lynn H. 
Published: February 2005

AbstractThe fate of the granulated metrial cell was studied with the electron microscope. In the degenerating areas of the metrial gland the granulated metrial cells undergo necrosis. The granules of the lysed cells are enclosed by a limiting membrane and their contents appear unaltered. The observations indicate that after the granules are free, the limiting membrane is lost and the contents released into the tissue space. Phagocytic cells are apparently involved in clearing the area of cellular debris. Metrial granules are sometimes engulfed by the phagocytic cells. The “lipid bearing” cells of the metrial gland were also investigated with the electron microscope. These cells contained few organelles, a flocculent cytoplasmic ground substance, lipid droplets, and large dense bodies. The membrane limited dense bodies resemble secondary lysosomes and contain multilaminated myelin whorls plus a variety of dense fibrous or homogeneous material. The release of metrial granules is discussed in relation to the possible secretion of relaxin by metrial cells. The role of the lipid bearing cells is also considered.
Volumetric composition of the monkey skeleton
Authors: Gong Joseph K. 
Published: February 2005

AbstractFive adult monkeys (Macaca mulatta) having an average weight of 3.4 kg were analyzed for the overall skeletal contents of water, fat, nonfatty organic fraction, volatile inorganic fraction and ash. Volumes of bone and marrow for each skeletal region were calculated according to an earlier method used in the study of the dog and rabbit (Gong and Arnold, '65; Gong and Reis, 1970). A shortcut method for calculating marrow volume and fresh volumes of trabecu‐lar and cortical bone using only two variables, the ash volume (or mass) and the fresh volume of the skeletal region, was also shown. It was found that the marrow constituted approximately 50.7% of the overall skeletal volume. Comparison of the composition of the marrow in the long bone and flat bone regions of the skeleton showed that the general distribution of the various components in these regions was similar to those found in the dog and rabbit; namely, a relatively high fat content in the long bone marrow and relatively high nonfatty organic and water contents in the flat bone marrow.
Muscle spindle distribution in snout musculature of the Japanese shrew‐mole
Authors: Kubota Kinziro , Masegi Toshiaki 
Published: February 2005

AbstractThis investigation was designed to provide the structural basis for snout‐mandibular movement of insectivores. Muscle spindle distribution in the snout musculature of six Japanese shrew‐moles was examined in serial cross sections stained with hematoxylin‐eosin and azan.Zygomaticus major, Levator labii superioris and Zygomaticus minor contain about 120 muscle spindles but Levator alae nasi superioris and inferioris have no spindles. The spindles are concentrated within the lower half of the musculature. The average of the spindle area of one muscle measured was about 0.1 mm2 and the extent the spindles were observed was 11 mm. The ratio of the spindle area to the muscle area was a maximum of 25% in the posterior one‐third of the belly, 10% in the middle and 1% in the anterior.Since the facial muscles are considered either to be devoid of spindles or few in number, it is of considerable interest that the snout musculature is supplied by abundant muscle spindles. It also suggests that the delicate movements of the snout muscle might be under minute control of the proprioceptive mechanism.