bluuebunny/crossref_metadata_2025_split huggingface dataset:
Testicular characteristics of goldfish Carassius auratus, in nature and under diet limitations
Authors: Clemens Howard P. , Reed Carl A. 
Published: February 2005

AbstractGoldfish testes were nutritionally regressed in about 115 days regardless of season and without controlled light or temperature. A gonosomatic index (testes weight ″ 100/body weight) of the regressed fish was about one tenth that of spawning fish. The regressed testes were primarily composed of spermatogonia, spermatocytes, and connective tissue. Fish testes were maintained in a regressed state for over 200 days with no change in gonosomatic index. Fish with regressed testes appeared to be in a state of “pseudohypophysectomy” with respect to gonadotropin. Pituitary replacement and a diet of 5% of the body weight per day initiated spermatogenesis and brought the regressed testes to functional maturity in one month. The results suggest that spermatogonial proliferation and the maturation of sperm have different regulatory requirements.
Ingestion of particulate matter by the outer surface cells of the mollusc mantle
Authors: Nakahara Hiroshi , Bevelander Gerrit 
Published: February 2005

AbstractA study of the ingestion of particulate matter from the pallial space located between the shell and the outer surface of the mantle of Isognomon alatus and Pinctada radiata was undertaken with the aid of the electron microscope. For this purpose colloidal thorium dioxide (thorotrast) was introduced into the pallial space for periods of 1–5 days after which time the mantle was excised and prepared for examination with the electron microscope. After 24 hours thorotrast micelles were observed in the pallial space, on the surface of the microvilli, in small pinocytotic vesicles between the bases of the microvilli, in vacuoles undergoing coalescence and finally in large dense bodies (lysosomes). Amoebocytes in the pallial space also participate in the removal of particulate matter in a manner similar to that described for the surface epithelium. During active ingestion the Golgi apparatus changes from a vesicular to a lamellar form. The method of ingestion observed in the surface epithelia and the amoebocytes is similar to the ingestion of protein and other particulate material reported for a variety of vertebrate tissues.
Functional morphology and evolution of tail autotomy in salamanders
Authors: Wake David B. , Dresner Ian G. 
Published: February 2005

AbstractBasal tail constriction occurs in about two‐thirds of the species of plethodontid salamanders. The constriction, which marks the site of tail autotomy, is a result of a reduction in length and diameter of the first caudal segment. Gross and microscopic anatomical studies reveal that many structural specializations are associated with basal constriction, and these are considered in detail. Areas of weakness in the skin at the posterior end of the first caudal segment, at the attachment of the musculature to the intermyotomal septum at the anterior end of the same segment, and between the last caudosacral and first caudal vertebrae precisely define the route of tail breakage. During autotomy the entire tail is shed, and a cylinder of skin one segment long closes over the wound at the end of the body.It is suggested that specializations described in this paper have evolved independently in three different groups of salamanders.Experiments and field observations reveal that, contrary to expectations, frequency of tail breakage is less in species with apparent provisions for tail autotomy than in less specialized species. The tail is a very important, highly functional organ in salamanders and it is suggested that selection has been for behavioral and structural adaptations for control of tail loss, rather than for tail loss per se.
Innervation of the respiratory muscles of Gallus domesticus
Authors: Dewet P. D. , Fedde M. R. , Kitchell R. L. 
Published: February 2005

AbstractA detailed gross anatomical study of the innervation of the respiratory muscles was made on twenty mature, male, Single Comb White Leghorn chickens. The aim was to demonstrate the general pattern and degree of terminal branching of the intercostal and lumbar nerves that innervate respiratory muscles.The point of entry for all nerves was on the medial face of the proximal third of the belly of the muscles, except for the transversus abdominis and costopulmonary muscles. The nerves were not always accompanied by blood vessels at the point of entry but both were invariably related at their terminal branches within the muscle belly and the tendon or aponeurosis. Within the muscle, primary, secondary, tertiary, and quarternary subdivisions of nerves coursed parallel to the muscle fibers, but some were tortuous. Plexus formation and/or segmental nerve anastomosis was most evident in strongly active expiratory and inspiratory muscles, i.e., all abdominal muscles and the m. costisternalis pars major.A craniocaudal gradient in the size and development of the contractile mass of the intercostal muscles was observed. The mm. intercostales interni increased in size in the caudal intercostal spaces, while the reverse was true for the mm. intercostales externi. Variable forms and sizes of lateroventral abdominal muscles were observed and the m. rectus abdominis was consistently present.The mm. intercostales interni and externi received branches from both the nn. intercostales interni and externi.
Hypothalamic neurosecretion in relation to water deprivation in ploceids of arid and swampy zones
Authors: Kripalani Kamla , Ghosh Asok , Rahman Hamidur 
Published: February 2005

AbstractThe effects of 72 hours of dehydration on the hypothalamo‐neuro‐hypophyseal system have been compared in three avian species which originate from different climatic habitats but belong to the same genus, Lonchura. In L. malacca, which is an inhabitant of swampy, non‐arid regions, the neurosecretory nuclei are activated and there is a depletion of neurosecretory material from the nuclear regions and neurosecretory tract, as well as from the neurohypophysis. In L. punctulata, an inhabitant of woods and grasslands, the supraoptic cells show signs of activation. To some extent, a depletion of the neurosecretory material is observed from the neurohypophysis. In the fibrous layer the continuity of the neurosecretory material along the tract is not maintained to such an extent as in the control. In L. malabrica, which lives in semi‐arid regions, there is some activation of the supraoptic nuclei but there is little to no depletion of the aldehyde fuchsin‐positive material from the neurohypophysis and the tract leading to it. The results of this investigation are indicative of a correlation between the neurosecretory mechanism and ecologic adaptation.
Cytoplasmic filaments and associated lucké viruses in the frog renal adenocarcinoma
Authors: Lunger Philip D. 
Published: February 2005

AbstractThe morphology and possible functional significance of cytoplasmic filaments associated with herpes‐like viruses of the frog renal carcinoma is described. Filaments, invariability arranged in elongated bundles or sheaths, individually measure approximately 30 mμ in diameter, and are composed of finely granular, proteinaceous material. During the viral maturation sequence, this material is believed to be deposited on the surface of the capsid, thereby possibly providing the virus with a defensive coating prior to ergression from the cell.
The development of the insect nervous system. I. An analysis of postembryonic growth in the terminal ganglion of Acheta domesticus
Authors: Gymer Anne , Edwards John S. 
Published: February 2005

AbstractThis study describes the post‐embryonic growth of the terminal ganglion in Acheta domesticus in terms of volume and cell number. All measurements were made at the beginning of each instar from hatching until the final moult on animals reared under controlled conditions. The terminal ganglion increases about 40‐fold in volume from 2 × 106 μ3 in the first instar to 85 × 106 μ3 in the adult. A double logarithmic plot of ganglion volume against body weight shows that the ganglion volume is a function of body weight to the 0.56 power. Initially the neuropile grows at a greater rate than the cortex; in later stages they increase at the same rate.Increase in cell number was determined from serial sections. The total number of cells, based on corrected nuclear counts, increases from 3,400 to 20,000. There is little or no increase in the number of neurons. There are approximately 2,000 association neurons and 100 motor neurons in all stages. The number of glial cells increase from 1,000 to 17,000. Their multiplication rate appears to be related to the increase in neuron volume.Despite the increase in glial cell number, increase in cell volume is primarily responsible for the increase in total volume of the ganglion.
Functional anatomy of the heart of the fruit‐eating bat, Eidolon helvum, Kerr
Authors: Rowlatt Ursula 
Published: February 2005

AbstractSeventy‐seven hearts from one species of bat, Eidolon helvum Kerr, have been examined as a preliminary step in correlating cardiac form the and function in relation to flight in mammals. The supposition is that the heart, like the upper limbs and pectoral girdle, will show deviations from the common mammalian plan because of the animal's unusual way of life.The first thing that happens in flight, as in any form of exercise, is an immense increase in venous return to the heart. The architecture of the sinus venarum of the right atrium and of the right ventricle in the region of the atrioventricular valve, including the position of the papillary muscles, may be related to prevention of rapid overdistension of the right side of the heart. The walls of the inflow and outflow tracts of the right ventricle are exceptionally smooth, an anatomical feature that may have significance in that friction may be reduced. The left side of the heart resembles that of other mammals more closely.
The fine structure of tissues in the amputated‐regenerating limb of the adult newt, Diemictylus viridescens
Authors: Norman Wesley P. , Schmidt Anthony J. 
Published: February 2005

AbstractWe have examined the fine structure of injured, repairing and regenerating tissues of the amputated forelimbs of the adult newt: observations were made on wound epithelium, nerves, striated muscle, the regeneration blastema, connective tissues and cartilage.The wound epithelium shows little modulation from the adjacent epidermis: a subjacent glycocalyx and hemidesmosomes are initially absent. Some cells reveal phagocytic activity. As regeneration progresses, a glycocalyx, hemidesmosomes, and an adepidermal reticulum of fibers develop.Nerve fiber degeneration and regeneration lie side by side in the same nerve bundle. Myelin degeneration is evident within 24 hours; neural connective tissues loosen and fibers appear to spread apart.Striated muscle fibers display a nonuniform response to trauma, due to unequal degree of injury inflicted by amputation. The moderately and greatly injured fibers lose their distal fibril organization. There is a numerical increase in mitochondria, and occasionally a pyknotic nucleus is present. The myofiber glycocalyx appears to resist destruction, even when cell degeneration is extensive. Satellite cells have been observed intimately in contact with injured myofibers. Myogenesis is accompanied by an increase in collagen fibrillogenesis associated with adjacent fibroblasts. Many of these latter cells appear to contain intracellular fibrils: the significance of these observations are discussed, and a basis for intracellular fibrillogenesis and tropocollagen accretion is proposed.The fine structure of the regeneration blastema cell agrees with the description offered by others for the adult newt limb regeneration.Early prochondral condensation of blastema cells is described briefly.
Experimentally induced variations in vitelline artery development and circulatory pattern in the early chick embryo
Authors: Levenson Gordon E. , Nelsen Olin E. 
Published: February 2005

AbstractWhite Leghorn eggs were incubated to desired prevasular stages. Each embryo, upon its intact yolk and surrounded by albumen, was rolled from the shell into a sterile 50 ml beaker. In an uppermost position, the blastoderm was lightly stained with neutral red. Three types of localized cuts were made as indicated below, and the beaker‐embryo unit placed in a sterile humidified chamber for further incubation. Results: (1) Unilateral cuts adjacent to the body and parallel with its axis blocked or suppressed formation of the vitelline artery on the cut side, even though healing occurred; (2) A specific site was found in the area pellucida opposite the sinus rhomboidalis which, when lightly cut perpendicular to the body axis, resulted in blockage or shifting of the final junction between aorta and vitelline artery as far cephalad as the thirteenth somite level. Formation of a dual final junction with the aorta also occurred. (3)Transverse cuts through the body axis and into the area pellucida bilaterally, frequently resulted in bilateral blockage or bilateral shifting. In still other cases, growth of a functional loop around the cut to connect the aortae in anterior and posterior segments with the vitelline artery were observed. Other unique circulatory patterns are described.Apparently, slight interference with the capillary plexus which precedes the vitelline artery causes anomalous development. Circulation is considered a major factor in arterial differentiation. Cutting probably alters the plexus and relation of its components to the onset of blood flow.
The post‐embryonic changes in Melipona quadrifasciata anthidioides lep. (hym. apoidea) II. Development of the salivary glands system
Authors: Cruz‐Landim Carminda Da , Mello Maria Luiza Silveira 
Published: February 2005

AbstractThe paper deals with the development of the salivary gland system in Melipona quadrifasciata anthidioides, which begins in the prepupal stage. The silk glands degenerate by autolysis at the end of the larval stage. Degeneration is characterized by cytoplasmic vacuolization and pycnosis of the nuclei of the secretory cells. The glandular secretory portion of degenerated silk glands separates from the excretory ducts. The salivary glands develop from the duct of the larval silk glands. The thoracic salivary glands develop from the ducts of the secretory tubules and the head salivary glands from the terminal excretory duct. The mandibular glands appear in the prepupa as invaginations of mandibular segments, and their differentiation to attain the adult configuration occurs during pupation. The hypopharyngeal glands have their origin from evaginations of the ventral anterior portion of the pharynx. A long tubule first appears with walls formed by more than one cellular layer. Then some cells separate from the lumen of the duct, staying attached to it by a cuticular channel in part intracellular. The initial duct constitutes the axial duct, in which the channel of the secretory cells opens. During the development of salivary and mandibular glands, they recapitulate primitive stages of the phylogeny of the bees. During the development of salivary glands system, mitosis accounts for only part of the growth. Most of the growth occurs by increase in size of cells rather than by cell division. In brown‐eyed and pigmented pupae six days before emergence, the salivary gland system is completely developed, although not yet functioning.
Aspects of the fine structure of the intrahepatic bile duct epithelium in normal and cholecystectomized mice
Authors: Yamada Kazuyori 
Published: February 2005

AbstractThe epithelium lining the intrahepatic bile ducts of normal adult mice consists of a single layer of cuboidal or low columnar cells and has ultrastructure comparable to that described previously (Rouiller and Jézéquel, '65). Some of the epithelial cells, however, exhibit such particular features as dilatation of granular endoplasmic reticulum cisternae, polysome formation of ribosomes and the presence of active forms of the Golgi apparatus, numerous lysosome‐like bodies and apical projections and blebs. Postnatal cholecystectomy does not induce any qualitative changes in the epithelial fine structure, but results in a significant increase in number of the particular structures mentioned. Therefore, the cholecystectomy is thought to stimulate the secretory activity of the epithelial cells, and such stimulation appears due to the absence of a possible activity of epithelial secretion in the gallbladder.
The pituitary in polypterines and its relationship to other fish pituitaries
Authors: Kerr T. 
Published: February 2005

AbstractThe structure and cell types of the closely similar glands of Calamoichthys and Polypterus are described and a general comparison made with the teleost pituitary. The Polypterine gland shows some unsual features in the anatomical disposition of its parts and in the arrangement of its neurosecetory and vascular supply and an explanation of these differences is suggested, based on relative growth changes in later development, in order to include these glands in the evolutionary pattern of the actinopterygian pituitary.
The fine structure of wound repair in an insect (Rhodnius prolixus)
Authors: Lai‐Fook Joan 
Published: February 2005

AbstractThe cells surrounding a wound in the integument of Rhodnius adults show an increase in RNA content, cytochrome oxidase and esterase activity. An excision in the integument is filled by blood which coagulates and is tanned into an insoluble membrane. The basement membrane of the adjoining epidermis acts as a self‐sealing membrane and contracts to cover the excision. The epidermis is attached to the cuticle by the subcuticular layer which it resorbs and by pore canal filaments which are left behind as it migrates. The epidermis migrates as a sheet in contact with the cuticle then with the coagulated blood and basement membrane which cover the excision. Blood cells migrate individually into an excision and do not adhere to a surface in the process. Microtubules cannot be identified with movement. Both epidermal and blood cells remove the cells killed by wounding as evidenced by the appearance of coated vesicles and phagocytic bodies in both cell types. The reconstituted integument consists of a surface membrane in which the layers of the epicuticle are not distinguishable, a nonlamellate cuticle secreted by an epidermis which also appears to secrete the new basement membrane.
Myocardial ultrastructure and electrocardiograms of the sloth (Bradypus tridactylus) under normal and experimental conditions
Authors: DiDio Liberato J. A. 
Published: February 2005

AbstractAdult sloths (Bradypus tridactylus) were studied by electrocardiography and by light and electron microscopy under normal conditions and under experimental conditions as provided for by injection of 2,4‐dinitrophenol (DNP) and ether anesthesia. ECG's of the animals indicated heart rates of 45–71/min, which can be considered as the normal heart rate of the sloth under laboratory conditions. Under normal conditions, the contracted ventricular myocardium of the sloth exhibited (a) a wrinkled sarcolemma, (b) the usual pattern of myofibrils and of sarcoplasmic reticulum, (c) small mitochondria with spiked and branched, often anastomosed cristae, including a few small intramitochondrial dark bodies, (d) an amount of sacrcosomes smaller than the amount of myofibrils, (e) many glycogen granules, isolated, in the form of a chain, or as clusters, in subsarcolemmal, intermyofilamentous and perimitochondrial positions, (f) few multivesicular bodies and (g) large flat sections of the transverse tubular system.Injection of DNP (1 mg/kg) caused tachycardia. With ether anesthesia, the ECG showed monophasic action potential of myocardial injury and prolongation of inter or intraventricular condition. Electrically, the sloth's heart responded to hypoxia as do other mammalian hearts.The administration of DNP produced (a) derangement and reduction in number and length of the mitochondrial cristae, (b) disappearance of spikes, connections between the cristae and, consequently, the honeycombed arrangement, (c) increased matricial space in the center of mitochondria which was often filled with a grayish substance, (d) disappearance of small dark intramitochondrial granules, (e) depletion of glycogen particles and (f) few dilations in the sarcoplasmic reticulum.
Maternal effects on some biochemical characteristics of the blastocyst in the domestic rabbit
Authors: Hafez E. S. E. , Sugawara S. 
Published: February 2005

AbstractBlastocysts from nulliparous, multiparous, superovulated, post‐partum, and lactating rabbits were recovered five to nine days post‐coitum (p. c.), weighed, and dissected in order to obtain the blastocoelic fluid for analysis of glucose, lactic acid, and nitrogen. The largest daily percentage of increase in the volume of blastocoelic fluid occurred between five to six days p. c., whereas, the largest absolute increase occurred between seven and eight days p. c. The weight of the blastocyst and trophoblast, and the volume of fluid was higher in the multiparous and post‐partum does than in others. At eight days p. c., the concentration of glucose in the blastocoelic fluid reached a maximum comparable to the maternal blood level; subsequently a decline occurred. Lactic acid levels were similar to those of glucose. The amount of protein increased dramatically until seven days p. c. The amount of non‐protein‐N to total‐N reached a peak at six days p. c., then declined. The chemical composition of blastocoelic fluid was influenced by the maternal condition, i. e., glucose and lactic acid were higher in superovulated (good response), overcrowded and multiparous groups than in others. While protein was lower in the overcrowded, post‐partum and superovulated groups, it was higher in others.
A new approach to mammalian cranial analysis, illustrated by examples of prosimian primates
Authors: Radinsky Leonard B. 
Published: February 2005

AbstractLatex endocranial casts, which may be made without damaging the skull, reveal much of the information provided by a hemisected skull. Examination of drawings of endocasts superimposed on skulls may provide insight into the biological significance of skull and brain morphology. The high degree of cranial flexion and the globose brain shape of Daubentonia appear to be related to the functional demands of its gnawing mechanism. The broad frontal lobes of indriids are correlated with orbital orientation; differences in frontal lobe sulcal pattern suggest greater elaboration of the motor filed for the hand in indriids than in lemurids. Several features of lorisid cranial anatomy are discussed. It is suggested that, as a first approximation, increased splanchnocranial declination in small prosimians results from the necessity of accommodating relatively large eyes in a skull with a relatively small splanchnocranium.
Quantitative studies of superior cervical sympathetic ganglia in a variety of primates including man. II. Neuronal packing density
Authors: Ebbesson Sven O. E. 
Published: February 2005

AbstractThe volumes of a sample of primate superior cervical sympathetic ganglia were measured and related to body weight and to the number of ganglionic neurons. Estimates of volumes of the ganglia varied between 1.956 mm3 in squirrel monkey and 173.530 mm3 in a human specimen. Average cell densities for the ganglia ranged from 4,455 cells/mm3 in a human ganglion to 32,528 cells/mm3 in a squirrel monkey ganglion. Mean cell territories varied from 0.0000307 mm3 in a squirrel monkey ganglion to 0.0002245 mm3 in a human ganglion.Analysis of the data reveals striking trends of correlation between body size, volume of ganglia, and average cell territories. Since similar correlations have been described for other types of neuronal cell aggregates, it is suggested that for any given nucleus, ganglion or cortical area, the neuronal packing density varies as a function of body size.