bluuebunny/crossref_metadata_2025_split huggingface dataset:
Innervation of the hand muscles of Didelphis marsupialis virginiana, Kerr
Authors: Brandell Bruce R. 
Published: February 2005

AbstractAn investigation of the innervation of the hand muscles of the opossum, Didelphis marsupialis virginiana, Kerr, was made to determine the pattern of hand muscle innervation in a relatively primitive quadruped mammal. Four pairs of preserved opossum hands were dissected, and the innervation of their muscles studied with a stereobinocular microscope. The distributions of the median and ulnar nerves to the hand muscles are outlined, and the details of distribution are illustrated by means of seven diagrams.Peculiar anastomoses were consistently found between the superficial interdigital rami of the median nerve and branches of the deep volar ramus of the ulnar nerve, and the short deep flexors of digit II consistently received all, or a part, of their innervation from superficial interdigital rami of the median nerve. Five features of these unusual nerve connections and distributions are summarized and discussed.
A histochemical study of follicular atresia in the snake ovary
Authors: Guraya Sardul S. 
Published: February 2005

AbstractBy employing histochemical techniques, the follicular atresia and problems of interstitial cells have been worked out in the ovaries of two species of snakes (Naja tripudians and Bungarus coeruleus). Large follicles with a polymorphic granulosa show more atresia from September to November. Details of morphological and histochemical changes in the yolk nucleus substance, mitochondria and lipid bodies of oocyte and granulosa have been described. During atresia the theca interna is greatly hypertrophied and is loaded with lipids consisting of first phospholipids, then phospholipids and triglycetides and finally triglycerides, cholesterol and its ester and little phospholipids. Finally the oocyte, zona pellucida, granulosa cells and most of the cells of theca interna regress and disappear, leaving behind some residual cells of theca interna. The histochemistry of normal and atretic follicle of snakes and lizards has also been compared and contrasted with that in mammals. The “interstitial cells” of snake ovary have been discussed in the light of recent researches carried out on similar cells in the mammalian ovary.
Some observations on the anterior pituitary of the domestic fowl with the aid of the electron microscope
Authors: Payne Fernandus 
Published: February 2005

AbstractLipid accumulations in the gonadotrophs of the pituitaries of aging and castrate fowl have been demonstrated. Secretory granules and mitochondria play no part in their formation. Some lipids, perhaps all, occupy the cavities of the ER. The ER is a highly variable organelle, appearing as spherical or irregularly shaped vesicles in gonadotrophs or as lamellae in acidophiles. The Golgi complex is typical of pituitary cells in general. There are no bodies in the enlarged cavities of the complex and convincing evidence for the origin of all secretory granules within the small vesicles of the complex is lacking. Many secretory granules appear to be without membranes and to lie free in the cytoplasmic matrix. Observations on the pituitaries of broody hens confirm earlier conclusions that the broody cells appear during the incubation period and that they are small cells with large nuclei and reduced cytoplasm. The study also confirms the accumulation of secretory granules in laying hens at one side of certain cells which are interpreted to be either LH or FSH producing basophiles. Thiouracil feeding brings about some unexpected granular accumulations in the ER vesicles of thyrotrophs of the fowl pituitary. The granules may fuse to form larger structures with concentric rings. Whether the effect is direct or indirect through the thyroid is uncertain, but thiouracil feeding and thyroidectomy produce similar effects upon the pituitary. The interpretation of these changes remains to be determined.
Implant‐induced accessory limbs in urodeles: Fresh, frozen, and boiled tissues
Authors: Stevens J. , Ruben L. N. , Lockwood D. , Rose H. 
Published: February 2005

AbstractImplants were made into forelimbs of Triturus viridescens using fresh, frozen and boiled kidney and liver of T. viridescens and R. pipiens. Limbs were recovered at intervals up to 70 days post‐implantation.Kidney implants from Wisconsin R. pipiens gave twice as many extensive accessory structures as did Vermont frog kidney. Total induction percentages, however, were similar.Quantitative and qualitative parameters for implant‐induction of accessory structures were investigated. The decrease in antigenicity and increased rate of cytolysis of frozen implants resulted in increased similarity between frog and newt kidney in rate and pattern of breakdown and in rates of induction. Modification of rate and duration of the release of the stimulating factor from the implant did not result in induction by liver implants.No evidence was found for any increase in innervation prior to or coincident with blastema formation. Implantation and implant cytolysis may cause hypersensitivity of limb tissues to the normal innervation pattern or trophic stimuli from the implant may act with those from the injured limb tissues to produce growth.The general pattern of host reaction to the implanted material was studied and described.
The structure of the digital setae of lizards
Authors: Ruibal Rodolfo , Ernst Valerie 
Published: February 2005

AbstractLight and electron microscope studies of the digital lamellar setae of geckos and anoline lizards demonstrate that the free ends of the setae consist of flattened spatulas of less than 1 μ in width. The anoline setae are simple structures usually less than 30 μ in length and with a single terminal spatula to each seta. In contrast the setae of geckos are complex structures of about 100 μ in length, with numerous branchings, and having many spatulas per seta. The spatulas of Gekko and Aristelliger were smaller (0.2‐0.4 μ in width) than the spatulas of Anolis (0.8 μ in width). The electron microscope studies indicate that the scales of lizards appear to be covered with small epidermal spines (1.5 μ long). The setae of anoles and geckos are considered to have evolved independently from these more primitive epidermal spines. It is further suggested that the mechanism that allows the lamellae to adhere to the substratum is a surface phenomenon. The spatulas provide a large surface that is in contact with the substratum and thus produces a large total frictional force. The α layer of the lizard stratum corneum can be readily identified in the lamellae. However, the structure of the β layer is not easily interpreted and there is evidence of a fibrous layer between the Oberhautchen and the α layer in the skin of the outer lamellar surface.
The rat submaxillary salivary gland. A correlative study by light and electron microscopy
Authors: Tamarin Arnold , Sreebny Leo M. 
Published: February 2005

AbstractThe rat submaxillary salivary gland has five distinct parenchymal zones.
Acini consist of secretory and myoepithelial cells. An extensive network of canaliculi connect the many cells within an acinus to the main lumen. The fine structure of acinar secretory cells suggests that they are capable of great synthetic capacity; each cell having a large amount of ergastoplasm, many Golgi zones, and a great amount of secretory material. It is proposed that these cells are of the continually secreting type.
Intercalated ducts consist of cuboidal cells and myoepithelium. This segment connects the acini to the main conduit system of the gland. The fine structure of the cuboidal cells indicates that they are essentially nonsecretory.
The granular duct consists of three types of columnar cells; (a) dark narrow cells which contain many free ribosomes but no ergastoplasm or granules, (b) light granular cells which have varying amounts of ergastoplasm and granules, (c) dark granular cells which are full of granules while the other cell constituents including the nucleus, occupy a basal position. It is proposed that these three cells represent different secretory stages of the same cell type. This supports the interpretation that secretion in these cells is not continuous, but cyclic in nature.
The striated duct forms a small portion of the total gland parenchyma and consists of tall columnar cells with extensive infolding of the basal plasma membrane, relatively little ergastoplasm and very few granules. It seems likely that ion and water metabolism is a specialized function of this segment.
The excretory duct consists of three cell types: (a) tall columnar light cells, (b) dark columnar vesiculated cells and (c) small basal cells. The basal infoldings of these cells and the arrangement of many capillaries around these ducts suggests that this segment is primarily concerned with water transport.
The ultrastructure of the germinal epithelium of the mouse ovary
Authors: Wischnitzer Saul 
Published: February 2005

AbstractIt was demonstrated that the germinal (surface) epithelium around the mouse ovary consists of simple squamous, cuboidal and columnar arrangements of cells. With the electron microscope it was shown that these cells have the usual cytoplasmic constituents such as the Golgi complex, mitochondria, ergastoplasm, and free ribosomes. Their nuclei are surrounded by a bilamellar envelope with coarse granular masses of nuclear material being distributed along its inner surface. From the surface of these cells extend numerous microprojections which usually are irregular in squamous cells, but are villus‐like on the cuboidal and columnar forms. These microvilli appear to be simply extensions of the cell surface and apparently reflect the capacity of mesothelium for such specialization at its free surface. The intercellular boundaries are seen to consist of wavy, downward extensions of the plasma membrane or a complex irregular interdigitation of coarse lateral processes. The latter form is especially prominent between squamous cells. A membrane is present at the basal cell surface. The observations concerning the presence of microprojections and the nature of the intercellular boundaries were discussed in the light of the controversies on these subjects which appear in the early literature. The possible permeability of the germinal epithelium and its functional significance during maturation of the ovary were also discussed.
An analytical study of coitus in Aedes aegypti (Linnaeus)
Authors: Jones Jack Colvard , Wheeler Ronald E. 
Published: February 2005

AbstractPre‐copulatory behavior of male Aedes involves pursuit, tarsal contact, ventral orientation, and terminalial contact. Copulation itself involves seizure of the female's cerci by the male's claspers, extension of the male's paraprocts, erection of the aedeagus, and ejaculation. The male's ability to copulate is prevented by damaging or removing his seventh abdominal segment. If this segment is left intact, his freshly removed abdomen can copulate with a freshly isolated female's abdomen when their terminalia are rubbed together appropriately. The male's genital apparatus accurately “recognizes” the terminalium of an inseminated female, and forced‐copulation cannot be induced. The claws at the ends of the male's claspers are inserted into the bases of the female's cerci. The thumbs of the apical paraprocts of the male fit into a temporary coital cavity within the upper vagina. The hooks of the male's apical paraprocts are inserted into the female's cloacal hollow. The teeth on the distal end of the aedeagus ratchet into the teeth on the dorsal vaginal valve and evert the upper vagina. The posterior ends of the seminal vesicles and accessory glands open and contractions of these organs release seminal material only into the bursa of the female.
The structure of bone marrow. Functional interrelationships of vascular and hematopoietic compartments in experimental hemolytic anemia: An electron microscopic study
Authors: Weiss Leon 
Published: February 2005

AbstractIn hematopoietic marrow, sinuses form a system of vessels running radially from the periphery toward the central longitudinal vein. Hematopoietic tissue, having the form of cords, lies between the sinuses.The wall of the vascular sinus of the marrow, in fullest development, is trilaminar. It consists of a lining cell, basement membrane and adventitial cell. It may, however, consist of lining cell alone. Occasionally, the wall is bilaminar, made up of lining cell and basement membrane, or lining cell and adventitial cell. The adventitial cell and lining cell are reticular cells and may exactly resemble one another. But often the adventitial cell, and occasionally, the lining cell of a sinus may be very voluminous and rarefied, extending among the hematopoietic cells. The mural reticular cells, particularly the adventitial cells, may be phagocytic. The adventitial cells, moreover, contain fat droplets, and may accumulate the unilocular fat deposit characteristic of a fatty marrow.Megakaryocytes lie outside the sinus discharging platelets through mural apertures. In places, fairly large segments of sinus wall may become attenuated, pierced by apertures and, perhaps, drop out, with the result that the sinus is enlarged. Normo‐blasts, reticulocytes and myelocvtes enter the circulation by passing into a sinus. Three mechanisms are present: (1) They may pass through existing apertures or (2) create an aperture by pressing into a sinus wall. (3) A segment of wall may drop out setting heretofore extravascular cells into the circulation.Adventitial spurs or processes extend from the sinus into the perisinus tissue. These spurs are of the same structure as the sinus wall. The perisinus tissue, present as cords between sinuses, is typically filled with hematopoietic and other free cells. The adventitial processes, together with the reverse surface of the sinus walls, incompletely bound the intersinus hematopoietic cords. The intersinus space may thereby have the same contour as sinuses. They differ from sinuses in containing many hematopoietic cells and in being less completely bounded by wall.It is postulated that the sinuses and intersinal cords form a reciprocating system wherein portions may become vascular (sinal) or extravascular (cordal) depending upon the requirements for hematopoiesis, blood flow, blood storage and delivery of cells to the blood. The reciprocation is effected by the ready capacity of sinal walls and adventitial spurs to take form, change disposition and break down.
Femoral glands of the lizard, Crotaphytus collaris
Authors: Cole Charles J. 
Published: February 2005

AbstractThe anatomy of the femoral glands in an iguanid lizard, Crotaphytus collaris collaris (Say), is described. The 48 lizards (including three embryos) from which glands were examined were obtained throughout their season of activity at one locality in Kansas.In animals of both sexes the glands lie in a linear series on the ventral aspect of each thigh. They are composed of branching tubes and tubules of epidermal and dermal origin. The row of femoral pores is the only external manifestation of the glands.Post hatching, the glands of males increase in size and complexity; little onto‐genetic change occurs in the glands of females.The relative length of the glands appears to vary seasonally in adult males suggesting variation in their activity. The greatest relative sizes occur in the breeding season.At times a stratum corneum, continuous with the stratum corneum of the skin, occurs in the duct of the gland internal to part of the secretion plug. Formation of the stratum corneum seems to be initiated in the autumn prior to hibernation, and the stratum corneum removes the outer part of the secretion plug in the next ecdysis; meanwhile, production of a new secretion plug is initiated.The anatomy of the femoral glands in Crotaphytus is similar to that of the described glands of other species of lizards.
The structure and formation of the cuticulin layer in the epicuticle of an insect, Calpodes ethlius (Lepidoptera, Hesperiidae)
Authors: Locke Michael 
Published: February 2005

AbstractThe cuticulin layer is defined as the dense lamina (120–175 Å thick in Calpodes larvae, depending upon the stage) forming the outer part of the epicuticle in insects. It completely invests an insect except for the gut and the openings of some sense organs. It is the first layer to be secreted during the formation of new cuticle. The formation of the cuticulin membrane may be a useful model for studying the origin of membranes in general. It arises as a triple layer de novo and is not a modified plasma membrane. Growth is by accretion at the edges of patches of cuticulin which increase in area until they cover the new surface. The triple layer (i.e. three dense laminae) may develop striations about 30 Å apart transverse to the membrane, which perhaps form a sieve allowing small molecules to pass while protecting the cell from enzymes in the molting fluid. A similar porous structure persists in the tracheoles. After the resorption of molting fluid the triple layered structure again becomes obvious and the outermost layer separates from the other two to become what may be the surface lipid monolayer. The surface patterns in cuticle of various sorts probably arise by buckling of the cuticulin layer as it increases in surface area.
Response of hair types in mice to higher doses of x‐rays
Authors: Galbraith Donald B. 
Published: February 2005

AbstractDoses of x‐rays exceeding 1,000 r delivered to resting hair follicles of mice cause a variable greying response ranging from 60 to 100%. The purpose of this study was to study this phenomenon with specific reference to the response of zigzags and overhairs to irradiation. Accordingly, mice were exposed to 1,200 r and 1,300 r of x‐rays and the response of hairs from a known area was compared with that of unirradiated controls and mice given 600 r, 800 r and 1,000 r, of radiation. It was found that at the higher doses, variations in total greying response were paralleled by variations in the response of both zigzags and overhairs, that there is relatively greater epilation of overhairs, and that zigzags contribute most heavily to both the white and the totally pigmented fractions. The results of this study therefore do not support the previous suggestion that the variable greying response is a function of a relative increase of pigmented overhairs in conjunction with selective damage of zigzags.
The megachiroptera and vespertilionoidea of the microchiroptera
Authors: Pye Ade 
Published: February 2005

AbstractThe structure of the external ears and the ultrasonic cries produced by one member of the single family of Megachiroptera and six representatives of the Vespertilionoidea of the Microchiroptera have been described. All the specimens were intra‐vitally fixed and the preparations have been examined, photographed and measured. Brief notes are given on the middle ear and the following measurements have been made on the cochlea: the general size of the cochlea in various dimensions, the width and thickness of the basilar membrane, the size of the spiral ligament and the height of the cells of Claudius. In conclusion it can be said that there are marked differences in the structure of the cochleae of the two suborders, as well as within the superfamily Vespertilionoidea.
Some observations on spermatogenesis in Gelastocoris oculatus (hemiptera) with the aid of the electron microscope
Authors: Payne Fernandus 
Published: February 2005

AbstractThe nuclear cap in the spermatogonial and early spermatocyte cells of Gelastocoris is an aggregate of closely packed mitochondria with their long axes perpendicular to the nuclear membrane. Eventually in the early growth period, the mitochondria move from the cap and appear to become more or less equally distributed in the cytoplasm where they remain until their fusion in the spermatid to form the nebenkern. The Golgi complex consists of clusters of lamellae and vesicles, the Golgi bodies. Granules form within the vesicles, increase in size, move from their place of origin and become distributed at random in the cytoplasm. They are the pro‐acrosomal granules and at the end of the growth period fuse to form the proacrosome, about which Golgi bodies collect. The Golgi bodies, however, never fuse into an acroblast. At one end of the oval‐shaped pro‐acrosome is a small dark body and a less dense vesicle the future of which is uncertain. The dark body eventually occupies a position at the tip of the acrosome. The pro‐acrosome, after moving to the side of the nucleus opposite the nebenkern, differentiates into the acrosome which elongates into a tail‐like structure. The nuclear membrane of some spermatocytes may appear wave‐like in cross section, with the crest and trough different in appearance. Near the membrane and in the troughs of the waves large clusters of granules are frequently present. Similar clusters may be found elsewhere in the cytoplasm. Presumably they had their origin near the membrane but this is not conclusive. Bodies of indeterminate origin and structure may be present in the cytoplasm. They could be lysosomes but evidence is lacking. In late spermatocytes and in spermatids, a group of ten or twelve granules is present. They are smaller than the pro‐acrosomal granules, are always closely associated and pass as a group into the tail. Their significance is unknown. The endoplasmic reticulum is typical of cells in general. There are no granule accumulations within the vesicles as in some secretory cells. Vesicles of various shapes and sizes are present within the centrosphere of the first meiotic division. While their location is similar to that of the centriole, the identity of the vesicles is uncertain.
Fine structural organization of the rectum in the blowfly, Calliphora erythrocephala (Meig.) with special reference to connective tissue, tracheae and neurosecretory innervation in the rectal papillae
Authors: Gupta Brij L. , Berridge Michael J. 
Published: February 2005

AbstractThe rectal epithelium of Calliphora is made up of three quite distinct cell types: rectal, cortical and junctional cells.The thin wall of the rectal pouch is made up of rectal cells which are relatively simple and unspecialized; their general structure does not suggest any direct participation in ion transport.A function of ion and water transport can probably be ascribed to the cortical cells, which are arranged in the form of four cones which project into the rectal lumen. The cavity of each cone is filled up with tracheae, nerve and neurosecretory terminals, and connective tissue to form medulla. The medulla and cortex are separated from each other by deeply staining bridges or trabeculae to form an infundibular space. The most conspicuous feature of the cortex is the presence of an extensive intercellular sinus formed by complex infoldings of the lateral plasma‐membranes. It is postulated that fluid, which is absorbed from the rectal lumen, is transported into the intercellular sinus and finally reaches the haemolymph via the infundibular space. The actual site of ion transport is probably the stacks of lateral plasma‐membrane which are closely associated with mitochondria.The junctional cells, which are packed with microtubules, form a collar around the base of the papillae at the point of their insertion into the rectal wall.It is suggested that the neurosecretory terminals present in the medulla might release a hormone which controls rate of ion and water reabsorption by the papillae cells.