bluuebunny/crossref_metadata_2025 huggingface dataset:
Morphogenetic studies of the rabbit. XXXIX. Ponderal correlation coefficients of the bones form two races of rabbits
Authors: Latimer Homer B. , Sawin Paul B.
Published: February 2005

Thirty‐five male an 30 female rabbits of large race III derived from the New Zealand White race and the same numbers of small race X, from Castle's small race, were used in this study.

Earlier studies on these two races have shown that the males are more variable in body weight and body length; and that the individual bones are likewise more variable in weight and in length in the males.

In this study, body weight and the weight of the entire skeleton were correlated on the basis of the null hypothesis with the individual bone weights and the individual bone weights were intercorrelated. The correlations are, for the most part, higher in the males than in the females of both races. The males of small race X have higher correlations than the males of large race III.

Thus, although the entire body size varies more in the males. the weights of the bones are, for the most part, more closely correlated with body weight and total skeletal weight and with the other bones in the males than in the females.

Some of the lowest correlations are with bones having large proportions of cancellous bone.
An electromyographic study of some muscles crossing the elbow joint
Authors: Pauly John E. , Rushing James L. , Scheving Lawrence E.
Published: February 2005

Pairs of fine wire electrodes were inserted into the lateral, medial and long heads of the triceps brachii, into the anconeus, biceps brachii, brachialis and brachioradialis muscles. Each pair of electrodes was connected to an EMG integrator coupler in an eight channel recorder. Many movements and exercises were studied, and the relative contribution made by each muscle to any given movement was appraised.

The anconeus initiates extension of the elbow and acts to maintain extension and to stabilize the elbow joint during other motions involving the upper extremity. The anconeus is responsible for fine control, but its activity frequently decreases when the more powerful triceps brachii contracts or when it loses its mechanical advantage at full extension. In pronation, the anconeus is very active; whereas during supination the anconeus is less active, and the triceps counteracts the powerful pull of the biceps brachii.

The long head of the triceps also works as an adductor of the arm. When the triceps assists the anconeus in stabilizing the joint, the biceps brachii, brachialis and event the brachioradialis may contract to counteract any tendency to further extend the joint.
Weights and variability of components of the human vertebral column
Authors: Lowrance E. W. , Latimer Homer B.
Published: February 2005

Principal vertebral segments and individual vertebrae of 83 Asian skeletons were weighed and the data treated statistically.

Average weight in grams per unit vertebra in the cervical segment was 6.3, in the thoracic, 8.7, in the lumbar, 17.9 and in the sacrum, 10.6. Mean weights of segments of this series were the lightest of the populations compared except those of the American White and Japanese females. Individual vertebral weights increased in caudad sequence except that the first two cervical and first two thoracic were respectively heavier than the third cervical and third thoracic. Mean weights of the twelfth thoracic, fifth lumbar and the sacrum were approximate multiples of that of the seventh cervical. The third cervical was the lightest in the column.

The cervical segment represented 15% of the weight of the entire column, the thoracic segment 36%, lumbar 31%, sacral 18% and coccygeal 0.4%. Relative weights of individual vertebrae corresponded closely with those of other populations compared.

Coefficients of variation ranged from 16% in the cervical segment, 19% in the thoracic, 17% in the lumbar, 18% in the sacral to 48% in the coccygeal. Variation was least in the second cervical and greatest in the third thoracic vertebra.
The passage of exogenous peroxidase from blood capillaries into the intestinal epithelium
Authors: Hampton James C. , Rosario Benjamin
Published: February 2005

Horseradish peroxidase was injected into the spleens of mice and the animals were sacrificed ten minutes after injection. The tissues were reacted with 3‐3′ diaminobenzidine hydrochloride and the distribution of the reaction product was studied with both the light and electron microscope. The peroxidase was localized between epithelial cells up to the region of the tight junction and within vacuoles in the absorptive cells Granules ranging in size from ca. 40A to 600A were observed in the cytoplasm of epithelial cells in numbers far in excess of that found in control specimens. It appeared that the diffuse light brown staining observed in epithelial cells with the light microscope could be attributed to large numbers of granules of reaction product free in the cytoplasm. When corn oil was given by stomach tube and an intravascular injection of perioxidase was given ten minutes later, absorbed lipid was found to pass from interepithelial cell spaces to lamina propria at the same time that peroxidase was traversing the same compartments in the reverse direction. Hence, it was shown that exogenous peroxidase and probably other substances of vascular origin required for the metabolism of epithelial cells are exposed to both the basal and lateral epithelial cell membranes, even when absorbed lipid is traversing the same spaces in the opposite direction.
The juxtaglomerular apparatus in fetal and newborn mice
Authors: Kaylor C. T. , Carter J. M.
Published: February 2005

Kidneys of timed fetal and newborn mice of the C57BL stock were sectioned and stained with a modified Bowie technique. The juxtaglomerular cells, indentifiable by their granularity and position, were recognized rather late in fetal life — three or four days before birth. By the eighth day postpartum, the granular cells of the JGA had reached a peak of differentiation and closely resembled the adult JGA in their number, size, granularity, and position. The mesangial cell was often but not always granulated. The granular cell indices (G.C.I.) of fetal, newborn, and adult mice are compared. The high G.C.I. in fetal kidneys in our studies should account for the high renin titre found by others in fetal kidney extracts.
Lymphotaxis induced by ultraviolet microbeam irradiation of fibroblasts in tissues cultured from mouse embryos
Authors: Amenta Peter S.
Published: February 2005

When portions of the cytoplasm of fibroblasts cultured from mouse embryo tissues are irradiated with heterochromatic microbeams of ultraviolet light, lymphocytes are attracted (Lymphotaxis) to the injured areas. The lymphocytes approach in the “hand mirror” shape characteristic of tissue cultures. On reaching the fibroblast, pseudopodia shoot out to “lick” the wound and then the lymphocyte “worms” its way across the cell. Only one lymphocyte contacts a fibroblast but the same one may make several passes. It is postulated that lymphocytes are cleaning the wounded area of undesirable irradiation products and/or applying healing substances to the wounded fibroblast.

Irradiation of lymphocytes in portions of the cytoplasm fails to evoke responses from nearlby lymphocytes. Instead, the cytoplasm whirls around the nucleus as if the irradiation products can not leave the cell, resulting in convulsions and death.

A technique is described by which relatively pure cultures of lymphocytes may be obtained from leukocyte cultures by selectively killing all granular leukocytes with excessive exposure to microbeams of ultraviolet light. Lymphocytes are harvested and introduced into fibroblast cultures to study experimental lymphotaxis.
Endometrial and embryonic enzymes in relation to implantation of the rabbit blastocyst
Authors: Hafez E. S. E. , White I. G.
Published: February 2005

The activity of alkaline phosphatase, acid phosphatase, glutamic‐oxalacetic transaminase (GOT), lactic dehydrogenase (LDH), amylase, succinic dehydrogenase (SDH), glucose‐6‐phosphate dehydrogenase (GD) has been determined in the rabbit endometrium at estrus, in pseudopregnancy, and at days 5–10 of pregnancy. Enzyme analyses were also made on the placenta and embryo during early pregnancy.

The most striking changes were increases in the SDH and GDH levels of the endometrium and a decrease in amylase when the does became pregnant or pseudopregnant. Amylase did not rise significantly from its lower level between five and ten days of pregnancy; SDH and GDH activity, however, fell away after reaching a maximum prior to implantation. At implantation there was some evidence of an increase in LDH and phosphatase activity. All enzymes had lower activities following implantation (10 days pregnancy). The endometrial enzyme activities of prepubertal does were usually similar to those of adult females in estrus. However, alkaline phosphatase activity of the prepubertal endometrium was particularly low.

The activity of enzymes in the placental areas were, in general, similar to those found in the interplacental areas of the endometrium. However, from 7–10 days of pregnancy the activity of SDH was lower in the placental area than in the interplacental areas; whereas, amylase was higher on the eighth and ninth days of pregnancy. Changes in the activities of the phosphatases, GOT and SDH occurred in the blastocyst and trophoblast on eight to ten days of pregnancy. Enzyme activities in blastocoelic fluid were much less than in the trophoblast with the exception of amylase which was higher.
Effects of cadmium upon the excurrent duct system of the rat testis
Authors: Mason Karl E. , Young James O.
Published: February 2005

This report describes lesions observed in excurrent ducts of the testis in 152 of 518 rats, in the course of studies concerned with cadmium‐induced testis injury and the actions of selenium and zinc, separately and combined, in protecting against such damage. All elements were injected subcutaneously, as soluble salts. Necropsy was usually five days (77% of rats) after cadmium injection, but lesions were observed within six hours.

Ductuli efferentes showed variable degrees of sperm blockage, epithelial hyperplasia and metaplasia, periductal round cell infiltration, fibrosis and contraction. In 56 of 93 rats showing only ductuli lesions, testes were either normal or exhibited dilation of the rete testis and of variable numbers of seminiferous tubules, with or without “pressure degeneration” of the germinal epithelium. In the other 37 rats, the testes showed cadmium‐induced injury.

Lesions involving both ductuli efferentes and proximal segments of the caput epididymis (13 rats), or the latter alone (46 rats), tended to be associated with more severe testis damage. Epididymal lesions were characterized by focal proliferation and desquamation of duct epithelia, and formation of spermatoceles.

The lesions observed were attributed primarily to ischemia, secondary to effects of cadmium upon the capillary bed of the tissues involved. However, their possible enhancement or modification by direct chemical action of cadmium, selenium or zinc upon the duct system or perivascular tissues could not be excluded.
Myocardial ultrastructure and electrocardiograms of the hummingbird under normal and experimental conditions
Authors: Didio Liberato J. A.
Published: February 2005

Ventricular myocardium from several adult specimens of hummingbirds (Eupetomena macroura macroura) were subjected to study by electrocardiography and by light and electron microscopy under normal and experimental conditions as provided by injection of 2,4‐dinitrophenol (DNP) and ether anesthesia. The birds were captured in Brazil, and were studied because of their high heart rates 428/460 minute on the average, seeking correlations of structure and function under normal conditions as well as after pharmacological stimuli. Under normal conditions, the hummingbird showed a highly developed sarcoplasmic reticulum, many gigantic mitochondrial with numerous tightly packed parallel mitochondrial cristae and tubules, and few small, dark bodies. The amount of sarcosomes is approximately equivalent to that of myofibrils. As seen in longitudinal sections of muscle fibers, often the junctions between successive mitochondria and both indentations of mitochondria and of the nuclear envelope occurred at the level of the Z bands. This gave the impression that contraction of the myofibrils shortened the nucleus and caused it to wrinkle. Most mitochondrial bulged at their middle as if they had been compressed between successive Z bands, suggesting a more resistant area at the level of these bands than in the rest of the myofibril. Almost no glycogen granules were found, probably because the high metabolic rate of the heart did not allow free storage of such carbohydrates.

The administration of DNP was responsible for changes in the ECG (tachycardia and other alterations) and in the structure of the myocardium: large dilations in the sarcoplasmic reticulum and the appearance of small spaces in the mitochondria.
The effect of thiouracil, excess thyroxine and thyroidectomy on the ependymal cells with special reference to the subcommissural organ
Authors: Talanti S.
Published: February 2005

The effects of excess thyroxine, thiouracil and thyroidectomy upon the ependymal cells of the subcommissural organ, the choroid plexus and the wall of the caudal part of the third cerebral ventricle in the adult male albino rats were studied. A total of 203 rats were used. Thiouracil and thyroxine were administered orally, thyroidectomy was performed by means of radioiodine. Thiouracil was seen to diminish the ependymal nuclear volume especially in the subcommissural organ and in the wall of the third ventricle. Similar effects were observed by thyroidectomy, though the change was significant only in the ependyma covering the wall of the third ventricle. Excess thyroxine, again, increased nuclear volume of all ependymal cells studied. The changes could be observed over a period of 4–18 days. The signs of a return to normal after withdrawal of thyroxine and thiouracil were perceived after four days. Visual estimation revealed no clear change in aldehyde‐fuchsin‐positive “secretory material” in the subcommissural organ of any test group. The functional significance of the results is discussed.
Reconstruction using photographed serial sections
Authors: Berns Michael W.
Published: February 2005

A method is described whereby serial sections are photographed through a microscope and printed on a clear acetate film. The pictures are mounted on Plexiglas rectangles and placed back to back. A solid stack of plates with the reconstructed structure visible inside, or a slide‐box arrangement of every other section may be produced. Variations of the technique are presented so that one can print high‐contrast or low‐contrast pictures, reconstruct simple or complex structures, and work more rapidly with less equipment. This is a simple, accurate, and rapid method.
A quantitative morphological study of the postnatal development of the pineal body of the mouse
Authors: Ito Takashi , Matsushima Shoji
Published: February 2005

The postnatal growth of the mouse pineal was studied quantitatively. The volume was estimated by means of a histometric method in serial histological sections. During postnatal development the pineal showed no sex difference in absolute size. The growth in volume gradually increased from birth to 40 days, reamained the same for a short period between 40 and 60 days, and after 60 days again increased until 90 days when it finally attained the adult volume. From 90 to 210 days it remained almost constant.

The pineal weight was calculated from the volume by means of a weight‐volume ratio of the cerebral tissue. The pineal growth during early postnatal period, especially the first ten days, is attributed to both proliferation and enlargement of pineal cells, but after 20 days, primarily to enlargement. Differentiation of the pineal was estimated quantitatively on the basis of nuclear changes in shape characteristic of the pineal cells.
Arteritis of coronary arteries in mice receiving a single dose of cortisone
Authors: Ashburn Allen D. , Williams W. Lane , Smith‐Vaniz George T.
Published: February 2005

Mice were given a single injection of cortisone acetate and killed from one to seven days later. Arterial lesions occurred first and were predominantly located in the right ventricle. Hyalin was present in media of these coronary arteries within 24 hours following administration of cortisone. Exudative and proliferative changes in the arterial walls and perivascular spaces followed medial hyalinization. The highest incidence of arterial lesions (90%) was attained on the third day following cortisone injection and then decreased slightly (57%) by the seventh day. Myocardial necrosis was observed first in mice killed 48 hours after receiving cortisone and the incidence did not change significantly thereafter.
Electron microscopic observations of non‐specific lead staining in the smallintestine of the cat after lipid or carbohydrate feeding
Authors: Napolitano Leonard , Howard John
Published: February 2005

A series of experiments utilizing the technique of Rostgaard and Barrnett which purported to demonstrate lead‐lipid complexes was performed to study the efficacy of using lead as a marker in lipid absorption.

The jejunal mucosa from adult cats fasted 48 hours and fed corn oil by stomach tube was fixed in buffered glutaraldehyde for two hours, washed in cacodylate buffer and then incubated for 20 minutes in tris‐maleate buffer (pH 7.2) which contained 4mM of lead nitrate. Following osmication, dehydration and embedding in Epon, thin sections, either stained or unstained were examined in an electron microscope. Lead deposits of varying size were observed in, on and about the microvilli. In addition, lead deposits were observed related to mucous cells. The jejunal mucosa of cats fasted 48 hours and fed 5% dextrose and treated as the lipid‐fed animals gave similar results. Fasted animals had few lead deposits related to the gut epithelium.

When jejunal mucosa from lipid‐ or carbohydrate‐fed animals was extracted in lipid solvents prior to incubation in tris‐maleate containing 4mM of lead nitrate, the lead densities persisted.

In view of the foregoing, the occurrence of lead precipitates following a fatty meal does not offer an unequivocal means of tracing lipid absorption in the small intestine.
Transformation of rat small lymphocytes with pokeweed mitogen (PWM)
Authors: Schwarz M. Roy
Published: February 2005

When lymphoid cells from the thoracic duct lymph, blood, lymph node, spleen and thymus of the rat were exposed to pokeweed mitogen (PWM), large primitive cells appeared after 24–30 hours of culture. This response was not limited to tissues of adult animals but was also demonstrated in cultures of cells from the thymus glands, lymph nodes and spleens of newborn, 48 hour and three‐day‐old rats, respectively. The transformed rat cells, in contrast to the cells observed in human PWM cultures (Chessin, Bőrjeson, Welch, Douglas and Cooper, '67), could not be divided into two populations on the basis of cytoplasmic basophilia, PAS positive granules or alcian blue staining. In addition, the thoracic duct lymphocytes from rats thymectomized within 24 hours of birth showed a marked deficiency in transformation, characterized by decreased numbers of enlarged cells and minimal cytoplasmic basophilia, when compared to similar cells from non‐operated or sham‐thymectomized controls.

In the thymus cultures, some of the small lymphocytes served as precursors of the transformed cells without undergoing division. Subsequently, these enlarged cells proliferated giving rise to small lymphocytes and additional transformed elements. Exposing lymphoid cells to PWM for up to 14 days did not result in the development of plasma cells.
A histochemical study of mucoid cells in the Pars distalis of the human hypophysis
Authors: Conklin James L.
Published: February 2005

Sections of the human hypophysis were fixed in either formalin or Bouin's fluid and stained by a variety of mucoid and acid stains in order to demonstrate the staining characteristics of the mucoid cells of the pars distalis.

Five types of mucoid cells were revealed and designated as cell types III, IV, V, VI and IX according to the classification system of Ezrin. Cell types III, IV, V and VI were present throughout the pars distalis while cell type IX was observed only in the posterior zone.

The cells were tinctorially distinguished by the PAS‐orange G affinity of the type III cell, the alcian blue‐PAS reactivity of the type IV cell, the alcian blue staining of the type V cell and the affinity of the type VI cell for alcian blue‐PAS‐orange G. Cell type IX was recognized by the affinity of its cytoplasmic granules for most of the stains employed. Modified and degranulated forms of these cells were observed and are also described.
Development of pancreases and adrenals of rat embryos in organ culture
Authors: Wells Lemen J. , Erlandsen Stanley L. , Eguchi Yasunobu
Published: February 2005

Developing pancreases from rat embryos of the sixteenth day of pregnancy and adrenals from embryos of the nineteenth day were grown in organ culture for six days. The cultures were transferred to fresh media twice, after 48 hours and after 96 hours of incubation. Control cultures consisted of pancreas alone and of adrenal alone.

The pancreatic islets which were too young to have granulated beta cells on the sixteenth day of pregnancy differentiated into islets with many granulated beta cells during the culture period of six days. The pattern of granulated beta cells and the estimated number of these cells in cultures with adrenals were variable (not consistently different from those in the control cultures without adrenals).

The adrenals from embryos of the nineteenth day had two zones of the fetal cortex outer and inner. Cultures of adrenals survived. The adrenals, whether minced or unminced at the time of the explantation and whether cultured alone or with pancreases, underwent little if any additional differentiation during the culture period.
Distribution of thyrotrophic activity in the hypophysis of necturus before and after thyroidectomy as measured by I131 bioassay in mice
Authors: Aplington H. W. , Tedrow Brant W.
Published: February 2005

Hypophyses of non‐thyroidectomized and thyroidectomized winter Necturi were divided into rostral and caudal portions which were frozen‐dried refrigerated, and injected into mice for bioassay according to the method of McKenzie' ('58). Each mouse received the homogenized equivalent of two pituitary portions, either rostral or caudal. The per cent increase in blood I131 which resulted was used as a gauge of thyrotrophic activity.

In the non‐thyroidectomized Necturus, nearly two‐thirds of the thyroid stimulating activity was in the rostral portion which consisted of the rostral two‐thirds of the anterior zone tissue. The remaining TS activity was in the caudal portion which consisted of the caudal third of the anterior zone, the transitional zone and basophilic bed area. These bioassay results coincide with the distribution of basophile cells described previously as thyrotrophs on the basis of histological observations.

After thyroidectomy, caudal portions yielded 95% of the thyrotrophic activity. This observation is consistent, with some reservation, with the number and distribution of thyroidectomy cells that differentiate after thyroidectomy, taking into account the vacuolation and degranulation of these cells which occurs in rostro‐caudal sequence.
Nuclear elimination from the normoblast of fetal guinea pig liver as studied with electron microscopy and serial sectioning techniques
Authors: Campbell Ferrell R.
Published: February 2005

The process of denucleation in normoblasts of fetal guinea pig liver was studied with electron microscopy employing serial sections. In the late normoblast the nucleus becomes eccentrically located in the cytoplasm. Continued maturation results in a nucleus which is protruding from the normoblast. Still later the nucleus separates from the remainder of the cell and is phagocytized by a reticular cell. Nuclei which have been extruded are surrounded by a narrow border of cytoplasm and possess a nuclear envelope, nuclear pores, and internal nuclear structure similar to that of normoblasts. The cytoplasmic border and nuclear structure are observed for some time after ingestion by reticular cells. Dissolution of nuclei inside the phagocytes is characterized by disappearance of the cytoplasmic border and nuclear envelope, loss of density of the chromatin, and appearance of dense particles in the interchromatin. It was concluded that under normal conditions, the sole mechanism of denucleation in definitive erythroblasts is extrusion. Mitochondria are partially degraded inside the late erythroblasts, forming a membranous residue which is later extruuded.
The vertebral level of the arytenoid cartilages
Authors: Koppel Harold J. , Kendrick George S. , Moreland James E.
Published: February 2005

A group of 27 females and 24 males between the ages of eight years four months and 15 years seven months was examined to determine the vertebral level of their arytenoid cartilages. An apprasial of their lateral cephalometric radiographs which included the cervical vertebra was made under rigid conditions. Each cervical vertebra was divided into three sections in order to relate its position more precisely to the cartilages. The age of each subject was recorded and then compared with the vertebral level of their arytenoid cartilages. General consistency seemed to prevail throughout the group at given sex and age levels. Visualization of the arytenoid cartilages was excellent. No evidence of mineralization in the laryngeal cartilages was noted in the age group studied.
Effects of estrogen on pituitary morphology in goitrogen treated rats. An electron microscopic study
Authors: Potvliege Paul R.
Published: February 2005

The influence on pituitary cytology of propylthiouracil (PTU) and estradiol benzoate (EB) administered singly and in combination was studied by electron microscopy in adult female rats. PTU alone induced striking changes in the morphology of thyrotroph cells, which were all transformed into typical thyroidectomy cells, characterized by enormously dilated ergastoplasmic sacs; the acidophils were degranulated and some of them took the appearance of relatively quiescent prolactin cells rather than degranulated somatotrophs. EB alone caused no definite changes in the morphology of thyrotroph cells; its essential effect was the development of a large number of prolactin cells. When both treatments were combined, thyroidectomy cells were found, existing side by side with untransformed thyrotrophs and exhibiting less dilated ergastoplasmic sacs than after PTU alone; prolactin cells were present in great number and showed a more developed ergastoplasm than after EB alone. Thyroid weight and height of the follicular cells were not changed by EB given singly; they were both increased under the influence of PTU; thyroid weight but not mean height of the follicular cells was slightly less increased when EB was added to PTU. It is tentatively concluded that estrogen may have a dual action on the thyro‐pituitary axis: on one hand, a depressing influence on thyrotroph cells and on the other hand a direct stimulatory effect on the thyroid gland.
Fine structure of the carotid body of normal and anoxic cats
Authors: Al‐Lami Fadhil , Murray Raymond G.
Published: February 2005

Certain modifications and clarifications of current concepts of the fine structure of the carotid body are described. The two principal cell types are here designated “enclosing” and “enclosed” to emphasize the enveloping nature of the former. The enclosed cells have numerous processes, contain lysosome‐like bodies which are sometimes related to crystals with a period of about 100Å. In addition to the typical dark‐cored vesicles, a few with lighter content are always present. The enclosing cells are in most respects similar in their contents to the enclosed, even to the presence of occasional dark‐cored vesicles. The fenestrations of the blood vessels apparently are closed by thin diaphragms.

In addition to the type of nerve endings previously described, there is a second type which extensively surrounds the enclosed cells, in the manner of a basket, and differs from the first type in having relatively empty cytoplasm with few synaptic vesicles or mitochondria. It is postulated that this is the afferent ending, while the former may be efferent.

Severe anoxia rendered both cell types more dense than normal. In contrast to previous reports, the dark‐cored vesicles of the enclosed cells did not disappear but rather increased in relative number, and their mitochondria were less opaque. No comparable changes were noted in control anoxic tissues of liver, kidney or adrenal medulla. The possibility is discussed that the enclosing cell has more than a simple supportive function, as the usual name “sustentacular” seems to imply.
Central distribution of trigeminal primary afferent fibers in anuran amphibians
Authors: Joseph Barry S. , King Robert B. , Whitlock David G.
Published: February 2005

Trigeminal ganglia were unilaterally macerated manually through the foramen ovale in three forgs. Rana catesbeiana, and in two toads, Bufo marinus. Following a two to three week post‐operative survival, each animal was anesthetized and was systemically perfused with formalin. Serial transverse frozen sections, 50 μ in diameter, were then prepared from the CNS of each animal. Selected tissue sections were stained according to a uranyl nitrate modification of the Nauta silver technique. The distribution of degenerating fibers was subsequently assesed by microscopic analysis.

Degenerating trigeminal fibers could be traced from the trigeminal root into the vicinity of the chief sensory nucleus of the trigeminus and into the spinal V tract and nucleus in both toad and frog. The spinal V tract passed into the cervical spinal cord in all animals but did not pass further caudally than the third spinal segment. In some animals, degenerating fibers passed into the fasciculus solitarius and the nucleus solitarius. No trigeminal primary afferent fibers could be followed into the cerebellum or into the immediate vicinity of any of the cranial motor nuclei, in cluding the trigeminal motor nucleus. The distribution of Gasserian ganglion collaterals recorded in this study is discussed with reference to previous findings in the trigeminal systems of amphibians, birds and mammals.
Reproductive organ DNA and RNA of male and female rats from birth to 100 days of age
Authors: Desjardins C. , Macmillan K. L. , Hafs H. D.
Published: February 2005

Male and female rats were adjusted to six pups per litter and weaned at 20 days of age. Groups of ten males were killed at five‐ to ten‐day intervals between one and 100 days of age and groups of 12 to 45 females were killed between ten and 100 days. Accumulation with age of gonadal, seminal vesicular, and uterine weight, DNA, and RNA, were compared with body growth in relative growth analyses to delimit puberty and quantify reproductive growth.

Males and females possessed similar body growth to 40 days, after which age females grew more slowly while males continued rapid growth to 60 days. Relative to body growth, testes grew more rapidly from ten days whereas ovarian growth generally paralleled body growth until 50 days of age. A shift in gonadal RNA/DNA ratio from less than to greater than unity occurred early in puberty in both sexes. Nucleic acid contents of accessory reproductive organs indicated that effective levels of gonadal steroids promote pubertal growth beginning at about 40 days in males and about 33 days of age in females. These marked pubertal growths ended at 70 days in males and 60 days of age in females.
Vascularization and basement membranes of the chick brain in light microscopy
Authors: Peterson Richard G.
Published: February 2005

Blood vessels were first observed in the hindbrain of chick embryos at stage 20 (three to three and one half days incubation). At this time the central nervous system had a complete PAS‐positive basement membrane. The surrounding blood vessels did not have a similar investment. An attenuated basement membrane, continuous with the one on the nervous tissue, enveloped each invading vessel. Invading vascular sprouts entered as solid cords which soon developed lumens and became functional capillaries.
Localization and distribution of adenosine triphosphatase activity in the femurs of young mice
Authors: Severson Arlen R. , Tonna Edgar A. , Pavelec Mildred
Published: February 2005

The localization and distribution of ATPase activity in the femurs of young mice was evaluated using the lead‐ATPase histochemical method. The skeletal system demonstrated an intracellular distribution of ATPase activity. Enzyme activity of osteoclasts, and metaphyseal and perichondrial osteoblasts was high. Endosteal and periosteal osteoblasts varied in activity depending upon the area under observation. Preosteoblasts (progenitive cells) of the osteogenic periosteum, osteochondrogenic cells of the perichondrial region, chondrocytes, and cells of the fibrous periosteum demonstrated minimal activity. Osteocytes were negative. The distribution of osteoblast APTase activity coincided with areas of active collagen synthesis.
Regional differences in androgenic sensitivity of the chick comb and effects related to volume of inuncted vehicle
Authors: Wollman Arthur L. , Hamilton James B.
Published: February 2005

Combs of chicks were divided surgically into posterior (P‐comb) and anterior (A‐comb) portions of equal weight, thus providing two separate target organs in the same animal. Inunction with testosterone propionate stimulated equal increments in P‐ and A‐combs with regard to values for length + height, but weight of the P‐comb increased significantly more than that of the A‐comb as a result of greater increase in width of the P‐ than of the A‐comb. The P‐ was five times more responsive than the A‐comb and contained larger amounts of ground substance as shown by histological examination and larger amounts of hexosamine as shown by chemical study. It was concluded that these two portions of the comb differed greatly in capacity to grow in response to androgenic stimulation.

Reduction in the volume of the vehicle from 5 to 0.5 μl resulted in a sevenfold greater response of the chick comb to androgens.

Restriction in the volume of vehicle and the use of the P‐comb alone did not alter the precision of assay. Use of these procedures would permit measurement of androgens in amounts hitherto too small for assay.
The effects of prolonged low level radiation on the Coronary vessels of the developing chick embryo
Authors: Davis J. E.
Published: February 2005

Microcurie amounts of p32, Na22, Fe59, and Cl36 in normally occurring compounds were injected directly into the vitelline vessels of developing chick embryos at stage 24 (Hamburger and Hamilton, '51). The surviving embryos were sacrificed at stage 41. Hearts were removed and examined intact or sectioned for later examination. Coronary vessels were identified, classified according to size (large, diameter = > 80 μ; medium, diameter = 40–80 μ; small, diameter < 40 μ) and counted. There was a significant increase in the numbers of small and medium vessels which had developed in the presence of gamma radiation emitted by Na22‐ and Fe59‐compounds. The p32‐ and Cl36‐containing compounds did not affect the numbers of vessels of any size. The resulting increased vascularity is shown to be a matter of a distinct increase in numbers of blood vessels as opposed to a simple alteration of the normally occurring vessels.
The architecture of the thyroid gland: A 3‐dimensional investigation
Authors: Isler H. , Sarkar S. K. , Thompson B. , Tonkin R.
Published: February 2005

The three‐dimensional structure of the thyroid gland was investigated by reconstructing three‐dimensional models from serial sections of the rat thyroid, stained with the periodic acid‐Schiff technique to identify the basement membrane. It was found that the follicles were not completely separated from each other by connective tissue, reticular fibers, or basement membranes. At some points, the base of the epithelium of a follicle was in direct contact with the base of the epithelium of an adjacent follicle. An area of contact involved about a dozen follicular cells in each follicle. One follicle usually had two or more areas of epithelial contact. All follicles examined in three dimensions (over 100), showed epithelial contacts, in one‐year‐old as well as in younger rats. The area of contact between parenchyma and stroma, as marked by the basement membrane, consisted of a branching system of anastomosed and partially pinched sacs, within which the epithelia of the follicles were in direct contact. Thus, each follicle can no longer be considered as being completely surrounded by connective tissue or even wrapped by a basement membrane discrete from those of neighbour follicles, and therefore its individuality is essentially due to the fact that it owns a discrete lumen.
Fibrillovesicular cells in the Fundic glands of the canine stomach: Evidence for a new cell type
Authors: Hammond James B. , Ladeur Linda
Published: February 2005

Biopsies of the gastric fundal mucosa were obtained from 25 dogs and processed for light and electron microscopy. A cell distinguishable from superficial mucous, mucous neck, chief, parietal, or argentaffin cells was observed.

By light microscopy in resin‐embedded, methylene‐blue‐stained sections, this cell was noted to have a prominent apical region which protruded into the gland lumen, a conspicuous terminal web traversed by parallel fibrils, and a crescent‐shaped nucleus; secretory granules were absent.

By electron microscopy this cell had the following features: (1) short, stubby microvilli with well developed terminal web, (2) fibril‐bundles constituting the cores of microvilli and extending through the apical cytoplasm to the paranuclear region, (3) characteristic vesicles and tubular structures in the apical cytoplasm, (4) spiral structures, and (5) oval dense bodies.

Morphological evidence supported the hypothesis that this is a distinct cell type; it is referred to as a fibrillovesicular (FV) cell.
Linear growth and appearance of sex difference in the rabbit pelvis
Authors: Lowrance E. W.
Published: February 2005

Roentgenograms of the pelves of a population of rabbits were secured once each week between 15 and 92 days after birth and once every two weeks thereafter to 204 days. Measurements were made of projections of certain pelvic dimensions on the roentgenograms.

With one exception (pelvis width, day 36), no significant differences at the 1% level between males and females were found in os coxae length, ilium length, pelvis width and bi‐ischial width. However, interacetabular width of the female became significantly greater than that of the male by day 57.

Mean measurements of all dimensions showed characteristic rates of increase with age. Nine‐tenths of total increase in lengths of os coxae and ilium occurred by 106 days; pelvis width, by 120 days; bi‐ischial and interacetabular width each, by about 148 days.

Between 35 mm to 105 mm of tibia length taken as a basis of reference, all dimensions studied showed approximately straight line relative growth trends.

Variation in measurements was relatively high, with greatest variation in all except bi‐ischial width tending to occur before 50 days, when growth was most rapid. It was lowest in the period 64 to 120 days.
Studies on the experimental induction of overgrowth in chick embryos
Authors: Burda Doris J.
Published: February 2005

An analysis has been made of the experimental conditions under which overgrowth can be produced in the brains of chick embryos. A total of 122 individuals were obtained from six series of embryos subjected to varying degrees of surgical manipulation involving the anterior rhombomere and/or its substratum. The results indicate that in addition to the cases of overgrowth obtained by the standard technique of removing the entire anterior rhombomere, overgrowth could also be successfully induced when a portion of the chordamesoderm underlying the anterior rhombomere was either removed or merely dissociated from the neural tissue, while leaving the latter relatively intact. In embryos in which the roof and sides of the anterior rhombomere were removed, overgrowth could not be obtained in the absence of damage to the substratum.
Annulated lamellae in the ductus epididymidis of fetal and castrated adult rats
Authors: Van De Velde Robert L. , Van De Velde Sharon C.
Published: February 2005

A consistent feature of epithelial cells lining the initial segment of the ductus epididymidis of rats bilaterally castrated for about three months is the presence of stacks of annulated lamellae. They were occasionally observed by two months following gonadectomy but were not evident in one‐month castrates nor in normal controls or unilaterally orchiectomized rats.

Observation of epididymides from neonatal and fetal rats taken at daily intervals between the twelfth and twenty‐first day following conception demonstrated that small and inconspicuous annulated lamellae occurred normally during differentiation. They were observed on several occasions in widely scattered cells during the fifteenth day of gestation.

In the epididymis, annulated membranes may form from the outer nuclear membrane by a process of budding. The annulated membrane complex is “destroyed” in long term castrates following the subcutaneous injection of testosterone proprionate.
Capillary endothelial fenestrations in the lamina propria of the guinea pig tongue
Authors: Takada Mitsuya , Gore Ira
Published: February 2005

Fenestrations of the capillary endothelium have been observed in the lamina propria of the guinea pig tongue. They measure about 600 Å in diameter and are closed by a diaphragm. The diaphragm is thinner and less electron‐dense than the endothelial cell plasma membrane, and occasionally displays a central thickening, “knob” or “a dense ring‐like structure.” Similar fenestrations are sometimes observed in the walls of endothelial vesicles as well.
Phosphotungstic acid staining of the organ of corti for electron microscopy
Authors: Nakai Yoshiaki , Hilding David A.
Published: February 2005

Phosphotungstic acid (PTA) 1% in absolute alcohol was used, according to Bloom and Aghajanian's ('66) method, during the final dehydration stage of glutaraldehyde‐fixed cochlear specimens which were processed for electron microscopic study without osmium treatment. Familiar structures emerged with additional characteristics. PTA stained supporting elements. Synaptic areas were emphasized and the synaptic bar of hair cells opposite afferent endings was densely stained. Dark clumps were found near the synaptic surface of efferent nerve endings that seemed to correspond to the material sometimes seen between vesicles near the synaptic cleft. A dense layer was present in hair cells opposite efferent terminals between the outer layer of the double membrane and the synaptic membrane. Formations resembling synapses between the nerve endings of outer hair cells were emphasized by PTA staining, but were difficult to find because of their rarity. It seems unlikely that synaptic interaction between cochlear nerve endings is vital in the basic physiology of hearing.

PTA staining permits recognition of cochlear nerve ending type independent of hair cell features which will make it a useful aid for the study of the development of the inner ear and of pathological ear conditions.
A relationship between ovarian and genital tract eosinophilic granulated cells
Authors: Brown Joan E. , Nellor J. E.
Published: February 2005

Estrogen secretion by the ovary, as estimated by changes in genital tract tissues, can be directly correlated with the appearance of eosinophilic granulated cells within the ovarian tissues. Ovarian eosinophilia and development of the genital tract of the gilt are prominent from the eleventh to fifteenth days of the estrous cycle, between the twenty‐fourth and forty‐fourth, and after the eighty‐sixth days of pregnancy. It is suggested that the appearance of eosinophilic granulated cells in ovarian tissues is a direct effect of ovarian estrogens, as is the appearance of genital tract eosinophilic granulated cells subsequent to estrogen release from the ovaries. The appearance of eosinophilic granulated cells in ovarian tissues provides a means whereby the portion of the ovary involved in estrogen secretion can be identified. Eosinophilic granulated cells were observed in thecal layers of secondary, tertiary and atretic follicles and in the connective tissues surrounding and penetrating recently formed corpora lutea. Ovarian eosinophilic granulated cells are not of immediate blood origin, but arise from undifferentiated mesenchymal cells. In the process of accumulation of eosinophilic granules and modification of nuclear chromatin to bi‐ or multinucleated forms, cellular death occurs and the granules and chromatin particles are released in the tissues.
Effects of gonadectomy and hypophysectomy on the pineal body in the mouse: A quantitative morphological study
Authors: Ito Takashi , Matsushima Shoji
Published: February 2005

A quantitative morphological study was made to assess the effects of gonadectomy and hypophysectomy on the pineal in the mouse. Gonadectomy caused a slight increase in the pineal volume whereas hypophysectomy induced a marked decrease. The increase in pineal volume after gonadectomy was associated primarily with slight enlargement of pineal cells in the peripheral area of the gland, and the larger decrease in pineal volume after hypophysectomy correlated with marked atrophy of pineal cells throughout the entire gland.
Nerve cells in the extracranial portion of the hypoglossal nerve in human fetuses
Authors: Woźniak Witold , Young Paul A.
Published: February 2005

The hypoglossal nerve with its communicating branches between the hypoglossal canal and its terminal rami was removed in toto from 11 human fetuses varying from 63 to 342 mm C.R. length. Serial sections were stained with luxol fast blue or impregnated with silver nitrate or protargol according to Bodian's method. The total number of nerve cells varied from 10 to 82 on the right side and from 6 to 60 on the left. Morphologically these cells resembled the cells in the inferior ganglion of the vagus nerve and they were always observed within the communicating rami between this ganglion and the hypoglossal nerve. The possibility of migration of these cells from the inferior ganglion of the vagus to the hypoglossal nerve and their relationship to the proprioceptive innervation of the tongue are discussed.
Histochemical observation on phosphatase activities of degenerating and regenerating taste buds
Authors: Iwayama Takashi , Nada Osami
Published: February 2005

Using rat's circumvallate papillae, ATPase, alk. Pase and acid Pase of taste buds were observed after the transection of the glossopharyngeal nerve.

The taste buds began to disappear after the nerve was cut and were completely lost after ten days. Following the regeneration of the glossopharyngeal nerve, taste buds reappeared from the bottom of the gutters of circumvallate papillae about 25 days after the operation.

ATPase was strongly present on the cell membrane of taste bud cells as far as they existed during degeneration and regeneration. Alk. Pase, which is normally localized on the superficial layers of the epithelium overlying the gutters of circumvallate papilla, gradually diminished as the taste buds degenerated and reappeared as the taste buds regenerated; that is, the activity began to diminish three days after the operation, became feeble after ten days and reappeared after 25 days. It is concluded that taste bud cells secrete alk. Pase in the gutters of circumvallate papillae. Acid Pase activity, usually found in the supranuclear portion of taste bud cells, was intensely reactive during degeneration but did not reappear at the early stage of regeneration of taste bud cells.