bluuebunny/crossref_metadata_2025_split huggingface dataset:
Expansion of placental site and maternal blood supply of primate placentas
Authors: Gruenwald Peter 
Published: February 2005

AbstractDevelopment of placental site and uteroplacental arteries was studied in Tarsiidae, Ceboidea, Cercopithecoidea, and Hominoidea. In Tarsiidae the placental attachment and single artery remain essentially unchanged from early on, and the placenta grows beyond the original site in the shape of a button. In Tarsiidae and Ceboidea maternal arteries and their branches are incorporated in the placenta and their wall is replaced later by a layer of fibrin, Ceboidea have several arteries in the original placental site; this site is enlarged including additional arteries by ingrowth of villi from the chorion in an area surrounding the original site. Further growth is by centrifugal spread; the basal endometrium is stretched and no new arteries are tapped. In Cercopithecoidea the placenta has a sharp border from early on. Spread with stretching of the underlying endometrium occurs here, too. Additional arteries running in this stretched endometrium are secondarily tapped and increase the total number. The disc of Hominoidea, remaining after formation of the chorion laeve, also stretches the underlying decidua, but then trophoblast pervades much of it until it taps arteries in a much larger area than in the other forms.
Effects of estrogen on the transition zone of the mouse uterine cervix
Authors: Bradley Carolyn F. , Graham Charles E. 
Published: February 2005

AbstractHistologic changes in the region of the squamocolumnar junction of the uterine cervix in ovariectomized C3H/HeJ mice were studied at 6‐12 hour intervals after the injection of 2.3μg estradiol benzoate. Mitotic activity, especially in the basal layer of stratified squamous epithelium, increased as time elapsed after estrogen administration and produced a concomitant increase in stratification of squamous epithelium; some mitotic activity was present in the uterine columnar epithelium throughout the period of observation. The histologic character of the squamocolumnar junction changed from gradual transition to an abrupt demarcation, as in intact mice during the estrous cycle. Subcolumnar cells in the transition zone of untreated animals formed a unilayered reticulum which after estrogen injection developed into a reticulum of stratified squamous epithelium. Extensions of stratified epithelium which develop during chronic estrogen treatment apparently develop from the stratified reticulum. There was no evidence to indicate any contribution of metaplasia to estrogen‐induced epidermization.
Differences in histochemical attributes between diaphragm and hindleg muscles of the rat
Authors: Yellin Herbert 
Published: February 2005

AbstractMuscle fibers of the diaphragm and hindleg muscles of the rat were characterized bistochemically by their mitochondrial distribution (succinic dehydrogenase activity) as A, B and C (after Stein and Padykula, '62), by their myofibrillar, alkali‐stabile ATPase activity as α, β and αβ (after Samaha et al., '70), and by their acid‐stabile ATPases (intermyofibrillar and myofibrillar) as D (dark), M (moderate) and L (light). Comparisons of the differentially stained serial sections revealed profound dissimilarities between the fibers of functionally disparate muscles. The majority of fibers of the hindleg muscles were distinguishable as the conjugates AαβM, BβTD and CαL (figs. 1‐3), whereas those of the diaphragm were principally AαM, BαL and CβD (figs. 4‐6). Thus, no one histochemical reaction could accurately predict the multiple attributes of fibers of both muscle groups. Previous studies suggest that additional discrepancies in histochemical appearance would arise were other specialized muscles, e.g., extraocular muscles (Yellin, '69), compared with the more common muscles of body and limb. Any extrapolation of data on the basis of limited histochemical analyses is not without risk, whether comparing the same muscle in different species (Yellin and Guth, '70), or different muscles in the same species.
Proprioceptive afferents in facial nerves of some insectivores
Authors: Kubota Kinziro , Masegi Toshiaki 
Published: February 2005

AbstractFiber‐caliber analysis of the facial nerve was made in the Japanese lesser shrew‐mole and the Japanese shrew‐mole possessing muscle spindles in the snout muscles and in the shinto shrew with no spindles. Using an enlarged photographic scale (× 250) prepared from the object‐micrometer (1/100 mm), the measurement of the fiber‐caliber was made on the enlarged photograph (× 1250) of the cross paraffin section treated with a modified myelin‐sheath staining procedure by Pettersen et al. ('70). The facial nerves of the shrew‐moles contained fibres of 1 to 10 μ in diameter, while the facial nerve of the shrew consisted of fibers of 1 to 6 μ The spectra of the former have a slight bimodality with the highest peak at 2 μ and smaller one at 6 μ. The spectrum of the latter has a unimodality with a greater peak at 2 μ. Each peak revealed a log‐normal distribution curve. Statistically, it can be said that there is a significant difference in the caliber‐spectra between the facial nerves supplying the snout muscles with muscle spindles and without spindles.For testing whether the skew of the spectrum can be the result of a truly bi‐modal distribution, the left facial nerve of the Japanese shrew‐moles was cut at the site beneath the auditory capsule. Complete degeneration of spindle innervation in the snout muscles was observed histologically in animals seven days after operation.
Estrogen‐induced osteoid formation in the osteon of mature female rabbits. An electron‐microscopic study
Authors: Whitsan S. William 
Published: February 2005

AbstractThe osteons of mature female rabbits injected with estradiol valerate, parathyroid extract, or a combination of both were studied. Two, 1 mg injections of estradiol valerate (Delestrogen®) given in a one week period stimulated osteoid production on the inside of the lacunar borders of osteocytes but had little effect on osteoid production along the perimeter of the Haversian canal. Parathyroid hormone induced osteolysis after two weeks of treatments, with little apparent increase in osteoclast numbers. Parathyroid extract treatment for one week followed by estradiol valerate treatment in combination with parathyroid extract treatment the second week induced osteoid formation along both lacunar borders and Haversian canal perimeters. This evidence shows that estrogen can stimulate osteoid production and is not limited to inhibition of bone resorption. Increased osteoid production along the perimeter of the Haversian canal in dual‐treated rabbits implies an interaction between estrogen and parathyroid hormone.
Acid phosphatase distribution in the trigeminal ganglion of the rat
Authors: Peach Roy 
Published: February 2005

AbstractLocalization of acid phosphatase in trigeminal ganglia of vascularly perfused, young, Wistar rats was demonstrated by Gomori's lead sulfide and Barka and Anderson's azo dye methods. Differences in deposition of reaction product, indicating differences in levels of enzyme activity, were demonstrated between small, intensely reactive (dark) neurons and larger, less reactive (light) neurons. Lengthening the fixation time to lessen the likelihood of artifactual origin of such differences resulted in a decreased reaction in all neurons; relative difference in intensity of large and small neurons was retained. The results indicate that the level of detectable acid phosphatase activity is an additional distinguishing feature between light and dark cells in trigeminal ganglia of the rat and suggest that differences between these cells are not artifactual.
Total leydig cell volume and its estimation in dogs and in models of testis
Authors: Kothari L. K. , Srivastava D. K. , Mishra Pushpa , Patni M. K. 
Published: February 2005

AbstractThe total Leydig cell volume has been determined in 40 dog testes using a histometric point‐counting method. In preliminary experiments, the accuracy of the method has been established on specially prepared plasticine models of the testis. The point‐counting method has a mean error of ± 7% and the values obtained by it, when statistically analysed, are not significantly different from those determined by direct measurements (p > 10% ). Thus, work on the models has provided convincing experimental verification of the method.The Leydig cells constitute about 15% (14.2 to 17.1% ) of the testicular volume in dogs. In absolute terms, it comes out to be 1.56 ± 0.45 ml of Leydig cells per testis. Larger testes contain proportionally greater amount of Leydig cell tissue, the relationship being almost linear. Although very little data is available for comparison, and none perhaps for the dog, it appears from the present study that the total quantity of Leydig cells in this species is essentially the same as in man.Since it allows a reliable estimate of the total Leydig cell volume directly in milliliters per testis, the point‐counting method has proved to be much more useful than older methods which merely determined the proportion of Leydig cells in relation to some other testicular component.
Ultrastructure of the rat testis after vasectomy
Authors: Flickinger Charles J. 
Published: February 2005

AbstractThe fine structure of the rat testis was studied at intervals of up to nine months after bilateral vasectomy, unilateral vasectomy, or a bilateral sham operation. Objectives were to determine whether the fine structure of the testis is altered as a result of vasectomy and to determine if any of the sperm produced after vasectomy are retained and disposed of within the testis. Attention was directed toward the ultrastructure of developing spermatids, the cytology of Sertoli cells, and the structural relationships between Sertoli cells and germ cells. No alterations in these features were detected, and it was concluded that the fine structure of the rat testis remains normal after vasectomy. Factors are discussed which may qualify this conclusion, such as the structural complexity of developing germ cells and the multiplicity of stages in the cycle of the seminiferous epithelium. Sertoli cells contained residual bodies after vasectomy, but there was no evidence that phagocytosis by Sertoli cells increased, suggesting that the main site of disposal of sperm after vasectomy lies distal to the seminiferous tubules.
Protein uptake by rat preimplantation stages
Authors: Schlafke Sandra , Enders Allen C. 
Published: February 2005

AbstractThe protein tracers, horseradish peroxidase and ferritin, are demonstrable in the subzonal space of all preimplantation stages within ten minutes when incubated in vivo or in vitro. However, there is very little uptake of these proteins by ova and two‐cell stages. By the blastocyst stage there is greatly increased uptake of exogenous protein. The proteins appear in coated micropinocytotic vesicles and tubules, larger vacuoles, and more complex bodies. Blastocysts from the period of lactationally delayed implantation show an even greater amount of uptake, especially in the supranuclear region. Peroxidase reaction product can be demonstrated in the cavity of day 5 blastocysts in 30 minutes, and in the cavity and basal lamina of the blastocysts during delayed implantation in ten minutes. Ferritin was more sparsely distributed, and was not seen in the blastocyst cavity in any of the time periods. Peroxidase is apparently transported via an intracellular pathway, since it is not seen in the elaborate intercellular spaces between trophoblast cells. Acid phosphatase activity is demonstrable in vacuoles, dense bodies and Golgi cisternae in all stages, indicating that the potential for degradation of ooplasm and phagocytized material by a lysosomal system is present in all of the preimplantation stages examined.
Ultrastructure and growth of human limb mesenchyme (HLM15) in vitro
Authors: Kelley Robert O. , Baker Thomas I. , Crissman Harry A. , Henderson Carolyn A. 
Published: February 2005

AbstractHuman embryonic hand and foot plates (horizon XVI) exhibit localized differences in mitotic activity between developing digital and interdigital zones of mesenchyme. To investigate development of regulation of cell reproduction, mesenchymal cells from lower limb buds dissected from a human embryo (stage XV) were cultured. Electron microscopy reveals that HLM15 cells in situ are fibroblastic, exhibit euchromatic nuclei, one to two peripheral nucleoli, extensive granular ER, free ribosomes, and microfilaments and microtubules oriented in the long axis of cellular processes. Cells released from substratum with trypsin‐EDTA become rounded and microfilaments and microtubules become disoriented, perinuclear bundles. HLM15 has a mean generation time of 24 hours during logarithmic growth and karyotype analysis indicates that cells retain diploid chromosomal number after 17 passages. DNA‐fluorochrome analysis on the Los Alamos Flow Microfluorometer (FMF) demonstrates that HLM15 cells possess no detectable polyploidy. Computer fit of FMF distributions reveal that random populations of HLM15 during exponential growth contain 42.6% cells in G1, 45.9% in S and 11.5% in G2+M. As confluency is reached these data become 57.6%, 37.5% and 4.9% respectively. Disaggregated limb mesenchyme (in vivo) analyzed without culturing exhibit FMF distributions of 56.1% in G1, 36.7% in S and 7.2% in G2+M. Similarities in cell cycles between near‐confluent HLM15 cultures and limb mesenchyme in vivo suggest that regulation can be achieved by increasing or decreasing the traverse time through G1 (both in vitro and in vivo). The proportion of non‐cycling cells (G0) in the FMF G1 distribution is presently not known.
The migration of lymphocytes from bone marrow to popliteal lymph nodes demonstrated by selective bone marrow labeling with 3H‐thymidine in vivo
Authors: Brahim F. , Osmond D. G. 
Published: February 2005

AbstractGuinea pig popliteal lymph nodes were examined by DNA radioassay and radioautography following the selective labeling of tibial and femoral marrow cells by intramyeloid injections of 3H‐thymidine. The DNA radioactivity of the node increased for the first four days and at four to seven days exceeded that seen after an intraperitoneal injection of the same total dose of 3H‐thymidine, indicating an export of radioactivity from the labeled marrow to the node. Simultaneously, radioautographic sections of the node revealed labeled cells indicative of an origin from marrow precursors. Small lymphocytes constituted 60–90% of the labeled cells and reached maximal numbers at four to six days. Most of them were observed in the cortex, including the subcapsular sinus, primary follicles, mantle zones around germinal centers, and the lumen and walls of post‐capillary venules. However, the highest labeling indices of small lymphocytes occurred in the medulla, including the medullary cords, medullary sinuses and efferent lymphatic vessels. Labeled large mononuclear cells, including large lymphoid cells, monocytes and large blast cells, were confined almost exclusively to the cortex. A small number of labeled plasma cells was observed in the medullary cords. It is concluded that newly‐formed bone marrow lymphocytes migrate continuously into immunologically quiescent lymph nodes and become widely distributed throughout the cortex and medulla, while some enter the recirculating small lymphocyte pool.
Distribution of thyroid, parathyroid, and ultimobranchial hypocalcemic factors in birds. II. Morphology, Histochemistry, and hypocalcemic activity of pigeon thyroid glands
Authors: Hoyt Richard F. , Hamilton David W. , Tashjian Armen H. 
Published: February 2005

AbstractThyroid lobes from five common and six White Carneaux pigeons were cut into fragments which were assayed biologically for their calcitonin content. Pooled, alternate tissue slices from the individual thyroid lobes of 18 additional White Carneaux pigeons were assayed; the remaining tissue slices were prepared for light and electron microscopy or for demonstration of histochemical properties associated with the APUD system of polypeptide hormone‐producing cells, including: α‐glycerophosphate dehydrogenase, acetylcholinesterase, nonspecific cholinesterase, esterase, argyrophilia, and production of fluorogenic monoamines. Calcitonin was present at all cephalo‐caudal levels within pigeon thyroid lobes and was concentrated in peripheral, as opposed to central areas of the lobes. White Carneaux left thyroid lobes contained 34–225 MRC U of calcitonin/g tissue. Twelve of 18 right lobes lacked detectable calcitonin; the remaining six lobes contained 12–46 MRC U/g. Microscopy revealed a population of granulated cells that were found only in peripheral regions of lobes containing measurable calcitonin. These cells resemble mammalian thyroid parafollicular cells ultrastructurally. They appear to be surrounded by amine‐containing, argyrophilic nerve fibers. Of the histochemical characteristics of mammalian “C” cells tested, only amine‐precursor uptake could be correlated with the presence of calcitonin and granulated cells in the thyroid gland of the White Carneaux pigeon.
Electromyography of the human cheeks and lips
Authors: Isley Charles L. , Basmajian John V. 
Published: February 2005

AbstractTo clear up indecision and disparities in the literature of muscular functions in the cheek and lips, multichannel electromyography with fine‐wire intramuscular electrodes was used in eight subjects. Both facial expressions and musical performance were investigated. Intersubject variations were common in the various muscles and intrasubject variation also appeared. The production of specific notes at specific volume on the trumpet or trombone did not depend on exact patterns of activity in the muscles of the lips and buccinator. Gentle puffing out of the cheek produces little or no activity in any muscle, but when this is done forcefully the orbicularis oris activity is marked. Buccinator can be kept deliberately relaxed or active during puffing. Smiling always produces buccinator activity as does forceful retraction of the corners of the mouth. Levator anguli oris activity always recruits concurrent buccinator activity but the reverse is not true.
Fine structure of acinar cells of human parotid gland
Authors: Riva Alessandro , Riva ‐Testa Francesca 
Published: February 2005

AbstractAcini of human parotid gland consist of pyramidal secretory cells and of flattened, basally placed, myoepithelial cells.Since secretory cells show a cytological organization intermediate between that of exocrine pancreas and that of mucous glands, human parotid is considered to be a seromucous gland. Short intercellular canaliculi extend between apical portions of secretory cells; more basally intercellular spaces, constantly separated from the lumen, are seen. Variations observed in cytology of secretory cells are believed to be more likely related to the presence of stages of a maturative cycle rather than to the existence of different types of cells. Secretory granules often show a bipartite structure consisting of a main portion and of a dense body (or core) contained in it. On the basis of the appearance of the main portion, dark and pale granules are recognizable. Dark granules are quite dense and homogeneous while pale granules, which tend to coalesce, are formed by a clear flocculent material. Together with granules endowed with intermediate characters, dark and pale granules are often present even in the same cell. Discharge of secretion into the lumen seems to take place following the fusion of the membrane of the secretory granule with the plasmalemma. In fact, bulging secretory granules and subluminal clefts are frequently seen. The shape of nuclei and the pattern of their chromatin content vary apparently with the cell cycle. Inside the nuclei, a distinct fibrous lamina, nucleoli and nuclear bodies are present. In addition, some nuclei exhibit a laminated inclusion arranged concentrically.Myoepithelial cells have an elongated body and thin processes extending among secretory cells. They are characterized by a filamentous cytoplasm poor in organelles.
The stomach gland patch of the koala (Phascolarctos cinereus)
Authors: Krause William J. , Leeson C. Roland 
Published: February 2005

AbstractA large gland patch is found in the submucosa of the lesser curvature of the koala stomach near the entrance of the esophagus. It measures approximately 3 cm in diameter and is comprised of numerous invaginations continuous with the surrounding mucosa. The glandular invaginations drain into the lumen of the stomach by 25 to 30 large orifices. The mucosa of the gland patch invaginations differs from the mucosal lining of the stomach chiefly in thickness. The elongate gastric glands that comprise the invaginations exhibit an increased number of parietal and chief cells. Ultrastructural examination of the gland patch illustrates that the parietal, chief, and mucous neck cells are similar in structure to those of other mammalian species.
Inferior rectal nerve variations as it relates to pudendal block
Authors: Roberts Walter H. B. , Taylor William Holmes 
Published: February 2005

AbstractThe fact that the inferior rectal nerve may have an independent origin from the sacral plexus is acknowledged in most current anatomy texts. That it may pierce the sacrospinous ligament well medial to the ischial spine is no longer mentioned. This variation which may occur in as many as 20% of the sides examined, could present a problem in pudendal block.
Maturation of goblet cells of the mouse small intestine as shown by the uptake of 35S‐sodium sulfate
Authors: Merzel José , Almeida Maria Lúcia P. 
Published: February 2005

AbstractAdult male mice fed “ad libitum” were given a single intraperitoneal injection of 35S‐sodium sulfate and sacrificed one, three and six hours after. Plastic embedded one micron thick sections from duodenum, jejunum and ileum were radioautographed and the uptake of the 35S by goblet cells was analysed. Goblet cells of the small intestine originate in crypts and migrate to villi reaching their tips where they are released into the intestinal lumen. Radioautographic reaction appeared over all goblet cells whether in the crypts or in the villi indicating continual synthesis of sulfomucins.By determining the silver grain concentration over goblet cells at different levels of crypts and villi it was shown that the cells of duodenum and jejunum become more active in the synthesis of sulfomucin, when they reach the upper half of the villi. In the ileum, although a similar maturation may occur, the results were not statistically significant.
Fine structure of the urinary bladder of the bullfrog, (Rana catesbiana)
Authors: Strum Judy M. , Danon David 
Published: February 2005

AbstractThe urinary bladder of the bullfrog, Rana catesbiana has been studied by light and electron microscopy. Three epithelial cell types were found: (1) granular cells, (2) mitochondria‐rich cells, and (3) basal cells. The structure of the Rana catesbiana bladder differs from that of the toad Bufo marinus, in several respects: it lacks a mucous (goblet) cell type, its granular cells do not contact the underlying basement membrane, it has specialized, smooth‐muscle cell‐basal epithelial cell contacts, not previously described in amphibian bladders, and its mucosa is richly innervated. Mitochondria‐rich cells within the bullfrog bladder epithelium were occasionally observed touching the basement membrane. The specialized smooth muscle‐basal cell contacts provide anatomical evidence for how regulatory vasoactive substances such as neurohypophyseal peptides might alter epithelial geometry. Many nerve endings invest the mucosa just beneath the epithelial basement membrane in proximity to mitochondriarich cells and basal cells. The possible role of neural regulation in epithelial transport was discussed.