bluuebunny/crossref_metadata_2025_split huggingface dataset:
The effects of temperature on gustatory response of rats
Authors: Yamashita Satoru , Sato Masayasu 
Published: February 2005

AbstractImpulse discharges in the chorda tympani nerve of rats to stimulation of the tongue by NaCl, KCl, CaCl2, HCl, quinine and sucrose at varying temperatures were recorded using an integrator. The tongue had been preadapted to temperature of stimulating solutions so as to eliminate thermal response. The magnitude of response to all kinds of stimuli except for sodium salts of 0.01 to 0.03 M was increased with a rise in temperature from 10° to 30°C and declined from 30° to 45°C, indicating the greatest magnitude at about 30°C. The response magnitude for 0.01 M NaCl was decreased with a rise in temperature from 10° to 45°C. The threshold for NaCl rises with a rise in temperature. Q10 values for the magnitude of response to 0.03 M to 1.0 M NaCl, KCl, CaCl2, HCl, quinine and sucrose are less than two between 10° and 30°C, −1.1 to −1.9 between 30° to 40°C and −1.8 to −3.4 between 35° and 45°C. Sucrose, HCl and quinine gave greater Q10 values than did NaCl, KCl and CaCl2. From such small Q10 values it has been concluded that the reaction between taste receptors and stimuli, which ultimately leads to initiation of gustatory impulses, is of physical nature rather than enzymatic one.
Studies on sympathetic B and C neurons and patterns of preganglionic innervation
Authors: Nishi S. , Soeda H. , Koketsu K. 
Published: February 2005

AbstractThe sympathetic ganglion of the toad consists of two kinds of neurons, the sB and sC neurons of which axons are the B and C fibers, respectively. The sB neurons receive a monosegmental innervation of preganglionic B fibers whereas the sC neurons receive mono‐ or multisegmental innervation of preganglionic C fibers. The pre‐ and postganglionic neurons are divided into a fast (sB neuron) and slow (sC neuron) conduction system. The conduction velocity of the preganglionic axons is proportional to that of the synaptically connected postganglionic neuron axons in the sB and sC neuron systems. In the sB neuron system, the conduction velocity of the preganglionic axons is faster than that of the postganglionic fibers. The relation is reversed in the sC neuron system. The antidromic and orthodromic responses as well as the electrical membrane properties of sC neurons were analyzed and compared with those of the sB neurons. In both neurons, the time constant of the synaptic potential decay was always longer than that of the membrane. The synaptic potentials of sB and sC neurons were abolished at the membrane potential levels of −10 mv and −7 mv on the average, respectively, which indicates that the equilibrium potentials of these neurons are almost the same. The changes in the excitability of the soma as well as axon of the sB and sC neurons after a single response and the response of the sB and sC neurons to a long cathodal current were analyzed and compared.
The attachment of glycolytic enzymes to muscle ultrastructure
Authors: Amberson William R. , Roisen Fred J. , Bauer Adelia C. 
Published: February 2005

AbstractThe glycolytic enzymes, lactic dehydrogenase and aldolase, usually thought to be freely dissolved in the sarcoplasmic matrix, are in good part attached to the muscle ultrastructure. This attachment becomes manifest when the enzyme activities and specific activities of the press juices of whole skeletal muscles (rabbit) are compared with those of minced muscles, all obtained by ultracentrifugation of the tissues at 40,000 xpm for 16 to 20 hours. Mincing causes a great increase in the activities, associated with a rise in the volume and protein concentration of the press juices. We interpret these increases to be due to the solution in the matrix of enzymes previously attached to the ultrastructure.The same conclusion is reached by a different method, which we call “washing the ultrastructure.” It consists in multiple centrifugations of whole skeletal muscles, and removal of press juices, alternating with periods of imbibition of a buffer (0.1 M phosphate at pH 7.5) too dilute to dissolve out the fibrous proteins. During the imbibitions enzymes diffuse out into the buffer not imbibed, which becomes an extract. After four centrifugation‐imbibition sequences in as many days nearly all of the fluid matrix has been replaced by buffer. Enzyme activities fall steeply in press juices and extracts until nearly all freely dissolved enzymes have been washed away. Homogenates of the pressed muscles then show activities which are about half of those found in the homogenates of unpressed control muscles. We conclude that the enzymes found in the homogenates of the pressed muscles have previously been attached to the ultrastructure.Similar experiments with heart muscle indicate that nearly all of these enzymes are normally attached to the ultrastructure. Press juices contain only traces of activity, even after the heart has been minced. A fraction of the enzymes is slowly detached during the centrifugation‐imbibition sequences, appearing mainly in the extracts.
The effect of carcinogenic hydrocarbons on rodent and primate cells in vitro
Authors: Diamond Leila 
Published: February 2005

AbstractThe effect of polycyclic hydrocarbons on rodent and primate cells in vitro was studied using dimethyl sulfoxide as the initial solvent for the hydrocarbons prior to their addition to the cell cultures. Because the dimethyl sulfoxide was not toxic to the cells at a final concentration in which relatively high concentrations of the hydrocarbons remained in solution in the medium, the effects of the compounds could be measured quantitatively.The carcinogenic hydrocarbons, benzpyrene and methylcholanthrene, but not the non‐carcinogenic hydrocarbon, pyrene, inhibited the multiplication of normal embryonic cells from several rodent species. However, concentrations of the carcinogens as high as 10 μg/ml did not affect the growth of virus‐transformed or malignant cells from these species.In contrast to the differential cytotoxic response of normal and malignant rodent cells to the carcinogenic hydrocarbons, the multiplication of normal, as well as transformed, monkey and human cells was not inhibited by benzpyrene or methylcholanthrene at concentrations of 10 to 20 μg/ml. Organ cultures of human embryonic skin initiated and maintained for ten weeks in medium containing 5 μg benzpyrene/ml showed no abnormalities in the growth rate or morphology of the fibroblasts that grew out of the explants.
Penetration of non‐electrolytes through animal integuments
Authors: Buerger A. A. , O'Brien R. D. 
Published: February 2005

AbstractThe rates of penetration were studied of three non‐electrolytes (DDT, Famphur, dimethoate) through the integuments of six animals (Tenebrio molitor, the meal worm adult; Gryllus domesticus, the house cricket; Periplaneta americana, the cockroach; Bufo woodhousei, the garden toad; Anolis carolinensis, the Carolina chameleon; and Phrynsoma cornutum, the Mexican horned toad). The non‐electrolytes were selected with the intention of varying the polarity widely. The olive oil‐water partition coefficients of the above compounds were 199, 19.2 and 0.593. The compounds were applied in 1 μl drops of acetone. In all cases, an initial very brief period of extremely rapid penetration was followed by a long period of much slower penetration. Penetration during the period of rapid penetration was too fast to be resolved by the method used. Penetration during the slower period always followed first order kinetics. During the second slower period, the greater the polarity of a compound, the more rapidly it penetrated into every animal studied but Gryllus domesticus.
The significance of post‐irradiation growth in regenerating limb and tail blastemas of Amblystoma larvae
Authors: Pietsch Paul , Bruce A. K. 
Published: February 2005

AbstractRegenerative growth was studied in limbs and tails exposed to x‐radiation. Significant increases in size were observed following irradiation. Growth eventually ceased in irradiated regenerates and involution set in progressively to claim most of the tissue distal to the amputation plane. This growth was accomplished in spite of severe curtailment of DNA synthesis. On a relative basis the amount of growth was independent of the post‐amputation age of the regenerate at time of exposure to x‐rays. Growth following irradiation showed some dose dependency, but this did not become manifested until after an appreciable time‐lag.It was concluded that at any given moment in the history of the salamander limb or tail there are sufficient numbers of cells capable of forming a blastema without their first having to pass though a phase of high radio‐sensitivity and that these cells are sufficient to account for the aggregation or enlargement of a blastema, independently of normal proliferation.
The effect of efferentiectomy and orchidectomy on the metabolism of the epididymis of the mouse
Authors: Elliott Paul R. 
Published: February 2005

AbstractThe purpose of the study is a comparison of respiratory metabolic rates and anaerobic glycolytic activity (lactate accumulation) in homogenates of epididymides from normal, orchidectomized and testosterone replaced‐orchidectomized mice. Animals subjected to vasa efferentiectomy were used to furnish sperm free homogenates as controls for the homogenates from orchidectomized animals, and to furnish estimates of the contribution of the spermatozoa to these metabolic parameters in homogenates of normal epididymides.Efferentiectomized mice yield homogenates with a significantly lowered rate of respiratory activity (30%). Experiments with fractions of these homogenates showed this reduction in activity to be equivalent to the contribution of the spermatozoa in homogenates from normal mice. No significant difference in the rate of respiratory metabolism was observed among homogenates obtained from efferentiectomized, orchidectomized, testosterone replaced‐orchidectomized, or testosterone injected‐efferentiectomized mice.Efferentiectomy also resulted in a lowered rate of anaerobic glycolytic activity in vitro. No further reduction or elevation of this activity was observed in homogenates from orchidectomized or testosterone injected animals. Further study indicated this loss following efferentiectomy to be due to a reduced glycolytic activity in the epididymal epithelium rather than to the absence of spermatozoan contribution to the metabolism.The evidence presented supports the hypothesis that the presence of some component of the spermatozoa or the fluids in which they reside controls the activation or inhibition of a segment of the lactic dehydrogenase activity which is responsible for the secretion of lactic acid into the epididymal canal for spermatozoan utilization.
Studies on kidney tubulogenesis VI. Survival and nucleic acid metabolism of differentiating mouse metanephrogenic mesenchyme in vitro
Authors: Vainio Tapani , Jainchill John , Clement Keith , Saxén Lauri 
Published: February 2005

AbstractResults obtained from analysis of the early development of embryonic cells under tissue culture conditions apparently reflect both true developmental events and artificial changes consequent upon the isolation and transplantation of the tissues. The magnitude and mechanisms of such changes were examined in a model system, the differentiating metanephrogenic mesenchyme of mouse embryos, which we have used for several analytical studies in developmental biology. The results indicate that isolating and transplanting this tissue to organ culture conditions causes a marked decrease in nucleic acid metabolism, as measured in incorporation experiments. This lag period extends through the first 20 to 30 hours of in vitro cultivation, after which normal metabolism is restored. The change does not seem to be related to cell loss, since viability counts reveal only a small percentage of cells to be dying during this period. Adding Zn++ ions to the culture medium had a favorable effect on the incorporation of nucleic acid precursors during the lag period, suggesting that the enzyme treatment employed during isolation might have removed bivalent cations from this tissue.
Rhabdom structure and receptor potentials in single crayfish retinular cells
Authors: Eguchi Eisuke 
Published: February 2005

AbstractThe effects of continuous darkness and abnormal ionic ratios (excess Ca+ +, Mg+ +, K+, and absence of Na+) on the fine structure of the rhabdoms and on the intracellular retinal receptor potentials were studied in crayfish compound eyes. The normal rhabdom has its constituent microvilli regularly arranged in a characteristic cross‐banded pattern. The normal retinular cell response consists of an initial transient peak and a sustained plateau. After the crayfish were kept for three months in the dark, the regular arrangement of rhabdom microvilli was markedly upset, and receptor potentials of retinular cells in the eye consisted only of the slow phase. The initial phase of the intracellular retinal receptor potential is more labile than the sustained phase (plateau) and was easily abolished if the rhabdom was so strongly affected by continuous darkness, excess Ca+ +, and excess K+ that the fine structural arrangements of microtubules were destroyed. Since receptor potentials were recorded from compound eyes in which rhabdoms were deranged and almost all their microvilli torn off from the retinular cells, transmission of visual excitation from rhabdom to retinular cell soma must be possible without direct membranous connection between them.
Conjugation of paramecium multimicronucleata, powers and mitchell
Authors: Landis Eugene M. 
Published: February 2005

AbstractMicroscopic examination of both living and stained forms indicates that the so‐called ‘multivacuolate’ and ‘amicronucleate races of Paramecium caudatum’ belong to the species Paramecium multimicronucleata. The published accounts of the morphology and cultural characteristics of the various forms are compared and provide additional evidence. A more complete description is given, including distinctive characters previously omitted.The conjugation process of P. multimicronucleata in general resembles that of P. caudatum, most of the differences being due to the presence of four micronuclei instead of one. These each divide twice with characteristic figures, twelve of the sixteen daughter nuclei then degenerating. One of the remaining four splits to form a single pair of functional pronuclei in each cell. The two migratory pronuclei interchange as in P. caudatum. The synkaryon divides three times, and probably seven of these nuclei degenerate. The remaining one apparently undergoes two divisions. In most cases by six to eight hours after the conjugants separate two micronuclei of the four thus produced form enlarged macronuclear anlagen, the other two remaining as micronuclei. Each anlage divides within the next two or four hours, producing four macronuclear and four micronuclear analagen. Two fissions, each preceded by a division of the micronuclei, restore vegetative conditions.The process described above is compared with conjugation in P. bursaria, P. caudatum, and P. putrinum.
A study of the gastric glands of alligator mississippiensis
Authors: Staley Forest H. 
Published: February 2005

AbstractA review of the literature of the gastric glands of reptiles shows marked differences of opinion concerning the nature and character of the cells composing the gastric glands.The present investigation of the gastric glands of the alligator has been carried out by histochemical and physiological experiments, rather than by the usual morphological methods, but the results can be stated both in terms of structure and function.
The surface epithelial cells and those lining the gland pits in the fundic, cardiac, and pyloric regions of the stomach of the alligator are not strictly comparable functionally to the mucous cells of mammals.
The cells composing the necks and bodies of the glands in the fundus, according to histochemical reactions, are parietal cells.
Certain cells lying beneath the columnar epithelial cells lining the lumen of the stomach and the foveolae react to one method of fixation and staining as do the chief cells of mammalian material.
The results of the experiment with the vital dye, neutral red, show that the cells of the gastric pits, the necks and bodies of the glands in the fundus of the alligator's stomach, react identically as those of the mammalian stomach.
The gastric juice of the alligator is acid to litmus‐paper and contains a free mineral acid.
Experimental and cytological studies on bisexual and hermaphrodite free‐living nematodes, with special reference to problems of sex
Authors: Honda Hikokuro 
Published: February 2005

AbstractHermaphroditic gonads of Rhabdites elegans can be distinguished in early developmental stages, but oogonia cannot be told from spermatogonia. Certain peculiar males show developmental processes approaching those of hermaphrodites. More eggs are produced by a hermaphrodite than there are sperm with which to fertilize them. Such exhausted hermaphrodites may be mated with males and produce fertile eggs, but convincing evidence of cross‐fertilization is lacking. Unmated females of Diplogaster aerivora live longer than mated ones, but no difference was found in the males. Sexual instinct seems to be lacking in males of R. dolichura and R. elegans.Hermaphrodites mated with males produce many more male offspring than by self‐fertilization, but these do not exhibit sexual instincts. Females produced by cross‐fertilization are not pure females, nor have they been found at all in R. elegans or R. dolichura. After fertilization in these two species, both polar bodies are formed and the pronuclei fuse. Sex is determined by the form of sperm.
The histogenesis of cartilage and bone in the long bones of the embryonic fowl
Authors: Fell Honor B. 
Published: February 2005

AbstractThe development and cytology of cartilage and bone in the limbs from the fifty‐second hour of incubation to the first day after hatching are described.The chief points of interest arising from this study are: (1) Chondroblasts when liberated during cartilage resorption die and disintegrate. (2) All the long bones possess structures which, though not undergoing independent ossification, are homologous with the mammalian epiphyses. (3) Endochondral ossification occurs only in the epiphyses and ends of the diaphyses. (4) The marrow cavity contains multinucleated giant cells which appear to be formed by the fusion of degenerating cells.
The formation of the sex glands and germ cells of mammals I. The origin of the germ cells in the albino rat
Authors: Hargitt Geo. T. 
Published: February 2005

AbstractAn early segregation of germ cells and migration through a germ track into the gonad does not occur in the albino rat. The germ cells are produced only from the peritoneum of the genital region and their earliest formation is coincident with the thickening of the coelomic epithelium to form the genital ridge. This takes place eleven days after insemination in embryos of approximately 18 somites. Germ cells continue to form from the peritoneum during the early development of the gonad. The peritoneum of this region also produces mesenchyme, smaller cells of the gonads, and the germinal epithelium.The argument for the specific character of the germ cells in vertebrates and their continuity from the egg is based largely upon assumption, and not upon substantial observations, and must be discarded. Germ‐cell origin is a problem of cellular differentiatio, and not of early segregation.
The histology of the blood of perophora viridis (ascidian)
Authors: George W. C. 
Published: February 2005

AbstractThe blood of Perophora viridis is found to contain six types of cells: (1) Green cells, which have green‐colored fatty bodies embedded in clear cytoplasm. (2) Orange cells, with orange‐colored bodies of unknown composition in the cytoplasm. (3) Colorless berry‐like cells, with fluid‐filled vesicles in the cytoplasm. (4) Granular amoeboid cells. (5) Compartmental amoeboid cells, which have box‐like vacuoles containing brownian granules of a fatty substance. (6) Vesicular, signet‐ring type of cell having a single large vacuole. The cytological structure of these cells and their reaction to various dyes are described.An effort has been made to homologize the types of cells found in the blood of other ascidians with those found in Perophora.It is concluded that the variety of colors found in the cells of ascidian blood is due to the varying chemical states of the vanadium‐containing chromogen present in the cells.
The nature and inheritance of webbed toes in man
Authors: Straus William L. 
Published: February 2005

AbstractWebbing of toes or fingers in man is produced by a local arrest of development, causing retention of the normal embryonic webbing. This type of digital fusion involves only the skin, the skeleton being unaffected. The extensor tendons of the toes may sometimes be fused.Webbed digits occur normally in some marsupials, rodents, and insectivores, in a number of lemurs and catarrhines, and in the siamang and gorilla. They also may occur in varying degree in other Primates, notably Hylobates. An analysis of five new pedigrees together with those already published demonstrates that webbing of toes in man may be inherited in either a mendelian or sex‐linked manner. In one case this character follows the course of the Y‐chromosome.
The comparative morphology of the secondary sexual characters of elasmobranch fishes. The claspers, clasper siphons, and clasper glands. Memoir IX
Authors: Leigh‐Sharpe W. Harold 
Published: February 2005

AbstractSixteen species of the genus Scyllium are here considered and arranged in groups according to the accessory structures present on the claspers as follows:
Canicula, sufflans, ventriosum.
Catulus, stellare, capense, variegatum (var. pantherinus), umbratile.
Burgerii, hispida, bivium, anale, natalense, edwardsii.
Marmoratum, laticeps.

The structure of the wall of the oviduct and vagina is demonstrated, and it is shown that the epithelium of both is at first columnar, then ciliated in immature specimens; at maturity that of the vagina further undergoes by transitions a change to stratified. The walls are highly vascular, but contain no special glands.
The comparative morphology of the secondary sexual characters of elasmobranch fishes. The claspers, clasper siphons, and clasper glands, together with a dissertation on the Cowper's glands of Homo. Memoir XI
Authors: Leigh‐Sharpe W. Harold 
Published: February 2005

AbstractThe claspers of Centrina are adnate with the pelvic fin and bear a spine as in other Spinacidae. Mustelus canis resembles M. lunulatus rather than M. vulgaris. The claspers of Chiloscyllium end in a pointed spike. Pseudotriakis resembles the Carchariidae. The three North American Atlantic species of the genus Raia are considered, and R. laevis and R. erinacea are placed in the pseudogenus containing R. batis, and a new pseudogenus erected for R. ocellata. A gross and histological account is given of the Cowper's glands of Homo, and they are shown to be homoplastic with clasper glands, similar in structure, arrangement, development, and function.
The development of the scales of Acipenser ruthenus
Authors: Sewertzoff A. N. 
Published: February 2005

AbstractThe different kinds of scales characteristic of the adult sturgeon are described and the facts of ontogenesis which throw light on the history of these structures are presented.The scales of Acipenser are exclusively mesenchymatous and therefore are not morphologically comparable with the placoid scales of elasmobranchs. Salensky ('80) drew erroneous conclusions as a result of failure to study the earlier stages of ontogenesis. Goodrich ('03) has correctly described the ontogenesis of the lepidotrichia.The original form of ganoid scale was that of an elongated rhomb with a longitudinal crest on its external surface. The various forms of scales of the adult sturgeon have been produced by the differentiation of such a scale by change in size, shape, and the fusion of the different elements.The conclusions are extended to the entire family of Acipenseridae.