permeability properties of the bufo bufo bladder as affected by isoprenaline and vasopressin. | isoprenaline, a beta adrenergic agonist, strongly increases both transepithelial fluxes across the urinary bladder of bufo bufo; this effect is dose dependent, 10(-6)m being necessary for the maximal action. this effect is less selective than that of vasopressin: the ratio j urea/j thiourea is 3.8 under isoprenaline and 30.4 under vasopressin treatment. both hormones differently affect the permeability of a mainly liposoluble molecule, i.e. antipyrine: vasopressin increases antipyrine permeabili ... | 1989 | 2483813 |
epidermal tissue homeostasis: apoptosis and cell emigration as mechanisms of controlled cell deletion in the epidermis of the toad, bufo bufo. | in normal, non-expanding toad epidermis more cells are produced than needed to replace cells lost by moulting. by implication, cell deletion additional to moulting must take place. this paper deals with the mechanisms by which the "surplus" of cells is deleted, taking advantage of the fact that the ratio between cell birth rate (kb) and the rate of desquamation (kd), which in normal toads is 2 to 3, can be manipulated. in toads deprived of the pars distalis of the pituitary gland it is decreased ... | 1989 | 2501035 |
[experimental analysis of membrane potential changes during maturation of bufo bufo gargarizans oocytes]. | the full-grown oocytes obtained from toad (bufo bufo gargarizans) submitted in hibernation state or reared at 25-30 degrees c for several months, named hibernation oocyte or high temperature oocyte, had a membrane potential of -41.51 +/- 0.77 mv and -43.83 +/- 1.39 mv in ringer's solution respectively. the hibernation oocytes underwent gvbd (germinal vesicle breakdown) and membrane depolarization at 19 +/- 1 degree c after progesterone stimulation. the membrane potential was about -20 mv at the ... | 1989 | 2511712 |
[the reaction of tadpoles of the common toad (bufo bufo l.) to chemical signals from individuals of their own and other species]. | in behavioral experiments, toad tadpoles-recipients chose between two parts of test aquarium with chemical signals of donor tadpoles of the same or different (rana esculenta) species. the youngest studied tadpoles (43-45 stages) preferred the part of the aquarium with chemical cues from sibs as compared to non-sibs. no reliable difference in "non-sibs: water" system was observed. in "tadpoles of the same species: tadpoles of the other species" system, recipient tadpoles chose "their" part of the ... | 1989 | 2515677 |
comparative lectin-binding patterns in the epidermis and dermal glands of bufo bufo (l.) and xenopus laevis (daudin). | bouin-fixed and paraffin-embedded sections from the dorsal skin of bufo bufo and xenopus laevis were subjected to lectin histochemistry. a panel of biotinylated lectins (con-a, psa, lca, uea-i, dba, sba, sja, rca-i, bsl-i, wga, s-wga, pha-e and pha-l) and an avidin-biotin-peroxidase complex (abc) showed a species-specific compartmentalization of saccharides to certain parts of the epidermis and glandular domains. some marked histochemical differences between the two examined species adapted to f ... | 1989 | 2517585 |
distribution of renal calcitonin binding sites in mammalian and nonmammalian vertebrates. | calcitonin (ct), the hypocalcemic hypophosphatemic hormone, is present in many vertebrate species. the principal target organs for ct are, in mammals, kidney and bone, and in fish, bone and gill. we have investigated the presence of renal calcitonin binding sites in a fish (salmo gairdneri), two amphibians (bufo bufo and rana esculenta), two reptiles (pseudemys scripta and gekko gecko), and two birds (gallus domesticus and cothurnix japonica). we compared their distribution to a mammal, the rat ... | 1989 | 2555248 |
[the spectral characteristics of the electroencephalogram of the toad bufo bufo l. during the active and passive behavior of the animal in its circadian cycle]. | using implanted electrodes, studies have been made on spectral eeg characteristics in the forebrain and midbrain of the toad during diurnal cycle. it was shown that rest constitutes more than 2/3 of 24-hour period, being presented mainly by passive wakefulness. a form of rest was revealed which may be classified as a sleep-like one. | 1989 | 2596212 |
hydrins, hydroosmotic neurohypophysial peptides: osmoregulatory adaptation in amphibians through vasotocin precursor processing. | from neurointermediate pituitary glands of xenopus laevis and rana esculenta, previously unreported peptides termed hydrins, active on water permeability of frog urinary bladder and frog skin (brunn or "water-balance" effect), have been isolated and sequenced. these peptides seem to be derived from the pro-vasotocin-neurophysin precursor. hydrin 1, found in xenopus, has been identified as vasotocin c-terminally extended with the gly-lys-arg sequence; hydrin 2, found in rana, has been identified ... | 1989 | 2787509 |
[cytoplasmic membranes are involved in the regulation of bufo bufo gargarizans resuming meiotic division]. | | 1987 | 2834899 |
[effect of endogenous camp changes on the oocyte maturation of bufo bufo gargarizans]. | | 1987 | 2834900 |
nature of moulting control in amphibians: effects of cortisol implants in toads bufo bufo. | implantation of cortisol pellets in a dorsal lymph sac reduced the frequency with which toads replaced the strata cornea of the epidermis. except in a few cases, however, the replaced strata cornea were not shed as in a normal moult. the mean interval between replacements of strata cornea rose from about 9-10 days in control toads to about 18 days in intact toads bearing implants. removal of the cortisol pellets approximately 1 month after their insertion was followed by moulting on the fourth ( ... | 1988 | 2842220 |
mitochondrial monoamine oxidase activity during preneural developmental stages of bufo bufo. | monoamine oxidase specific activities against pea and 5-ht have been measured in mitochondria isolated from early embryos of bufo bufo. during the early development up to the neural fold stage, mao activity undergoes a continuous decrease that is more evident when pea is used as the substrate. the inhibition patterns of deprenyl and clorgyline demonstrate that, at the neural fold stage, both type a and b mao are present. both in eggs and embryos mao type a activity appears slightly more sensitiv ... | 1985 | 2861952 |
glutathione peroxidases and glutathione reductase activities during bufo bufo development. | glutathione peroxidases and glutathione reductase activities are expressed from the early stage of bufo bufo development. selenium-dependent and selenium-independent glutathione peroxidase activities fluctuated independently. the activity of selenium-independent was found to be higher than that of selenium-dependent glutathione peroxidase through all stages of development. glutathione reductase activity, after a slight fall from stage 4 to stage 7, constantly increased up to stage 25. | 1986 | 2869913 |
changes in monoamine oxidase activity by mitochondria isolated from late embryos of bufo bufo. | 1. monoamine oxidase activity has been assayed in mitochondria isolated from post-neural embryos (stages 14-25) of bufo bufo, using 5-ht and pea as substrates. 2. mitochondria isolated from stages 19 to 25 show an increasing ability in deaminating monoamines, pea being metabolized at a higher level with respect to 5-ht. 3. at all the examined stages 5-ht is metabolized by an enzyme corresponding to mao a, while pea, from stage 19, is largely deaminated by a semicarbazide-sensitive amine oxidase ... | 1988 | 2894273 |
different types of pinealocytes as revealed by immunoelectron microscopy of anti-s-antigen and antiopsin binding sites in the pineal organ of toad, frog, hedgehog and bat. | s-antigen- and opsin-immunoreactive sites were studied in the pineal organ of toad (bufo bufo), frog (rana tigrina), hedgehog (erinaceus roumanicus) and bat (myotis myotis) by light microscopic avidin-biotin-peroxidase and electron microscopic immunoglobulin-gold (immunogold), protein a-gold and avidin-biotin-ferritin techniques. the corresponding retinas served as reference tissues. a large number of photoreceptors of toad and frog pineal organ exhibited either strong or weak s-antigen immunore ... | 1986 | 2937652 |
[effect of forskolin on the active transport of sodium and on the permeability of skin isolated from bufo bufo]. | | 1986 | 3024675 |
mauthner neurons survive metamorphosis in anurans: a comparative hrp study on the cytoarchitecture of mauthner neurons in amphibians. | giant medullary neurons were revealed in adult xenopus laevis and rana esculenta following hrp injections to the spinal cord. these neurons were identified as mauthner neurons because (1) they have the same position and orientation as the larval mauthner neurons, i.e., they lie at the level of the viiith nerve root. (2) they have two large dendritic trees that for each species are similar to those of the larval mauthner neurons, (3) they are clearly distinguishable from other large reticular neu ... | 1986 | 3081602 |
in vitro activation of amphibian dermal melanocytes by nicotine. | epidemiologic investigations have shown that nicotine could be a factor causing oral melanin pigmentation in man. nicotine was therefore tested on amphibian skin melanocytes. cell reactions were registered by spectrophotometry, in vitro light microscopy, photomicrography and light and electron microscopy. it was found that dermal melanocytes in the toad bufo bufo and the frog rana arvalis were activated by nicotine and that this activation was not mediated via beta-adrenergic receptors in melano ... | 1986 | 3085206 |
indacrinone (mk-196)--a specific inhibitor of the voltage-dependent cl- permeability in toad skin. | the effect of indacrinone (mk-196) on cl- transport through toad (bufo bufo) skin epithelium was studied by the voltage clamping technique. at the transepithelial potential, v = 50 mv (serosal bath grounded) the unidirectional fluxes, governed by a cl- self-exchange diffusion pathway, were not affected by 1 mm racemic mk-196 in the outer bath. likewise at v = o mv, the unidirectional fluxes as well as the active (net) inward flux of cl- were unaffected by mk-196. voltage clamping the epithelium ... | 1986 | 3088914 |
concentration dependence of halide fluxes and selectivity of the anion pathway in toad skin. | the isolated toad (bufo bufo) skin was mounted under voltage-clamp conditions in a chamber shown to cause no significant edge damage. the serosal side of the skin was bathed with nacl-ringer's, and the passive voltage-sensitive anion conductance studied in its fully voltage activated state, v = -80 mv (apical bath negative). the active sodium currents were eliminated by replacing external na+ with k+. with [cl-]o varying between 1.45 mm and 110 mm (gluconate substitution) and [i-]o = 3 mm, the t ... | 1986 | 3096079 |
periodic changes in the rigidity of activated anuran eggs depend on germinal vesicle materials. | the eggs of xenopus laevis and bufo bufo japonicus matured in vitro by progesterone were denuded and activated by electrical shock or pricking, and their diameters were determined periodically until the postactivation time equivalent to the 8- to 16-cell stage. normally matured eggs showed a quick rounding-up and flattening immediately after activation (activation response), followed by a periodic flattening and rounding-up (postactivation response) corresponding to the intervals of early cleava ... | 1986 | 3098597 |
the role of oviducal secretions in mediating gamete fusion in the toad, bufo bufo japonicus. | a fertilizing sperm of the anuran amphibians has to pass through the jelly envelopes and the vitelline envelope (ve) before making a successful fusion with the egg plasma membrane. of these the jelly envelopes, secreted by the long pars convoluta (pc) portion of the oviduct, have long been known to be indispensable for the sperm entrance in the egg. the most recent experiments employing dejellied uterine eggs of the toad, bufo bufo japonicus, revealed that the jelly plays its role in fertilizati ... | 1986 | 3103379 |
[estimation by toads of the distance to the moving objects and their true size: neuroethological and comparative aspects]. | in two sets of experiments, studies have been made on the parameters by which the toad bufo bufo estimates the neighbour and remote moving objects. in absence of the structural surrounding, a dark target with a diameter 17.2 degrees (3 cm at a distance of 10 cm) and with the rate of movement 36, 72 and 145 degrees/sec evoked in toads only feeding turns; at the rates 72 and 145 degrees/sec, together with these turns, animals usually fired with their tongues to the direction of the target, reveali ... | 1987 | 3105203 |
amphibian optokinetic after nystagmus: properties and comparative analysis in various species. | optokinetic nystagmus and after nystagmus were studied in six amphibian species, three urodeles and three anurans. it was demonstrated that two of the urodeles, hydromantes italicus and salamandra salamandra, display a relatively well-developed optokinetic after nystagmus, which is less pronounced in bombina variegata and nearly absent in bufo bufo, rana temporaria, and tylototriton verrucosus. these results indicate a certain degree of velocity storage in the optokinetic reflex of some amphibia ... | 1986 | 3105809 |
glutathione transferase activity during bufo bufo development. | high levels of glutathione transferase activity were measured during the development of the embryos of bufo bufo including unfertilized eggs. after stage 4 glutathione transferase activity gradually decreased until stage 25 when the minimum was reached. no change in the number of isozymes was noted during development according to isoelectric focusing analysis performed on the cytosolic fractions of selected stages. | 1987 | 3107890 |
edge preference of retinal and tectal neurons in common toads (bufo bufo) in response to worm-like moving stripes: the question of behaviorally relevant 'position indicators'. | previous experiments have shown that during prey-catching behavior (orienting, snapping) in response to a worm-like moving stripe common toads, bufo bufo (l.) exhibit a contrast- and direction-dependent edge preference. to a black (b) stripe moving against a white (w) background (b/w), they respond (r*) preferably toward the leading (l) rather the trailing (t) edge (rl* greater than rt*), thus displaying 'head preference'. if the contrast-direction is reversed (w/b), the stripe's trailing edge i ... | 1987 | 3114477 |
orientation behaviour of toads (bufo bufo) displaced from the breeding site. | the sensory basis and spatial range of orientation to the breeding site were studied in the toad bufo bufo, during two breeding seasons. toads were displaced passively from their breeding pond and fitted with a tracking device to record the path of migration in individuals. the directional choice and the straightness of trails after release were used to quantify the effect of experimental treatments. in both years, control (untreated) toads headed to the breeding site with the same precision at ... | 1987 | 3119823 |
ultrastructural analysis and cholinesterase activity in the brain capillaries of bufo bufo and rana esculenta. | we have investigated the structure and the cholinesterase features of the brain capillaries in two adult amphibians (rana esculenta and bufo bufo). we found that brain capillaries are un-fenestrated and the endothelial cell edges are joined by tight junctions. the brain capillaries in both species are characterized by high levels of ache. this enzyme is only localized in the basal membrane, whereas we have found the reaction product neither in the endoplasmatic reticulum nor in the golgi apparat ... | 1987 | 3121723 |
morphology of the oral disc of bufo bufo (salientia: bufonidae) tadpoles. | the fully developed oral disc of the tadpole of bufo bufo consists of dorsal and ventral labia bearing, respectively, two and three ridges bearing numerous horny denticles, a horny beak provided with jaw sheath serrations, and large lateral papillae that are borne by two cutaneous plicae. as development progresses toward metamorphosis, these structures gradually regress until they disappear. each cusped clavate labial denticle adheres, by means of a thin peduncle, to a similar labial denticle fi ... | 1988 | 3123703 |
preparation and characterization of the major isotype of parvalbumin from skeletal muscle of the toad (bufo bufo japonicus). | the major isotype of parvalbumin has been isolated from the skeletal muscle of the toad, bufo bufo japonicus. unlike the skeletal muscle of every frog so far examined (rana esculenta, rana temporaria, and rana catesbeiana), which contains two major isotypes of parvalbumins, toad skeletal muscle has been shown to contain only one isotype, but the content of parvalbumin in toad skeletal muscle was similar to the sum of those of the two isotypes in skeletal muscles of frogs. this feature of toad sk ... | 1987 | 3125161 |
[morphogenesis of the gonads and bidder's organs in young specimens of bufo bufo experimentally deprived of a large portion of their germ cells. i. premetamorphic stages]. | | 1987 | 3128198 |
[morphogenesis of the gonads and bidder's organs in young specimens of bufo bufo experimentally deprived of a large portion of their germ cells. ii. premetamorphic and postmetamorphic stages]. | | 1987 | 3128199 |
riesenzellen, goblet cells, leydig cells and the large clear cells of xenopus, in the amphibian larval epidermis: fine structure and a consideration of their homology. | the origin, fate and fine structure of the epidermal riesenzellen of larvae of bufo bufo, have been described by electronmicroscopy throughout their ontogeny. riesenzellen are uncommon in the epidermis relative to the epithelial cells. in young larvae they differentiate from basal epithelial cells, which enlarge and become rounded, lucent and glandular, some at least to open at the epidermal surface. they have disappeared by the end of metamorphosis. among amphibian larval specialized cells of t ... | 1988 | 3135114 |
action of forskolin on non-electrolyte permeability across the urinary bladder of bufo bufo as compared to that of various hormones. | 1. forskolin, an activator of adenyl-cyclase in a receptor-independent manner, mimics the adh effect on the urea and thiourea permeabilities across the toad bladder. 2. however, differently from adh, forskolin increases the erythritol permeability across the tissue and this effect is not reproduced by two substances increasing the urea permeability (8-brcamp and isoprenaline). most probably this effect of forskolin does not involve the camp generating system. | 1988 | 3137118 |
variety of structures developing after contralateral limb bud graftings on the anuran larva bufo bufo. | | 1988 | 3137460 |
influence of stationary and moving textured backgrounds on the response of visual neurons in toads (bufo bufo l.). | previous studies have shown that configurational prey recognition in common toads is performed by feature-analyzing functional units consisting of assemblies of connected neurons such as retinal (classes r2, r3), tectal [classes t5(1), t5(2), t5(3)], and pretectal (class th3) cells. in the present paper, effects of textured backgrounds on the response of these neurons to a configurational moving stimulus have been tested quantitatively. (1) in all investigated neurons, neither the overall activa ... | 1988 | 3142636 |
metabolic costs of growth and maintenance in the toad, bufo bufo. | metabolic costs of growth and maintenance were determined from the relationship m (metabolism) = m + ng (growth), where m is the metabolic rate at the feeding level at which growth is zero. in the past, the slope n was interpreted as indicating the metabolic costs of growth, and the costs of maintenance that arise with the increase in body mass were disregarded. these costs are included in n. in female toads, bufo bufo, feeding at different rates, the uncorrected value of n was 0.44, when metabo ... | 1988 | 3142962 |
the demonstration of the spindle fiber attachments in the amphibian liver and sperm nuclei by the sera from scleroderma patients. | the isolated liver nuclei and the mature sperm nuclei from rana nigromaculata and bufo bufo asiaticus had been investigated by indirect immunofluorescence method with anti serum specific to the spindle fiber attachments (sfas) from the scleroderma patients with crest syndrome. it was found that in the isolated liver nuclei and the mature sperm nuclei of these animals there are discrete speckles which bind the antibody specific to the sfas. the maximum number of these speckles counted in a single ... | 1985 | 3879774 |
the effect of acetylcholine on neurones of the amphibian nucleus isthmi. | in the bird, histochemical and biochemical data suggest that the tectal input into nucleus isthmi is of a cholinergic nature. in the present study the response of toad (bufo bufo gargarizans) isthmic neurones to acetylcholine was investigated using conventional extracellular recording techniques and ionophoresis. the results show isthmic cells to be strongly excited by acetylcholine (ach), whereas neurones in the neighbouring areas show minimal sensitivity. atropine sulphate completely blocked t ... | 1985 | 3918767 |
analysis of the secretions of the subcommissural organs of several vertebrate species by use of fluorescent lectins. | the glycoprotein secretions of the subcommissural organ were analyzed with the use of nine fluorescent lectins, specific to different sugar moieties. after exposure to concanavalin a a bright fluorescence was observed in the ependymal cells of the subcommissural organs of all vertebrates studied (lampetra planeri, ameiurus nebulosus, bufo bufo, lacerta vivipara, gallus gallus, rattus norvegicus, ovis aries). the fluorescence is abolished by the competitive sugar, alpha-d-mannopyranosyl. the inte ... | 1985 | 3919951 |
ultrastructural investigation on the myelinated fibres in toad medulla oblongata during metamorphosis. | the ultrastructure of myelinated fibres in the ventro-medial area of medulla oblongata of metamorphosing bufo bufo was studied. in the first stages of metamorphosis the fibres show normal distribution of the axonal organelles, while in the myelin sheaths the lamellae appear detached from one another with an irregular period and absence of the intra-period line. in the middle and final stages of metamorphosis there are myelin sheaths like those described above, but there are others with compact l ... | 1985 | 3921606 |
temperature-dependent calcium sensitivity changes in skinned muscle fibres of rat and toad. | single mechanically skinned muscle fibres of different types (fast- and slow-twitch mammalian; slow and twitch amphibian) were successively activated in solutions of various ca2+ concentrations at different temperatures. an increase in temperature from 5 to 22 degrees c reversibly shifted the isometric steady-state force-pca curves towards higher ca2+ concentration for individual fibres of each of the muscle types. a further increase in temperature to 35 degrees c in mammalian fibres resulted in ... | 1985 | 3921690 |
5,6-dihydroxyindole oxidation by mammalian, mushroom and amphibian tyrosinase preparations. | the oxidation of 5,6-dihydroxyindole by tyrosinases from mushroom, harding-passey melanoma, bovine eye and bufo bufo embryo has been investigated. the apparent km values for this substrate were measured and found to be of the same order of magnitude as those for l-tyrosine and l-3,4-dihydroxyphenylalanine, as reported in the literature (5 x 10(-4) m). the 5,6-dihydroxyindole oxidases of mushroom and t4 melanoma isozyme are sensitive to phenylthiourea, while, on the other hand, those from crude p ... | 1985 | 3926006 |
effects of ono-3122 (an enhancer of pgh2 production) and oky-1581 (an inhibitor of txa2 production) on the vasopressin-induced water flow in the toad bladder. | the effects of 1-iodo-3-aminomethyl-5,6,7,8-tetrahydro-2-naphthol (ono-3122) which increases endogenous pgh2, and sodium (e)-2-methyl-3-[4-3-pyridylmethyl)phenyl]-2-methylpropenoate (oky-1581) which inhibits thromboxane a2 synthesis, on vasopressin-induced osmotic water flow in the bladder of the toad, bufo bufo japonicus, were examined. ono-3122 significantly inhibited the vasopressin-induced water flow at a concentration of 1 x 10(-4) m. oky-1581 inhibited the vasopressin-induced water flow at ... | 1985 | 3927326 |
histochemistry of the juxtaglomerular apparatus in the toad bufo bufo. acid phosphatase activity of the epitheloid cells in the glomerular afferent arterioles. | histochemical techniques for acid phosphatase activity applied to kidney tissue of the toad bufo bufo demonstrate that a high enzyme activity is present in the dense granules of the proximal tubule cells, but also in the media cells in the wall of the glomerular afferent arterioles. the acid phosphatase activity is confined to the characteristic granules in these juxtaglomerular cells, which therefore are lysosomal in nature. | 1985 | 3927893 |
epidermal tissue homeostasis. i. cell pool size, cell birth rate and cell loss by moulting in the intact toad, bufo bufo. | toad epidermis is a suitable model for studies on tissue homeostasis because cell pool size, influx into and efflux from the cell pool can be easily determined. the cell pool size was obtained by cell counting on photomicrographs, the influx (cell birth rate) was assessed by the metaphase-arrest technique, and the efflux (cell loss by moulting) assessed by counting the number of cells in the corneal layer and recording of intermoult periods. the importance of the methods for assessing these para ... | 1985 | 3928164 |
the efferent vestibular neurons in the toad (bufo bufo l.): their location and morphology. a horseradish peroxidase study. | retrogradely labeled neurons are observed in the central nervous system of the toad after peripheral application of peroxidase to the anterior and posterior stumps of the viiith nerve. these efferent vestibular neurons are localized in the brainstem only ipsilaterally to the treated nerve; they are restricted within a region close to the motor nucleus of the viith nerve, outside the vestibular nuclear complex, and are predominantly localized to the borders between the gray and white matter in an ... | 1985 | 3930000 |
immunoelectron microscopic localization of renin in the juxtaglomerular cells of the amphibian bufo bufo. | the ultrastructural localization of renin in the juxtaglomerular apparatus of the kidney of the toad bufo bufo has been examined using an immunogold staining method for electron microscopic immunocytochemistry and an antiserum to renin isolated from the submandibular gland of the mouse. renin immunoreactivity was confined to lamellated granules in the cytoplasm of epitheloid or juxtaglomerular cells in the glomerular afferent arterioles and also in the media cells of larger arteries. mouse kidne ... | 1985 | 3935511 |
the antidromic activation of tectal neurons by electrical stimuli applied to the caudal medulla oblongata in the toad, bufo bufo l. | in order to specify the tectal projection to the bulbar/spinal regions, the antidromic responses of the physiologically identified tectal neurons as well as the gross antidromic field responses in the optic tectum to electrical stimuli applied to the caudal medulla were examined in the paralyzed common toad, bufo bufo. the antidromic field potential was recorded in the optic tectum in response to electrical stimuli applied to the ventral paramedian portion of the contralateral caudal medulla (wh ... | 1985 | 3939244 |
[experimental histophysiology of thyrotropic function in the toad bufo bufo l]. | | 1969 | 4100760 |
[action of goitrogens on tadpoles of the toad, bufo bufo l]. | | 1969 | 4100800 |
structure of the toad epidermis during the moulting cycle. l. light microscopic observations in bufo bufo (l.). | | 1973 | 4132105 |
location of inexchangeable sodium in the nucleus and cytoplasm of oocytes of bufo bufo exposed to sodium-free solutions. | 1. in oocytes exposed to ringer solution in which li substitutes for na, 13-62% na is inexchangeable with li.2. nuclei of oocytes isolated by dissection in salt solutions swell irrespective of the concentration or ionic components of the solution. when isolated in 4% bovine albumin solutions, swelling is negligible.3. when the nuclei of cells exposed to li are isolated in 4% albumin solution, less than 6% of the inexchangeable na is found in the nucleus, while 36-88% of it is found in the cytopl ... | 1973 | 4197608 |
the morphology of the juxtaglomerular apparatus in the toad, bufo bufo. a light microscopic study. | | 1973 | 4198009 |
pattern of recruitment of oocytes to second growth phase in normal toads, and in hypophysectomized toads, bufo bufo bufo (l.), treated with gonadotropin (hcg). | | 1973 | 4198987 |
metabolism of 14c-histamine in amphibians (bufo bufo) and reptiles (pseudemys scripta and testudo hermanni). | | 1974 | 4205336 |
seasonal and hormonally induced changes in the serum level of the precursor protein vitellogenin in relation to ovarian vitellogenic growth in the toad bufo bufo bufo (l.). | | 1974 | 4205560 |
contribution to study of the arterial supply of the gastrointestinal tract of the toad (bufo bufo). | | 1973 | 4205613 |
[consequences of experimental augmentation of the number of medullary cells on early organogenesis of the embryonal gonad of the common toad, bufo bufo l]. | | 1973 | 4205919 |
germ cell migration in toad (bufo bufo): effect of ventral grafting of embryonic dorsal regions. | | 1974 | 4206639 |
the compliance of contracting skeletal muscle. | 1. the method of controlled releases was used to obtain tension-extension curves in toad (bufo bufo) sartorii under a variety of conditions at 0 degrees c.2. the curves obtained were approximately linear over a considerable range of force (0.4p(0) to p(0)) if the releases were given from the plateau of tetanic tension. the slope of this linear region was little affected by changes of release velocity in the range 10-120 mm/sec.3. such changes as did occur with alterations in release velocity cou ... | 1974 | 4207658 |
[ganglion cell types in the retino-tectal projection in the toad bufo bufo (l.)]. | | 1974 | 4209065 |
effect of exogenous estradiol-17 beta on vitellogenic oocyte growth in ovaries of the toad bufo bufo bufo (l.) during the postspawning period. | | 1974 | 4209705 |
mechanisms regulating ovarian cycle in the toad bufo bufo bufo (l): role of presence of second growth phase oocytes in controlling recruitment from pool of first growth phase oocytes. | | 1974 | 4209938 |
[arterial system of gastrointestinal tract in the toad (bufo bufo)]. | | 1974 | 4211307 |
neuronal correlates of seasonal changes in contrast-detection of prey catching behaviour in toads (bufo bufo l.). | | 1974 | 4212194 |
[comparative analysis of the intraspecific nuclear graft in bufo bufo l., bufo calamita laur., bufo viridis laur. (anourous amphibia)]. | | 1974 | 4214244 |
inhibition of toad (bufo bufo l) retinal on-off and off-ganglion cells via active eye closing. | | 1974 | 4215219 |
an ultrastructural study of the juxtaglomerular apparatus in the toad, bufo bufo. | | 1974 | 4216402 |
intracellular sodium and potassium concentrations in toad and frog oocytes during development. | 1. during growth of oocytes of bufo bufo from approximately 700-2000 mum in diameter, intracellular na rose from 20 to 120 m-mole/l. cell water while k fell from 120 to 15 m-mole/l. cell water.2. in rana temporaria na similarly rose from 9 to 190 m-mole/l. cell water and k fell from 126 to 28 m-mole/l. cell water.3. at the same time in both bufo and rana the ouabain-sensitive na efflux, the ouabain-insensitive na efflux, and the total na influx all increased.4. it is concluded that the predomina ... | 1974 | 4216627 |
intracellular sodium and potassium concentrations in oocytes of bufo bufo at the beginning of maturation. | 1. during the first phase of maturation in oocytes of bufo bufo, after the growth phase but before ovulation, intracellular na rises to 120 m-mole/l. cell water while k falls to 15 m-mole/l. cell water.2. at the same time, the ouabain-insensitive na efflux and total na influx both increase while the ouabain-sensitive na efflux is unchanged. | 1974 | 4216628 |
ionic relations and electrical properties of isolated oocytes of bufo bufo with special reference to removal of extracellular chloride. | 1. the efflux rate coefficients of sodium, potassium and chloride from immature oocytes of the toad bufo bufo have been measured and found to be respectively, 0.0069, 0.0023 and 0.0034 min(-1).2. replacement of external chloride by sulphate resulted in a fall in chloride efflux of about 50%. this has been interpreted in terms of exchange diffusion.3. the membrane conductance has been measured and found to be 0.14 x 10(-3) mhos cm(-2) in good agreement with the value calculated from the flux data ... | 1974 | 4217360 |
studies on the gastrulation of amphibian embryos: pseudopodia in the gastrula of bufo bufo japonicus and their significance to gastrulation. | | 1974 | 4219025 |
carbohydrate metabolism in normal and thyroidectomized bufo bufo adult males. | | 1969 | 4240089 |
[biochemical determination of the phosphomonoesterase activity in the intestine and kidney of bufo bufo bufo l]. | | 1966 | 4287312 |
the chemical synthesis and biological oxidation of 7-alpha-hydroxy[26-14c]cholesterol, 7-dehydro[26-14c]cholesterol and 26-hydroxy[26-14c]cholesterol. | 1. 26-hydroxycholesterol was obtained by reducing the methyl ester of (+/-)-3beta-hydroxycholest-5-en-26-oic acid, which was synthesized from 25-oxonorcholesterol. 2. methods for preparing 7alpha-hydroxycholesterol and 7-dehydrocholesterol were modified to allow the micro-scale preparation of these [(14)c]sterols from [26-(14)c]-cholesterol. 3. 26-hydroxycholesterol was oxidized more readily than 7alpha-hydroxycholesterol, 7-dehydrocholesterol or cholesterol by mitochondrial preparations from li ... | 1966 | 4287406 |
function and cytology of the normal and autotransplanted pars distalis of the hypophysis in the toad bufo bufo (l). | | 1966 | 4290015 |
blood glucose in male toads (bufo bufo): annual variation and hormonal regulation. | | 1969 | 4305331 |
[further experimental studies on the mechanism of action of neurohormone d from periplaneta americana (l) on the "biologic model" of bufo bufo urinary bladder: influencing of na+-transport]. | | 1971 | 4328748 |
hypophysial corticotropic function and its hypothalamic control in bufo bufo (l.) evaluated by the plasma concentration of corticosterone. | | 1972 | 4335777 |
[the ultrastructure of the adenohypophysis in the toad, bufo bufo l. 3. cell differentiation in the pars distalis during larval growth]. | | 1972 | 4336302 |
heat production and fluorescence changes of toad sartorius muscle during aerobic recovery after a short tetanus. | 1. the time course of the aerobic recovery following a 0.5 sec tetanus at 20 degrees c of the sartorius muscle of the toad bufo bufo, equilibrated in bicarbonate-co(2) ringer solution, has been followed by recording simultaneously the heat production and the fluorescence excited by ultra-violet light at 366 nm.2. the fluorescence light emitted in these conditions in the region of 450 nm monitors the state of oxidation-reduction of the nicotinamideadenine dinucleotides (nad(+)-nadh). after a shor ... | 1972 | 4339903 |
rates of disappearance from blood and biological potencies of mammalian gonadotropins (hcg and ovine lh) in the toad bufo bufo bufo (l.). | | 1974 | 4370312 |
mono- and triphosphate nucleotides, adenylatecyclase and phosphodiesterase activities in the intestine of normal or prolactin-treated bufo bufo larvae. | | 1974 | 4374408 |
non-electrolyte permeability across bufo bufo gall-bladder. | | 1971 | 4397616 |
a progesterone-like factor detected by bioassay in the blood of the toad (bufo bufo) shortly before induced ovulation. | | 1972 | 4621598 |
role of pars distalis and pars nervosa of the hypophysis in the water economy of the toad bufo bufo bufo (l.). | | 1972 | 4621599 |
monoamine oxidase in the neurohypophysis of the newt (cynops pyrrhogaster pyrrhogaster), the toad (bufo bufo japonicus) and the tortoise (clemmys japonica). | | 1972 | 4623962 |
[constitution of the hemoglobin of the toad bufo bufo spinosus. ii]. | | 1972 | 4623980 |
prolactin and growth hormone concentrations in the plasma of the toad bufo bufo (l.) following ectopic transplantation of the pars distalis. | | 1972 | 4625839 |
[autoradiographic study of various parameters of cell proliferation during natural metamorphosis of the toad bufo bufo l]. | | 1972 | 4629057 |
[ultrastructure of the adenohypophysis in the toad bufo bufo l. iv. modifications of the larval pars distalis after treatment with ptu]. | | 1972 | 4629898 |
[specific cell-mediated immunity in batrachians. ii. delayed hypersensitivity to bcg in the toad (bufo bufo l.)]. | | 1972 | 4630832 |
characteristics of aldosterone stimulated transport in isolated skin of the toad, bufo bufo (l.). | | 1972 | 4631249 |
[effect of temperature conditions on cell proliferation in the larva of the toad, bufo bufo l]. | | 1972 | 4631957 |
changes in the fine structure of the ovarian follicle of the toad (bufo bufo) prior to induced ovulation. | | 1973 | 4633493 |
salt adaptation in bufo bufo. | 1. the capacity of adaptation of toads (bufo bufo) to environments of high salinity was studied and the relative importance of skin, kidney and urinary bladder in controlling the balance of water and salt was assessed.2. toads were kept in nacl solutions of 20, 50, 110, 150 and 220 mm and studied in their fourth week of adaptation. a group of animals considered as ;control' was kept in wet soil with free access to water. plasma, ureter urine, and bladder and colon contents were analysed for sodi ... | 1973 | 4633911 |
the demonstration of renal juxtaglomerular granules and the evaluation of the index of granulation in the toad, bufo bufo. | | 1969 | 4884709 |
gonadotropic function of the autotransplanted pituitary gland in the female toad bufo bufo (l.). | | 1968 | 4905276 |
[the ultrastructure of the adenohypophysis in the toad, bufo bufo l. i. identification of cell types and comparison of the results obtained with different fixations]. | | 1970 | 4910950 |