Publications

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the retinotectal projection from a double-ventral compound eye in xenopus laevis. 19744206638
immunoglobulin classes in xenopus laevis. 19744211233
[energy production during oocyte maturation in xenopus laevis]. 19744211428
the cortical response in xenopus laevis ova. 19744213423
[effect of osmotic loading on the claw frog xenopus laevis]. 19664230651
the ultrastructural localization of acid phosphatase, alkaline phosphatase and adenosine triphosphatase in induced goitres of xenopus laevis daudin tadpoles. 19674233134
[comparative electrophysiologic study of the motor and sensory myelinized nerve fibers in rana esculenta and xenopus laevis]. 19674234703
the role of cell division in xenopus laevis skin gland development. 19694242958
stimulation of cell division in larval kidney (xenopus laevis) by rat kidney antiserum. 19714250774
substrate-dependent beta-hydroxy steroid dehydrogenase activity in the gonads of the clawed toad (xenopus laevis daud.). 19724260704
dopamine- -hydroxylase activity in the skin of xenopus laevis in relation with pigment migration. 19734265946
regulation of mitosis in the embryonic kidney (xenopus laevis) by kidney growth inhibitor (chalone). 19734271043
the mixed leukocyte reaction in the toad xenopus laevis: a family study. 19734272812
the thymus during the ontogeny of the toad xenopus laevis: growth, membrane-bound immunoglobulins and mixed lymphocyte reaction. 19734273637
histochemical characteristics of cement-gland mucin in xenopus laevis. 19744275458
mechanical properties of muscle spindles in xenopus laevis. 19744276239
[electron microscopy studies of the skin of xenopus laevis in larval and metamorphosis stages following application of potassium perchlorate]. 19654286767
an analysis of some inhibitory mechanisms in the spinal cord of the frog (xenopus laevis). 19684301854
[experimental studies on the relation between the thyroid gland and hypophysis during the larval development and metamorphosis of xenopus laevis daudin]. 19674302119
ultrastructural observations on the droplets of experimentally-induced goitres in xenopus laevis with especial reference to the development of uhlenhuth colloid cells. 19684302610
effect of angiotensin-ii-amide on renal function in the clawed toad, xenopus laevis daudin. 19694306145
kinetic studies on the biosynthesis of corticosteroids in vitro from exogenous precursors by the interrenal glands of the normal, corticotrophin-treated and adenohypophysectomized xenopus laevis daudin. 19704317284
the role of adenosine 3'-5'-cyclic monophosphate and catecholamines in the pigment migration process in xenopus laevis. 19704317518
the effect of acth and corticosteroids on carbohydrate metabolism during the metamorphosis of xenopus laevis. 19714322553
the pharmacology of efferent synapses in the lateral-line system of xenopus laevis. 19714326222
cytokinesis and cytochalasin-induced furrow regression in the first-cleavage zygote of xenopus laevis. 19714329592
electron microscopic study on the xanthophore differentiation in xenopus laevis, with special reference to their pterinosomes. 19724335114
hormonal regulation of the skin diffusional permeability to water during development and metamorphosis of xenopus laevis daudin. 19724335780
long-term cell culture of two differentiated cell types from the liver of larval and adult xenopus laevis. 19724336791
some pathological aspects of the spontaneous lymphoid tumour in xenopus laevis. 19724337642
biogenesis of mitochondria during xenopus laevis development. 19724337711
amino acid pools in developing oocytes of xenopus laevis. 19724339521
development of the mauthner cell in xenopus laevis: a light and electron microscopic study of the perikaryon. 19724339562
effect of cyclic amp and cytochalasin b on tissue cultured melanophores of xenopus laevis. 19724344774
translation of encephalomyocarditis viral rna in oocytes of xenopus laevis.rna from encephalomyocarditis virus was injected into oocytes of xenopus laevis. after incubation of the oocytes in [(35)s]methionine, polyacrylamide gel electrophoresis showed that a new series of polypeptides had been synthesized. they were identical in size to the polypeptides that appeared in ascites cells after infection with this virus. electrophoretic and chromatographic analysis of the methionine-containing tryptic peptides from three of the induced polypeptides confirmed that they were ...19724345506
ultrastructural aspects of the nucleus infundibularis dorsalis in the caudal hypothalamus of xenopus laevis. 19734348310
the pneumonocytes in the lung of xenopus laevis. 19734352575
[changes in various biochemical values in the blood and liver of xenopus laevis females treated with estrogens]. 19724352832
effects of naja nivea venom on nerve, cardiac and skeletal muscle activity of the frog.1. the effects of 1 mg/ml whole naja nivea (cape cobra) venom, and of three different toxins isolated from it, on spinal reflex excitability and cardiac and skeletal muscle activity of the frog (xenopus laevis), were studied. isolated spinal cords, sciatic nerve-gastrocnemius muscle units and isolated heart preparations were used.2. synaptic efficiency and/or motoneurone excitability ceased totally and irreversibly after the application of whole venom within 18.5 minutes. the application of alph ...19734354326
new membrane formation during cytokinesis in normal and cytochalasin b-treated eggs of xenopus laevis. i. electron microscope observations.a method is described for measuring and calculating the preexisting surface in uncleaved xenopus eggs and the rate of surface growth in cleaving eggs. surface-marking experiments with cytochalasin b-treated eggs show that the unpigmented surface grows by de novo formation and not by expansion of preexisting pigmented surface. the onset of new surface formation during first cleavage was studied by using transmission electron microscope and scanning electron microscope techniques. at 3-4 min and a ...19734356573
the effect of cytochalasin b on pigment dispersion and aggregation in perfused xenopus laevis tailfin melanophores. 19744360295
ultrastructural changes associated with uv irradiation in the "germinal plasm" of xenopus laevis. 19744362762
the reaction of the preoptic nucleus of xenopus laevis to osmotic stimulation. an enzyme cytochemical investigation. 19744363193
inhibition of ribosomal rna synthesis in neurula cells by extracts from blastulae of xenopus laevis. 19734363801
biochemical changes during progesterone-induced maturation in xenopus laevis oocytes. 19744365213
actions of antifertility chemicals on xenopus laevis spermatozoa in vitro. 19744365531
28-s rna from xenopus laevis contains a sequence of three adjacent 2'-o-methylations. 19744365812
characteristics of the sensory discharge of the muscle spindle in xenopus laevis. 19744366467
the degradation of ribonucleic acids injected into xenopus laevis oocytes. 19744370441
ultrastructural and cytochemical localization of the storage sites of monoamines in the paraventricular organ of xenopus laevis tadpoles. 19744371980
protein kinase activities during maturation in xenopus laevis oocytes. 19744373001
hormone-induced maturation of xenopus laevis oocytes: effects of different steroids and study of the properties of a progesterone receptor. 19744374402
in vitro characterization of adrenergic receptors controlling skin gland secretion in two anurans rana pipiens and xenopus laevis. 19694390632
intracellular enzymes and -ketolic steroids of the gonads in xenopus laevis daud. 19714400579
oxidative enzymes and -ketolic steroids in the interrenal cells of the south african clawed toad xenopus laevis daud. 19714400580
a chemical and pharmacological study on the role of catecholamines in the dispersion reaction of xenopus laevis. 19724401401
possible involvement of - and -receptors in the natural colour change and the msh-induced dispersion in xenopus laevis in vivo. 19724402096
under-replication of ribosomal cistrons in polytene chromosomes of rhynchosciara.dna preparations obtained from several tissues of rhynchosciara americana and two related species, r. milleri and r. papaveroi, were hybridized to r. americana rrna. the percentage of hybridization was found to be higher in tissues with low polyteny than in tissues with high polyteny, suggesting a relationship between the amount of rdna and the tissue polyteny. this could be explained by under-replication of ribosomal cistrons in polytene cells, such as those from the salivary gland. only slight ...19744407049
formation and regression of inappropriate nerve sprouts during trochlear nerve regeneration in xenopus laevis. 19744418001
intercellular gap junctions in pigment epithelium cells during retinal specification in xenopus laevis. 19744423669
the decay of xenopus laevis mitochondrial rrna in the presence of ethidium bromide or actinomycin d. 19744425966
observations on early germ cell development and premeiotic ribosomal dna amplification in xenopus laevis.the origin of premeiotic ribosomal dna (rdna) amplification in germ-line cells of xenopus laevis has been examined using in situ rna-dna hybridization on cytological preparations, tritiated thymidine autoradiography, and isopycnic density gradient centrifugation. primordial germ cells (pgc), from the time they first become localized in the genital ridge at day no. 4 of development, until approximately day no. 22, remain in an extended interphase condition. during this time pgc do not incorporate ...19744426916
ultrastructure of xenopus laevis oocytes after injection of an extract from progesterone-treated oocytes. 19744431074
the effect of hydrocortisone on the sheep red cell response in adult xenopus laevis, the south african clawed toad. 19744436631
an analysis of acidic nuclear proteins during the development of xenopus laevis. 19744442125
hepatic melanosis and ageing in amphibia. a preliminary observation on two species of anura xenopus laevis and rana nigromaculata. 19744442478
metabolism of exogenous 4-14c-progesterone during early development of xenopus laevis. 19744442671
the cyclization of xenopus laevis 5 s dna. 19744444032
secondary structure maps of ribosomal rna and dna. i. processing of xenopus laevis ribosomal rna and structure of single-stranded ribosomal dna. 19744444053
[deranged axial growth of the xenopus laevis larva following elimination of the subcommissural organ]. 19744445814
sequence studies of the 5 s dna of xenopus laevis. 19744449128
an electron microscope heteroduplex study of the ribosomal dnas of xenopus laevis and xenopus mulleri. 19744453019
a study on gonadotropin action in the induction of oocyte maturation in xenopus laevis. 19744457129
regeneration and remyelination of xenopus tadpole optic nerve fibres following transection or crush.optic nerves of stage 54-56 xenopus laevis tadpoles were either transected or crushed, and subsequent wallerian degeneration, regeneration, and remyelination were examined. after 4 days, normal myelinated fibres were no longer present in the distal stump, and only a few unmyelinated fibres remained. after 10-13 days, the distal nerve consisted mainly of a core of reactive astrocytes with enlarged processes and scattered oligodendrocytes which persisted throughout the degenerative period. regener ...19744461769
the incorporation and fate of [35-s]-sulfate in the jelly coat of xenopus laevis eggs. 19744462853
an ultrastructural study of germ plasm in spermatogenesis of xenopus laevis. 19744463219
synthesis and localization of histone in xenopus laevis gametes. 19744464773
the translation of mammalian globin mrna injected into fertilized eggs of xenopus laevis i. message stability in development. 19744471721
changes in the polysome content of developing xenopus laevis embryos. 19744472028
the cell cycle of xenopus laevis cells in monolayer culture. 19744472348
transcription specificity of xenopus laevis rna polymerase a. 19744473382
arrangement of the 5-8 s rna cistrons in the genome of xenopus laevis. 19744473555
the pattern of concanavalin a-binding sites during the early development of xenopus laevis. 19744474060
protein synthesis directed by the rna from a plant virus in a normal animal cell.rna from tobacco mosaic virus can be translated inside oocytes of the frog xenopus laevis. the main product is a polypeptide with a molecular weight of 140,000. there is no evidence for coat protein synthesis, and it is unlikely that the polypeptide that is made contains either a whole or a partial coat protein sequence. the picture of translation of tobacco mosaic virus rna obtained using oocytes is very much simpler than that found using cell-free protein-synthesizing systems, in which a great ...19744474972
[dna polymerase of oocytes and ova of xenopus laevis: determination of molecular weights]. 19744475595
effects on protein synthesis of injecting synthetic polyribonucleotides into living cells.micro-injection into the oocytes and eggs of xenopus laevis was used to ascertain the effects of synthetic polyribonucleotides on protein synthesis in living cells. poly(u) and poly(a) were not translated detectably, nor did they change the rate of endogenous protein synthesis. the same was true of poly(g,u), poly(a,g,u), poly(a,c,g,u), g-u-g-(u)(n), a-(u)(n) and aug. in contrast, a-u-g-(u)(n) was a potent inhibitor of protein synthesis in the cell. this might be because it is initiated normally ...19744477956
studies on fertilization in xenopus laevis. 19744477973
synthesis of rna in oocytes of xenopus laevis during culture in vitro. 19744477995
calf crystallin synthesis in frog cells: the translation of lens-cell 14s rna in oocytes.14s rna isolated from calf-lens polyribosomes was injected into oocytes of the frog xenopus laevis. oocytes injected with 14s rna and buffer contained a protein resembling the a2 chain of calf alpha-crystallin; oocytes injected with buffer alone contained no crystallin-like material. alphaa2 crystallin polypeptides were identified by various criteria: urea-gel electrophoresis under acidic and basic conditions, gel electrophoresis in sodium dodecyl sulfate, n-terminal analysis, and paper chromato ...19724504377
[on the role of rna in gene amplification].a complex of ribosomal dna with rna has been isolated from ovaries of metamorphosing tadpoles of xenopus laevis. the complex is disrupted by treatments that destroy hydrogen bonds, and the sedimentation of the dna within the complex is sensitive to rnase. we suggest that the rna-ribosomal dna complex is an intermediate in the synthesis of amplified ribosomal dna and that the rna is a template. in addition, in a preliminary attempt to mimic the amplification process in vitro, we have demonstrated ...19724505650
an rna-dna complex intermediate in ribosomal gene amplification.an rna-ribosomal dna complex can be isolated from ovaries of xenopus laevis incubated in vitro during the amplification stage. a part of the rna present in the complex is resistent to rnase but becomes completely sensitive after heat denaturation, a treatment that also allows the separation of the rna from the dna. the size of the rna-ribosomal dna complex is strongly reduced after treatment with rnase. a small fraction of the rna present in the complex is complementary to the spacer region of t ...19724505651
specification of positional information in retinal ganglion cells of xenopus: stability of the specified state.in the normal development of retinotectal connections, the site in the tectum at which an optic fiber synapses is related to the position of its ganglion-cell body in the retina. how and when the ganglion cells acquire information about their positions is unknown, but the positional information that each ganglion cell will ultimately act upon is determined or specified at embryonic stages 28-32 in the clawed frog, xenopus laevis. here we report that once positional information has been so specif ...19724507610
microinjection of rabbit hemoglobin messenger rna into amphibian oocytes and embryos.after microinjection of hemoglobin mrna from rabbit reticulocytes (9s mrna) into xenopus laevis oocytes, the cytological structure remains normal. the peroxidase reaction does not show an accumulation of synthesized hemoglobin in the germinal vesicle. fertilized pleurodeles waltlii eggs synthesize rabbit hemoglobin after injection of 9s mrna; hemoglobin synthesis decreases as development progresses. micromeres and macromeres synthesize equal amounts of hemoglobin, despite the fact that the micro ...19734510295
different sequences for 5s rna in kidney cells and ovaries of xenopus laevis. 19734512331
isolation of messenger rna coding for mouse heavy-chain immunoglobulin.a method for purification of the mrna coding for heavy-chain protein of a mouse g(2a) myeloma (5563) is reported. complete myeloma protein (h(2)l(2)) specifically binds to the heavy-chain mrna, and the resultant rna-protein complex is precipitated with antiserum against 5563 myeloma protein. cytoplasmic rna isolated by this method showed two bands of 6.0 x 10(5) and 3.1 x 10(5) molecular weight when analyzed by acrylamide gel electrophoresis. the rna in the bands contained 1.5% and 8% a-rich reg ...19734515608
the translation of messenger rna injected in living oocytes of xenopus laevis. 19734521403
clustered arrangement of trna genes of xenopus laevis. 19744524767
the structure and evolution of ribosomal and 5s dnas in xenopus laevis and xenopus mulleri. 19744524770
agglutination of jelly coat and cortical granule components and the block to polyspermy in the amphibian xenopus laevis.a block to polyspermy in amphibians is established at fertilization by the conversion of the vitelline envelope to the fertilization envelope. in xenopus laevis a major ultrastructural change in the envelope at fertilization is the appearance of an electron-dense layer, termed the f layer, between the envelope and the inner-most jelly coat layer, j(1). the f layer is derived, at least in part, from materials released from the cortical granules. further definition of the origin and chemical natur ...19744525317
amplified ribosomal dna from xenopus laevis has heterogeneous spacer lengths.eco r(1) restriction endonuclease makes two cuts in each repeating unit of amplified ribosomal dna (rdna) from xenopus laevis. the locations of these cuts have been established by comparison of the secondary structure of single-stranded eco r(1) fragments (as visualized in the electron microscope) with that of x. laevis rrnas and of long strands of uncut rdna. of the two classes of fragments generated, the smaller one contains 90% of the 28s rrna gene, has a duplex molecular weight of 3.0 x 10(6 ...19744527647
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