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  • 1
    Electronic Resource
    Electronic Resource
    Characterization of a hemichordate fork head/HNF-3 gene expression (2000)
    Springer
    Development genes and evolution 210 (2000), S. 11-17 
    Details
    ISSN: 1432-041X
    Keywords: Key words Hemichordates ; Deuterostomes ; fork head/HNF-3 gene ; Vegetal plate cells ; Archenteron
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract  Based on anatomical and developmental similarities, hemichordates are thought to be most closely related to chordates. However, so far very few developmental genes have been characterized from hemichordates. To gain molecular insight into the developmental mechanisms involved in the origin and evolution of chordates, we investigated the expression of a fork head/HNF-3 (PfHNF3) gene in the acorn worm embryo. Chordate fork head genes are implicated in the formation of endoderm, notochord and floor plate. We found that a PfHNF3 transcript was first detected at the early blastula stage; the signal of in situ hybridization was found in the vegetal plate cells, invaginating endoderm and then in the archenteron. By the late gastrula and into the early tornaria larva stages, an intense signal remained in the anterior region of the archenteron, while the expression in the other regions of archenteron decreased. The intense signal was retained in the pharynx of the tornaria larva. A comparison of the pattern of PfHNF3 with that of HNF-3 genes of sea urchin, ascidian, amphioxus and vertebrate suggests a possible acquisition of new functions of the gene during deuterostome evolution.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/PL00008181
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  • 2
    Electronic Resource
    Electronic Resource
    GABAergic synaptic transmission modulates swimming in the ascidian larva (2005)
    Oxford, UK : Blackwell Science Ltd
    European journal of neuroscience 22 (2005), S. 0 
    Details
    ISSN: 1460-9568
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: To examine the role of the amino acid GABA in the locomotion of basal chordates, we investigated the pharmacology of swimming and the morphology of GABA-immunopositive neurones in tadpole larvae of the ascidians Ciona intestinalis and Ciona savignyi. We verified that electrical recording from the tail reflects alternating muscle activity during swimming by correlating electrical signals with tail beats using high-speed video recording. GABA reversibly reduced swimming periods to single tail twitches, while picrotoxin increased the frequency and duration of electrical activity associated with spontaneous swimming periods. Immunocytochemistry for GABA revealed extensive labelling throughout the larval central nervous system. Two strongly labelled regions on either side of the sensory vesicle were connected by an arc of labelled fibres, from which fibre tracts extended caudally into the visceral ganglion. Fibre tracts extended ventrally from a third, more medial region in the posterior sensory vesicle. Two rows of immunoreactive cell bodies in the visceral ganglion extended neurites into the nerve cord, where varicosities were seen. Thus, presumed GABAergic neurones form a network that could release GABA during swimming that is involved in modulating the time course and frequency of periods of spontaneous swimming. GABAergic and motor neurones in the visceral ganglion could interact at the level of their cell bodies and/or through the presumed GABAergic fibres that enter the nerve cord. The larval swimming network appears to possess some of the properties of spinal networks in vertebrates, while at the same time possibly showing a type of peripheral innervation resembling that in some protostomes.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1460-9568.2005.04420.x
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  • 3
    Electronic Resource
    Electronic Resource
    Steroidal saponins from the bulbs of Lilium longiflorum and their antitumour-promoter activity
    Amsterdam : Elsevier
    Phytochemistry 37 (1994), S. 227-232 
    Details
    ISSN: 0031-9422
    Keywords: HeLa cells ; Liliaceae ; Lilium longiflorum ; antitumou ; bulbs ; furostanol saponins ; phospholipid metabolism ; spirostanol saponins ; steroidal saponins
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Biology , Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://linkinghub.elsevier.com/retrieve/pii/0031-9422(94)85030-5
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  • 4
    Electronic Resource
    Electronic Resource
    Ring differentiation of the trans-decahydronaphthalene system via chemo-enzymatic dissymmetrization of its σ-symmetric glycol: Synthesis of a highly functionalized chiral building block for the terpene synthesis
    Amsterdam : Elsevier
    Tetrahedron Letters 34 (1993), S. 4539-4540 
    Details
    ISSN: 0040-4039
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://linkinghub.elsevier.com/retrieve/pii/0040-4039(93)88079-X
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  • 5
    Electronic Resource
    Electronic Resource
    Cellular uptake of hematoporphyrin derivative in KK-47 bladder cancer cells (1984)
    Springer
    Urological research 12 (1984), S. 143-146 
    Details
    ISSN: 1434-0879
    Keywords: Hematoporphyrin derivative ; Cellular uptake ; Human bladder cancer cell line ; Subcellular fractionation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The fluorescence emission spectra and degree of fluorescence polarization of hematoporphyrin derivative (HpD) have been investigated using HpD-containing KK-47 cells, PBS and cetyl trimethyl ammonium chloride (CTAC) micellar solutions. The fluorescence emission bands in the HpD-containing cell suspension were red-shifted and broadened as compared to those in the PBS solution. The degree of the polarization in the PBS and CTAC micellar solutions did not change with increasing incubation time, but in the cell suspension it increased temporarily and then decreased 4 h after incubation. These results suggest that HpD monomers and dimers may bind weakly to the outer cell membrane, and then slowly distribute throughout the intracellular loci in strong-binding form. In addition, the cellular uptake and/or binding loci of HpD were considered to be the mitochondria and nuclear membrane by subcellular fractionation and fluorescence microscopic studies.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00257181
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  • 6
    Electronic Resource
    Electronic Resource
    The effect of heat-treatment on the properties of activated carbon fibre cloth polarizable electrodes (1991)
    Springer
    Journal of applied electrochemistry 21 (1991), S. 28-31 
    Details
    ISSN: 1572-8838
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Electrical Engineering, Measurement and Control Technology
    Notes: Abstract The effect of heat-treatment on the properties of activated carbon fibre cloths (ACFC) as polarizable electrodes has been investigated. The heat-treated ACFC was prepared by heating phenolic resinbased activated carbon fibre cloths at temperatures higher than 1000° C in an inert gas atmosphere. The electrical resistance of ACFC and the specific surface area began to decrease at 1000° C and 1500° C, respectively. The ACFC maintained amorphous structure even when it was treated at 2000° C. The cyclic voltammogram of ACFC heat-treated at 1000° C showed a stable electric double layer in organic electrolytes in the range between−1.5 and 1.5V with respect to SCE. In accordance with the lower resistance of heat-treated ACFC, electric double layer capacitors with ACFC heat-treated at 1000° C showed lower d.c. resistance in comparison with capacitors without heat-treated ACFC.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01103825
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