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  • Articles  (66)
  • Microtubules  (37)
  • Chromatographie, Gas
  • Springer  (66)
  • 1980-1984  (66)
  • 1945-1949
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  • 1920-1924
  • 1981  (26)
  • 1980  (40)
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  • Articles  (66)
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  • Springer  (66)
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  • 1980-1984  (66)
  • 1945-1949
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  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Development genes and evolution 188 (1980), S. 65-73 
    ISSN: 1432-041X
    Keywords: Nuclear migration ; Cleavage ; Microtubules ; Ultrastructure ; Gall midge
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary In the eggs ofWachtliella persicariae the cleavage nuclei move relative to the surrounding ooplasm. This ‘active’ migration is caused by an organelle whose ultrastructure was studied throughout the mitotic cycle. It consists of a greatly enlarged polar cytaster derived from the mitotic apparatus, linked to the nucleus by 100 Å filaments. The microtubules of the cytaster were found only during periods of active nuclear migration, i.e., from the onset of anaphase to the early prophase of the next mitotic cycle. They are always solitary and follow the course of the astral rays, which are known to temporarily adhere to peripheral structures of the egg cell and to exert tractive forces. In contrast to the cytaster microtubules, the microtubules in the spindle are bundled and persist from early metaphase through late telophase. During ontogenesis the first migration cytaster is built up between 3 and 12 min after oviposition near the anterior egg pole, in the vicinity of the sperm nucleus. In non-inseminated eggs time lapse films show a migration cytaster to develop autonomously in a region free from nuclei, but it does not follow the normal path of the male pronucleus. In several cases the female pronucleus, which remains without a cytaster of its own, was observed to move to the cytaster generated in the absence of the male pronucleus. Whether or not it is adhering to a nucleus, the cytaster divides into two at the correct time, i.e, corresponding to the first cleavage division in fertilized eggs. In some non-inseminated eggs this type of ‘pseudocleavage’ has been observed to occur repeatedly, giving rise to an increasing number of anucleate cytasters.
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  • 2
    ISSN: 1432-2048
    Keywords: Cell walls ; Cellulose ; Graptopetalum ; Microtubules
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract In the “regeneration” of a shoot from a leaf of the succulent, Graptopetalum paraguayense E. Walther the first new organs are leaf primordia. The original arrangement of cellulose microfibrils and of microtubules (MTs) in the epidermis of the leaf-forming site is one of parallel, straight lines. In the new primordium both structures still have a congruent arrangement but it is roughly in the form of concentric circles that surround the new cylindrical organ. The regions which undergo the greatest shift in orientation (90°) were studied in detail. Departures from the original cellulose alignment are detected in changes in the polarized-light image. Departures from the original cortical MT arrangement are detected using electron microscopy. The over-all reorganization of the MT pattern is followed by the tally of MT profiles, the various regions being studied in two perpendicular planes of section. This corrects for the difference in efficiency in counting transverse versus longitudinal profiles of MTs. Reorientation takes place sporadically, cell by cell, for both the cellulose microfibrils and the MTs, indicating a coordinated reorientation of the two structures. That MTs and cellulose microfibrils reorient jointly in individual cells was shown by reconstruction of the arrays of cortical MTs in paradermal sections of individual cells whose recent change in the orientation of cellulose deposition had been detected with polarized light. Closeness of the two alignments was also indicated by images where the MT and microfibril alignments co-varied within a single cell. The change-over in alignment of the MTs appears to involve stages where arrays of contrasting orientation co-exist to give a criss-cross image. During this critical reorganization, the frequency of the MTs is high. It falls during subsequent enlargement of the organ. It was found that the rearrangement of the cortical MTs to approximate a series of concentric circles on the residual meristem occurred before the emergence of leaf primordia. Through their apparent influence on microfibril alignments, the changes in MT disposition, described here, have the potential to generate major biophysical changes that accompany organogenesis.
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  • 3
    ISSN: 1432-2048
    Keywords: Ca2+ transport ; Fungicides ; Herbicides ; Microtubules ; Mitochondria
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The herbicides amiprophosmethyl (APM) trifluralin, and oryzalin as well as the fungicides methylbenzimidazolyl carbamate (MBC), O-isopropyl N-phenyl carbamate (IPC), and chlorisopropyl N-phenyl carbamate (CIPC), which are known to cause the destruction of microtubules in vivo but do not interfere with tubulin polymerization in vitro, have been examined with respect to their ability to affect Ca2+ transport in isolated cell organelles. In contrast to colchicine which has no effect on Ca2+ transport in isolated mitochondrial and microsomal fractions, all of the substances investigated caused considerable reduction of ca2+ net uptake into mitochondrial but not into microsomal fractions. This reduction has been shown to be due to an increase in passive Ca2+ efflux. These results have been extrapolated to in vivo situations where they are postulated to act by raising cytoplasmic Ca2+ levels.
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  • 4
    ISSN: 1432-2048
    Keywords: Cell wall ; Microtubules ; Physcomitrella ; Polarity ; Protoplasts
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Protoplasts prepared from protonemal cultures of the moss Physcomitrella patens begin to regenerate a new cell wall within 1 h of removal from cellulase. The wall is seen as a gradually thickening mat of fibres when examined by scanning electron microscopy. Development of filaments from protoplasts takes place in the majority of cases only after one or more cell divisions have occurred. The direction of emergence of filaments is random in uniform light, but strongly negatively phototropic in bright unidirectional horizotal light. Filament growth is also strongly negatively phototropic. The influence of unidirectional light can be destroyed by incubating protoplasts in the presence of colchicine. Filaments growing in unidirectional light have cytoplasmic microtubules running along their long axes and in close association with large organelles. These results are discussed in terms of the potential for this system for the study of polarity in plants.
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  • 5
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    Planta 147 (1980), S. 405-413 
    ISSN: 1432-2048
    Keywords: Caulonema ; Cell growth (tip) ; Funaria ; Microtubules ; Organelle modification ; Polarity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract In the caulonema tip cells of Funaria hygrometrica, chloroplasts, mitochondria, and dictyosomes have differences in structure which are determined by cell polarity. In contrast to the slowly growing chloronema tip cells the apical cell of the caulonema contains a tip body. Colchicine stops tip growth; it causes the formation of subapical cell protrusions, redistribution of the plastids, and a loss of their polar differentiation. Cytochalasin B inhibits growth and affects the position of cell organelles. After treatment with ionophore A23 187, growth is slower and shorter and wider cells are formed. D2O causes a transient reversion of organelle distribution but premitotic nuclei are not dislocated. In some tip cells the reversion of polarity persists; they continue to grow with a new tip at their base. During centrifugation, colchicine has only a slight influence on the stability of organelle anchorage. The former polar organization of most cells is restored within a few hours after centrifugation, and the cells resume normal growth. In premitotic cells the nucleus and other organelles cannot be retransported, they often continue to grow with reversed polarity. Colchicine retards the redistribution of organelles generally and increases the number of cells that form a basal outgrowth. The interrelationship between the peripheral cytoplasm and the nucleus and the role of microtubules in maintaining and reestablishing cell polarity are discussed.
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  • 6
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    Planta 149 (1980), S. 389-401 
    ISSN: 1432-2048
    Keywords: Allium ; Cell wall Coated vesicles ; Guard cells ; Microtubules ; Protoplasts
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Protoplasts were prepared from the guard cells ofA. cepa. Epidermal peels taken from expanding green leaves and largely free of mesophyll were treated with Cellulysin, and protoplasts were harvested after 18 h of digestion. That the protoplasts were derived from guard cells was ascertained from their characteristic vacuolar autofluorescence and from observations showing that all other epidermal cells are killed in the peeling procedure. The protoplasts proved to be a good system with which to view the cell cortex and inner surface of the plasmalemma. The lysis of cells adhering to polylysine-treated, Formvar-coated grids, followed by negative staining in uranyl acetate, showed that many microtubules normally present in ordered arrays in situ remain closely applied to the inner surface of the plasmalemma in protoplasts. In addition, numerous vesiculate elements including coated vesicles and/or pits are present amongst the microtubules. Similar vesicles are evident in thin sections of fixed, embedded guard cells and protoplasts. The significance of these structures in the cell cortex is discussed.
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  • 7
    ISSN: 1432-2048
    Keywords: Cellulose microfibrils ; Graptopetalum ; Leaf formation ; Microtubules ; Organogenesis (biophysical theory) ; Polarity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Polarity shifts occur during organogenesis. The histological criterion for polarity is the direction of cell division. The biophysical criterion is the orientation of reinforcing cellulose microfibrils which lie normal to the organ axis and which determine the preferred growth direction. Using cell pattern to deduce cell lineage, and polarized light to study cellulose alignment, both aspects of polarity were examined in the epidermis of regenerating G. paraguayense. In this system new leaves and a stem arise from parallel cell files on a mature leaf. Large (90°) shifts in polarity occur in regions of the epidermis to give the new organs radial symmetry in the surface plane (files radiating from a pole). Study of the shifts in the epidermis showed that, during certain stages, shifts in the division direction are accompanied by shifts in the cellulose deposition direction, as expected. The new cellulose orientation is parallel to the new cross wall. During normal organ extension, however, shifts in division direction do not bring on changes in cellulose pattern. Thus the coupling between the two kinds of polarity is facultative. This variable relation is used in a biophysical model which can account for the reorganization of cell file pattern and cellulose reinforcement pattern into the radial symmetry of the new organ.
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  • 8
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    Planta 147 (1980), S. 500-506 
    ISSN: 1432-2048
    Keywords: Cell shape ; Colchicine ; Daucus ; Immunofluorescence ; Microtubules ; Protoplasts
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Indirect immunofluorescence has been used to study the function of cytoplasmic microtubules in controlling the shape of elongated carrot cells in culture. Using a purified wall-degrading preparation, the elongated cells are converted to spherical protoplasts and the transverse hoops of bundled microtubules are disorganised but not depolymerised in the process. Since microtubules remain attached to fragments of protoplast membrane adhering to coverslips and are still seen to be organised laterally in bundles, it would appear that re-orientation of the transverse bundles is due to loss of cell wall and not to the cleavage of microtubule bridges. After 24 h treatment in 10-3 M colchicine, microtubules are depolymerised in elongated cells but, at this time, the cells retain their elongated shape. This suggests that wall which was organised in the presence of transverse microtubule bundles can retain asymmetric shape for short periods in the absence of those tubules. However, after longer periods of time the cells become spherical in colchicine. Neither wall nor tubules therefore exert individual control on continued cellular elongation and so we emphasize the fundamental nature of wall/microtubule interactions in shape control. It is concluded that the observations are best explained by a model in which hooped bundles of microtubules—which are directly or indirectly associated with molecules involved with cellulose biosynthesis at the cell surface—act as an essential template or scaffolding for the orientated deposition of cellulose.
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  • 9
    ISSN: 1432-2048
    Keywords: Colchicine ; Membrane structure ; Microtubules ; Osmotic treatment ; Plasmalemma ; Poterioochromonas
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Changes in membrane topography in the flagellate Poterioochromonas malhamensis, as a result of colchicine and osmotic-stress treatments, have been studied using freeze-fracturing and thin sectioning. Ridges, but not rows of intramembrane particles, in the PF-face which denote the position of underlying cortical microtubules, together with the ridge associated with their point of origin (flagellar root fibre 1), dissappear after colchicine or short-term (5 min) osmotic treatments. Cortical microtubules are destroyed as a result of the former, but not the latter treatment. Longer periods in osmoticum allow a recovery of the microtubule — associated membrane ridges. Despite careful isosmotic fixations distinct cross-bridges between microtubules and the plasmalemma were not discernible in thin section.
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  • 10
    ISSN: 1432-072X
    Keywords: Protein ; RNA synthesis ; Microtubules ; Microfilament-disrupting drugs ; Heat ; Cold shock ; Recovery
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The effects of the microtubule-disrupting drugs, colchicine, vinblastine, podophyllotoxin, griseofulvin, and lumicolchicine (10-5 M), on protein and RNA synthesis were studied in Physarum polycephalum amoebae in culture. All, except lumicolchicine, were found to simultaneously reduce the rate of protein synthesis and stimulate RNA synthesis. These results parallel the effects seen in cells exposed to heat shock. Treatment of the cells with a microfilament-disrupting drug, cytochalasin B (10 μg/ml in ethanol), resulted in a reduced rate of protein synthesis after 2 h compared to a similar effect by vinblastine in 5–15 min. A morphological abnormality, microtubule paracystals, were seen associated with centrioles in vinblastine-treated cells in which protein synthesis had been reduced by 50%. Vinblastine and podophyllotoxin were shown to interfere with the recovery of protein synthesis after inhibition by low or elevated temperatures. The possible role of microtubules in regulating the translational response of a cell to an external environmental stimulus is discussed.
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  • 11
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    Fresenius' Zeitschrift für analytische Chemie 301 (1980), S. 108-109 
    ISSN: 1618-2650
    Keywords: Best. von Ethosuximid, Valproat in Blutserum ; Chromatographie, Gas
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Conclusion The proposed simultaneous determination of ethosuximide and valproate takes advantage of the similar properties of these substances that differ markedly from the other mainly used antiepileptic drugs. The volatility as well as the high blood concentration that are usual in therapeutics allow the measurement of ethosuximide and valproate directly in the extract without further concentration, e.g. by evaporation. On the other hand, one can optimise the methods for the determination of the other anticonvulsant drugs that are poorly volatile putting ethosuximide and valproate aside [1] and give up procedures using temperature programs with temperature differences of more than 100 ° C between the starting and the endpoint.
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  • 12
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    Cell & tissue research 208 (1980), S. 171-181 
    ISSN: 1432-0878
    Keywords: Microtubules ; Dendritic spine apparatus ; Synapse ; Development ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Using techniques for enhanced microtubular preservation, including albumin pretreatment (Gray, 1975), occipital cortex of rats was studied electron microscopically at various ages of development. A close structural relationship was seen between microtubules, sacs of SER and the postsynaptic “thickening” in primordial spines and with the dense “plate” material of spine apparatuses. Stereoscopic preparations in addition show a more complicated substructure than previously described for the “plate”. Microtubules may contribute to the formation of the “plate” of the spine apparatus which in turn is associated with the postsynaptic “thickening” of the mature spine. Possible functional correlates are discussed.
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  • 13
    ISSN: 1615-6102
    Keywords: Carteria ; Cell wall ; Cytokinesis ; Microtubules ; Papilla
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary An ultrastructural study of cytokinesis, cell wall ontogenesis, and papilla development/form inCarteria crucifera Korsh. andChloromonas rosae Ettl was undertaken. After typical phycoplast-mediated cytokinesis, wall ontogenesis begins at the level of Golgi apparatus activation and secretion to the outside of the daughter cells of fibrillar wall precursors which self assemble into the typical chlamydomonad wall (sensuRoberts 1974). As wall ontogenesis approaches the flagellar region of the cell, several precisely timed events occur: flagellar apparatus formation, flagellar emergence, protoplasmic extension in the future papilla area underlined by series of parallel aligned microtubules, wall formation (at least the W2–W6 layers), retraction of the protoplasmic extension and loss of underlying microtubules, and final wall modification (gap filling by W1 material) to yield the characteristic wall papilla. The transient cytoplasmic extensions mimic the shape of the future wall papilla and are maintained, at least inCarteria, by underlying microtubules. Structural and developmental properties of the papilla are characterized and phylogenetic implications are discussed.
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  • 14
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    Protoplasma 106 (1981), S. 273-287 
    ISSN: 1615-6102
    Keywords: Microtubules ; Polarity ; Spore development ; Trematodon
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Young spores of the mossTrematodon longicollis Mx. are highly polar. Immediately after meiotic cytokinesis an extensive system of microtubules associated with the single plastid develops under the entire distal face. Following exine initiation on the distal surface a microtubule system is elaborated at the site of aperture development on the proximal surface. Both plastid and nucleus move from distal to proximal pole and are attached to microtubules of the proximal system. Microtubules underlie the plasma membrane as it withdraws from the exine in the initiation of both the surrounding annulus and central aperture pore. The central pore enlarges to form a bowl-shaped concavity in which a fibrillar plug develops basipetally. The annulus expands into a fibrillar-filled protrusion surrounding the central pore. The mature aperture consists of a central pore plug covered by a thin roof of exine and separated from the surrounding annulus by exine lamellae. The aperture of the mature spore is obscured by development of the ornate exine and is not a prominent feature of the mature spore surface.
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  • 15
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    Protoplasma 108 (1981), S. 29-38 
    ISSN: 1615-6102
    Keywords: Ciliate ; Colpoda ; Cytoskeleton ; Hydrostatic pressure ; Microtubules
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The cytoskeletal function of cortical microtubular structures is explored by high-pressure treatment of the ciliated protozoonColpoda cucullus. This ciliate has two regions of form asymmetry which are apparently maintained by microtubules, namely the somatic groove and the right oral lip. Pressure induced changes in cellular morphology and motility were found to be a function of the magnitude of pressure and duration of compression. Cells exposed to 5,000 psi for 25 minutes, 7,500 psi for 12 minutes, and 10,000 psi for 3 minutes are quiescent and acquire a rounded shape. Observation by electron microscopy of cells exposed to 5,000 psi for 25 minutes indicates that the disappearance of the somatic groove and eversion of the oral apparatus are coincident with the disassembly of the microtubular rootlets in the groove and the supraepiplasmic microtubules in the right oral lip. Other changes accompanying the pressure-induced disassemblies include the reduction in numbers of overlapping microtubular ribbons in the cortical ridges and the appearance of cortical granular accumulations. The essential role in form-maintenance played by microtubular components is discussed.
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  • 16
    ISSN: 1615-6102
    Keywords: Cytokinesis ; Endoplasmic reticulum ; Funaria caulonema ; Microtubules ; Mitosis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The interphase nucleus in theFunaria caulonema tip cells is associated with many non-cortical microtubules (Mts). In prophase, the cortical Mts disappear in the nuclear region; in contrast to moss leaflets, a preprophase band of Mts is not formed in the caulonema. The Mts of the early spindle are associated with the fragments of the nuclear envelope. Remnants of the nucleolus remain in the form of granular bodies till interphase. The metaphase chromosomes have distinct kinetochores; the kinetochore Mts are intermingled with non-kinetochore Mts running closely along the chromatin. Each kinetochore is associated with an ER cisterna. ER cisternae also accompany the spindle fibers in metaphase and anaphase. In telophase, Golgi vesicles accumulate in the periphery of the developing cell plate where no Mts are found. The reorientation of the cell plate into an oblique position can be inhibited by colchicine. It is concluded that the ER participates in controlling the Mt system, perhaps via calcium ions (membrane-bound calcium ions have been visualized by staining with chlorotetracycline) but that, on the other hand, the Mt system also influences the distribution of the ER. The occurrence and function of the preprophase band of Mts is discussed.
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  • 17
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    Protoplasma 109 (1981), S. 143-157 
    ISSN: 1615-6102
    Keywords: Acetabularia ; Microfilaments ; Microtubules ; Protoplasmic streaming
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary A compilation of characteristics of the two different systems of intracellular transport inAcetabularia (Koop andKiermayer 1980 a and b) is given. The presence of microfilaments-presumably F-actin-in the cytoplasm ofAcetabularia is demonstrated by electron microscopy. The evidence for an involvement of microtubules in streaming is strengthened by the induction of birefringent vinblastine crystals in the stalk of vegetative cells. Isolated portions of cytoplasm formin vitro more than 100 μm long filopodium-like processes, which are highly birefringent. The processes show intensive immunofluorescent staining with both, anti-actin and anti-tubulin as a primary antibody. A perfusion buffer is presented, which after replacing the vacuolar sap does not lead to a change in cytoplasmic morphology or streaming pattern and velocities.
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  • 18
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    Protoplasma 109 (1981), S. 257-269 
    ISSN: 1615-6102
    Keywords: Acetabularia ; Dasycladalean green alga ; Flagellar roots ; Microtubules ; Striated fiber ; Phylogeny
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Ultrastructural investigation of the flagellar root system ofAcetabularia gametes reveals one type of organization for both male and female gametes. There is a modified cruciate system with four microtubular bands X-2-X-2, with X=4. A prominent distal striated fiber and a small proximal striated fiber connect the flagellar bases. A striated root fiber type I underlies the microtubular root type II, and a short striated root fiber type I underlies the microtubular root type I (terminology ofMelkonian 1980 b). This specific root system has some details in common with theChlamydomonas type, and others with theUlvaphyceae and the siphonalean algaeDerbesia andBryopsis. This might indicate the phylogenetic relationships.
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  • 19
    ISSN: 1615-6102
    Keywords: Cell polarity ; Differentiation ; Microtubules ; Nuclear migration ; Onoclea sensibilis ; Spore germination
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Germinating spores of the sensitive fern,Onoclea sensibilis L., undergo premitotic nuclear migration before a highly asymmetric cell division partitions each spore into a large protonemal cell and a small rhizoid initial. Nuclear movement and subsequent rhizoid formation were inhibited by the microtubule (MT) inhibitors, colchicine, isopropyl-N-3-chlorophenyl carbamate (CIPC) and griseofulvin. Colchicine prevented polar nuclear movement and cell division so that spores developed into enlarged, uninucleate single cells. CIPC and griseofulvin prevented nuclear migration, but not cell division, so that spores divided into daughter cells of approximately equal size. In colchicine-treated spores, MT were not observed at any time during germination. CIPC prevented MT formation at a time coincident with nuclear movement in the control and caused a disorientation of the spindle MT. Both colchicine and CIPC appeared to act at a time prior to the onset of normal nuclear movement. The effects of colchicine were reversible but those of CIPC were not. Cytochalasin b had no effect upon nuclear movement or rhizoid differentiation. These results suggests that MT mediate nuclear movement and that a highly asymmetric cell division is essential for rhizoid differentiation.
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  • 20
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    Protoplasma 102 (1980), S. 31-51 
    ISSN: 1615-6102
    Keywords: Microtubules ; Morphogenesis ; Cell Walls ; Roots ; Colchicine ; Cell division
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Removal and subsequent reformation of microtubules in cells of the root-tips ofAzolla pinnata R. Br. was achieved by short pulse treatments with the drug colchicine. Loss of microtubules led to the formation of multinucleate cells more frequently than to the arrest of mitosis at metaphase, and primary and secondary wall formation was also disrupted. Recovery of root development was limited. Growth of all roots ceased 5–6 days after the pulse treatment. Following the reappearance of microtubules, renewed deposition of normal wall thickenings occurred in developing xylem elements. Multinucleate cells became subdivided by walls in the apparent absence of a phragmoplast. The plane in which the new wall was formed was often located as it would have been in an untreated root, but in a number of cases abnormal or precious positioning of new walls was observed. Clusters of microtubules, matrix material, and vesicles or particles, taken to indicate microtubule initiation, were observed during the recovery from treatment.
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  • 21
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    Protoplasma 103 (1980), S. 105-114 
    ISSN: 1615-6102
    Keywords: Colchicine ; Lumicolchicine ; Microtubules ; Mitosis ; Wheat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Lumicolchicine was purified by preparative thin-layer chromatography. Tests for purity were ultraviolet absorption spectrophotometry, analytical thin-layer chromatography, and a bioassay using wheat roots. Wheat roots treated for 3 days with 10−3 M lumicolchicine showed no c-mitosis, but had reduced growth compared with controls.
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  • 22
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    Protoplasma 103 (1980), S. 205-229 
    ISSN: 1615-6102
    Keywords: Cell wall ; Cytochalasin B ; Microfibril orientation ; Microtubules
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Cortical microtubule arrays in the radish root hair were analyzed from reconstructions of serial ultra-thin sections in order to test extant hypotheses concerning the role of microtubules in the deposition of oriented microfibrils of cellulose. Passing away from the tip, root hairs exhibit a transition from random to oriented deposition of microfibrils at approximately 25 μm. Along the root hair, passing back from the tip, the microtubules: a) increase in number to a plateau at 25 μm; b) change their length profiles from approximately 60% less than 1 μm long in the hair tip to approximately 40% less than 1 μm long at 60 μm; c) maintain a constant pattern of angular deviation from the long axis, which is similar to the deviation pattern of the oriented wall fibrils; d) maintain a constant (approximately 70% of tubules) close (within 50 nm) proximity to the plasma membrane (PM); e) maintain a low (approximately 20%) degree of inter-microtubule proximity (i.e., within 50 nm of one another); f) show evidence for some variable long range (〉50 nm) association. Fixation with glutaraldehyde in a complete microtubule polymerization medium (MTPM), or pretreatment with cytochalasin B cause an approximate twofold increase in 1. the proportion of long microtubules in the tip region and 2. microtubules within 50 nm of one another. Fixation in incomplete MTPM (without GTP) produces results similar to phosphate buffer controls. Alternative explanations for these results are examined. A new hypothesis accounting for microtubule involvement in oriented microfibril deposition is described.
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  • 23
    ISSN: 1615-6102
    Keywords: Dikaryon ; Griseofulvin ; Microtubules ; Nuclear division ; Septal development ; Septal dissolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Ultrastructural study of a dikaryon of the basidiomyceteSchizophyllum commune showed that treatment with griseofulvin affected the site of the dividing nuclei and the location and structure of the septa. The microtubules were considered to be the primary target of griseofulvin, since they participate in nuclear division and movement in the hyphae, and their assembly is known to be in other organisms than fungi inhibited by griseofulvin. It is pointed out that dikaryotic hyphae with two nuclei and a clamp connection per cell are more sensitive indicators of the effect of griseofulvin than homokaryotic hyphae, whose structure is less complex.
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  • 24
    ISSN: 1615-6102
    Keywords: Cell wall ; Chytridiomycetes ; Chytridium confervae ; Cross-wall ; Microtubules ; Ribosomes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Chytridium confervae is a eucarpic, monocentric chytrid. We have used light and electron microscopy to study the relationship between the nutrient absorbing rhizoids and the asexually reproductive sporangium during growth. We have also examined the induction of zoosporogenesis by starvation, and subsequent differentiation until zoospore release. During growth the cytoplasm of the rhizoids and the developing sporangium was continuous and similar. At the start of starvation a bundle of fibers that were visible with light microscopy appeared at the junction between the rhizoids and the sporangium. Two hours after initiation of starvation a wall, that was also visible with light microscopy, formed to separate the rhizoids from the sporangium. Electron microscopy revealed a large, ordered array of microtubules in the thallus at the same time that the fibers appeared, and a sharp difference in the density of ribosomes in the cytoplasm of the sporangium and that of the rhizoids that was apparent immediately after starvation. This cytoplasmic difference was preserved by the formation of a cross-wall that was penetrated by plasmodesmata. After the wall was formed the cytoplasm of the rhizoids senesced. Comparison ofC. confervae with other organisms that use arrays of microtubules to move organelles is made and speculation on the role of the microtubules in organelle movement and wall formation inC. confervae is offered.
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  • 25
    ISSN: 1615-6102
    Keywords: Cell shape ; Chlorosarcinopsis ; Low temperature ; Microtubules
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The effect of low temperature (2 °C) on cell shape and microtubules in zoospores of the green algaChlorosarcinopsis gelatinosa has been investigated. The zoospores are 4–6 times longer than wide with a mean length of 12,5 μm and can be kept in the dark for several hours without changes in cell shape. Cell shape changes have been evaluated quantitatively by measuring changes in cell length. Low temperature induces a decrease in cell length which exhibits a two-step kinetic: during the first 30 minutes a rapid rate of decrease in cell length was measured, while during the next 4 hours a slow rate of decrease in cell length was observed. Complete regeneration of zoospore length occurs when cold-treated cells are subjected to the original zoospore induction temperature (30 °C) for two hours. Observation of numbers, disposition and types of microtubules in the zoospore during decrease in cell length has shown that within 30 minutes after cold application the secondary cytoskeletal microtubules (scmt) disappear, while flagellar root microtubules are unaffected. During this period most cells develop a prominent posterior appendage (tail). Sections demonstrate the presence of several microtubules in these tails. Flagellar root microtubules probably extend into the tails and disappearance of scmt starts at the posterior pole of the cell. Regeneration of zoospores to original cell length is coupled with reappearance of scmt starting at the anterior pole of the cell. It is concluded that secondary cytoskeletal microtubules constitute the main cytoskeleton inChlorosarcinopsis zoospores and that flagellar root microtubules contribute to only a minor extent to the cytoskeleton, because they cannot retain the cell shape. The results are discussed with respect to the functional significance of flagellar root microtubules in green algae.
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  • 26
    ISSN: 1615-6102
    Keywords: Immunofluorescence ; Microtubules ; Plant protoplasts ; Tobacco
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The arrangement of cortical microtubules in tobacco protoplasts is described using the following techniques: 1. Transmission electron microscopy (TEM) of thin sections of whole protoplasts, 2. TEM of negatively stained protoplast ghosts, and 3. Indirect immunofluorescence microscopy of protoplast ghosts. Ghosts were prepared by attaching freshly isolated protoplasts to glass coverslips or formvar/carbon-coated grids with poly-L-lysine and then bursting them either osmotically or by detergent treatment in the presence of a microtubule stabilizing buffer. Osmotic bursting of protoplasts yielded large pieces of plasma membrane with attached microtubules. These preparations proved very useful for measuring the density and length of cortical microtubules. Detergent treatment dissolved the plasma membrane and altered the distribution of cortical microtubules.
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  • 27
    ISSN: 1615-6102
    Keywords: Mebendazole ; Ascaridia ; Secretion ; Microtubules ; Anthelmintic
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The anthelmintic compound mebendazole caused the disappearance of microtubules in the intestinal cells ofAscaridia galli. Electron microscopy revealed that soon after the microtubules disappeared there was an accumulation of secretory vesicles near the golgi areas. subsequently many of these vesicles aggregated forming dense large vesicles near the terminal web of the intestinal cells. This provides further evidence for the involvement of microtubules in the secretion of products from eukaryotic cells. It seems likely that inhibition of microtubule directed secretory functions in various cell types is an important function in the anthelmintic activity of the benzimidazole carbamates.
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  • 28
    ISSN: 1615-6102
    Keywords: Desiccation damage ; DNA repair ; DNA replication ; Germination ; Membranes ; Microtubules ; Secale cereale L.
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Rye embryos of high viability and vigour can be imbibed for 1 hour, dehydrated and subsequently rehydrated without harm. However, extension of the imbibition period results in progressive structural damage to cells of both the embryonic root and the coleorhiza. Greatest sensitivity to this treatment is shown by the microtubule assembly system and the plasmalemma which loses its integrity permitting the egress of ribosomes and lipid towards the cell wall. Further stress results in fragmentation of the endoplasmic reticulum, disruption of plastid, mitochondrial and nuclear membranes and the dispersion of the contents of provacuoles. Damage is initiated during the drying of imbibed embryos but it is compounded by subsequent rehydration. Coleorhiza cells, particularly those distal to the root, which normally develop very rapidly during the early hours of germination are most sensitive to desiccation. The onset of sensitivity to desiccation (ca. 3 hours after imbibition) corresponds with a transitory halt in the increasing rate of protein synthesis and with the start of DNA replication. These results are discussed in relation to DNA repair and the “hardening” of seeds to stimulate rapid growth following rehydration.
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  • 29
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    Protoplasma 102 (1980), S. 295-306 
    ISSN: 1615-6102
    Keywords: Acetabularia ; Inhibitors ; Microcinematography ; Microfilaments ; Microtubules ; Protoplasmic streaming
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The sensitivity of the dual intracellular transport system inAcetabularia mediterranea (Koop andKiermayer 1979 a) to cytochalasin B (CB, 10−5 mol), chlorisopropyl-N-phenylcarbamate (CIPC, 2.10−4 mol), and amiprophosmethyl (APM, 3.10−5 mol) has been studied by microcinematography. Vegetative cells before cap formation, 2–3 cm in length, and cells with a maximum sized cap, containing secondary nuclei, were used for the experiments. All intracellular movements ceased under the influence of CB, while in contrast to “headed streaming bands” and to the migration of the secondary nuclei, the movement of chloroplasts at “thin filaments” was found to be insensitive to Col, CIPC, and APM. All inhibitory effects of the drugs on protoplasmic streaming were completely reversible within a time of less than 10–20 minutes recovery from the drugs. The results suggest an involvement of microfilaments in all intracellular movements while, in addition, microtubules seem to be connected with the movement on “headed streaming bands”, including the migration of secondary nuclei.
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  • 30
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    Cell & tissue research 206 (1980), S. 21-33 
    ISSN: 1432-0878
    Keywords: Chromatophores ; Light-sensitivity ; Alteration in cell shape ; Microtubules ; Echinoids
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Alterations in cell shape of the light-sensitive chromatophores of the sea urchin Centrostephanus longispinus were studied by scanning- and transmission electron microscopy. Transition of the aggregated to the dispersed state is accompanied by incorporation of vesicles into the membrane of the pigment cell. During dispersion a system of microtubules originating from centriole-like structures is established throughout the stellate cell. Within restricted areas of the cell, cytoplasmic differentiation and condensation is found. The possible functional significance of the findings is briefly discussed.
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  • 31
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    Cell & tissue research 206 (1980), S. 73-81 
    ISSN: 1432-0878
    Keywords: Exocrine pancreas (mouse) ; Electron microscopic autoradiography ; Microtubules ; Protein transport ; Vinblastine
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The effect of vinblastine on the intracellular transport of newly synthesized protein in the mouse exocrine pancreas in vivo was studied by electron microscopic autoradiography after administration of 3H-leucine. Vinblastine (1.1 μmole/mouse; i.v. injection) was in general given 1 h before radioleucine and 2–4 h before fixation of the pancreas by perfusion with glutaraldehyde. Vinblastine causes the disappearance of microtubules, mainly present in controls in the apical portion of the acinar cell. After injection of vinblastine, zymogen granules form clusters located throughout the cell but often associated with Golgi areas. The latter are enlarged mainly due to the accumulation of small vesicles. In addition, Golgi areas are displaced, most often in an apical direction. Electron microscopic autoradiography demonstrated that vinblastine delays the appearance of labeled protein in zymogen granules; even 2 h after injection of radioleucine the majority of silver grains is located over the rough endoplasmic reticulum while very few grains are related to zymogen granules. This finding might be related to the structural changes of the Golgi areas observed. Although intracellular migration of protein is retarded, zymogen granules are formed. However, many of the labeled granules are found in peculiar locations, often distant from the acinar lumen. The present study suggests that vinblastine, possibly due to its effect on microtubules, influences both the formation and the translocation of zymogen granules.
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  • 32
    ISSN: 1432-0878
    Keywords: Microtubules ; Colchicine ; Secretory vesicles ; Milk secretion
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Effect of colchicine on microtubules was studied in mammary epithelial cells treated both in vivo and in vitro with the alkaloid. Three hours after the intramammary infusion of colchicine, secretory activity of mammary epithelia ceased, milk constituents accumulated and were randomly distributed within the cytoplasm, sometimes leaking into the perialveolar connective tissue, and autophagic vacuoles were prevalent. It appeared that an accelerated involutionary process was occurring. No microtubules were observed after this treatment. In vitro treated cells appeared to be less affected by the alkaloid. Although numerous casein-containing secretory vesicles accumulated in the cytoplasm, lipid droplet accumulation was less, and fewer autophagic vacuoles were observed, although lysosomes were commonly observed. Occasionally, obliquely sectioned microtubules were found in cells treated with low concentrations of colchicine but were absent at higher colchicine concentrations; however, paracrystalline inclusions (tubulin aggregates) were observed in some cells at all concentrations of the drug. These observations provide evidence that drugs which interfere with microtubule integrity reduce the secretory activity in mammary epithelia. This evidence is consistent with the concept of an association of the microtubular system and the secretory process.
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  • 33
    ISSN: 1432-0878
    Keywords: Chondrocytes ; Golgi complex ; Microtubules ; Colchicine ; Metabolic inhibitors
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Previous work has shown that exposure of cultured chondrocytes to colchicine leads to disappearance of microtubules and dispersion of the dictyosomes of the Golgi complex throughout the cytoplasm. Here, the effects of cold and metabolic inhibitors on cultured chondrocytes have been investigated in order to characterize further the relationship between these organelle systems. After incubation of cells for 24 h at 4° C most, but not all microtubules disappeared, indicating the existence of cold-resistant microtubules. Dictyosomes remained united in one area, until transfer of cultures to 37° C, when they dispersed throughout the cytoplasm in about one-third of the cells. In cells exposed simultaneously to cold and colchicine, microtubules disappeared completely, but spreading of dictyosomes occurred only in some cells and became generalized first upon warming. Application of the metabolic inhibitors sodium azide or sodium fluoride (10-2 M) or 2-deoxyglucose (5×10-2 M) together with sodium cyanide (10-2 M) inhibited microtubule removal by colchicine. Consequently, spreading of the Golgi complex was prevented. These findings support the concept of an important role of microtubules in the organization of the Golgi complex. Moreover, depolymerization of microtubules by colchicine appears to be an energy dependent process.
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  • 34
    ISSN: 1432-0878
    Keywords: Anterior pituitary ; Microtubules ; Paracrystalline aggregates ; Ultrastructure ; Chinchilla
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Unusual paracrystalline aggregates of microtubules which have not been described in any other mammalian species were observed in cultured anterior pituitary cells of normal chinchillas as well as in situ in the pituitary glands of these animals. These aggregates appeared as regularly arranged tubular structures in the longitudinal plane, and as a checkerboard pattern of closely and regularly packed microtubules when examined in transverse section. Supplementation with vinblastine, colcemide or colchicine in the culture medium did not change these structures morphologically. Each unit of tubules consisted of an outer wall or parellelogram profile and an inner wall composed of a single hexagonal doublet or in a figure “8” form. The outer wall of the parallelogram was 35×28 nm in length for both sides, while the diagonal of the inner wall was 18×28 nm. These paracrystalline aggregates of microtubules in the chinchilla pituitary cells are morphologically distinct from the paracrystalline assembly of cytoplasmic microtubules induced by vinblastine or other alkaloids. The function and significance of these paracrystalline aggregates in anterior pituitary cells of the chinchilla are uncertain.
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  • 35
    ISSN: 1432-0878
    Keywords: Baboon pineal gland ; Microtubules ; Synaptic ribbons ; Circadian rhythm
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary In baboons kept under controlled lighting conditions, microtubules (MT) are readily seen in the perikaryal cytoplasm and in the perivascular processes of pinealocytes. A significant increase in the number of MT, single synaptic ribbons (SR) and the formation of synaptic ribbon fields (RF, i.e. organelles which consist of multiple dense rodlets or plates, and vesicles), occur during the dark phase of a circadian light-dark cycle. MT may act as “tracks” for the oriented flow of vesicles derived from the smooth endoplasmic reticulum, to cytoplasmic sites where RF are being formed. The origin of the dense rodlets of RF remains unknown. Structural differences between SR and RF indicate that the latter organelles are not directly involved in impulse propagation between adjacent baboon pinealocytes. RF may function as storage organelles for some of the pineal secretory products which are formed in large amounts during the dark phase.
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  • 36
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    Cell & tissue research 214 (1981), S. 323-341 
    ISSN: 1432-0878
    Keywords: Neurosecretory axons ; Actin filaments ; Microtubules ; Neurosecretory granules ; Microvesicles ; Coated vesicles
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The ultrastructural organization of actin filaments was studied in the neurohypophysial system of the rat after heavy meromyosin (HMM) labeling. This structural pattern is characterized by (1) a straight arrangement of the filaments parallel to the axonal axis in the proximal nondilated parts of axons, (2) a central location within axonal dilatations, and (3) a higher concentration within axonal endings where the filaments form a complex three-dimensional network. The relationships of the filaments to other axonal structures and organelles was further studied by use of electron microscopic stereoscopy. The actin filaments frequently appear anchored to the axolemma with either polar arrangements of the arrowhead decoration (i) at structurally undifferentiated sites, and (ii) more particularly within perivascular endings, at sites with electron-dense thickenings. In all axonal divisions actin filaments are also found to bind to filamentous material surrounding the microtubules and to various organelles. Within the terminal portions of the axons actin filaments exhibit close relationships to neurosecretory granules and to the numerous smooth microvesicles found in this region. Such preferential relationships are particularly observed both in axon terminals and in pituicytes, with coated vesicles frequently binding actin filaments. In water-deprived rats, the concentration of actin filaments is conspicuously increased along the axons and more clearly in the axonal swellings and endings, where they form a more complex and interconnected network. These data are discussed in the light of a possible involvement of contractile proteins in the mechanisms of axonal transport and terminal release of neurosecretory products.
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  • 37
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    Cell & tissue research 214 (1981), S. 397-405 
    ISSN: 1432-0878
    Keywords: Retinal pigment epithelium ; Brook trout ; Microtubules ; 10 nm-filaments
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Microtubules and 10 nm-filaments appear to be involved in the functions of the retinal pigment epithelium (RPE). The presence of microtubules in the RPE of light-adapted eyes, but not in dark-adapted eyes, suggests that they may be involved primarily in organelle movement. On the other hand, the random and constant presence of 10 nm-filaments within the basal portion of the PE implies a cytoskeletal role for these filaments.
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  • 38
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    Cell & tissue research 220 (1981), S. 787-795 
    ISSN: 1432-0878
    Keywords: Organ of CORTI ; Sensory cells ; Microtubules ; Synaptic transmitter
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The system of subsurface tubules in the outer sensory cells of the rat cochlea consists of tubules lying immediately beneath the cell membrane. The tubules extend from the region below the cuticular plate, follow without interruption along the contours of the cell membrane, and terminate as a complicated, branched system under the nucleus. Several mitochondria are found on the cytoplasmic side of the tubules. Microtubules are observed in the space between the subsurface tubules and the mitochondria, in contact with the membranes of the subsurface system and, rarely, in contact with small, stalked vesicles. Current theories on the role of the subsurface system are discussed and a new one, considering possible involvement of the system in transport of the synaptic transmitter, is proposed.
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  • 39
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    Fresenius' Zeitschrift für analytische Chemie 302 (1980), S. 264-268 
    ISSN: 1618-2650
    Keywords: Best. von Wasser in Organ. Lösungsmitteln ; Chromatographie, Gas ; ECD, 8–170 ppm
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Wasser ist in organischen Lösungsmitteln im ng-Bereich gas-chromatographisch ohne Derivatisierung mittels eines linearisierten Elektroneneinfangdetektors (ECD) nach Abtrennung auf einer Porapak QS-Säule bestimmbar. Ausreichend wasserfreie Lösungsmittel ließen sich durch Trocknen mit aktivierten 4 Å-Molekularsieben oder superaktiven Aluminiumoxiden W 200, Woelm Pharma, Eschwege, herstellen. Um Wasserblindwerte aus der Raumluft auszuschließen, ist es notwendig, sämtliche Operationen in einer Box mit Umlauftrocknung durchzuführen. Wassermengen bis zu 15 ng absolut sind bestimmbar. Im Konzentrationsbereich 7–150 μg/ml ist die Detektoranzeige für Wasser linear.
    Notes: Summary Water can be determined directly in organic solvents in the ng range after separation on a porapak-QS column using a linear electron-capture detector (ECD). Organic solvents can be dried by activated 4 Å molecular sieves to a water content of 5 μg/ml, about 0.3×10−3 molar. To exclude water contamination all operations, storage of solvents and standards included, were made in a glove box with permanent drying of the inside atmosphere. The EC-detector allows to determine 15 ng of water absolute. In the range of 7–150 μg/ml a linear response for water by the ECD has been found.
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  • 40
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    Fresenius' Zeitschrift für analytische Chemie 303 (1980), S. 20-22 
    ISSN: 1618-2650
    Keywords: Analyse von Biolog. Substanzen, Steroidhormonen ; Chromatographie, Gas ; Anreicherungsverfahren
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Summary A new technique for the quantitation of very low concentrations of biological substances by gas-liquid chromatography is described. It is based on the direct concentration of the substances to be measured at the inlet of the chromatographic column. This is accomplished by injection of the substance into the chromatographic apparatus, whose column is kept at the condensation temperature of the sample. Repeated injection in separate portions results in accumulation of the substance. Chromatography is readily achieved by heating to the optimal temperature. This technique yielded promising results in the quantitation of several steroid hormones.
    Notes: Zusammenfassung Das Verfahren beruht auf der direkten Konzentrierung der zu bestimmenden Substanzen am Eingang der chromatographischen Säule. Sie erfolgt durch Injektion der Substanzlösung in die Säule bei einer Temperatur niedriger als der Schmelzpunkt, so daß die Substanz nicht eluiert werden kann. Eine wiederholte Injektion einzelner Portionen führt zur Anreicherung der Substanz, die dann nach Erhöhung der Säulentemperatur chromatographiert werden kann. Das Verfahren wurde mit guten Ergebnissen zur Bestimmung einiger Steroidhormone angewendet.
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  • 41
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    Fresenius' Zeitschrift für analytische Chemie 300 (1980), S. 387-402 
    ISSN: 1618-2650
    Keywords: Best. von Hexachlorbenzol, Polychlorcamphenen, Toxaphen, Kohlenwasserstoffen, chlorierte in Biolog. Material ; Chromatographie, Gas ; Umweltbelastung
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Summary Fishes have been used to characterize pristine aquatic environments. In samples from a lake in the Tyrolian Alps (arctic char) and Northwest Ireland (pike), the Caspian Sea (sturgeon/Sevruga), the North Atlantic (salmon), the North Pacific (salmon) and the Antarctic Ocean at South Georgia (antarctic cod) hexachlorobenzene and polychlorinated camphene (PCC, Toxaphene) have been found. Samples are extracted by n-hexane/acetone (2+1), following a dimethylformamide/hexane clean-up of the lipid matrix. Adsorption chromatography on Florisil (1.25% water content) allows the elution of hexachlorobenzene, 4,4′-DDE and the polychlorobiphenyls (PCB) with n-hexane, while the mixture nhexane/diethyl ether (90+10) will elute the polychlorocamphenes (PCC) together with the hexachlorocyclohexane isomers and the DDT group. Identification of the PCC has been done by matching their retention indices measured by high resolution ECD glass capillary gas chromatography using the nalkyl-trichloroacetates as references and technical Toxaphene together with a slightly dehydrochlorinated product as authentic samples. The PCC content of the samples from the lakes in the European Alps and Northwest-Ireland, the North Pacific and the Antarctic Ocean was 125, 240, 285 and 68 ng of PCC per g of extractable lipids, respectively. The samples from the Caspian Sea and the North Atlantic had 1,625 and 3,500 ng of PCC per g of extractable lipids, respectively. All samples but the one from the Antarctic Ocean (liver) were spawn. Besides hexachlorobenzene and the PCC all samples contained polychlorobiphenyls (PCB), theα, β andγ-isomers of hexachlorocyclohexane, the compounds of the DDT-group and many other ECD-dectable not yet identified compounds.
    Notes: Zusammenfassung In Fischproben aus in erster Näherung unbelasteten Gebieten, dem Nordatlantik (Lachs), einem See in Nordwest-Irland (Hecht), einem Hochalpensee (Bergsaibling), dem Kaspischen Meer (Sternhausen), dem Nordpazifik (Lachs) und dem Antarktischen Ozean bei Südgeorgien (Antarktischer Dorsch) lassen sich Hexachlorbenzol und polychlorierte Camphene (PCC, Toxaphen®) nachweisen. Die Probe wird mit n-Hexan/Aceton (2+1) extrahiert. Die Lipide werden über eine Dimethylformamid/Hexan-Verteilung weitgehend abgetrennt. Adsorptions-Chromatographie an Florisil mit 1,25% Wassergehalt erlaubt die Elution von Hexachlorbenzol, 4,4′-DDE und der polychlorierten Biphenyle (PCB) mit n-Hexan; n-Hexan/Diethylether (90+10) eluiert die polychlorierten Camphene zusammen mit den Hexacyclohexan-Isomeren und der DDT-Gruppe. Die Identifizierung der PCC gelang über Vergleich der mit ECD-Capillar-Gas-Chromatographie unter Bezug auf die n-Alkyltrichloracetate gemessenen Retentionsindices. Als Standardsubstanz diente technisches Toxaphen, sowie ein durch methanolische KOH leicht dehydrochloriertes Produkt. Der PCC Gehalt lag bei den Proben aus dem Hochalpensee, einem See in Nordwest-Irland, dem Nordpazifik und dem Antarktischen Ozean bei 125, 240 bzw. 285 und 68 ng PCC/g extrahierbare Lipide. Die Proben aus dem Kaspischen Meer und dem Nordatlantik enthielten 1 625 bzw. 3 500 ng PCC/g extrahierbare Lipide. Bis auf die Probe aus der Antarktis (Leber) handelte es sich jeweils um Rogen. Neben dem Hexachlorbenzol und den Polychlorcamphenen wurden in allen Proben polychlorierte Biphenyle, dieα, β undγ-Isomeren des Hexachlorcyclohexans, die DDT-Gruppe und zahlreiche weitere bisher nicht identifizierte, mit dem ECD nachzuweisende Verbindungen gefunden.
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    Fresenius' Zeitschrift für analytische Chemie 302 (1980), S. 20-31 
    ISSN: 1618-2650
    Keywords: Analyse von Polychlorbiphenylen, Aroclor, Clophen ; Chromatographie, Gas ; Glascapillaren, Electron capture
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Summary The composition of seven technical PCB-mixtures (Aroclor [Monsanto, USA] und Clophen A [Bayer, FRG]) has been investigated by high-resolution thin-film glass capillary gas chromatography with electron-capture detector. Methylpolysiloxane (SE 30) and purified Apiezon L have been used as liquid phases. Identification of the single PCB components has been performed by comparison of their retention indices with those of polychlorinated biphenyls defined by synthesis or with values calculated from retention index increments. For marking the individual PCB compounds a systematic numbering has been used.
    Notes: Zusammenfassung Die Zusammensetzung sieben technischer Gemische polychlorierter Biphenyle (PCB) mit unterschiedlichem Chlorierungsgrad (Aroclor- [Monsanto, USA] und Clophen A- [Bayer, Bundesrepublik Deutschland]-Typen) wurde mit hochauflösender Gas-Chromatographie mit Elektroneneinfang-Detektion in Dünnfilm-Glascapillaren mit Methylpolysiloxan (SE 30) und gereinigtem Apiezon L als flüssiger Phase untersucht. Die Identifizierung der Einzelkomponenten erfolgte durch chromatographischen Vergleich mit definierten Referenzsubstanzen oder Vergleich der aus Inkrementen berechneten Retentionsindices. Für die Kennzeichnung der Einzelkomponenten wird eine systematische Numerierung entsprechend der Substituentenbezifferung verwendet.
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    Fresenius' Zeitschrift für analytische Chemie 304 (1980), S. 23-27 
    ISSN: 1618-2650
    Keywords: Best. von n-Butylzinnverbindungen in Luft ; Chromatographie, Gas
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung n-Butylzinnverbindungen (Tetra-, Tri-, Di-) wurden aus der angesaugten Luft an Chromosorb 102 adsorbiert, mit HCl-haltigem Diethylether desorbiert, falls nötig mit Methylmagnesiumchlorid umgesetzt und die methylierten Verbindungen gas-chromatographisch mit einem zinnspezifischen flammenphotometrischen Detektor bestimmt. Die mittlere Wiederfindungsrate (0,09–40 μg) von Bis(tri-n-butylzinn)oxid (TBTO) betrug: 93,3%; Streubereich der Einzelwerte ± 9,3% (P=95%, N=11). Wird 1 m3 Luft angesaugt, lassen sich noch Konzentrationen an n-Butylzinnverbindungen (Tetra-, Tri-, Di-) von 0,05 μg/m3 bestimmen. In einem mit einer TBTO-haltigen Dispersionsfarbe gestrichenen Raum wurde die Temperaturabhängigkeit der Tri-n-butylzinn-Konzentration in der Luft untersucht. Der Vergleich mit den Resultaten von Bestimmungen des Totalzinngehaltes läßt den Schluß zu, daß in der Luft nur Tri-n-butylzinnverbindungen vorlagen.
    Notes: Summary n-Butyltin compounds (tetra-, tri-, di-) have been adsorbed on Chromosorb 102 from the aspired air, desorbed with HCl-containing diethylether and, if necessary, converted to the corresponding methyl derivatives by reaction with methylmagnesium chloride. The derivatives were determined by GLC with a tin-specific flame photometric detector. The mean recovery (0.09–40 μg) of bis(tri-n-butyltin)oxide (TBTO) was 93.3%; tolerance limit ±9.3% (P=95%, N=11). With an air sample of 1 m3 it is possible to measure n-butyltin compounds (tetra-, tri-, di-) in concentrations down to 0.05 μg/m3. In a room coated with a TBTO-containing latex-based paint, the temperature dependence of the tri-n-butyltin concentration in the air has been studied. Comparison with results of total tin determinations allows the conclusion that the air contained only tri-n-butyltin compounds.
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    Fresenius' Zeitschrift für analytische Chemie 306 (1981), S. 183-189 
    ISSN: 1618-2650
    Keywords: Trenn. von Zirkonium u. Hafnium ; Chromatographie, Gas ; Tetrachloride
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Gas-chromatographische Trennungen der Tetrachloride von Zr und Hf an Kieselgel werden beschrieben. Durch Verwendung von Quarzsäulen mit kleinem Innendurchmesser gelingt eine wesentliche Erhöhung der Trennstufenzahlen. Apparative Verbesserungen gegenüber vorhergehenden Arbeiten werden aufgezeigt.
    Notes: Summary Gas-chromatographic separations of the tetrachlorides of Zr and Hf on silicagel are described. The use of quartz columns with small inner diameter results in a significant increase of plate numbers. Improvements of the equipments used in previous works are shown.
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    Fresenius' Zeitschrift für analytische Chemie 306 (1981), S. 323-339 
    ISSN: 1618-2650
    Keywords: Analyse von Organohalogenverbindungen in Fisch, Fischölen ; Chromatographie, Gas ; Glascapillar, Elektroneneinfang-Detektion, Nordatlantik
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Summary Fish and fish oils, which can be assigned to defined food webs, habitats and regions in the North Atlantic (Gulf Stream, Sargasso Sea, continental shelf of Iceland, Ireland, Norway, North Sea and Portugal) have been analyzed for organochloro compounds like hexachlorocyclohexane isomers (HCH), chloroterpene (toxaphen, polychlorocamphene), cyclodien pesticides (chlordane group, dieldrin), chlorobenzenes, chlorobiphenyls (PCB) and the DDT group. Phytoplancton feeding fish menhaden (Brevoortia tyrannus) were used to characterize the surface layer of the Atlantic west of the United States, while ground feeding predatory cod (Gadus morhua) and sea pike (Merluccius merluccius) should picture mainly the pollution near the continental shelf at 200–600 m depth. All groups of chemicals listed above could be found in the fish samples and in most cases the single components of mixtures (PCB, chlordane) could be identified by high resolution glass capillary gas chromatography with electron capture detection. Intensity and details of the pollution pattern vary strongly for the water regions investigated. The global water cycle and details of pollution input and history of water bodies can be used for an explanation.
    Notes: Zusammenfassung In Fischen, die einer bestimmten Nahrungskette und Region zuzuordnen sind (Bermuda, Kontinentalschelf westlich von Irland und Portugal) und in Dorschleberölen, die aus definierten Regionen des Nordatlantiks (Kontinentschelf von Island, Irland, Norwegen, Nordsee und Portugal) stammen, wurde die Belastung mit Hexachlorcyclohexanen (HCH), Chlorterpenen (Toxaphen), Cyclodien-Biociden (Chlordan-Gruppe, Dieldrin), Chlorbenzolen, Chlorbiphenylen (PCB) und der DDT-Gruppe bestimmt. Im Oberflächenwasser lebende Phytoplanktonfiltrierer [Menhaden (Brevoortia tyrannus)] wie auf dem Schelfsockel lebende bathypelagische Räuber [Dorsch, Kabeljau (Gadus morhua) und Seehecht (Merluccius merluccius)] sind untersucht worden. Damit ist der Eintrag sowohl nahezu unmittelbar aus dem Wasser (Phytoplanktonfiltrierer) wie über eine längere mittelbare und unmittelbare Nahrungskette (bathypelagische Räuber), erfaßt worden. Alle aufgeführten Substanzklassen konnten z. T. mit weitgehender Identifizierung der Einzelkomponenten durch hochauflösende Glas-Capillar-Gas-Chromatographie und Elektroneneinfang-Detektion nachgewiesen werden. Es zeigen sich deutliche regionale Unterschiede in der Stärke der Belastung und in dem Belastungsmuster. Die globale Wasserführung und der damit verbundene unterschiedliche Eintrag wie die unterschiedliche Historie der Wassermassen können als Erklärung herangezogen werden.
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    Fresenius' Zeitschrift für analytische Chemie 306 (1981), S. 397-398 
    ISSN: 1618-2650
    Keywords: Analyse von Dimethylterephthalat ; Chromatographie, Gas ; Rohester, Oxidationsgemisch, Trennflüssigkeiten
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    Fresenius' Zeitschrift für analytische Chemie 307 (1981), S. 1-6 
    ISSN: 1618-2650
    Keywords: Trenn. von polaren Verbindungen ; Chromatographie, Gas ; Glascapillarsäulen
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Es wird gezeigt, auf welche Weise Glascapillarsäulen für die Trennung freier polarer Verbindungen mit breitem Polaritätsbereich zu optimieren sind. Das Trennverhalten wird einmal durch eine irreversible Zerstörung des Phasenunterbaues und zum anderen durch reversible Veränderungen an der Phasenoberfläche negativ beeinflußt. Es wird ein Regenerationsverfahren mit alkoholischer Oxalsäurelösung beschrieben, das diese Einflüsse teilweise rückgängig macht.
    Notes: Summary A procedure is described for optimising the separation of free polar compounds with a large range of polarity by glass capillary columns. The separation is negatively influenced by irreversible destruction of the phase-base and reversible alteration of the phase surface. A regeneration method was developed for overcoming these effects partially by means of an alcoholic oxalic acid solution.
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    Fresenius' Zeitschrift für analytische Chemie 309 (1981), S. 370-372 
    ISSN: 1618-2650
    Keywords: Best. von Chrom ; Chromatographie, Gas ; PN-Detektor ; Acetylacetonchelate
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Die gas-chromatographische Bestimmung von Chrom als Chrom(III)-chelat mit Acetylaceton, Trifluoracetylaceton und Hexafluoracetylaceton als Komplexbildner wird beschrieben. Als Detektor findet der Phosphor-Stickstoff-Flammenionisationsdetektor Verwendung, der zwischen 0,1 und 100 ng linear anzeigt. Die Nachweisgrenze liegt bei 10−11 g.
    Notes: Summary The gas-chromatographic determination of chromium as Cr(III)-chelate with acetylacetone, trifluoroacetylacetone and hexafluoroacetylacetone as complexing agent is described. The phosphorusnitrogen flame-ionisation detector with a linear response between 0.1 and 100 ng is employed. Limits of detection are in the range of 10−11 g.
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    Fresenius' Zeitschrift für analytische Chemie 301 (1980), S. 143-143 
    ISSN: 1618-2650
    Keywords: Best. von Phenolen ; Chromatographie, Gas ; neue Methylierungsreagentien
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    Fresenius' Zeitschrift für analytische Chemie 301 (1980), S. 432-433 
    ISSN: 1618-2650
    Keywords: Analyse von Abwasser der Dimethylterephthalat-Produktion ; Chromatographie, Gas
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    Fresenius' Zeitschrift für analytische Chemie 303 (1980), S. 126-127 
    ISSN: 1618-2650
    Keywords: Analyse von Hydroxyfettsäuren ; Chromatographie, Gas ; ECD
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    Fresenius' Zeitschrift für analytische Chemie 303 (1980), S. 279-288 
    ISSN: 1618-2650
    Keywords: Analyse von Polysacchariden, Verdikkungsmitteln, Celluloseethern ; Chromatographie, Gas ; Zeisel-Spaltung
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Im vorliegenden zweiten Teil der dreiteiligen Übersicht zur Analytik der Polysaccharide wird am Beispiel einer Methylhydroxyethylcellulose (MHEC) die Erfassung der Celluloseether und -mischether mittels der Gas-Chromatographie vorgestellt. Dabei handelt es sich um die Beschreibung einer quantitativen Methode hoher Empfindlichkeit, die erforderlich ist, um Cellulosederivate mit geringer Mischsubstitution zu identifizieren und zu unterscheiden. Dazu werden die Celluloseether in einer speziell entwickelten Apparatur mit Iodwasserstoffsäure bei 140°C erhitzt. Von den sich bildenden Spaltprodukten werden die abdestillierten Alkyliodide in gekühltem Hexylbromid aufgefangen, gas-chromatographisch getrennt und identifiziert; gebildete Olefine werden durch Bromaddition erfaßt. Reproduzierbarkeit: ≤3% rel. Erfassungsgrenze: = 0,01% Hydroxyethylcellulose (HEC). Die Methode eignet sich auch zur Erfassung von Estern, S-Alkylgruppen, Methylimidverbindungen, Glykolanteilen oder bestimmten Tensiden.
    Notes: Summary In this second part of the three-part review on analysis of polysaccharides the characterization of cellulose ethers and cellulose mixed ethers by means of gaschromatography is described. The identification of the wide varying field of this cellulose ethers is presented using methylhydroxyethylcellulose (MHEC) as an example. To differentiate all cellulose mixed ethers, even those with little substitution of one of the two ether components, the method has to work qualitatively and quantitativly with a high sensitivity. The cellulose ethers are treated with hydriodic acid at 140°C in a special apparatus. The alkyliodides formed are distilled into cooled hexyl bromide. They are separated and identified by gaschromatography. Olefins also formed are determined by addition of bromine. Reproducibility: ≤ 3% rel. Limit of detection: = 0.01 % Hydroxyethylcellulose (HEC). This method can also be used for the determination of esters, S-alkyl groups, methylimides, glycols and some detergents.
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    Fresenius' Zeitschrift für analytische Chemie 303 (1980), S. 397-400 
    ISSN: 1618-2650
    Keywords: Best. von Benzo(a)-pyren in Erdölprodukten ; Chromatographie, Gas
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    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Summary A gas-liquid chromatographic method has been developed for the quantitive determination of benzo(a)-pyrene in petroleum products. At the 2 ppb benzo(a)pyrene level in a sample, the recovery is 87–90%. The detection limit is 50 ng. A column was employed with a liquid-crystal phase of bis(p-phenylbenzylidene)-bi-p-toluidine on Chromosorb.
    Notes: Zusammenfassung Das entwickelte gas-chromatographische Verfahren benutzt eine SÄule mit der Flüssig-Kristallphase von Bis(p-phenylbenzyliden)-bi-ptoluidin auf Chromosorb und gestattet im Bereich von 2 ppb Benzo(a)-pyren eine Wiederfindung von 87–90%. Die Nachweisgrenze liegt bei 50 ng.
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    Fresenius' Zeitschrift für analytische Chemie 301 (1980), S. 32-32 
    ISSN: 1618-2650
    Keywords: Best. von Hexachlorcyclohexan, Hexachlorbenzol in Boden ; Chromatographie, Gas ; Extraktion
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    Fresenius' Zeitschrift für analytische Chemie 304 (1980), S. 143-143 
    ISSN: 1618-2650
    Keywords: Best. von Hexachlorcyclohexan, Hexachlorbenzol im Wasser ; Chromatographie, Gas ; Extraktion
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    Fresenius' Zeitschrift für analytische Chemie 305 (1981), S. 193-195 
    ISSN: 1618-2650
    Keywords: Best. von Lindan, γ-Hexachlorcyclohexan in Spraydosen ; Chromatographie, Gas ; Electron capture
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    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Summary A method was developed for the determination of the lindane content of commercial household insecticide spray aerosols. After the propellant is removed from the chilled contents of the spray packages the hydrocarbon solution is analysed for its lindane content by electron-capture gas chromatography. Pure α-isomer of hexachlorocyclohexane serves as the internal standard. Experimental error is ± 5%.
    Notes: Zusammenfassung Das Treibmittel wird durch Ausfrieren abgetrennt und die Insecticidlösung gas-chromatographisch mit Electron-capture Detektor analysiert. Das reine α-Isomere dient als innerer Standard. Der Fehler beträgt ± 5%.
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    Fresenius' Zeitschrift für analytische Chemie 306 (1981), S. 401-402 
    ISSN: 1618-2650
    Keywords: Best. von Triazophos, Hostathion in Rapssamen ; Chromatographie, Gas ; Extraktion
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    Fresenius' Zeitschrift für analytische Chemie 307 (1981), S. 31-32 
    ISSN: 1618-2650
    Keywords: Best. von Clonazepam in Blutserum ; Chromatographie, Gas ; Aufbereitung, RP-18 Kleinsäulen
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    Fresenius' Zeitschrift für analytische Chemie 307 (1981), S. 286-287 
    ISSN: 1618-2650
    Keywords: Best. von Amsacrin in Plasma ; Chromatographie, Gas
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    Fresenius' Zeitschrift für analytische Chemie 309 (1981), S. 105-108 
    ISSN: 1618-2650
    Keywords: Trenn. von Vinca-Alkaloiden ; Chromatographie, Gas
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Summary A new GLC method was developed for the separation of vinca alkaloids. OV-101 stationary phase and programmed temperature analysis were used for the investigations. By this method the separation of closely related vinca alkaloids can be performed such as stereo and structural isomers, ester homologues of vincaminic and apovincaminic acids.
    Notes: Zusammenfassung Mit Hilfe von OV-101 als stationä-rer Phase und einem Temperaturprogramm (200–300° C, 5° C/min) konnten nahe verwandte Vinca-Alkaloide (Stereo- und Strukturisomere, Esterhomologe von Vincamin- und Apovincaminsäure) gas-chromatographisch getrennt werden.
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    Fresenius' Zeitschrift für analytische Chemie 302 (1980), S. 375-381 
    ISSN: 1618-2650
    Keywords: Best. von n-Alkanen, Pristan in Luft ; Chromatographie, Gas ; reine Luft
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    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Summary An analytical method was developed for measuring n-alkanes (C9 to C17) and other hydrocarbons in tropospheric air with mixing ratios of a few ppt (10−12) and higher. The hydrocarbons are collected in situ in absorption tubes, carefully protected against contamination and analysed later in the laboratory by gas chromatography. First data are reported for Atlantic air masses at the west coast of Ireland.
    Notes: Zusammenfassung Es wurde eine analytische Methode entwickelt zur Messung der n-Alkane (C9 bis C17) und anderer Kohlenwasserstoffe in reiner troposphärischer Luft mit Mischungsverhältnissen von einigen ppt (10−12) und aufwärts. Die Kohlenwasserstoffe wurden am Beobachtungsort angereichert, sorgfältig gegen Verunreinigung geschützt und später im Laboratorium gas-chromatographisch analysiert. Erste Daten für atlantische Luftmassen an der Westküste Irlands werden mitgeteilt.
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    Fresenius' Zeitschrift für analytische Chemie 302 (1980), S. 398-401 
    ISSN: 1618-2650
    Keywords: Best. von Wasserstoff in Magnesium ; Chromatographie, Gas ; Kapselmethode
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Summary A new method, the capsule method, has been developed for analyzing hydrogen in magnesium with a standard deviation of about 4%. 1–2 g samples are made with a smooth surface and enclosed in a degassed iron capsule. The surface humidity is removed by a short annealing at 400°C, and the sample is subsequently degassed at 500–620°C in vacuum. The extracted hydrogen is measured by gas chromatography. The commercial magnesium analyzed contained from 0.2 to 8 ppm of hydrogen. The diffusion coefficient of hydrogen was measured to be: D=D 0e−Q/RT; where D 0=9.5 · 10−6 m2/s and Q=46,400 Joule/mole. The results obtained were interpreted as interstitial diffusion of hydrogen in magnesium.
    Notes: Zusammenfassung Zur Analyse von Wasserstoff in Magnesium wurde eine neue Methode, die Kapselmethode, entwickelt, 1–2 g schwere Proben werden mit einer glatten Oberfläche hergestellt und in eine gasfreie Kapsel eingeschlossen. Die Oberflächenfeuchtigkeit wird durch kurzes Anlassen bei 400°C entfernt und die Probe wird danach bei 500–620°C im Vakuum entgast. Der entfernte Wasserstoff wird mit einem Gas-Chromatographen gemessen. Die Standardabweichung beträgt etwa 4%. Das untersuchte technische Magnesium enthält zwischen 0,2 und 8 ppm Wasserstoff. Der gemessene Diffusionskoeffizient für Wasserstoff ist: D=D 0e−Q/RT; D 0=9.5 · 10−6 m2/s und Q= 46400 Joule/Mol. Die erhaltenen Resultate wurden als interstitielle Wasserstoffdiffusion im Magnesium interpretiert.
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    Fresenius' Zeitschrift für analytische Chemie 303 (1980), S. 389-393 
    ISSN: 1618-2650
    Keywords: Best. von Chrom(III), Chrom(VI) in Wasser ; Chromatographie, Gas ; Extraktion
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    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Summary The gas-chromatographic determination of Cr(III) and Cr(VI) in aqueous solution using di(trifluoroethyl)dithiocarbamate as an extracting agent (pH 3) is described. Best results were obtained with a column of OV-25 (3% on Chromosorb HPW, 100–120 mesh, 160–210
    Notes: Zusammenfassung Die Extraktion mit dem Reagens wird bei pH 3 durchgeführt. Als SÄulenmaterial hat sich am besten OV-25 (3% auf Chromosorb HPW, 100–120 mesh, 160–210
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    Fresenius' Zeitschrift für analytische Chemie 304 (1980), S. 337-349 
    ISSN: 1618-2650
    Keywords: Analyse von Biphenylen, polychlorierten in Umweltmaterial ; Chromatographie, Gas ; Glascapillar
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    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Summary The PCB-pattern of biological environmental samples of different trophic levels (fish, bird, man) and geographic areas (Alps, North Sea, North Atlantic) as seen by high-resolution glass capillary gas chromatography with electron capture detection is presented. The most evident variation of the pattern compared to a best fit simulation by technical mixtures is found for warm blooded species (eggs of birds and human milk). Only one trichloro-, but nine tetrachloro-biphenyls and 55 penta-to octachloro-biphenyls have been identified as PCB-components in biological samples. Compounds with 4,4′-disubstitution degrade very slowly, if at all (1,4-recalcitrance principle). Single component analysis of PCB in marine samples using glass capillary gas chromatography needs the preseparation from the ubiquitous polychloroterpenes (toxaphene, polychlorocamphene) and the DDT-group. Both complex mixtures can be separated successfully by adsorption chromatography on Florisil. Quantitation of PCB as a sum has been done by using recalcitrant diagnostic components and PCB-Clophen A 60 as the reference standard.
    Notes: Zusammenfassung Die Bestimmung der Einzelkomponenten der polychlorierten Biphenyle (PCB) in Umweltproben durch Glascapillar-Gas-Chromatographie auf Methylsilicon- oder Apiezon L-Phasen erfordert eine Vortrennung von den Polychlorterpenen (Toxaphen, Polychlorcamphen) und der DDT-Gruppe. Diese Trennung gelingt durch Adsorptions-Chromatographie auf Florisil. Die PCB-Muster im Fett des phytoplanktonfressenden Seefisches Menhaden (Brevoortia tyrannus) aus dem Nordatlantik, im Rogen der zooplanktonfressenden Salmoniden Seesaibling (Salvelinus alpinus) und Bachforelle (Salmo trutta m. fario) aus Bergseen in Tirol, und in der Leber der Süßwasserdorschart Quappe (Lota lota) aus dem Bodensee werden gezeigt. Die stärksten Veränderungen gegenüber einer aus technischen Gemischen hergestellten Simulationsmischung werden für Warmblütlerproben — Eier von Brandgans (Tadorna tadorna) und Küsten-Seeschwalbe (Sterna paradisea); Humanmilch — gefunden. Neben einem Trichlor- und neun Tetrachlorbiphenylen wurden 55 Pentabis Octachlorbiphenyle nachgewiesen. Komponenten mit einer 4 und/oder 3,5-Substitution in beiden Ringen werden beträchtlich langsamer abgebaut als anders strukturierte Komponenten (1,4-Rekalzitranz-Prinzip). Die Quantifizierung der PCB als Summe erfolgte über schwer abbaubare, signifikante Hauptkomponenten unter Verwendung eines Clophen A 60 PCB-Gemisches als Eichstandard.
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    Fresenius' Zeitschrift für analytische Chemie 306 (1981), S. 190-195 
    ISSN: 1618-2650
    Keywords: Best. von Nitrat, Sulfat, Phosphat in Wasser ; Chromatographie, Gas ; Regen u. Flußwasser, Vergleichsanalysen
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Eine neue Methode zur gas-chromatographischen Bestimmung anorganischer Anionen wird vorgestellt. Sie eignet sich zur Analyse wäßriger Lösungen (Regenwasser, Flußwasser) auf Nitrat, Sulfat und Phosphat. Anreicherung und Derivatisierung werden durch Gefriertrocknung der Silbersalze und deren Umsetzung mit n-Butyliodid zu den n-Butylestern erreicht. Bei Einsatz von 10 ml Probe liegen die niedrigsten Eichwerte bei 2·10−6 M (Nitrat), 1·10−6 M (Sulfat) und 3·10−7 M (Phosphat). Das neue Verfahren wurde durch Vergleichsmessungen mit jeweils zwei unabhängigen Methoden überprüft (Ionen-Chromatographie und Photometrie für Nitrat und Phosphat, Ionen-Chromatographie und Isotopenverdünnungsanalyse für Sulfat).
    Notes: Summary A new method for the gas-chromatographic determination of inorganic anions is presented. It is suitable for the analysis of samples such as rain and surface waters for nitrate, sulphate, and phosphate. Preconcentration and derivatisation are achieved by freeze-drying the corresponding silver salts and converting them into the n-butyl esters using n-butyl iodide. Employing 10 ml of sample for analysis, the lowest calibration values were 2·10−6 M, 1·10−6 M, and 3·10−7 M for nitrate, sulphate, and phosphate, respectively. The reliability of the new procedure was evaluated by comparison measurements using two independent methods for each ion (ion chromatography and photometry for nitrate and phosphate, ion chromatography and isotope dilution analysis for sulphate).
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    Electronic Resource
    Springer
    Fresenius' Zeitschrift für analytische Chemie 309 (1981), S. 1-7 
    ISSN: 1618-2650
    Keywords: Analyse von Organohalogenverbindungen in Pinguineiern ; Chromatographie, Gas ; Glascapillar-, Elektroneneinfang-Detektion
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Summary Eggs of penguins can be used to monitor indirectly the pollution of the antarctic and sub-antarctic marine environment. The different penguin species are located in defined circumpolar areas, allowing an easy regional monitoring of persistent xenobiotics in the Antarctic. In eggs from the Gentoo penguin (Pygoscelis papua), the Rockhopper penguin (Eudyptes crestatus) and the Magellanic penguin (Spheniscus magellanicus) collected 1978 at the Falkland Islands the following xenobiotics could be detected after preseparation by liquid chromatography on Florisil and high resolution glass capillary gas chromatography with electron capture detection: alpha and gamma hexachlorocyclohexane, hexachlorobenzene, polychlorobiphenyls, 2,4′-DDT, 4,4′-DDT, 4,4′-DDE, 4,4′-DDD, mirex, polychloroterpenes and further not yet identified xenobiotics. In eggs of the Black-browed albatros (Diomedea melanophris) compounds of technical chlordane could be detected as well. In eggs of the vegetarian Kelp goose (Chloephaga hybrida) only traces of hexachlorobenzene and 4,4′-DDE could be detected.
    Notes: Zusammenfassung In Eiern von Pinguinen kann indirekt die marine Belastung der Antarktis und Sub-Antarktis nachgewiesen werden. Da die verschiedenen Pinguinarten circumpolar bestimmten geographischen Bereichen zugeordnet werden können, ist auf einfache Weise eine regionale Bestandsaufnahme der persistenten Umweltchemikalien in der Antarktis möglich. In Eiern vom Eselspinguin (Pygoscelis papua), Felsenpinguin (Eudyptes crestatus) und Magellanpinguin (Spheniscus magellanicus) von den Falkland-Inseln lassen sich nach hochauflösender Capillar-Gas-Chromatographie und Vortrennung auf Florisil nachweisen: α-, und γ-Hexachlorcyclohexan, Hexachlor-benzol, Polychlorbiphenyle, 2,4′-DDT, 4,4′-DDT, 4,4′-DDE, 4,4′-DDD, Polychlorterpene, Mirex und weitere bisher nicht identifizierte Verbindungen mit ECD-Anzeige. Im Ei des Schwarzbrauenalbatros (Diomedea melanophris) waren zusätzlich Komponenten des technischen Chlordans nachweisbar. Im Ei der Tangfressenden Kelpgans (Chloephaga hybrida) waren nur Spuren von Hexachlorbenzol und 4,4′-DDE zu identifizieren.
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