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1980 (201)
181Author    E. Lopez Cabarcos, S. Fernandez Bermudez, F.J Baltá CallejaRequires cookie*
 Title    The Paracrystalline Nature of the Purple Membrane of Halobacterium halobium I. Lattice Distortions within the Membrane  
 Abstract    Purple Membrane o f Halobacterium halobium, X-Ray Diffraction, Paracrystalline Distortions, Crystal Size X-Ray diffraction patterns from oriented purple membrane of Halobacterium halobium show that the packing o f proteins within the membrane has a paracrystalline structure. The paracrys­ talline mean distance fluctuations, g, were found to be 1.5 (± 0.1)% for the (100) packing planes of the proteins. The corresponding paracrystallite sizes are of ~ 850 A. It is suggested that para­ crystalline lattice distortions within the membrane may be explained by conformational singu­ larities of the proteins or by an irregular packing o f adjacent proteins and lipids. 
  Reference    Z. Naturforsch. 35c, 1032—1035 (1980); received June 23 1980 
  Published    1980 
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 TEI-XML for    default:Reihe_C/35/ZNC-1980-35c-1032.pdf 
 Identifier    ZNC-1980-35c-1032 
 Volume    35 
182Author    D. Schneider, D. FalkeRequires cookie*
 Title    Investigations on the Mechanism of Induction of the Alkaline Phosphatase by Bromodesoxyuridine in Herpes simplex Virus Transformed Cells and the Transport of Uridine  
 Abstract    Addition o f BrdUrd in combination with prednisolone to HSVj-transformed hamster embryo cells induces an alkaline phosphatase (AP). FdUrd enhances, dThd reduces the inducing capacity of BrdUrd and prednisolone. Induction is prevented by addition of cycloheximide or o f cytosine arabinoside. BrdUrd reduces transport and phosphorylation o f exogenously applied labeled Urd, especially the amount of UTP, UDP and Urd-diphosphate sugars. The Lineweaver-Burk-plot o f uridine-up-take after addition of BrdUrd reveales the characteristics o f the mixed type inhibition (competi­ tive-noncompetitive). 
  Reference    Z. Naturforsch. 35c, 1036—1045 (1980); received July 22 1980 
  Published    1980 
  Keywords    Alkaline Phosphatasel, HSVj-Transformed Hamster Tumor Cells, Induction by BrdUrd and Prednisolone, Urd-Transport 
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 TEI-XML for    default:Reihe_C/35/ZNC-1980-35c-1036.pdf 
 Identifier    ZNC-1980-35c-1036 
 Volume    35 
183Author    Jürgen KreftRequires cookie*
 Title    Reovirus-Specific Messenger Ribonucleoprotein Particles from Heia Cells  
 Abstract    When reovirus-infected Heia cells are incubated at 43 °C virus-specific messenger RNA is released from the polysomes. It accumulates free in the cytoplasm as messenger ribonucleopro­ tein particles (mRNPs). These particles have a sedimentation rate of about 50 S and a buoyant density in CsCl of 1.42 g/cm 3. Reovirus mRNPs contain, besides all three size classes o f reovirus messenger RNA, the same spectrum of proteins found in the polysomal mRNPs from uninfected cells, plus two additional proteins with molecular masses of 70000 d and 110000 d, respectively. Electron microscopic examination of the reovirus structures with a total mean length of 0.5 nm. 
  Reference    Z. Naturforsch. 35c, 1046—1051 (1980); received May 14/August 13 1980 
  Published    1980 
  Keywords    Heia Cells, Reovirus, Messenger Ribonucleoprotein Particles, mRNP-Proteins, Electron Microscopy 
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 TEI-XML for    default:Reihe_C/35/ZNC-1980-35c-1046.pdf 
 Identifier    ZNC-1980-35c-1046 
 Volume    35 
184Author    I. F. Kaetsu, T. Yoshii, FujimuraRequires cookie*
 Title    Effect of Viscous Solvents and Monomer on Conservation of Intact and Immobilized Chloroplasts  
 Abstract    0 2 evolution activity of PS II in chloroplast stored in buffer including various supercooling solvents was studied. Viscous solvents such as polyethylene glycol (PEG) was remarkably effective for the increase o f lifetime o f intact chloroplast. Lifetime of immobilized chloroplast by means of radiation polymerization was prolonged more than 40 days in buffer including PEG 70% (v/v). It was found that viscous solvents having PEG units in molecular chain were effective and methoxypolyethyleneglycol methacrylate monomer (M-23G) was most suitable as a im­ mobilization carrier. The immobilized chloroplast with M-23G retained the high activity yield more than 30 days in buffer including PEG. 
  Reference    Z. Naturforsch. 35c, 1052—1056 (1980); received September 2 1980 
  Published    1980 
  Keywords    Chloroplast, Immobilization, Oxygen Evolution, Viscous Solvent, Radiation Polymerization 
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 TEI-XML for    default:Reihe_C/35/ZNC-1980-35c-1052.pdf 
 Identifier    ZNC-1980-35c-1052 
 Volume    35 
185Author    AlanC. Cassells, FrancesM. CockerRequires cookie*
 Title    TMV Inoculation of Tobacco Protoplasts in the Presence of Protoplast Fusion Agents  
 Abstract    Two methods used to induce protoplast fusion, involving polyethylene glycol (PEG) and high calcium/high pH, respectively, have been investigated in procedures for the inoculation of isolated tobacco protoplasts with TMV. It has been shown that inoculation in the presence of fusion agents involves two stages. Firstly, virus precipitation on to the protoplast surface and secondly, entrapment of virus particles between protoplasts in zones (putatively) o f transient protoplast fusion. 
  Reference    Z. Naturforsch. 35c, 1057—1061 (1980); received June 24/August 22 1980 
  Published    1980 
  Keywords    Polyethylene Glycol, Protoplasts, Tobacco Mosaic Virus 
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 TEI-XML for    default:Reihe_C/35/ZNC-1980-35c-1057.pdf 
 Identifier    ZNC-1980-35c-1057 
 Volume    35 
186Author    Rolando Tijerina, Jürgen Löhler, UmeshC. Chaturvedi, Fritz Lehmann-GrubeRequires cookie*
 Title    Infection of Murine T Lymphocytes with Lymphocytic Choriomeningitis Virus: Effect of Age of Mice on Susceptibility  
 Abstract    T lymphocytes were determined in thymuses and spleens of mice acutely infected with LCM virus. Such cells appeared in newborn animals, but their numbers declined when the age at infection increased and none were found in adult mice. Either susceptibility to LCM virus is associated with some degree of immaturity or the probability of murine T lymphocytes to encounter the virus as an infectious entity rather than an immunogen is higher in very young than in immunologically mature mice. 
  Reference    Z. Naturforsch. 35c, 1062—1065 (1980); received July 311980 
  Published    1980 
  Keywords    Lymphocytic Choriomeningitis Virus, LCM Virus, T Lymphocytes, Persistent Infection, Immunological Tolerance Infectious 
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 TEI-XML for    default:Reihe_C/35/ZNC-1980-35c-1062.pdf 
 Identifier    ZNC-1980-35c-1062 
 Volume    35 
187Author    Jean-Paul Delbecque, Karel SlámaRequires cookie*
 Title    Ecdysteroid Titres during Autonomous Metamorphosis in a Dermestid Beetle  
 Abstract    The larvae of Dermestes maculatus are able to undergo several moults in complete absence o f the cephalic and prothoracic neuroendocrine system, showing thus spontaneous metamorphosis. Measurements of ecdysteroid contents by radioimmunoassay methods have revealed distinctive larval, prepupal and pupal ecdysteroid peaks, as found in other species where development requires frequent stimulation by the centrally produced hormones. Mass fragmentographic analysis has indicated that more than 80% of the ecdysteroids detected by the radioimmunoassay during the peaks consists of ecdysterone. The prothoracic glands (PG) o f D. maculatus larvae are located in the head capsule and in the cervical region. They can be separated from the body by neck-ligation. Only the larval peak o f ecdysterone can be correlated with PG function. The prepupal and pupal peaks o f ecdysterone are not produced by the central neuroendocrine system. The isolated abdominal fragments o f larvae and pupae positively produce ecdysteroids in the course of their independent development, but this synthesis has been subnormal and occasionally delayed in time. In contrast, the isolated thoracic fragments produce well synchronized peaks o f ecdysterone and this does not depend on the PG. It thus appears that some thoracic tissue other than PG is able to maintain the physiological concentration o f ecdysterone by means o f a concentration-dependent feed-back mechanism. Due to spontaneous metamorphosis and extremely good survival we have succeeded to induce in this species: a) premature formation o f the prepupal cycle of ecdysterone synthesis in the penultimate larval instar by ligation; b) inhibition and delay o f the prepupal peak by means of juvenoid treatments; c) reappearance o f the prepupal peak in the inhibited "permanent larvae" by exogenous administration of ecdysterone, or; d) modification of the pupal peak by a qualitatively new pupal-pupal one after juvenoid treatments. These experimental transformations o f the ecdysterone peaks have suggested that the kind and nature o f the peaks are closely related to nature and stage o f the ontogenetic development. We therefore believe that the process o f larval-pupal reprogramming has occurred in this species long before the increase o f ecdysterone titer in the body. Both the prepupal and pupal peaks do not represent a cause but they show to be rather consequences o f the developmental programming. Further features associated with possible physiological role o f ecdysteroids in insect development have been briefly discussed. 
  Reference    Z. Naturforsch. 35c, 1066—1080 (1980); received June 19 1980 
  Published    1980 
  Keywords    Ecdysteroids, Juvenile Hormone, Metamorphosis, Dermestes maculatus 
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 TEI-XML for    default:Reihe_C/35/ZNC-1980-35c-1066.pdf 
 Identifier    ZNC-1980-35c-1066 
 Volume    35 
188Author    Peter Scheurich, Ulrich Zimmermann, Maja Mischel, Ingolf LamprechtRequires cookie*
 Title    Membrane Fusion and Deformation of Red Blood Cells by Electric Fields  
 Abstract    Human red blood cells suspended in a slightly hypotonic solution o f low electric conductivity were exposed to an inhomogeneous and alternating electric field (sine wave, 30 V peak-to-peak value, electrode distance 120 |im, 0.5 to 2 MHz). Due to the dielectrophoretic effect the cells align parallel to the field lines under the formation o f pearl chains. At high voltages (10 V amplitude) membrane fusion is observed between the adhered red blood cells in the pearl chains, whereby the chains become attached to the electrodes. In contrast to the pearl chains observed at voltages o f up to 5 V amplitude the resulting fused and uniform aggregates which exhibit no recognisable individual cells under the light microscope, remain stable, even after the alternating electric field has been switched off or after haemolysis in response to osmotic shock. The fused aggregates are highly elastic. If the field strength o f the applied alternating electric field is further increased they are stretched in the direction o f the opposite electrode. Frequently, bridges are formed between the two electrodes. The uniform bridges remain stable for some time even in the absence o f an electric field. The possibility o f cell fusion and its initiation by electrical breakdown of the cell membranes are discussed. 
  Reference    Z. Naturforsch. 35c, 1081—1085 (1980); received August 21 1980 
  Published    1980 
  Keywords    Deformability, Dielectrophoresis, Electric Breakdown, Erythrocytes, Fusion 
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 TEI-XML for    default:Reihe_C/35/ZNC-1980-35c-1081.pdf 
 Identifier    ZNC-1980-35c-1081 
 Volume    35 
189Author    Hans MeinhardtRequires cookie*
 Title    Cooperation of Compartments for the Generation of Positional Information  
 Abstract    A mechanism is proposed for pattern formation in developmental subfields. In application to imaginal disks, the compartmentalization appears as a prerequisite for the generation of posi­ tional information in the proximo-distal dimension. Cooperation of three or four compartments in the production of a morphogen leads to a cone-shaped morphogen distribution, since a high production rate of the morphogen is possible only at the intersection of compartment borders. The local concentration of the cone-shaped distribution is a measure for the distance from this center and can be used as positional information. In agreement with the experimental observa­ tions, the model predicts that (i) the distalmost structures are formed at the intersection of compartment borders; (ii) distal transformation occurs whenever cells of all compartments come close to each other; (iii) distal transformation does not require a complete set of circumferential structures; (iv) mutants exist in which the positional information and not the response of the cells is altered and (v) no distal to proximal intercalation of missing leg segments occur. Regeneration and formation of supernumerary insect legs can be explained as well. Simple molecular reaction can account for this type of pattern formation. The "complete circle rule" of French, Bryant and Bryant (Science 193,969-981 (1976)) for distal transformation may be simplified by a "coopera­ tion of compartments" rule. 
  Reference    Z. Naturforsch. 35c, 1086—1091 (1980); received July 21 1980 
  Published    1980 
  Keywords    Positional Information, Imaginal Disk, Compartments, Pattern Formation 
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 TEI-XML for    default:Reihe_C/35/ZNC-1980-35c-1086.pdf 
 Identifier    ZNC-1980-35c-1086 
 Volume    35 
190Author    J. C. Stockert, A. JuarranzRequires cookie*
 Title    Temperature-Dependent Staining Reaction of Chromatin by Alcian Blue  
 Abstract    Alcian Blue, Staining Mechanism, C hrom atin Cytochem i­ stry After treatm ent with Alcian blue at high tem peratures, nuclei from chicken blood smears showed an intense stai­ ning rection, which proved to be dependent on the DNA content of chromatin. The possibility that interactions bet­ ween the phthalocyanine chrom ophore and unpaired bases accounts for this tem perature-dependent staining o f chro­ matin is briefly discussed. 
  Reference    Z. Naturforsch. 35c, 1092—1093 (1980); received August 111980 
  Published    1980 
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 TEI-XML for    default:Reihe_C/35/ZNC-1980-35c-1092_n.pdf 
 Identifier    ZNC-1980-35c-1092_n 
 Volume    35 
191Author    Rüdiger RiehlRequires cookie*
 Title    Pomatoschistus minutus III. Determination of Amino Acid Component  
 Abstract    The oocytes of the marine goby Pomatoschistus minutus were analyzed for their amino acid content. Most of the amino acids exist as protein, only a little part is free or peptide-bound. Among the protein-bound amino acids, high levels of glutamic acid, proline, alanine, aspartic acid, valine and leucine were detected. These represent more than 60% of the protein amino acids. Among the free acids, glutamic acid, serine and alanine, are dominant. There are no certain proofs o f the occurrence o f peptide pools in the oocytes o f Pomatoschistus minutus. 
  Reference    Z. Naturforsch. 35c, 1094—1095 (1980); received June 9/July 16 1980 
  Published    1980 
  Keywords    Oocytes, Yolk, Amino Acid Component, Pomatoschistus minutus, Teleost 
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 TEI-XML for    default:Reihe_C/35/ZNC-1980-35c-1094_n.pdf 
 Identifier    ZNC-1980-35c-1094_n 
 Volume    35 
192Author    Rudolf Hänsel, R. Ainer, W. Ohlfart, Helm Ut CoperRequires cookie*
 Title    Narcotic Action of 2-M ethyl-3-butene-2-ol Contained in the Exhalation o f Hops  
  Reference    Z. Naturforsch. 35c, 1096—1097 (1980); eingegangen am 7. Juli 1980 
  Published    1980 
  Keywords    Humulus lupulus (Cannabaceae), 2-Methyl-3-butene-2-ol, Narcotic Principles o f Hops 
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 TEI-XML for    default:Reihe_C/35/ZNC-1980-35c-1096_n.pdf 
 Identifier    ZNC-1980-35c-1096_n 
 Volume    35 
193Author    Isabel Garcia, Blanca Cifuentes, Carlos VicenteRequires cookie*
 Title    LrUsnate-Urease Interactions: Binding Sites for the Ligand  
 Abstract    L-usnic acid inactivates urease by formation o f high molecular weight aggregates which can reached by a maximum of 880 000. L-cysteine partially reverses the inactivation by stimulating the appearance of active high molecular weight polymers. The existence of two class of binding points for L-usnic acid on the urease molecule is proposed, the first showing high affinity for the ligand, related with the loss of activity, and the second, of low affinity, related to polymerization process. 
  Reference    Z. Naturforsch. 35c, 1098—1100 (1980); received N ovember 12 1979 
  Published    1980 
  Keywords    Urease Inactivation, L-Usnic Acid, L-Cysteine, Binding Points 
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 TEI-XML for    default:Reihe_C/35/ZNC-1980-35c-1098_n.pdf 
 Identifier    ZNC-1980-35c-1098_n 
 Volume    35 
194Author    JohnA. ThompsonRequires cookie*
 Title    Narcissus pseudonarcissus  
 Abstract    A comparison of the EcoRI restriction endonuclease digest fragments from daffodil chrom oplast and chloro­ plast DNAs on agarose gels has yielded identical results. The sum of the fragments for each D NA gives a minim um molecular weight of 98.6 x 106. 
  Reference    Z. Naturforsch. 35c, 1101—11 (1980); received August 1 1980 
  Published    1980 
  Keywords    Chloroplast, Chromoplast, DNA, EcoRI Endonuclease, Narcissus 
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 TEI-XML for    default:Reihe_C/35/ZNC-1980-35c-1101_n.pdf 
 Identifier    ZNC-1980-35c-1101_n 
 Volume    35 
195Author    M. Frey, S. Rail, A. Roth, V. HemlebenRequires cookie*
 Title    Evidence for Uptake of Plamid DNA into Intact Plants (Lemna perpusilla) Proved by an E. coli Transformation Assay  
 Abstract    D NA Uptake, Lemna perpusilla, Plasmids The water plant Lemna perpusilla has been incubated with the E. coli plasmids pM B9 and pBR325, respectively. U ptake of plasmids has been shown by subsequent trans­ formation o f E. coli cells to tetracycline resistance after treatm ent with Lemna D NA from plasmid-incubated plants. In 7 out of 15 assays we found stable transformants. From the transform ation rate an am ount o f 10~* to 10-6 ng plasmid DNA per 10 |ig of plant D NA can be calculated. 
  Reference    Z. Naturforsch. 35c, 1104—1106 (1980); received N ovem ber 61980 
  Published    1980 
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 TEI-XML for    default:Reihe_C/35/ZNC-1980-35c-1104_n.pdf 
 Identifier    ZNC-1980-35c-1104_n 
 Volume    35 
196Author    Renate Meier, W. Erner Reisser, Wolfgang Wiessner, Marcelle Lefort-TranRequires cookie*
 Title      
 Abstract    Measurements of particle densities on the two freeze-fracture faces of digestive and perialgal vacuole mem­ branes in green and aposym biotic Paramecium bursaria Ehrbg. show distinct differences between the P-faces of both m em brane types. The distribution of particle den­ sities is more homogenous on the P-faces of perialgal vacuole membranes than on the P-faces o f digestive vacuole membranes. Possibly homogeneity among peri­ algal vacuole membranes reflects the stability o f perialgal vacuoles during their life cycle. Perhaps lysosomes cannot fuse with them. 
  Reference    Z. Naturforsch. 35c, 1107—1110 (1980); received October 28 1980 
  Published    1980 
  Keywords    Paramecium bursaria, Chlorella sp, Symbiosis, Membranes, Freeze-Fracture 
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 TEI-XML for    default:Reihe_C/35/ZNC-1980-35c-1107_n.pdf 
 Identifier    ZNC-1980-35c-1107_n 
 Volume    35 
197Author    Maja Mischel, Ingolf LamRequires cookie*
 Title    Dielectrophoretic Rotation in Budding Yeast Cells  
 Abstract    Rotation of budding yeast cells in an alternating non-uniform electric field of low frequency was investigated. Rotation frequency was found to be proportional to field strength above a threshold, and varied from cell to cell. The threshold is inversely correlated with the mom ent of inertia of the cells, while the slope of rotation frequency versus field strength increases with the moment. Rotation frequencies varied between 1 and 10 cycles per second. Clear differences between the dielectrophoretic behaviour o f living and heat-inactivated yeast cells were observed. 
  Reference    Z. Naturforsch. 35c, 1111 (1980); received July 21/Septem ber 10 1980 
  Published    1980 
  Keywords    Dielectrophoresis, Rotation, Yeast, N onuniform Electric Fields 
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 TEI-XML for    default:Reihe_C/35/ZNC-1980-35c-1111_n.pdf 
 Identifier    ZNC-1980-35c-1111_n 
 Volume    35 
198Author    G.Erhard PflughöftRequires cookie*
 Title    Zum Farbunterscheidungsvermögen der Honigbiene bei niedrigen Umgebungshelligkeiten Colour Discrim ination of the Honey Bee at Low Light Intensities  
 Abstract    Homing foragers of the honey bee (Apis mellifera carni-ca) were tested for discrim ination o f colour marks presen­ ted to them at the hive entrance. At a low rate o f natural il­ lum ination the bees were not able to distinguish the colou­ red (yellow, blue) marks from those with a corresponding gray. However, their general orientation was not disturbed. From this the conclusion is drawn that at low light intensi­ ties bees have an achrom atic vision besides their known co­ lour vision at higher intensities. 
  Reference    Z. Naturforsch. 35c, 1114—1116 (1980); received July 21/A ugust 26 1980 
  Published    1980 
  Keywords    Colour Vision, A chromatic Vision, Low Light Intensities, Honey Bee, Training Experiments 
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 TEI-XML for    default:Reihe_C/35/ZNC-1980-35c-1114_n.pdf 
 Identifier    ZNC-1980-35c-1114_n 
 Volume    35 
199Author    HeinzR. Em Bold, Jörg Eder, G. Abriele, M. UlrichRequires cookie*
 Title    Inhibition o f Allatotropic Activity and Ovary Development in Locusta migratoria by Anti-Brain-Antibodies  
  Reference    Z. Naturforsch. 35c, 1117—1119 (1980); received July 7/July 30 1980 
  Published    1980 
  Keywords    Locusta migratoria, Neurosecretion, Allatotropic Factor, A nti-Brain-A ntibodies, Ovary Development 
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 TEI-XML for    default:Reihe_C/35/ZNC-1980-35c-1117_n.pdf 
 Identifier    ZNC-1980-35c-1117_n 
 Volume    35 
200Author    Eberhard Horn, Brigitte RayerRequires cookie*
 Title    A Hormonal Component in Central Vestibular Compensation  
 Abstract    In developing clawed toads Xenopus laevis, the com pensa­ tion mechanism of behavioural defects caused by unilateral labyrinthectomy consists of two components, a vestibular one and a hormonal one. Thyroxine accelerates this com pensa­ tion. 
  Reference    Z. Naturforsch. 35c, 1120—1121 (1980); received August 18 1980 
  Published    1980 
  Keywords    Vestibular System, Central Compensation Thyroxine, Hy-pophysectomy, Xenopus 
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 TEI-XML for    default:Reihe_C/35/ZNC-1980-35c-1120_n.pdf 
 Identifier    ZNC-1980-35c-1120_n 
 Volume    35 
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