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  • Artikel  (49)
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  • Springer  (49)
  • 1980-1984  (49)
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  • 1980  (49)
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  • Artikel  (49)
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  • Springer  (49)
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  • 1980-1984  (49)
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  • 1
    Digitale Medien
    Digitale Medien
    Optimization of dye-laser output coupling by consideration of the spatial gain distribution (1980)
    Springer
    Applied physics 22 (1980), S. 175-184 
    Details
    ISSN: 1432-0630
    Schlagwort(e): 42.55
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Maschinenbau , Physik
    Notizen: Abstract The problem of output-coupling optimization of a transversely or longitudinally pumped dye laser is treated in terms of a rate equation approach under steady state considerations. The theoretical study considers the spatial variation of the gain distribution and such typical features of a dye laser as reabsorption, triplet effects and excited state absorption. Numerical results obtained with realistic values of typical laser parameters (cross-sections for stimulated emission and reabsorption, number density of active molecules etc.) indicate that a higher degree of output coupling and consequently higher output powers are feasible upon a complete consideration of the spatial gain distribution
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00886002
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  • 2
    Digitale Medien
    Digitale Medien
    New TEA-lasers based onD′→A′ transitions in halogen monofluoride compounds: ClF (284.4 nm), BrF (354.5 nm), IF (490.8 nm) (1980)
    Springer
    Applied physics 23 (1980), S. 283-287 
    Details
    ISSN: 1432-0630
    Schlagwort(e): 42.55 ; 42.80 ; 33
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Maschinenbau , Physik
    Notizen: Abstract As an outcome of a systematic study of excitation kinetics and fluorescence spectra concerning theD′(3π2u )→A′(3π2g ) transitions in homonuclear diatomic halogens and corresponding transitions in interhalogen molecules [1], this paper describes, for the first time, TEA laser action in the three halogen monofluorides ClF, BrF, and IF. Output energies in the mJ range were demonstrated in a fast TEA discharge arrangement at the wavelengths of 284.4, 354.5, and 490.8 nm for ClF, BrF, and IF, respectively. The results suggest parameter scalability and wavelength tunability.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00914912
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  • 3
    Digitale Medien
    Digitale Medien
    The effect of substituting metal vapour with metal halide vapour in a hollow cathode laser discharge (1980)
    Springer
    Applied physics 21 (1980), S. 25-28 
    Details
    ISSN: 1432-0630
    Schlagwort(e): 35 ; 42.55
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Maschinenbau , Physik
    Notizen: Abstract He−Zn and He−ZnCl2 hollow cathode discharges were compared. The metal vapour concentration necessary for laser operation can be achieved at a lower temperature for the molecular substance. On the other hand, the efficiency decreases because part of the He ions necessary for the selective excitation of the upper laser level of the metal ion are lost in the dissociation process.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00886479
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  • 4
    Digitale Medien
    Digitale Medien
    Application of pressure-tuned diode lasers to high-resolution spectroscopy (1980)
    Springer
    Applied physics 22 (1980), S. 241-243 
    Details
    ISSN: 1432-0630
    Schlagwort(e): 07.65 ; 42.55 ; 42.80
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Maschinenbau , Physik
    Notizen: Abstract The application of the high-pressure chamber with a pressure transmitting medium (liquid at room temperature) to diode-laser tuning was found to be a useful method for high-resolution spectroscopy. Ammonia absorbtion spectra in the 10 μm region were recorded with a resolution approaching the Doppler limit.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00886014
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  • 5
    Digitale Medien
    Digitale Medien
    Wide-range line-tunable oscillation of an optically pumped NH3 laser (1980)
    Springer
    Applied physics 21 (1980), S. 237-240 
    Details
    ISSN: 1432-0630
    Schlagwort(e): 42.55 ; 42.60 ; 34.50
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Maschinenbau , Physik
    Notizen: Abstract Selective single-line oscillation has been obtained from an NH3 laser in the range from 11 to 13 μm. Pumping of high pressure NH3−He mixture with theR(30) line of a TEA-CO2 laser made it possible to tune on more than 30 lines with the aid of a grating. However, such line tunable oscillation was not observed when theR(16) line was used for pumping. Reasons for this difference are discussed.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00886173
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  • 6
    Digitale Medien
    Digitale Medien
    Simplification of the helical TE N2 laser (1980)
    Springer
    Applied physics 21 (1980), S. 319-321 
    Details
    ISSN: 1432-0630
    Schlagwort(e): 42.55 ; 42.60
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Maschinenbau , Physik
    Notizen: Abstract We report the observation that the helical TE N2 laser can effectively be simplified by giving up the use of decoupling elements as well as by abolishing the segmentation of the electrode structure. Although, as a consequence of this simplification, the operating pressure range was slightly decreased, the output power could be improved by roughly 30%, a result which is attributed to the new electrode geometry exhibiting lower inductance and lower damping losses.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00895921
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  • 7
    Digitale Medien
    Digitale Medien
    Selective action on nucleic acids components by picosecond light pulses (1980)
    Springer
    Applied physics 21 (1980), S. 391-395 
    Details
    ISSN: 1432-0630
    Schlagwort(e): 87 ; 42.55 ; 82.50
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Maschinenbau , Physik
    Notizen: Abstract We report on first attempts for selective action on nucleic acid components, namely uracil and adenine, using picosecond light pulses. Selective action was achieved both in the case of irradiation of mixtures of bases and in the case of irradiation of mixtures of different nucleic acids components, which contain uracil and adenine.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00895931
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  • 8
    Digitale Medien
    Digitale Medien
    Periodic pulse solutions of a laser consisting of a pair of amplifiers mode locked by a fast saturable absorber (1980)
    Springer
    Applied physics 22 (1980), S. 213-218 
    Details
    ISSN: 1432-0630
    Schlagwort(e): 42.55 ; 42.60 ; 42.65
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Maschinenbau , Physik
    Notizen: Abstract We present periodic solutions, which are described in terms of Jacobian elliptic functions, for the steady state pulses from a laser system consisting of a pair of amplifiers of unequal relaxation time mode locked by a “fast” saturable absorber. The pulsewidth and the average power in the pulse are expressed interms of the system parameters through two different approaches, where detailed plots are given for one of the approaches. Summary of the characters to be possessed by the amplifier pair to ensure the reliable production of shortest possible pulses is given.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00886009
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  • 9
    Digitale Medien
    Digitale Medien
    Modelling of a solar-pumped MHD excimer laser (1980)
    Springer
    Applied physics 22 (1980), S. 277-281 
    Details
    ISSN: 1432-0630
    Schlagwort(e): 42.55 ; 52
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Maschinenbau , Physik
    Notizen: Abstract An analytical model is applied to the concept of a solar-pumped MHD laser utilizing the CsXe excimer and Cs2 dimerA-X laser transitions. The model predicts practical gain coefficients on the excimer band for supersonic flow of a 2000 K, 20 atmosphere cesium-xenon plasma across a ∼10 kG magnetic field.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00899877
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  • 10
    Digitale Medien
    Digitale Medien
    Gasdynamic CO laser with closed-cycle gas flow (1980)
    Springer
    Applied physics 22 (1980), S. 421-427 
    Details
    ISSN: 1432-0630
    Schlagwort(e): 42.55 ; 47 ; 52
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Maschinenbau , Physik
    Notizen: Abstract The operation of an electrically excited gasdynamic CO laser with closed-cycle gas flow is described. Details of the gasdynamics, the recompression, and the cooling of the flowing gas are given. The electrical discharge produces contaminating gas compounds—in particular CO2—which accumulate in the recirculating gas. The resulting transient behavior of the laser gas composition, the discharge characteristics, and the laser performance are studied and compared with the results obtained with the same CO laser in an open-flow system. It is found that the closed-cycle system may be operated for considerable time if the CO2 contamination is removed from the laser gas.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00901068
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  • 11
    Digitale Medien
    Digitale Medien
    Solubility limit of impurities in silicon after laser induced melting (1980)
    Springer
    Applied physics 23 (1980), S. 15-19 
    Details
    ISSN: 1432-0630
    Schlagwort(e): 64.75+g ; 61.70T ; 42.55
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Maschinenbau , Physik
    Notizen: Abstract The solubility of several dopants (Sb, Ga, Bi, In) in laser treated silicon has been investigated. The dopants were introduced by vacuum deposition followed by ruby laser irradiation. Their solubility was determined by Rutherford backscattering spectroscopy measurements in channelling and random conditions. In all cases, a maximum solubilityC S * , much higher than the equilibrium solubility limitC S 0 and independent of the pulsed laser energy density, was found. The values obtained are in good agreement with those calculated from a simple model based on phase diagram considerations, using the relationship: $$C_S^* = \frac{{C_S^0 }}{{k_0 }}k^* ,$$ wherek 0 andk * are the equilibrium and effective distribution coefficients. Finally, the existence of a new solubility limit for a laser treatment is discussed.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00899564
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  • 12
    Digitale Medien
    Digitale Medien
    New cw FIR laser lines from optically pumped ammonia analogues (1980)
    Springer
    Applied physics 23 (1980), S. 127-130 
    Details
    ISSN: 1432-0630
    Schlagwort(e): 42.55
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Maschinenbau , Physik
    Notizen: Abstract Two new cw submillimetre lines optically pumped by the 9 μR(30) CO2 laser have been observed for14NH3 and assigned to thea(6,0)→s(5,0) transition and to its cascade transitions(5,0)→a(4,0) in thev 2=1 state. In addition, six new emission lines have been observed for NH2D, and one tentatively assigned to the (11,1)→(10,1) transition of ND3. Methylamine has also been investigated and twenty-eight new emission lines have been discovered.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00899706
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  • 13
    Digitale Medien
    Digitale Medien
    A high power N2-laser of long pulse duration (1980)
    Springer
    Applied physics 23 (1980), S. 341-344 
    Details
    ISSN: 1432-0630
    Schlagwort(e): 42.55
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Maschinenbau , Physik
    Notizen: Abstract An N2-laser of 19 ns pulse-duration and an energy of 30 mJ has been developed and examined. A dc preionization, a grooved electrode and a partial electrical screening of the discharge tube permit reproducible single-shot operation and yield a homogeneous beam.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00903212
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  • 14
    Digitale Medien
    Digitale Medien
    Detection of CO2-laser power variations via plasma tube impedance changes (1980)
    Springer
    Applied physics 21 (1980), S. 407-409 
    Details
    ISSN: 1432-0630
    Schlagwort(e): 42.55 ; 52 ; 85.60
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Maschinenbau , Physik
    Notizen: Abstract A method is described for detection of CO2-laser power variations which requires no optical detector. It is based on plasma-tube impedance changes induced by the laser power flow within the cavity. A constant-current high-voltage power supply and a special equalizer are necessary to obtain a voltage proportional to the laser power. Details for the design of the equalizer are given. The detection scheme works for frequencies up to about 5 kHz and can be used for laser frequency stabilization or signature analysis.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00895933
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  • 15
    Digitale Medien
    Digitale Medien
    Stability of Pin electrode CO2-lasers (1980)
    Springer
    Applied physics 22 (1980), S. 149-154 
    Details
    ISSN: 1432-0630
    Schlagwort(e): 42.55 ; 52
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Maschinenbau , Physik
    Notizen: Abstract The stability of parallel pin electrode CO2-laser discharges, coupled by carrier diffusion only, against concentration of current in one column and subsequent transition into an arc, is investigated theoretically. A small signal description of the time dependent behaviour of a column with falling characteristic caused by a wall sheath of considerable width is used. It is shown that an inductance in series to each discharge is not able to avoid glow to arc transition, though enlarges the duration of the glow.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00885998
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  • 16
    Digitale Medien
    Digitale Medien
    Spectral, fluorescent, photochemical and laser properties of some organic compound vapors (1980)
    Springer
    Applied physics 23 (1980), S. 83-87 
    Details
    ISSN: 1432-0630
    Schlagwort(e): 33 ; 82.50 ; 42.55
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Maschinenbau , Physik
    Notizen: Abstract Absorption and fluorescence spectra of rarefied vapors ofp-terphenyl, 1,4-bis-[2(5-phenyloxazolyl)]-benzene, 2,5-diphenyl-1,3,4-oxadiazole, 2,5-diphenyl-1,3-oxazole, 2,5-diphenylfuran are measured. Extinction coefficients, quantum yields of fluorescence and one-photon decomposition of molecules are determined for vapors excited by pulsed laser radiation at 266 and 355 nm in the temperature range from 200 to 400°C. It is shown that for all cases studied the one-photon decomposition is only a small part of the total quantum yield of the radiationless deactivation of the fluorescent state. Laser action has, for the first time, been obtained in 2,5-diphenylfuran vapor at 356 nm.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00899574
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  • 17
    Digitale Medien
    Digitale Medien
    Effect of laser dye deterioration on performance (1980)
    Springer
    Applied physics 22 (1980), S. 171-174 
    Details
    ISSN: 1432-0630
    Schlagwort(e): 42.55 ; 82.50
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Maschinenbau , Physik
    Notizen: Abstract A previous analysis that described loss of gain in a dye solution as a result of photochemical decomposition by pump photons is refined and is extended to the situation where impurities absorb at the pump wavelength. A limitation in the first paper is that it described only a single absorption depth in the medium at a constant pump fluxI p. The present examination includes the fall-off ofI p and integrates the total signal output with depth for a single-pass amplifier operated in the fully saturated gain condition. The equations are simpler, but as before loss of output, expressed in terms of a quantum yield of laser decayQ L, is minimized for a photochemically bleachable dye, and for one with high gain. Pumping in the vicinity of the absorption maximum is also advantageous.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00886001
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  • 18
    Digitale Medien
    Digitale Medien
    Infrared fluorescence and laser action of fast mode-locking dyes (1980)
    Springer
    Applied physics 22 (1980), S. 355-359 
    Details
    ISSN: 1432-0630
    Schlagwort(e): 32 ; 42.55
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Maschinenbau , Physik
    Notizen: Abstract Fluorescence spectra in the near infrared are observed of the dye Eastman 9860 and of new, faster mode-locking dyes. The quantum efficiencies are determined to be small with η≃10−3. The short fluorescence lifetimes are deduced from optical gain measurements. The fluorescence time-constants are found to have the same value as the corresponding absorption recovery times. Even laser action is observed in these fast saturable absorbers previously belieyed to be non-fluorescent.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00901056
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  • 19
    Digitale Medien
    Digitale Medien
    A novel picosecond-pulse dye laser system (1980)
    Springer
    Applied physics 23 (1980), S. 135-140 
    Details
    ISSN: 1432-0630
    Schlagwort(e): 42.55
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Maschinenbau , Physik
    Notizen: Abstract A laser system capable of generating picosecond pulses of 2 ps duration and peak powers of up to 50 MW, tunable throughout the emission spectrum of the lasing medium is described. The system consists of a cw dye laser which is tuned and is actively mode-locked by means of a novel interferometer. Single-pulse amplification is achieved via a two-stage N2-laser-pumped amplifier arrangement. One of the most attractive features of the system here described is its inherent versatile broad tunability, which should allow, with different lasing media and pump sources, ps pulse generation from 400 to 700 nm using the same interferometer device.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00899708
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  • 20
    Digitale Medien
    Digitale Medien
    An analysis of stimulated longitudinal electrostatic bremsstrahlung in a free-electron laser structure (1980)
    Springer
    Applied physics 23 (1980), S. 295-298 
    Details
    ISSN: 1432-0630
    Schlagwort(e): 41 ; 42.55
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Maschinenbau , Physik
    Notizen: Abstract An analysis of stimulated emission of radiation by an electron beam passing through a periodic longitudinal electrostatic field is presented, and its use in a free-electron laser structure is discussed. The analysis is based on a coupled-mode calculation of the interaction between a waveguided electromagnetic mode and an electron-beam plasma with finite cross section. The dispersion equation derived applies to the collective as well as the single electron regime.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00914914
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  • 21
    Digitale Medien
    Digitale Medien
    Excimers and excimer lasers (1980)
    Springer
    Applied physics 21 (1980), S. 95-114 
    Details
    ISSN: 1432-0630
    Schlagwort(e): 42.55 ; 42.60
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Maschinenbau , Physik
    Notizen: Abstract The development of excimers and excimer lasers are reviewed. The excimers of the noble gases (Xe 2 * , Kr 2 * , Ar 2 * ) and of the noble gas halides (e.g. KrF, XeCl) which, respectively, radiate in the vacuum ultra-violet and ultra-violet regions of the spectrum are described in terms of their structure, spectroscopy and formation kinetics and the methods of pumping, operational characteristics and applications of the lasers are discussed.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00900671
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  • 22
    Digitale Medien
    Digitale Medien
    Experimental method for the measurement of hyperfine transition saturation intensities in a gaseous medium (1980)
    Springer
    Applied physics 21 (1980), S. 135-140 
    Details
    ISSN: 1432-0630
    Schlagwort(e): 35 ; 42.55 ; 42.80
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Maschinenbau , Physik
    Notizen: Abstract A saturated absorption technique, using an actively stabilized cw dye laser has been developed to measure the saturation intensities of hyperfine transitions in a gaseous medium. Hyperfine lines belonging to theB-X system of molecular iodine have been investigated. The experimental method proposed, provides a means for measurement of the absolute value of the saturation parameter of the transition with an accuracy better than 10%. The behavior of the saturation intensity of some transitions with iodine pressure has been investigated in the range 30 m Torr→90mTorr.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00900675
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  • 23
    Digitale Medien
    Digitale Medien
    Energy transfer in constant period free-electron lasers (1980)
    Springer
    Applied physics 22 (1980), S. 219-225 
    Details
    ISSN: 1432-0630
    Schlagwort(e): 42.55
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Maschinenbau , Physik
    Notizen: Abstract A simple single particle model of a free-electron laser (FEL) amplifier has been used in a computer simulation to determine the maximum fractional conversion of electron kinetic energy to laser energy. The simulation results can be represented by a single universal curve. A simple scaling relationship for the length of the optimized constant period helix together with the universal curve permit one to predict maximum fractional energy conversion for any set of values of initial electron energy, initial laser intensity, magnetic field amplitude, and magnet period.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00886010
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  • 24
    Digitale Medien
    Digitale Medien
    Investigation of the spatial coherence of a laser beam by a laser-induced grating method (1980)
    Springer
    Applied physics 23 (1980), S. 299-302 
    Details
    ISSN: 1432-0630
    Schlagwort(e): 42.30 ; 42.55 ; 42.65
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Maschinenbau , Physik
    Notizen: Abstract The spatial coherence function |Γ(s)| of ruby laser pulses has been measured by self-diffraction at a laser-induced grating depending on the distances between two points in the beam profile. The spatial coherence of the laser beam was changed by operating the laser in the fundamental transverse mode, in a transverse multimode and by applying different pump powers. The degree of spatial coherence was experimentally found to be a Gaussian, as described by the Collett-Wolf model. The new method for measuring the spatial coherence function |Γ(s)| is described and possible improvements are discussed.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00914915
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  • 25
    Digitale Medien
    Digitale Medien
    New cw optically pumped FIR emissions in HCOOH, D2CO and CD3Br (1980)
    Springer
    Applied physics 23 (1980), S. 345-348 
    Details
    ISSN: 1432-0630
    Schlagwort(e): 42.55
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Maschinenbau , Physik
    Notizen: Abstract New FIR emissions lines have been observed for HCOOH, D2CO and CD3Br. Assignments have been made of the HCOOH lines and for most of those of CD3Br. For D2CO, most of the new emissions showed a corresponding cascade transition.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00903213
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  • 26
    Digitale Medien
    Digitale Medien
    Immunocytochemical localization of reserve protein in the endoplasmic reticulum of developing bean (Phaseolus vulgaris) cotyledons (1980)
    Springer
    Planta 150 (1980), S. 419-425 
    Details
    ISSN: 1432-2048
    Schlagwort(e): Cotyledons ; Endoplasmic reticulum ; Ferritin labeling ; Immunocytochemistry ; Phaseolus ; Protein (reserve) ; Reserve protein
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract The ultrastructure of the storage parenchyma cells of the cotyledons of developing bean (Phaseolus vulgaris L.) seeds was examined in ultrathin frozen sections of specimens fixed in a mixture of glutaraldehyde, formaldehyde and acrolein, infused with 1 M sucrose, and sectioned at-80° C. Ultrastructural preservation was excellent and the various subcellular organelles could readily be identified in sections which had been stained with uranyl acetate and embedded in Carbowax and methylcellulose. The cells contained large protein bodies, numerous long endoplasmic reticulum cisternae, mitochondria, dictyosomes, and electron-dense vesicles ranging in size from 0.2 to 1.0 μm. Indirect immunolabelling using rabbit immunoglobulin G against purified phaseolin (7S reserve protein), and ferritin-conjugated goat immunoglobulin G against rabbit immunoglobulin G was used to localize phaseolin. With a concentration of 0.1 mg/ml of anti-phaseolin immunoglobin G, heavy labeling with ferritin particles was observed ober the protein bodies, the cisternae of the endoplasmic reticulum, and the vesicles. The same structures were lightly labeled when the concentration of the primary antigen was 0.02 mg/ml. Ferritin particles were also found over the Golgi bodies. The absence of ferritin particles from other organelles such as mitochondria and from areas of cytoplasm devoid of organelles indicated the specificity of the staining, especially at the lower concentration of anti-phaseolin immunoglobulin G.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00390179
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  • 27
    Digitale Medien
    Digitale Medien
    Immunocytochemical localization of somatostatin-containing neurons in the brain of Rana temporaria (1980)
    Springer
    Cell & tissue research 205 (1980), S. 43-53 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Brain ; Rana temporaria ; Somatostatin-containing neurons ; Immunocytochemistry
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The brain of the frog Rana temporaria was studied at the light microscopic level with the use of a double immunocytochemical staining method. The telencephalon, diencephalon and rhombencephalon contain somatostatin perikarya and fibers. In the telencephalon, the location of the somatostatin neurons largely corresponds to that of mammals. In the hypothalamus, the somatostatin perikarya are located in and near the magnocellular preoptic nucleus and also in the pars ventralis of the tuber cinereum. Like the somatostatin neurons of the rat hypothalamus, they form a separate subpopulation, different from the neurons producing neurohypophysial hormones. In Rana, somatostatin neurons are also present in (as well as in the vicinity of) the subfornical organ, in the thalamus, the tectum opticum, the interpeduncular nucleus and the caudal end of the roof of the calamus scriptorius. A precise localization of the perikarya of most somatostatin fibers, including those found in the median eminence and the neural lobe, was not attained.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00234441
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  • 28
    Digitale Medien
    Digitale Medien
    Immunofluorescence study of LRH-producing neurons in prosimians (Tupaia and Galago) (1980)
    Springer
    Cell & tissue research 206 (1980), S. 355-365 
    Details
    ISSN: 1432-0878
    Schlagwort(e): LRH neurons ; Prosimians (Tupaia, Galago) ; Fluorescence ; microscopy ; Immunocytochemistry
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Reactive LRH neurons were characterized in prosimians (Tupaia and Galago) by immunofluorescence using rabbit immunesera against unconjugated synthetic LRH, or LRH conjugated with bovine serum albumin. These neurons, which vary individually in number in one species, are mainly concentrated in the rostral hypothalamus (medial preoptic area and anterior hypothalamic area) and in the lamina terminalis. In contrast to the simians and man, immunoreactive perikarya were not routinely found in the mediobasal hypothalamus of the prosimians investigated in the present study. Reactive axons of the hypothalamo-hypophyseal tract are more numerous and conspicuous in the retrochiasmatic area and in the postinfundibular eminence. They give rise to radiating collaterals ending mainly around the capillaries of the primary portal plexus of the median eminence and of the infundibular stem (where they are generally more numerous). Reactive axons of the preopticoterminal tract, originating from the perikarya of the lamina terminalis, end around the capillaries of the vascular organ or below and between the ependymal cells lining its ventricular side. In Galago a small but very distinct tract of reactive axons runs under the optic chiasma, between the lamina terminalis and the ventral labium of the infundibulum. Very fine reactive extrahypothalamic axons were observed in the posterior part of the habenular ganglia, along the preamygdaloid portion of the stria terminalis and along the blood vessels of the parolfactory area.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00237965
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  • 29
    Digitale Medien
    Digitale Medien
    Gut hormones in Salamandra salamandra (1980)
    Springer
    Cell & tissue research 211 (1980), S. 331-343 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Gut hormones ; Endocrine cells ; Electron microscopy ; Immunocytochemistry ; Peptidergic innervation
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Histological, cytochemical and immunocytochemical methods were used in light and electron microscopical studies to demonstrate the presence of a neuroendocrine system in the gut of the urodele, Salamandra salamandra. Cytochemical stains capable of detecting peptide-producing endocrine cells demonstrate cells reacting with Masson's silver (argentaffin) method, Grimelius' argyrophil silver method, masked metachromasia method and the lead haematoxylin stain. Using antisera raised to a variety of mammalian gut peptides, cells containing bombesin-, gastrin-, somatostatin-, substance P- and glucagon-like immunoreactivity were identified; vasoactive intestinal polypeptide- and substance P-like immunoreactivities were found in nerve fibres in the submucous and myenteric plexus. No immunoreactivity was detected for motilin, gastric inhibitory polypeptide, cholecystokinin or secretin. The ultrastructure of the immunoreactive cells and nerves was revealed by the semithin/thin method. All the cells identified contained numerous electrondense secretory granules, which varied in their chracteristic morphological structure from one cell type to another. The evidence collected in this study indicates that a complex neuroendocrine system regulating gut function is present in this amphibian and may have developed prior to the emergence of the phylum.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00236453
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  • 30
    Digitale Medien
    Digitale Medien
    Differentiation of embryonic hypothalamic transplants cultured on the choroidal pia in brains of adult rats (1980)
    Springer
    Cell & tissue research 205 (1980), S. 217-228 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Hypothalamus (rat) ; Differentiation ; Transplant ; Histofluorescence ; Immunocytochemistry ; Autoradiography
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Hypothalamic tissue from 16 to 18-day fetal rats was transplanted onto the choroidal pia overlying the superior colliculus in adult female rats. After survival periods of 2 weeks to 19 months, brains containing transplants were processed for monoamine fluorescence histochemistry, immunohistochemistry for three neuropeptides (LHRH, somatostatin, neurophysin), or for autoradiography in ovariectomized hosts that received [3H] estradiol. Most of the transplants survived and retained or increased in size; 14 of 25 transplants examined by fluorescence histochemistry were found to contain median eminence-like structures. In almost all of the transplants that were stained for neuropeptides, beaded processes and occasional cell bodies were observed. Although immunoreactive fibers were found near blood vessels, no palisade arrangement typical of the normal median eminence was evident. Each of the hypothalamic transplants on which steroid autoradiography was performed contained clusters of estrophilic neurons, the intensity of labeling of which was comparable to that seen in the host hypothalamus. These results indicate that many characteristic morphological and chemical features of the hypothalamus, which are not evident in the 16 to 18-day fetus, are elaborated in transplants during the survival period in the host. Transplantation of fetal hypothalamus to adult choroidal pia thus appears to be a valuable approach for studying the factors, humoral or neural, that regulate the differentiation of this brain region.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00234681
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  • 31
    Digitale Medien
    Digitale Medien
    Evidence that lipolytic peptide B occurs in the ACTH/MSH-cells of the pituitary and in the brain (1980)
    Springer
    Cell & tissue research 205 (1980), S. 349-359 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Lipolytic peptide B ; Pituitary ; ACTH/MSH cells ; Brain ; Immunocytochemistry
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Several lipid-mobilizing peptides occur in the pituitary, among them β-lipotropin and “lipolytic peptide A and peptide B”. The latter two peptides are distinct from β-lipotropin and appear to be chemically related to the neurophysins. Immunohistochemistry has now revealed that the lipolytic peptide B of the pituitary is localized in the ACTH- and MSH-cells. In addition, immunoreactive peptide B was found in axons of the posterior lobe of the pituitary. Immunoreactive peptide B was found also in nerve fibers and nerve cell bodies in the hypothalamus, particularly in the hypothalamo-hypophyseal tract and in the magnocellular neuronal system. Immunoreactive nerve fibers were numerous also in the periventricular nucleus of the thalamus. The antiserum against peptide B cross-reacts with neurophysin I, and hence, it cannot be excluded that at least part of the immunostaining in the brain reflects the presence of the latter component. However, the regional distribution of immunoreactive peptide B and neurophysin was not identical. Therefore, it is possible that authentic peptide B occurs not only in the pituitary but also in the brain.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00232277
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  • 32
    Digitale Medien
    Digitale Medien
    Localisation of pancreatic polypeptide (PP)-like immunoreactive material in neurones of the brain of the blowfly, Calliphora erythrocephala (Diptera) (1980)
    Springer
    Cell & tissue research 210 (1980), S. 101-109 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Pancreatic polypeptide (PP)-like material ; Immunocytochemistry ; Neuropeptides ; Neurosecretory cells ; Calliphora erythrocephala
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The brain of the blowfly, Calliphora erythrocephala, has been studied by means of the peroxidase-antiperoxidase immunocytochemical method, with the use of antibodies to bovine pancreatic polypeptide (BPP). A number of immunoreactive neurones have been localised, some corresponding to neurones previously identified tentatively as neurosecretory. This finding is further evidence that biologically active peptides, previously considered to be “vertebrate”, also exist in invertebrates. It also supports the concept of their evolutionary origin in nervous tissue.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00232146
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  • 33
    Digitale Medien
    Digitale Medien
    The topography of mesotocin and vasotocin systems in the brain of the domestic mallard and japanese quail: Immunocytochemical identification (1980)
    Springer
    Cell & tissue research 213 (1980), S. 37-51 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Mesotocin neurons ; Vasotocin neurons ; Avian hypothalamus ; Preoptic area ; Immunocytochemistry
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The neurosecretory systems producing mesotocin (MT) and vasotocin (VT) (the avian homologues of oxytocin and vasopressin, respectively) were characterized in the brains of the domestic mallard and Japanese quail by means of indirect immunofluorescence techniques using specific antisera. In the anterior preoptic region, including the organum vasculosum of the lamina terminalis, and at different levels of the supraoptic and paraventricular nuclei, separate mesotocin- and vasotocin-producing neurons were identified. Mesotocinergic and vasotocinergic neurons were also located in the tuberomammillary area, among the ectomammillary tract fibers. The supraoptico-neurohypophysial tract, formed by vasotocin- and mesotocincontaining axons, enters the internal zone of the median eminence and ends in the posterior lobe of the pituitary. The external zone of the rostral median eminence appears to contain vasotocin and mesotocin fibers, which terminate in close contact with the capillaries of the hypophysial portal system.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00236919
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  • 34
    Digitale Medien
    Digitale Medien
    Transcription and processing of rRNA in higher plant cells (Daucus carota, Petroselinum crispum, Acer pseudoplatanus) (1980)
    Springer
    Plant systematics and evolution 134 (1980), S. 11-21 
    Details
    ISSN: 1615-6110
    Schlagwort(e): Angiosperms ; Daucus ; Petroselinum ; Acer ; rRNA ; transcription ; precursors of less than 2.5 × 106 daltons ; processing
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Actively dividing cells from parsley (Petroselinum crispum) and carrot (Daucus carota) (bothApiaceae) andAcer pseudoplatanus (Aceraceae) were used to detect the primary gene product of the rDNA in plant cells. Parsley and carrot cells were labelled with [32P] orthophosphate. In both cases only one high molecular weight rRNA precursor was present on polyacrylamide gels under non-denaturing conditions. Its molecular weight did not exceed 2.5 × 106 daltons. The component emerged from the heterogenous material after a labelling period of 5–10 min. In parsley cells 45 min after onset of incubation labelled mature rRNA (25S and 18S) arrived in the cytoplasm. InAcer pseudoplatanus (incubation period 60 min) two rapidly labelled components did emerge from polyacrylamide gels; their molecular weights were 2.3 and 3.2− 3.4 × 106 daltons. After electrophoresis under denaturing conditions the larger component was no longer present, thus indicating that it was an aggregate of different RNA molecules. The molecular weights of the rRNA precursors ofD. carota andP. crispum determined after electrophoresis in formamide gels were about 2.1 × 106 daltons. From these results we have no evidence for the existence of rRNA precursors exceeding the molecular weight of 2.5 × 106 daltons.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00985028
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  • 35
    Digitale Medien
    Digitale Medien
    Reproductive biology in the primitive relic AngiospermDrimys brasiliensis (Winteraceae) (1980)
    Springer
    Plant systematics and evolution 135 (1980), S. 11-39 
    Details
    ISSN: 1615-6110
    Schlagwort(e): Angiosperms ; Winteraceae ; Drimys brasiliensis ; Development of inflorescences ; flowers and fruits ; reproductive biology ; pollination ; seed dispersal ; vegetative propagation ; early Angiosperm evolution
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract From field observations onDrimys brasiliensis, principally in the Botucatu region of São Paulo State, Brazil, new data on the reproductive biology, the rhythm of growth, and the development of lateral cymose inflorescences, flowers and fruits are presented. Pollination accelerates the rate of flower-development for about 4–6 days. Pollination experiments show thatD. brasiliensis is not self-sterile; because of mechanical devices the sticky pollen grains do not normally come into contact with the stigmata unless an animal pollen vector is involved. The pollinators are diurnalColeoptera, Diptera andThysanoptera which eat from the pollen, lick from the stigmatic exudates and (in case of the flies) probably also from the staminal glands. Fruit- and seedeaters are birds which seem to be the main dispersal agents. Establishment of new individuals normally is through seedlings, but also by vegetative propagation through plagiotropous branches which may root and separate from the mother plant. The morphological, developmental and reproductive aspects inD. brasiliensis are discussed in a wider context, compared with data from otherMagnoliidae, and related to aspects of early Angiosperm evolution.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00983005
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  • 36
    Digitale Medien
    Digitale Medien
    Species relationships and genetic variation in the diploid wheats (Triticum, Aegilops) as revealed by starch gel electrophoresis (1980)
    Springer
    Plant systematics and evolution 136 (1980), S. 247-258 
    Details
    ISSN: 1615-6110
    Schlagwort(e): Angiosperms ; Poaceae (=Gramineae) ; Triticum ; Aegilops ; diploid species ; Starch Gel electrophoresis ; allozymic variation ; phylogenetic relationships ; evolution
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Twenty enzyme loci were examined in the diploid species ofTriticum andAegilops for allelic variation by starch gel electrophoresis. SectionSitopsis, including the five species,Ae. speltoides, Ae. lingissima, Ae. sharonensis, Ae. bicornis andAe. searsii form a close subgroup withAe. speltoides slightly removed from the others.T. monococcum s. lat., was found to be closest to the species of theSitopsis group.Ae. comosa, Ae. umbellulata andAe. uniaristata form a second subgroup withAe. caudata most closely related to these species.Ae. squarrosa appears almost equally related to all of the species, showing no special affinity for any one species group. Nineteen out of twenty loci examined were polymorphic with a mean of 6.7 alleles per locus. Species could be, for most loci, characterized by the presence of predominant alleles. A conspicious genetic characteristic ofTriticum-Aegilops is the sharing of these predominant alleles between species. Within species variation is characterized by a diffuse distribution of secondary alleles.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF01004629
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  • 37
    Digitale Medien
    Digitale Medien
    Gene flow inAgrostis tenuis (Poaceae) (1980)
    Springer
    Plant systematics and evolution 134 (1980), S. 23-31 
    Details
    ISSN: 1615-6110
    Schlagwort(e): Angiosperms ; Poaceae ; Agrostis tenuis ; Copper tolerance ; Selection ; gene flow
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract The copper tolerance of both adult plants and their seedlings, ofAgrostis tenuis from sites within and outside, but neighbouring the Parys Mountain mine (North Wales) were studied. Intensive sampling was carried out along a line starting from the mine boundaries to a distance of five miles away in the direction of the prevailing wind, and of two miles in an upwind direction. The test have shown that mine populations are very tolerant. In outside populations on soils with reduced of very low copper content the mean tolerance level of the seedlings is considerably higher than that of corresponding adult plants, while both show a gradual decrease in tolerance with distance from the mine. The gene flow moves in the direction of the prevailing wind transfering tolerant characters from the mine to the normal populations. The selective pressures on the toxic soil of the mine are quite strong and permit ± tolerant plants only, while on normal soils these pressures are not so severe, so that populations may be rather heterogenous regarding their tolerance towards copper.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00985029
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  • 38
    Digitale Medien
    Digitale Medien
    Species novae generisEremostachys (Labiatae) (1980)
    Springer
    Plant systematics and evolution 134 (1980), S. 127-131 
    Details
    ISSN: 1615-6110
    Schlagwort(e): Angiosperms ; Labiatae =Lamiaceae ; Eremostachys codonocalyx ; E. stenocalycina ; E. salangensis ; E. freitagii ; E. andersii ; new species ; Flora of Afghanistan and Iran
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Five new species are described:Eremostachys codonocalyx from NE. Iran (related toE. subspicata),E. stenocalycina from NE. Afghanistan (related toE. alberti andE. hissarica),E. salangensis from NE. Afghanistan (close toE. bamianica),E. freitagii from E. Afghanistan (similar but not closely related toE. vulnerans), andE. andersii from E. Afghanistan (similar but not closely related toE. vulnerans), andE. andersii from NE. Afghanistan of isolated systematic position.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00985034
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  • 39
    Digitale Medien
    Digitale Medien
    Zinc and copper effects on metal-tolerant and non-tolerant clones ofAgrostis tenuis (Poaceae) (1980)
    Springer
    Plant systematics and evolution 134 (1980), S. 173-182 
    Details
    ISSN: 1615-6110
    Schlagwort(e): Angiosperms ; Poaceae ; Agrostis tenuis ; Tolerance to toxic heavy metals ; Cu ; Zn ; and combinations
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract The toxicity of various Cu and Zn concentrations, as well as their mutual influence upon tolerant and non-tolerant clones ofAgrostis tenuis originating from soils of different metal content has been studied. Specific resistance has been clearly established. Co-existence of toxic metals causes an increase in toxicity. Uptake of metals (Cu and Zn) obviously occurs rather independently, and the toxic activity of the one is not affected competitively by the presence of the other. Above normal concentrations of Cu and Zn negatively affect cell division and growth in roots of non-tolerant genotypes. There is less ability to store metals than in tolerant genotypes.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00986797
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  • 40
    Digitale Medien
    Digitale Medien
    DNA reassociation kinetics and hybridization in different angiosperms (1980)
    Springer
    Plant systematics and evolution 136 (1980), S. 267-273 
    Details
    ISSN: 1615-6110
    Schlagwort(e): Angiosperms ; Daucus andPetroselinum (Apiaceae) ; Datura (Solanaceae) ; DNA ; reassociation kinetics ; DNA hybridization between varieties of the same species ; and genera of the same and of different families
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Reassociation kinetics ofDaucus carota andPetroselinum crispum (Apiaceae), andDatura innoxia (Solanaceae) are presented. Hybridization of3H-labelled DNA of two carrot cultivars indicate strong qualitative homologies of DNA sequences; nevertheless, certain quantitative differences in some Cotregions seem to exist. However, homologous sequences ofDaucus DNA with DNA ofDatura, and, suprisingly, even with DNA ofPetroselinum are very restricted: between 8% in the repeated regions and ca. 7–9% in the unique regions.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF01004631
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  • 41
    Digitale Medien
    Digitale Medien
    Immunocytochemical localization of myosin in the brush border region of the intestinal epithelium (1980)
    Springer
    Cell & tissue research 205 (1980), S. 163-166 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Myosin ; Intestinal epithelium ; Brush border ; Immunocytochemistry
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Myosin was localized in rat intestinal epithelium by means of indirect immunofluorescence and immunoelectron microscopy (unlabeled antibody peroxidase method), using a specific antibody to myosin from chicken gizzard. Immunoreactivity was localized in the apical cytoplasm, where it was concentrated along the rootlets of the microvillar filament bundles and in the terminal web. A model of microvillar contraction is proposed.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00234452
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  • 42
    Digitale Medien
    Digitale Medien
    Immunocytochemical localization of somatostatin in the brain of the lizard, Ctenosauria pectinata (1980)
    Springer
    Cell & tissue research 208 (1980), S. 499-505 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Somatostatin-immunoreactive elements ; Brain ; Lizard ; Immunocytochemistry
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The brain of the lizard, Ctenosauria pectinata, was studied light microscopically using an immunocytochemical staining method that is specific for neurohypophysial hormones and somatostatin. It was shown that the telencephalon and particularly the diencephalon contain somatostatin-producing perikarya, while somatostatinergic fibers occur in the entire brain. Similar to the situation in other vertebrates, somatostatin neurons in Ctenosauria pectinata form a population distinct from the neurohypophysial hormone-producing neurons. The small-sized somatostatin neurons were found in the cortex and the hypopallium of the telencephalon, and in two distinct clusters in the diencephalon: (1) ventral from, and partially overlapping with, the classical neurosecretory para ventricular nucleus; and (2) in the region of the infundibular (tuberal) nucleus. Somatostatin fibers were found among the classical neurosecretory fibers of the supraoptico-paraventricular system (tract, median eminence, neural lobe), near to and within the epiphysis, in the septum, in the vicinity of the tectum opticum and the cerebellum, and in the tegmentum.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00233881
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  • 43
    Digitale Medien
    Digitale Medien
    The cell types in the adenohypophysis of the South-American lungfish, Lepidosiren paradoxa, with special reference to immunocytochemical identification of the corticotropin-containing cells (1980)
    Springer
    Cell & tissue research 209 (1980), S. 147-160 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Pituitary ; Immunocytochemistry ; ACTH ; Lepidosiren
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The histological features and distribution of cell types in the distal lobe of Lepidosiren resemble those of Protopterus. Three “basophilic” cell types are described, whereas the identification of two acidophilic cell types is uncertain. In the intermediate lobe two cell types have been found. Anti-(1–24) ACTH IgG was used in the unlabeled antibody-enzyme method to identify corticotropin-containing cells in the adenohypophysis of Lepidosiren with light and electron microscopy. Corticotropin was demonstrated in cells of the distal lobe and the intermediate lobe. The staining reaction in the distal lobe is localized in the rostrally distributed lead-hematoxylin positive cells. At the ultrastructural level the immunoreaction in these distal lobe cells is localized on polymorphic granules ranging from 130 to 210 nm. Absorption experiments show that the immunoreactive cells in the distal lobe contain at least residues 1–3 and 14–17 of the naturally occurring corticotropin hormone, while the intermediate lobe cells contain α-MSH or at least residues 1–3 of ACTH. The plasma level of corticotropin was determined to be 71 ng/l by means of radioimmunoassay (RIA).
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00219931
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  • 44
    Digitale Medien
    Digitale Medien
    In vivo estrogen uptake by individual cell types of the rat anterior pituitary after short-term castration-adrenalectomy (1980)
    Springer
    Cell & tissue research 209 (1980), S. 167-175 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Pituitary gland ; Cell types ; Estrogen ; Autoradiography ; Immunocytochemistry
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary In vivo estrogen uptake was measured in five anterior pituitary cell types of the rat by a quantitative autoradiographic-immunocytochemical technique. In male and female rats that had been castrated and adrenalectomized for one day all five cell types showed nuclear concentration of label one hour after injection of 3H-estradiol. The order of labeling intensity was lactotropes 〉 somatotropes 〉 gonadotropes 〉 corticotropes 〉 thyrotropes. No significant overall sex difference in estrogen uptake was apparent although male pituitaries tended to take up slightly more. Physiological correlates to these data are discussed.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00219933
    Standort Signatur Erwartet Verfügbarkeit
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  • 45
    Digitale Medien
    Digitale Medien
    Long cytoplasmic processes in pancreatic polypeptide cells (1980)
    Springer
    Cell & tissue research 209 (1980), S. 365-370 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Pancreatic polypeptide (PP) cells ; Paracrine secretion ; Human pancreas ; Immunocytochemistry ; Pancreatic endocrine tumours
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Pancreatic polypeptide (PP) cells were studied in human endocrine pancreatic tumours and in normal human pancreata by immunohistochemical techniques and electron microscopy. The existence of long cytoplasmic processes was demonstrated both in tumours and normal tissue. These processes are in close contact with other endocrine cells or with acinar cells. This particular morphological aspect suggests that PP cells may control the function of other cells via paracrine secretion.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00234751
    Standort Signatur Erwartet Verfügbarkeit
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  • 46
    Digitale Medien
    Digitale Medien
    Intestinal calcium-binding protein (1980)
    Springer
    Cell & tissue research 212 (1980), S. 63-72 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Immunocytochemistry ; Brush border ; Epithelial cells ; Vitamin D ; Cell maturation
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The vitamin D-dependent calcium-binding protein (CaBP) was studied in relation to the age of the cell, in isolated epithelial cell populations removed from rat duodenum. Alkaline phosphatase and thymidine kinase activities were used as markers to characterize differentiated villus cells and undifferentiated (mitotically active) crypt cells, respectively. CaBP distribution along the length of the villus, as established by radioimmunoassay, appears as a gradient increasing from the crypt to the tip of the villus. CaBP concentration in cells is shown to be (i) negatively correlated with the thymidine kinase activity of cells, and (ii) positively correlated with the alkaline phosphatase activity of cells. This indicates that CaBP is absent in crypt cells and appears in differentiated cells with the development of the brush border. Thus CaBP, like alkaline phosphatase, can be considered as an indicator of enterocyte maturation. These data were also confirmed by studying the cellular localization of the protein. In addition both indirect immunofluorescence and immunoperoxidase staining methods reveal that antibody against CaBP decorates the terminal web, but not the microvilli of the brush border of mature absorptive cells. The results suggest that CaBP may act as a modulator of some Ca2+-mediated biochemical processes at the level of the enterocyte brush border.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00234033
    Standort Signatur Erwartet Verfügbarkeit
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  • 47
    Digitale Medien
    Digitale Medien
    Immunocytochemical identification of neural elements in the central nervous systems of a snail, some insects, a fish, and a mammal with an antiserum to the molluscan cardio-excitatory tetrapeptide FMRF-amide (1980)
    Springer
    Cell & tissue research 213 (1980), S. 21-27 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Immunocytochemistry ; FMRF-amide ; Central nervous system ; Neurohormone ; Neurotransmitter
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary With an antiserum to the molluscan cardio-excitatory tetrapeptide FMRF-amide neurons and/or nerve fibers were immunocytochemically identified in the central nervous systems of a snail (Lymnaea stagnalis), some insects (Leptinotarsa decemlineata, Periplaneta americana, Locusta migratoria, Pieris brassicae), a fish (Poecilia latipinna) and a mammal (mouse). The fact that immunoreactive material was observed in neurohaemal organs (corpora cardiaca of the insects) as well as in axon terminals ending on other neurons, seems to indicate that this peptide can function as a neurohormone and/or as a neurotransmitter. The results sustain the hypothesis that biologically active peptides have a wide distribution in the animal kingdom.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00236917
    Standort Signatur Erwartet Verfügbarkeit
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  • 48
    Digitale Medien
    Digitale Medien
    Immunocytochemical demonstration of met-enkephalin in the central nervous system of the domestic fowl (1980)
    Springer
    Cell & tissue research 213 (1980), S. 53-68 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Peptidergic neuroendocrine system ; Domestic fowl ; Metenkephalin system ; Immunocytochemistry
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary In the central nervous system of the male domestic fowl, met-enkephalin (ENK) immunoreactive perikarya and fiber tracts as well as extensive but sharply delimited fiber networks were visualized by means of the PAP technique. The most striking results were: (1) The demonstration of an association of ENK-containing structures with branchial nerves; (2) the spatial relationship of ENK-containing perikarya and fibers to somatostatin (SOM) and arginine-vasotocin (AVT)-immunoreactive systems; (3) the presence of dense and extensive ENK fiber networks within (a) the caudo-basal wall of the third ventricle and (b) the septal-preoptic area; in both regions mainly ENK fibers, but also SOM and AVT fibers, may cross to the contralateral side.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00236920
    Standort Signatur Erwartet Verfügbarkeit
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  • 49
    Digitale Medien
    Digitale Medien
    Do neural crest cells in the pancreas differentiate into somatostatin-containing cells? (1980)
    Springer
    Cell & tissue research 213 (1980), S. 293-299 
    Details
    ISSN: 1432-0878
    Schlagwort(e): Somatostatin ; Pancreas ; Neural crest cells ; Avian embryo ; Immunocytochemistry
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The possibility that the somatostatin cells are derived from the neurectoderm has been questioned in avian embryos. Isotopic and isochronic transplantations of the neural primordium from quail into chick embryos were made at the vagal level (somites 1 to 7). Quail and chick cells can be distinguished by the structure of their nucleus. The somatostatin cells were characterized immunocytochemically. In no case did quail cells showing the immunological reaction originate from the neural crest.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00234788
    Standort Signatur Erwartet Verfügbarkeit
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