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  • 1990-1994  (6)
  • 1985-1989  (12)
  • 1960-1964  (3)
  • 1
    Digitale Medien
    Digitale Medien
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 58 (1985), S. 2651-2654 
    ISSN: 1089-7550
    Quelle: AIP Digital Archive
    Thema: Physik
    Notizen: It can generally be considered that an actual contact makes an angle with the extension of the contact surface because the tip of a contact element is convex in shape (macroscopically) and has surface roughness (microscopically). The effect of this angle on constriction resistance and contact resistance for a point contact is analyzed theoretically by solving Laplace's equation subject to boundary conditions determined by a modeled morphology of the contact. The analysis leads to the modified formulas for the constriction resistance and the contact resistance, which show that the effect cannot always be neglected and that the contact model with space angle is useful.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 2
    Digitale Medien
    Digitale Medien
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 69 (1991), S. 2987-2997 
    ISSN: 1089-7550
    Quelle: AIP Digital Archive
    Thema: Physik
    Notizen: It has been clarified in an earlier work [Y. Sano, J. Appl. Phys. 65, 3857 (1989)] that the locations of attenuating peaks in smooth strain, particle velocity, and stress profiles in a smooth plane-wave front differ, that is, the order of peak precedence is stress, particle velocity, and strain. As a result of the precedence order, the wave front composed of elementary waves such as a contraction wave C, mesocontraction waves I and II, and a vice-rarefaction wave R was formed. That the process is degraded by another rarefaction wave Rb which first follows the wave R, and then outruns the waves R, II, and I in sequence, has also been proved. [Y. Sano, J. Appl. Phys. 67, 4072 (1990)]. After the completion of the degradation process, the wave front, i.e., the wave C, may attenuate little, but steepen. This paper extends the process under consideration to include the steepening process during which the wave C approaches a steady state. In addition to this extension, stationary phenomena in strain, particle velocity, and stress-time profiles are shown to be able to take place in the degradation process. It is one of the main purposes of this paper to show through the phenomena that the response caused by the wave fronts during the process will be unsteady and nonequilibrium. Furthermore, universal properties of the stress-particle velocity paths are clarified. The properties involve concavity or convexity of the path curves produced by the waves C, I, II, and R. Universal properties of the stress-strain paths such as concavity, convexity, or inflection of the path curves by the waves C, I, II, and R are also clarified. Through the behavior of the stress-particle velocity and stress-strain paths having the properties mentioned above, it is also shown that the response caused by the waves will be unsteady and nonequilibrium. The stationary phenomena, the universal properties, and the stress-particle velocity and stress-strain behaviors are compared with the previous experiments and computational data. Another main purpose of this paper is to confirm through comparison the occurrence of the elementary waves and the degradation process in the experiments.
    Materialart: Digitale Medien
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  • 3
    ISSN: 1365-2222
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Medizin
    Notizen: There is increasing evidence for the role of basophils in the pathogenesis of bronchial asthma. To examine the presence of basophils in the airways of patients with fatal asthma by immunohistochemistry, we stained lung tissues from four post-mortem cases who had died from severe asthmatic attacks and four controls with a monoclonal antibody raised against tryptase (AA-1) and anti-IgE. Mast cells and basophils were identified in the bronchioles as A A-1- and anti-IgE-positive cells, and anti-IgE-posilive cells, respectively. Airway mast cells were found beneath the basemenl membrane, near blood vessels in the submucosa, and adjacent to the submucosal glands, and scattered throughout the muscle bundles. There was a significant increase of mast cells in the asthma group compared with the control group (203.5 ± 84.6/mm2, mean ± s. d. vs 37.7 ± 8.7/mm2, P 〈 0.05, n= 4). In contrast, basophils were observed in the airway lumen, in the bronchial epithelium and in the submucosa. The number of basophils in the bronchioles was 81.8 ± 55.5/mm2 (n= 4); however, basophils were not found at all in the airways of the control group. Although eosinophils, B lymphocytes and macro-phages bear low affinity IgE receptors and could react with anti-IgE, the location of these cells in the close sections did not correspond closely with basophils. The presence of basophils in lung tissues obtained from fatal asthma patients supports the view that basophils play a role in the pathogenesis of bronchial asthma.
    Materialart: Digitale Medien
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  • 4
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    British journal of dermatology 123 (1990), S. 0 
    ISSN: 1365-2133
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Medizin
    Notizen: A 57-year-old woman with T-cell lymphoma developed subcutaneous tumours and panniculitis and also a progressive pancytopenia.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 5
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    Annals of the New York Academy of Sciences 540 (1988), S. 0 
    ISSN: 1749-6632
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Allgemeine Naturwissenschaft
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 6
    Digitale Medien
    Digitale Medien
    Springer
    Theoretical and applied genetics 86 (1993), S. 1038-1042 
    ISSN: 1432-2242
    Schlagwort(e): Oryza sativa ; Indica-Japonica hybrid ; Hybrid sterility ; Female sterility
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract The genetic model for hybrid sterility that an allelic interaction at the S 5 locus induces the abortion of megaspores has been proposed as partial clarification of the wide compatibility in Asian rice cultivars; this model predicts the presence of an egg-killer. The present study was carried out in order to confirm that the proposed S 5 i allele acts as an egg-killer against its counterpart, the S 5 j allele, in the Indica-Japonica hybrid. A conspicuous feature of an egg-killer is the high rate of its transmission into the progeny through the egg. Backcrossing experiments were conducted using the Indica-Japonica hybrid in which the S 5 i and S 5 j alleles were assumed to be involved. Although an egg-killer was easily identified by these backcross experiments, it was not detected in the Indica-Japonica hybrid, which suggests that the proposed genetic mechanism for hybrid sterility in Asian rice should be viewed with caution.
    Materialart: Digitale Medien
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  • 7
    Digitale Medien
    Digitale Medien
    Springer
    Journal of molecular evolution 38 (1994), S. 132-137 
    ISSN: 1432-1432
    Schlagwort(e): Plant SINE ; retroposon ; Rice evolution ; wx locus ; Oryza sativa ; PCR ; Repetitive sequences
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract A new type of plant retroposon, p-SINE1, has been found in the wx locus of rice (Oryza sativa). It has some structural characteristics similar to those of mammalian SINEs, such as members of the Alu or Bl family. In order to estimate the time at which the integration of p-SINE1 into a single locus occurred during rice evolution, we examined the distribution of two members of p-SINE1 in several species of the Oryza genus by the polymerase chain reaction (PCR). We found that one member of p-SINE1 (p-SINE1-r2) in the ninth intron of the wx + gene was present only in two closely related species, O. sativa and O. rufipogon, and was not present in the other species carrying the AA genome within the Oryza genus. This result indicates that p-SINE1-r2 was integrated into the wx locus after O. sativa and O. rufipogon had diverged from other species with the AA genome. In contrast to p-SINE1-r2, another member (p-SINE1-rl) located in the untranslated 5′-region of the wx + gene was present not only in all species with the AA genome but also in species with a different genome (CCDD). This result suggests that p-SINE1-rl was integrated into that position prior to the genomic divergence. Thus, it appears that each member of p-SINE1 was retroposed at a specific site at a different time during rice evolution.
    Materialart: Digitale Medien
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  • 8
    ISSN: 1432-0568
    Schlagwort(e): Serotonin ; Substantia nigra ; Mammals (rat, cat, Macaca fuscata) ; Immunohistochemistry ; Ultrastructure
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Summary The distribution of serotonin-containing nerve fibers in the substantia nigra of the rat, cat and monkey was studied with a highly sensitive peroxidase-antiperoxidase immunohistochemical method. Serotonin fibers in the substantia nigra of all species consisted of fine varicose fibers and formed a fine network. In the zona compacta of all species, serotonin fibers were sparsely distributed. In the zone reticularis of the rat and cat, these fibers were densely distributed and their distributional pattern was almost uniform, while in the monkey such fibers were unevenly distributed and high and low dense areas were intermingled. In the pars lateralis of all species, serotonin fibers were diffusely distributed, and the distributional density was much higher in the cat and monkey than in the rat. Immunoelectron-microscopic studies further revealed that a majority of the labeled varicosities in the rat substantia nigra were in close apposition to peridendritic axon terminals and were also free in the neuropil; occasionally they exhibited symmetrical synapses of “en passant” type with non-immunoreactive dendrites or somata. Our results support a functional significance of serotonergic regulation of the substantia nigra in mammals.
    Materialart: Digitale Medien
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  • 9
    ISSN: 1432-0568
    Schlagwort(e): Dopamine-β-hydroxylase ; Anterior column ; Ultrastructure ; Immunohistochemistry ; Rat
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Summary Dopamine-β-hydroxylase (DBH) immunohistochemistry was used to demonstrate the noradrenergic fibers and terminals in the anterior column of the rat lumbosacral spinal segments. PAP-positive varicose fibers were widely distributed in the gray matter with preferential accumulation in the nuclear regions containing motoneurons involved in the contraction of perineal striated muscles. Unmyelinated DBH fibers were composed of nodular enlargements (varicosities, 0.4–3.0 μm in diameter) and very fine, short intervals (intervaricose segments, 0.1–0.2 μm in diameter and 1.0–4.0 μm in length). DBH-positive dense products were electron microscopically often confined within small granular particles and less frequently within large granules. Additionally, in order to characterize the innervation pattern of noradrenergic fibers on dendritic bundles organized in the motoneuronal pools innervating the pelvic small muscles, semi-quantitative analysis was done in the area of the dorsolateral nucleus endowed with especially well-developed dendritic bundles. DBH terminals contacting with unreactive dendrites were more common (67.9%) than those with neuronal somata (15.1%), and the remainder (17%) had no contacts with surrounding neuronal elements. Furthermore, specialized synaptic formations were observed in only 20.1% of these nodules. The results suggest that bulbospinal descending noradrenergic neuron systems influence the functioning of pelvic muscles principally via the neuronal contacts with dendritic bundles in the spinal cord.
    Materialart: Digitale Medien
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  • 10
    ISSN: 1432-0568
    Schlagwort(e): Serotonin ; Striatum ; Globus pallidus ; Mammals (rat, cat,Macaca fuscata) ; Immunohistochemistry
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Summary The distribution of serotonin-containing nerve fibers in the corpus striatum of the rat, cat and monkey was studied with modified peroxidase-antiperoxidase method using serotonin antiserum without any pretreatment. In the neostriatum (caudate nucleus and putamen) of all mammalian species investigated, the immunoreactive fibers were distinct varicose fibers in a fine network. The concentration of these fibers was high in the ventral, medial and caudal neostriatum. Especially in the area bounded by the globus pallidus, serotonin fibers were abundant and compactly arranged along the nucleus. In this area of the monkey, a few thick fibers (tract fibers) were intermingled; they ran along the lateral medullary lamina. Such tract fibers were also observed outside the medial medullary lamina and in the central portion of the medial pallidal segment. The paleostriatum (globus pallidus and entopeduncular nucleus) of the rat and cat as well as the medial pallidal segment of the monkey was diffusely innervated with serotonin fibers composed of numerous varicosities and fine intervaricose segments, while in the lateral pallidal segment of the monkey, the distribution of fibers was scantly and partial. Our results hint at the morphological basis of the serotonergic regulation of the extrapyramidal system in mammals.
    Materialart: Digitale Medien
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