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  • 1
    Digitale Medien
    Digitale Medien
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 84 (1998), S. 6725-6728 
    ISSN: 1089-7550
    Quelle: AIP Digital Archive
    Thema: Physik
    Notizen: Aging tests were performed for InP-based laser diodes heteroepitaxially grown on Si substrates. To define the degradation mode, we studied the change in the device characteristics and electroluminescence (EL) images during the aging tests. The degradation proceeds in a mode characterized by a gradual increase in the threshold current without a change in the current–voltage characteristics. During the aging, dark spot defects (DSDs) appear in the EL images, where no defects were observed initially. However, after a certain number of DSDs are generated, no more degradation occurs in the current–light-output characteristics and EL images. The correlation of the saturation behavior between the threshold current and DSD number is quite good, and strongly suggests that the device degradation is dominated by the development of nonradiative defects in the active layer. Judging from the saturation density of DSDs, we can assume that the origin of the nonradiative defects is closely related to the dislocation that remains in the heteroepitaxial layers. © 1998 American Institute of Physics.
    Materialart: Digitale Medien
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  • 2
    ISSN: 1432-8798
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Summary.  Bombyx mori cytoplasmic polyhedrosis virus (BmCPV) polyhedrin gene from natural mutant strain B, B2 and P was cloned and the amino acid sequence was compared with that of wild-type virus (strain H). Chimeric polyhedrin genes (8 types) containing only one site of mutation within the amino acid sequence were also constructed. Fifteen types of polyhedrin genes were introduced into a baculovirus expression vector and hexahedral, acicular, pyramidal, or amorphous polyhedra were formed in infected cells. These results demonstrated that the shape of polyhedra as well as the crystallization pattern of the polyhedrin could be changed by mutations at respectively N-terminal and C-terminal regions of BmCPV polyhedrin gene.
    Materialart: Digitale Medien
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  • 3
    Digitale Medien
    Digitale Medien
    s.l. ; Stafa-Zurich, Switzerland
    Materials science forum Vol. 269-272 (Jan. 1998), p. 327-332 
    ISSN: 1662-9752
    Quelle: Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
    Thema: Maschinenbau
    Materialart: Digitale Medien
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  • 4
    Digitale Medien
    Digitale Medien
    s.l. ; Stafa-Zurich, Switzerland
    Materials science forum Vol. 294-296 (Nov. 1998), p. 389-392 
    ISSN: 1662-9752
    Quelle: Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
    Thema: Maschinenbau
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 5
    Digitale Medien
    Digitale Medien
    s.l. ; Stafa-Zurich, Switzerland
    Materials science forum Vol. 269-272 (Jan. 1998), p. 333-338 
    ISSN: 1662-9752
    Quelle: Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
    Thema: Maschinenbau
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 6
    Digitale Medien
    Digitale Medien
    Springer
    Cellular and molecular life sciences 54 (1998), S. 928-934 
    ISSN: 1420-9071
    Schlagwort(e): Key words. Genetic epidemiology; dementia; apolipoprotein E; Alzheimer's disease; polymorphisms; tau protein; amyloid protein; transgenic mice; susceptibility genes.
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Abstract. Epidemiologic and laboratory results consistently implicate the APOE gene in the pathogenesis of late-onset Alzheimer's disease (AD) the ε4 allele increases risk in a dose-dependent fashion, while ε2 confers protection. Individuals are susceptible for AD in varying degrees depending on which combination of APOE alleles has been inherited, APOE promoter polymorphism and other factors. Deposition of both senile plaques and neurofibrillary tangles, the pathologic hall marks of AD, are enhanced by ε4 from the earliest lesions onward – diffuse plaques consisting of Aβ 1 – 42 and neurofibrillary tangles in the entorhinal cortex. Transgenic APOE mice carrying an APP mutation and 0, 1 or 2 copies of APOE showed dose-related increases in plaque deposition in the hippocampus and cortex, a clear indication that APOEp promotes Aβ deposition. The presence of each additional APOE ε4 allele leads to an earlier onset of the histopathological process of about 1 decade, on average. The association of both types of AD-related changes with the occurrence of ε4 suggests that the APOE polymorphism causally contributes to the pathogenesis of AD.
    Materialart: Digitale Medien
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  • 7
    ISSN: 1432-0533
    Schlagwort(e): Key words Corticobasal degeneration ; Progressive ; supranuclear palsy ; Astrocytic plaques ; Tufts of ; abnormal fibers ; Gallyas-Braak silver staining
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract Corticobasal degeneration (CBD) and progressive supranuclear palsy (PSP) are characterized by their unique clinical features and neuronal pathology. Although astrocytic plaques and tufts of abnormal fibers have been suggested to be specific histopathologic markers, recent studies have revealed significant clinicopathologic overlap between CBD and PSP. Based on the distinctive camera lucida profile of astrocytic inclusions on Gallyas-Braak silver staining, we found that astrocytic plaques and tufts of abnormal fibers did not coexist in the same patient among 30 cases of clinically diagnosed CBD, PSP and atypical Parkinson’s disease. Using Tau immunohistochemistry it was difficult to verify the absence of tufts of abnormal fibers. A morphometric analysis revealed that the two groups classified by the presence or absence of astrocytic plaques and tufts of abnormal fibers exhibited significant differences in the density of ballooned neurons and neurofibrillary tangles and degeneration of the subcortical nuclei. Assessment using the NINDS neuropathologic criteria revealed that the cases with astrocytic plaques and tufts of abnormal fibers closely correspond to CBD and typical PSP, respectively. In addition, the cases lacking either of these two astrocytic inclusions had atypical PSP according to the NINDS criteria, and were associated with novel tau-positive astrocytes (spiny astrocytes). We thus conclude that astrocytic plaques and tufts of abnormal fibers are highly characteristic structures for CBD and typical PSP, respectively. We emphasize the importance of strict differentiation between different astrocytic inclusions not only for diagnosis, but also for further studies for elucidation of their role in the disease mechanisms of CBD and PSP.
    Materialart: Digitale Medien
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  • 8
    ISSN: 1432-1041
    Schlagwort(e): Key words Y-25510 ; Cytokines
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie , Medizin
    Notizen: Abstract Objective: Y-25510 was administered by means of an intravenous drip infusion to healthy adult male volunteers at a dose of 40, 80 or 160 mg in a single-dose study, and at a dose of 160 mg once a day for 7 days in a multiple-dose study. Results: Serum levels of interleukin (IL)-1β, IL-6 and IL-10 were significantly increased, but there was no change in leukocyte and platelet counts. The peak serum concentration of IL-1β was nearly maximum at the single doses of 40 and 80 mg, and at the multiple dose of 160 mg per day. The peak serum concentration of IL-6 increased in a dose-dependent manner at a dose of 40 mg or more. For the multiple-dose study, the serum level of IL-10, which remained unchanged in the placebo group, began to increase in the Y-25510 group following the maximum serum level of IL-1β and IL-6. There were no clinically relevant differences in body temperature and blood pressure after the administration of Y-25510. Conclusion: These findings that leukocyte and platelet counts never increased, despite the increment of the IL-1β and IL-6 production after the administration of Y-25510, may be explained in part by the negative feedback mechanism induced by IL-10.
    Materialart: Digitale Medien
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  • 9
    ISSN: 1432-1084
    Schlagwort(e): Key words: Lung cancer ; Progressive massive fibrosis ; Pneumoconiosis ; MRI
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract. We report the MRI features and correlative pathologic findings of a lung cancer in a patient with progressive massive fibrosis (PMF). In this case, MRI was able to distinguish the lung cancer as a high signal intensity area, and the fibrotic mass as a low signal intensity area, on both T1-weighted and T2-weighted images when compared with muscle. MRI is potentially useful in distinguishing cancer tissue from PMF in patients with pneumoconiosis.
    Materialart: Digitale Medien
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  • 10
    ISSN: 1432-0584
    Schlagwort(e): Key words Acute lymphoblastic leukemia ; Complication ; Disseminated intravascular coagulation ; CD34
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract  A high frequency of disseminated intravascular coagulation (DIC) in adult acute lymphoblastic leukemia (ALL) has been reported; however, its clinical relevance and characteristics have not been fully determined. We studied 67 adults with newly diagnosed ALL between 1982 and 1996 to clarify these questions. DIC was diagnosed in ten of 64 patients (16%) who underwent coagulation study at presentation and in 14 of 40 patients (35%) screened for DIC within 7 days after starting remission induction therapy. Overall, 24 of 67 patients (36%) had DIC during this period. Hemorrhagic symptoms were generally mild, while two patients required red blood cell transfusions. Patients who developed DIC had higher white blood cell counts and more frequently a palpable spleen than those who did not. There was no difference in age, French-American-British subtype, karyotype, immunophenotype, lactate dehydrogenase level, percentage of blasts in bone marrow, or frequency of lymphadenopathy or hepatomegaly between patients who had DIC and those who did not. Fibrinolysis tended to be milder in DIC complicating ALL than in that complicating acute promyelocytic leukemia; however, there was no difference in other coagulation parameters between these two subtypes. An etiological link between CD34 expression in common ALL patients and DIC was suggested.
    Materialart: Digitale Medien
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