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  • 1
    Digitale Medien
    Digitale Medien
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 91 (2002), S. 2729-2736 
    ISSN: 1089-7550
    Quelle: AIP Digital Archive
    Thema: Physik
    Notizen: The Brillouin light scattering technique is used to observe thermally excited acoustic phonons in backscattering geometry in a transparent, 1.8 μm thick diode sputtered c-BN film. The Rayleigh mode at the film surface and the quasilongitudinal bulk mode were detected under various angles of light incidence. The angular dependent phase velocity of the bulk wave provides evidence for an elastic anisotropy of the film material. Complete descriptions of the elastic properties are presented, assuming either isotropic or hexagonal film symmetry. The reduction of the film stiffness in comparison to the single crystal and the origin of the elastic anisotropy of c11/c33(approximate)4/5, where c11 and c33 are the respective extensional stiffness constants parallel and perpendicular to the film, is discussed. Both effects are predominantly caused by sp2-bonded material and a structured film growth. © 2002 American Institute of Physics.
    Materialart: Digitale Medien
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  • 2
    Digitale Medien
    Digitale Medien
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 87 (2000), S. 6397-6399 
    ISSN: 1089-7550
    Quelle: AIP Digital Archive
    Thema: Physik
    Notizen: Individual layers of Ni0.8Fe0.2, Ni0.8Fe0.13Co0.07, TaN, and CrSi, and a full magnetic random access memory stack consisting of NiFeCo/CoFe/Cu/CoFe/NiFeCo/TaN/CrSi multilayers, were etched in high density Cl2/Ar plasmas either with or without concurrent ultraviolet (UV) illumination. Under optimized conditions, etch rate enhancement up to a factor of 5 was obtained for NiFeCo, TaN, and CrSi with UV illumination; whereas the etch rate of NiFe was retarded. Post-etch cleaning with H2 or SF6 plasmas or H2O rinsing was necessary in all cases in order to prevent corrosion of the metal layers from chlorinated etch residues. © 2000 American Institute of Physics.
    Materialart: Digitale Medien
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  • 3
    ISSN: 1365-2222
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Medizin
    Notizen: Background The cause of the chronic inflammation in atopic keratoconjunctivitis (AKC), the ocular manifestation of atopic eczema/dermatitis syndrome, is largely unknown.Objective To investigate the possibility that microorganisms may be important in the inflammatory activity in AKC.Methods Fifteen patients with AKC participated in the study. The presence of aerobic bacteria and fungi was related to the severity of clinical signs, the numbers of inflammatory cells in tears and conjunctival biopsies, and the concentration of various cytokines in tears. In addition, serological evidence for IgE sensitization to Staphylococcus aureus B antigen and Malassezia sympodialis antigen was investigated. Twelve healthy subjects were included for control purposes.Results The patients exhibited moderate clinical signs of AKC. No relation was found between the severity of AKC and the presence of microorganisms, despite the fact that S. aureus was frequently isolated. AKC patients showed significantly higher levels of IFN-γ, TNF-α (tumour necrosis factor-α), IL-2, IL-4, IL-5 and IL-10 than controls. An association was found between conjunctival signs and the levels of all cytokines except IL-5.Conclusion We found no evidence to suggest that periocular and ocular microcolonization are related to inflammatory parameters in AKC. However, confirmation of the present results in a longitudinal study with repeated clinical examinations and samplings in the same individual is required before the contribution of S. aureus to on-going inflammation in AKC can be dismissed.
    Materialart: Digitale Medien
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  • 4
    ISSN: 1365-2559
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Medizin
    Notizen: Aims:  Maspin is a recently described member of the serpin family or protease inhibitors that is known to be a tumour suppressor gene product. Loss of maspin expression has been found in most breast cancer cases and is correlated with cell motility and tumour invasiveness. However, its precise role in human breast cancer remains to be discovered. We aimed to evaluate the role of maspin in early-stage breast cancer.Methods and results:  We analysed the expression of maspin in 192 stage I and II primary breast cancers by immunohistochemistry. Of these cases, 34.4% showed maspin expression. Maspin expression was more frequently found in invasive ductal carcinoma (36.4%) than in invasive lobular carcinoma (7.1%). High maspin expression was demonstrated in breast cancers showing high histological grade or lymphocyte-rich stroma (P 〈 0.05). Maspin expression was not associated with overall and disease-free survival rate of breast cancer.Conclusions:  The results indicate that different biological mechanisms may be responsible for maspin expression in histologically distinct types of breast cancer. Our survey suggests that maspin expression in breast cancer might have a compensatory role rather than prognostic one.
    Materialart: Digitale Medien
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  • 5
    ISSN: 1433-0563
    Schlagwort(e): Schlüsselwörter Prostataspezifisches Antigen ; Humanes Kallikrein 2 ; Molekulare Formen ; Prostatakarzinom ; Benigne Prostatahyperplasie ; Key words Prostate-specific antigen ; Human kallikrein 2 ; Molecular forms ; Prostate cancer ; Benign prostatic hyperplasia
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Beschreibung / Inhaltsverzeichnis: Abstract Prostate-specific antigen (PSA) is the most useful marker in the early detection of prostate cancer and in the monitoring of patients with this diagnosis. Molecular forms of PSA and human kallikrein 2 (hK2) have been used to discriminate between benign prostatic hyperplasia and prostate cancer, as well as for the detection of prostate cancer within the gray zone of PSA. In this respect, a literature survey on the diagnostic validity of free PSA (fPSA) related to total PSA (tPSA), PSA bound to α1-antichymotrypsin (ACT-PSA), and complexed PSA (cPSA) is given together with our own results. The ratio of fPSA/tPSA has been shown to improve both sensitivity and specificity of prostate cancer diagnosis based on tPSA measurements. The number of biopsies can be reduced in the total PSA range of 4–10 μg/l. Furthermore, carcinomas can be detected in patients with PSA values less than 4 μg/l. ACT-PSA or cPSA alone and the calculated derivatives are not superior in their discriminatory power compared with tPSA and the fPSA% value. The other molecular PSA forms and hK2 are still objects of research and their diagnostic significance needs to be evaluated in more extensive clinical trials.
    Notizen: Zusammenfassung Das prostataspezifische Antigen (PSA) ist die wichtigste Kenngröße in der Diagnostik und Therapieüberwachung des Prostatakarzinoms. Zur besseren Abgrenzung zwischen benigner Prostatahyperplasie (BPH) und Prostatakarzinom, aber auch zur Früherkennung des Prostatakarzinoms haben sich die molekularen Formen des PSA und neuerdings auch das humane Kallikrein 2 (hK2) als wertvolle Entscheidungshilfen erwiesen. Es wird eine Literaturübersicht über bisher vorliegende Informationen zur Aussagekraft des freien PSA (fPSA) in Relation zum Gesamt-PSA (tPSA), des an α1-Antichymotrypsin gebundenen PSA (ACT-PSA) und des komplexierten PSA (cPSA) zusammen mit eigenen Resultaten gegeben. Der Quotient fPSA/tPSA (fPSA%) hat sich bereits als eine wichtige Entscheidungsgröße in der urologischen Praxis etabliert, mit der Sensitivität und Spezifität der Prostatakarzinomdiagnostik verbessert werden. Die Zahl von Prostatastanzbiopsien im tPSA-Bereich 4–10 μg/l kann damit reduziert und bei tPSA-Werten 〈4 μg/l können zusätzlich unerkannte Karzinompatienten identifiziert werden. Ein diagnostischer Vorteil der alleinigen Bestimmung des gebundenen PSA bzw. der entsprechenden Quotienten (ACT-PSA/tPSA oder cPSA/tPSA) im Vergleich zum fPSA% konnte bisher nicht sicher nachgewiesen werden. Die Bestimmungen der anderen molekularen PSA-Formen und des hK2 sind noch weitgehend Gegenstand der Forschung bzw. erfordern noch entsprechende klinische Evaluierungen.
    Materialart: Digitale Medien
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  • 6
    ISSN: 1433-0563
    Schlagwort(e): Schlüsselwörter Tumor-M2-Pyruvatkinase (TUM2-PK) ; Nierenzellkarzinom ; Keywords Tumor M2 pyruvate kinase ; Renal cell carcinoma
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Beschreibung / Inhaltsverzeichnis: Abstract Tumor cell metabolism is characterized by a high rate of aerobic glycolysis. The metabolic differences require changes in glycolytic enzyme activities and isoenzyme patterns. The inactive form of the M2 pyruvate kinase (Tu M2-PK) is specifically expressed in tumor cells and has been detected immunohistochemically in tumor tissue but also in peripheral blood of patients with different malignant tumors. In this study, Tu M2-PK in the plasma of patients with renal cell carcinoma (RCC) was compared with healthy volunteers. Tu M2-PK was quantified with a commercially available enzyme linked immunosorbent assay (ELISA) kit. Using the ELISA kit, plasma probes of 57 healthy individuals were compared to 63 patients with RCC (51 patients with non-metastatic RCC, 12 patients with metastatic RCC). Statistical analysis was performed with the non-parametric ANOVA test according to Kruskal-Wallis. In patients with renal cell carcinoma, Tu M2-PK was significantly higher than in healthy volunteers. For organ-defined, non-metastatic tumors, sensitivity was only 27.5%, if the 95% reference values of the control group were used for discrimination. The differences were more pronounced in patients with metastatic disease. Tu M2-PK was significantly enhanced compared to healthy controls, but also to the group with non-metastatic disease, the sensitivity was 66.7%. Our data show that Tu M2-PK has no impact as an unspecific marker for the diagnosis of renal cell carcinoma. This is especially relevant to organ-defined, non-metastatic RCC. In advanced metastatic disease, a potential importance as a parameter for treatment control in palliative therapeutic approaches can be assumed, and warrants further investigations.
    Notizen: Zusammenfassung In Tumorzellen ist der Stoffwechsel durch eine erhöhte Rate aerober Glykolyse gekennzeichnet. Die tumorspezifischen metabolischen Eigenschaften setzen Veränderungen der Aktivitäten und Isoenzymmuster glykolytischer Enzyme voraus. Die inaktive Form der M2-Pyruvatkinase (TUM2-PK) wird spezifisch in Tumorzellen exprimiert und konnte immunhistochemisch im Tumorgewebe, aber auch im peripheren Blut von Patienten mit verschiedenen Malignomen nachgewiesen werden. In der vorliegenden Studie haben wir die TUM2-PK im Plasma von Patienten mit Nierenzellkarzinomen (NZK) analysiert und mit gesunden Probanden verglichen. Die TUM2-PK wurde mit einem kommerziellen Enzyme-linked-immunosorbent-assay-(ELISA)-Kit quantifiziert. Das Plasma von 57 Gesunden wurde mit dem Plasma von 63 Patienten mit einem Nierenzellkarzinom vor Operation (51 Patienten mit nichtmetastasierten NZK, 12 Patienten mit metastasierten NZK) verglichen. Die statistische Analyse erfolgte mit dem nichtparametrischen ANOVA-Test nach Kruskal-Wallis. Patienten mit einem NZK wiesen statistisch signifikant höhere TUM2-PK-Werte auf als gesunde Probanden. Für organbegrenzte, nichtmetastasierte Tumoren betrug die Sensitivität jedoch nur 27,5%, wenn die 95%igen Referenzgrenzen der Kontrollgruppe als Diskriminationswert zugrundegelegt wurden. Der Unterschied war deutlicher bei Patienten mit einer metastasierten Erkrankung. Hier war die TUM2-PK signifikant im Vergleich zur Kontrollgruppe, aber auch im Vergleich zur Gruppe mit nichtmetastasierten NZK erhöht und die Sensitivität betrug 66,7%. Nach unseren Untersuchungen ist die TUM2-PK als unspezifischer Marker für die Diagnostik des Nierenzellkarzinoms nicht geeignet. Dies gilt insbesondere für organbegrenzte, nichtmetastasierte Nierenzellkarzinome. In fortgeschrittenen, metastasierten Stadien ergibt sich potentiell eine Bedeutung als Parameter zur Verlaufskontrolle bei palliativen Therapieansätzen. Dies wird z.Z. an unserer Klinik geprüft.
    Materialart: Digitale Medien
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  • 7
    Digitale Medien
    Digitale Medien
    Springer
    Applied microbiology and biotechnology 53 (2000), S. 201-208 
    ISSN: 1432-0614
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Werkstoffwissenschaften, Fertigungsverfahren, Fertigung
    Notizen: Abstract  Using high-cell-density culture of Escherichia coli under the control of an l-arabinose promoter (ParaB), several factors affecting the production of recombinant protein and the formation of inclusion bodies were studied. The inducer, l-arabinose, showed a maximal induction level above 10.7 mM in the final concentration. The concentration of inducer also affected the partition of interferon-α (IFN-α) into the soluble form and inclusion bodies. Induction kinetics of the rate of accumulation of IFN-α on the ParaB promoter showed a slower rate than those of other promoter systems, for example T7, lac or tac. These innate characteristics of ParaB enabled cells to grow continuously in spite of the metabolic burden induced by the expression of foreign protein. The duration time of induction could control the expression of both soluble and insoluble protein. The ratio of yeast extract to glycerol (N/C ratio) in feeding media significantly affected both the production level of recombinant protein and inclusion body formation. The reason for decreasing specific bioactivity during induction can be explained by the increased proportion of inclusion bodies in the total expressed IFN-α.
    Materialart: Digitale Medien
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  • 8
    Digitale Medien
    Digitale Medien
    Springer
    Applied microbiology and biotechnology 54 (2000), S. 521-527 
    ISSN: 1432-0614
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Werkstoffwissenschaften, Fertigungsverfahren, Fertigung
    Notizen: Abstract A Clostridium thermocellum gene, xynX, coding for a xylanase was cloned and the complete nucleotide sequence was determined. The xylanase gene of Clostridium thermocellum consists of an ORF of 3261 nucleotide encoding a xylanase (XynX) of 1087 amino acid residues (116 kDa). Sequence analysis of XynX showed a multidomain structure that consisted of four different domains: an N-terminal thermostabilizing domain homologous to sequences found in several thermophilic enzymes, a catalytic domain homologous to family 10 glycosyl hydrolases, a duplicated cellulose-binding domain (CBD) homologous to family IX CBDs, and a triplicated S-layer homologous domain. A deletion mutant of xynX having only the catalytic region produced a mutant enzyme XynX-C which retained catalytic activity but lost thermostability. In terms of half-life at 70 °C, the thermostability of XynX-C was about six times lower than that of the other mutant enzyme, XynX-TC, produced by a mutant containing both the thermostabilizing domain and the catalytic domain. The optimum temperature of XynX-C was about 5–10 °C lower than that of XynX-TC.
    Materialart: Digitale Medien
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  • 9
    ISSN: 1572-8986
    Schlagwort(e): ICP ; compound semiconductors ; interhalogens
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Technik allgemein
    Notizen: Abstract High-density plasma etching of GaAs, GaSb, and AlGaAs was performed inICl/Ar and IBr/Ar chemistries using an Inductively Coupled Plasma (ICP)source. GaSb and AlGaAs showed maxima in their etch rates for both plamachemistries as a function of interhalogen percentage, while GaAs showedincreased etch rates with plasma composition in both chemistries. Etchrates of all materials increased substantially with increasing rf chuckpower, but rapidly decreased with chamber pressure. Selectivities 〉10 forGaAs and GaSb over AlGaAs were obtained in both chemistries. The etchedsurfaces of GaAs showed smooth morphology, which were somewhat better withICl/Ar than with IBr/Ar discharge. Auger Electron Spectroscopy analysisrevealed equirate of removal of group III and V components or thecorresponding etch products, maintaining the stoichiometry of the etchedsurface.
    Materialart: Digitale Medien
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  • 10
    ISSN: 1572-8986
    Schlagwort(e): ICP ; compound semiconductors ; interhalogens
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Technik allgemein
    Notizen: Abstract A parametric study of Inductively Coupled Plasma (ICP) etching of InP, InSb, InGaP, and InGaAs has been carried out in ICl/Ar and IBr/Ar chemistries. Etch rates in excess of 3.1 for InP, 3.6 for InSb, 2.3 for InGaP, and 2.2 μm/min for InGaAs were obtained in IBr/Ar plasmas. The ICP etching of In-based materials showed a general tendency: The etch rates increased substantially with increasing ICP source power and rf chuck power in both chemistries, while they decreased with increasing chamber pressure. The IBr/Ar chemistry typically showed higher etch rates than ICl/Ar, but the etched surface morphologies were fairly poor for both chemistries.
    Materialart: Digitale Medien
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