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  • 1
    Digitale Medien
    Digitale Medien
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 67 (1995), S. 1444-1446 
    ISSN: 1077-3118
    Quelle: AIP Digital Archive
    Thema: Physik
    Notizen: We have systematically studied the dependence of the electrical properties of Si-doped (311)A GaAs on the growth conditions in molecular beam epitaxy and have established a phase diagram for the conduction type as functions of the growth temperature and the V4/III flux ratio. A sharp boundary is observed for the transition between the p- and n-type conduction, on both sides of which the activation efficiency of Si is close to unity. Furthermore, it is found that, in contrast to the case of the (111)A GaAs, the conduction-type conversion in Si-doped (311)A GaAs does not show a clear correlation with the macroscopic surface morphology, suggesting that the mechanism for the conduction-type conversion in Si-doped (311)A GaAs is different from that for the (111)A orientation. © 1995 American Institute of Physics.
    Materialart: Digitale Medien
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  • 2
    ISSN: 1365-2036
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Medizin
    Notizen: Background : A decrease in pepsinogen and gastrin levels 1–3 months after Helicobacter pylori eradication is well known. However, few data are available on the long-term progression of these decreases beyond 1 year after eradication, and there has been no investigation into whether pepsinogen and gastrin levels return to normal levels as defined by data from H. pylori-negative patients with dyspepsia.Aim : We studied the effect of H. pylori eradication on pepsinogen and gastrin levels for more than 1 year, and compared levels to those in H. pylori-negative patients with dyspepsia. We also investigated the effect of H. pylori eradication on the course of atrophic corpus gastritis as reflected by histology, and on PGI levels and PG I/II ratio.Methods : We enrolled 172 H. pylori-positive patients with dyspepsia who had undergone successful eradication therapy of more than 1 year's duration and 101 non-treated H. pylori-negative patients with dyspepsia. H. pylori status was assessed at entry and at each endoscopy after eradication by culture, histological results, the rapid urease test and the urea breath test. In both groups, patients were evaluated for fasting serum pepsinogen I and II and gastrin using a radioimmunoassay technique, and underwent detailed histological assessment according to the updated Sydney System.Results : In the H. pylori-negative patients, mean serum pepsinogen I and II, I/II ratio and gastrin levels were 52.6 ± 20.8 ng/mL, 9.2 ± 4.2 ng/mL, 6.0 ± 1.7 and 53.5 ± 29.2 pg/mL, respectively. In H. pylori-positive patients with long-term eradication, pepsinogen I and II, I/II ratio and gastrin levels were 81.3 ± 46.6 ng/mL, 25.9 ± 17.1 ng/mL, 3.4 ± 1.3 and 131.9 ± 130.8 pg/mL, respectively, before treatment. At 1–3 months after eradication, serum pepsinogen I and II levels in the H. pylori-positive patients decreased to levels similar to those in the negative patients, whereas pepsinogen I/II ratio and gastrin levels remained lower and higher, respectively, than in the negative patients. Serum pepsinogen I/II ratio and gastrin levels then became similar between the groups at 12–15 months after eradication. In histological findings, inflammation and neutrophil activity decreased by 1–3 months, and atrophy in the corpus and metaplasia in the antrum decreased by 12–15 months.Conclusion : The results suggest that atrophic corpus gastritis and superficial gastritis are reversible, as indicated by both histological and serological findings in a long-term follow-up study.
    Materialart: Digitale Medien
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  • 3
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd.
    Journal of the European Academy of Dermatology and Venereology 18 (2004), S. 0 
    ISSN: 1468-3083
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Medizin
    Notizen: Background  We observed nishikinezumi, cinnamon-coloured (NC)/Fujita (F) mice aged between 5 and 28 weeks. These NC mice have skin eruptions that resemble human atopic dermatitis (AD) under conventional circumstances.Object  We investigated the skin of eruptive and non-eruptive lesions in NC/F mice by using haematoxylin–eosin (H&E) staining, toluidine blue staining and immunohistopathological study with immunoglobulin (Ig)EɛRI, CD23, interleukin (IL)-4, IL-5, interferon (INF)-γ and Ia antigen.Results  Histological examination of the eruptive lesions revealed the perivascular infiltration of many lymphocytes and mast cells into the upper dermis. Intracellular oedema of the epidermis, lymphocyte infiltration into the epidermis and liquefaction degeneration of the basal layer were also observed. The numbers of IL-4 and IL-5 positive cells in the eruptive lesions were larger than those of the non-eruptive lesions. IL-4 and IL-5 positive cells in the eruptive lesions increased weekly. Some IFN-γ positive cells were observed in the eruptive lesions after 21 weeks. IFN-γ positive cells were scarce in the skin of both the non-eruptive and eruptive lesions before 21 weeks. Serum IgE increased from 7 weeks to 21 weeks.Discussion  We confirmed that these findings indicated that T helper (Th)2-dominant immunological activation transformed to a Th1-dominant situation. Many IgEɛRI positive cells were recognized in the dermis of the eruptive lesions by the time IgE had decreased. We assumed that the dermatitis before 21 weeks was an IgE-mediated allergy. We have previously reported that older NC/F mice had positive patch-test reactions to mites. Because serum IgE decreased after 21 weeks, dermatitis after 21 weeks might be associated more with cell-mediated delayed hypersensitivity than with IgE-mediated immediate allergy.
    Materialart: Digitale Medien
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  • 4
    Digitale Medien
    Digitale Medien
    Chester : International Union of Crystallography (IUCr)
    Journal of synchrotron radiation 3 (1996), S. 225-230 
    ISSN: 1600-5775
    Quelle: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Thema: Geologie und Paläontologie , Physik
    Notizen: A synchrotron-radiation dynamic small-angle X-ray scattering (Synchrotron Radiation-DSAXS) system using an imaging plate has been developed at the Photon Factory, National Laboratory for High Energy Physics, Japan, in collaboration with the Department of Polymer Chemistry, Kyoto University, Japan, for studying the dynamic response of mesoscopic structures in polymers to applied mechanical stimuli. Small-angle X-ray scattering patterns of 100 × 100 mm2 have been successively recorded on a 400 × 200 mm2 stage-mounted imaging plate with a minimum time interval of 0.5 s. X-ray data are simultaneously obtained with stress and strain measurements on specimens subjected to a mechanical deformation. The performance of the DSAXS system is demonstrated along with some experimental results concerning the dynamic deformation of a b.c.c. lattice with paracrystalline distortion in a co-polymer having spherical microdomains under a large oscillatory shear deformation.
    Materialart: Digitale Medien
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  • 5
    ISSN: 1432-0428
    Schlagwort(e): Keywords Silent cerebral infarction ; adhesion molecules ; ICAM-1 ; VCAM-1 ; E-selectin ; carotid artery ; diabetes mellitus.
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Summary The purpose of this study was to investigate the relationship between complications arising from silent cerebral infarction (SCI) and changes in the levels of serum-soluble adhesion molecules in 82 elderly diabetic patients aged 60 years and older. SCI was found in 43 % of the 82 patients, with incidence increasing in relation to age. The prevalence of SCI was higher in subjects with hypertension, poor metabolic control and increased fibrinolysis. The levels of soluble intercellular adhesion molecule-1 (sICAM-1), vascular cell adhesion molecule-1 (sVCAM-1) and E-selectin (sE-selectin) were higher in diabetic patients than in non-diabetic subjects (p 〈 0.05, p 〈 0.001, and p 〈 0.05, respectively). Also, sICAM-1 and sVCAM-1 were found at increased levels in diabetic patients with SCI compared to those without SCI (p 〈 0.01 and p 〈 0.05, respectively). In particular, the level of sICAM-1 was increased in patients with SCI due to perforating arterial occlusion, while the level of sVCAM-1 was increased in patients with SCI due to cortical arterial occlusion. However, no significant difference was found in sE-selectin levels. Overall average of the intima and media thickness (IMT) of the common carotid arteries increased with age. IMT proved to be greater in patients with SCI than in patients without SCI (p 〈 0.05), and showed a weak but significant positive correlation with sVCAM-1, while no correlation was found with either sICAM-1 or sE-selectin levels. In conclusion, measurement of serum adhesion molecules may be useful for diagnosing the early stages of brain damage and for prophylactic treatment which may prevent the onset or progression of SCI. [Diabetologia (1998) 41: 911–917]
    Materialart: Digitale Medien
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  • 6
    ISSN: 1432-041X
    Schlagwort(e): Epithelial mesenchymal interaction ; Epithelial differentiation ; Digestive tract ; Lung mesenchyme ; Pepsinogen gene expression
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract We performed tissue recombination experiments to discover the mesenchymal influences on differentiation of epithelia in chicken digestive organs. Epithelia and mesenchymes were taken from the lung, esophagus, proventriculus, gizzard, small intestine and large intestine of 6-day chicken embryos and recombined in various associations and cultivated in vitro for 6 days. Rather unexpectedly, embryonic chicken pepsinogen (ECPg) gene, a marker of the proventricular epithelium, was induced in the gizzard epithelium, which does not express ECPg in normal development, by the proventricular and lung mesenchymes. In the second half of this study, we investigated the mode of action of mesenchymal cells on ECPg expression in gizzard epithelial cells more precisely using the cell aggregate culture system, in which gizzard epithelial cells were mixed with proventricular, gizzard or lung mesenchymal cells. We found that supporting action of lung mesenchymal cells on ECPg expression was even stronger than that of proventricular mesenchymal cells, and suggest that the action of lung mesenchyme may be due partly to the enhancement of epithelial cell proliferation. According to the results of this study, together with many facts obtained so far, we will discuss a new model for restricted expression of ECPg in the proventricular epithelium in normal development.
    Materialart: Digitale Medien
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  • 7
    Digitale Medien
    Digitale Medien
    Springer
    Abdominal imaging 22 (1997), S. 499 -501 
    ISSN: 1432-0509
    Schlagwort(e): Key words: Agenesis of inferior vena cava—Azygos–hemiazygos continuation—Budd–Chiari syndrome—Congestive liver cirrhosis—Retroaortic left renal vein.
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract. A 35-year-old woman with clinical features of Budd–Chiari syndrome is presented. Abdominal ultrasonography, computed tomography, and venography disclosed that the venous congestion in this patient resulted from complex venous anomalies including azygos–hemiazygos continuation, absent superior hepatic veins, and retroaortic transposition of the left renal vein.
    Materialart: Digitale Medien
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  • 8
    ISSN: 1432-2013
    Schlagwort(e): Key words Propionyl-L-carnitine ; Insulin ; Streptozotocin-induced diabetic rat ; Motor nerve conduction velocity ; Sciatic nerve blood flow ; Electroretinogram ; Sorbitol ; myo-Inositol
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract The effect of an analogue of L-carnitine, propionyl-L-carnitine, on the electroretinogram, motor nerve conduction velocity and nerve blood flow was determined in rats with streptozotocin-induced diabetes, and was compared with the effects of insulin alone or combined therapy. Oral administration of propionyl-L-carnitine (3 g/kg daily for 4 weeks) significantly increased caudal nerve motor conduction velocity and sciatic nerve blood flow in diabetic rats. There were no differences in the effects of insulin (8–10 U daily for 4 weeks), propionyl-L-carnitine and combined therapy. Although propionyl-L-carnitine significantly shortened the peak latency of the electroretinogram b-wave in diabetic rats, its effect was far weaker than that of insulin or combined therapy, with combined therapy producing the greatest improvement. These effects of propionyl-L-carnitine were accompanied by a decrease of serum lipid levels, an increase of the sciatic nerve carnitine content, and no changes of the tissue (nerve and retinal) sorbitol and myo-inositol concentrations. In contrast, insulin significantly reduced the tissue sorbitol content and markedly increased myo-inositol. These findings suggest that propionyl-L-carnitine may improve diabetic neuropathy and retinopathy without influencing the polyol pathway, and that this beneficial effect may be mediated through the amelioration of microcirculation and tissue carnitine content, thus probably increasing fatty acid oxidation.
    Materialart: Digitale Medien
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  • 9
    ISSN: 1432-2013
    Schlagwort(e): Propionyl-l-carnitine ; Insulin ; Streptozotocin-induced diabetic rat ; Motor nerve ; conduction velocity ; Sciatic nerve blood flow ; Electroretinogram ; Sorbitol ; myo-Inositol
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract The effect of an analogue ofl-carnitine, propionyl-l-carnitine, on the electroretinogram, motor nerve conduction velocity and nerve blood flow was determined in rats with streptozotocin-induced diabetes, and was compared with the effects of insulin alone or combined therapy. Oral administration of propionyl-l-carnitine (3 g/kg daily for 4 weeks) significantly increased caudal nerve motor conduction velocity and sciatic nerve blood flow in diabetic rats. There were no differences in the effects of insulin (8–10 U daily for 4 weeks), propionyl-l-carnitine and combined therapy. Although propionyl-l-carnitine significantly shortened the peak latency of the electroretinogram b-wave in diabetic rats, its effect was far weaker than that of insulin or combined therapy, with combined therapy producing the greatest improvement. These effects of propionyl-l-carnitine were accompanied by a decrease of serum lipid levels, an increase of the sciatic nerve carnitine content, and no changes of the tissue (nerve and retinal) sorbitol andmyo-inositol concentrations. In contrast, insulin significantly reduced the tissue sorbitol content and markedly increasedmyo-inositol. These findings suggest that propionyl-l-carnitine may improve diabetic neuropathy and retinopathy without influencing the polyol pathway, and that this beneficial effect may be mediated through the amelioration of microcirculation and tissue carnitine content, thus probably increasing fatty acid oxidation.
    Materialart: Digitale Medien
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