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  • 1995-1999  (6)
  • 1935-1939
  • spirooxazine  (4)
  • Phenylalanine  (2)
  • 1
    ISSN: 1432-1076
    Schlagwort(e): Key words Phenylketonuria ; Phenylalanine ; Magnetic resonance ; imaging ; Evoked potentials ; Myelination
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract White matter abnormalities on MRI have been observed in phenylketonuria (PKU) patients with late onset neurological symptoms as well as in neurologically inconspicious patients. We investigated 14 early treated adolescents at an age between 12 and 17 years (mean age 14.3 years) with classical PKU as well as one retarded patient with atypical PKU by cranial MRI with spinecho T1-, T2- and proton density sequences. Clinical examination was normal. Visual evoked potential (VEP) examination showed a prolonged latency of peak P100 (mean 122.6 ms; control mean 115.9) and IQ testing showed a mean IQ of 101.1. To investigate the influence of plasma phenylalanine (Phe) levels three approaches were used: Phe was determined for the day of MRI, for a period of 6 months prior to MRI and for lifetime up to 12 years. MRI scans revealed areas of abnormally increased signal intensity on T2-weighted and proton density images in 12 (86%) patients, preferably involving the parieto-occipital lobes. MRI of the patient with atypical PKU was normal. MRI findings correlated most strongly to long-term dietary control up to 12 years. We found no correlation with the other parameters of biochemical control, IQ or VEP latency. The nature and prognosis of MRI abnormalities in neurologically normal PKU patients remain unclear although abnormalities in VEPs which were not associated with the degree of MRI abnormalities in our sample indicate a disturbance in myelination along the visual pathways.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 2
    Digitale Medien
    Digitale Medien
    Springer
    European journal of pediatrics 155 (1996), S. S97 
    ISSN: 1432-1076
    Schlagwort(e): Key words Phenylketonuria ; Intelligence ; Education ; Professional career ; Phenylalanine ; control
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract The intellectual status and professional careers of 51 young adults with phenylketonuria whose treatment started before 3 months of age are described. Their mean IQ was 97 (SD = 16). Of the IQs, 4% were more than 2 SD below the norm. The distribution of types of schooling of the patients was comparable to that in the German population. The professional careers of nearly all the patients were according to their educational level. Within the sample the outcome was significantly correlated with phenylalanine (Phe) control, even when the patients’ social background was statistically taken into account. The main influence of Phe on intelligence seems to occur during the first decade of life since IQ data remain stable even after Phe levels increased during adolescence.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 3
    ISSN: 1573-4846
    Schlagwort(e): photochromism ; photochromic coatings ; spirooxazine ; photochromic properties ; mechanical properties
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie
    Notizen: Abstract The experimental results on the photochromic and mechanical properties of coatings containing 1,3-dihydro-1,3,3-trimethylspiro[2H-indole-2,3′-(3H)-naphth(2,1-b)(1,4) oxazine] (SO) derived from 3-glycidyloxypropyltrimethoxysilane (GPTMS), bisphenol A (BPA) and 1-methylimidazole (MI) by sol-gel processing are presented. It is shown that heat treatment temperature is a conflicting factor to the photochromic intensity (Δ A 0), photostability and abrasion resistance of the photochromic coatings. With increasing densification temperature the matrix rigidity increases leading to a decrease of Δ A 0 and at the same time an enhancement of both abrasion resistance and photostability, the optimum heat treatment temperature is 110°C under our experimental conditions. By the use of certain additives, e.g., fluorosilanes (FAS), not only Δ A 0 but also the photostability and the abrasion resistance of the photochromic coatings have been further improved.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 4
    Digitale Medien
    Digitale Medien
    Springer
    Journal of sol gel science and technology 8 (1997), S. 927-929 
    ISSN: 1573-4846
    Schlagwort(e): organic-inorganic hybrids ; sol-gel ; photochromic performance ; spirooxazine
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie
    Notizen: Abstract Organic-inorganic hybrid materials synthesized via sol-gel processing are excellent solid matrices for photochromic dyes like spirooxazine, and the photochromic performance can be further enhanced by introducing suitable additives. This work describes the effects of additives on the photochromic intensity (Δ A 0), decolouration rate (k) and photostability of spirooxazine in sol-gel derived organic-inorganic hybrid matrices. They include fluoro-alkylsilane (FAS), bisphenol A (BPA) and methyl-imidazole (MI). FAS enhances both Δ A 0 and photostability, but has little effect on k. The higher the content of BPA, the higher the Δ A 0 and the higher the photostability, but the lower the k. The effect of MI on Δ A 0 and k is not so considerable as that of BPA and is a little complicated, while significant improvement in photostability is achieved by the addition of MI at an optimum concentration with the presence of BPA at a higher content.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 5
    ISSN: 1573-4846
    Schlagwort(e): photochromism ; photochromic coatings ; spirooxazine ; photochromic properties ; mechanical properties
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie
    Notizen: Abstract The experimental results on the photochromic and mechanical properties of coatings containing 1,3-dihydro-1,3,3-trimethylspiro[2H-indole-2,3′-(3H)-naphth(2,1-b)(1,4) oxazine] (SO) derived from 3-glycidyl-oxypropyltrimethoxysilane (GPTMS), bisphenolA (BPA) and 1-methylimidazole (MI) by sol-gel processing are presented. It is shown that heat treatment temperature is a conflicting factor to the photochromic intensity (ΔA 0), photostability and abrasion resistance of the photochromic coatings. With increasing densification temperature the matrix rigidity increases leading to a decrease of ΔA 0 and at the same time an enhancement of both abrasion resistance and photostability, the optimum heat treatment temperature is 110°C under our experimental conditions. By the use of certain additives, e.g., fluorosilanes (FAS), not only ΔA 0 but also the photostability and the abrasion resistance of the photochromic coatings have been further improved.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 6
    Digitale Medien
    Digitale Medien
    Springer
    Journal of sol gel science and technology 8 (1997), S. 927-929 
    ISSN: 1573-4846
    Schlagwort(e): organic-inorganic hybrids ; sol-gel ; photochromic performance ; spirooxazine
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie
    Notizen: Abstract Organic-inorganic hybrid materials synthesized via sol-gel processing are excellent solid matrices for photochromic dyes like spirooxazine, and the photochromic performance can be further enhanced by introducing suitable additives. This work describes the effects of additives on the photochromic intensity (ΔA 0), decolouration rate (k) and photostability of spirooxazine in sol-gel derived organic-inorganic hybrid matrices. They include fluoroalkylsilane (FAS), bisphenolA (BPA) and methyl-imidazole (MI). FAS enhances both ΔA 0 and photostability, but has little effect onk. The higher the content of BPA, the higher the ΔA 0 and the higher the photostability, but the lower thek. The effect of MI on ΔA 0 andk is not so considerable as that of BPA and is a little complicated, while significant improvement in photostability is achieved by the addition of MI at an optimum concentration with the presence of BPA at a higher content.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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