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81.
82.
BACKGROUND: In this study we investigated the cellular absorption rates, antioxidant and free radical scavenging activity of vitamin C-lipid metabolites. The absorption was measured in a human lymphoblastic cell line using a spectrophotometric technique. MATERIAL/METHODS: Cellular vitamin C levels in the human lymphoblastic H9 cell line were measured using the 2,4-dinitrophenylhydrazine spectrophotometric technique. Free radical scavenging activity of vitamin C-lipid metabolites was measured by the reduction of 1,1-diphenyl-2-picryl hydrazyl (DPPH) to 1,1-diphenyl-2-picryl hydrazine. Vitamin C-lipid metabolite scavenging of peroxyl radical oxygen reactive species (ORAC) was determined by fluorescence spectrophotometry. RESULTS: Compared to ascorbic acid (AA), calcium ascorbate (CaA), and calcium ascorbate-calcium threonate-dehydroascorbate (Ester-C), vitamin C-lipid metabolites (PureWay-C) were more rapidly absorbed by the H9 human T-lymphocytes. The vitamin C-lipid metabolites (PureWay-C) also reduced pesticide-induced T-lymphocyte aggregation by 84%, while calcium ascorbate-calcium threonate-dehydroascorbate (Ester-C) reduced aggregation by only 34%. The vitamin C-lipid metabolites (PureWay-C) demonstrated free radical scavenging activity of nearly 100% reduction of DPPH at 20 microg/ml and oxygen radical scavenging of over 1200 micro Trolox equivalents per gram. CONCLUSIONS: These data demonstrate that the vitamin C-lipid metabolites (PureWay-C) are more rapidly taken-up and absorbed by cells than other forms of vitamin C, including Ester-C. This increased rate of absorption correlates with an increased protection of the T-lymphocytes from pesticide toxicities. Further, vitamin C-lipid metabolites (PureWay-C) are a potent antioxidant and have significant free radical scavenging capabilities. 相似文献
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84.
F Arreola R Paniagua J Herrera S Díaz-Bensussen L Mondragón J A Bermúdez E Pérez Pastén S Villalpando 《Archives of andrology》1986,16(2):151-154
Plasma zinc and pituitary and testicular hormone concentrations were measured in two groups of male adolescents. One group comprised insulin-dependent diabetes mellitus patients, aged 14-19 years; the other, as control, included 12 healthy youngsters aged 13-19 years. Plasma concentration of zinc, prolactin, testosterone, and dihydrotestosterone were lower in diabetics than in controls, whereas the ratios of androstenedione and androstenedione to testosterone + dihydrotestosterone were higher. Plasma FSH and LH were normal. These results suggest a diminished conversion of androstenedione to testosterone and relate zinc with the 17-beta-hydroxysteroid dehydrogenase enzyme activity. 相似文献
85.
Keratoendotheliitis fugax hereditaria. A clinical and specular microscopic study of a family with dominant inflammatory corneal disease 总被引:2,自引:0,他引:2
A peculiar hereditary corneal disease seen in one pedigree is presented. The disease manifests itself as transient attacks of kerato-endotheliitis. These attacks last from a few days to some weeks. Clinically, corneal oedema and endothelial guttata-like changes with very slight anterior chamber reaction can be seen; after many attacks there may be permanent opacities in the stroma. Endothelial specular photography during an attack reveals dramatic changes: large black nonreflecting areas between quite normal-looking hexagonal cells. Also between the attacks and among family members who have no clinical corneal disease, changes in the endothelium: black spots in the centres of endothelial cells and marked pleomorphism, are to be seen. Among the family members a high incidence of collagen diseases was found. 相似文献
86.
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88.
Sandrine Péroche Ghania Degobert Jean-Luc Putaux Marie-Geneviève Blanchin Hatem Fessi Hélène Parrot-Lopez 《European journal of pharmaceutics and biopharmaceutics》2005,60(1):123-131
This work describes the synthesis of new amphiphilic perfluorohexyl- and perfluorooctyl-propanethio-beta-cyclodextrins and the comparison of the ability of these molecules and alkyl analogue, nonanethio-beta-cyclodextrin to form nanospheres. Nanospheres were prepared using nanoprecipitation method (perfluoroalkylthio-beta-cyclodextrin in THF [0.11 x 10(-3)M], stirring rate 700rpm, addition of aqueous phase at 64 degrees C into organic phase at 50 degrees C). They were characterised by Photon Correlation Spectroscopy (PCS) and by electron microscopy (SEM and cryo-TEM). The nanospheres prepared from these new beta-cyclodextrin derivatives have an average size of 260nm, and appear to be spherical in cryo-TEM images. Whereas alkyl analogue forms polydisperse aggregates with sizes in the range 60-350nm. 相似文献
89.
Misuse of zopiclone and convulsions during withdrawal. 总被引:3,自引:0,他引:3
It has been documented that benzodiazepines have the potential to cause dependence and withdrawal reactions, including convulsions. However, the available data concerning zopiclone, a nonbenzodiazepine hypnotic, are insufficient. The present study describes the case of a 36-year-old man who repeatedly misused zopiclone, in daily doses of 60-90 mg. Furthermore, the patient suffered from convulsion on two occasions following abrupt withdrawal of zopiclone. The concomitant use of alcohol, trimipramine, and promazine may have contributed to the development of convulsions. It is concluded that zopiclone may cause problems associated with misuse and withdrawal reactions similar to those of benzodiazepines. 相似文献
90.
S. Túri M. Visy Á. Vissy V. Jászai Zs. Czirbesz I. Haszon Zs. Szelid I. Ferkis 《Pediatric nephrology (Berlin, Germany)》1989,3(3):235-239
A retrospective multicentre study of 341 children with persistent/recurrent, isolated haematuria is described. The haematuria was isolated for at least 6 months at the beginning of observation. The duration of follow-up was 2–5 years in 201, 5–10 years in 119, 10–15 years in 19, and over 15 years in 2 cases. Of these patients 47.8% became symptom-free. In 18.4% the haematuria remained isolated; in 13.8% it was combined with proteinuria over 250 mg/day more than 2 years later. The occurrence of associated proteinuria increased progressively with time. It was 8.6% between the 3rd and 5th years, and 37.0% after the 5th year. Renal biopsy was performed because of the symptoms of glomerular disease in 47 cases at an average time of 12 months following the appearance of proteinuria. Proteinuria appeared after a 2–5, 5–10, 10–15 and more than 15 years follow-up period in 16, 23, 6, and 2 patients respectively; 14 of them had Alport's nephropathy. The percentage of more serious azotaemia was 1.7 (creatinine clearance: 10–50 ml/min per 1.73 m2) and 0.3 (creatinine clearance: < 10 ml/min per 1.73 m2). Mortality was 0.58%. Most of the patients who developed severe azotaemia had persistent microscopic haematuria at the beginning. The prevalence of hypertension was only 1.2%. The time of its appearance was above 5 years in 2 and below 5 years in 2 cases. All these patients had chronic glomerulonephritis. The haematuria was associated with hypercalciuria in 19.9%. In 14.3% of the overall group of patients urolithiasis developed 2–15 years after onset. All of these had hypercalciuria. Our findings suggest that symptoms of isolated haematuria may last for a longterm period and need systematic control. When proteinuria and/or hypertension is associated with haematuria a worse prognosis can be expected.Participating paediatric hospitals and university departments: Second Department of Paediatrics, I. Semmelweis Medical University of Budapest (M. Visy); Department of Paediatrics, University Medical School of Pécs (V. Jászai); Department of Paediatrics, A. Szent-Györgyi Medical University of Szeged (I. Haszon, S. Túri); County Children's Hospital, Miskolc (Á. Vissy); P. Heim Children's Hospital, Budapest (Z. Czirbesz); County Children's Hospital, Györ (Zs. Szelid); Buda-Children's Hospital, Budapest (I. Ferkis); I. Apáthy Hospital, Budapest (J. Kisbán); János Hospital, Budapest (I. Marosváry); Hospital of Hungarian State Railway, Budapest (J. Fehér); L. Madarász Hospital, Budapest (F. Kalmár); South Pest Hospital, Budapest (G. Halász); County Children's Hospital, Pécs (E. Kolman); County Children's Hospital, Gyula (P. Sipos); County Children's Hospital, Szolnok (I. Jaksics); County Children's Hospital, Debrecen (Á. Miskolczi); County Children's Hospital, Tatabánya (I. Kiss); County Children's Hospital, Eger (M. Frank, E. Ladányi); County Children's Hospital, Nyíregyháza (E. Bujdosó); County Children's Hospital, Szombathely (M. Andics); Kerepestarcsa Hospital, Budapest (M. Marcell); Komárom Hospital, Komárom (J. Kecskés) 相似文献