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Several ways to produce microporous and mesoporous carbon monoliths by template assisted synthesis routes are described. Pressed zeolite (HY) and silica powder tablets have been used as templates. Sucrose acts as a carbon precursor and as a binder between the carbon particles as well. In the case of zeolite template, the carbon porosity could be increased by additional loading of the template with ethene. Due to the balance between mechanic stability and porosity of the carbon monolith, an optimal amount of sucrose is required. The final products were characterized by low temperature nitrogen adsorption. 相似文献
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John Seifert Angela Frelich Linda Shecterle John St Cyr 《Journal of the International Society of Sports Nutrition》2008,5(1):1-5
D-ribose, a naturally occurring pentose carbohydrate, has been shown to replenish high- energy phosphates following myocardial ischemia and high intensity, repetitive exercise. Human studies have mainly involved short-term assessment, including potential toxicity. Reports describing adverse effects of D-ribose with prolonged ingestion have been lacking. Therefore, this study assessed the toxicity of extended consumption of D-ribose in healthy adults. Nineteen subjects ingested 20 grams/Day (10 grams, twice a Day) of ribose with serial measurements of biochemical and hematological parameters at Days 0, 7, and 14. No significant toxic changes over the 14-day assessment period occurred in complete blood count, albumin, alkaline phosphatase, gamma glutamyltransferase, alanine amiotransferase, and aspartate aminotransferase. However, D-ribose did produce an asymptomatic, mild hypoglycemia of short duration. Uric acid levels increased at Day 7, but decreased to baseline values by Day 14. D-ribose consumption for 14 days appears not to produce significant toxic changes in both hematological and biochemical parameters in healthy human volunteers. 相似文献
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PM Roger V Mondain MC St Paul F Peyrade A Pesce JG Fuzibet JF Michiels P Dellamonica 《Canadian Metallurgical Quarterly》1998,27(32):1617-1620
OBJECTIVE: There is substantial evidence demonstrating the aggravating effect of human immunodeficiency virus (HIV) infection on the progression of chronic hepatitis C virus (HCV) infection. There is however, little data on the affect of certain factors which could affect liver pathology findings in patients with concomitant HIV infection such as the duration of HIV infection or T-cell subpopulation counts. We examined pathology findings in patients with concomitant HIV and HCV infections to determine the impact of immunodepression. PATIENTS AND METHODS: We reviewed liver pathology data collected in patients with concomitant HIV and HCV infections grouping patients according to severity of the liver pathology: group 1 = cirrhosis or active hepatitis; group 2 = minimally active hepatitis or histologically normal liver. Transparietal liver biopsies were obtained for the work-up of viral hepatitis or because of long-term unexplained fever or suspected lymphoma. Epidemiological and biological data were obtained from medical files. The duration of the liver disease was estimated from the date of exposure to risk of immunodepression as determined by the peripheral CD4+ and CD8+ counts. All pathology specimens were read by two pathologists who established the Knodell score for each patient. RESULTS: Fifty patients were included: 23 were classed in group 1 and 28 in group 2. The Knodell score was significantly different between the two groups, 11 +/- 4 and 4 +/- 3 respectively (p < 0.0001). Disease duration was similar for the two groups: mean 8 years. Mean CD4+ count was significantly higher in group 1: 312/mm3 versus 110/mm3 for group 2 (p = 0.0057); as was the mean CD8+ count (758/mm3 versus 360/mm3, p = 0.0013). For the entire study population, there was a significantly negative correlation (p < 0.05) between the Knodell score and the CD4+ count (r = 0.31) and for the CD8+ count (r = 0.41). CONCLUSION: HCV-related liver pathology in patients co-infected with HIV depends on the level of immunodepression. CD8+ counts are better correlated with pathology findings than with CD4+ counts. 相似文献
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H Reznik-Wolf TA Treves M Davidson J Aharon-Peretz PH St George Hyslop J Chapman AD Korczyn B Goldman E Friedman 《Canadian Metallurgical Quarterly》1996,98(6):700-702
Germline mutations in the presenilin 1 (PS1) gene apparently account for the majority of early-onset, familial Alzheimer's disease (AD). Using a mutation-screening strategy (denaturing gradient gel electrophoresis; DGGE), we analyzed a large family with early onset AD and seizures. The patients in this family showed a novel missense mutation in exon 5 of the PS1 gene (A to T change in codon 120, altering glutamine to aspartic acid). This novel mutation is located within the second hydrophilic domain of the molecule, a region not particularly involved in previously described germline mutations, and is of unknown biological significance. These results also demonstrate that DGGE can be used effectively to screen for mutations within this gene. 相似文献
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Heiko Klarl 《Informatik-Spektrum》2007,30(3):175-177
Ohne Zusammenfassung 相似文献
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The invasive potential of eight established human tumour cell lines of different origin has been studied in the Matrigel assay. Between 25% and 70% of the cells migrated through the Matrigel layer within 24 h, indicating that invasiveness varies with the cell type. Semiquantitative measurements of the proteases MMP-2 and MMP-9, and cathepsins B and L were performed in these cell lines and the cell culture media. High invasive potential was found in those cell lines expressing high levels of cathepsins B and L or matrix metal proteases (MMP), either alone or in combination. Overexpression of one of these enzymes is enough to explain a high invasive potential of a cell line. Selective protease inhibitors at 10 nM concentration in the culture medium were used to inhibit the migration of tumour cells in the Matrigel assay. The MMP inhibitor Batimastat reduced the invasive potential of all cell lines studied independently of the MMP expression. The effect of cysteine protease inhibitors was strongly correlated with the protease profile of the tumour cell line. Our findings support the hypothesis of a very complex activation cascade of matrix-degrading proteolytic enzymes and they underline the need to analyse the protease profile of any tumour before beginning an antiproteolytic tumour treatment. 相似文献