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排序方式: 共有498条查询结果,搜索用时 15 毫秒
1.
Fruit and vegetable intake is associated with lower risk of chronic diseases as a result of consumption of antioxidant substances. Organic foods are thought to have higher antioxidant capacity, because this form of agricultural management could induce synthesis of secondary compounds such as polyphenols. The objective of this work is to evaluate polyphenol content and antioxidant capacity in organically (OG) and conventionally (CV) grown fruits and vegetables, as well as in different parts of the plants. Soluble and hydrolysable polyphenols were quantified by Folin–Ciocalteu reagent, and the antioxidant capacity was measured by the DPPH radical method. The results showed that organic fruits tend to have higher hydrolysable polyphenol contents than conventional ones, with values being 11.5% in orange peels, to 72.6% in papaya peels, higher for hydrolysable polyphenols. Fruit peels also showed higher concentration of polyphenols than pulp, reaching, for bananas and tangerines, twice the amount found in pulps, which reflected in higher antioxidant capacity. Polyphenol content and antioxidant capacity varied among organic and conventional vegetables with no prevalence from either agricultural type. This study suggests that the effect of organic practices results in different effect patterns according to the plant species analysed, with fruits being more susceptible to the induction of polyphenol synthesis, and the greatest accumulation of polyphenols in external plant tissues. In general, organic agriculture results in food products with similar or slightly higher polyphenol content and antioxidant capacity. 相似文献
2.
Butyrate infusions in the ovine fetus delay the biologic clock for globin gene switching. 总被引:4,自引:0,他引:4 下载免费PDF全文
S P Perrine A Rudolph D V Faller C Roman R A Cohen S J Chen Y W Kan 《Proceedings of the National Academy of Sciences of the United States of America》1988,85(22):8540-8542
The switch from fetal to adult hemoglobin expression is regulated in many mammalian species by a developmental clock-like mechanism and determined by the gestational age of the fetus. Prolonging fetal globin gene expression is of considerable interest for therapeutic potential in diseases caused by abnormal beta-globin genes. Butyric acid, which is found in increased plasma concentrations in infants of diabetic mothers who have delayed globin gene switching, was infused into catheterized fetal lambs in utero during the time of the normal globin gene switch period. The globin gene switch was significantly delayed in three of four butyrate-treated fetuses compared with controls and was entirely prevented in one fetus in whom the infusion was begun before the globin switch was under way. These data provide a model for investigating and arresting the biologic clock of hemoglobin switching. 相似文献
3.
The morbidity and mortality of major abdominal surgical interventions in 34 histologically proven cirrhotic patients are analysed by the authors. The surgical interventions were carried out by urgent, absolute and elective indications. 37 general and surgical complications could have been observed following the major abdominal surgery of 34 cirrhotics. 7 out of 34 patients died. Suture-line insufficiency, peritonitis, sepsis and other inflammatory processes turned out most frequently among the complications. The Child criteria, the prothrombin level and white blood cell count proved to be useful prognostic factors by statistical analysis. 相似文献
4.
The intraoperative measurement of the afferent circulation of the liver, namely the hepatic artery flow and portal venous flow was carried out upon 14 anaesthetized patients having carcinoma of the splanchnic area, mainly in the head of the pancreas, by means of transit time ultrasonic volume flowmeter. The hepatic artery flow, portal venous flow and total hepatic flow were 0.377 +/- 0.10; 0.614 +/- 0.21; 0.992 +/- 0.276 l/min, respectively. The ratio of hepatic arterial flow to portal venous flow was 0.66 +/- 0.259. There was a sharp, significant increase in hepatic arterial flow (29.8 +/- 6.1%, p < 0.01) after the temporary occlusion of portal vein, while the temporary occlusion of hepatic artery did not have any significant effect on portal venous circulation. The interaction between hepatic arterial flow and portal venous flow is a much disputed question, but according to the presented data here, it is unquestionable, that the decrease of portal venous flow immediately results a significant increase in hepatic artery circulation. 相似文献
5.
Michael S. Boosalis Tohru Ikuta Betty S. Pace Silvana da Fonseca Gary L. White Douglas V. Faller Susan P. Perrine 《Blood cells, molecules & diseases》1997,23(3):434-442
ABSTRACT: Short-chain fatty acids, such as butyrate and propionate, induce fetal globin gene expression and are under clinical investigation in the β-hemoglobinopathies. Limitations of the short-chain fatty acids as therapeutics include their rapid metabolism and a tendency to induce cell growth arrest if administered for prolonged periods. In studies described here, the cellular effects of other inducers of fetal globin, phenoxyacetic acid and derivatives of short-chain fatty acids and cinnamic acids, were investigated in the human erythroid cell line K562, the IL-3 dependent multi-lineage cell line (32D), and in mice and primates. Several test compounds supported 32D cell proliferation despite a 50-fold depletion of IL-3, which resulted in growth arrest and apoptotic death in control cells. The degree of proliferation induced by certain test compounds was similar to the degree of proliferation induced by Erythropoietin and G-CSF in the cells. Eight of ten compounds induced γ globin mRNA in K562 cells. A 2.5 to 6-fold increase in reticulocytosis was observedin vivoin mice treated with two prototype compounds. Pharmacokinetic studies of three prototype compounds demonstrated millimolar plasma concentrations after single oral doses for many hours in primates. These findings identify orally bioavailable compounds which induce γ globin gene expression and hematopoietic cell proliferation through an activity which partially abrogates requirements for IL-3. Such compounds provide potential for oral therapeutics which stimulate proliferation of hematopoietic cells of multiple lineages, as well as inducing fetal globin. 相似文献
6.
7.
Previous studies have implied the existence of a trans-dominant intracellular repressor able to down-regulate the expression of the entire family of class I MHC genes in the genome of the K562 erythroleukemia cell line. This study demonstrates, however, that the transfection of human or murine class I genes into K562 cells leads to the cell surface expression of the transfected MHC gene product in all situations, even when several kilobases of 5' flanking sequence were included in the transfected genes. The endogenous cellular class I MHC genes remained repressed in the transfected cells. These findings suggest that repression of class I MHC gene expression in K562 may not be mediated predominantly by a trans-dominant repressor of MHC gene expression; rather, other more complex regulatory influences might exist. 相似文献
8.
Faller G Berndt R Borchard F Ell C Fuchs KH Geddert H Gossner L Günther T Kirchner T Koch HK Langner C Lüttges J May A Müller S Oberhuber G Seitz G Stolte M Tannapfel A Vieth M Walch A Rüschoff J;Working Group for Gastroenterological Pathology German Society for Pathology 《Der Pathologe》2003,24(1):9-14
There are a number of difficulties regarding the diagnosis of Barrett's mucosa and the varying grades of neoplasia that may be associated with it. It was therefore the aim of a consensus conference of the "Working Group for Gastroenterological Pathology within the German Society of Pathology" to achieve standardization regarding the following issues: definition and diagnostic criteria for Barrett's mucosa and its discrimination from intestinal metaplasia of the cardia, diagnostic criteria for intraepithelial neoplasia, number of biopsies necessary to establish the diagnosis, significance of additional immunohistochemical and/or molecular biological methods as well as importance of a second opinion in the diagnosis of intraepithelial neoplasia. 相似文献
9.
M. Laforet N. Froelich A. Parissiadis B. Pfeiffer A. Schell B. Faller M.-L. Woehl-Jaegle J.-P. Cazenave M.-M. Tongio 《Tissue antigens》1997,50(4):347-350
HLA class I typing performed in parallel by molecular biology and serology has revealed cases where an HLA class I allele was identified whereas the corresponding antigen was not detected on the cell surface. In the present report, we describe four members of a family in whom an HLA-A 1 allele identified at the molecular level was typed as A "blank" by lymphocytotoxicity. This serologically blank antigen was undetectable by isoelectric focusing (IEF). Sequencing of the HLA-A*01 allele from the promoter region to the eighth exonic region revealed insertion of a "C" nucleotide at the beginning of the fourth exon as compared to the common HLA-A*0101 allele. This mutation causes a frame shift, giving rise to an early stop codon in the fourth exon. 相似文献
10.
Odenbreit S Faller G Haas R 《International journal of medical microbiology : IJMM》2002,292(3-4):247-256
The attachment of the bacterial pathogen Helicobacter pylori (H. pylori) to gastric epithelial cells is commonly believed to be required for an efficient and persistent colonization of the human stomach as well as for host cell trans-membrane signaling. In the past, several putative adhesins were postulated, including the outer membrane proteins AlpAB and the bacterial lipopolysaccharide (LPS) presenting oligomeric Lewis x (Le(x)) sugar components. We investigated the AlpAB-mediated and the Le(x)-dependent binding by knockout mutagenesis in one distinct strain, H. pylori P1. We show here that the mutagenesis of either alpA and/or alpB dramatically reduced the adherence of H. pylori P1 to a given gastric biopsy section. None of these mutations influenced the surface exposure of the Le(x) antigen, suggesting that the assembly and/or presentation of LPS is independent of the AlpAB outer membrane proteins. However, a truncation of the LPS O-side chain by a galE mutation abolished the presentation of the Le(x) epitope. This Le(x)-negative strain did not show any significant reduction in its binding capacity to the gastric tissue, when compared with the corresponding wild-type strain. From these data we conclude that the AlpAB-specific adherence is independent of the composition of the LPS and that the oligomeric Le(x) structure does not confer binding to the gastric biopsy material used in this study. As the adhesion properties of our H. pylori strain P1 vary in dependence on the respective biopsy donor it is assumed that the surface-exposed Le(x) epitope recognizes a different host cell receptor than AlpAB, which was probably not present in the tissue sections used in this study. 相似文献