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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.
AR Jones BSC AJP Sandison FRCS WJ Owen MS FRCS 《International journal of clinical practice》1997,51(5):294-295
Pre-clerking of all patients undergoing elective general surgical operations was introduced at our hospital in an attempt to reduce an unacceptably high operation cancellation rate. A prospective audit has been performed on the effect of this policy on the cancellation rate. Before the introduction of pre-clerking there was a marked seasonal variation in the number of patients who failed to attend for surgery, which could be explained by absence on holiday. This seasonal variation disappeared after the start of pre-clerking clinics, but there has been no reduction in the number of cancellations for medical reasons. 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.
Berbaum KS; el-Khoury GY; Franken EA Jr; Kathol M; Montgomery WJ; Hesson W 《Radiology》1988,168(2):507-511
The effect of knowledge of localizing symptoms and signs in the detection of fractures was studied. Forty radiographs of the extremities were examined twice by seven radiologists; the sessions were separated by 4 months. In 26 cases, a subtle fracture was present; 14 cases were normal. In half of the cases at each session, the precise location of pain, tenderness, or swelling was provided. The observer was asked to determine if the case was normal or abnormal (provide the exact location of the fracture) and to indicate the degree of confidence in the diagnosis. Responses were converted to a numeric scale for analysis. Analysis of receiver operator characteristic parameters indicates that clues regarding location of trauma facilitate detection of fractures. The improvement is based largely on an increased true-positive rate without an increased false-positive rate, regardless of the decision criteria of the radiologist (overall willingness to "overread" or "underread"). This has direct clinical applicability and reinforces the plea of radiologists for precise clinical information. 相似文献
7.
Lei Wan, Poliporus mylittae Cook et Mass(Omphalia lapidescena Scbraet) is a kind of fungus used in traditional Chinese medicine, as an antheiminthie From Lei Wan, an "active component designated as. S-4001 had been isolated.Preliminary results indicate that S-4001 belongs to D, β, 1-3 glucan with some 1-6 linkages.After administration of S-4001, significant antiinflammatory activity was found in various experimental animal models, including croton oil induced ear edema in mice and agar or yeast induced ankle swelling in rats. An inhibitory action on leucocyte migration inducced by intraperitoneal injection of CMC in rats was also observed. The plasma content of corticosterone was significantly increased, but the content of ascorbic acid in the adrenals did not change in rats given S-4001. Apart from these actions, S-4001 showed a number of immunostimulating actions such as increasing the clearance of Congo red from mice blood and potentiating the immunohemolysis reaction in 615 mice. 相似文献
8.
Background
There is currently an unprecedented expressed need and demand for estimates of maternal mortality in developing countries. This has been stimulated in part by the creation of a Millennium Development Goal that will be judged partly on the basis of reductions in maternal mortality by 2015. 相似文献9.
10.
Lactate production in isolated perfused rat lung 总被引:1,自引:0,他引:1