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11.
Roslyn B. Alfin-Slater Lilla Aftergood H. Joseph Hernandez Elizabeth Stern Daniel Melnick 《Journal of the American Oil Chemists' Society》1969,46(9):493-497
The effect of feeding aflatoxin, as a natural food contaminant, to rats over long periods of time was studied using multigeneration
and longevity tests. The test animals in the multigeneration study consisted of three groups of rats fed diets containing
0, 1 and 10 ppb of aflatoxin (predominantly B1) continued over four generations, with animals of the first and fourth generation fed the diets for 104 weeks. These diets
were in proper nutritional balance and included 35% ground roasted peanut products; the ration with 0 ppb aflatoxin excluded
the peanuts usually discarded; the one with 1 ppb had the roasted discards returned, while the ration with 10 ppb included
the discards in amount 10 times that which had been initially removed. Another longevity study was also performed in which
rats were fed diets containing aflatoxin at a level of 80 ppb. In this case, the test peanuts, also fed as a simulated peanut
butter at 35% concentration, consisted entirely of roasted peanut discards. Control diets provided no peanut components. Animals
fed the low levels of aflatoxin grew as well and actually had a higher percentage survival at 104 weeks than did the animals
on the control, aflatoxinfree diets. Organ weights, liver total lipid and cholesterol levels were comparable in all groups.
Pathological abnormalities, e.g., hemorrhagic and opaque spots and mottling in some of the livers, were attributed to the
aging process since the abnormalities appeared in the control as well as the experimental groups. In the animals fed the aflatoxin
at 80 ppb, which has been reported by several investigators to produce well-defined hepatomas in rats, there was liver involvement
and some biochemical changes occurred that were not noted in the controls. However, no hepatomas were observed in these animals
even after 21 months on this diet. The liver lesions, indicative of a toxic effect, have not been associated with the development
of hepatomas. It is possible that some components of the diet used in these experiments may have protected the animal against
hepatoma formation. Our studies indicate that there may be a tolerance for aflatoxin as judged by results in one species of
rats when whole ground roasted peanuts provide the natural contaminant.
Presented in part at the AOCS Meeting, New York, October 1968. 相似文献
12.
Feature subset selection for improving the performance of false positive reduction in lung nodule CAD. 总被引:2,自引:0,他引:2
Lilla B?r?czky Luyin Zhao K P Lee 《IEEE transactions on information technology in biomedicine》2006,10(3):504-511
We propose a feature subset selection method based on genetic algorithms to improve the performance of false positive reduction in lung nodule computer-aided detection (CAD). It is coupled with a classifier based on support vector machines. The proposed approach determines automatically the optimal size of the feature set, and chooses the most relevant features from a feature pool. Its performance was tested using a lung nodule database (52 true nodules and 443 false ones) acquired by multislice CT scans. From 23 features calculated for each detected structure, the suggested method determined ten to be the optimal feature subset size, and selected the most relevant ten features. A support vector machine classifier trained with the optimal feature subset resulted in 100% sensitivity and 56.4% specificity using an independent validation set. Experiments show significant improvement achieved by a system incorporating the proposed method over a system without it. This approach can be also applied to other machine learning problems; e.g. computer-aided diagnosis of lung nodules. 相似文献
13.
Beta Bdi Patrick M. Pilz Lilla Mrtha Miriam Lang Ouafa Hamza Mikls Fagyas Petra L. Szab Dietmar Abraham Attila Tth Bruno K. Podesser Attila Kiss Zoltn Papp 《International journal of molecular sciences》2021,22(20)
Post-ischemic left ventricular (LV) remodeling and its hypothetical prevention by repeated remote ischemic conditioning (rRIC) in male Sprague–Dawley rats were studied. Myocardial infarction (MI) was evoked by permanent ligation of the left anterior descending coronary artery (LAD), and myocardial characteristics were tested in the infarcted anterior and non-infarcted inferior LV regions four and/or six weeks later. rRIC was induced by three cycles of five-minute-long unilateral hind limb ischemia and five minutes of reperfusion on a daily basis for a period of two weeks starting four weeks after LAD occlusion. Sham operated animals served as controls. Echocardiographic examinations and invasive hemodynamic measurements revealed distinct changes in LV systolic function between four and six weeks after MI induction in the absence of rRIC (i.e., LV ejection fraction (LVEF) decreased from 52.8 ± 2.1% to 50 ± 1.6%, mean ± SEM, p < 0.05) and in the presence of rRIC (i.e., LVEF increased from 48.2 ± 4.8% to 55.2 ± 4.1%, p < 0.05). Angiotensin-converting enzyme (ACE) activity was about five times higher in the anterior LV wall at six weeks than that in sham animals. Angiotensin-converting enzyme 2 (ACE2) activity roughly doubled in post-ischemic LVs. These increases in ACE and ACE2 activities were effectively mitigated by rRIC. Ca2+-sensitivities of force production (pCa50) of LV permeabilized cardiomyocytes were increased at six weeks after MI induction together with hypophosphorylation of 1) cardiac troponin I (cTnI) in both LV regions, and 2) cardiac myosin-binding protein C (cMyBP-C) in the anterior wall. rRIC normalized pCa50, cTnI and cMyBP-C phosphorylations. Taken together, post-ischemic LV remodeling involves region-specific alterations in ACE and ACE2 activities together with changes in cardiomyocyte myofilament protein phosphorylation and function. rRIC has the potential to prevent these alterations and to improve LV performance following MI. 相似文献
14.
Hydrogen peroxide generation during contact of aqueous ozone with activated carbon surface is an established process. However, no systematic research concerning this phenomenon has been conducted. In this paper, factors affecting H2O2 generation are presented. Formation of hydrogen peroxide in contact of ozone with carbon is a surface phenomenon, strongly affected by the solution pH. Re-ozonation of the same carbon sample does not lead to H2O2 generation. Additionally, the amount of generated H2O2 is significant only in strongly acidic environment. It implies that hydrogen peroxide generated by surface of activated carbon cannot be ozone decomposition initiator in catalytic ozonation based on activated carbon as a catalyst. 相似文献
15.
Nowadays polyethylene is one of the polymers produced in the greatest volume and the amount of generated waste high-density polyethylene (w-HDPE) is significant as well. Valorization and recycling of w-HDPE can be realized by blending with different types of polymers and/or elastomers for example, ethylene-vinyl acetate (EVA). For the purpose of boosting of interfacial interactions between these two polymers experimental olefin-maleic-anhydride based additives have been incorporated into the blends after optimization of the processing temperature. Impact and tensile tests have been carried out in our research work besides microscopy measurements and investigation of the effects of additive structure by FT-IR and rheology. At higher processing temperature (220°C) both tensile properties and Charpy impact strength were increased, latter one improved by 245% measured at 5°C while elongation at break enhanced by 182% with incorporation of some experimental additives compared to the neat 70/30 w-HDPE/EVA. Changes in the hydrocarbon molecular chains of experimentally compatibilized blends were observed based on FT-IR results and rheological measurements. It can be concluded that one of the most basic notions of sustainability, the 4R's (reduce, recycle, reuse, recover) has been satisfied in a successful way. 相似文献
16.
The widespread use of anovulatory compounds and the well-known effects of sex hormones on various aspects of metabolism prompted
this review of our work and the work of others on observed changes in lipid metabolism resulting from the administration of
oral contraceptives and their components. In the rat, female sex hormone administration results in a decreased plasma cholesterol
level, an accumulation of cholesterol in liver and a decreased hepatic cholesterol biosynthesis. On the other hand, cholesterol
biosynthesis is enhanced in ovaries and adrenals. There is also a diminished alpha lipoprotein content and a corresponding
decrease in the alpha/beta lipoprotein ratio. In some cases these changes are comparable to those observed during pregnancy.
The results of sex hormone administration to women are more variable. In this case the most often observed effect is hypertriglyceridemia.
Changes in lipoprotein content and distribution are also evident and may be the result of changes in metabolism in the liver,
e.g., lipid synthesis or lipid transport from liver to plasma and tissues, or both. Many of these changes may be mediated
indirectly through the action of estrogenprogestin on other hormones. In both species the effects of oral contraceptives are
attributable principally to the estrogen component. The combination of estrogen with progestin compounds, which constitutes
the oral contraceptive, modifies the effects of estrogen administered alone. 相似文献
17.
Evaluation of colouring ability of main European elderberry (Sambucus nigra L.) varieties as potential resources of natural food colourants 下载免费PDF全文
Lilla Szalóki‐Dorkó Mónika Stéger‐Máté László Abrankó 《International Journal of Food Science & Technology》2015,50(6):1317-1323
Profiling and quantitative analysis of anthocyanins in five elderberry (Sambucus nigra L.) varieties, namely ‘Haschberg’, ‘Samocco’, ‘Samyl’, ‘Samident’ and ‘Sampo’, were performed in six different maturity stages from two consecutive years (2012 and 2013) and from two growing areas in Hungary. Cyanidin‐3‐O‐sambubioside‐5‐O‐glucoside, cyanidin‐3‐O‐sambubioside and cyanidin‐3‐O‐glucoside were found and identified by HPLC‐Q/TOF‐MS as major anthocyanins and were quantified by HPLC‐UV/Vis. In optimum maturity stage, ‘Samocco’ showed the highest anthocyanin content with an average of 1237 mg per 100 g dry weight in both growing areas and vintages. The dominant anthocyanin component of Samocco variety was cyanidin‐3‐O‐sambubioside, which is according to literature more stable against technology processing than cyanidin‐3‐O‐glucoside found in the other four investigated elderberry varieties in the highest concentration. ‘Samocco’, if grown under the climatic conditions of the Carpathian basin, might be a promising alternative variety for growing as raw material for natural food colourant processing industry. 相似文献
18.
Plenty of controversies have recently surrounded the mechanism and kinetics of ozone decomposition process in presence of activated carbon. We have decided to study and explain the source of these controversies, or at least identify it correctly. Several series of experiments were conducted and various parameters (activated carbon amount and grain size, initial ozone concentration, agitation speed) were modified over their course. It was found that widely accepted (pseudo)first-order kinetics cannot explain some observations, and the best fitting was found for half-order kinetics. Ozone decomposition mechanism explaining these results was proposed. 相似文献
19.
The cation exchange capacity (CEC) of porous zeolites allows to adsorb in the framework cavities the cations as pollutant heavy metal ions. We investigate the CEC behaviour of different zeolites in different experimental conditions; in solution where the ion's mobility is spontaneous and free and in the electrokinetic system where the ion's mobility is driven by the electric field. The aim of this study is to investigate if the CEC is an useful property to create a special interface region of zeolites, that if placed in the electrokinetic cell, just before the cathode, could allow to capture and concentrate the heavy metallic ions, during their migrating process. The zeolite 13X investigated in the electrokinetic proofs, retains a good high ions adsorption, even if quite smaller than the relevant free solution condition and well acts as confined trap for the heavy metal ions. In fact no trace of metallic deposition are present on the electrode's surface. 相似文献
20.
Roslyn B. Alfin-Slater Sheila Auerbach Lilla Aftergood 《Journal of the American Oil Chemists' Society》1959,36(12):638-641
Summary Soybean oil, cottonseed oil, and lard were heatedin vacuo for either 70 and/or 100 min. at 610°F. and were fed to male and female rats at a level of 15% in the diet over a complete
life span. Nutritional indices such as growth, including food efficiency and digestibility of the fats, reproduction and lactation,
longevity, and tissue cholesterol and total lipid were measured. No evidence of impaired nutrition or harmfulness was observed
in any group except in those fed the more highly polymerized soybean oil, where a decrease in iodine value of 10% and a 100%
increase in viscosity was associated with a slight depression in growth and an interference with reproductive performance
in the female animal. This interference with the reproductive process was alleviated by supplementation with α-tocopherol.
There was no evidence of increased tumor incidence in the groups ingesting the heated oils. Digestibility of the heated soybean
and cottonseed oils was only slightly reduced.
Presented at the fall meeting, American Oil Chemists' Society, Chicago, Ill., October 21, 1958.
Contribution No. 467. 相似文献