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91.
Aspergillus parasiticus was inoculated into grapefruit juice and a glucose-yeast extract medium; both contained 500-7000 ppm of citrus oils that were incorporated into the media by sonication. Orange and lemon oil were more inhibitory to mold growth and aflatoxin production than was dlimonene, the main constituent of the two peel oils. After 7 days at 28 degrees C, 2000 ppm of lemon and 3000 ppm of orange oil in grapefruit juice afforded maximum suppression of mold growth and toxin formation. When the glucose-yeast extract medium was used, 3000 ppm of either oil were needed to achieve the same result. After 4 days at 28 degrees C, orange oil at 3500 ppm in either medium markedly inhibited mold growth (as evidenced by dry weight of mold mycelium) and aflatoxin production (only 14 and 1% of the amount normally produced in the juice and artificial medium, respectively). Higher concentrations of orange oil further reduced mold growth and aflatoxin production and also delayed the onset of sporulation, if it occurred. Although aflatoxin was detected in all samples, only 0.2 to 0.5% of the amount found in controls (without the citrus oil) was present when the medium contained 7000 ppm orange oil. The mold consistently grew, albeit very poorly, on the glass at the liquid-atmosphere interface even when the substrate contained a large amount of citrus oil.  相似文献   
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Fasting plasma free amino acids were determined in 54 convalescent malnourished infants: seven infants while consuming a diet based on isolated soybean protein, containing 4.0% to 5.3% of dietary metabolizable energy (calories) as protein (A), 20 at 6.4% to 6.7% protein calories (B), 23 at 6.4% to 6.7% protein calories with added DL-methionine (C), and four with 8.0% to 12.3% protein calories (D). There were no differences in total amino acid concentration (TAA) among the four groups; the molar fraction of essential amino acids (EAA:TAA) was lower for group A; there were no differences among the four groups in Lys:EAA or 1/2 cystine:EAA ratios or in Met concentration. Met:EAA was higher in C than B, with considerable overlap of individual values. In 10 of 13 infants who were represented in both B and C, Met concentration and Met:EAA ratio were higher in group C. Fasting plasma AA levels are not consistently reliable for field or clinical assessment of dietary Met adequacy. Fasting and postprandial (3- and 4-hour) plasma AA were determined in 29 infants: in 12 the preceding diet and the test meal were both Met-deficient with less than 6.7% protein calories (E), in five the preceding diet was milk-based but the test meal was Met-deficient at less than 6.7% (F), in five the preceding diet and test meal were based on isolated soybean protein at less than 6.7% with DL-Met added (G), and in seven the test meal was soy-based with greater than 9.0% protein calories (H). Plasma Met concentration and Met:EAA fell significantly at 3 and 4 hours in groups E and F, but not in groups G and H, suggesting that a postprandial fall in Met:EAA ratio can be used to identify dietary Met deficiency in field situations.  相似文献   
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A 59-week study was conducted to evaluate the impact of adult Mesocyclops longisetus populations on larval mosquito species inhabiting tires. Greater than 90% reduction of number of 1st and 2nd instars was recorded by 4 wk with 90% reduction of number of 3rd and 4th instars after 7 wk. Reduced control was noted with the onset of cooler winter water temperature. Overall. a 52% reduction in the number of 1st and 2nd instars was achieved, and a 57% reduction was noted in number of 3rd- and 4th-instar mosquito larvae. Cooler temperatures resulted in a decline of adult Mesocyclops, which resulted in reduced larval control. Significantly greater numbers of Mesocyclops adults were collected in tires with either new litter or heavy amounts of litter regardless of litter type. Lastly, litter type, either oak leaves or pine needles, did not influence mosquito reduction or abundance of Mesocyclops populations.  相似文献   
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The effects of the bacterial endotoxin lipopolysaccharide (LPS) and interleukin (IL)-1beta on corticosterone secretion has been studied in vivo by employing the technique of in situ perfusion of the isolated rat left adrenal gland. Both LPS and IL-1beta dose-dependently raised corticosterone output, the response peaking at 60 and 90 min, respectively. IL-1 receptor antagonist dose-dependently reversed the effect of LPS and IL-1beta. The IL-1beta converting enzyme (ICE) inhibitor Ac-YVAD-CMK annulled the adrenal response to LPS, but did not affect that to IL-1beta. Collectively, these findings provide evidence that LPS, by enhancing adrenal production of IL-1beta, is able to evoke a sizable glucocorticoid response in the rat, thereby suggesting that local immuno-endocrine interactions may be operative in the adrenal gland of this species.  相似文献   
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Heterotopic ossification (HO) after femoral intramedullary rodding is a significant complication of the procedure. One hundred eighteen cases of femoral roddings performed on 113 patients were available for review. The data were computerized and evaluated using univariate analysis and multivariate regression analysis. A statistically significant increase of HO was found with male gender, increased delay to surgery, and in patients requiring prolonged intubation because of their multiple injuries. HO was classified using a modified version of the method of Brumback et al. (grades 0-IV). A strong correlation of HO with brain injury documented by computed tomography scan was also found to be statistically significant for the more severe grades of HO. This group of patients had not previously been identified as being at high risk for HO.  相似文献   
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OBJECTIVE: The American Diabetes Association (ADA) has recommended that the fasting plasma glucose (FPG) level used to diagnose diabetes be changed from 7.8 mmol/l (the level recommended by the National Diabetes Data Group [NDDG] in 1979) to 7.0 mmol/l. We examined the impact of this change on rates of progression to overt diabetes from different levels of FPG. RESEARCH DESIGN AND METHODS: Using the laboratory database of Mayo Clinic, we assembled a cohort of 8,098 nondiabetic Olmsted County residents 40 years of age or older on 1 July 1983. Subjects were followed for a median of 9 years. RESULTS: Among 7,567 individuals with follow-up FPG data, 778 (10.3%) progressed to ADA diabetes and 513 (6.8%; P < 0.0001) progressed to NDDG diabetes. The risk of developing ADA diabetes was 7, 19, and 39% for individuals with initial FPG values in the ranges of <5.6, 5.6-6.0, and 6.1-6.9 mmol/l, respectively. For progression to NDDG diabetes, the respective risks were 3, 11, and 25%. A clear gradient of risk was observed within the "normal" range of FPG (<5.6 mmol/l). Among the 793 individuals who developed ADA diabetes, 222 (29%) developed NDDG diabetes simultaneously and 291 (37%) developed NDDG diabetes later. In all FPG subgroups, progression to ADA diabetes occurred approximately 7 years sooner than progression to NDDG diabetes. CONCLUSIONS: The baseline level of FPG is a major predictor of an individual's risk of developing diabetes. The proposed change in the diagnostic criteria for diabetes will lead to earlier diagnosis among individuals who are destined to develop the disease.  相似文献   
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