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31.
The aim of the study was to examine whether smoking reduction over a 6-year period (1975-1981) predicted smoking cessation 9 years later by 1990. The longitudinal data from three surveys over 15-year period among the Finnish adult twin cohort were used. The data were collected by postal surveys in 1975, 1981, and 1990, and the sample comprised 11,015 participants, of whom 2,443 were persistent current smokers in 1975 and 1981. Smoking cessation by 1990 was examined as the outcome measure. Nineteen percent reported having stopped smoking by 1990, corresponding to an approximate annual rate of smoking cessation of 2%. Those who had quit smoking by 1990 had larger decreases in smoking between 1975 and 1981. The odds ratio for quitting by 1990 increased with increasing levels of reduction in amount smoked between 1975 and 1981. This was found in both categorical and trend analyses, and when adjusting for age, sex and for amount of baseline smoking. The model among twin pairs discordant for cessation indicated that the association of smoking reduction with increased likelihood of cessation was independent of genetic or early shared family influences on smoking behavior. We conclude that smokers who are able to decrease the number of cigarettes smoked per day by at least 25% are more likely to quit later. 相似文献
32.
Tarhuni N.G. Korhonen T.O. Mutafungwa E. Elmusrati M.S. 《Lightwave Technology, Journal of》2006,24(2):694-704
Optical code division multiple access (CDMA)-based networks are an interesting alternative to support various traffic types of multimedia applications with highly variable performance targets. Generally, multilength codes are designed to support multirate services, while the multiweight codes are designed to support differentiated quality of service (QoS) for multimedia applications. However, existing optical orthogonal codes (OOCs) are limited to single class or multiclass with restricted weight and length properties. Therefore, there exists a lack of flexibility in the existing OOCs to support arbitrary rate and QoS. This paper presents a proposal of generation procedure and performance analysis of joint multiweight multilength strict OOCs. The approach used in this paper is to apply a methodology strongly relying on developed analytical theory that is supported by computer optimization, because it has turned out that it is mathematically intractable to construct unconstraint joint multilength multiweight OOCs using pure algebraic techniques. The generated code set fulfills the conditions of strictly OOCs, namely, the maximum nonzero shift autocorrelation and the maximum cross correlation constraints of one. The mark position difference (MPD) approach is used to generate in a flexible way the multiclass code set. The MPD results in the simple evaluation of multiclass code set cardinality. Furthermore, the multiple-access interference (MAI) in a multiclass OOC system is evaluated by modeling the interference per class as a Poisson distribution to simplify performance evaluation with acceptable accuracy. 相似文献
33.
A case of chronic ulcer of the lower lip, which persisted for three years and resisted all locals treatments, is presented. Recovery was achieved with excision. The specimen was examined macroscopically, and showed a prominent inferior labial artery or calibre-persistent artery, an uncommon entity. Patient-literature was reviewed. 相似文献
34.
Mattila E. Parkka J. Hermersdorf M. Kaasinen J. Vainio J. Samposalo K. Merilahti J. Kolari J. Kulju M. Lappalainen R. Korhonen I. 《IEEE transactions on information technology in biomedicine》2008,12(4):501-512
35.
36.
Five Finnish ruminally cannulated Ayrshire cows were used in a 5 x 5 Latin square trial with 14-d periods to determine whether branched-chain amino acids (AA) are the second- or colimiting AA for milk protein synthesis on grass silage-cereal based diet. Mammary metabolism of AA as well as AA supply from the basal diet were also studied. Grass silage (17.5% crude protein) was given ad libitum with 9 kg/d as a cereal-based concentrate (13.8% crude protein). Treatments were basal diet without AA infusion (Control), abomasal infusion of AA mixture of His, Ile, Leu, and Val at 8.5, 14.9,27.9, and 18.3 g/d, respectively, AA mixture minus Ile, AA mixture minus Leu, and AA mixture minus Val. Glucose was infused on all treatments at 250 g/d. Amino acid infusions had no effect on dry matter intake (mean 19.2 kg/d), yields of milk (mean 25.3 kg/d), energy-corrected milk (mean 25.9 kg/d), milk protein (mean 807 g/d), lactose (mean 1261 g/d), or fat (mean 1056 g/d). Milk composition was not affected by the treatments. Plasma concentrations of His and Val responded to AA infusions but concentration of Ile increased only on treatment AA mixture minus Leu, and concentration of Leu only on treatment AA mixture minus Ile. Infusion of AA mixture of His, Ile, Leu, and Val decreased plasma concentrations of Arg, Lys, Met, Phe, and Tyr. Amino acid infusions did not affect concentrations of plasma urea and energy metabolites or AA utilization by the mammary gland. Based on unchanged production parameters, the supply of His or branched-chain AA seemed not to be limiting under the current dietary conditions. Changes in plasma AA concentrations suggest either antagonism between individual AA in absorption or increased partitioning of AA into the muscle tissues. About 75% of omasal canal nonammonia nitrogen flow (427 g/d) was of microbial origin, and AA profiles of microbial protein and omasal canal digesta were fairly similar. Postruminal AA supply seems to be dependent on the basal diet, but variation may exist even within the similar basal diets. 相似文献
37.
Vesterlund S Vankerckhoven V Saxelin M Goossens H Salminen S Ouwehand AC 《International journal of food microbiology》2007,116(3):325-331
The widespread use of immunosuppressive therapy and antimicrobial agents as well as novel probiotics without a long history of safe use has increased requirements for safety assessment of probiotic lactobacilli. In this study 44 faecal, 52 blood and 15 probiotic isolates (including 3 dairy strains) of Lactobacillus were assayed for their adhesion properties to extracellular matrix proteins and mucus, hemolysis, ability to avoid the induction of respiratory burst in peripheral blood mononucleocytes (PMN) and resistance to human serum. Among tested strains adhesion to collagen, fibrinogen and mucus was isolate-specific and no statistically significant differences were obtained between faecal, blood and probiotic isolates. However, blood isolates showed a trend for higher adhesion to mucus than probiotic strains (P=0.07). Probiotic strains induced lower respiratory burst in PMN when compared to the blood isolates (P<0.05). Moreover, there was a positive correlation between adhesion to collagen and induction of respiratory burst for faecal isolates (P<0.05). In the determination of serum resistance, probiotic strains showed a trend for lower sensitivity to human serum-mediated killing when compared to the faecal isolates (P=0.07). None of the measurable virulence factors were found to be present at statistically higher level in clinical blood isolates when compared to faecal and/or probiotic isolates indicating that these factors do not cause risk when safety of probiotics is considered. However, the significance of adhesion to mucus, low induction of respiratory burst in PMN and resistance to human serum-mediated killing may need further evaluation in experimental animal models and in epidemiological data. 相似文献
38.
Mannans as stabilizers of oil-in-water beverage emulsions 总被引:1,自引:0,他引:1
The stabilizing effect of spruce galactoglucomannan (GGM) on a model beverage emulsion system was studied and compared to that of guar gum and locust bean gum galactomannans, konjac glucomannan, and corn arabinoxylan. In addition, guar gum was enzymatically modified in order to examine the effect of the degree of polymerization and the degree of substitution of galactomannans on emulsion stability. Use of GGM increased the turbidity of emulsions both immediately after preparation and after storage of up to 14 days at room temperature. GGM emulsions had higher turbidity than the emulsions containing other mannans. The initial turbidity increased with increasing GGM content, but after 14 days storage at room temperature, the turbidity was the highest for GGM/oil ratio of 0.10:1 when ethanol-precipitated GGM was used. Increasing the storage temperature to +45 °C led to rapid emulsion breakdown, but a decrease in storage temperature increased emulsion stability after 14 days. Confocal microscopy showed that the average particle size in the bottom part of GGM emulsions stored for 14 days was smaller than 1 μm. A low degree of polymerization and a high degree of substitution of the modified galactomannans were associated with a decrease in emulsion turbidity. 相似文献
39.
Ross Crittenden Sirpa Karppinen Suvi Ojanen Maija Tenkanen Richard Fagerstrm Jaana Mtt Maria Saarela Tiina Mattila‐Sandholm Kaisa Poutanen 《Journal of the science of food and agriculture》2002,82(8):781-789
A range of probiotic and other intestinal bacteria were examined for their ability to ferment the dietary fibre carbohydrates β‐glucan, xylan, xylo‐oligosaccharides (XOS) and arabinoxylan. β‐Glucan was fermented by Bacteroides spp and Clostridium beijerinckii but was not fermented by lactobacilli, bifidobacteria, enterococci or Escherichia coli. Unsubstituted xylan was not fermented by any of the probiotic bacteria examined. However, many Bifidobacterium species and Lactobacillus brevis were able to grow to high yields using XOS. XOS were also efficiently fermented by some Bacteroides isolates but not by E coli, enterococci, Clostridium difficile, Clostridium perfringens or by the majority of intestinal Lactobacillus species examined. Bifidobacterium longum strains were able to grow well using arabinoxylan as the sole carbon source. These organisms hydrolysed and fermented the arabinosyl residues from arabinoxylan but did not substantially utilise the xylan backbone of the polysaccharide. Arabinoxylan was not fermented by lactobacilli, enterococci, E coli, C perfringens or C difficile and has potential to be an applicable carbohydrate to complement probiotic Bif longum strains in synbiotic combinations. © 2002 Society of Chemical Industry 相似文献
40.
Although fatty acid composition is the most important attribute used to control oxidation stability, all edible oils are affected by lipid oxidation irrespective of whether they are highly unsaturated or not. The aim of the study was to compare the oxidation of rapeseed oil (RO) and butter oil (BO) triacylglycerols (TAGs) and their mixtures containing 10% or 20% of the other. Oxidation of the TAGs at 40°C was followed by formation of primary and secondary products. Statistical methods were used to interpret the data. The RO and BO TAGs and their mixtures began to oxidise without any induction periods. In the RO TAGs more hydroperoxides and p‐anisidine reactive compounds were formed than in the BO TAGs. The BO TAGs oxidised more than would be expected by their fatty acid composition. High susceptibility of BO TAGs to oxidation was caused by the easy breakdown of their hydroperoxides. Heptadienal and heptenal were specific products of oxidised RO TAGs and heptanal and nonenal of oxidised BO TAGs. Mixtures of RO and BO TAGs behaved according to which was dominant in the mixture. However, as little as 10% of RO or BO TAG introduced its specific oxidation products to the mixture. © 1999 Society of Chemical Industry 相似文献