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101.
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Elin Hallén Toomas Allmere Anne Lundén Anders Andrén 《International Dairy Journal》2009,19(6-7):399-404
Individual milk samples from 80 cows in mid-lactation of the Swedish Red and Swedish Holstein breeds with known protein genotypes of β- and κ-casein and β-lactoglobulin were analysed for acid coagulation properties. Glucono-δ-lactone (1.5%) was added to defatted, heated (90–95 °C) samples and rheological properties of the gels were measured using a Bohlin VOR Rheometer. Coagulation time (CT) and curd firmness after 4, 8 and 10 h (G4′, G8′, and G10′ were registered for each sample. Milk protein composition was analysed by reversed phase HPLC. Concentration of β-lactoglobulin in milk was found to be an important factor for the variation in CT and G′. The A allele of β-lactoglobulin was associated with higher concentrations of β-lactoglobulin in milk compared with B. When no adjustment for β-lactoglobulin concentration was made, there was a significant overall effect of β-lactoglobulin genotype on acid coagulation, where the AA and AB genotypes were associated with better curd firmness compared with BB, whereas at equal β-lactoglobulin concentrations a tendency in the opposite direction was found with a significant and positive effect of BB compared with AB. Lactose concentration of milk had a positive effect on acid coagulation and was shown to improve G′ in milk with low β-lactoglobulin concentrations. 相似文献
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Background
Smoking is common in young people, particularly in disadvantaged groups, and continued smoking has a major impact on quality and quantity of life. Although many young smokers want to stop smoking, little is known about the design and effectiveness of cessation services for them.Objective
To determine whether nicotine replacement therapy (NRT) when combined with counselling is effective in young smokers in a deprived area of Nottingham, UKMethods and subjects
We surveyed smoking prevalence and attitudes to smoking and quitting in young people accessing an open access youth project in a deprived area of Nottingham, and used the information gained to design a community based smoking cessation service incorporating a randomised controlled trial of nicotine patches against placebo given in association with individual behavioural support. We resurveyed smoking prevalence among project attendees after completing the pilot study.Results
Of 264 young people surveyed (median age 14 years, range 11–21), 49% were regular smokers. A total of 98 young people were recruited and randomised to receive either active nicotine patches on a six week reducing dose regimen (49 participants), or placebo (49 participants). Adherence to therapy was low, the median duration being one week, and 63 participants did not attend any follow up. At four weeks, five subjects receiving active NRT and two receiving placebo were abstinent, and at 13 weeks none were. Adverse effects were more common in the active group but none were serious. Smoking prevalence among 246 youth project attendees surveyed after the trial was 44%.Conclusions
This study suggests that NRT in this context is unlikely to be effective in young smokers, not least because of low adherence to therapy. It also suggests that young smokers want help with smoking cessation, but that establishing the efficacy of smoking cessation services for young people who need them most will be very difficult. 相似文献105.
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Hand force is a known risk factor for upper extremity disorders. The objective of the present study was to determine the characteristics of, and the relationships between, exposure assessment methods to quantify hand force. Five methods, used in the laboratory or the field, were used to quantify hand force at three force magnitudes: two direct (or technical) measurement methods, force transducers and electromyography; an observational method; and two self-report approaches, force matching and a visual analogue scale. Five tasks, simulating manual work activities, were performed by 20 participants. The coefficients of variation of measures within and between participants were moderate. All approaches clearly distinguished between the three force levels tested. The reliability of the methods ranged from poor (observation method without information) to good (force transducers method and observation method with information). The measurement methods correlated moderately over all five tasks. Predictions of grip force across all five tasks were poor and even for single tasks the predictions were not much better. The tasks in this study were still simplified; in the field tasks are even more complex and the measurement characteristics might be expected to be less good. A hand force exposure assessment method should therefore be calibrated and tested for each type of hand activity before use. 相似文献
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Ekstrøm PO Bjørge T Dørum A Longva AS Heintz KM Warren DJ Hansen S Gislefoss RE Hovig E 《Analytical chemistry》2004,76(15):4406-4409
Analysis of DNA variation in biological samples most frequently utilizes the polymerase chain reaction (PCR) performed on extracted genomic DNA, followed by visualization of alleles using various methodologies. Few reports have demonstrated that amplification of DNA from plasma and serum samples is possible. We have performed DNA amplification on a large set of serum samples (n = 2955). Here, we report that known hereditary mutations in the BRCA gene can efficiently be analyzed in serum samples collected and stored over several decades. Fragments were PCR-amplified following a short initial denaturation of the serum sample in a standard microwave oven. Fragment analysis was subsequently performed using a DNA capillary-sequencing instrument. The PCR success rates were fragment- and size-dependent ranging from 83.2% to 97.9%. Of the 11,820 polymerase chain reactions performed, the overall PCR success rate was 91.3% (10,796/11,820), which is comparable to PCR performed on genomic DNA. The advantage of the method described herein is its ability to utilize archival material stored in serum biobanks for long periods of time. 相似文献
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An estimation of the heavy metal and anion mass-balance was made for municipal solid waste incinerator bottom ash deposited at a construction and industrial waste landfill. The mass-balance was found by comparing the content of metals and anions in the landfill leachate to the metal and anion content in the deposited bottom ash. The discharge of heavy metals ranged from 0.001% for Pb to 0.55% for Cr, which is approximately at the same level as in regular municipal solid waste (MSW) landfills. Landfilled organic material and silicates from construction waste might have contributed to the retention of metals. Chloride, and to a lesser extent sulphate, appeared to be readily released from the landfill. It was estimated that a mass corresponding to 80% of the Cl- and 18% of the SO(4)2- in the bottom ash was discharged annually. Low retention, especially of chloride, may lead to a rapid decline in the discharge of this ion in the future when the landfilling of bottom ash is discontinued. 相似文献
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