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991.
Ageing is associated with reduced energy intake and loss of appetite. Older men tend to have poorer dietary intakes including consumption of fewer fruits and vegetables in comparison to older women. Living and eating alone further diminishes food consumption and dietary quality. The aim of the present study was to explore food choice and energy intake in older men living alone using both quantitative and qualitative methods. 39 older men were interviewed and completed questionnaires on health, food choice, dietary patterns and appetite. Few men managed to consume recommended levels of energy, essential trace elements or vitamins A and D. Age and BMI failed to predict patterns of intake, but men with good cooking skills reported better physical health and higher intake of vegetables. However, cooking skills were negatively correlated with energy intake. Men who managed to consume at least 4 portions of fruits and vegetables each day had significantly higher vitamin C levels, a greater percentage of energy as protein and generally more adequate diets. Interviews revealed that poor cooking skills and low motivation to change eating habits may constitute barriers to improving energy intake, healthy eating and appetite in older men (193). 相似文献
992.
Expression of heterologous antigens in Salmonella Typhimurium vaccine vectors using the in vivo-inducible, SPI-2 promoter, ssaG 总被引:1,自引:0,他引:1
McKelvie ND Stratford R Wu T Bellaby T Aldred E Hughes NJ Chatfield SN Pickard D Hale C Dougan G Khan SA 《Vaccine》2004,22(25-26):3243-3255
DNA derived from regions upstream of the Salmonella enterica serovar Typhimurium ssaG gene were used to drive expression of different reporter genes in putative Salmonella vaccine strains. Expression from ssaG was shown to be significantly upregulated once Salmonella had entered murine or human macrophages, and levels of expression were dependent on the length of the ssaG 5' sequence incorporated. S. Typhimurium derivatives harbouring the Escherichia coli heat labile toxin B subunit (LT-B) fused to various lengths of the ssaG promoter region were also constructed as single copy chromosomal integrations. Expression of LT-B by these Salmonella derivatives was detected at significant levels after intra-macrophage survival and mice immunised with these derivatives mounted marked anti-LT-B humoral antibody responses. 相似文献
993.
King LJ Marano N Hughes JM 《Revue scientifique et technique (International Office of Epizootics)》2004,23(2):717-725
As Veterinary Services and animal health organisations attempt to respond to a new era of emerging and re-emerging zoonotic diseases, their ability and skill in forming new strategic partnerships will be paramount. While these new partnerships are likely to include many relationships outside traditional Veterinary Services and animal agriculture, none will become more important than the formation of new animal health and public health partnerships. Episodes of emerging zoonoses are being increasingly recognised around the world and the confluence of people, animals and animal products today is unprecedented. Concurrently, a wide array of complex factors are also converging that will not only ensure the continuous emergence of zoonoses, but are also likely to drive the further increase and expansion of these diseases. This article discusses the need for the creation of more effective and co-operative partnerships in the face of new microbial threats, the complexity of both the formation and expansion of zoonoses, and the collective abilities of both human and animal health services to respond to them. Lessons learned from recent zoonotic epidemics supportthe need for co-ordinated research, interdisciplinary centres, integrated surveillance systems, response systems and infrastructures, and workforce development strategies. While there are some excellent examples of collaborative animal and public health relationships, there is no question that more and stronger partnerships among national and international organisations, both academic and private, will be necessary to meet the future challenges of emerging zoonoses and to manage their profound implications. 相似文献
994.
A stoichiometric equation and kinetic model were developed and validated using experimental data from batch respirometer studies on the biodegradation of 2,4-dinitrotoluene (DNT). The stoichiometric equation integrates bacterial energetics and is revised from that in a previous study by including the mass balance of phosphorus (P) in the biomass. Stoichiometric results on O2 consumption, CO2 evolution, and nitrite evolution are in good agreement with respirometer data. However, the optimal P requirement is significantly higher than the stoichiometrically derived P, implying potentially limited bioavailability of P and the need for buffering capacity in the media to mitigate the adverse pH effect for optimal growth of DNT-degrading bacteria. An array of models was evaluated to fit the O2/CO2 data acquired experimentally and the DNT depletion data calculated from derived stoichiometric coefficients and cell yield. The deterministic, integrated Monod model provides the goodness of fit to the test data on DNT depletion, and the Monod model parameters (Ks, X0, mumax, and Y) were estimated by nonlinear regression. Further analyses with an equilibrium model (MINTEQ) indicate the interrelated nature of medium chemical compositions in controlling the rate and extent of DNT biodegradation. Results from the present batch respirometer study help to unravel some key factors in controlling DNT biodegradation in complex remediation systems, in particular the interactions between acidogenic DNT bacteria and various parameters, including pH and P, the latter of which could serve as a nutrient, a buffer, and a controlling factor on the bioavailable fractions of minerals (Ca, Fe, Zn, and Mo) in the medium. 相似文献
995.
996.
Witt KL Hughes LA Burka LT McFee AF Mathews JM Black SL Bishop JB 《Environmental and molecular mutagenesis》2003,41(2):111-120
N-Hydroxymethylacrylamide (NHMA), a mouse carcinogen inactive in the Salmonella assay and mouse micronucleus (MN) assay, was tested for reproductive effects in a mouse continuous breeding study. In that study, increased embryonic deaths were observed after 13 weeks exposure of parental animals to NHMA via drinking water (highest dose, 360 ppm); the results indicated the possible induction of chromosome damage in germ cells of treated males. An additional mouse MN test was conducted using a 31-day treatment period to better match the dosing regimen used in the breeding study; the results were negative. Additional studies were conducted to explore the germ cell activity of NHMA. A male mouse dominant lethal study was conducted using a single intraperitoneal injection of 150 mg/kg NHMA; the results were negative. A follow-up study was conducted using fractionated dosing, 50 mg/kg/day for 5 days; again, no increase in dominant lethal mutations was observed. NHMA (180-720 ppm) was then administered to male mice in drinking water for 13 weeks, during which three sets of matings occurred. Two weeks after mating, females were killed and the uterine contents were analyzed. Large, dose-related increases in dominant lethal mutations were observed with increasing length of exposure. The magnitude of the increases stabilized after 8 weeks of treatment. However, the frequency of micronucleated peripheral blood erythrocytes was not elevated in mice treated for 13 weeks with NHMA in drinking water. Thus, NHMA appears to be unique in inducing genetic damage in germ cells but not somatic cells of male mice. 相似文献
997.
998.
999.
Mao C Hughes JP Kiviat N Kuypers J Lee SK Adam DE Koutsky LA 《American journal of obstetrics and gynecology》2003,188(3):677-684
OBJECTIVE: The purpose of this study was to identify clinical signs and symptoms associated with detection of human papillomavirus (HPV) DNA in the female genital tract. STUDY DESIGN: A total of 516 university students (18 to 24 years old) enrolled in a cohort study that included the collection of genital specimens for HPV DNA testing every 4 months for up to 4 years. Reported symptoms and objective clinical findings of women with and without HPV DNA were compared by multivariate analysis. RESULTS: Acute and persisting HPV infections were not associated with discharge, itching, burning, soreness, or fissures. Clinical evidence of genital warts was statistically associated only with HPV types 6 and 11. Detection of any HPV DNA was associated with bacterial vaginosis (BV). Furthermore, a time lag analysis suggests that HPV infection usually precedes detection of BV. CONCLUSION: Most women who acquire genital HPV infection are asymptomatic; some, however, are at increased risk for BV. 相似文献