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21.
Gene expression pattern of digestive and antioxidant enzymes during the larval development of reared Atlantic bluefin tuna (ABFT), Thunnus thynnus L. 下载免费PDF全文
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OBJECTIVE: To assess the use of folic acid supplementation in relation to small-area measures of social deprivation. DESIGN: Cohort study. SETTING: Antenatal clinic, Women's Outpatients Services, Cumberland Infirmary, Carlisle, UK. SUBJECTS: Four hundred and fifty women attending their 18-week antenatal clinic appointment. No selection criteria were applied. Townsend scores were allocated using postcodes to provide a small-area measure (enumeration district) of social deprivation. RESULTS: Eighty-nine per cent of women took folic acid prior to their 18-week antenatal clinic appointment; 48% of women took folic acid before 4 weeks of gestation. Younger women and more socially deprived women were less likely to use folic acid supplements before 4 weeks of gestation. Women with a family history of neural tube defects were no more likely to take folic acid than were women with no family history of neural tube defects. CONCLUSION: A high proportion of women reported taking folic acid supplements during pregnancy but less than half took them at the most important time in early pregnancy. Younger women and women who were more socio-economically deprived were much less likely to take folic acid during the critical periconceptional period. Future strategies should promote prenatal folic acid supplementation in women under the age of 24 and in women of low socio-economic status. Further attention should also be given to the use of folic acid supplements in women with a family history of neural tube defects. 相似文献
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Changes in adherence to cardiopulmonary resuscitation guidelines in a single referral center from January 2009 to June 2013 and assessment of factors contributing to the observed changes 下载免费PDF全文
26.
Hennessy Louise M. Popay Alison J. Glare Travis R. Finch Sarah C. Cave Vanessa M. Rosts Michael 《Journal of pest science》2022,95(1):263-277
Journal of Pest Science - Argentine stem weevil adults (ASW, Listronotus bonariensis) feed on the leaves of agricultural grasses and their larvae mine the pseudostem, causing extensive damage that... 相似文献
27.
Dietary nano-chromium tripicolinate increases feed intake and decreases plasma cortisol in finisher gilts during summer 总被引:1,自引:1,他引:0
Alex Tsungyu Hung Brian Joseph Leury Matthew Allen Sabin Cherie Louise Collins Frank Rowland Dunshea 《Tropical animal health and production》2014,46(8):1483-1489
Chromium (Cr) is an essential mineral element and has been used in pig diets to improve growth performance, insulin sensitivity, immune response and carcase traits and to reduce heat or other stress responses. The aims of thiss study were to determine the impact of nano-sized chromium tripicolinate (nCrPic) on growth performance, feed efficiency and carcase characteristics of finisher gilts during the summer period. A total of 60 finisher Large White x Landrace gilts were stratified on initial weight and then within strata randomly allocated into two treatment groups in three replicates during mid-summer for 28 days. All pigs were housed in individual pens and had ad libitum access to feed and water. Pigs were fed either a control finisher diet (wheat-based diet containing 13.8 MJ digestible energy (DE) per kilogram and 0.56 g available lysine/MJ DE) or a control diet containing 400 ppb Cr as nCrPic. Dietary nCrPic supplementation increased feed intake by 6 % over the entire study (P?=?0.05). In particular, dietary nCrPic increased average daily feed intake (ADFI) by 8 % (P?=?0.02) during the final 2 weeks of the study. Moreover, dietary nCrPic tended to improve average daily feed (ADFI) over the entire study (P?=?0.09). However, there were no significant effects of nCrPic on feed conversion ratio (FCR), final weight, hot standard carcase weight (HCWT), P2 depth or dressing percentage. Plasma cortisol was decreased by 25 % (P?=?0.06) by dietary nCrPic supplementation. However, there were no effects of nCrPic on plasma glucose, insulin and nonesterified fatty acids (NEFA), might because of the higher feed intake. In conclusion, this study demonstrates that dietary nCrPic supplementation at 400 ppb can increase feed intake in finisher gilts during mid-summer, suggesting that nCrPic can ameliorate some of the negative effects of heat stress in pigs, possibly via decreased of circulating cortisol. 相似文献
28.
José F. Barbosa-Neto Carlos M. Hernández Louise S. O’Donoughue Mark E. Sorrells 《Euphytica》1997,98(1-2):59-67
Genetic progress through selection is directly related to the amount of variability present in the population and the quality
of genes contributed by the parents. Genetic relationships between lines were studied using DNA marker-based estimates of
genetic similarity. A statistical methodology using the width of a confidence interval was developed to determine the number
of probes to be surveyed and the precision in the estimation of genetic distance between pairs of cultivars. Precision was
affected by type of genetic distance used, the number of cultivars, and amount of genetic diversity present in the studied
group. The width of a (1-α)% confidence interval decreased as the number of RFLP fragments increased. Oat and wheat diversity
studies were used to illustrate the methodology.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
29.
We report a conceptual framework for a simple screening tool to evaluate the vulnerability of different fields in the landscape to phosphorus (P) loss within the European agricultural context. Our work builds on the principles established for the P Index system developed in the United States. We examine the differing needs and criteria for a range of EU member states and EFTA countries and highlight essential and optional criteria for inclusion in the decision support framework depending on their ecoregional characteristics. A framework such as this, meets in principle, the needs of the COST832 Action ‘Quantifying the Agricultural Contribution to Eutrophication’ as it deals with diffuse nutrient sources from agriculture, and aids more targeted use of practical strategies to mitigate nutrient losses to minimise the potential for the eutrophication of receiving waters. 相似文献
30.
Beow?Yong?YeapEmail author Paul?J.?Catalano Louise?M.?Ryan Marie?Davidian 《Journal of Agricultural, Biological & Environmental Statistics》2003,8(4):438-454
A robust two-stage approach is used to reanalyze the repeated measurements from an experiment of airway responsiveness in
rats randomized to long-term exposure at four ozone doses. The concentration-response data generated for each rat may be represented
as a hierarchical nonlinear model encompasing the sources of variation within and between individual profile for each rat,
the conditional modeling approach can assess the adequacy of an assumed mean model, a fundamental advantage not intrinsic
to marginal techniques. The two-stage population inference is based on the estimated individual parameters, thus maintaining
an intuitive appeal to the toxicologists who traditionally have fitted a separate curve for each animal and then applied ANOVA
to the summary statistics. However, we formally adjust the standard errors for the extra variability due to the initial estimation
of the individual parameters and also allow for their within-rat correlation. The robust two-stage method appropriately down
weights the a berrant responses arising sporadically within individualsand, more importantly, the rats which may be outlying
relative to the usual population variation. The true effect of chronic ozone exposure, including a significant gender interaction,
may be masked by a few rats which exert undue influence on the population estimates in a nonrobust analysis. 相似文献