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301.
M. Dean R. Shepherd A. Arvola M. Vassallo M. Winkelmann E. Claupein L. Lähteenmäki M.M. Raats A. Saba 《Journal of Cereal Science》2007
Using a survey, this study investigated public perceptions relating to different healthy grain foods (bread, pasta and biscuits) and how these perceptions are influenced by gender, nationality, base product (staple vs. fun food), type of health claim (general vs. specific) and people's perceptions associated with different production methods. Two thousand and ninety-four (50.4% women, 49.5% men) members of the public from the UK, Italy, Finland and Germany completed the survey questionnaire. The participants were over 18 years of age and were solely or jointly responsible for the family's grocery shopping. 相似文献
302.
MA Stornelli JC Reyna MC Stornelli R Nuñez Favre CA Savignone CM Tittarelli RL de la Sota 《Reproduction in domestic animals》2009,44(S2):287-290
The aim of this study was to asses the variation in the morphology of the seminal epithelium in relation to natural photoperiod in male cats. Tom cats (n = 240) were castrated every other week throughout the year. Each testis was fixed in Bouin's solution and cut into sections. The percentage of tubules with round spermatids (RS), elongated spermatids (ES), tailed spermatids (TS), mature spermatids (MS) and the number of Sertoli cells (SC) and Leydig cells (LC) were recorded in each sample. Testicles from males during short days (SHD) had a higher percentage of tubules with RS and ES compared to testicles from males during long days (LHD, 31.3 ± 0.6 vs 2.1 ± 0.6%, p < 0.001; 30.9 ± 0.7 vs 11.0 ± 0.7%, p < 0.001). Conversely, testicles from males during SHD had a lower percentage of tubules with TS and MS compared to testicles from males during LHD (24.5 ± 0.8 vs 29.7 ± 0.8%, p < 0.01; 13.1 ± 1.2 vs 57.0 ± 1.2%, p < 0.01). Furthermore, testicles from males during SHD had a higher number of SC and lower number of LC compared to testicles from males during LHD (11.4 ± 0.1 vs 8.0 ± 0.1%, p < 0.01; 19.2 ± 1.0 vs 38.0 ± 1.0%, p < 0.01). In conclusion, there are seasonal changes in testis cell morphology in the tom which may be related to seasonal sperm production. 相似文献
303.
F Martínez-Pastor M del Rocío Fernández-Santos ÁE Domínguez-Rebolledo MC Esteso JJ Garde ; Biology of Reproduction Group 《Reproduction in domestic animals》2009,44(3):424-431
The assessment of sperm chromatin status is compulsory in a complete spermiogram. Here we applied the sperm chromatin structure assay (SCSA) and the sperm chromatin dispersion (SCD) test to assess the chromatin status of three fighting bulls. Cryopreserved semen (two straws/bull) were analysed by duplicate after thawing and after 6 h at 37°C with and without oxidative stress (1 m m FE2+ ). Results (SCD: percentage of spermatozoa with halo; SCSA: SD-DFI, %DFI and HDS) were analysed for differences between bulls and treatments, sensitivity and specificity (receiver operating characteristic curves) and repeatability (repeatability coefficients as 2SD of duplicate differences).%DFI for the three bulls was below 2% at 0 h, indicating no risk for fertility according to previous reports. It increased slightly for two of the bulls after FE2+ treatment (%DFI < 5%) and more pronouncedly for the other bull (C, %DFI∼10%), which merits further investigation. SCD rendered higher percentage of halos for bull C, but could not discriminate between samples with and without oxidizing treatment (AUC: 0.52). SCSA (%DFI) showed a high discriminating ability between treatments (AUC: 0.96). The repeatability coefficient was also higher for SCD (5.9) than for %DFI (1.8), indicating lower repeatability for SCD. Overall, %DFI might be the most useful parameter for assessing sperm chromatin on fighting bull. SCD might yield different information than SCSA, hence further research is warranted. 相似文献
304.
Muir JG Shepherd SJ Rosella O Rose R Barrett JS Gibson PR 《Journal of agricultural and food chemistry》2007,55(16):6619-6627
Fructans are not digested in the small intestines of humans. While many health benefits have been attributed to these carbohydrates, they can cause gastrointestinal symptoms in some individuals. We measured the total fructans in 60 vegetables and 43 fruits using the Megazyme fructan assay. Vegetables with the highest quantity of fructans included garlic, artichoke, shallots, leek bulb, and onions (range, 1.2-17.4 g/100 g fw). Fruits with low, but detectable, fructans included longon, white peach, persimmon, and melon (range, 0.21-0.46 g/100 g fw). The fructan assay was modified to provide an estimate of the average chain length (degree of polymerization) for high fructan vegetables. d-Fructose can also be malabsorbed in the small intestine of humans, so the d-fructose content in some foods was measured to supplement the current food tables. Research in this area will be facilitated through the availability of more comprehensive food composition data. 相似文献
305.
Jonathan Shepherd Enrico Bachis 《Aquaculture Economics & Management (Blackwell Science)》2013,17(4):395-416
Competition for fish oil from human nutritional supplements (nutraceuticals) is starting to threaten its supply for aquaculture feeds. World supply of fish oil is not increasing but is the main source of healthy omega-3 fats (n-3 LC-PUFA). Fish oil demand by nutraceuticals is a derived demand for such fats. Demand growth and insecure supply are causing price inflation of fish oil, helping to drive its substitution in aquaculture feeds by vegetable oils. This is reducing the content of n-3 LC-PUFA in aquaculture products, especially salmon, with potentially negative health implications. Given the scope for further substitution of fish oil, it is unlikely that future growth of global aquaculture will be constrained by reducing omega-3 content, although it will complicate consumer marketing of salmon. Nutraceuticals is paying more than aquaculture for fish oil based on omega-3 content, but novel sources of n-3 LC-PUFA will become available in the medium term. 相似文献
306.
Involvement of Protein cAMP‐dependent Kinase,Phospholipase A2 and Phospholipase C in Sperm Acrosome Reaction of Chinchilla lanigera 下载免费PDF全文
MC Gramajo‐Bühler L Zelarayán G Sánchez‐Toranzo 《Reproduction in domestic animals》2016,51(1):150-157
The mechanisms involved in fertilization are the centre of attention in order to determine the conditions required to reproduce in vitro the events that take place in vivo, with special interest in endangered species. Previous data from mouse sperm, where acrosome reaction (AR) occurs more often in the interstitium of the cumulus oophorus, contribute to strengthen the use of progesterone as a physiological inducer of this process. We studied the participation of protein kinase A (PKA), phospholipases A2 and C (PLA2, PLC) in the AR induced by progesterone from Chinchilla epididymal spermatozoa. The addition of db‐cAMP to the incubation medium caused an increase of 58% in the AR, while the use of H89 (30 μm ), a PKA inhibitor, reflected a decrease of 40% in the percentage of reacted gametes. The assays conducted with arachidonic acid showed a maximum increase of 23% in the AR. When gametes were pre‐incubated with PLA2 inhibitors, a dose‐dependent inhibitory effect was observed. The addition of phorbol12‐myristate13‐acetate (10 μm ) revealed higher percentages of AR induction (60%). When PLC was inhibited with neomycin and U73122, a dose‐dependent decrease in AR percentages was observed. Combined inhibition of PKA, PLA2 and PLC, AR values similar to control were obtained. This work shows evidence, for the first time in Chinchilla, that progesterone activates the AC/cAMP/PKA system as well as sperm phospholipases and that these signalling pathways participate jointly and cooperatively in AR. These results contribute to the understanding of the complex regulation that is triggered in sperm after the effect of progesterone. 相似文献