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31.
In order to determine the role of the cecum on energy use in growing chickens, metabolizability of the dietary energy and energy expenditure were examined in the week following bilateral ligation and washing out of the cecum. Apparent metabolizable energy (AME) values were 14.30 and 13.69 kJ/g air‐dry matter for sham‐operated and cecally ligated chickens, respectively. These values were found to be significantly different (P < 0.05). Although AME intake and fasting heat production were decreased by cecal ligation, the distribution of AME (measured as fasting and feeding heat production, as well as heat increment and energy retention, as a proportion of AME intake) was not affected. These results suggest that the cecum helps chickens extract AME from corn‐soybean type diets with little, if any, effect on AME use, based on the present study of growing chickens in the week following cecal ligation.  相似文献   
32.
Green tea, one of the most popular beverages consumed in Asian countries, has been reported to possess anticarcinogenic and antimutagenic properties. The aim in this study is to test the radical scavenging effect of catechins and caffeine, which were major components of green tea, and if they really prevent oxygen radical-induced mutagenesis. We used TA102 strain of Salmonella typhimurium which is sensitive to hydroxyl radical in the Ames mutation assay. We found that caffeine did not show any effects on mutagenesis in this system, but catechin significantly reduced mutagenesis or genotoxicity caused by hydroxyl radical. This radical-scavenging action of catechins may indeed contribute to the anticarcinogenic activity of green tea as has been proposed.  相似文献   
33.
Japanese oak and Japanese beech were sanded by hand with abrasive papers of varying grit number. Two three-dimensional parameters selected to characterize their surface roughness – one parameter for the distribution of roughness-profile peaks and the other for the relative area of the roughness-profile peaks above the threshold height – were compared against tactile roughness. The parameters were obtained from roughness profiles as determined by a robust Gaussian regression filter (RGRF) using seven cutoffs. The RGRF filtering process was adjusted specifically for the evaluation of wood surface roughness. Except for a cutoff wavelength of 0.25mm, the RGRF lent itself well to the determination of roughness profiles. No distortion of roughness profiles occurred around deep valleys, and there was a good correlation between the parameters and tactile roughness.Part of this study was presented at the 2002 Kansai Branch Office lecture meeting of the Japan Society for Precision Engineering, Kyotanabe, August 2002  相似文献   
34.
Occupational exposure to nickel oxide (NiO) is an important cause of respiratory tract cancer. Toxicity is known to be associated with the dissociated component, i.e. nickel (II) ions. To address the relationship between physicochemical properties, including solubility in artificial lysosomal fluid, of NiO and time-course changes in the pulmonary response, we conducted an intratracheal instillation study in male Fischer rats using four different well-characterized NiO products, US3352 (NiO A), NovaWireNi01 (NiO B), I small particle (NiO C), and 637130 (NiO D). The NiOs were suspended in purified water and instilled once intratracheally into male F344 rats (12 weeks old) at 0 (vehicle control), 0.67, 2, and 6 mg/kg body weight. The animals were euthanized on days 3, 28, or 91 after instillation, and blood analysis, bronchoalveolar lavage fluid (BALF) testing, and histopathological examination were performed. The most soluble product, NiO B, caused the most severe systemic toxicity, leading to a high mortality rate, but the response was transient and surviving animals recovered. The second-most-soluble material, NiO D, and the third, NiO A, caused evident pulmonary inflammation, and the responses persisted for at least 91 days with collagen proliferation. In contrast, NiO C induced barely detectable inflammation in the BALF examination, and no marked changes were noted on histopathology. These results indicate that the early phase toxic potential of NiO products, but not the persistence of pulmonary inflammation, is associated with their solubility.  相似文献   
35.
In this study, two following experiments were performed to improve post-thaw motility and viability of frozen-thawed ram spermatozoa. We examined i) the effects of different concentrations of bovine serum albumin (0, 0.3, 1, 5, 10 and 15% BSA) in semen diluents lacking egg yolk and ii) the effects of four semen diluents, fructose (F: control) and trehalose (T) in semen diluents containing egg yolk, 15% BSA in semen diluents without egg yolk (BSA), and modified phosphate buffered saline (m-PBS). Frozen-thawed spermatozoa were examined for progressive sperm motility, viability, morphological abnormality, sperm tail swelling test, and sperm acrosome integrity. In Experiment 1, the rates of sperm motility immediately after thawing (0 h) were significantly (P<0.05) higher in the 10 and 15% BSA groups (55.0 +/- 2.9 and 58.3 +/- 6.7%, respectively) than in the positive control (F) group (41.7 +/- 4.4%). The rate of sperm viability in the negative control (0% BSA) group (80.2 +/- 3.3%) was significantly (P<0.05) lower than in the positive control (F) group (89.8 +/- 1.5%), but when compared with the F group, no significant differences were found among the 0.3, 1, 5, 10 and 15% BSA groups at 0 h. The rates of sperm morphological abnormality of the 10 and 15% BSA groups (6.5 +/- 1.3 and 6.3 +/- 1.1%, respectively) were significantly (P<0.05) lower at 0 h than that in the 1% BSA group (16.3 +/- 5.2%). In Experiment 2, T addition improved (P<0.05) the post-thaw motility compared with the F and BSA groups. Furthermore, at 3 and 6 h, the post-thaw motility of the T group (36.3 +/- 2.4 and 25.0 +/- 2.0%, respectively) was significantly (P<0.05) higher than in the BSA (26.3 +/- 2.4 and 18.8 +/- 1.3%, respectively) and F (28.8 +/- 3.8 and 18.8 +/- 2.4%, respectively) groups. The post-thaw sperm motility and viability in the m-PBS group were significantly (P<0.05) lower than those of the control (F), T, and BSA groups throughout all observation points. These results indicate that 10 and 15% BSA can be substituted for egg-yolk for ram semen diluent and that the addition of trehalose enhances motility and viability of ram spermatozoa after freezing and thawing.  相似文献   
36.
The market for wood-fiber plastic composites (WPCs) is expanding rapidly in many countries including Japan, where WPCs are mainly used for exterior products. In such applications, WPCs undergo undesirable color change, chalking, and shrinkage and swelling, and accordingly there is a need to better understand the mechanisms responsible for the weathering of WPC and develop methods of improving their weathering resistance. In this study, weatherability of WPC was assessed by natural and accelerated weathering trials. Discoloration (whitening) of WPC during exposure was caused by degradation of both wood and plastic. Darker color pigments as additives improved the color stability of WPC; however, chalking on the surfaces still occurred. The color stability of WPC was improved by application of exterior coatings. Preweathering of WPC (before coatings were applied) increased the absorption of coatings by the WPC and had a positive effect on the color stability and prevented chalking of the composites. Parts of this study were presented at the IUFRO XXII World Congress Meeting, Brisbane, August 2005 and the IAWPS 2005, Yokohama, November 2005  相似文献   
37.
G protein-coupled receptor (GPR) 120 is an unsaturated fatty acid receptor, which is associated with various physiological functions. It is reported that the genetic variant of GPR120, p.Arg270His, is detected more in obese people, and this genetic variation functionally relates to obesity in humans. Obesity is a common nutritional disorder also in dogs, but the genetic factors have not ever been identified in dogs. In this study, we investigated the molecular structure of canine GPR120 and searched for candidate genetic variants which may relate to obesity in dogs. Canine GPR120 was highly homologous to those of other species, and seven transmembrane domains and two N-glycosylation sites were conserved. GPR120 mRNA was expressed in lung, jejunum, ileum, colon, hypothalamus, hippocampus, spinal cord, bone marrow, dermis and white adipose tissues in dogs, as those in mice and humans. Genetic variants of GPR120 were explored in client-owned 141 dogs, resulting in that 5 synonymous and 4 non-synonymous variants were found. The variant c.595C>A (p.Pro199Thr) was found in 40 dogs, and the gene frequency was significantly higher in dogs with higher body condition scores, i.e. 0.320 in BCS4–5 dogs, 0.175 in BCS3 dogs and 0.000 in BCS2 dogs. We conclude that c.595C>A (p.Pro199Thr) is a candidate variant relating to obesity, which may be helpful for nutritional management of dogs.  相似文献   
38.
Fetal bovine serum (FBS) has been widely used as a supplement in the maturation medium of bovine oocytes in vitro. However, serum contains many undefined factors and is potentially infectious to humans and animals. As a serum replacement, we evaluated the feasibility of using the silk protein, sericin, derived from the cocoons of silkworm. To examine the rates of oocyte maturation and fertilization, cumulus-oocyte complexes were cultured in TCM-199 supplemented with 0.01%, 0.05%, 0.1% or 0.15% sericin or 5% FBS. The sizes of the perivitelline space that might relate to polyspermy, the expressions of Has2 and CD44 mRNA, the amount of hyaluronan (hyaluronic acid: HA) contained in the oocytes and the rates of blastocyst formation following insemination were then compared between the oocytes cultured with 0.05% sericin and 5% FBS, because the polyspermy rates in oocytes cultured with 0.05% sericin were significantly lower than in those cultured with 5% FBS. After in vitro maturation (IVM), the mean size of the perivitelline space was significantly greater in oocytes cultured with sericin than in those cultured with FBS, although the rates of nuclear maturation, fertilization and blastocyst formation of oocytes under both IVM conditions were not significantly different. The expression of HAS2 and CD44 mRNA and the amount of HA in the denuded oocytes cultured with 0.05% sericin were significantly greater than in those cultured with FBS. These results indicate the feasibility of sericin as an alternative protein supplement for IVM in bovine oocytes.  相似文献   
39.
The understanding of animal products and dairy farming is important for the promotion of dairy farming. Thus, to examine the effects of farm experience on the understanding of animal products and the management of dairy farming, the interaction between students and dairy cows was investigated in groups of first‐year veterinary nursing students in 2011 and 2012 (n = 201). These students included 181 women and 20 men. Nine items about dairy cows were presented in a questionnaire. The survey was performed before and after praxis on the educational farm attached to the authors' university. After praxis on the farm, increases occurred in the number of positive responses to the items involving the price of milk, dairy farming and the taste of milk. For these items, a significant difference (P < 0.05) was found between the scores obtained before and after training. The results of the study suggested that farm experience is useful for improving the understanding of animal products and dairy farming.  相似文献   
40.
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