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241.
Takeshi Yamamoto Nobuhiro Suzuki Hirofumi Furuita Tsuyoshi Sugita Natsumi Tanaka Takanobu Goto 《Fisheries Science》2007,73(1):123-131
A feeding experiment was conducted to evaluate the supplemental effect of bile salts to a defatted soybean meal-based non-fish
meal diet for rainbow trout Oncorhynchus mykiss. A fish meal-based diet (FM) and two non-fish meal diets with and without bovine bile salts (SC+B and SC, respectively) were
fed to fish (13 g initial weight) for 10 weeks. Fish fed diet SC showed inferior growth and feed efficiency, while bile salt
supplementation improved the parameters to the same levels as fish fed diet FM. Crude fat and starch digestibility of diet
SC-fed fish decreased after the 10-week feeding trial compared to the data obtained with fish that had no experience of the
diet. Total biliary bile salt content and intestinal maltase activity of fish fed diet SC were the lowest among treatments,
while these parameters were improved by bile salt supplementation. Morphological changes occurred in the distal intestine
and liver of the diet SC group, although the histological features of fish fed diet SC+B were similar to those of fish fed
diet FM. These results suggest that bile salt supplementation to a soybean meal-based diet improves the nutrient utilization
by normalizing digestive processes in rainbow trout. 相似文献
242.
Chugun A Uchide T Tsurimaki C Nagasawa H Sasaki T Ueno S Takagishi K Hara Y Temma K 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2008,70(3):255-264
We reported previously that doxorubicin, an anticancer agent that has an anthracycline structure, alters Ca2+ releasing and uptake mechanisms in the sarcoplasmic reticulum of myocardial cells. These effects of doxorubicin are apparently related to its cardiotoxicity. Mitoxantrone is a similar anticancer agent with an anthracenedion structure that has been shown to be significantly less cardiotoxic. In the present study, the effects of mitoxantrone on the functions of the sarcoplasmic reticulum were examined in isolated muscle preparations obtained from the guinea-pig heart. In electrically-stimulated left atrial muscle preparations, incubation in vitro for 4 hr with 30 or 100 microM mitoxantrone significantly prolonged the time to the peak of twitch tension, markedly increased the developed tension observed at lower stimulation frequencies, thereby attenuating the slope of positive force-frequency relationships, and increased the postrest contraction observed after a 60-sec quiescent period. In myocytes isolated from ventricular muscles, 30 microM mitoxantrone increased the peak and the size of intracellular Ca2+ concentrations ([Ca2+] i), and prolonged the time to peak [Ca2+]i. In skinned muscle fiber preparations obtained from the left ventricular muscle, 30 muM mitoxantrone significantly increased the caffeine-induced contraction without affecting the Ca2+ sensitivity of contractile proteins. These results suggest that mitoxantrone enhances Ca2+ release from the sarcoplasmic reticulum in isolated atrial muscle preparations obtained from the guinea-pig heart. Apparent enhancement of the sarcoplasmic reticulum functions, in contrast to anthracyclines that has been shown to suppress these functions, seems to explain the relative lack of marked cardiotoxicity of mitoxantrone. 相似文献
243.
Nucleotide sequence analysis of VP2 hypervariable domain of infectious bursal disease virus detected in Japan from 1993 to 2004 总被引:2,自引:0,他引:2
244.
Tsuyoshi Shimmura Yuji Maruyama Saori Fujino Eriko Kamimura Katsuji Uetake Toshio Tanaka 《Animal Science Journal》2015,86(2):214-220
We reported previously that behavioral development of chicks was promoted remarkably by the presence of a broody hen. Here we report that these effects at an early age persist after maturity. A total of 60 female chicks were randomly assigned to one of two treatment groups: six pens with five chicks (brooded group) each were reared by a broody hen and six pens with five chicks (non‐brooded group) each were provided with an infrared heating lamp. We evaluated the persistent effects of broody hens by measures of behavior, physical condition and production at 9, 16, 35 and 55 weeks of age. The numbers of threatening, aggressive pecking, fighting and severe feather pecking behaviors were higher in non‐brooded than in brooded chickens (all P < 0.05). Egg production was lower in brooded than in non‐brooded chickens (P < 0.05), while the number of brooding chickens was higher in the brooded than in the non‐brooded group (P < 0.05). In conclusion, the presence of broody hens at an early stage of chicks' lives has a persistent effect on behavior. Although brooded chickens showed more brooding and lower egg production than non‐brooded chickens, feather pecking and aggressive interaction were decreased in brooded hens. 相似文献
245.
Kiwamu HANAZONO Shinya FUKUMOTO Yoshio KAWAMURA Yoshifumi ENDO Tsuyoshi KADOSAWA Hidetomo IWANO Tsuyoshi UCHIDE 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(1):1-6
Transitional cell carcinoma
(TCC), a urinary bladder tumor with high mortality, is encountered commonly in dogs.
Whereas overexpression of epidermal growth factor receptor (EGFR) is associated with
development of human urinary bladder cancer, information on EGFR expression in canine TCC
is lacking. In this study, EGFR protein and mRNA expression in canine normal bladder
(n=5), polypoid cystitis (n=5) and TCC (n=25) were examined by immunohistochemistry and
real-time polymerase chain reaction. EGFR protein expression was significantly higher in
TCC than that in normal healthy bladder (P<0.001) and polypoid
cystitis (P<0.005). High EGFR protein expression was significantly
(P<0.01) associated with TCC with a sensitivity of 72% and
specificity of 100%. Comparative analysis of protein and mRNA expression levels in TCC
showed significant positive correlation (r=0.88, P<0.05) between mRNA
and protein expression. These findings suggest that intense expression of EGFR protein
could be used as a marker to help canine TCC diagnosis. 相似文献
246.
Yoshiyuki Yanase Yoshihisa Fujii Shogo Okumura Yuji Imamura Tsuyoshi Yoshimura 《Journal of Wood Science》2000,46(3):243-247
To examine the feasibility of using plate-type waveguides for effective detection of acoustic emissions (AEs) from termite attacks in wood, AEs generated by breaking pencil leads or by termite attacks were detected using an AE sensor with a resonant frequency of 140kHz with steel plates of four different sizes and thickness and three AE sensors without them. The larger plates were associated with larger amplitudes of the artificial AEs. The amplitudes of AEs detected by an AE sensor with a steel plate larger than 30×30mm were greater than the average amplitude of the artificial AEs detected by three AE sensors. When detecting AEs generated by the feeding activity of workers,Coptotermes formosanus Shiraki, the cumulative AE events detected by the sensor with a steel plate were much larger than those of the three AE sensors without a plate. Because AE waves are attenuated much less in a steel plate than in wood, it is more effective to attach the AE sensor to wood with a steel plate rather than directly to the wood. These findings suggest that it is feasible to use an AE sensor with a plate-type waveguide for the nondestructive detection of termite attacks in wood. 相似文献
247.
248.
Lin-lin Guo Taku Nishimura Tsuyoshi Miyazaki Hiromi Imoto 《Paddy and Water Environment》2015,13(4):291-301
Agricultural management plays an important role in the storage of carbon in soils. The behavior of soil CO2 in an Andisol in two different tillage systems (no tillage and tillage) was studied. Soil-column incubation experiments were performed for a period of 150 days to conduct this study. Soil CO2 flux, under no-tillage and tillage treatments, was observed to be 0.557 and 0.616 gCO2-C m?2 d?1, respectively. The cumulative CO2 flux under tillage treatment was observed to be higher than that under no-tillage treatment, but no distinct difference in the soil carbon stock was observed between both treatments. The soil CO2 concentration under no-tillage treatment was clearly much higher than that under tillage treatment, except at a depth of 2.5 cm. Tillage decreased soil dry bulk density and enhanced soil air-filled porosity. Soil gas diffusivity, which depends on air-filled porosity, was increased by tillage at a depth of 0–15 cm, which contributed to their lower soil CO2 concentration. CO2 flux through the soil profile, calculated from the CO2 concentration, decreased with depth. Compared to the deep soils, the surface soil (0–5 cm) showed greater variation in CO2 flux. The CO2 production at depths of 0–10 cm accounted for 62.2 and 51.7 % of the whole CO2 production of the 0–30-cm soil profile for no-tillage and tillage treatments. CO2 production was higher for soil under no tillage at depths of 0–10 cm, but contrary results were observed for soil at depths of 10–30 cm. 相似文献
249.
250.
Previous reports indicated that the emission of nitrous oxide (N2O) when manure compost pellets (MCP) were applied to soil was greater than when ordinary manure compost or inorganic fertilizer was applied, but that applying pellets of nitrogen-enriched manure compost, a by-product of deodorizing manure during composting, resulted in N2O emission rates less than those from MCPs. To investigate the mechanism by which N2O emission rates and cumulative emissions were reduced in nitrogen-enriched manure composts pellets (N+MCP), we studied the impact of pellet pH on N2O emission, because pH is different between MCP (pH 8.6) and N+MCP (pH 5.3). In an incubation experiment, the pH of pellets was adjusted to five levels (5.3, 6.0, 7.0, 8.0 and 8.6) with acid or alkaline solutions, and the pellets were incubated without soil in a beaker at 30°C for 90 d (MCP) or 42 d (N+MCP). A large peak in N2O emission rate was observed soon after beginning the incubation (within 1–3 d) in the neutral and alkaline treatments for both MCP and N+MCP, and these peaks corresponded to a rise in the pellet nitrite contents. Thus, this N2O emission peak might have been generated by the denitrification of nitrite in the pellets. In the acid treatments of MCP, the N2O emission was distributed more in the later incubation period (14–90 d), when the reduction of nitrate in MCP occurred. This led to a significant increase in cumulative N2O emission as compared with the alkaline treatments for MCP. Regarding the mechanism by which N2O emission was reduced in N+MCP, although larger cumulative N2O emission rates in the earlier stage (0–14 d for MCP and 0–7 d for N+MCP) were observed when the pellet pH was adjusted close to 7.0, lowering the pH of MCP to 5.3 (the pH of N+MCP) did not demonstrate a significant decrease in cumulative N2O emission as compared with the original pH treatment (pH 8.6). These results indicate that pellet pH might not relate directly to the mechanism by which N2O emission was reduced in N+MCP. 相似文献