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211.
Sero-prevalences of canine distemper virus (CDV), feline immunodeficiency virus (FIV) and feline leukemia virus (FeLV) were evaluated in 20 captive lions in two Japanese zoos. Anti-CDV antibody was detected in 13 of 20 lions. We could pursue antibody responses against CDV in three lions back to 1996. Sera collected in 1996 were negative for anti-CDV antibody, therefore, all of them showed sero-conversion in 2000. This result suggested that the epidemic of CDV infection in this zoo might have happened between 1996 and 2000. The lions were also examined for FIV and FeLV infections. We had no evidence for FeLV infection but eight lions were sero-positive for anti-FIV antibody.  相似文献   
212.
Fisheries Science - The Silond catfish Silonia silondia, locally known as Nga Myin Yinn, is a commercially important fish in Myanmar; however, fundamental knowledge of its population structure is...  相似文献   
213.
Enzyme inhibition owing to cadmium (Cd) accumulation in the soluble high molecular weight fraction (HMF) of the liver from rainbow trout was investigated by measuring the inhibition of aminolevulinate dehydratase (ALAD). Factors affecting ALAD, which reacts specifically to metal, were examined before measuring ALAD activity. Although enzyme inhibition by Cd in the HMF was confirmed in the excretion 2 (E2) group fed Chinese parsley (CP), it was weaker than that in the excretion 1 (E1, control) group, probably due to the chelation of Cd by some substances contained in CP. Based on the absorption spectrum, the proportion of Cd bound to cysteine thiol radicals in the HMF of the E2 group was greater than that of E1. The HMF might detoxify harmful metals to some extent because it contains relatively higher levels of cysteine residues than metallothionein (MT) and shows comparatively weak enzyme inhibition. The results of the present study demonstrated that, in addition to MT, HMF is involved in the detoxification of harmful heavy metals in fish.  相似文献   
214.
The color of Undaria pinnatifida after boiling is an important factor determining its marketable value. Our previous study showed that decreased nutrients and elevated irradiance resulted in increases of lightness and yellowness (i.e., discoloration) of this alga. However, little is known about the optimal levels of nutrients and irradiance required to decrease these color values and the combined effects of these factors and boiling. We conducted two culture experiments to test the effects of nutrients (non-enriched and 1.25, 5, and 25% PESI enriched treatments), irradiance (0, 10, 30, and 180 µmol m?2 s?1), and boiling on lightness L*, redness a*, and yellowness b* of this alga. L* and b* did not differ between non-enriched and 1.25–5% PESI treatments, but were lower in the 25% PESI treatment. L* and b* were lowest at 0–10 µmol m?2 s?1, although negative growth occurred at 0 µmol m?2 s?1. Decreased irradiance had a positive or little effect on a* before boiling, but had a negative effect after boiling. These results suggest that around 25% PESI and 10 µmol m?2 s?1 were the optimal levels to decrease the three color values of this species after boiling.  相似文献   
215.
An in vitro model of acute and chronic infections with feline immunodeficiency virus (FIV) was used to examine the effect of two immunosuppressive agents, cyclosporin A (CsA) and tacrolimus (also known as FK506), on the inhibition of the replication of the virus and of apoptosis. Both drugs significantly suppressed virus production in a dose-dependent manner in acutely and chronically infected cells. The ability of FK506 to inhibit virus replication was much lower than that of CsA, and was accompanied by marked antiproliferative activity. Treatment of infected cells with either CsA or FK506 did not affect the rise of free intracellular Ca2+ but did protect the cells against apoptosis. Thus, the antiviral activity of CsA and FK506 makes these compounds promising candidates for the development of drugs suitable for the treatment of AIDS.  相似文献   
216.
217.
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   
218.
ABSTRACT:   Genetic polymorphisms were investigated to develop a simple and rapid method to differentiate between the two closely related species, Porphyra tenera and Porphyra yezoensis . Polymerase chain reaction (PCR) using the specific primer pair of the ARP4 gene gave length polymorphic single fragments of genomic DNAs from five strains of P. tenera (Japan T-8, JTW; Korea KTY1, KTY2, KTY3) and seven strains of P. yezoensis (Japan TU-1, TU-2, TUH-25, JHU, JA-1; Korea KGJ, KPH). All strains of P. yezoensis had introns 60 bp longer than that of P. tenera . Multiple cleaved amplified polymorphic sequence (CAPS) markers were also developed to differentiate P. tenera and P. yezoensis . This is the first report of length polymorphisms that can be used to differentiate between the two species using only PCR amplification with agarose gel electrophoresis. It is expected that the length polymorphism and plentiful CAPS profiles obtained in this study will be useful in the assessment of genetic diversity within P. tenera and P. yezoensis as well as in breeding science that requires the collection of various strains of the two species.  相似文献   
219.
The reproductive performance of dairy cows has declined, along with an increase in their milk yield. First-service conception rates in lactating dairy cows are often lower than 50%. The precise detection of estrus is an important factor in the reproductive management of dairy cows for successful fertilization and pregnancy. However, estrus expression has been decreasing in modern dairy cows, affecting the detection rate of estrus. In addition to estrus, a high incidence of ovulation disorders affects the fertility of dairy cows. To address these problems, it is necessary to understand the changes in the endocrine functions that underlie estrus and ovulation disorders, and to develop effective treatment strategies. Recent studies have revealed that neurokinin B and neurokinin 3 receptor signaling play important roles in the regulation of the secretion of gonadotropin-releasing and luteinizing hormones, suggesting a potential clinical avenue for the stimulation of gonadal function. In this review, I have discussed the problems in estrus and ovulation disorders in modern dairy cows as well as the possible applications of neurokinin 3 receptor agonists in the treatment of these disorders.  相似文献   
220.
A high cyclic adenosine monophosphate (cAMP) level in fully-grown immature oocytes prevents meiotic resumption. In Xenopus, inhibitory cAMP is synthesized within oocytes depending on a stimulatory alpha-subunit of G-protein (Gsalpha). In the present study, we examined whether ooplasmic Gsalpha is involved in meiotic arrest of porcine oocytes. First, we studied the presence of Gsalpha molecules in porcine oocytes by immunoblotting, and this suggested the presence of reported isoforms (45 and 48 kDa) not only in cumulus cells but also in porcine oocytes. Then we injected an anti-Gsalpha antibody into porcine immature oocytes and found that inhibition of ooplasmic Gsalpha functions significantly promoted germinal vesicle breakdown of the oocytes, whose spontaneous meiotic resumption was prevented by 3-isobutyl-l-methylxanthine (IBMX) treatment. Although cyclin B synthesis and M-phase promoting factor (MPF) activation were largely prevented until 30 h of culture in IBMX-treated oocytes, injection of anti-Gsalpha antibody into these oocytes partially recovered cyclin B synthesis and activated MPF activity at 30 h. These results suggest that meiotic resumption of porcine oocytes is prevented by ooplasmic Gsalpha, which may stimulate cAMP synthesis within porcine oocytes, and that synthesized cAMP prevents meiotic resumption of oocytes through the signaling pathways involved in MPF activation.  相似文献   
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