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51.
An 8-month-old common marmoset (Callithrix jacchus) was presented with tic-like symptoms, and a 2-year-old pigmy marmoset (Callithrix pygmaea) was presented with dyspnea and hypersalivation. Both monkeys died within a few days, and necropsies were performed. Histopathological examinations revealed ulcerative stomatitis with epithelial cell swelling and eosinophilic intranuclear inclusion bodies in the oral epithelium of both cases. In the central and peripheral nervous systems, neuronal cell degeneration with intranuclear inclusion bodies was observed. Immunohistochemical examination using anti-herpes simplex virus type 1 antibody revealed virus antigens in both cases. Both animals had been kept as pets with limited exposure to the ambient environment except via their owners. Therefore, herpes simplex virus type-1 was probably acquired from close contact with their owners.  相似文献   
52.
ABSTRACT

This study aims to characterize soil chemical properties and microbial biomass, greenhouse gas production, and organic matter dynamics in upland rice field as affected by the long-term fertilizer managements in Uganda. Soil total C (TC) and N (TN) contents were in the relatively smaller range under different fertilizer treatments, even after 20 crop seasons. However, available phosphate contents showed positive correlation with average yield of upland rice. Incubation experiments were conducted under aerobic or under flooding conditions to measure CO2, methane, and nitrous oxide productions. After the incubation, soil samples were extracted to quantify nitrification rate for aerobic condition and ammonification rate for flooding condition. Soil microbial biomass carbon (MBC) and nitrogen were measured. Stable isotope ratio of 13C and 15N were also determined for the soil samples. CO2 production potential under aerobic condition was higher than the flooding condition. The qCO2 (CO2/MBC) in the treatment applied with compost tended to be higher than the other treatments. Positive correlation between nitrous oxide production and nitrification was found. The delta 13C values of the soil samples indicated that the effect of C4 plants before rice cultivation still remained, while the contribution of biological N2 fixation was little according to delta 15N values. These results indicate that soil microbial biomass in upland rice field of the long-term fertilizer experiment in Uganda was characterized with higher qCO2. Greenhouse gas production was affected by fertilizer management, while soil organic C before the long-term experiment still remained in the experiment.  相似文献   
53.
l ‐ascorbyl‐2‐monophosphate‐Na/Ca (AMP‐Na/Ca) was used as a vitamin C source to investigate the ascorbic acid (AsA) requirements on growth performance and stress resistance of the post‐larval kuruma shrimp, Marsupenaeus japonicus. Purified carrageenan‐microbound diets with six levels of AMP‐Na/Ca, AsA equivalent to 0, 20, 56, 87, 759 and 1697 mg kg?1 diet were fed to triplicate groups of M. japonicus (mean initial weight 16±0.3 mg) for 30 days. The diets with AsA 0, 20 and 56 mg kg?1 showed high cumulative mortality after 10 days of feeding. After the 30‐day trial, the shrimp fed these diets had significantly lower survival and weight gain (WG, %) than those fed the 87, 759 and 1697 mg AsA kg?1 diets. Specific growth rate and individual dry weight showed the same pattern as WG (%). There were no significant differences in growth performance among the groups fed the AsA levels at 87, 759 and 1697 mg kg?1 at the termination of feeding trial. Broken‐line regression analysis indicated that 91.8 mg AsA kg?1 in the diet was the optimum for post‐larval shrimp. On the other hand, dietary level of more than 800 mg AsA kg?1 was needed to ensure high resistance to stressful conditions such as osmotic and formalin stressors.  相似文献   
54.
A feeding trial using five semi-purified diets (50% crude protein) was conducted to investigate the effects of different dietary amino acid patterns on growth and body composition of juvenile Japanese flounder. The control diet contained casein and gelatin as intact protein sources and four other diets contained 30% casein–gelatin (2:1, w/w) and 20% crystalline amino acids (CAA). CAA were added to the diets to simulate the amino acid pattern found in red sea bream egg protein (REP), Japanese flounder larvae whole body protein (FLP), Japanese flounder juvenile whole body protein (FJP), and brown fish meal protein (BFP), respectively. The test diets were fed to triplicate groups of juveniles (2.75±0.05 g) twice a day for 40 days to evaluate weight gain, survival, feed conversion efficiency (FCE), protein efficiency ratio (PER), and apparent protein utilization (APU). The apparent retention of total dietary amino acids in the whole body and A/E ratios of the whole body were also evaluated. The highest weight gain was observed in fish fed the diet containing the dietary amino acid pattern of BFP followed by fish fed the control, FJP, FLP and the REP diets. Percent survival, FCE, PER and APU were also significantly (P<0.05) affected by the amino acid pattern in the diets, indicating the highest value in fish fed the BFP diet. Except for a few amino acids, the amino acid composition of the whole body did not show marked differences with different dietary amino acid pattern. Results suggest that BFP could be more suitable as a reference amino acid pattern in the diet of juvenile Japanese flounder compared to the amino acid pattern of FLP, FJP or REP.  相似文献   
55.
A 55-d feeding experiment was conducted to evaluate the effects of dietary vitamin A on growth of juvenile red sea bream Chrysophrys major . Nine semi-purified diets with supplemental retinol palmitate at levels of 0, 300, 600, 1,500, 3,000, 4,500, 6,000, 15,000 and 30,000 retinol eq/kg diet, were fed twice daily to triplicate groups of 10 juveniles per tank with an initial weight of 1.178 ± 0.001 g. Weight gain and specific growth rate increased with the increase of supplemental retinol palmitate in the diet up to a level of 6,000 retinol eq/kg diet, beyond which those indices tended to decrease slightly or to plateau. Significantly lower weight gain and specific growth rate were observed in fish fed with 0 and 300 retinol eq/kg diet. No significant differences were found in survival rates among the different levels of supplementation. The crude protein, lipid, moisture and ash contents in the whole body were not affected by the different vitamin A supplemental levels. Besides the reduced growth, fish fed with low levels of vitamin A supplement showed no other signs of deficiency. No hypervitaminosis A symptoms were observed in fish fed on high levels of supplementation. Fish fed on diets with 0 and 300 retinol eq/kg diet showed a significantly lower content of vitamin A (as a total retinol) in the liver than those in groups fed with higher levels of supplementation. Vitamin A was stored in the liver mainly as retinyl esters. Total retinal content of the eye showed no significant differences among the treatments; however, fish fed with 0 and 300 retinol eq/kg of diet had slightly higher concentrations. According to the results of the mean weight gain, specific growth rate and liver retinol content, the requirement of dietary vitamin A for juvenile red sea bream was estimated to be between 1,500 and 6,000 retinol eq/kg.  相似文献   
56.
We examined the correlation between the glomerular filtration rate (GFR) estimated from an equation based on the serum iodixanol clearance technique and International Renal Interest Society (IRIS) stages of chronic kidney disease (CKD) in cats. The equation included the injection dose, sampling time, serum concentration and estimated volume of distribution (Vd) of the isotonic, nonionic, contrast medium iodixanol as a test tracer. The percent changes in the median basal GFR values calculated from the equation in CKD cats resembled those of IRIS stages 1–3. These data validate the association between the GFR derived from the simplified equation and IRIS stages based on the serum creatinine concentration in cats with CKD. They describe the GFR ranges determined using single-sample iodixanol clearance for healthy cats and cats with various IRIS stages of CKD.  相似文献   
57.
The pituitary gland is present in all vertebrates, from agnathans (jawless vertebrates) to mammals, but not in invertebrates. Reproduction in gnathostomes (jawed vertebrates) is controlled by two pituitary gonadotropins (GTHs), luteinizing hormone and follicle-stimulating hormone, which are part of the pituitary glycoprotein hormone (GPH) family. Hagfishes, which lack both jaws and vertebrae, are considered the most primitive vertebrate known, living or extinct. Accordingly, they are of particular importance in understanding the evolution of the pituitary GPHs and their functions related to vertebrate reproduction. Nevertheless, key elements of the reproductive endocrine system in hagfish have yet to be elucidated. Our current report has revealed the first identification of a functional GPH composed of two subunits that possess gonadotropic action at the pituitary of brown hagfish. It seems most likely that an ancestral GPH gave rise to only one GTH in hagfish pituitary and that multiplicity of GPHs arose later during the early evolution of gnathostomes. This paper briefly summarizes the latest findings on the hagfish GPH from an evolutionary point of view.  相似文献   
58.
59.
BACKGROUND: Dibenzoylhydrazine analogues have been developed successfully as a new group of insect growth regulators, called ecdysone agonists or moulting accelerating compounds. A notable feature is their high activity against lepidopteran insects, raising the question as to whether species‐specific analogues can be isolated. In this study, the specificity of ecdysone agonists was addressed through a comparative analysis in two important lepidopterans, the silkworm Bombyx mori L. and the cotton leafworm Spodoptera littoralis (Boisd.). RESULTS: When collections of non‐steroidal ecdysone agonists containing different mother structures (dibenzoylhydrazine, acylaminoketone, tetrahydroquinoline) were tested, in vitro reporter assays showed minor differences using cell lines derived from both species. However, when compounds with high ecdysone agonist activity were examined in toxicity assays, larvicidal activity differed considerably. Of note was the identification of three dibenzoylhydrazine analogues with > 100‐fold higher activity against Bombyx than against Spodoptera larvae. CONCLUSION: The present study demonstrated that species‐specific ecdysone‐agonist‐based insecticides can be developed, but their species specificity is not based on differences in the activation of the ecdysone receptor but rather on unidentified in vivo parameters such as permeability of the cuticle, uptake/excretion by the gut or metabolic detoxification. Copyright © 2010 Society of Chemical Industry  相似文献   
60.
Sclerotinia sclerotiorum (Lib.) de Bary is a phytopathogenic fungus capable of causing significant yield losses in numerous crops, including canola, in which the fungus causes sclerotinia stem rot. Immunological detection methods to rapidly determine the presence of S. sclerotiorum on plants may provide growers with a viable diagnostic tool to aid with fungicide use decisions. This paper discusses the generation of a monomeric and dimeric single-chain, variable fragment (scFv) antibody with affinity for S. sclerotiorum using phage display technology. The bacterially expressed and purified scFv is shown to bind S. sclerotiorum with some cross-reactivity with the closely related phytopathogen Botrytis cinerea (Pers.:Fr.). The dimeric scFv displayed improved binding to the fungus as compared to the monomer and could detect the presence of mycelia in inoculated canola petals. To the authors' knowledge, this is the first report of a scFv dimer with affinity for S. sclerotiorum that has the potential for use in the development of a new diagnostic test.  相似文献   
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