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61.
With the eventual goal of making zonisamide (ZNS), a relatively new antiepileptic drug, available for the treatment of epilepsy in cats, the pharmacokinetics after a single oral administration at 10mg/kg and the toxicity after 9-week daily administration of 20mg/kg/day of ZNS were studied in healthy cats. Pharmacokinetic parameters obtained with a single administration of ZNS at 10mg/day were as follows: Cmax=13.1microg/ml; Tmax=4.0h; T(1/2)=33.0h; areas under the curves (AUCs)=720.3microg/mlh (values represent the medians). The study with daily administrations revealed that the toxicity of ZNS was comparatively low in cats, suggesting that it may be an available drug for cats. However, half of the cats that were administered 20mg/kg/day daily showed adverse reactions such as anorexia, diarrhoea, vomiting, somnolence and locomotor ataxia.  相似文献   
62.
Heterogeneity of variance among subclasses of an effect is a potential source of bias in genetic evaluation. Degrees of the heterogeneity of variance among farm‐market‐year‐sex (FMYS) subclasses for carcass weight, beef marbling standard number, rib‐eye area, rib thickness and subcutaneous fat thickness were investigated in Japanese Black cattle. Consequences of adjusting for the heterogeneity on the predicted breeding values (PBVs) or on the genetic indexes derived from the PBVs of the five carcass traits were assessed. A total of 57 461 records were collected between 1997 and 2002 from steers and heifers fattened at farms across Japan. These records were grouped into 1591 FMYS subclasses. Bartlett's test showed that the degree of the heterogeneity of variance among the FMYS subclasses was sizeable in all traits (P < 0.0001). By applying a two‐step adjustment procedure it was possible to reduce the standard deviation, the coefficient of variation and the Gini coefficient of the phenotypic variances by 67.5% to 75.0% in the different traits. The applied adjustment caused a substantial re‐ranking of elite dams in the PBV for each trait as well as in the genetic index. This study provided evidence that the applied adjustment reduces the bias in the PBVs due to heterogeneous variances and increases the accuracy of bull‐dam selection.  相似文献   
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64.
To identify mechanisms of starch degradation in rice leaf sheaths at the post-heading stage, we investigated the function of OsBAM2 and OsBAM3, which encode plastid-targeted active β-amylase isoforms, in starch remobilization in leaf sheaths. The starch content in the second leaf sheaths below the flag leaf (the third leaf sheaths) peaked at the flag leaf emergence stage and gradually decreased until 15 days after heading. The mRNA levels of OsBAM2 and OsBAM3 in the third leaf sheaths increased from the flag leaf emergence stage to the heading stage when the starch content began to decrease. However, these mRNA levels did not always remain high during post-heading. Overexpression of OsBAM2 or OsBAM3 markedly repressed starch accumulation in the third leaf sheaths, showing that OsBAM2 and OsBAM3 function in starch degradation in rice leaf sheaths. In contrast, no significant differences in starch content in the third leaf sheaths were detected between knockdown plants of OsBAM2 or OsBAM3 and non-transgenic wild-type plants. Our results suggest that reduced expression of the individual genes, OsBAM2 or OsBAM3, does not result in excess accumulation of starch in the leaf sheaths, probably because of the complementary function of another gene or the action of other genes encoding starch-degrading .  相似文献   
65.
66.
To provide experimental evidence that somatic homologous recombination (HR) is involved in the instability and diversification of the avirulence gene Avr-Pita in Pyricularia oryzae, we generated a dysfunctional Avr-Pita homolog and integrated it into strain Hoku-1 containing Avr-Pita. In the transformants, the occurrence of somatic HR events between Avr-Pita and the dysfunctional homolog was confirmed by PCR–RFLP. Germlings from conidia from the HR-positive transformants had lost the avirulence function, which enabled it to infect rice cultivar Yashiromochi containing the corresponding resistant gene Pi-ta. These results suggested that genetic mutation caused by somatic HR is one of the mechanisms responsible for virulence diversity.  相似文献   
67.
The purpose of the present study was to evaluate the capability of near infrared spectroscopy (NIRS) as a simple method to monitor the lipid content of garbage compost, which is a potential inhibitor of plant growth. We conducted a cultivation experiment with vegetable mock pak choy ( Brassica rapa L. Parachinensis Group) using two application rates of four garbage composts that differed in lipid content. The input of lipid from the compost to the field showed a significant negative correlation with germination rate and plant height in the initial growth stage. Reflectance spectra of untreated and freeze-dried and milled compost samples were taken using a scanning monochromator. Second-derivative spectra and multiple regression analysis were used to develop calibration equations for lipid and moisture contents. The calibration was carried out with the short wavelength region ([SWR] 800–1100 nm) and the long wavelength region ([LWR] 1100–2500 nm) separately. The calibration equations with the LWR were more accurate than those with the SWR for lipid and moisture determinations. The accuracies of the calibration equations for untreated samples were comparable to those for freeze-dried and milled samples. In conclusion, we suggest that the application rate of garbage compost can be determined by measuring the lipid content of untreated samples by NIRS.  相似文献   
68.

Background  

Morus boninensis, is an endemic plant of the Bonin (Ogasawara) Islands of Japan and is categorized as "critically endangered" in the Japanese red data book. However, little information is available about its ecological, evolutionary and genetic status, despite the urgent need for guidelines for the conservation of the species. Therefore, we adopted Moritz's MU concept, based on the species' current genetic structure, to define management units and to select mother tree candidates for seed orchards.  相似文献   
69.
A new method based on scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM–EDX) was developed for visualizing the distribution of cesium ions (Cs+) adsorbed by Japanese cedar charcoal. After being soaked in saturated aqueous CsCl solutions, wood charcoal and regular wood samples were embedded in resin, and thin sections of sample were prepared for the Cs+ observations. The Cs+ ions on charcoal could be seen in EDX mapping images and also in line profiles with enough contrast to identify differences between the various carbonized cell wall regions. On the other hand, Cs+ could not be observed in the EDX mapping images of wood samples, despite having been soaked in a saturated aqueous CsCl solution. These results indicate that Cs+ adsorbed on charcoal can be visualized using this method, but not Cs+ in wood. Additionally, oxygen detected on the charcoal by EDX can be regarded as an indicator of the presence of surface functional groups.  相似文献   
70.
The primary objective of this study was to characterize Fusarium spp. associated with the economically devastating mango malformation disease (MMD) in Mexico. In all, 142 Fusarium strains were isolated from symptomatic mango inflorescences and vegetative tissues in eight geographically diverse Mexican states from 2002 through 2007. Initially, all the Mexican isolates were screened for genetic diversity using appolymerase chain reaction and random amplified polymorphic DNA markers and were grouped into seven distinct genotypes. Based on results of these analyses, evolutionary relationships and species limits of the genetically diverse MMD-associated Fusarium spp. were investigated using multilocus DNA sequence data and phylogenetic species recognition. Maximum parsimony analyses of a five-locus data set comprising 5.8 kb of aligned DNA sequence data indicated that at least nine phylogenetically distinct Fusarium spp. within the Gibberella fujikuroi species complex are associated with MMD, including one species within the African clade (Fusarium pseudocircinatum), two species within the Asian clade (F. mangiferae and F. proliferatum), and at least six species within the American clade (F. sterilihyphosum and five undescribed Fusarium spp.). Molecular phylogenetic analyses indicate that a novel genealogically exclusive lineage within the American clade was the predominant MMD associate in Mexico. This new Fusarium sp. caused MMD and could be distinguished from all other known species morphologically by the production of mostly sterile, coiled hyphae which are typically associated with sporodochial conidiophores together with unbranched or sparsely branched aerial conidiophores. Koch's postulates were completed for isolates of the new species on nucellar seedlings of mango cv. Ataulfo. This pathogen is formally described herein as F. mexicanum.  相似文献   
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