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191.
The main flavonoids were isolated from three selected onion cultivars. Three phenolic compounds were obtained by reverse-phase HPLC, and their structures were elucidated by multiple NMR measurements. There were two known compounds, quercetin and quercetin 3'-O-β-D-glucopyranoside (Q3'G), and one novel compound, quercetin 3-O-β-D-glucopyranoside-(4→1)-β-d-glucopyranoside (Q3M), which was identified in onion for the first time. These flavonoids were found to be more abundant in the onion peel than in the flesh or core. Their antioxidative activities were tested using the DPPH method, and their antiaging activities were evaluated using a Caenorhabditis elegans lifespan assay. No direct correlation was found between antioxidative activity and antiaging activity. Quercetin showed the highest antioxidative activity, whereas Q3M showed the strongest antiaging activity among these flavonoids, which might be related to its high hydrophilicity.  相似文献   
192.
To detect the predominant lactobacilli in the intestinal flora of healthy thoroughbreds, we isolated lactobacilli from the feces of nine thoroughbreds (five males and four females; 0–15-year-old). The isolated lactobacilli comprise 17 species (37 strains), and they were classified into five groups: Lactobacillus salivarius (6 species), L. reuteri (6 species), Lactobacillus delbrueckii (3 species), L. buchneri (1 species) and L. vitulinus (1 species). On the basis of 16S rRNA gene sequences, we identified 3 other phylogenetic relatives belonging to the genus Lactobacillus . These results suggest that the intestinal flora of thoroughbreds may comprise many species of the genus Lactobacillus . Polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) analyses of the 340-bp fragments of the 16S rRNA genes from the same nine fecal samples showed that L. hayakitensis , L. equigenerosi and L. equi are contained in all the samples, suggesting that these species are predominant lactobacilli in the intestinal flora of thoroughbreds.  相似文献   
193.
Cushing's disease caused by pituitary corticotroph adenoma in dogs is usually treated by medical treatment, and the efficacy of this treatment has been reported. However, controversy remains as to whether reduced negative feedback through the inhibition of cortisol secretion, similar to Nelson's syndrome, may appear as an adverse effect. The purpose of this study was to investigate the effect of reduced negative feedback through the inhibition of cortisol secretion by daily trilostane administration on the pituitary–adrenal axis in clinically normal dogs. Dogs were administered 5 mg/kg trilostane twice a day every day for 8 weeks (n = 8) or 16 weeks (n = 3). After the initiation of trilostane administration, plasma adrenocorticotropic hormone (ACTH) concentrations were increased remarkably. As assessed by magnetic resonance imaging (MRI) during administration, the pituitary became enlarged. After trilostane administration, the cytoplasmic areas of the pituitary corticotrophs were increased and the ratio of pituitary corticotrophs to all cells in the anterior lobe was greater in the trilostane-treated dogs than that in untreated animals. In addition, histological examinations revealed bilateral adrenal cortical hyperplasia. Using real-time PCR quantification, the expression of proopiomelanocortin (POMC) mRNA in the pituitary and ACTH receptor (ACTH-R) mRNA in the adrenal gland was greater in the dogs treated with trilostane than in untreated dogs. These results indicate that reduced negative feedback induced hyperfunction of the pituitary corticotrophs and pituitary enlargement in healthy dogs. These changes suggest that the inhibition of cortisol secretion by trilostane may increase the risk for accelerating the growth of corticotroph adenomas in dogs with Cushing's disease.  相似文献   
194.
In poorly drained fields, tube drains are used to improve drainage. In some cases, however, there are fields where the effects of tube drainage have deteriorated within several years after installation. One cause of malfunction is low permeability of backfilled soils (Ishiwata et al. 1990, 1992, 1993). Another cause is clogging of tubes by deposits (Trafford et al. 1973; Dent 1986; Koutani et al. 1989; Kusaka et al. 1993; Kaneko et al. 1995).  相似文献   
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196.

Background

The aim of our study was to investigate the possible etiology of avian colibacillosis by examining Escherichia coli isolates from fecal samples of healthy broilers.

Findings

Seventy-eight E. coli isolates from fecal samples of healthy broilers in Japan were subjected to analysis of phylogenetic background, virulence-associated gene profiling, multi-locus sequence typing (MLST), and antimicrobial resistance profiling. Phylogenetic analysis demonstrated that 35 of the 78 isolates belonged to group A, 28 to group B1, one to group B2, and 14 to group D. Virulence-associated genes iutA, iss, cvaC, tsh, iroN, ompT, and hlyF were found in 23 isolates (29.5%), 16 isolates (20.5%), nine isolates (11.5%), five isolates (6.4%), 19 isolates (24.4%), 23 isolates (29.5%), and 22 isolates (28.2%) respectively. Although the genetic diversity of group D isolates was revealed by MLST, the group D isolates harbored iutA (10 isolates, 71.4%), iss (6 isolates, 42.9%), cvaC (5 isolates, 35.7%), tsh (3 isolates, 21.4%), hlyF (9 isolates, 64.3%), iroN (7 isolates, 50.0%), and ompT (9 isolates, 64.3%).

Conclusions

Our results indicated that E. coli isolates inhabiting the intestines of healthy broilers pose a potential risk of causing avian colibacillosis.  相似文献   
197.
ABSTRACT:   Microstructures of sagittae and lapilli were examined in relation to somatic growth for reared larvae and juveniles of Pacific cod. The Laird–Gompertz model was fitted to the daily age and somatic growth relationship. Growth increments were deposited on a daily basis in both kinds of otoliths, with a check formed at hatching. Two subsequent checks and an accessory primordia (AP) occurred in the sagittae. The lapillus was adequate for increment width measurement through the early life stages. Sagittal and frontal plane of sagitta was adequate for measurement in the pre-AP and post-AP formation stages, respectively. The shift of desirable plane was caused by changes in otolith and increment shapes with AP formation. Back-calculated total lengths using the biological intercept method did not significantly differ with certain body lengths ( P  > 0.05), suggesting validity of back-calculation in this species. Using the back-calculated total length, morphological and ecologic changes that seemed to affect checks and AP formations are discussed.  相似文献   
198.
The effects of larval density, rearing media, and protein additions on fish larval survival were tested by rearing larvae in small containers. Yolk-sac larvae of Japanese flounder, Paralichthys olivaceus, were transferred 1 day after hatching to plastic dishes and cell-culture microplates by Pasture pipette at densities ranging from 0.3 to 30 individuals/ml and incubated at 16 °C without food. Dead larvae were removed and counted every 12 h. Three peaks of larval mortality were observed: the first peak appeared just after the transfer, the second corresponded to the completion of yolk absorption, and the third occurred 10–12 days after the transfer. Since about 50% of larvae survived until the third peak, it was clear that mortality at the second peak (completion of yolk absorption; equivalent to the first feeding) was not due to starvation. At the first mortality peak, better survival was unexpectedly recorded at higher larval densities (30 individuals/ml), suggesting that some material beneficial for survival is derived from the larvae. This idea was further supported by the improved survival in media previously used to rear larvae at high densities. The addition of bovine serum albumin (BSA) at 10 μg/ml effectively reduced mortality in microplates and in 30-l tanks. To reduce the larval mortality just after handling, addition of egg white at a dilution rate of 1/30,000 (vol/vol) or less is recommended as a practical alternative to BSA. Since the addition of polyethylene glycol 6000 (1 μg/ml) also effectively reduced mortality, reduction in mortality could not be attributed to a specific mechanism. The precise determination of the magnitude and timing of larval mortality was attained through the use of small containers, and a method to prevent mortality due to handling was identified in this study. These types of tests may allow the logical evaluation and establishment of better rearing procedures for seed production in aquaculture.  相似文献   
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200.
In this study, we performed NMR-based metabolic profiling of major rice wines (Japanese sake, Chinese Shaoxing wine, and Korean makgeolli). In the (1)H NMR spectra, the rice wines showed broad resonances in the region of about 7.9-9.0 ppm. These resonances showed many and complex correlations with approximately 0.5-4.5 ppm in the F(2)-selective TOCSY (total correlation spectroscopy) spectra, and these correlations were attributed mainly to peptides. These spectral patterns were characteristic of individual rice wines, and the combination of F(2)-selective TOCSY spectra and principal component analysis enabled us to classify the rice wine species. Furthermore, it also provided information about raw materials, namely, what type of koji (rice koji or wheat koji) was used. These spectra may be useful as a new "fingerprint" for quality control or food authentication.  相似文献   
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