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1.
Keratometry was performed in 73 domestic cats of varied signalment in Japan using an automated handheld keratometer. The mean corneal curvature radius was significantly lower for cats younger than 1 year than for those older than 2 years (8.04 mm vs. 8.80−8.99 mm, P<0.01). The radius was significantly greater in males than in females among the cats older than 11 years (9.22 mm vs. 8.84 mm, P=0.01), while the age distributions of the males and females were similar. Corneal astigmatism did not significantly differ across the gender and age groups. The predictability of the corneal curvature and astigmatism was approximately 41−43% and less than 3%, respectively, as a function of age and bodyweight. The results highlighted some age- and sex-related keratometric variations in domestic cats in Japan.  相似文献   
2.
Among the reported probiotic Bacillus strains, B. subtilis C-3102 has the unique potential to improve feed uptake under stress conditions in the broilers, piglets, and cows. In this study, we sought to evaluate the protective effect of feed additive probiotic Bacillus subtilis C-3102 against Salmonella enterica infection of specific pathogen-free (SPF) chicks in floor pens in two experiments. In the experiment-1, the chicks in the control group (n=32) were fed a basal diet and those in the C-3102 group (n=32) were fed a basal diet supplemented with 1×106 CFU/g of feed for 28 days. On day 7 post-challenge with S. enterica, there was no significant change in the body weight between both the groups throughout the test period, whereas detection rates of S. enterica in the C-3102 group were significantly lower in the cecum and liver on days 21 and 14 post-challenge, respectively. In the experiment-2, minimum dosage of C-3102 cells required to protect Salmonella infection was evaluated using 3 dosages. Chicks were divided into four groups, fed with different dosages of C-3102 (1×106, 5×105, 3×105, and 0 CFU/g of feed), and challenged with S. enterica (2.8×108 CFU/chicken). S. enterica infection was completed within 7 days post- challenge and was almost excluded from the liver and spleen on day 21 post- challenge in the control group. Average values showed a trend for higher infection rates in the control group >3×105>5×105>1×106 CFU/g on days 14 and 21 post-challenge. These results suggest that B. subtilis C-3102 supplementation has the potential to reduce S. enterica infection rates and/or to accelerate the exclusion of S. enterica from the chicks.  相似文献   
3.
The physicochemical properties of shark type I collagen gel and membrane were not same as those of pig type I collagen. The denaturation temperature of shark collagen gel was about 15 degrees C lower. According to scanning electronic micrography, the diameter of shark collagen fibril was relatively thin and more homogeneous. The breaking strength of shark collagen gel was greater, and shark collagen membrane had a greater mechanical strength and a higher water vapor sorption.  相似文献   
4.
Fibril reconstruction process, that is, the nucleation and growth of mixed type I collagen fibril of shark and pig, progressed faster than that of the individual collagen species of shark or pig. The reconstructed mixed collagen fibril had a greater resistance to return to the solution or to melt into gelatin in comparison with the counterpart consisting solely of shark collagen. The denaturation temperature of the mixed collagen gel was about 10 degrees C higher than that of shark, and about 5 degrees C lower than that of pig. By scanning electron microscopy, the diameter of mixed collagen fibril showed an intermediate range between shark and pig collagen fibril. The breaking strength of the mixed collagen gel was tougher than that of pig, but weaker than that of shark. Other physicochemical properties of the mixed type I collagen gel were observed to be at intermediate positions between those of shark and pig type I collagen gels.  相似文献   
5.
The effects of 3, 3', 4, 4', 5-pentachlorobiphenyl (PCB-126), which is the most toxic congener of coplanar polychlorinated biphenyls (Co-PCBs), on intracellular accumulation and transepithelial transport of vinblastine were examined in porcine kidney cells, LLC-PK1, and its transformant cells expressing human P-glycoprotein (LLC-MDR1). The accumulation decreased less than one-tenth in LLC-MDR1 compared to LLC-PK1. In both cells, the accumulation increased with the addition of PCB-126 and cyclosporine A (CYA), which are P-glycoprotein modulators, though the magnitudes were different in these two cell groups as well as for these two chemicals. Thus, PCB-126 might inhibit extrusion of vinblastine through the drug extrusion system as does CYA. In both the cells, there might be an endogenous drug extrusion system other than P-glycoprotein that was inhibited by CYA or PCB-126. The net basal-to-apical transepithelial transport of vinblastine increased 1.7-fold more in LLC-MDR1 than in LLC-PK1. By adding PCB-126 on the apical side, the transport was greatly decreased by -76% in the monolayer of both cells. By adding PCB-126 and CYA on the basal side in LLC-MDR1 monolayer, the transports increased -1.7-fold, so that PCB-126 might inhibit the extrusion of vinblastine on both the apical and basal sides. One of the causes to be considered for the adverse effects of Co-PCBs, in addition to the binding with an aryl hydrocarbon receptor, might be the modification of drug transport by its interaction with the drug transport system.  相似文献   
6.
Origin of Weedy Rice Grown in Bhutan and the Force of Genetic Diversity   总被引:9,自引:0,他引:9  
In Bhutan, weedy rice (Oryza sativa L.) was grown together with cultivated rice on terraced paddy fields lower than 2620 m above sea level. Seeds of cultivars and weedy strains were collected at 22 collection sites located from 1000 to 2620 m above sea level. Cultivars with round seeds were frequently found in fields higher than 2250 m, and those with slender seeds in fields lower than 1630 m. All cultivars and weedy strains were divided into indica or japonica types by isozyme (multi-locus) and morpho-physiological (multicharacter) analyses. Japonica cultivars predominated in highland; Indica cultivars predominated in lowland. Plastid type was confirmed by the length polymorphism for the ORF100 region. The japonica cultivars carried non-deletion type ORF100. The indica cultivars carried deletion type ORF100. In contrast, weedy strains showed discrepancy in the combination of the nuclear and cytoplasm types. An intermediate type was found in weedy strains for isozyme genotypes. A recombinant type, which has indica genotypes for isozyme analysis with japonica cytoplasm, and vice versa, was frequently found in weedy strains. These findings suggested that weedy strains would be generated by natural hybridization between indica and japonica. Further, they might fail to recombine their prior genotypes sets for isozyme and cytoplasm. Morphophysiological characters did not show such a tendency. Morpho-physiological analysis of highland plants, in particular, showed indica cultivars and weedy strains with japonica cytoplasm. Hypervariable nuclear microsatellite analysis was then used to compare cultivars and weedy strains. Identical alleles were shared between indica and japonica, and also between cultivars and weedy strains. This suggested that there was gene-flow resulting from natural hybridization.  相似文献   
7.
Twelve polar cardenolide monoglycosides, 1, 2, 4?C13, and oleagenin (3) were isolated from the methanol extract of stems and twigs of Nerium oleander. Among these, oleagenin (3) and cardenolide monoglycosides named cardenolide B-1 (1) and cardenolide B-2 (2) were isolated from natural sources for the first time. The in vitro antiinflammatory activity of compounds 1?C13 was examined on the basis of inhibitory activity against the induction of the intercellular adhesion molecule-1 (ICAM-1). Compounds 4?C7 were active at an IC50 value of less than 0.4 ??M. The cytotoxic activity of compounds 1?C13 was evaluated against three human cell lines: normal human fibroblast cells (WI-38), malignant tumor cells derived from WI-38 (VA-13), and human liver tumor cells (HepG2). Compounds 4, 6, and 7 were active toward these three cell lines at IC50 values of less than 0.7 ??M, and compounds 5 and 8 were active toward the cell lines at IC50 values of less than 1.5 ??M. The multidrug resistance (MDR) cancer-reversal activity of compounds 1?C13 was evaluated on the basis of the amount of calcein accumulated in MDR human ovarian cancer 2780AD cells in the presence of each compound. Compound 1 and 12 showed significant effects on calcein accumulation.  相似文献   
8.
9.
A series of aurones were prepared from various phenols via phenoxy acetic acids and coumaranones and evaluated for insect antifeedant activity against the common cutworm (Spodoptera litura). The naturally occurring aurone was most active at an ED50 of 0.12 micromol/cm2. The synthetic precursor, coumaranones, showed that the introduction of methoxyl and methyl groups to the benzene ring increased insect antifeedant activity. Similarly, the tested aurones showed that the introduction of methoxyl group to the A and/or B rings increased the insect antifeedant activity, but 4,5,6- and 3',4',5'-trisubstituted compounds did not show this activity in this test. The hydroxylation of aurones in the B ring should be disadvantageous for insect antifeedant activity against S. litura. Although the melting points did not correlate well with the insect antifeedant activity, compounds that were nearly inactive had high melting points. A significant correlation was noted between biological activity (pED50) and a hydrogen-bonding parameter calculated from the Rf value obtained from SiOH thin-layer chromatography and a lipophilicity parameter (log k) calculated from the retention time in ODS high-performance liquid chromatography. The respective correlation coefficients (r) were -0.83 and -0.70. The introduction of alkoxy and alkyl groups along with adequate hydrogen bonding seems to contribute to the antifeedant activity of the compounds tested.  相似文献   
10.
Porcine circovirus type 2 (PCV2) has been recognized as the causal agent of postweaning multisystemic wasting syndrome and can be divided into two major genotypic groups. We developed a method of restriction fragment length polymorphism (RFLP) analysis of PCV2 open reading frame 2 for easy discrimination between the two major groups. Genotyping of PCV2 isolates from 10 Japanese commercial pig farms was performed, and the analysis revealed that both PCV2 groups and at least five RFLP types of PCV2 are prevalent in Japan. On two farms, the genotypes of the PCV2 isolates in the spring of 2007 were different from those in the autumn of 2006. One genotype may have become dominant within only six months on these farms.  相似文献   
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