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101.
We conducted two feeding experiments to evaluate the effects of cellooligosaccharide (CE) supplementation on growth performance in grazing beef calves. Calf sex and age and duration of the experimental period differed between the experiments. Experiment 1 (10 weeks) used 5.6‐month‐old castrated males; Experiment 2 (13 weeks) used 3.9‐month‐old females. Eight Japanese Black calves were assigned to either a control group (CON) or an experimental group (CE) fed CE at a rate of 10 g/day mixed with concentrate. Calves were stocked in fields in which Kentucky bluegrass was dominant. In both experiments, average daily gain tended to be greater in CE than in CON, especially in late stages of experiments, but no significant differences in body weight changes were observed. In Experiment 2, final heart girth was larger in CE than in CON calves. We monitored rumen microbial community composition in Experiment 2 and found increases in fibrolytic bacteria and methanogenic archaea in CE calves, but the overall microbial composition did not differ between the groups. Our results suggest that supplementation with CE may positively affect growth performance in weaned calves on pasture, but longer‐term CE supplementation may be required to exhibit the effect.  相似文献   
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Root growth and yield of sugar-beets were studied on two Belgian silt loam soils and one alluvial clay soil after subsoiling to a depth of 60 cm. The removal of the plough sole layer, characterized by penetration resistances > 3 MPa, resulted in an increase of the root quantity and a higher availability of water. As a consequence, a mean yield increase of 5 tons/ha for sugar-beets was found on the subsoiled plots in drier years. The yield increase was accompanied by a higher uptake of nutritive elements.  相似文献   
104.
Hesperidin is a biologically effective flavonoid. Several studies have reported that dietary hesperidin was converted to conjugated metabolites, such as hesperetin-glucuronides and sulfoglucuronides, during absorption and metabolism. However, the chemical structures of the conjugated metabolites, especially the sites of glucuronidation and sulfoglucuronidation in plasma, were unconfirmed. Therefore, the concentrations of the metabolites conjugated at various sites in plasma could not be individually quantified. In the present study, we identified the chemical structures and concentrations of the major conjugated metabolites in rat plasma after oral administration of hesperidin. Two hesperetin-glucuronides were prepared and identified as hesperetin-7-O-beta-D-glucuronide and hesperetin-3'-O-beta-D-glucuronide. Using these authentic compounds, the concentrations of hesperetin-7-O-beta-D-glucuronide and hesperetin-3'-O-beta-D-glucuronide in rat plasma were individually determined by liquid chromatography-mass spectrometry. In rat plasma, hesperetin-glucuronides were primarily comprised of hesperetin-7-O-beta-D-glucuronide and hesperetin-3'-O-beta-D-glucuronide. The concentration of hesperetin-7-O-beta-D-glucuronide was slightly higher than that of hesperetin-3'-O-beta-D-glucuronide. Furthermore, not only hesperetin conjugates but also homoeriodictyol conjugates were observed in rat plasma. The present study is the first report elucidating the chemical structures and changes in individual concentrations in rat plasma of glucuronides derived from orally administered hesperidin.  相似文献   
105.
The postnatal testicular development and actin distribution in the seminiferous epithelium were examined by light microscopy, using the testes of the Habu (Trimeresurus flavoviridis; snake) from 0-year-old to 3-year-old. At 0-year-old (about 1 month after birth), the testis was quite small in size, and the seminiferous epithelium was composed of only Sertoli cells and large spermatogonia. Actin immunoreactivity was observed in the peritubular myoid cells, but could not be detected in the seminiferous epithelium. At 1-year-old (about 10 months after birth), the testicular size increased to a great degree. In the seminiferous epithelium, spermatocytes newly appeared. Actin could still not be detected in the seminiferous epithelium. At 2-year-old (about 1 year and 10 months after birth), the testes continued to develop in size. In the seminiferous epithelium, elongate spermatids and round spermatids were frequently seen, in addition to Sertoli cells, spermatogonia and spermatocytes. Thus, active spermatogenesis was clearly recognized at this age. Moreover, the actin distribution in the seminiferous epithelium was observed at the site between Sertoli cells and spermatids, as well as that at adult stage. The immunoreactivity of actin in the peritubular myoid cells gradually increased from 0-year-old to 2-year-old. Conclusively, it seems likely that spermatogenesis in the Habu initiates at 2-year-old, accompanying with the appearance of actin in the seminiferous epithelium.  相似文献   
106.
An intestinal mass was found in the border area of the jejunum and ileum of a 110-week-old male F344 rat. Histopathologically, the mass protruded into the lumen and was covered with intestinal epithelium, exhibiting a normal architecture. The lesion was located in the submucosa and consisted of loose connective tissue, smooth muscle, scattered ganglion cells, and blood vessels of various sizes. Although these components showed an irregular and disordered structure, no cellular atypia, increased proliferation activity, or invasive growth to adjacent tissues were detected. Immunohistochemical analyses revealed that smooth muscle, ganglion, and endothelial cells were positive for α-smooth muscle actin and vimentin, S-100, and CD34 and von Willebrand factor, respectively, indicating maturation of these cells. Thus, the mass was diagnosed as a neuromuscular and vascular hamartoma of the small intestine. To the best of our knowledge, this is the first report of this type of lesion in rodents.  相似文献   
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The concept of chromosomes with a ring structure was born during the early studies of bacterial sexuality, and the discovery of fertility factors- episomes or plasmids-provided much later the key tools for gene cloning and biotechnology. But the plasmid-mediated transfer of antibiotic and other resistances, as well as pathogenicity, has served bacteria well in their own adaptive evolution.  相似文献   
110.
Journal of General Plant Pathology - Here, Nicotiana benthamiana plants became infected with apple stem grooving virus (ASGV) after pollination with pollen grains produced by ASGV-infected apple...  相似文献   
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