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1.
Radioisotope techniques are well known as methods for evaluating symplastic ion absorption in roots. In the present study, a new method for evaluating symplastic cadmium (Cd) absorption in plant roots was developed using the enriched isotopes 113Cd and 114Cd. Seedlings of Solanum melongena were exposed to an enriched isotope solution of 113Cd at 25°C for 30 min. The roots were excised from each seedling and were then immersed in a cold buffer solution without Cd at 2°C for 120 min to suppress the metabolic activity of the roots. Finally, the roots were treated with a cold buffer solution containing enriched stable isotope 114Cd at 2°C for 120 min, whereby the apoplastically bound 113Cd was desorbed. We tested the validity of our method for evaluating symplastic Cd in roots compared with the conventional method based on differences in the amount of Cd absorbed at 2°C and 25°C using unlabeled Cd. There was no difference in the symplastic Cd content of the roots between the two methods. These results indicate that it is possible to evaluate the symplastic Cd content in roots using the enriched isotopes 113Cd and 114Cd.  相似文献   
2.
Buffalo meat is tasty and indistinguishable from beef, and has been described as being lean and low in cholesterol in comparison with beef. However, little is known about the plasma hormone and metabolic profiles related to fat metabolism in buffalo, and how their levels are affected by species and sex. In this study levels of plasma hormones and metabolites were compared between species and sexes. Ten growing crossbred Brahman cattle and ten growing crossbred buffaloes (five males and five females in each), with an average age of 22 months were used. The animals were fed on an experimental diet composed of corn silage, brewer's spent grain and a concentrate mixture at a 50:30:20 ratio on a dry matter basis during a fattening period of 6 months. Blood samples were collected every month during the experiment, and were analysed for plasma leptin, insulin, glucose, triglyceride (TG) and total cholesterol (TC) concentrations. Plasma leptin, insulin and TC concentrations increased during fattening and were significantly (P < 0.05) higher in cattle than in buffaloes. These concentrations in cattle showed a big difference between sexes in comparison with buffaloes, and were higher in females than in males. The plasma glucose and TG concentrations did not differ (P > 0.05) between cattle and buffaloes.

The crude fat content of longissimus muscle was significantly higher in cattle than in buffalo. Differences in body fat deposition seem to have an influence on plasma leptin, insulin and TC concentrations differently between cattle and buffaloes.  相似文献   

3.
A series of novel 4-O-alkoxytrityl chlorides (1) with different chain lengths was synthesized as a novel reagent for obtaining 6-O-alkylated cellulose with high regioselectivity via trityl groups in one reaction step without the use of any protective groups. These chlorides were reacted with methyl -d-glucoside, which was used as a model compound, to examine the reactivities toward the primary hydroxyl groups of cellulose to afford a series of 6-O-alkylated methyl -d-glucosides in high yields. The product compounds were found to have interesting solubilities and thermal properties. Thus, newly prepared trityl chloride derivatives were found to be useful regioselective derivatization reagents on the primary hydroxyl group in carbohydrates, especially in cellulose.  相似文献   
4.
ABSTRACT:   Recently, a serious disease spread extensively in aquaculture sites of the ascidian Halocynthia roretzi in Korea. To understand circumstances of ascidians in Korean aquaculture sites, residue levels of organotin compounds were analyzed, and detection of a marine birnavirus (MABV) in tissues of H. roretzi was attempted. Korean H. roretzi showed high concentrations of butyltins (mono, di, and tributyltins), especially in the gill, hepatopancreas, and digestive tract. However, there was no significant difference in the residues of butyltins in the hepatopancreas between diseased and non-diseased ascidians. The positive rate of MABV detection was high in the hepatopancreas, but also no significant difference was observed between diseased and non-diseased individuals. These observations suggest that an accumulation of tributyltin and a latency of MABV in H. roretzi tissues does not directly relate to the occurrence of the disease.  相似文献   
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The direct ancestor of rice (Oryza sativa L.) is believed to be AA genome wild relatives of rice in Asia. However, the AA genome wild relatives involve both annual and perennial forms. The distribution of the retrotransposon p-SINE1-r2, a short interspersed nuclear element (SINE) at the waxy locus was analyzed in diverse accessions of the AA genome wild relatives of rice (O. rufipogon sensu lato). Most annual wild rice accessions had this retrotransposon, while most perennial types lacked this element, contradicting results to the previous studies. Results presented here suggest that O. sativa has dual origin that lead to indica-japonica differentiation. Results suggest the indica line of rice varieties evolved from the annual genepool of AA genome and the japonica varieties from the perennial genepool of AA genome wild rice.  相似文献   
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Either before or after curing their cut surfaces for 5 days, 7 cm- and 15-cm-long decapitated Hylocereus trigonus cuttings were treated by soaking their apical or basal ends in benzyladenine (BA) solution. They were then planted and grown in a greenhouse.For the 7 cm-long cuttings, BA (25–100 mg l?1) applied to the apical ends for 24 h increased the ratio of cuttings with sprouted buds to 64–100%, the number of sprouted buds to 1.9–3.1 and of shoots to 1.6–2.8, and the shoot length to 35–60 mm, compared to the water control which showed 13%, 1.0, 1.0 and 12.5 mm, respectively. Soaking the basal part had only a small effect.Naphthylacetic acid (NAA) applied to the basal ends of cuttings immediately after cutting increased the number of sprouted buds and shoots by inducing early rooting. The number and length of BA-induced axillary shoots in the longer cuttings was greater than those in the shorter ones.In the 15-cm-long cuttings, increasing the soaking time from 5 min to 24 h resulted in a greater promotive effect of BA on shoot formation. BA applied before curing showed the same effect as that given after curing but caused necrosis of the tissue just under the cut surface. Enlarging the area soaked in BA solution from 5 cm to 10 cm decreased the number of sprouting buds and shoots.  相似文献   
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10.
Screw and laser (SL) column by making screw threads and forming small holes using laser irradiation on the base metal and conventional beads coating (BC) columns were embedded into the shaft of canine femurs, and compared the implant fixation to the host bone. The interfacial strength in SL columns was almost equivalent as BC columns, and bone-column contact rate was higher than BC columns significantly at twelve weeks after implantation. The newly devised SL surface had almost equivalent bone fixation strength comparable to the conventional BC surface. Also, this surface should provide a useful porous surface for use in artificial joints since there is no risk of surface structure detachment.  相似文献   
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