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1.
Hoshino Atsushi; Abe Yukihide; Saito Norio; Inagaki Yoshishige; Iida Shigeru 《Plant & cell physiology》1997,38(8):970-974
The Japanese morning glory carrying the recessive mutable speckledallele with the dominant speckled-activator bears colorlessflowers with fine and round colored spots distributed over thecorolla whereas the plant without the speckled-activator producespale yellow flowers. Previous chemical analysis has indicatedthat a mutation in the gene for flavanone 3-hydroxylase (F3H)is a likely candidate for the speckled allele. However, theF3HmRNA without sequence alteration accumulates normally inthe pale yellow flowers, indicating that the speckled alleleis neither the F3H gene nor a regulatory gene acting on theF3H gene expression. (Received April 4, 1997; Accepted June 2, 1997) 相似文献
2.
Yuji Inaba Yoshio Tanaka Sukemitsu Ishii Tomiaki Morimoto Kunihiko Sato Tuneyoshi Omori Minoru Matumoto 《Microbiology and immunology》1970,14(5):351-360
Replication of Ibaraki virus was not inhibited by 5-iodo-2′-deoxyuridine, indicating that the virus is an RNA virus. The virus was resistant to ether, chloroform and deoxycholate, sensitive to trypsin, very labile at acidic pH but stable at pH 6.4 or higher, and was resistant to repeated freezing and thawing. The virus was readily inactivated at 56 C or higher, was fairly stable at 37 C, and very stable at 4 C, while it rapidly lost infectivity when stored frozen at —20 C. The virus was readily sedimented by centrifugation at 40 000Xg for 60 min. It readily passed through membrane filters of 200 mμ pore size, passed through 100 μfilters but only with some titer loss and did not through 50 mμ filters. In these tests, the bluetongue virus used as a control behaved in the same manner as Ibaraki virus. These findings provide additional evidence for the similarity of Ibaraki virus to bluetongue virus which had been previously demonstrated on the basis of seasonal incidence, symptomatology and pathology of the diseases caused by these viruses and the behavior of the viruses in cell cultures, embryonated eggs and laboratory animals. The present study, however, provided no evidence for any serological relation between these two viruses. More Information is needed to reach a final decision on the classification of Ibaraki virus, particularly regarding the morphology of the virion, the doublestrandedness of the viral RNA and other basic features. 相似文献
3.
Xiuyun Ye Shigeru Yoshida T. B. Ng 《The international journal of biochemistry & cell biology》2000,32(11-12)
A mild and rapid method is described for isolating various milk proteins from bovine rennet whey. β-Lactoglobulin from bovine rennet whey was easily adsorbed on and desorbed from a weak anion exchanger, diethylaminoethyl-Toyopearl. However, α-lactalbumin could not be adsorbed onto the resin. α-Lactalbumin and β-lactoglobulin from rennet whey could also be adsorbed and separated using a strong anion exchanger, quaternary aminoethyl-Toyopearl. The rennet whey was passed through a strong cation exchanger, sulphopropyl-Toyopearl, to separate lactoperoxidase and lactoferrin. α-Lactalbumin and β-lactoglobulin were adsorbed onto quaternary aminoethyl-Toyopearl. α-Lactalbumin was eluted using a linear (0–0.15 M) concentration gradient of NaCl in 0.05 M Tris–HCl buffer (pH 8.5). Subsequently, β-lactoglobulin B and β-lactoglobulin A were eluted from the column with 0.05 M Tris–HCl (pH 6.8), using a linear (0.1–0.25 M) concentration gradient of NaCl. The yields were 1260 mg α-lactalbumin, 1290 mg β-lactoglobulin B and 2280 mg β-lactoglobulin A from 1 l rennet whey. 相似文献
4.
5.
The major glycoproteins of horse and swine erythrocyte membranes were isolated and examined chemically and immunologically. The major glycoprotein of horse erythrocyte membranes had a molecular weight of 33 000 and consisted of 46.2% protein and 53.8% carbohydrate, of which 9.4% was hexose, 10.1% hexosamine and 33.7% sialic acid. This glycoprotein was associated with activity for the infectious mononucleosis heterophile antigen.There were two different major glycoproteins in swine erythrocyte membranes. One major glycoprotein had a molecular weight of 46 200 and consisted of 34.2% protein and 65.8% carbohydrate, of which 18% was hexose, 19% hexosamine and 27.2% sialic acid. This glycoprotein had phytohemagglutinin (Phaseolus vulgaris) binding activity. The other glycoprotein had a molecular weight of 29 000 and consisted of 50.4% protein and 49.6% carbohydrate, of which 6.4% was hexose, 7.0% hexosamine and 36.3% sialic acid. This glycoprotein had weak or absent phytohemagglutinin binding activity. 相似文献
6.
Tuneyoshi Omori Yuji Inaba Tomiaki Morimoto Yoshio Tanaka Hiroshi Kurogi Minoru Matumoto 《Microbiology and immunology》1967,11(2):133-142
Five strains of bovine diarrhea virus were isolated from Japanese cattle using bovine tissue cultures. These are the first isolations of this virus from Japanese cattle to be reported. Of importance is the finding that the new isolates, which are non-cytopathogenic, induce an exaltation of Newcastle disease virus in bovine testicular cell culture. This finding has provided a laboratory tool whereby the assay of the virus and its neutralizing antibody can readily be performed. 相似文献
7.
Effects of nitrates and calcium channel blockers on Ca2+-ATPase in the microsomal fraction of porcine coronary artery smooth muscle cells 总被引:1,自引:0,他引:1
The effects of the antianginal drugs nitroglycerin, nicorandil, diltiazem, verapamil and nicardipine on the activity of calcium-stimulated magnesium-dependent ATPase (Ca2+-ATPase) were investigated in the microsomal fraction from porcine coronary artery smooth muscle cells. Two discrete Ca2+-dependent ATPase components were observed: [1] a high affinity component, which was a specific Ca2+-ATPase, [with a half saturation constant for Ca2+ (Km) of 0.44 microM, and maximum velocity (Vmax) of 124.3 pmol of phosphate (Pi) released/micrograms of protein/30 min]: [2] a low affinity component in which Ca2+ could be replaced by Mg2+ without loss of its activity. Nitroglycerin and nicorandil (1 microM and 10 microM) both stimulated the activity of the Ca2+-ATPase significantly [142 +/- 12 (mean +/- standard error), and 137 +/- 10% of the control with nitroglycerin, and 152 +/- 17 and 135 +/- 20% with nicorandil] at a Ca2+ concentration of 0.3 microM. Diltiazem, verapamil and nicardipine did not cause significant stimulation. Nitroglycerin and nicorandil (1 microM), significantly decreased the Km for Ca2+ from the control value of 0.44 +/- 0.06 microM to 0.26 +/- 0.03 and 0.22 +/- 0.03 microM, respectively. Nitroglycerin and nicorandil may dilate coronary arteries by stimulating this Ca2+ extrusion pump enzyme through reduction of intracellular Ca2+ in smooth muscle cells. 相似文献
8.
The degree of methylation at the c-myc proto-oncogene was found to change in human lymphoproliferative diseases, when examined using a methylation-sensitive restriction enzyme. In peripheral blood mononuclear cells (PBMC) c-myc DNA showed hypomethylation in human lymphoproliferative diseases, in comparison to normal subjects matched in age and sex. In cases of chronic lymphocytic leukemia (CLL), the change was amplified in the crisis. When the DNA was examined at the actin gene, no significant change was observed. The results suggest that the change in c-myc proto-oncogene methylation might become an important clue in understanding the relationship between levels of gene expression and methylation in human lymphoproliferative diseases. 相似文献
9.
The effects of defoliation treatments on plant growth in sunflower (Helianthus annuus) were studied in the field. Four defoliation treatments, 0 (control), 37.4, 56.1 and 93.4% of the total leaf dry weight,
were applied to plants that had small third leaves. Decreased leaf weight/whole plant weight (F/W) ratios in defoliated plants
rapidly recovered to almost the same ratio as that observed in the control within 12 to 16 days after defoliation according
to the degree of defoliation. The mechanism involved in the recovery of the F/W ratio in defoliated plants mainly consisted
of three parameters: enhancement of (1) carbon distribution ratios in the leaves, (2) photosynthetic activity in the remaining
leaves, and (3) retranslocation of carbon from the stem and/or roots to leaves.
Inhibitive effects of defoliation on relative growth rate and net assimilation rate were seen at an early stage, but subsequently
both rates became larger in defoliated plants than in controls. Defoliated plants tended to show rapid development and expansion
of new leaves, and to show increased specific leaf area and protein synthesis in individual leaves. The sugar content of leaves
in defoliated plants was higher than that in controls, while the content in both stem and roots was lower. These responses
seem to be advantageous for development of the photosynthetic system. Heights of defoliated plants were clearly depressed
according to the degree of defoliation, and this was attributed largely to differences in the elongation rates of the internodes
resulting from defoliation. 相似文献
10.
H Nakamura M Koga S Higa B Sato K Noma Y Morimoto S Kishimoto E Nakano T Sonoda 《Endocrinologia japonica》1987,34(4):545-551
A 58-year-old woman was admitted to our hospital complaining of headache, dizziness and intermittent elevation of blood pressure. Multiple café-au-lait spots and neurofibromas had appeared on the back and the limbs since the age of 30 years. At the age of 54 years she underwent total thyroidectomy because of papillary carcinoma of the thyroid gland. On admission, the levels of plasma norepinephrine and epinephrine, urinary norepinephrine and normetanephrine were all within the normal range. However, urinary excretion of metanephrine was markedly increased to 1.49 +/- 0.45 (Mean +/- SD) mg/day and that of epinephrine was also slightly increased. The computed tomographic scans of the abdomen and the scintigraphy with 131I-metaiodobenzylguanidine revealed a tumor mass in the region of the right adrenal gland. The tumor was histologically confirmed to be pheochromocytoma at the operation. In her family history, her mother and one of her two sisters had von Recklinghausen's disease and another sister suffered from follicular carcinoma of the thyroid gland. As far as we know, this paper is the first report of a patient with von Recklinghausen's disease associated with both pheochromocytoma and non-medullary carcinoma of the thyroid gland, and her family. 相似文献