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排序方式: 共有4327条查询结果,搜索用时 31 毫秒
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.
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
3.
4.
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
5.
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
6.
E J Olender T Furukawa D J Woods D Fromm 《Proceedings of the Society for Experimental Biology and Medicine. Society for Experimental Biology and Medicine (New York, N.Y.)》1987,185(4):377-384
The effects of histamine and several H1 and H2 receptor agents on Na+/H+ and Cl-/HCO-3 exchange systems of isolated gastric mucosal surface cells were studied. The cells were acid-loaded by the NH4Cl prepulse technique and the spontaneous Na+- and HCO-3-induced dissipation of the intracellular proton gradient (pHi) was followed using the metachromatic dye acridine orange. Histamine (10(-2-5) M) stimulates HCO-3-induced dissipation of the pHi but has no effect on Na+-induced or spontaneous dissipation. The H1 agonist 2-(2-aminoethyl)pyridine and the H2 agonist dimaprit also have no effect on Na+-induced or spontaneous pHi dissipation. However, both of these agents mimic the effect of histamine on HCO-3-induced dissipation, but only at a higher concentration (10(-3) M). The combination of 2-(2-aminoethyl)pyridine and dimaprit produces a histamine-like effect at lower concentrations (10(-5) and 10(-4) M). The effects of histamine are blocked by either the H1 antagonists diphenhydramine and pyrilamine or the H2 antagonists cimetidine and SKF 93479. The results suggest that the effect of histamine on HCO-3-induced dissipation of a pHi in gastric mucosal surface cells is mediated through a coordinated mechanism involving both H1 and H2 receptor sites. 相似文献
7.
8.
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
9.
Interleukin-1 derived from human monocytic leukemia cell line JOSK-I acts as an autocrine growth factor 总被引:1,自引:0,他引:1
Y Furukawa M Ohta Y Miura M Saito 《Biochemical and biophysical research communications》1987,147(1):39-46
Interleukin-1 (IL-1) enhances the growth of human monocytic leukemia cell line JOSK-I cells, which were recently established in our laboratory and which were demonstrated to produce a high level of IL-1 constitutively, in liquid as well as semisolid culture systems. Concomitantly, IL-1 stimulated the prostaglandin E2 synthesis and nitroblue tetrazolium dye-reducing capacity of JOSK-I cells. This indicates that IL-1 may act as autocrine growth factor for monocytes, and also suggests the possibility that this autocrine stimulation may play an important role in the pathophysiology of monocytic leukemia in vivo. 相似文献
10.
Coomassie brilliant blue staining developed by Pena (1980) was applied to cultured hepatocytes of adult rats with some modifications. Many of organelles in the cytoplasms were clearly visible as blue granules by this method. Various cytoskeletal elements were also visualized clearly. Because of its simplicity, Coomassie blue staining proved to be a very powerful tool for study of morphological changes of cell organelles and cytoskeletal systems of cultured hepatocytes. 相似文献