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31.
A genomic fragment containing the dihydroflavonol 4-reductase B (DFR-B) gene was cloned from the sweet potato (Ipomoea batatas) and its nucleotide sequence was analyzed. The exons and flanking regions were highly homologous to those of previously reported DFR-B genes of the Japanese morning glory, whereas the introns and the intergenic region were less conserved. In addition to the sequences of three miniature inverted-repeat transposable elements (MITEs) and one direct repeat previously reported in the DFR-B gene of Japanese morning glory, two mobile element-like sequences were newly identified in the sweet potato DFR-B gene. At least four allelic sequences were found to exist by amplification of the DFR-B gene from various sweet potato cultivars. One of these allelic sequences had a 2-kb deletion in the intergenic region and was observed in the cultivars with high anthocyanin content in their storage roots. 相似文献
32.
Masaru Nakano Keizo Hosokawa Tomo Oomiya Saburo Yamamura 《Plant Cell, Tissue and Organ Culture》1995,41(3):221-227
A protoplast-to-plant system was developed in Gentiana using a gellan gum-embedding culture. Viable protoplasts could be routinely isolated from in vitro-grown plantlets, and they were embedded in 0.2% gellan gum-solidified B5 medium containing 2 mg l-1 NAA, 0.1 mg l-1 TDZ, 0.1 M sucrose and 0.4 M mannitol. Weekly addition of fresh liquid medium was essential for preventing cell browning. Colony growth was promoted by lowering mannitol concentration of the culture media after one month, and visible colonies were produced after 2 months of culture. Shoot regeneration from protoplast-derived calluses was stimulated by 1 to 10 mg l-1 TDZ in combination with 0.1 mg l-1 NAA. Protoplast-derived plants were recovered following rooting of the shoots in plant growth regulator-free medium and they were successfully transferred to soil.Abbreviations BA
benzylaminopurine
- FDA
fluorescein diacetate
- FW
fresh weight
- MES
2-N-morpholinoethane sulfonic acid
- NAA
-naphthaleneacetic acid
- TDZ
N-1,2,3-thiadiazol-5-yl-N-phenylurea (also called thidiazuron) 相似文献
33.
Y. Kobayashi Yufuko Takahashi Satoshi Chikayama Motomi Ikeda Nobuhiko Uoshima Shinya Kimura Koji Tanaka Katuya Wada Masaru Ozawa Tatuo Sugano Naoyuki Maruo Motoharu Kondo 《Histochemistry and cell biology》1997,108(2):115-120
We devised a new microfluorometric method for determining the ploidy of megakaryocytes identified immunologically in bone
marrow smears. The smears were immunostained by incubation with mouse monoclonal anti-glycoproteins (GP) IIb antibodies, followed
by fluorescein isothiocyanate-conjugated goat anti-mouse IgG antibodies. They were then stained with 4′,6-diamidino-2-phenylindole
(DAPI). Megakaryocytes were identified by their GPIIb immunofluorescence using a microfluorometer and, after the filters were
changed, their DNA content was assayed by measuring the intensity of DAPI fluorescence. This intensity was shown to be proportional
to the DNA content when the aperture of the objective lens was reduced. We compared these results with those obtained when
megakaryocytes were identified morphologically, using DAPI staining after Wright-Giemsa destaining. In all 12 normal controls,
the ploidy peaks were shown to be 16N by both methods, and the mean ploidy detected by the immunological method was only reduced
0.961 times relative to the estimate from the morphological method. In contrast, in eight myelodysplastic syndrome (MDS) patients,
the ploidy peaks were either 8N or 4N and the mean was reduced by 0.906 times (P=0.018). Thus we could immunologically identify small megakaryocytes which we could not identify morphologically. Therefore,
this method is useful for measuring megakaryocytic ploidy, especially in the pathological megakaryocytes of MDS patients.
Accepted: 29 April 1997 相似文献
34.
To study the reliabiliity of formulas for calculating mean skin temperature (T
sk), values were computed by 18 different techniques and were compared with the mean of 10,841 skin temperatures measured by
infrared thermography. One hundred whole-body infrared thermograms were scanned in ten resting males while changing the air
temperature from 40° C to 4° C. Local, regional average and mean skin temperatures were obtained using an image processing
system. The agreement frequency, defined as the percentage of the calculated T
sk values which agreed with the corresponding infrared thermographic T
sk within ±0.2° C, ranged for with the various formulas from 7% to 80%. In many sites, the local skin temperature did not coincide
with the regional average skin temperature. When the local skin temperatures which showed the highest percentage similarity
to the regional average skin temperature within ±0.4° C were applied to the formula, the agreement frequency was markedly
improved for all formulas. However, the agreement frequency was not affected by changing the weighting factors from specific
constants to individually measured values of regional surface area. By applying the physiologically reliable accuracy range
of ±0.2° C in the moderate and ±0.4° C in the cool condition, agreement frequencies of at least 95% were observed in formulas
involving seven or more skin temperature measurement sites, including the hand and foot. We conclude that calculation of a
reliable mean skin temperature must involve more than seven skin temperature measurement sites regardless of ambient temperature.
Optimal sites for skin temperature measurement are proposed for various formulas.
Received: 2 December 1996 / Accepted: 25 June 1997 相似文献
35.
S Nakamura S Sakata T Komaki N Kojima K Kamikubo S Miyazaki K Yasuda H Tsukada S Shiraki K Miura 《Endocrinologia japonica》1984,31(6):675-679
We measured the levels of serum thyroglobulin (Tg) in 52 pregnant females at various stages and compared them with those of 15 age-matched nonpregnant females. Serum Tg was measured by a solid-phase immunoradiometric assay. In pregnant females, mean serum Tg levels at the first, second, early third, and late third trimesters were 8.4 (range; 1.3-18.0), 9.2 (1.7-25.6), 10.1 (1.8-22.8), and 12.1 ng/ml (5.3-25.2), respectively. The statistical comparison was made after logarithmic transformation of the data. The mean value only at the late third trimester was significantly higher than that of controls (mean; 6.0 ng/ml, range; 1.5-23.6), but each value was within the normal range. Although serum Tg levels have been reported to be high at the end of pregnancy, our results indicate that the Tg levels in females could be clinically interpreted without regard to the coexistence of pregnancy. 相似文献
36.
In Rana pipiens, mating behavior could be induced readily in intact males by several pituitary implantations, but never in castrates. Systemic testosterone injection (1 mg daily), with or without pituitary implantation, failed to restore mating behavior in castrated frogs. On the other hand, intracranial implantation of testosterone (approximately 60-μg pellets in which testosterone is mixed with cholesterol 1:1) in castrates evoked mating behavior, including mating calls and clasping. The most effective implantation site was the rostral part of the preoptic nucleus. Thus, the rostral part of the preoptic nucleus is the androgen-sensitive site which governs sexual behavior in this species. The relative ineffectiveness of systemic injection of testosterone is discussed. 相似文献
37.
Takamichi Ichinose Akira K. Suzuki Hirokazu Tsubone Masaru Sagai 《Life sciences》1982,31(18):1963-1972
Strain differences of mice in their susceptibility to nitrogen dioxide (NO2) were examined by measuring the activities of antioxidative protective enzymes, and the amounts of antioxidants and lipid peroxides in lungs. Four strains of mice: ICR, BALB/c, ddy and C57BL/6 were used in this study and their LC50 values after exposure to NO2 for 16 hr were: 38, 49, 51 and 64 ppm, respectively (1).Genetic strain differences were observed in the enzyme activities, the antioxidant contents and lipid peroxide contents among these four different strains. The activities of glutathione peroxidase (GPx), glutathione S-transferase, and superoxide dismutase (SOD), and the contents of non-protein sulfhydryls (NPSH), α-tocopherol (α-Toc) and total lipids in lungs of the four strains were related to their LC50, while TBA reactants in lungs of the four strains were inversely related to their LC50.After exposure to 20 ppm NO2 for 16 hr, the activities of the protective enzymes and the contents of NPSH decreased, while the level of α-Toc increased markedly. The activities of GPx, 6-phosphogluconate dehydrogenase, SOD and disulfide reductase, and the contents of NPSH, α-Toc and total lipids were also related to their LC50. On the other hand, TBA reactants increased higher than those of the control groups and were inversely related to their LC50.These results suggest that the protective enzymes and the antioxidants are important factors as defence mechanism in lungs to NO2 and that the intensity of the protective systems in pigmented strains is generally greater than that in albino strains. 相似文献
38.
Erythrocyte ghosts containing a known number of molecules of purified fragment A of diphtheria toxin with a constant amount of FITC-BSA as a fluorescence marker were prepared by dialyzing a mixture of erythrocytes and these substances against hypotonic solution. These substances were then introduced into diphtheria toxin-resistant mouse L cells by virus-mediated cell fusion of the cells with the ghosts, and mononuclear recipients that had fused with only one erythrocyte ghost were separated in a fluorescence-activated cell sorter (FACS) on the basis of their cell size and fluorescence intensity. After separation, the viability of cells containing known numbers of fragment A was examined by measuring colony-forming ability. The results demonstrated that a single molecule of fragment A was sufficient to kill a cell.This fact was confirmed by introduction into cells of fragment A from an immunologically related mutant toxin, CRM 176 (fragment A-176); this has a completely functional fragment B region, but in cell extracts, the enzymic activity of its fragment A is about 10 fold less than that of wild toxin. The cytotoxicity of CRM 176 is about two hundredths of that of the wild-type (Uchida, Pappenheimer and Greany, 1973). As expected, about 100–200 fold excess of fragment A-176 was needed to kill the cells. 相似文献
39.
T Ohzeki K Hanaki H Motozumi H Matsuda-Ohtahara N Ishitani K Shiraki 《Hormones et métabolisme》1992,24(10):484-487
Patients with the general type (patient #1 and #2) and the selective pituitary type (#3) of thyroid hormone refractoriness (TR) were studied to clarify defects at peripheral and pituitary receptors. Products of T3 and TSH (n = 63) were calculated when T3 was above the normal limit (T3 > 1.8 ng/ml, 2.8 nmol/l) as one of the indices of pituitary resistance. Means of T3 (ng/ml) x TSH (mU/l) of patient #1 (mean; 40.8), #2 (15.0) and #3 (8.6) were significantly greater than patients with Graves' disease (2.1), suggesting pituitary refractoriness in the 3 patients. The products of patient #1 and #2 were also significantly larger than patient #3, demonstrating that the pituitary insensitivity in the latter (#3) was less than the former patients. Means of serum cholesterol in patients #1 and #2 were higher than patient #3 and patients with Graves' disease. Products of T3 (ng/ml) and cholesterol (mg/ml) (n = 28) in the patient #1 (541.9) and #2 (461.0) were significantly greater than the patient #3 (292.8) and the patients with Graves' disease (275.3). The results demonstrate generalized refractoriness in the patient #1 and #2 and selective pituitary resistance in the patient #3. It is suggested that our patient with the pituitary type (#3) had less severely affected receptors at the pituitary than our two patients with the general type. These results are consistent with the previous hypothesis that the pituitary type of TR is a partial form of this disease. 相似文献
40.
Jun Ishizaki Mikio Tamaki Masaru Shin Hiroshige Tsuzuki Kazumasa Yoshikawa Hiroshi Teraoka Nobuo Yoshida 《Applied microbiology and biotechnology》1992,36(4):483-486
Summary Recombinant human glucagon was succesfully produced with a high level of expression in Escherichia coli as a fusion protein with human interferon . The synthetic gene was designed to release glucagon, which does not contain glutamic acid residues, from fusion protein with the Staphylococcus aureus strain V8 protease that specifically cleaves the peptide bond on the carboxyl side of the glutamic acid residue. The resulting glucagon was purified to homogeneity by a combination of C18 reverse-phase HPLC and ion-exchange HPLC. The yield of intact glucagon obtained from 11 of culture was approximately 12 mg. The structure of recombinant human glucagon was confirmed by HPLC and amino acid composition/sequence analyses.
Offprint requests to: J. Ishizaki 相似文献