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1.
T. Tomiyama 《Journal of fish biology》2013,83(5):1334-1343
Variation of scales on the blind side of Pseudopleuronectes yokohamae in relation to sex, maturity and body size was examined. Immature males often have cycloid scales, while mature males have mostly ctenoid scales. Large females also often have ctenoid scales (but with fewer spines compared with males), and small females have mostly cycloid scales. The number of spines (ctenii) on the blind‐side scale increases with body size in both sexes, indicating an ontogenetic change in scale morphology. As P. yokohamae spawn demersal eggs with males positioning themselves above the females on the ocular side, it is hypothesized that ctenoid scales on the blind side in mature males function for maintaining contact with females during spawning. 相似文献
2.
Systemic Induction of Resistance in Potato Plants Against Phytophthora infestans by Local Treatment with Hyphal Wall Components of the Fungus 总被引:2,自引:0,他引:2
Potato plants (cv.‘Irish Cobbler’ with no major resistance genes to Phytophthora infestans), the lower or upper leaves of which were previously treated with hyphal wall components (HWC) of the fungus by rubbing with carborundum, acquired an induced resistance in other untreated leaves against cultivar-pathogenic races of P. infestans when challenged by spraying with a zoospore suspension. Such induced resistance was significantly shown to exist from at least 1 to 20 days after induction treatment with HWC. Thus, the treated plants were protected from severe late blight disease while non-induced control plants finally died of the disease. The induced resistance was due to a reduction of the number of successfully germinating zoospores, and subsequent penetration and then occurrence of hypersensitive-like cell response to the penetrating organisms. These results suggested that local leaf tissues of potato plants reacting to HWC may provide some systemic information that activates or enhances some resistance to P. infestans. 相似文献
3.
We measured the urinary excretions of dopamine, noradrenaline and adrenaline, their conjugated metabolites, urinary excretion of sodium and creatinine clearance simultaneously in 21 patients with Type 2 (non-insulin-dependent) diabetes and 6 normal subjects. The mean (+/- SEM) value for urinary excretion of dopamine (52.4 +/- 8.8 micrograms/day) in diabetic patients with nephropathy (Group C, n = 12) was significantly lower (P less than 0.01) than in the normal subjects (Group A, 179.7 +/- 15.5 micrograms/day) and in diabetic patients without nephropathy (Group B, n = 9, 131.5 +/- 16.5 micrograms/day). The mean values for the urinary excretions of noradrenaline and adrenaline were also significantly lower (P less than 0.01) in Group C than in Groups A and B. In addition, the mean urinary excretion of conjugated metabolite of dopamine in Group C was significantly lower (P less than 0.05) than in Group A. There was a trend toward the observation that the mean 24-h urinary excretion of sodium in Group C (121.6 less than 12.9 mEq) was lower as compared with that in Group A (140.8 +/- 8.9 mEq) or B (150.7 +/- 17.9 mEq). A multiple regression analysis revealed that the 24-h urinary excretion of dopamine correlated significantly with creatinine clearance, systolic (P less than 0.01) and diastolic (P less than 0.05) blood pressures. The results indicate that synthesis or secretion of renal dopamine might decrease with a progression of diabetic nephropathy.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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Summary
Panax ginseng hairy root cultures were established by infecting petiole segments with Agrobacterium rhizogenes strain 15834. Hairy root segments including root tips placed onto phytohormone-free 1/2 Murashige and Skoog solid medium and stored at 4 °C in the dark for 4 months, resumed elongation when the temperature was raised to 25 °C in the dark. For cryopreservation, a vitrification method was applied. Root tips precultured with 0.1 mg/l 2,4-D for 3 days and dehydrated with PVS2 solution for 8 minutes prior to immersion into liquid nitrogen had a survival rate of 60 % and could regenerate. The hairy roots regenerated from cryopreserved root tips grew well and showed the same ginsenoside productivity and patterns as those of the control hairy roots cultured continuously at 25 °C. The conservation of T-DNAs in the regenerated hairy roots was proved by PCR analysis.Abbreviations 1/2 MS
a half strength Murashige and Skoog (1962)
- B5
Gamborg B5 (Gamborg et al. 1968)
- WP
woody plant (Lloyd and McCown 1980)
- RC
root culture (Thomas and Davey 1982)
- RCI
root culture medium containing 100 mg/l myoinositol
- HF
phytohormone-free
- IAA
indole-3-acetic acid
- IBA
indole-3-butyric acid
- 2,4-D
2,4-dichlorophenoxyacetic acid
- TIBA
2,3,5-triiodobenzoic acid
- PCR
polymerase chain reaction
- PVS2
plant vitrification solution 2 (Sakai et al., 1990)
- FDA
fluorecein diacetate 相似文献
8.
Mondher Jaziri Kayo Yoshimatsu Jacques Homès Koichiro Shimomura 《Plant Cell, Tissue and Organ Culture》1994,38(2-3):257-262
Hairy root cultures of Atropa belladonna L. were established by infection either with Agrobacterium rhizogenes ATCC 15834 or MAFF 03-01724, and transgenic plants were obtained from both hairy root cultures. Doubly transformed roots were induced by re-infection of the leaf segments of transgenic Atropa belladonna plants (A. rhizogenes 15834) with MAFF 03-01724. Shoots and viviparous leaves were regenerated from the doubly transformed roots. The genetic transformation was determined by the opine assay (agropine, mannopine and/or mikimopine) and polymerase chain reaction. Physiological changes and tropane alkaloid biosynthesis in the hairy roots (singly and doubly transformed) were investigated. The alkaloid content in the doubly transformed root strain was intermediate as compared to the root strains which were singly transformed. On the other hand endogenous IAA levels in doubly transformed roots were significantly decreased compared to both singly transformed roots.Abbreviations BA
benzyladenine
- IAA
indoleacetic acid
- NAA
naphthaleneacetic acid
- PCR
polymerase chain reaction
-
t-ZR
trans-zeatin 相似文献
9.
Both the matrix structure of loofa sponge and the flocculating property of cells were necessary for efficient immobilization. The addition of chitosan to a reactor containing a bed of loofa sponge and a Candida brassicae cell suspension induced cell flocculation and the cells were efficiently immobilized. During ethanol production by the immobilized cells, the free cell concentration in the broth was controlled at the desired level by intermittent addition of chitosan to the reactor. The immobilized cell concentration increased but their specific ethanol productivity decreased with an increase in the chitosan concentration. The maximum ethanol productivity was obtained at a low chitosan concentration of 0·03 g/litre. With this optimal concentration, the cell concentration, ethanol yield and productivity were, respectively, 2, 1·3 and 3 times higher than those of the suspension culture. 相似文献
10.
Yoshiaki Inayama Izumi Tomiyama Hitoshi Kitamura Yukio Nakatani Takaaki Ito Akinori Nozawa Yasuhiro Usuda Masayoshi Kanisawa 《Histochemistry and cell biology》1995,104(3):191-198
The purpose of this study was to investigate alkaline phosphatase (ALPase) reactivity in rabbit airway epithelial cells. Acetone-fixed, methyl benzoate and xylene-cleared (AMeX-treated) paraffin sections of trachea, bronchus, and lung tissue were stained by an azo dye coupling method for ALPase and examined by light microscopy. Electron histochemical staining was also performed in order to study the sensitivity and specificity of reactivity in each cell type. ALPase reactivity at the light microscopic level was observed exclusively in trachco-bronchial basal cells, and not in bronchiolar basal cells. By electron microscopy, ALPase reactivity was noted in 97.9% of basal cells in the trachea, 97.0% of basal cells in the bronchus, and 94.5% of basal cells and 15.4% of Clara cells in the bronchiole. This was also true for dispersed tracheal epithelial cells. Reactivity was rarely observed in ciliated cells, non-goblet-type secretory cells, and undetermined cells. The reactivity was heatlabile, levamisole-sensitive, and of a non-specific type. These findings indicate that basal cells of rabbit trachea and bonchus have fairly high specificity for ALPase of a non-specific isozyme (92.2% and 95.6%, respectively). Therefore, ALPase is considered to be a useful marker for these cells. 相似文献