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1.
2.
K Kohmoto 《Endocrinologia japonica》1975,22(5):465-469
Mouse prolactin was purified by organ culture of pituitaries and electrophoresis of the medium. Mouse pituitaries were organ-cultured in 9-cm Petri dishes containing Waymouth's medium (MB 752/1) supplemented with penicillin (50 units/ml), streptomycin (100mug/ml), and bovine insulin (0.12 I.U./ml) for 8 days. Prolactin-rich culture medium was half-saturated with ammonium sulfate and centrifuged. The pellet was subjected to analytical disc electrophoresis (10% acrylamide). Gels were sectioned into 2-mm segments. Prolactin was eluted in 0.04M phosphate buffer (pH 7.2), dialyzed and lyophylized. Two hundred and forty ml medium in which 360 pituitaries were cultured yielded 29.3 mg lyophylized mouse prolactin. Although the preparation contained 2 other bands on acrylamide gel disc electrophoresis, a single precipitin line was seen in immunodiffusion and immunoelectrophoresis, showing the identity of their antigenicity. From these results, two other proteins in the preparation were suggested to be deamidated prolactin. 相似文献
3.
Fluctuation of algal alkaline phosphatase activity and the possible mechanisms of hydrolysis of dissolved organic phosphorus in Lake Barato 总被引:3,自引:3,他引:0
Shuji Hino 《Hydrobiologia》1988,157(1):77-84
For freshwater cyanobacteria, the autofluorescence of phycocyanin is quite high while the in vivo fluorescence (IVF) yield of chlorophyll-a is relatively low, apparently because of low chlorophyll concentrations associated with photosystem II. In eucaryotic phytoplankton, even those with phycobili-protein accessory pigments (e.g. some cryptophytes), the opposite is true. Thus, an IVF ratio which relates phycocyanin to chlorophyll-a signals could be a good index of relative cyanobacterial abundance in the field. Spectrofluorometric scans of whole cells from laboratory cultures indicated that the ratio Em660 @ Ex630/Em680 @ Ex430 could be a very sensitive cyanobacterial indicator. Tandem flowthrough fluorometers were then fitted with the appropriate interference filters and their discriminatory power was evaluated with mixtures of cyanobacterial and eucaryotic phytoplankton. Although subject to many of the constraints of other IVF assays, tandem fluorometry should be particularly appropriate for real-time mapping of the relative spatial and temporal distributions of broad phytoplankton taxa in continuous vertical of horizontal profiles in lakes. 相似文献
4.
Keisuke Kohmoto Kazuya Akimitsu Tetsuyuki Kohguchi Hiroshi Otani John M. Gardner 《Plant cell reports》1986,5(1):54-56
Amberlite XAD-7, a nonionic polyacrylate adsorbent, was found to be a very effective protectant for isolating mitochondria from tissues rich in oils and phenolics. Physiologically active, well-coupled mitochondria were successfully prepared from young green leaf tissues of citrus, apple, pear and tobacco.Abbreviations DNP
2,4-dinitrophenol
- CCCP
carbonyl cyanide m-chlorophenylhydrazone
- BSA
bovine serum albumin
- PVP
polyvinylpyrrolidone 相似文献
5.
Microiontophoretic study was performed to elucidate dopaminergic mechanism in the nucleus accumbens (Acc) of rats anesthetized with chloral hydrate. Iontophoretically applied dopamine produced an inhibition of glutamate-induced firing in 28 (62%) out of 45 Acc neurons tested. The dopamine-induced inhibition of 14 Acc neurons was clearly antagonized by simultaneous application of haloperidol, and a partial antagonism by sulpiride was observed in 3 out of 10 Acc neurons. These results indicate that dopamine produces an inhibition of the Acc neuron and that, compared to haloperidol, sulpiride is a less potent blocker of the postsynaptic dopamine receptor involved in the dopamine-induced inhibition. 相似文献
6.
The effect of a stressful manipulation on the metabolism of gamma-aminobutyric acid (GABA) in the rat brain was studied. Application of an immobilized stress to animals induced a significant increase in the striatal and hypothalamic GABA contents without affecting those in other central structures examined. It was also found that the increase in striatal GABA level preceded that in the hypothalamus. This increase in steady-state levels of GABA in the striatum and hypothalamus disappeared at 12 h after the termination of the application of stress for 3 h, which exhibited a maximal stimulatory action on the GABA contents in both central areas. The activity of L-glutamic acid decarboxylase was found to be significantly elevated in the striatum and hypothalamus following the stress application with a concomitant decrease in the content of L-glutamic acid, which is converted to GABA by the catalytic action of the latter enzyme. The in vivo turnover of GABA in the brain was estimated by taking advantages of the postmortem accumulation of GABA following decapitation and of the selective inhibitory action of a low dose of aminooxyacetic acid on the GABA degrading system, respectively. Analysis using these two different methods revealed that the cerebral turnover of GABA in vivo was not significantly altered under stressful situations despite of the increase in its steady-state level. These results suggest that central GABA system may respond to the input of painful stimuli resulting from the application of a severe physical and psychological stressor, in addition to the well-known functional alterations in catecholamine neurons. The functional significance of these alterations in the central GABA neurons is also discussed. 相似文献
7.
8.
S. K. Nutsugah K. Kohmoto H. Otani M. Kodoma R. R. Sunkeswari 《Journal of Phytopathology》1994,140(1):19-30
Production of a host-specific toxin by Alternaria tenuissima , the cause of pigeon pea leaf spot, was investigated in spore-germination fluids (SGF). The SGF selectively induced necrosis on pigeon pea leaves in a deteched leaf assay. Necrotic lesions were observed when a toxin from SGF was applied onto detached young leaves of the pigeon pea cultivar Bahar at concentration as low as 5 ng/ml. The resistant line Tanzania and nonhosts tolerated at least 20,000 times higher concentration of the toxin. The differential activity of the toxin on hosts and nonhosts of the fungus, as well as on susceptible and resistant cultivars or lines, suggested host-specific property of the toxin. At a concentration of 10 ng/ml, the toxin induced susceptibility of pigeon pea leaves to a non-pathogenic isolate of Alternaria alternata. The toxin possibly plays a role as a disease determinant of A. tenuissima , because the toxin was released from germinating spores as early as 3 h of incubation andthe, amount detected within 9 h was about 6 times of the concentration required for necrotic toxicity. 相似文献
9.
10.
Shuji Kitagawa Yasue Hongu Fujio Kametani 《Biochemical and biophysical research communications》1982,104(4):1371-1375
ADP-stimulated aggregation of bovine blood platelets was observed in media containing isotonic potassium salts of various monovalent anions. The aggregation depended on the anion in the medium, the order of aggregation being Cl?, Br?>I?>SCN?, . After 30-min incubation, the extent of aggregation of platelets in Cl? or Br? medium was little changed, whereas, that in SCN? or medium was remarkably decreased. This anion dependency of aggregation may be due to change in the membrane potential. 相似文献