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81.
Donovan des S. Thomas Toshio Murashige 《In vitro cellular & developmental biology. Plant》1979,15(9):654-658
Summary The low-molecular-weight volatiles released by a variety of plant tissue cultures were examined by gas chromatography. Callus
cultures invariably produced carbon dioxide, ethylene, acetaldehyde and ethanol. In cultures with developed shoots, ethanol
was absent and acetaldehyde was detected only rarely. 相似文献
82.
83.
A new assay system of phospholipid exchange activities is described. The exchange activities were quantitated by measuring the stimulation of phospholipid transfer between two separate populations of liposomes, which contained, as the major constituents, phosphatidylcholine, phosphatidylethanolamine, phosphatidylinositol, sphingomyelin, and cholesterol in molar ratios of 6: 2: 1: 1: 5. One population of the liposomes was made reactive to concanavalin A by the incorporation of 1.8 mol% from Micrococcus lysodeikticus. The concanavalin A-reactive liposomes, a phospholipid donor, were doubly labelled with [6-3H]galactosylglucosyl ceramide and that class of 32P-labelled phospholipids whose exchange was being measured. The 3H-labelled glycolipid served as a non-exchangeable reference marker. The other population of the liposomes, a phospholipid acceptor, was concanavalin A nonreactive. These two populations of liposomes were incubated with the cytosol protein of rat liver in a total volume of 0.2 ml.After the incubation, two different procedures were used to separate the two liposomal populations. In one procedure concanavalin A was added to agglutinate the reactive liposomes; the flocculated lectin-liposome complex was separated from the non-reactive liposomes by brief centrifugation. In the other procedure the reactive liposomes were trapped by binding to concanavalin A covalently coupled to Sepharose 2B; the complex was separated from the nonreactive liposomes by filtration through a filter paper under suction. In both assay procedures the amount of phospholipid transferred from the donor to the acceptor liposomes was calculated from the decrease of 32P/3H ratio of the concanavalin A-reactive liposomes during the incubation. By the assay system it is possible to determine phosphatidylcholine and phosphatidylinositol exchange activities in 100 μg of rat liver cytosol protein. 相似文献
84.
At low concentrations (25–100 μM) methylmercury chloride caused a steady increase in the threshold for excitation and on eventual block of action potentials without changing the resting membrane potential in squid giant axons. In the axons exposed to 25 μM methylmercury chloride, peak transient and steady-state conductances were decreased by 58.8 ± 5.1% and 35.9 ± 4.3% (mean ± SEM, 4 axons), respectively and leakage conductance increased to about five times of the control value. Higher concentrations of methylmercury chloride decreased the resting membrane potential. A concentration of 0.5 mM depolarizing the nerve membrane by 16 ± 2 mV (mean ± SEM, 3 axons) in 40 minutes. These changes in ionic conductances and membrane potential were irreversible on washing the axon with drug-free sea water. 相似文献
85.
An endo-(1→6)-β-D-glucanase (EC 3.2.1), isolated from the culture filtrate of Mucor hiemalis, was purified by ammonium sulphate fractionation and gel filtration. The homogeneity of the enzyme was confirmed by disc electrophoresis. The enzyme had a wide range of temperature and pH stability, high substrate specificity, and an action pattern of the endo-type. 相似文献
86.
Shiro Ohki Yoshimasa Nishigaki Katsuhiro Imaki Masayasu Kurono Fumio Hirata Toshio Hanyu Nobuhiko Nakazawa 《Prostaglandins & other lipid mediators》1976,12(2):181-186
Radioimmunoassay technique for measuring 5α,7α-dihydroxy-11-keto-tetranorprosta-1,16-dioic acid, the main urinary metabolite of PGF1α and PGF2α (PGF2α-MUM), was further improved.It was postulated based on some experimental data that the PGF2α-MUM exists in the urine mostly as dioic acid form, not as δ-lactone formThe daily excretion of PGF2α-MUM in men ranged from 14.43 μg to 36.14 μg and in women from 5.21 μg to 14.25 μg. 相似文献
87.
Keishi Abe Yoichi Otsuka Minoru Yasujima Satoru Ciba Masahide Seino Nobuo Irokawa Kaoru Yoshinaga Fumio Hirata Shiro Ohki Nobuhiko Nakazawa Toshio Hanyu 《Prostaglandins & other lipid mediators》1976,12(5):843-848
The excretion rates of main urinary metabolite of PG F2α were measured radioimmunologically in 4 healthy persons and in 13 essential hypertensives. The resting values were 9.3±0.73 in the former and 10.4±2.17 ng/min in the latter. There was no significant differences between them. The excretion of the metabolite decresed prominently after the administration of furosemide. The percent decrease was 57% in healthy persons and 70% in essential hypertension. The percent result supports that furosemide inhibit the catabolism of PG F2α. 相似文献
88.
The occurrence of a factor in soybean which deters feeding of the silkworm was demonstrated. The deterrent was not extractable with ether or ethanol, but was extracted with 90% ethanol or hot water. Preliminary experiments showed that the deterrent was adsorbed on charcoal, but neither on activated alumina nor in a steam distillate. Autoclaving did not inactivate the deleterious effect. A crude extract of the deterrent showed a marked negative feeding response by including 0·4 mg/g of the dry diet.Inclusion of the crude extract in the diet retarded the growth of larvae, whereas larvae grew well when receiving the 90% ethanol-washed meal. Feeding response for various soybean meals and proteins were compared, and better larval growth has generally obtained when the feeding response was more positive. It is, however, inconclusive whether or not the deleterious principle possesses some physiologically toxic effect.The feeding behaviour of newly hatched larvae was observed in the presence of favourable and/or unfavourable diets, and a brief discussion is made concerning the feeding behaviour of this insect. 相似文献
89.
Toshio Miyazaki Toshiro Yadomae Takayoshi Terui Haruki Yamada Terukichi Kikuchi 《Biochimica et Biophysica Acta (BBA)/General Subjects》1975,385(2)
A water-soluble glucuronan “protuberic acid”, [α]d22 −83.6° and purified from Kobayashia Nipponica, and its physicochemical properties were investigated.The purified protuberic acid was homogeneous as shown by zone electrophoresis, gel filtration over Sepharose 4B, and ultracentrifugation. The sedimentation coefficient was 1.8 S and its intrinsic viscosity was 1.1 dl/g. By gel filtration the molecular weight was estimated to be about 170 000. The results of periodate oxidation, methylation analysis, and partial acid hydrolysis indicated that this acidic polysaccharide has a linear structure of mainly 1,4-linkages and containing an acid-labile linkage. Reduced protuberic acid, [α]d22 −44°, is also described. 相似文献
90.