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131.
Clr was isolated from human serum by DEAE-cellulose column chromatography in the presence of EDTA. The isolated Clr did not hydrolyze N(alpha)-acetyl-L-arginine methyl ester, unless activated by brief treatment with trypsin [EC 3.4.21.4]. On thecolumn, the C1 esterase inhibitor activity was found to coincide with Clr but not C1s (another subcomponent of the first component) C1r was isolated from the euglobulin fraction of human serum by DEAE-cellulose column chromatograph. On Sephadex G-200 column chromatography, Clr was eluted in the void volume, whereas Clr was eluted in a position corresponding to a molecular weight of 140,000-160,000. The results indicated that, on activation, Clr was converted to an enzyme of lower molecular weight... 相似文献
132.
A new pentacyclic triterpene acid was isolated from the arial parts of Salvia virgata and its constitution was established as 3β-hydroxy-1-oxo-olean-12-en-28-oic acid and named virgatic acid. 相似文献
133.
134.
Removal of proteases from DNase I by chromatography over agarose with covalently attached lima bean protease inhibitor 总被引:4,自引:0,他引:4
Lima bean protease inhibitor (LBI) can be convalently attached to agarose using the cyanogen bromide activation procedure. The LBI-agarose complex retains full capacity to inhibit chymotrypsin and 30% capacity to inhibit trypsin; the dissociation constant for chymotrypsin bound to LBI-agarose is 3.7 × 10?6m. Bovine pancreatic deoxyribonuclease is contaminated by 3% by weight of chymotrypsin plus chymotrypsinogen. The contaminating proteases may be removed from DNase by sequential reaction with LBI-agarose followed by filtration. The most effective method for the removal of proteases from DNase is chromatography over LBI-agarose. DNase which has been chromatographed over LBI-agarose is at least ten times more stable than DNase prepared by earlier procedures. 相似文献
135.
The toxic effect of spermidine on normal and transformed cells 总被引:2,自引:0,他引:2
H Otsuka 《Journal of cell science》1971,9(1):71-84
136.
MEASUREMENT OF γ-AMINOBUTYRIC ACID IN ISOLATED NERVE CELLS OF CAT CENTRAL NERVOUS SYSTEM 总被引:6,自引:3,他引:3
Abstract— A sensitive method for measuring γ-aminobutyric acid (GABA) has been developed. This method consists of a combination of the enzymic GABA assay of J akoby and S cott (1959) with the enzymic cycling technique of L owry , P assonneau , S chulz and R ock (1961) and permits the measurement of as little as 2 × 10−14 mol of GABA. Using this method, GABA analyses were made on single isolated nerve cell bodies of different types from the CNS of the cat. Average GABA concentrations in these cell bodies were: spinal ganglion cells, 0.2 m m ; spinal mononeurons, 0.9 m m ; large cells of the ventral part of Deiters' nucleus, 2.7 m m ; large cells of the dorsal part of Deiters' nucleus, 6.3 m m ; cerebellar nuclei cells, 6.0 m m ; cerebellar Purkinje cells, 6.6mM; cerebral Betz cells, 2.5 m m .
The GABA concentrations in the isolated dorsal Deiters' cells were greatly reduced (1.7 m m ) after the removal of the cerebellar vermis while those of the ventral Deiters' cells were unaffected by the denervation. These results suggest that GABA is concentrated within axon terminals, probably of Purkinje neurons, synapsing with the dorsal Deiters' cells. The results of GABA analyses on isolated nerve cells are discussed in relation to the relevant neuronal functions and the possible role of GABA as an inhibitory transmitter. 相似文献
The GABA concentrations in the isolated dorsal Deiters' cells were greatly reduced (1.7 m m ) after the removal of the cerebellar vermis while those of the ventral Deiters' cells were unaffected by the denervation. These results suggest that GABA is concentrated within axon terminals, probably of Purkinje neurons, synapsing with the dorsal Deiters' cells. The results of GABA analyses on isolated nerve cells are discussed in relation to the relevant neuronal functions and the possible role of GABA as an inhibitory transmitter. 相似文献
137.
138.
From a MeOH extract of leaves of Grevillea robusta, seven compounds (1-7) were isolated. One known compound (7) was identified with a benzyl glucoside, icariside F2. The structures of the six of these, named grevillosides A-F (1-6), were elucidated on detailed inspection of one- and two-dimensional NMR spectroscopic data as glucosides of 5-alkylresorcinols. 相似文献
139.
At the present stage, many papers on MEKC, which include fundamental characteristics and applications, have been available. Because only brief discussion on some aspects of MEKC was described in this article, it is necessary to refer some of those literature when the detailed information is required. Especially, for optimization strategies of MEKC, which was not discussed in this article, theoretical discussions by Foley(85), Vindevogel and Sandra(86), and Khaledi and coworkers(87,88) should be cited, along with the review article(11). 相似文献
140.