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71.
Howard R. Morris Karen E. Batley Nigel G. L. Harding Richard A. Bjur John G. Dann Rodney W. King 《The Biochemical journal》1974,137(2):409-411
An elastase digest of a protein of unknown structure, dihydrofolate reductase, was studied by mass spectrometry. This soluble digest contained a large number of small peptides in different yields, within the ideal molecular-weight range (200-1200) for mixture-analysis mass spectrometry. Sequences of the major component peptides in the digest are reported. 相似文献
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73.
Cerebral cortical ATP, P-creatine, glucose, and lactate were measured 6 sec after 1 sec of 150/sec rectangular pulses, at 0,20 v, 40 v, 60 v, 80 v, or 100 v, applied to the heads of intact mice which had been given either no drug, phenobarbitone (25 mg/kg), trimethadione (600 mg/kg), or diphenylhydantoin (40 mg/kg), intraperitoneally. In general, regardless of stimulus strength or drug used, animals which exhibited maximal (tonic-clonic) convulsions showed similar striking decreases in brain P-creatine, decreases in ATP and glucose, and increases in lactate. On the other hand, in animals which exhibited less than maximal clinical response, there was little or no change in these metabolites. An exception was the case of diphenylhydantoin. Tonic-clonic seizures did not occur after diphenylhydantoin administration, even with 100 v stimuli, but substrate changes at this voltage were, nevertheless, similar to those observed in brains of other mice undergoing maximal convulsions. 相似文献
74.
75.
The structure and possible mode of functioning of the female reproductive system in Nasonia vitripennis (Hymenoptera: Pteromalidae) 总被引:1,自引:0,他引:1
Associated with the female insect reproductive system are a number of glands. Those present in Nasonia vitripennis are described, their microanatomy examined and where possible this is linked with their function during the process of drilling into the host puparium, feeding on the host fluids and oviposition. The structures dealt with are the ovaries, spermatheca, alkaline gland, colleterial gland and the acid gland with reservoir. 相似文献
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77.
N. J. King 《The Biochemical journal》1966,100(3):784-792
1. The extracellular enzymes present in the culture filtrates of Coniophora cerebella grown on various carbohydrate carbon sources were investigated. Enzymes that degraded cellulose derivatives, hemicellulose fractions, starch, laminarin, pectin and several oligosaccharides were detected. 2. All the polysaccharide-degrading activities were adaptive except for that acting on laminarin. 3. The culture filtrates degraded native cellulose to only a very limited extent. 4. The hemicellulase activity included enzymes acting on all the major components of wood hemicellulose. 5. The main starch-degrading enzyme was a glucoamylase. 6. Laminarin-degrading activity was produced when cellulose, hemicellulose or starch was used as carbon source for the fungus and it may be involved in the re-utilization of hyphal carbon or of a reserve polysaccharide synthesized during active growth of the organism. 相似文献
78.
The metabolism of [2-14C]indole in the rat 总被引:3,自引:1,他引:2
1. [2-14C]Indole has been synthesized from [14C]formate and o-toluidine via N[14C]-formyltoluidine. 2. When fed to rats, the 14C of [14C]indole (dose 70–80mg./kg. body wt.) is fairly rapidly excreted, and in 2 days an average of 81% appears in the urine, 11% in the faeces and 2·4% as carbon dioxide in the expired air. 3. Radioactivity is excreted in the urine as indoxyl sulphate (50% of the dose), indoxyl glucuronide (11%), oxindole (1·4%), isatin (5·8%), 5-hydroxyoxindole conjugates (3·1%), N-formylanthranilic acid (0·5%) and unchanged indole (0·07%). The faeces contain indoxyl sulphate (0·4% of the dose) and indole (0·2%), but the major metabolites have not been identified. 4. Fed to rats with biliary cannulae an average of 5·6% of a dose of [14C]indole (20–60mg./kg. body wt.) is excreted in the bile in 2 days. Radioactivity is present as indoxyl sulphate (0·8% dose) and 5-hydroxyoxindole conjugates (0·6%). 5. Rats further metabolize indoxyl into N-formylanthranilic acid and anthranilic acid, and oxindole into 5-hydroxyoxindole. 6. With rat-liver microsomes plus supernatant under aerobic conditions, indole gives indoxyl, oxindole, possibly isatin, N-formylanthranilic acid and anthranilic acid, but under anaerobic conditions gives only oxindole. Similarly, under aerobic conditions, oxindole gives 5-hydroxyoxindole, anthranilic acid and o-aminophenylacetic acid. 7. Indole is metabolized by two pathways, one via indoxyl to isatin, N-formylanthranilic acid and anthranilic acid, and the other via oxindole to 5-hydroxyoxindole and possibly to o-aminophenylacetic and anthranilic acid. 8. The following new compounds are described: 4-hydroxy-2-nitrophenylacetic acid, 3-, 4- and 5-benzyloxy-2-nitrophenylacetic acid, 5- and 7-hydroxyoxindole and 5-aminoacridine indoxyl sulphate. 相似文献
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80.