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71.
Chemical Nature of Malty Flavor and Aroma Produced by Streptococcus lactis var. maltigenes 下载免费PDF全文
Mature skim milk cultures of Streptococcus lactis var. maltigenes were steam distilled at low temperature under reduced pressure. Ethyl ether extracts were prepared from the distillates and analyzed by gas-liquid chromatography and mass spectrometry. Twenty of 31 components detected in the culture distillates were identified positively and 11 tentatively, whereas 10 of 19 components detected in the heated skim milk control were identified positively and 9 tentatively. Among components detected in the culture distillate, but not detected in the heated skim milk distillate, and which have not been previously identified in milk cultures of the organism were phenylacetaldehyde and phenethanol. Quantitative analyses of the volatiles entrained from milk cultures of several strains of S. lactis var. maltigenes revealed a probable relationship between variation in the character of the aroma of the cultures and the alcohol/aldehyde ratio. 相似文献
72.
Isolation of brain tubulin by affinity chromatography 总被引:2,自引:0,他引:2
N D Hinman J L Morgan N W Seeds J R Cann 《Biochemical and biophysical research communications》1973,52(3):752-758
An affinity chromatographic procedure for the isolation of tubulin from brain is described. The yield is good and the method rapid and gentle. Criteria of purity are colchicine binding, SDS acrylamide gel electrophoresis, and velocity sedimentation. 相似文献
73.
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75.
Structure and Development of Viruses as Observed in the Electron Microscope: X. Entry and Uncoating of Adenovirus 总被引:1,自引:1,他引:0 下载免费PDF全文
Stages in the direct penetration of adenovirus through the cell membrane are illustrated. Phagocytosis with rupture of the vacuole and release of virus into the cytoplasm may also account for entry of some particles. Uncoating by digestion within phagosomes was not observed. Rather, alteration of capsid and core occurred to virions free in the cytoplasm. Nucleoprotein released from virus close to the nucleus was transported to the nuclear matrix by a unique mechanism. These events were not prevented by puromycin and hence were not dependent upon the synthesis of new enzymes. They were, however, energy-dependent. 相似文献
76.
Stimulation of ethylene evolution and abscission in cotton by 2-chloroethanephosphonic Acid 总被引:14,自引:13,他引:1 下载免费PDF全文
Morgan PW 《Plant physiology》1969,44(3):337-341
Ethrel, a mixture of 2-chloroethanephosphonic acid and its ethyl ester, hastens abscission of leaves, debladed petioles, and flower buds of cotton plants (Gossypium hirsutum, L.). Both young and old leaves abscissed while still green. Application of Ethrel stimulated evolution of ethylene, and this response preceded abscission. Air concentrations of ethylene around enclosed, treated-plants were adequate to produce abscission in plants. Non-treated plants defoliated when enclosed with plants sprayed with Ethrel. The stimulation of abscission of explant petioles by Ethrel was reversed by naphthalene acetic acid. The stimulation of abscission by Ethrel was concluded to be mediated by ethylene. 相似文献
77.
Ten adults suffering from salicylate overdosage were treated successfully with a combination of sodium bicarbonate and acetazolamide to exploit the increase in salicylate clearance which is known to occur in very alkaline urine. The advantages of the method include the absence of important complications and the small volume of fluid required. 相似文献
78.
Isolation of microfilaments from Amoeba proteus 总被引:2,自引:0,他引:2
79.
THE EFFECT OF INSULIN, ALLOXAN DIABETES, AND ANOXIA ON THE ULTRASTRUCTURE OF THE RAT HEART 总被引:3,自引:1,他引:2 下载免费PDF全文
Hearts from normal and alloxan diabetic rats were perfused in vitro with a bicarbonate-buffered medium containing glucose. Transport of glucose through the cell membrane was stimulated with insulin or by induction of anaerobiosis. The organs were rapidly fixed and examined by electron microscopy. Transport stimulation was not associated with any increase in the number of sarcolemmal invaginations or subsarcolemmal cytoplasmic vesicles. It was concluded that glucose transport and the effects of insulin or anoxia do not involve pinocytosis. The relationship of pinocytosis to glucose transport is discussed. The appearance of numerous lipid inclusions at the Z line level of the sarcomeres in the diabetic and anoxic myocardia is described. 相似文献
80.