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91.
C J King 《Cryobiology》1974,11(2):121-126
Certain gases, when dissolved at high pressure in foods and biological materials, give a structure of gas bubbles inflating cells after freezing, depressurization, and thawing. This phenomenon has been found to reduce shrinkage after subsequent drying. The effect is interpreted quantitatively in terms of the needs for (a) a sufficient solubility of the gas in the water of the tissue at high pressure so that the Bunsen coefficient is high enough (at least 1.5 cm3/cm3 for maximum effect), and (b) a sufficiently low permeability, expressed as the product of atmospheric solubility and diffusivity in water (equal to or less that of air for maximum effect). 相似文献
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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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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
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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
99.
Generic Identification of L-Forms by Polyacrylamide Gel Electrophoretic Comparison of Extracts from Parent Strains and Their Derived L-Forms 总被引:3,自引:1,他引:2 下载免费PDF全文
A polyacrylamide gel electrophoretic method was used for identification of L-forms in the genera Streptococcus, Staphylococcus, and Proteus, by comparing phenol-acetic acid-water extracts of homologous parent L-form pairs to one another and to other pairs. The method requires only milligram quantities of material for analysis. The standard patterns for the strains used in this study are shown as pictures of the gels and as densitometric tracings of appropriate gels. They show that, despite occasional minor differences in some organisms, the gel electrophoretic patterns of homologous L-forms and bacterial pairs are sufficiently similar-as well as sufficiently dissimilar from patterns of other genera-to permit generic identification of an unknown L-form by reference to patterns derived from possible parental bacteria. 相似文献
100.