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181.
182.
Lysogenic Conversion in Bacillus amyloliquefaciens H Affecting Viral Adsorption 总被引:3,自引:2,他引:1 下载免费PDF全文
Lysogenization of Bacillus amyloliquefaciens H with bacteriophage PK renders the bacteria resistant to superinfection with bacteriophage of PK type. 相似文献
183.
Detection and localization of antibody-forming cells to a bacterial endotoxin by an immunobioautographic procedure 总被引:1,自引:0,他引:1
184.
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186.
Simultaneous assay of insulin and glucagon in serum 总被引:2,自引:0,他引:2
187.
Can the distribution of inspired gas be altered? 总被引:2,自引:0,他引:2
188.
E. D. Young 《Bulletin of mathematical biology》1968,30(3):359-385
The arterial system is characterized geometrically as a system of branched elastic fluid lines whose frequency response is
then known in the sense of the Fourier transform. For convenience of visualization the transient response of the individual
tube to an input pressure-flow pair is represented in the time domain by kernel functions indicating the hybrid effect of
viscosity and momentum on the line impedance and damping characteristics. The system as a whole is then divided into a zone
of smaller tubes (below 3 mm) and a zone of larger tubes extending up to the aorta. It is shown that as a system each labyrinth
of tubes below the 3 mm size may be replaced by a single impedance transformation which is dominantly resistive-capacitive.
In the larger tubes, the transformation of the pulse wave at different stations is considered a point of interest. Therefore
hand calculated examples are worked to derive the response of a system involving some of the larger vessels to a pressure
or flow pulse of the typical shape seen near the heart. The result suggests that the dicrotic wave seen in the pressure pulse
of mammals is due to the hybrid viscosity-momentum nature of the longer fluid lines in relation to the gradation of unmatched
terminal impedances with which they are terminated. Damping of the higher frequency components is also accounted for. 相似文献
189.
Ruth C. Steinkamp Clarence L. Young Dolores Nyhus Arnold E. Greenberg 《The Western journal of medicine》1968,109(2):126-133
The amount of sodium ion in water used for ingestion may be critical in effective use of a low sodium dietary regimen. Waters containing not over 20 mg of sodium per liter are provided for in the sodium restricted diets set forth by the American Heart Association. For diets containing more than 500 mg of sodium a day, waters of greater sodium content may be used if proper dietary adjustments are made.While assessment of the long-term average sodium content of a community water supply is difficult, the determined values for sodium lend to classification within range categories. The larger community water supplies in California are presented within several range categories of sodium content.The more commonly used water softeners add sodium to water. The sodium-restricted patient should be cautioned against their use. Similar consideration should probably be given to water supplies of retirement communities where the potential for disorders requiring sodium restriction is greater than in the general population. 相似文献
190.
Byron S. Tepper 《Journal of bacteriology》1968,95(5):1713-1717
A basic difference was found in the kinetics of uptake and utilization of glucose and glycerol by washed suspensions of Mycobacterium phlei. With glucose, the rates of uptake, respiration, and assimilation were saturated at low external substrate concentration. With glycerol, these rates were found to increase with increasing substrate concentration and did not show saturation at any concentration tested. Qualitatively similar patterns were observed for cells grown on either glycerol or glucose. Above a saturation concentration, ratios of cell (14)C to CO(2) (14)C for uniformly labeled (14)C-glucose were constant at a value of 0.96. Glycerol-U-(14)C, on the other hand, yielded cell-(14)C/CO(2)-(14)C ratios which were highest at the lowest glycerol concentration tested, and decreased with increasing substrate concentration. The distribution of the glucose and glycerol carbons assimilated into M. phlei were qualitatively similar. Quantitatively, however, the uptake and assimilation of glycerol was far more rapid than that of glucose for all substrate concentrations employed. These quantitative differences in the utilization of glycerol and glucose could account for the increased content of nonessential lipid and polysaccharide found in glycerol-grown M. phlei. 相似文献