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161.
162.
Micromorphology of Cryptococcus neoformans 总被引:10,自引:3,他引:7
Mercedes R. Edwards Morris A. Gordon Edward W. Lapa William C. Ghiorse 《Journal of bacteriology》1967,94(3):766-777
Fine details of the internal and external morphology of Cryptococcus neoformans as seen in ultrathin sections are described and illustrated with electron micrographs. The capsule characteristic of this species contained microfibrils (30 to 40 A in diameter) that appeared to radiate from the cell wall and to coil and intertwine in various directions. These thin, uniformly structured, electron-dense filaments are believed to represent complex polysaccharide molecules. The internal morphology of C. neoformans was in many ways similar to that of yeasts studied by other authors. The cell was uninucleate with a single nucleolus. The nuclear envelope, a pair of unit membranes interrupted by pores, was typical of that found in eucaryotic organisms. Smooth endoplasmic reticulum, mitochondria, vacuoles, storage granules, and ribosomes were consistent features of the cytoplasm. In addition, C. neoformans presented membranous organelles derived from the plasma membrane and comparable to bacterial mesosomes and mitochondria of an annulate type. 相似文献
163.
Gordon H. Snow 《The Western journal of medicine》1964,101(4):260-262
The term “whiplash,” used to describe a neck injury received in an automobile accident, has no foundation in medical science to support the complaints of persons suing for damages. The term is gaining unwarranted popularity as a term describing an injury, even though there are no clinical or pathological findings to support it.“Whiplash” cases today account for an estimated 30 per cent of all injuries in automobile accidents. Direct compensation for damages paid to persons injured in automobile accidents in the United States in 1961 amounted to approximately one billion, seven hundred million dollars. It has been estimated that five hundred and eighty million dollars of that amount was paid in compensation on allegation of neck injuries. 相似文献
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166.
Gordon J. Sproul 《The Western journal of medicine》1967,106(4):327-330
• Figures on professional registered nurses recently made available indicate that the ratio of active nurses to population in California in 1962 was 327 per 100,000 persons. The comparable figure nationally was 298/100,000. California ranked twentieth out of the 50 states and the District of Columbia.The percentage of all nurses actively engaged in nursing is considerably lower in California than in the total United States: 60.4 per cent compared with 65.3 per cent. This indicates that the shortage of nurses in California is more attributable to underutilization of potential manpower than to its absence.There are some identifiable categories of nurses in California in which the utilization of personnel is particularly low, as compared with other states. In terms of rates of utilization, the group of nurses over 60 years of age are most noticeably under-utilized, while in terms of numbers, married nurses could provide the greatest supply of extra nurses were their employment rate in the state equal to the national rate.The recruiting potential is a very great one, however, as this report indicates. 相似文献
167.
Interferon Production in Mice by Cell Wall Mutants of Salmonella typhimurium 总被引:3,自引:0,他引:3
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The interferon response elicited by Salmonella typhimurium mutants in mice is not dependent on the presence of a complete cell wall lipopolysaccharide. In fact, a mutant (G30/C21) which has lost all the polysaccharide side chains and sugars of the O antigen and contains only 2-keto-3-deoxyoctonate and lipid is indistinguishable in its interferon-stimulating ability from the wild type which possesses a complete O antigen with polysaccharide side chains. 相似文献
168.
From a stock of varkappa phage grown on Salmonella, a host-range mutant which attacks Escherichia coli was isolated. As in the case of Salmonella, only motile strains of E. coli are sensitive to varkappa. The phage shows an eclipse period of 35 min and a minimal latent period of 52 min. The adsorption rate constant is 3 x 10(-9) ml/min. Adsorption shows a marked dependence on temperature. Bacteriophage varkappa was purified by differential centrifugation and CsCl density gradient centrifugation. It contains deoxyribonucleic acid (DNA) which is double-stranded. The DNA has a molecular weight of 42 million and a guanine plus cytosine content of 57%. Of 68 molecules of DNA inspected, 7 were circular. The phage particle weight is about 90 million. 相似文献
169.
During competitive water polo, heart rate in six subjects was monitored by cupped plastic and silver electrodes glued to the skin. Minimum rates during the game averaged 156 beats/min.; maximum rates averaged 186 beats/min. Mean maximum rate with bicycle exercise was 188 beats/min. Maximum oxygen (VO2 max.) with bicycle exercise of 14 water-polo players was 53.3 ml./kg. Physical working capacity (PWC 170) was 1310 kilopond metres per square metre (k.p.m./sq.m.). PWC 170 correlated well with VO2 max. in this small group (r = 0.77).Oxygen uptake was measured at three speeds of swimming and four levels of work on a bicycle ergometer. VO2 max. of swimming was 88% of that obtained on bicycle exercise. The slope of the oxygen uptake vs. pulse rate curves was less for the swimming than for cycling, so that for a given oxygen uptake below the maximal, pulse rate was less in the swimmers. At near-maximal swimming, respiratory quotient was 0.95 compared with 1.27 for cycling, suggesting that the swimmers were underbreathing. 相似文献
170.