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Arthur Leznoff Harold Frank Paul Telner Jacob Rosensweig J. Leonard Brandt 《CMAJ》1964,91(22):1154-1160
Although Montreal is in an endemic area, significant clinical histoplasmosis with systemic manifestations has been, until recently, infrequently diagnosed. However, since the autumn of 1963, 31 cases of clinically significant histoplasmosis have been seen by the authors. These were divided into two groups: (1) patients in whom the diagnosis was established on the basis of histological and/or cultural demonstration of the fungus; (2) patients in whom the diagnosis was based on a positive histoplasmin skin test, a complement fixation antibody titre of 1:32 or greater and compatible clinical and radiological findings. An additional group of 11 patients who presented with erythema multiforme was investigated and a heretofore unrecognized relationship between histoplasmosis and erythema multiforme was established. 相似文献
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A versatile and simple continuous-culture apparatus is described. With this apparatus, independent control of limiting growth factors and other nutrilites is possible and the conditions of each experiment are reproducible. In view of the synchronized speed of the feeder syringes, flow variation troubles are not encountered. The device allows the performance of growth experiments at different dilution rates simultaneously in a single run which makes the comparison of the results more reliable. The operation of the device has been tested successfully with a study of adenine deaminase induction in yeast. 相似文献
247.
C. A. Gibson G. B. Landerkin Pamela M. Morse 《Applied and environmental microbiology》1966,14(4):665-669
Three single-strain cultures, Streptococcus lactis C2, S. cremoris R1, and S. diacetilactis DRC2, were frozen and stored in skim milk, in skim milk containing apple juice, and in skim milk containing one of the following additives: glycerol (10%, v/v), dimethyl sulfoxide (10%, v/v), l-malic acid (0.5 and 2.0%, w/v), acetamide (0.5 and 2.0%, w/v), or succinimide (0.5 and 2.0%, w/v). Cultures were frozen and stored at -23.3 C, frozen and stored at -196 C in liquid nitrogen, or frozen at -196 C and stored at -23.3 C. Cultures frozen and stored at -196 C in liquid nitrogen gave the greatest recovery of viable cells. The number of cells surviving after storage at -23.3 C was greater when the cells had been frozen in liquid N2 than when they had been frozen at -23.3 C. All strains stored at -23.3 C showed a decrease in numbers of surviving cells; additives, particularly l-malic acid and apple juice, were advantageous in preserving the viability of the S. lactis C2 and S. cremoris R1 strains, but had little or no effect on the survival of S. diacetilactis DRC2. l-Malic acid and apple juice stimulated acid production for all cultures in activity tests following incubation after thawing, whereas glycerol and dimethyl sulfoxide retarded its development. 相似文献
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