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111.
Dr. Paul Schwarze 《Planta》1960,55(6):630-636
Ohne ZusammenfassungMit 3 Textabbildungen 相似文献
112.
A modification of the agar-gel precipitation inhibition technique of Thorne and Belton for detecting anthrax antibodies reduces inconsistency of visually determined end points on the same sera observed by different technicians. Determination of the minimal reacting concentrations of the anthrax antigen and antibody reagents, modifications of the visualization apparatus, methods for combining reagents, and length of incubation periods contribute to the ease of the end-point determinations and the uniformity of results. When compared with the previous technique, the modified procedure is less time-consuming while retaining satisfactory reproducibility, simplicity, specificity, and sensitivity. 相似文献
113.
Comparison of Direct Plating Media for the Isolation and Enumeration of Enterococci in Certain Frozen Foods 总被引:4,自引:1,他引:3 下载免费PDF全文
A total of 15 agar media were examined for their yield, selectivity, readability, and simplicity of preparation and use. A thallium medium of Barnes was selected as the better of the high yield-fair selectivity type of medium and an azide-citrate medium of Reinbold appeared to be the better of the low yield-high selectivity type of medium. Sodium carbonate (optimal concentration, 0.20%) was found to increase recovery substantially when added to certain media, especially in the presence of 0.05% Tween 80. When these two ingredients were incorporated into a medium modified after Slanetz and Bartley, the resultant medium was superior to other media for the isolation and enumeration of enterococci in certain frozen foods, such as peas and hamburger, by the direct plating method. 相似文献
114.
FREE NUCLEOTIDES OF THE BRAIN IN VARIOUS MAMMALS 总被引:4,自引:0,他引:4
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Paul G. Arnison Pauline Donaldson Anne Jackson Charmaine Semple Wilf Keller 《Plant Cell, Tissue and Organ Culture》1990,20(3):217-222
Anther culture medium was prepared with different types and concentrations of cytokinins to gain greater insight into the control of embryo formation during Brassica oleracea L. var. italica (broccoli) anther culture. The independent addition of the four cytokinins tested had widely divergent effects dependent upon cytokinin concentration and the genetic background of the test plants. All cytokinins were generally inhibitory at high concentrations, however, individual plants showed significant stimulation of embyro formation at typical physiological levels. The influence of cytokinins was highly cultivar-specific, some lines were stimulated, others inhibited and still other test lines were largely unaffected. Although the addition of cytokinins was needed for embryo formation for some plants, in no instance were cytokinins able to replace the inductive effect of high-temperature treatments. 相似文献