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21.
Chardonnet Yvette Viac Jacqueline Levai Jacques Begoud Gérard Morgon Alain Thivolet Jean 《Virchows Archiv. B, Cell pathology including molecular pathology》1986,51(1):421-428
Virchows Archiv B Cell Pathology - Various parameters of the local cellular response have been studied in 16 laryngeal papillomas from ten patients with recurrent papillomas as well as normal... 相似文献
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Differential Tolerance of Streptomycetes to Sodium Chloride as a Taxonomic Aid 总被引:2,自引:1,他引:1 下载免费PDF全文
A survey was made of the NaCl tolerance of approximately 1,300 Streptomyces strains belonging to 313 species. The growth medium of the organisms was supplemented with a graded series of NaCl concentrations (4, 7, 10, and 13%). Only 1.8% of the species could not tolerate 4% NaCl; 26.9% could grow at a maximum of 4%; 49.7% could tolerate a maximum of 7%; 18.8% could grow at a maximum of 10%; and only 2.8% could tolerate 13% NaCl. In evaluating the relationships of NaCl tolerance to various taxonomic features, higher tolerance was statistically associated with the "yellow" and possibly the "white"-spored streptomycetes, whereas the "red"-spored series tended to have lesser tolerance. Higher tolerance was also indicated for spiny-spored species, as a group, than for smooth-spored forms. Likewise, nonproducers of melanin, collectively, were more NaCl tolerant than melanin-producing species. Uniformity of test responses between strains of species studied suggested the usefulness of NaCl tolerance as a taxonomic criterion. 相似文献
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Coxsackie A9 virus was identified by the authors during the fall of 1965 in Montreal in six children with fever and exanthem. Three of the six children were siblings. The exanthem was centrally distributed as described by Lerner et al. and consisted of discrete maculopapules 3 to 4 mm. in diameter. The viral agent was recovered and identified in tissue culture in five cases, while in the sixth Coxsackie type-A lesions were produced in suckling mice. Serological confirmation was obtained in two patients from whom sera were available. In contrast, no exanthem was observed in three older patients with a diagnosis of aseptic meningitis associated with Coxsackie A9 virus. In only one of 16 patients with Coxsackie B virus infection was an exanthem observed during the same period.The true incidence of Coxsackie A9-associated exanthems is difficult to determine because of the benign nature of the disease. 相似文献
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Judy L. Jakobek Jean C. Stutz Vicki H. Bess Ralph A. Backhaus 《Plant Cell, Tissue and Organ Culture》1993,35(3):297-299
Both Cowania subintegra Kearney and C. stansburiana Torr. were successfully propagated in vitro. Shoot proliferation occurred from shoot tips of green-house grown C. subintegra using a modified Murashige and Skoog medium supplemented with 4.4 M 6-benzyladenine and 0.5 M indole butyric acid. Excised microshoots (1.5–3.0 cm long) of both species were rooted using a two-step process in which they were cultured for 3 days in a root initiation medium with 2.7 M naphthaleneacetic acid and then transferred to a low nitrogen root elongation medium without auxin. Plantlets were successfully transferred to soilless potting mix. 相似文献
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Although semi-free-ranging Barbary macaque females are able to outrank older females from lower-ranking matrilines (matrilineal rank acquisition), they do not systematically outrank their older sisters, as is known to be the case for semi-free-ranging rhesus monkeys (Macaca mulatta) and Japanese macaques (Macaca fuscata). We test the hypothesis that differences in the support received by younger sisters against their older sisters and against older lower-ranking females might account for this interspecific difference. Thirty-one sister dyads, members of a group of 109 Barbary macaques living at La Montagne des Singes, France, were observed during 16 months. The results indicate that (1) all females were dominant to their younger sisters, and the latter were never observed to challenge their older sisters; (2) younger sisters received as much kin support against their older sisters as against older lower-ranking females; (3) only very young females received support from their kin against their older sisters; (4) younger sisters received much more support from nonkin females against lower-ranking females than against their older sisters; and (5) Barbary macaque females appear to be supported against their older sisters less frequently than rhesus macaque females are. We conclude that the lack of nonkin support is the main factor accounting for the failure of younger sisters to outrank their older sisters in Barbary macaques. Initially this might result from kin support not being sufficient to induce younger sisters to challenge and to solicit support against their older sisters. 相似文献