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991.
Fanconi H. Hamperl H. Ehrhart W. Lang H. Otto A. Hässig Ludwig Heilmeyer N. Matussek R. Marx R. Haas Talmage D. Ploog Strian W. Lang J. Eisenburg Lang Ludwig Heilmeyer H. Neubauer Walter Hartenbach A. Blumberg 《Journal of molecular medicine (Berlin, Germany)》1967,45(5):270-274
Ohne Zusammenfassung 相似文献
992.
993.
Global control in Pseudomonas fluorescens mediating antibiotic synthesis and suppression of black root rot of tobacco. 总被引:14,自引:2,他引:12 下载免费PDF全文
J Laville C Voisard C Keel M Maurhofer G Défago D Haas 《Proceedings of the National Academy of Sciences of the United States of America》1992,89(5):1562-1566
Pseudomonas fluorescens CHA0 colonizes plant roots, produces several secondary metabolites in stationary growth phase, and suppresses a number of plant diseases, including Thielaviopsis basicola-induced black root rot of tobacco. We discovered that mutations in a P. fluorescens gene named gacA (for global antibiotic and cyanide control) pleiotropically block the production of the secondary metabolites 2,4-diacetylphloroglucinol (Phl), HCN, and pyoluteorin. The gacA mutants of strain CHA0 have a drastically reduced ability to suppress black root rot under gnotobiotic conditions, supporting the previous observations that the antibiotic Phl and HCN individually contribute to the suppression of black root rot. The gacA gene is directly followed by a uvrC gene. Double gacA-uvrC mutations render P. fluorescens sensitive to UV irradiation. The gacA-uvrC cluster is homologous to the orf-2 (= uvrY)-uvrC operon of Escherichia coli. The gacA gene specifies a trans-active 24-kDa protein. Sequence data indicate that the GacA protein is a response regulator in the FixJ/DegU family of two-component regulatory systems. Expression of the gacA gene itself was increased in stationary phase. We propose that GacA, perhaps activated by conditions of restricted growth, functions as a global regulator of secondary metabolism in P. fluorescens. 相似文献
994.
995.
A total of 166 surgical blades consisting of control blades, skin blades, and deep blades were cultured from 50 elective podiatric surgical cases. Five blades from four cases cultured Staphylococcus epidermidis. The practice of changing from skin blade to deep blade to reduce contamination of a clean surgical wound is not supported by the data obtained in this study. 相似文献
996.
J. R. Hully Y. Su J. K. Lohse A. E. Griep C. A. Sattler M. J. Haas Y. Dragan J. Peterson M. Neveu H. C. Pitot 《The American journal of pathology》1994,145(2):386-397
Although transgenic hepatocarcinogenesis has been accomplished in the mouse with a number of genetic constructs targeting the oncogene to expression primarily in the liver, no example of this process has yet been developed in the rat. Because our understanding of the multistage nature of hepatocarcinogenesis is most advanced in the rat, we have developed a strain of transgenic rats carrying the promoter-enhancer sequences of the mouse albumin gene linked 5' to the simian virus-40 T antigen gene. A line of transgenic rats bearing this transgene has been developed from a single founder female. Five to six copies of the transgene, possibly in tandem, occur within the genome of the transgenic animals, which are maintained by heterozygous matings. Livers of transgenic animals are histologically normal after weaning; at 2 months of age, small foci of vacuolated cells appear in this organ. By 4 months of age, all animals exhibit focal lesions and nodules consisting primarily of small basophilic cells, many of which exhibit considerable cytoplasmic vacuolization. Mating of animals each bearing the transgene results in rats with a demyelinating condition that develops acutely in pregnant females and more chronically in males. Ultrastructural studies of these cells indicate that the vacuoles contain substantial amounts of glycogen, with the cells resembling hepatoblasts. Malignant neoplasms with both a glandular and a hepatoblastoma/hepatocellular carcinoma pattern arise from the nodules. Enzyme and immunohistochemical studies of all lesions reveal many similarities in gene expression to comparable lesions in rats subjected to chemically induced hepatocarcinogenesis, with certain exceptions. The placental form of glutathione-S-transferase is absent from all lesions in the transgenic animal, as is the expression of connexin 32. A significant number of lesions express serum albumin, and many, but not all, exhibit the T antigen. Lesions expressing the T antigen also contain stainable amounts of the p53 gene product; by contrast, normal hepatocytes express only very low levels of the T antigen within their nuclei and no demonstrable p53. All of the animals develop hepatic lesions, and approximately one-third also develop adenomas and carcinomas derived from the islet cells of the pancreas. Although there are differences in the morphology, biology, and genetic expression in early and late hepatic lesions in this strain of transgenic rat, many similarities also occur, making this a potential model system with which to study the interactions of environmental factors with a genetic program for hepatocarcinogenesis. 相似文献
997.
998.
L B Haas 《Nurse practitioner forum》1991,2(3):166-174
Drug therapy with oral hypoglycemic agents and insulin are components of diabetes management regimens that also include diet, exercise/activity, monitoring, and education. Major concerns for practitioners using drug therapy are selection of the appropriate therapy for a particular patient, and drug interactions and side effects. Drug therapy is based on knowledge of the medications' pharmacokinetics; glucose goals, as determined by practitioners and patients; common sense; and strong participatory relationships between practitioners and patients and, if indicated, families. When using insulin, practitioners need to consider the differences between insulin therapy for insulin-dependent and non-insulin-dependent diabetes; how to initiate, adjust, and supplement insulin; situations that require variations in insulin therapy; and injection mechanics. 相似文献
999.
1000.
F. Girardi H. Pickel J. Haas H. Pfister P. Fuchs 《Archives of gynecology and obstetrics》1989,245(1-4):543-544
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