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101.
MT A?ón LM Ruiz-Velasco E Borrajo C Giner M Sendino R Cantón 《Canadian Metallurgical Quarterly》1993,11(10):559-561
BACKGROUND: Escherichia vulneris is an enterobacteriaceae seldom isolated in microbiology laboratories. We report two cases of infection with positive cultures for this microorganism. METHODS: Microbiological cultures of wound secretion and peritoneal fluid on usual media. Identification by PASCO and API 20E systems. Antimicrobial sensitivity was performed by a commercial microdilution system. RESULTS: The first case is a postsurgical hand infection from which was isolated Escherichia vulneris with Enterococcus faecium, it shows the typical presentation of infection by this bacteria. The second case consists of a peritonitis after aggressive abdominal surgery. In the peritoneal fluid culture, Escherichia vulneris and Cedecea neteri were recovered. CONCLUSIONS: The isolation of Escherichia vulneris has not been reported previously in Spain. We contribute towards its better knowledge with two clinical reports: a typical infection and an exceptional isolation from peritoneal fluid. 相似文献
102.
N-phenyl-carbamate of D-mannonohydroxymolactone (I) was synthesized from mannose and was shown to be the best competitive inhibitor of beta-mannosidase so far reported (Ki = 25 nM). 相似文献
103.
A new method based on jackknifing is presented for measuring the difference between two conditions in the onset latencies of the lateralized readiness potential (LRP). The method can be used with both stimulus- and response-locked LRPs, and simulations indicate that it provides accurate estimates of onset latency differences in many common experimental conditions. 相似文献
104.
105.
I Herrero MT Miras-Portugal J Sánchez-Prieto 《Canadian Metallurgical Quarterly》1998,273(4):1951-1958
We have investigated the role of metabotropic glutamate receptors linked to phosphoinositide hydrolysis in the control of glutamate release in cerebrocortical nerve terminals. The activation of these receptors with the agonist 3,5-dihydroxyphenylglycine enhanced intra-synaptosomal diacylglycerol and facilitated both the depolarization-induced increase in the cytosolic free Ca2+ concentration and the release of glutamate. However, 5 min after receptor activation, a second stimulation of the pathway with the agonist failed to produce diacylglycerol and to facilitate glutamate release. Interestingly, during the period in which the diacylglycerol response was desensitized, a strong agonist-induced inhibition of Ca2+ entry and glutamate release was observed. This change in the presynaptic effects of 3,5-dihydroxyphenylglycine is reversible since 30 min after the first stimulation, the agonist-induced inhibition of release disappeared, whereas both the production of diacylglycerol and the facilitation of glutamate release were recovered. The tonic elevation of the extracellular glutamate concentration from basal levels (0.8 microM) up to 5 microM also produced the switch from facilitation to inhibition in the receptor response. The existence of this activity-dependent switch in the presynaptic control of glutamate release suggests that release facilitation is limited to conditions under which an appropriate clearance of synaptic glutamate exists, probably to prevent the neurotoxic accumulation of glutamate in the synapse. 相似文献
106.
Reduction in the moisture content of the medium produced a profound effect on the colony morphology of Campylobacter fetus subsp. jejuni. Fresh medium produced flat, grayfish, spreading colonies with an irregular shape and variety appearance. Plates that were incubated at 30 degrees C for 48 h produced round, convex, butyrous colonies with an entire edge. Plates incubated at 30 degrees C for 24 h before inoculation produced colonies of an intermediate nature; they were round and raised, but not convex, and slightly water or mucoid in nature. This marked effect produced by moisture content of the medium was reproducible and may account for the variation in colonies observed by other investigators. 相似文献
107.
108.
We previously examined Moloney murine leukemia virus-induced fusion-from-within (FFWI) and fusion-from-without (FFWO) of SC-1 mouse cells. FFWI and FFWO can be distinguished by their stimulation by ionophores and polycations, respectively. FFWI is caused by infected cells. Normally, fusion between an infected cell and uninfected cells (heterofusions) is described, but we have surprisingly found that the infected cells also caused homofusion between uninfected cells in their vicinity (named neighbor homofusions). It was shown that neighbor homofusions were not induced by free virus particles (by FFWO). Transfectants expressing envelope proteins only induced heterofusions, indicating that virus production is necessary for the formation of neighbor homofusions. Both plasma membrane fragments and easily removable material from the surface of infected cells were able to induce fusion with the same stimulation pattern as FFWI and neighbor homofusion. These materials, especially the latter, have properties in common with virions, and it is discussed whether immature virions are involved in the formation of the neighbor homofusions. 相似文献
109.
110.
The main result of this paper is a characterization of the space induced by Scott topology on the set of total objects of a bounded-complete cpo. This characterization is simple with bounded-complete algebraic cpo's where a family of clopen sets plays an essential role in the characterization. In the more general case of continuity, one can only produce distinct families of open sets and closed sets to axiomatize the essential properties of a total space. Besides the main characterization, we also discuss its relation to continuous spaces, studied in our earlier paper, and the relation between compact T spaces and total spaces under the lower topology. 相似文献