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1.
Some cephalosporanic acid derivatives substituted on the C(7) amino nitrogen with (arylmethyloxyimino)acetyl moieties were synthesized and tested in vitro for their antimicrobial activity against Gram positive and Gram negative bacteria. The new compounds showed a modest activity directed only against Gram positive microorganisms.  相似文献   
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In this paper we report the results of a nosocomial infections surveillance system "Laboratory Based". The system started in August 1995 at San Giovanni Hospital, Rome. All the specimens sent to the Microbiology Laboratory have been registered using a computerized input form. 12,204 forms, attributable to patients between 0 and 97 years (median 43 years) resulted evaluable. The global rate of incidence of nosocomial infection was, in the study period, 16 per one thousand person/day. The rate of incidence, when stratified for the medical, surgical and emergency boards, was, respectively, 19 per one thousand person/day in the medical facilities, 15 per one thousand person/day in surgical and 17 per one thousand person/year in emergency facilities. The nosocomial infections incidence correlated well with the age of the patients and the time of bed stay. The bulk of infections were localized to the respiratory apparatus. Localization to urinary apparatus and sepsis follow. The isolated microbes were (38%) gram-negative microbes; the 38% of the isolates are gram-negative microbes and the 24% are Mycetes. Our data validate the surveillance system in a great hospital of Rome metropolitan area.  相似文献   
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Bulletin of Engineering Geology and the Environment - The deterioration of a stone material is related to its pore structure, which affects the interaction between surface and environmental agents....  相似文献   
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Herein, we report the synthesis of novel stable analogues of geranylgeranyl diphosphate (GGPP), in which the "natural" all-trans geranylgeranyl portion has been replaced by a (Z,E,E)-geranylgeranyl chain. The change in configuration and consequent change in the relative position of the polar portion with the lipophilic side chain did not improve the properties of the E,E,E analogues in their inhibition of geranylgeranyl protein transferase I (GGTase I). However, a significant level of GGTase I inhibition and selectivity for GGTase I over farnesyl transferase (FTase) was maintained the unsubstituted phosphonoacetamidoxy derivative 4 a. This has shed light on the relative importance of the configuration at the C2=C3 double bond among GGPP derivatives. Moreover, the biological activities of all the compounds reported herein, in particular the preferential FTase inhibitory activity shown by compound 6, were in good agreement with the results of docking analysis.  相似文献   
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3-Phenylpiperidines (PPEs) have been thoroughly investigated in view of their interesting dopaminergic activity, and the N-n-propyl substitution has been suggested as the most effective among several PPEs differently substituted on the phenyl ring. In previous studies, we found that the dimethyl substitution on the phenyl ring of N-unsubstituted PPEs provided compounds active toward alpha2-adrenergic receptors (alpha2-ARs), which proved to possess interesting selectivity properties. The high degree of homology between the binding domains of alpha2-ARs and D4-dopaminergic receptors (D4-DARs) prompted us to verify whether this kind of substitution on the aromatic ring might prove to be active against retinal DARs of the D4 subtype. On the basis of these premises, we synthesized the dimethylphenyl-substituted PPEs 4a-f, in which an n-propyl chain is present on the aminic nitrogen. Radioligand binding assays on bovine retina and striatum membranes for D1-like and D2-like DARs indicated that PPEs 4a, 4b, and 4f possess a high affinity and selectivity for the D4-DAR subtype of bovine retina.  相似文献   
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The main aim of this work was to evaluate the leaching of copper in grappa from distillation plant that treats Cabernet and Sangiovese marcs (Montepulciano and Chianti, Tuscany). Copper content (determined by atomic absorption spectrometry, AAS) was 1.05 ± 0.03 mg L?1 in industrial distillates (Cabernet marc, 82.3% alcohol, v/v), and 3.7 ± 0.2 μg L?1 in artificial grappa (62.0%, Cabernet) obtained by distilling marc in a laboratory‐scale glassware plant. The artificial grappa distillate was refluxed over copper shavings, and copper content, CCu, was analysed in relation to reflux time and wear of the copper bell. The results showed that CCu trend was almost linear with increasing alcohol concentration and constant reflux time, and vice versa. The ratios of selected volatile components were not influenced by reflux on the shavings.  相似文献   
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We have made deletions in a human interleukin 1 beta cDNA clonedin a yeast vector capable of directing the expression and secretionof foreign protein. Deletions at either the 5' or 3' end ofthe cDNA result in a dramatic drop in yield of protein. An investigationof some possible causes points to in stability of the truncatedpeptides as a major factor contributing to low yield. The resultssuggest that correct folding of mature interleukln 1 into aprotease resistant form requires almost the entire polypeptide.  相似文献   
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