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151.
This study is focused on Medieval Roman heavy lead-glazed ceramics from the archaeological site of the Caesar's Forum (Rome, Italy), dated from the 10th and not beyond the first decades of the 11th century. Optical microscopy (OM), X-ray powder diffraction (XRPD), scanning electron microscopy (SEM-EDS) and electron microprobe analysis (EMPA) have been used for the archaeometric characterization of the ceramics. Petrographic analysis of the body indicated the occurrence of three petro-fabrics, mainly composed by abundant quartz, feldspars, nodules of iron oxides, rare fragments of siliceous rocks, very rare fragments of calcareous rocks, pyroxene, biotite and olivine. This mineralogical assemblage suggests that the ceramics were fired in the range 950–1050 °C, under oxidizing conditions. SEM and EMP analysis show that the ceramic body was produced with non-or moderately calcareous clays and the heavy glaze with lead oxide, silica, alumina and alkalis. The microstructure of the glaze and the relationship with the body suggest that for the production of the ceramic repertoire of the Caesar's Forum either the single or the double firing techniques were used.  相似文献   
152.
Nine bacterial strains capable of utilising phenol and 2,4‐dichlorophenol (DCP) have been isolated from a mixed culture grown on substrates containing these compounds. One of these strains, a Micrococcus sp, was further investigated under aerobic conditions using phenol and DCP as sole carbon and energy sources at various pH values. Phenol degradation was enhanced under alkaline conditions, and up to 500 mg dm?3 phenol was mineralised within 50 h at pH 10. DCP was more recalcitrant; however up to 883 mg g?1 and 230 mg g?1 were degraded within 10 days, when using initial DCP concentrations of 100 and 200 mg dm?3, respectively. Biomass measurements showed cell growth, proving that both phenol and DCP are used as growth substrates for this isolate. Copyright © 2003 Society of Chemical Industry  相似文献   
153.
Foreword     
This special issue contains selected papers from FUN with Algorithms 2004, the third conference dedicated to the design, analysis, and use of algorithms and data structures that provide amusing, witty, but nonetheless original and scientifically profound contributions to the area.  相似文献   
154.
The authors confirm the fundamental role of the pulse-echo technique in the study of pelvic masses; they outline the usefulness of the ultrasonography in the early presumptive diagnosis of the possible neoplastic alterations of such masses. The authors present five clinical cases in which the use of the pulse-echo technique has allowed to locate, in spite of a scanty clinical symptomatology, the presence of pathologies requiring a rapid surgical resolution.  相似文献   
155.
Maternal pre-pregnancy obesity is a risk factor for pre-eclampsia (proteinuric hypertension in pregnancy) among North American and European women. We studied the relationship between maternal obesity and risk of pre-eclampsia among Zimbabwean women. A case-control study was conducted at Harare Maternity Hospital, Harare, Zimbabwe, between June 1995 and April 1996. Study participants were 144 women with pre-eclampsia and 194 normotensive women serving as controls. Maternal weight, height and mid-arm circumference were measured and recorded during study participants' postpartum hospital admission. Maternal mid-arm circumference, considered to be relatively stable during pregnancy among women of developing countries, was used as the primary indicator of maternal pre-pregnancy obesity. Logistic regression procedures were used to estimate odds ratios and 95% confidence intervals. There were linear trends in risk of pre-eclampsia with increasing mid-arm circumference, increasing weight and increasing body mass index. After adjusting for potential confounding factors, women in the highest quintile for mid-arm circumference (28-39 cm) were 4.4 times more likely to have had their pregnancy complicated by pre-eclampsia than women in the lowest quintile (21-23 cm). Odds ratios of similar magnitude were observed for the other anthropometric measures. To our knowledge, this is the first study to demonstrate a positive association between maternal obesity and pre-eclampsia risk in a black African population. Biological mechanisms thought to explain this relatively consistent epidemiological finding include endothelial cell injury, possibly resulting from hyperlipidaemia.  相似文献   
156.
A clinical laboratory evaluation was conducted on the Clinitek Auto 2000, the Super Aution Analyzer and the Urotron RL9 for the determination of glucose, protein, pH, blood, ketone-bodies and bilirubin.Precision of the systems was tested using three commercial control urine materials, and reported as the percentage of times the instrument repeats a certain value. Good repeatability was obtained with all the instruments.Accuracy of the systems was evaluated by comparison with quantitative procedures, and to check agreement between methods yielding semi-quantitative and quantitative results, ranges of acceptability were defined, based on the criteria reported in a previous paper [2]. It was then found that 87.5 to 98.9% of results from the Urotron RL9 and the Clinitek Auto 2000 were acceptable. With the Super Aution Analyzer the level of agreement was apparently lower because of the higher number of concentration steps used by this instrument.  相似文献   
157.
Measurement of the gradient of the gravitational acceleration from a satellite platform is likely to provide the next improvement in knowledge of the Earth's gravity field after the upcoming Geopotential Research Mission (GRM). Observations from the subsatellite of a Tethered Satellite System (TSS) would increase sensitivity and resolution due to the low altitude possible. However, the TSS is a dynamically "noisy" system and would be perturbed by atmospheric drag fluctuations. The dynamic noise is being modeled in order to evaluate the feasibility of TSS gradiometry and to design methods of abating the error caused by this noise. The demonstration flights of the TSS will provide an opportunity to directly observe the dynamical environment and refine modeling techniques.  相似文献   
158.
159.
INTRODUCTION: Oral NSAIDs cause acute gastric injury that resolves, despite continued administration, by a process known as adaptation. Little is known about the factors that influence this process. METHODS: Sixty-two healthy volunteers were given a 28-day course of either etodolac 300 mg b.d. (13 subjects), naproxen 500 mg b.d. (23), enteric-coated diclofenac (10) or effervescent diclofenac 50 mg b.d. (16). All subjects were gastroscoped before and on days 1, 7 and 28 during drug administration, to assess gastric mucosal damage using a modified Lanza scale. Subjects were then divided into three categories: those who adapted completely, those who adapted incompletely and those who showed no adaptation. The proportion of subjects in each group was compared with respect to age, gender, smoking, the presence of Helicobacter pylori, and the NSAID prescribed. RESULTS: Fifty-nine subjects (median age 25.0 years, range 18-70) developed initial gastric injury to NSAIDs of whom 42 adapted completely, 13 adapted incompletely and four showed no evidence of adaptation. The mean age of subjects was lower in those who adapted (26.8 +/- 9.8 years) than those who adapted incompletely (32.5 +/- 10.3 years) and those who did not adapt (42.0 +/- 15.7 years, P = 0.01). There was no evidence of gender influencing adaptation. Of 17 H. pylori-positive subjects, a higher proportion had incomplete adaptation, with only nine subjects adapting completely (53% vs. 81%, P = 0.04). Sixteen subjects were smokers, of whom a greater proportion showed no evidence of adaptation (19% vs. 2%, P = 0.03). A smaller proportion of those who took naproxen (48%) adapted completely than those who took enteric-coated diclofenac (89%), effervescent diclofenac (75%) or etodolac (91%, P = 0.03). CONCLUSION: Some adaptation occurred in over 90% of subjects after 4 weeks dosing with an NSAID, but adaptation was less frequent in older subjects and in smokers. Complete adaptation occurred less frequently in H. pylori-positive subjects and in those who were given naproxen.  相似文献   
160.
The enzyme Zmp1 is a zinc‐containing peptidase that plays a critical role in the pathogenicity of Mycobacterium tuberculosis. Herein we describe the identification of a small set of Zmp1 inhibitors based on a novel 8‐hydroxyquinoline‐2‐hydroxamate scaffold. Among the synthesized compounds, N‐(benzyloxy)‐8‐hydroxyquinoline‐2‐carboxamide ( 1 c ) was found to be the most potent Zmp1 inhibitor known to date, and its binding mode was analyzed both by kinetics studies and molecular modeling, identifying critical interactions of 1 c with the zinc ion and residues in the active site. The effect of 1 c on intracellular Mycobacterium survival was assayed in J774 murine macrophages infected with M. tuberculosis H37Rv or M. bovis BCG and human monocyte‐derived macrophages infected with M. tuberculosis H37Rv. Cytotoxicity and genotoxicity were also assessed. Overall, inhibitor 1 c displays interesting in vitro antitubercular properties worthy of further investigation.  相似文献   
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