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991.
Annunziata Faustini Massimo Sangalli Francesco Forastiere Carlo A. Perucci Mirella Fantasia Rosa Manganello Eva Mattaccini Maria T. Topi Rita Trippanera Ugo La Rosa Domenico Spera 《European journal of epidemiology》1998,14(1):99-106
A biphasic outbreak of gastroenteritis caused by Salmonella hadar affected canteen employees and workers at a construction site in central Italy in September 1994. There were 448 symptomatic cases, from 61 of whom group C Salmonella was isolated. Six cases were canteen employees. Twenty-two other individuals were asymptomatic excreters. There were 10 secondary cases. Working as a food handler at the canteen constituted an increased risk of infection, independently of ingestion of the food (odds ratio: 62.1; 95% confidence interval (CI): 9.5– 406.6). Having eaten at the canteen on the 19th and 20th September was identified as risk factor for subjects symptomatic within 72 hours (relative risk (RR): 17.0, 95% CI: 2.3–124.3), and cooled meat salad was identified as the vehicle of infection (RR: 36.6, 95% CI: 14.3–93.8). The use of portable toilets was another possible route of transmission of infection for all cases (RR: 1.3, 95% CI: 1.0–1.6). The index case was a cook who had symptoms five days before the peak of the outbreak. From 27 individuals both symptomatic and asymptomatic excreters group B, group D and not-typed Salmonellas were isolated. This study underlines the problem of improper food handling in salmonellosis outbreaks and emphasizes the role of several vehicles in the transmission of salmonellosis in a community. 相似文献
992.
Jrg F. Debatin John A. Strong H. Dirk Sostman Rosa Negro-Vilar Susan S. Paine James M. Douglas Norbert J. Pelc 《Journal of magnetic resonance imaging : JMRI》1993,3(3):443-450
In the postoperative patient with anginal symptoms, differentiation between bypass graft compromise and nonischemic causes has until now been accomplished only by means of x-ray angiography. A noninvasive test is clearly desirable. The authors used a cine phase-contrast (PC) magnetic resonance (MR) imaging technique to characterize blood flow in native and grafted internal mammary arteries (IMAs). Ten volunteers and 15 patients who had recently undergone IMA coronary artery bypass grafting were imaged. Cine PC MR imaging was performed in the transaxial plane at the level of the pulmonary artery bifurcation. Flow in both IMAs was quantified and expressed as a percentage of cardiac output measured in the ascending aorta. In the 15 patients, flow analysis was performed in both the native and grafted IMAs. In the volunteers, IMA blood flow ranged from 2.1% to 4.3% of cardiac output on the left (mean, 3.5%) and 2.1% to 5.1% (mean, 3.5%) on the right. There was considerable intersubject variability, with coefficients of variation of 10.7% for the left and 12.3% for the right IMA. Intrasubject variability was limited, with estimated common standard deviations of 0.45% of cardiac output (range, 0.2%–1.1%) for the left and 0.39% (range, 0.1%–0.6%) for the right IMA. Flow in grafted IMAs was identified in 13 of 15 patients. In one of two patients without demonstrable IMA graft flow, cardiac catheterization confirmed lack of flow. IMA graft flow varied from 28 to 164 mL/min (mean, 80.3 mL/min). This study shows the feasibility of using cine PC MR imaging as a quantitative method of evaluating blood flow in IMA coronary artery bypass grafts. 相似文献
993.
994.
Restoration of active transport of solutes and oxidative phosphorylation by naphthoquinones in irradiated membrane vesicles from Mycobacterium phlei 下载免费PDF全文
Soon-Ho Lee Thomas O. Sutherland Rosa Deves Arnold F. Brodie 《Proceedings of the National Academy of Sciences of the United States of America》1980,77(1):102-106
Irradiation of the inverted membrane vesicles of Mycobacterium phlei with light at 360 nm inactivated the natural menaquinone [MK9(II-H)] and resulted in a loss of substrate oxidation, pH gradient, membrane potential, active transport of proline or calcium ions, and oxidative phosphorylation. Restoration of the protonmotive force and active transport occurred on addition of naphthoquinones such as vitamin K1, menadione, or lapachol to the irradiated membrane vesicles. However, coupled phosphorylation was restored only by vitamin K1. Menadione and lapachol did not act as uncoupling agents. The magnitude of the pH gradient and membrane potential in the quinone-restored system was a reflection of the rate of oxidation and was correlated with the rate of uptake of proline or Ca2+. These results are consistent with the chemosmotic hypothesis proposed for the energy transducing mechanism for active transport and further demonstrate that the complete respiratory chain is not required to drive active transport. In contrast, the data suggest that in addition to the driving force (protonmotive force) necessary to establish oxidative phosphorylation, a specific spatial orientation of the respiratory components, such as the naphthaquinones, is essential for the utilization of the proton gradient or membrane potential or both. Bypass of electrons from the respiratory chain with menadione may explain the inability of this quinone to restore oxidative phosphorylation; however, lapachol restores oxidation by the same electron transport pathway as the natural menaquinone but fails to restore phosphorylation. Because all three quinones restore the protonmotive force, other factors that are discussed must be considered in understanding the mechanism of oxidative phosphorylation. 相似文献
995.
M. Rosa 《Neuroradiology》1976,10(5):243-249
Summary Simultaneous tomography applied to normal vertebral angiography has, by the dissociation of the vascular planes, made a selective and spatial study of the vertebrobasilar circulation possible, and therefore the identification of the vessels which are partly or totally hidden by other vascular structures. This technique has also led to a better delimitation and sometimes a direct observation and spatial localization of some anatomical structures above and below the tentorium.
Angiotomographisches Studium des normalen zerebralen Kreislaufs. Vertebrobasilares System
Zusammenfassung Die simultane an der Vertebralangiographie angewandte Tomographie hat durch die Dissoziation der Gefäßebenen eine selektive und räumliche Untersuchung der Gefäße des vertebrobasilaren Kreislaufs und folglich der Gefäße ermöglicht, die zum Teil oder vollständig durch andere vaskularen Strukturen versteckt werden.Diese Methode hat auch eine bessere Abgrenzung und manchmal eine direkte Beobachtung, sowie eine räumliche Bestimmung einiger anatomischer Strukturen über und unter dem Tentorium erlaubt.
Etude angiotomographique de la circulation cérébrale normale. Système vertébro-basilaire
Résumé La tomographic simultanée, appliquée à l'angiographie vertébrale, a permis, par la dissociation des plans vasculaires, une étude sélective et spatiale des vaisseaux de la circulation vertébrobasilaire et donc l'identification des vaisseaux qui sont partiellement ou totalement cachés par d'autres structures vasculaires. Cette technique a permis aussi une meilleure délimitation et parfois une observation directe et une localisation spatiale de certaines structures anatomiques au-dessus et au-dessous de la tente.相似文献
996.
International aspects of perinatal mortality 总被引:1,自引:0,他引:1
F W Rosa 《Clinical obstetrics and gynecology》1970,13(1):57-78
997.
J R Natiella M A Meenaghan R A Rosa R W Bessette A W Gage 《Journal of oral pathology》1979,8(4):237-246
The minor salivary glands in the hard palate and the submandibular gland of the Rhesus monkey were subjected to a liquid nitrogen, direct-spray, one-cycle freeze. A 4-min freeze in the temperature range of -40 degrees C to -60 degrees C was used. The extent of tissue destruction was determined at intervals up to 1 year. Clinically relevant findings resulted and form the basis for subsequent studies by this group of investigators. 相似文献
998.
Fedele M Pentimalli F Baldassarre G Battista S Klein-Szanto AJ Kenyon L Visone R De Martino I Ciarmiello A Arra C Viglietto G Croce CM Fusco A 《Oncogene》2005,24(21):3427-3435
Overexpression of HMGA1 proteins is a constant feature of human carcinomas. Moreover, rearrangements of this gene have been detected in several human benign tumors of mesenchymal origin. To define the role of these proteins in cell transformation in vivo, we have generated transgenic mice overexpressing ubiquitously the HMGA1 gene. These mice developed mixed growth hormone/prolactin cell pituitary adenomas and natural killer (NK)-T/NK cell lymphomas. The HMGA1-induced expression of IL-2 and IL-15 proteins and their receptors may account for the onset of these lymphomas. At odds with mice overexpressing a wild-type or a truncated HMGA2 protein, adrenal medullar hyperplasia and pancreatic islet cell hyperplasia frequently occurred and no increase in body size and weight was observed in HMGA1 mice. Taken together, these data indicate an oncogenic role of the HMGA1 gene also in vivo. 相似文献
999.
Recent research has highlighted the fundamental role of the tumour's extracellular metabolic microenvironment in malignant invasion. This microenvironment is acidified primarily by the tumour-cell Na(+)/H(+) exchanger NHE1 and the H(+)/lactate cotransporter, which are activated in cancer cells. NHE1 also regulates formation of invadopodia - cell structures that mediate tumour cell migration and invasion. How do these alterations of the metabolic microenvironment and cell invasiveness contribute to tumour formation and progression? 相似文献
1000.
Postprandial hyperglycemia and hyperlipidemia-generated glycoxidative stress: its contribution to the pathogenesis of diabetes complications 总被引:1,自引:0,他引:1
Rebolledo OR Actis Dato SM 《European review for medical and pharmacological sciences》2005,9(4):191-208
Postprandial glucose and triglyceride increments after a mixed meal are more prolonged in people with type 1 and 2 diabetes or with impaired glucose tolerance than in normal individuals. Evidence in the literature suggests that these transient increases represent an additional and independent risk for chronic hyperglycemia to induce endothelial dysfunction, an important fact for the development of diabetic vascular complications. This article presents the more relevant mechanisms by which acute postprandial hyperglycemia and hyperlipidemia have been proved to determine the risk of reactive oxygen species overproduction, an increased synthesis of non enzymatic early-glycated and nitrated proteins, and a more atherogenic lipoprotein profile. Recent recommendations suggest that care for this transient glycoxidative stress should be associated with fasting glucose or HbA1c care, to reduce the risk of macro- and microvascular complications in people with diabetes. 相似文献