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101.
Proverbio AM  Leoni G  Zani A 《Neuropsychologia》2004,42(12):1636-1656
Recent event-related potential (ERP) and neuroimaging studies suggest that bilingual individuals are able to inhibit the processing of a non-target language while speaking or reading in another language. The neural mechanisms subserving code switching still remain matter of debate. The aim of the present study was to shed some light on the neurofunctional bases of such mechanisms. ERPs were recorded in native Italian simultaneous interpreters and monolingual controls during a semantic processing task in which the subjects had to evaluate the sensibleness of final words of incomplete sentences. All participants were strictly right-handed. Interpreters knew at least four languages (from four to eight) at a professional level, from among 11 European and Asian languages, and had an excellent command of English (L2). Four hundred short sentences were presented visually; half of them had an unexpected final word, producing a semantic incongruence. Sentences could be entirely in Italian or in English (unmixed); alternatively, the body of the sentence could be in English and the final word in Italian or vice versa (mixed). ERPs were time locked to the onset of the final word. Both reaction times (RTs) and electrophysiological data indicated a lesser degree of hemispheric lateralization for linguistic function during L2 rather than L1 processing in interpreters. The first effect of lexical switching and code switching was recorded in the time window between 140 and 200 ms at left anterior sites. At N400 level, ERPs were significantly larger to L2 than to L1 words only in the mixed and not in the unmixed condition. No effect of language was observed in the unmixed condition, thus suggesting that the difference in L1/L2 processing was not related to a difference in proficiency, but rather to a different functional organization of semantic integration systems due to the later age of acquisition of L2 compared to L1. Interpreters were faster at reading and comprehending sentences in English ending with an Italian word than vice versa (L2 --> L1 switch).  相似文献   
102.
BACKGROUND: The aim of the present study was to evaluate the role of non-invasive methods in the early detection of pulmonary and cardiac involvement in Systemic sclerosis (SSc) and to identify clinical and/or instrumental patterns of prognostic value. PATIENTS AND METHODS: Twenty female patients affected by SSc (8 with diffuse cutaneous SSc and 12 with limited cutaneous SSc) were enrolled in our study. Cardiac and pulmonary involvement (respiratory function tests and carbon monoxide lung diffusion [DLCO], chest radiography, high resolution computed tomography [HRCT] and lung perfusion magnetic resonance) were evaluated. RESULTS: All 18 patients studied with respiratory function tests showed a significant reduction of DLCO. HRCT was considerably more sensitive than traditional chest radiography (59% versus 28%; p<0.05). Lung perfusion MRI revealed normal findings in 15 patients. Abnormal lung perfusion MRI results were found only in 3 patients. Angina pectoris with electrocardiographic and scintigraphic ischemic changes, severe regional wall motion abnormalities and complex arrhythmias seemed to be associated with poor prognosis. CONCLUSION: Taken together these results indicate that a pulmonary involvement occurs both in limited and in diffuse cutaneous SSc patients and develops, in 83% of the cases, without any regional lung perfusion abnormality. Furthermore, cardiac involvement is detected in 65% of the cases as a consequence of a range of noxious events including myocardial ischemia, fibrosis and pressure overload which may result in ventricular dysfunction and arrhythmias. Lung perfusion MRI should be considered as a complementary diagnostic method for the functional evaluation of these symptoms in systemic sclerosis.  相似文献   
103.
It has been previously demonstrated that some antimicrobial agents enhance activities of human polymorphonuclear neutrophils (PMNs). The effect on the release of cytokines in an inflammatory context from PMNs by these antibiotics was evaluated. We studied the effect of the release of some cytokines by human PMNs RT-PCR analysis on a clinical strain of Klebsiella pneumoniae by comparing the effect with that observed in the presence of co-amoxiclav, sanfetrinem, clarithromycin, prulifloxacin and tobramycin. All the drugs tested were capable of modulating PMN synthesis in vitro of pro-inflammatory cytokines IL-8, IL-1beta, TNF-alpha and IL-6, but not that of anti-inflammatory cytokine IL-10. The degree of their stimulatory or inhibitory potency varied with the cytokine examined.  相似文献   
104.
Pursuing our chemical and biological studies in this field, we described the multistep preparation of the new 5-, 6-, or 7-alkoxy and 7-alkoxy-8-methyl substituted 4-(1-piperazinyl)coumarins 5d-v, as well as the in vitro evaluation of their inhibitory activity on human platelet aggregation induced in platelet-rich plasma by ADP, collagen or the Ca(2+) ionophore A23187. Compounds 5h-j,p,r-u showed notably high activity towards all the platelet aggregation inducers used, and the most active one, 8-methyl-4-(1-piperazinyl)-7-(3-pyridylmethoxy)coumarin (5t), proved to be a potent in vitro antiplatelet agent.  相似文献   
105.
BACKGROUND: Epoetin alfa, administered at standard dosages of 10,000-20,000 IU three times weekly or 40,000-60,000 IU once weekly, has been shown to significantly increase hemoglobin (Hb) levels, decrease transfusion requirements, and improve quality-of-life parameters in patients undergoing chemotherapy.Objective. This open-label, nonrandomized, historically controlled study was conducted to evaluate the efficacy and safety of an induction dose of epoetin alfa in patients with moderate or severe anemia who were receiving chemotherapy. METHODS: Nineteen patients with solid tumors and Hb levels < 9.0 g/dl were enrolled. The patients received single s.c. injections of epoetin alfa, 40,000 IU, on study days 1, 4, 7, 10, and 13, and were then observed for the following 30 days. Nineteen other cancer patients who had matching characteristics and had received epoetin alfa, 10,000 IU, three times weekly for the 45-day study period, served as historical controls. The primary efficacy variable was change in Hb level from baseline to days 15 (approximately week 2) and 45 (approximately week 6.5). Secondary efficacy variables included the percent response (Hb increase > or = 1 g/dl) and percent major response (Hb increase > or = 2 g/dl) at days 15 and 45, the durations of response and major response after day 45, the proportion of patients transfused within the 45 study days, the changes in Eastern Cooperative Oncology Group performance status score at days 15 and 45, and the ability to maintain the planned chemotherapy dose (dose intensity) over the 45-day study. RESULTS: Mean increases in Hb level in the epoetin alfa 40,000 IU group were significantly greater than those in the historical control group both at day 15 and at day 45. The increase in Hb level in the control group approximated increases reported with standard 3-times-weekly epoetin alfa at day 15 but was somewhat lower than the increases typically seen by day 45, presumably due to the fact that, in the present study, the epoetin alfa dose was not doubled in initial nonresponders, as is commonly done with standard epoetin alfa treatment. The rates of major response for epoetin alfa 40,000 IU patients (37% at day 15 and 84% at day 45) were higher than those for control patients (16% and 21%, respectively). Also, the transfusion rate was lower and performance status scores were better in the epoetin alfa 40,000 IU patients than in the control patients. In all, 74% of epoetin alfa 40,000 IU patients versus 47% of control patients received 100% of the planned chemotherapy dose. Epoetin alfa was well tolerated in both treatment groups. CONCLUSIONS: Results of this study suggest that epoetin alfa at a dose of 40,000 IU administered five times over 2 weeks may confer even higher response rates than those seen with standard dosing regimens. These encouraging results support further study of the proposed induction dose of epoetin alfa in a larger, randomized, prospectively controlled trial.  相似文献   
106.
107.
The hospitalisation represents a stressful event, particularly for subjects facing surgical procedures. Assuming this situation is traumatic event in which anxiety and stress are lived experiences, we have analysed their influences and implications of the psychological aspects on surgical nursing care process. Patient affected of a various disease, waiting for surgery have been submitted a two different questionnaire (Cognitive, S.T.A.I.). The finding showed that different specific and complex aspects of hospital life are stressful conditions. The surgical procedures in general cause an increase of the level of anxiety in all subjects examinaed. This phenomenon was greater in those subjects in which the anxious personality was already present and in those with more serious disease. The surgical procedures is a stressful condition that require a positive adaptation for the patient and his relatives. The therapeutical-educative relationships represent the instrument to interact positively with the person and his need to be cured.  相似文献   
108.
Patients undergoing long-term hemodialysis (HD) exhibit increased levels of oxidative stress, likely contributing to the increased rate of cardiovascular disease. The present study represents a critical evaluation of some of the most widely used oxidative indicators, as applied to the monitoring of hemodialysis-associated oxidative stress. Total plasma antioxidant capacity was determined by two independent procedures, the total antioxidant status (TAS) and the ferric reducing ability of plasma (FRAP) methods. Plasma lipid peroxidation was assessed by determining the peroxidation products malonaldehyde and 4-hydroxynonenal (MDA-4HNE) as well as lipid hydroperoxides ("Fox-2" and "d-ROMs" methods). Total plasma thiols and plasma alpha-tocopherol were also determined. MDA-4HNE levels were higher in HD patients and decreased following HD, possibly due to passive diffusion across dialysis filters. d-ROMs were also higher in HD patients but exhibited a further increase following the dialysis procedure. Serum alpha-tocopherol did not show any significant differences. Plasma thiols were lower in HD patients and were restored following HD. Plasma total antioxidant capacity determined with either method was unexpectedly higher in HD patients compared to controls, and decreased following HD. These data indicate that, of the biomarkers studied, d-ROMs level is the one more accurately reflecting the oxidative alterations taking place in HD patients, while determination of MDA-4HNE fails to detect oxidation occurring during the HD sessions. In addition, our findings point out that the determination of total antioxidant capacity in HD patients is severely affected by the concomitant fluctuations in plasma urate levels and therefore needs careful interpretation.  相似文献   
109.
Two cases of acute myeloid leukaemia (AML) with CD2 and CD7 expression associated with diabetes insipidus (DI) as the initial symptom are presented. Both patients had t(3;3)(q21;q26) associated with monosomy 7 and EVI-1 overexpression. No neurohypophysis infiltration was evident. One patient died during induction chemotherapy, the other did not respond to therapy and died with persistent DI. Our findings further support the existence of a distinct AML entity characterized by the presence of DI, abnormalities of chromosome 3q, dysmegakaryopoiesis and poor outcome, and provide evidence of EVI-1 gene involvement. The possible role of chromosome 3q26 abnormalities in determining this peculiar clinical-biological association is emphasized.  相似文献   
110.
Many factors have been proposed as predictors of poor renal prognosis in children with hemolytic uremic syndrome (HUS), but their role is still controversial. Our aim was to detect the most reliable early predictors of poor renal prognosis to promptly identify children at major risk of bad outcome who could eventually benefit from early specific treatments, such as plasmapheresis. Prognostic factors identifiable at onset of HUS were evaluated by survival analysis and a proportional hazard model. These included age at onset, prodromal diarrhea (D), leukocyte count, central nervous system (CNS) involvement, and evidence of Shiga toxin-producing Escherichia coli (STEC) infection. Three hundred and eighty-seven HUS cases were reported; 276 were investigated for STEC infection and 189 (68%) proved positive. Age at onset, leukocyte count, and CNS involvement were not associated with the time to recovery. Absence of prodromal D and lack of evidence of STEC infection were independently associated with a poor renal prognosis; only 34% of patients DSTECrecovered normal renal function compared with 65%–76% of D+STEC+, D+STEC and DSTEC+ patients. In conclusion, absence of both D and evidence of STEC infection are needed to identify patients with HUS and worst prognosis, while D but STEC+ patients have a significantly better prognosis.  相似文献   
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