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41.
Marco Lembo Carmela Vedetta Umberto Moscato Michele del Gaudio 《La Medicina del lavoro》2021,112(2):123
Introduction:Due to the COVID-19 pandemic, healthcare workers are now required to use additional personal protective equipment (PPEs) to protect themselves against the virus. That led to an increased clothing insulation which is negatively affecting the perceived healthcare workers’ thermal sensation.Objectives:While demonstrating through software simulations the potential level of thermal discomfort healthcare workers involved in the COVID-19 emergency can be subjected to, this work aims at identifying measures to improve thermal sensation perception and acceptable thermal conditions for medical personnel.Methods:After having obtained the insulation values of individual clothing used by staff during COVID-19 emergency through the use of a thermal well-being evaluation software, the Fanger indexes (PMV - Predicted Mean Vote and PPD - Predicted Percentage of Dissatisfied) were calculated in order to estimate staff satisfaction to microclimatic conditions.Results:The use of COVID-19 additional PPEs with an air temperature equal to 22 °C (normally considered optimal) brings the PMV index equal to 0.6, which corresponds to 11.8 % being unsatisfied (PPD) due to perceived heat.Discussion:The use of additional protective devices significantly increases the clothing insulation level, facilitating the onset of conditions of thermal discomfort in the health workers. Workers engaged in the execution of nasopharyngeal swabs were most affected by the summer weather conditions and certainly represent the most critical category, for which it would be recommended to implement a higher turnover of service to reduce individual exposure time and consequent discomfort. 相似文献
42.
Luisa Zanette Massimo Zucchetti Andrea Freshi Domenico Erranti Umberto Tirelli Maurizio D'Incalci 《Cancer chemotherapy and pharmacology》1990,25(6):445-448
Summary The clinical pharmacokinetics of 4-demethoxydaunorubicin was investigated in 28 cancer patients who received the drug orally. The majority of the patients were elderly (median age, 72 years). Nine of them also received an i. v. dose, and the bioavailability of the oral dose ranged between 9% and 39%. 4-Demethoxydaunorubicin peak levels were achieved 2–4 h after the oral dose in most patients. The drug was rapidly and extensively metabolized to 4-demethoxy-13-hydroxydaunorubicin, which is probably as active as the parent drug. The metabolite levels were much higher and longer lasting than the parent drug, suggesting that it may play an important role in the drug's pharmacological effects. 相似文献
43.
Maria Rosaria Melis Salvatora Succu Umberto Iannucci A. Argiolas 《Naunyn-Schmiedeberg's archives of pharmacology》1997,355(5):595-600
The possible involvement of nitric oxide in the prevention by morphine of apomorphine- and oxytocin-induced penile erection
and yawning was investigated by measuring the concentration of NO2- and NO3- in the dialysate obtained with a vertical microdialysis probe implanted in the paraventricular nucleus of the hypothalamus
of male rats. Either apomorphine (80 μg/kgs.c.) or oxytocin (30 ng i.c.v.) increased significantly basal NO2- and NO3- concentration in the paraventricular dialysate, penile erection and yawning. Morphine (1, 5 and 10mg/kg i.p.) prevented
dose-dependently either apomorphine or oxytocin responses when given 15min before apomorphine or oxytocin. Prevention by morphine
of apomorphine and oxytocin responses was abolished by naloxone (3mg/kg i.p.) given 15min before morphine. Morphine prevented
apomorphine and oxytocin responses also when given in the lateral ventricles or directly in the paraventricular nucleus. In
contrast, the selective agonist of the kappa opioid receptor subtype U-69,593 was found to be ineffective. The present results
confirm previous findings showing that morphine acts through μ receptors in the paraventricular nucleus to prevent apomorphine
and oxytocin-induced penile erection and yawning and suggest that this morphine effect is mediated by a decreased activity
of nitric oxide in the paraventricular nucleus of the hypothalamus.
Received: 30 September 1996 / Accepted: 24 January 1997 相似文献
44.
Cardillo C Mores N Campia U Musumeci V Motolese M Folli G 《American journal of therapeutics》1994,1(3):198-205
The current study analyzed the effects of different doses of the calcium channel blocker felodipine on cardiovascular response to a set of standardized laboratory tasks. We randomly allocated 21 essential hypertensive patients to receive extended release felodipine 5 mg, felodipine 10 mg and placebo, each given once daily for 2 weeks, according to a double-blind 3-period design. At the end of each treatment period, patients were examined at resting baseline and while performing a mental arithmetic test, a handgrip test and a cycle ergometry test. Compared to placebo, the average fall in resting blood pressure (BP) was of 7.9 ± 5.6/6.1 ± 4.5 mm Hg with felodipine 5 mg (p < 0.01) and of 15.1 ± 5.8/13.9 ± 4.5 mm Hg with felodipine 10 mg (p < 0.001). During mental arithmetic, BP decrease was 11.6 ± 8.1/9 ± 5 mm Hg with felodipine 5 mg (p < 0.01) and 20.4 ± 8.1/15.3 ± 5 mm Hg with felodipine 10 mg (p < 0.001). During handgrip test, BP was significantly reduced after both felodipine doses by 11.7 ± 9.3/9.5 ± 6.5 mm Hg (p < 0.05) and 22.1 ± 9.3/22.4 ± 6.5 mm Hg (p < 0.001), respectively. During cycle ergometry, systolic BP was significantly reduced after felodipine 10 mg by 20.1 ± 9.4 mm Hg (p < 0.001), whereas the fall induced by felodipine 5 mg (7.7 ± 9.4 mm Hg) was not statistically significant (p > 0.05); diastolic BP was significantly reduced by both felodipine doses [average fall of 6.6 ± 5.8 mm Hg (p < 0.05) after felodipine 5 mg and of 12.7 ± 5.8 mm Hg (p < 0.001) after felodipine 10 mg]. There was no treatment effect on the magnitude of systolic BP reactivity from baseline during either mental arithmetic, handgrip test or cycle ergometry (all, p > 0.05). Heart rate values were significantly higher after both felodipine doses than after placebo, either at rest or during stress testing (all, p < 0.05). These data suggest that felodipine, especially at higher doses, may be effective in lowering BP not only at rest but also during exposure to commonly recurring stressful situations. 相似文献
45.
A. Mazza E. Casiglia R. Scarpa V. Tikhonoff A. Pizziol E. Sica A.C. Pessina 《European journal of epidemiology》1999,15(5):421-427
Cancer mortality was analysed in 3282 elderly subjects aged 65 years from 2 cohorts of general population having different life-style patterns. They took part in the CASTEL (CArdiovascular STudy in the ELderly), a 12-year lasting prospective Italian study. The aim of the present analysis was to identify the items able to influence cancer mortality. A biochemical profile and a questionnaire on lifestyle were collected. Continuous items were averaged and compared with analysis of variance, frequencies with the Pearson's 2 test. Mortality was recorded yearly for 12 years from the Registrar's Office and causes of death double-checked by consulting medical case sheets and family doctors' files. The influence of items on mortality was evaluated with the Cox multivariate analysis. Relative risk (RR) of each item was adjusted for confounders. Age, gender, tobacco smoking, the presence of respiratory symptoms, low body mass index in males, serum alanine transaminase (ALT) and alkaline phosphatase (ALP), as well as the town of residence, were powerful predictors of cancer mortality. In the entire population, 12-year overall mortality was 49.4%, cardiovascular 22.8%, and neoplastic 11%; the latter was higher in males than in females (15.7% vs. 7.9%, p < 0.00001). In subjects with respiratory symptoms neoplastic mortality was 11.6% (RR: 1.47) vs. 9.7% in those without symptoms (p < 0.01). Subjects with very low cholesterol ( 178 mg/dl), those with high uric acid ( 8.7 mg/dl) and males with low body mass index ( 22.7 kg/m2) has an increased risk of cancer mortality. RR of cancer mortality increased with increasing ALT or ALP. It was 1 in those having ALT and ALP between 9 and 41.2U/I, 1.41 in those exceeding this latter level and < 1 in those below 9U/I. RR of ALP had a similar trend, the best protective cut-off value being <106 and the worst one > 177U/I. When both serum enzymes were simultaneously raised, RR of cancer mortality increased to 2.84. 相似文献
46.
G G Haddad M A Epstein R A Epstein N M Mazza R B Mellins E Krongrad 《Pediatric research》1979,13(2):136-138
The QT interval was measured in 12 normal and 7 aborted sudden infant death syndrome (SIDS) infants in rapid eye movement (REM) and quiet sleep at monthly intervals through the age of 4 months. An accuracy of better than 2 msec was assured by high resolution of the digitized signal and calibration of each QT measurement with an accurately generated time code. In contrast to current speculations, the QT index was significantly smaller in the infants with aborted SIDS than in the normal infants in both REM and quiet sleep (P less than 0.05). In addition, as in normal infants, the QTc was smaller in REM than in quiet sleep (P less than 0.01). Although these results offer no support for the hypothesis that SIDS results from prolongation of the QT interval, they suggest that aborted SIDS infants have a functional abnormality in the autonomic nervous system. 相似文献
47.
The locomotor activity of C57B1/6J and DBA/2J mice was studied, under the influences of heroin, amphetamine, strychnine, or ethanol, and of combinations of the opiate with each one of the other drugs. Heroin treatment was followed by the typical running fit in the C57 mice, while the DBA strain was unaffected. Amphetamine enhanced the activity in the C57 strain only. The combination of heroin with amphetamine or ethanol increased the locomotor activity only in the DBA strain, while heroin + strychnine exerted a clear stimulating effect on the activity of the C57 mice. The strychnine + heroin mixture was more toxic than heroin alone when the lethal doses (LD50) were determined in the 2 strains. 相似文献
48.
Guglielmo Nasti Renato Talamini Andrea Antinori Ferdinando Martellotta Gaia Jacchetti Francesco Chiodo Giuseppe Ballardini Laura Stoppini Giovanni Di Perri Maurizio Mena Marcello Tavio Emanuela Vaccher Antonella D'Arminio Monforte Umberto Tirelli 《Journal of clinical oncology》2003,21(15):2876-2882
PURPOSE: To assess potential new prognostic factors and to validate the AIDS Clinical Trials Group (ACTG) for AIDS-related Kaposi's sarcoma (AIDS-KS) staging system in the highly active antiretroviral therapy (HAART) era. PATIENTS AND METHODS: We collected epidemiologic, clinical, staging, and survival data from 211 patients with AIDS-KS enrolled in two prospective Italian human immunodeficiency virus (HIV) cohort studies. We included in the analysis all patients with the diagnosis of KS made from January 1996, the time at which HAART became available in Italy. RESULTS: In the univariate analysis, survival was not influenced by sex, age, level of HIV viremia at KS diagnosis, HAART at KS diagnosis (HAART-na?ve v HAART-experienced), or type of HAART combination. Regarding ACTG classification, the 3-year survival rate was 85% for T0 patients and 69% for T1 patients (P =.007), 83% for S0 patients and 63% for S1 patients (P =.003), and 83% for I0 patients and 71% for I1 patients (P =.06). In the multivariate analysis, only the combination of poor tumor stage (T1) and poor systemic disease (S1) risk identified patients with unfavorable prognosis. The 3-year survival rate of patients with T1S1 was 53%, which was significantly lower compared with the 3-year survival rates of patients with T0S0, T1S0, and T0S1, which were 88%, 80%, and 81%, respectively (P =.0001). CONCLUSION: In the era of HAART, a refinement of the original ACTG staging system is needed. CD4 level does not seem to provide prognostic information. Two different risk categories are identified: a good risk (T0S0, T1S0, T0S1) and a poor risk (T1S1). 相似文献
49.
Franca Formelli Tiziana Camerini Elena Cavadini Valentina Appierto Maria Grazia Villani Alberto Costa Giuseppe De Palo Maria Gaetana Di Mauro Umberto Veronesi 《Cancer epidemiology, biomarkers & prevention》2003,12(1):34-41
OBJECTIVES: To assess, in women participating in a breast cancer prevention trialon fenretinide (4-HPR), the relationship of drug and retinol levels with the risk of second breast malignancy, taking into account age and menopausal status. METHODS: In a multicenter prevention trial, women with early breast cancer were randomly assigned to receive no treatment or 200 mg of 4-HPR/day for 5 years. Blood was collected at baseline and on a yearly basis during intervention from women recruited at the Istituto Tumori (Milan, Italy; 818 and 756 in the 4-HPR and control arm, respectively, who accounted for 53% of the participants in the trial). The plasma concentrations of 4-HPR, its main metabolite N-(4-methoxyphenyl) retinamide, and retinol were assayed by high-performance liquid chromatography. Three age ranges (or=56 years), menopausal status at baseline, and disease outcome at a median follow-up of 97 months were taken into account in the analysis. RESULTS: Baseline retinol levels were significantly lower (P or=46 years versus or= 0.71; P 相似文献
50.
Santarossa Sandra Vaccher Emanuela Balestreri Luca Volpe Rachele Tirelli Umberto 《Journal of neuro-oncology》1997,35(2):141-143
Patients with locally advanced transitional cell carcinoma (TCC)of the bladder are at high risk forsystemic relapse, with liver, bone and lung beingthe commonest sites of metastases.We report the case of a 52-year-old womanwith a solitary meningeal relapse, a rare siteof recurrence, after 8 months of complete remissionobtained with M-VEC for locally advanced TCC ofthe bladder. We speculate on the likely riskfactors related to this unusual site of recurrence. 相似文献