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991.
Conti S Meli P Minelli G Solimini R Toccaceli V Vichi M Beltrano MC Perini L 《Igiene e sanità pubblica》2004,60(3):121-139
Following the unusually hot summer this year and the dramatic news from neighboring countries such as France, the Italian Minister of Health requested an epidemiologic mortality study during summer 2003, to investigate whether there had been an excess of deaths in Italy, particularly for the elderly population. Communal offices, which provide vital statistics, were asked for the number of deaths among resident people, occurred from June 1 to August 31, for 2003 and 2002, for the 21 Italian regions capitals. A mortality increase of 3,134 deaths was observed for 2003; most of them (92%) were people aged 75 years and older. The highest increases were observed in the North Western cities (Turin, Milan, Genoa). The relationship between mortality and climatic indexes (T. max, Humidex) was investigated and a clear correlation was observed. 相似文献
992.
The aim of the study is to investigate whether traffic policemen exposed to urban pollutants and psycho-social stressors may be at risk of modifications in serum levels of immunoglobulins G antibodies (IgG Ab) against Herpes Simplex Virus (type1) (HSV-1) compared with controls. Traffic policemen were matched by sex, age, working life and drinking habits (less than two glasses of wine or beer per day) with controls, after excluding the subjects with the principal confounding factors (smoking habit, use of paints, solvents, pesticides and drinking habits). Were included in the study 125 traffic policemen (54 men and 71 women) with outdoor activity and 125 controls (54 men and 71 women) with indoor activity. Mean levels of IgG Ab against HSV-1 were significantly higher in traffic policemen of both sexes compared with controls. The frequency of workers with IgG Ab against HSV-1 levels higher than our normal laboratory values, was significant in traffic policemen compared with controls of both sexes. The distributions of IgG Ab against HSV-1 levels in traffic policemen compared with controls of both sexes were significant. The authors hypothesise an effect of the working activity in traffic policemen on serum levels of IgG Ab against HSV-1 compared to controls. 相似文献
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996.
In mammals, the pineal hormone melatonin activates G protein-coupled MT(1) and MT(2) melatonin receptors. Acute exposure of recombinant MT(1) and MT(2) melatonin receptors to supraphysiological concentrations of melatonin differentially regulates these two receptors with the MT(2), but not the MT(1), exhibiting rapid desensitization and internalization. In the present study, we sought to determine whether prolonged exposure to supraphysiological and physiological concentrations of melatonin desensitized and/or internalized the MT(1) melatonin receptor. Using a Chinese hamster ovary (CHO) cell line stably expressing MT(1)-FLAG or transiently expressing MT(1)-green fluorescent protein (GFP) melatonin receptors, we found that prolonged exposure (8h) to supraphysiological concentrations of melatonin (100 nM) significantly increased the number of MT(1) melatonin receptors and decreased the affinity (K(i)) of melatonin for competition for 2-[125]iodomelatonin. A similar treatment also desensitized the MT(1) melatonin receptor-mediated stimulation of [(35)S]GTPgammaS binding, but did not internalize the receptor. In contrast, prolonged exposure to a concentration of melatonin mimicking nocturnal levels (400 pM) did not affect the number of MT(1) melatonin receptors, the affinity for melatonin, or the functional sensitivity of the receptor. We conclude that in vivo endogenous melatonin does not significantly affect the functional sensitivity of MT(1) melatonin receptors, however, exogenous melatonin taken therapeutically at doses above physiological levels could desensitize the receptor thereby affecting physiological responses mediated following activation of MT(1) melatonin receptors. 相似文献
997.
Stórustovu Sí Sánchez C Pörzgen P Brennum LT Larsen AK Pulis M Ebert B 《British journal of pharmacology》2004,142(1):172-180
1. Clinical observations with the selective serotonin reuptake inhibitor (SSRI), S-citalopram, indicate that S-citalopram is more efficacious and produces earlier symptom relief than RS-citalopram. Since R-citalopram is at least 20-fold weaker than S-citalopram as inhibitor of the 5-HT transporter (SERT) in preclinical studies, the clinical data suggest an unexpected antagonistic interaction between the two enantiomers. We therefore characterised the interaction of R- and S-citalopram with the SERT in in vivo and in vitro assays. 2. In both behavioural (potentiation of 5-hydroxytryptophan (5-HTP)-induced behaviour) and electrophysiological studies (inhibition of 5-HT-elicited ion currents in Xenopus oocytes expressing the human SERT (hSERT) R-citalopram inhibited the effects of S-citalopram in a dose-dependent manner. With S-citalopram : R-citalopram ratios of 1 : 2 and 1 : 4, 5-HTP potentiation was significantly smaller than with S-citalopram alone. 3. R-citalopram did not antagonise the effects of another SSRI (fluoxetine) in either behavioural or electrophysiological studies. 4. In oocytes, inhibition of hSERT-mediated currents by R-citalopram was almost completely reversible and characterised by fast on- and off-sets of action. In contrast, the off-set for S-citalopram was 35-fold slower than for R-citalopram. 5. Kinetic analysis of the oocyte experiments suggests that S-citalopram binding to SERT induces a long-lasting, inhibited state of the transporter and that coapplication of R-citalopram partially relieves SERT of this persistent inhibition. 6. We propose that the kinetic interaction of R- and S-citalopram with SERT is a critical factor contributing to the antagonistic effects of R-citalopram on S-citalopram in vitro and in vivo. 相似文献
998.
OBJECTIVE: Data from a large, nationally representative sample of hospital emergency departments (EDs) were used to assess the prevalence and characteristics of alcohol-related ED visits among people ages 13 to 25 years in the United States. METHOD: Emergency department visits recorded in the National Electronic Injury Surveillance System-All Injury Program were coded for alcohol involvement based on alcohol product codes and abstractions of chart narratives. National estimates and confidence intervals were calculated using SUDAAN statistical software. RESULTS: Based on these chart data, in the United States in 2001 there were an estimated 244,331 alcohol-related ED visits among people ages 13 to 25 (3.2% of total visits). Of these, an estimated 119,503 (49%) involved people below the legal drinking age of 21. The number of alcohol-related visits increased throughout adolescence and young adulthood to the age of 21, after which they decreased to levels similar to those seen for 18 to 20 year olds. Alcohol-related visits were most frequent on weekends and among males and were more strongly associated with visits related to assault or self-harm than to visits for unintentional injuries or injuries of unknown intent. In this population, 38% of alcohol-related visits involved no external cause of injury (e.g., drinking to excess only). CONCLUSIONS: These data highlight the need for stronger efforts to delay initiation of alcohol use among adolescents as long as possible and to limit access to alcohol for underage drinkers. 相似文献
999.
Recombinant human thyroid-stimulating hormone (rhTSH), used to enhance diagnostic radioiodine whole body scanning and thyroglobulin testing, has dramatically altered the management of patients with thyroid cancer. Withdrawal from thyroid hormone suppression therapy and subsequent hypothyroidism is no longer the only safe and effective method for thyroid cancer surveillance. Currently, rhTSH is only approved for the monitoring of low-risk patients with well-differentiated thyroid cancer and radioactive iodine administration, in selected cases. Additional applications of rhTSH include enhancing the sensitivity of positron emission tomography in thyroid cancer, the management of multinodular goiter, and dynamic testing of thyroid reserve. The diagnostic and therapeutic role of rhTSH in these areas is discussed in this review. 相似文献
1000.
Marongiu B Porcedda S Piras A Rosa A Deiana M Dessì MA 《Phytotherapy research : PTR》2004,18(10):789-792
The antioxidant activity of Melissa officinalis subsp. officinalis and of Melissa officinalis subsp. inodora extracts, obtained by using carbon dioxide under supercritical conditions was investigated. The samples were prepared in two steps. A preliminary extraction at 90 bar and 50 degrees C eliminated the essential oil, then a further extraction at 300 bar and 50 degrees C obtained the high molecular mass extract. These samples were tested for autoxidation and the iron or EDTA-mediated oxidation of linoleic acid at 37 degrees C in the absence of solvent, in in vitro systems. During linoleic acid autoxidation and its EDTA-mediated oxidation both M. officinalis and M. inodora extracts showed an antioxidant activity, and no significant differences in their efficacy were observed. None showed any prooxidant activity. 相似文献