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1.
Sci Total Environ ; 369(1-3): 246-55, 2006 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-16777189

RESUMO

Samples of silica-soda-lime float glass, a material selected as a pertinent soiling sensor, were exposed for up to 28 months at four urban sites (Athens, Krakow, London and Prague) and at a semi-urban one (Monte Libretti, near Rome), sheltered from rain. This exhaustive experience permitted to complete and to test the generalisation ability of the results previously obtained on the same material, exposed according to the same protocol, during 24 months, at a single site (Paris). The model previously fitted for the Paris experiment, the Hill equation, could be successfully generalised for four other sites of exposure (Athens, Krakow, Prague and Rome). The analytical form of this model was interpreted in terms of a physical description of the soiling phenomenon. Some of the model coefficients were different from one site to another, depending on the specific environment of exposure (air pollution levels, meteorological factors), while the other ones were rather equivalent. The analysis of the model coefficients, on the one hand, led to an estimation of the period after which soiling is close to its saturation level, and on the other hand, it will permit to correlate these coefficients to the environmental factors, in order to select the most appropriate ones for building dose-response functions for soiling, with broad geographical application.

2.
Forensic Sci Int ; 267: 60-65, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27552703

RESUMO

The quantification of ethylglucuronide (EtG) in hair is nowadays recognized as the approach with the highest diagnostic performance to evaluate harmful drinking. A widely accepted cut-off of 30pg/mg has been selected after several accurate compared studies. While most of the studies that were used to establish the appropriate cut-off value prescribed to cut hair into small segments before their extraction, hair milling has subsequently been identified as the most efficient pretreatment procedure and was therefore recommended in the last Consensus document issued by the Society of Hair Testing. In this study, we initially compared the results obtained with the two sample preparations, namely cutting and milling, both being applied to the same specimens (n=781). Among these, 205 samples produced measurable EtG values with both methods, with differences ranging from -41.7% up to +415% (the mean increase in EtG concentration, switching from cutting to milling, was +62.1% and the median was +42.3%). Among the aforementioned 205 samples, 29 specimens (3.7% of the total 781 samples) produced significantly different outcome, being classified as negative (i.e., below 30pg/mg) if the cutting procedure is used, but largely positive (above 40pg/mg) when milling is used. Subsequently, the positivity rates obtained on a large population dataset (>27,000 samples) with the two procedures, were retrospectively compared using variable cut-offs values. The percentage of head hair samples with EtG concentration exceeding 30pg/mg upon application of the milling procedure shows a 45% increase (from 10.9% to 15.8%) with respect to cutting procedure, whereas the fraction of hair samples with EtG exceeding 40pg/mg (10.5%) overlaps the percentage of positive samples obtained after cutting pretreatment and applying a cut-off of 30pg/mg. On the basis of these results, it would be worth considering the application of cut-off values linked with the pretreatment procedure, taking into account the results of forthcoming inter-laboratory calibrations.


Assuntos
Alcoolismo/diagnóstico , Glucuronatos/análise , Cabelo/química , Manejo de Espécimes/métodos , Detecção do Abuso de Substâncias/métodos , Biomarcadores/análise , Cromatografia Líquida , Toxicologia Forense , Humanos , Espectrometria de Massas , Reprodutibilidade dos Testes
3.
Environ Sci Pollut Res Int ; 22(23): 19170-83, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26250811

RESUMO

An approach consisting in combining in situ and laboratory experiments is often favoured for investigating the mechanisms involved in the weathering of the materials of the cultural heritage. However, the realistic simulation in the laboratory of the environmental conditions ruling the interactions of atmospheric compounds with materials is a very complex task. The aim of this work is to characterise CIME, a new chamber specially built to simulate the interactions between materials of the cultural heritage and the environment. The originality of this instrument is that beside the usual climatic parameters (temperature, relative humidity, solar radiation) and gaseous pollutants, it also allows the controlled injection of different types of particulate matter such as terrigenous, marine and anthropogenic. Therefore, varied realistic atmospheric environments (marine or urban) can be easily simulated within CIME. In addition to the technical description of CIME, this paper shows the first results obtained by the impact of gaseous pollutants on non-durable glass, bronze and limestone. The first experiments for the deposition of different particles (calcite, clays, soot and halite) are also presented.


Assuntos
Poluentes Atmosféricos/química , Teste de Materiais/instrumentação , Material Particulado/química , Ligas/química , Carbonato de Cálcio/química , Dióxido de Carbono/química , Carbonatos/química , Cidades , Cristalização , Vidro/química , Dióxido de Nitrogênio/química , Tamanho da Partícula , Fuligem/química , Estrôncio/química , Temperatura , Tempo (Meteorologia)
4.
Cardiovasc Pathol ; 6(4): 205-11, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25991537

RESUMO

Right ventricle endomyocardial biopsies were obtained from 13 thalassemic patients. Clinical profiles were investigated, and serum ferritin tests were assessed using diagnostic kits. Histochemical iron detection (Perls method) and immunohistochemical stain for ferritin were performed in the endomyocardial samples. Histologic iron overload was observed in eight patients, and variable iron deposits were recognized by a semiquantitative method. There was a statistically evident correlation between serum ferritin and myocardial iron storage. Marked iron deposition was associated with higher immunohistologic ferritin concentration. Iron-negative tissue samples showed bland immunohistochemical positivity. Myocardial interstitial fibrosis was observed in 12 cases; diffuse perimyocytic or perivascular fibrosis and endocardium thickening were the main histologic patterns identified. One biopsy was characterized by marked fibrolipomatous infiltration. Myocyte hypertrophy, myocytolysis, and severe capillary congestion also were observed.

5.
Ann Thorac Surg ; 26(5): 445-51, 1978 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-111640

RESUMO

A review of 20 consecutive patients with left main coronary artery stenosis operated on in 1976 indicated a general hemodynamic pattern characterized by systolic hypertension and an increase in heart rate that occurred early during the induction phase of anesthesia. From January through August, 1977, 28 patients with this stenotic condition were operated on with hemodynamic monitoring of left ventricular pressure and cardiac output by a Swan-Ganz catheter inserted before induction of anesthesia. Pharmacological interventions to optimize preload with volume, reduce afterload with nitroprusside or nitroglycerine, control heart rate with propranolol, and improve contractility with dopamine resulted in a decrease in mortality from 20% in Group 1 (1976) to 3.5% in Group 2 (1977). We conclude that control of systemic blood pressure, heart rate, and preload has notably reduced the mortality in this group of patients and that hemodynamic monitoring provides precise guidelines for therapeutic interventions.


Assuntos
Débito Cardíaco , Ponte de Artéria Coronária/métodos , Doença das Coronárias/diagnóstico , Monitorização Fisiológica , Contração Miocárdica , Adulto , Idoso , Pressão Sanguínea/efeitos dos fármacos , Débito Cardíaco/efeitos dos fármacos , Ponte de Artéria Coronária/mortalidade , Doença das Coronárias/mortalidade , Doença das Coronárias/fisiopatologia , Dopamina/uso terapêutico , Feminino , Frequência Cardíaca/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Contração Miocárdica/efeitos dos fármacos , Nitroglicerina/uso terapêutico , Nitroprussiato/uso terapêutico , Propranolol/uso terapêutico
6.
Ann Thorac Surg ; 24(4): 323-9, 1977 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-303080

RESUMO

The diagnosis of perioperative myocardial infarction (POMI) in patients undergoing coronary artery bypass is uncertain because the criteria of infarction are unclear. Fifty patients who underwent coronary artery bypass were evaluated preoperatively and postoperatively with serial ECGs, creatine phosphokinase (CPK), isoenzyme determinations, and technetium pyrophosphate myocardial scans. Clinical evaluation correlated with exercise testing and postoperative angiography supported the diagnosis in questionable cases. Thirty-five patients (70%) had no evidence of POMI by any criteria, and 2 patients (4%) had unequivocal evidence of infarction by all criteria. Our studies indicate the complexities of diagnosing POMI. We believe that the serially recorded ECG is the most useful diagnostic technique. CPK isoenzyme determinations may be useful but are difficult to interpret in the operative setting. Preoperative cardiac scans are necessary so as to avoid a high incidence of false-positive scans postoperatively. In doubtful cases, postoperative coronary arteriography and left ventricular angiography may provide the most definitive information.


Assuntos
Ponte de Artéria Coronária , Infarto do Miocárdio/diagnóstico , Complicações Pós-Operatórias/diagnóstico , Adulto , Idoso , Angiografia Coronária , Creatina Quinase/sangue , Diagnóstico Diferencial , Eletrocardiografia , Teste de Esforço , Feminino , Humanos , Isoenzimas/sangue , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/diagnóstico por imagem , Infarto do Miocárdio/enzimologia , Complicações Pós-Operatórias/sangue , Complicações Pós-Operatórias/diagnóstico por imagem , Cintilografia
7.
Health Psychol ; 6(5): 445-52, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-3678170

RESUMO

Stress-related physiological factors have been proposed to mediate the Type A behavior pattern (TABP) and coronary heart disease (CHD). However, collateral behavioral factors, such as the exaggerated consummatory response patterns of Type As, may also be involved. Study 1 examined this hypothesis by comparing exposure to cigarette smoke in 42 graduate and undergraduate student smokers assessed for the TABP. After controlling for smoking rate and Federal Trade Commission cigarette carbon monoxide yield, Type As' alveolar carbon monoxide (COa) levels were higher than Type Bs', and Jenkins Activity Survey scores were correlated with COa. To determine the source of this difference, we measured smoking topography in 10 Type As and 10 Type Bs in Study 2. Type As and Type Bs did not differ in number of puffs taken or puff volume, but Type As' inhalation duration was 70% longer than Type Bs'. These results suggest that consummatory behaviors of Type As may help account for the Type A-CHD relationship for smokers. Due to increased smoke exposure, Type A smokers may also be at greater risk for cancer and lung disease than Type B smokers.


Assuntos
Monóxido de Carbono/análise , Fumar , Personalidade Tipo A , Adolescente , Adulto , Comportamento Consumatório , Feminino , Humanos , Masculino , Respiração
8.
Physiol Behav ; 52(5): 839-41, 1992 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1484837

RESUMO

Although numerous studies have demonstrated reliable relationships between various human performance measures and time of day, disagreement exists concerning the shape of these relationships and their dependence on task variables. Most perceptual-motor tasks emphasize responsiveness to exteroceptive stimuli. We used a multiple force-band discrimination task that requires responsiveness to both exteroceptive and proprioceptive information. Results for a response duration measure showed a quadratic time of day trend similar to previously reported performance tasks. Response latency to the force emission cue and number of correct inband force emissions showed cubic time of day trends not typically reported in the time of day and performance literature. These results have implications for time-of-day effects on real world perceptual performance.


Assuntos
Ritmo Circadiano/fisiologia , Discriminação Psicológica/fisiologia , Temperatura Corporal/fisiologia , Humanos , Masculino , Propriocepção/fisiologia
9.
Physiol Behav ; 57(6): 1117-25, 1995 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7652032

RESUMO

The effects of caffeine (0 mg/kg, 1 mg/kg, 3 mg/kg) and time of day (TOD) on human performance were studied using a multiple forceband discrimination task (MFDT) and subjective ratings. Self-rated measures of energy level were affected by TOD and caffeine, while mood was affected by TOD. Energy level decreased throughout the day and was offset by caffeine which increased energy level independent of TOD. Self-reported anxiety was not affected by TOD or caffeine. Mood was affected by TOD in a complex cubic trend with late morning and late evening peaks 12 h apart. MFDT performance was affected by TOD, caffeine dosage, and their interaction. Trend analyses showed varying patterns of TOD effects across peak force variability, response latency, response duration, and correct responding. Results support and extend previous findings of TOD influences on the MFDT and support the utility of multicomponent proprioceptive tasks for examining drug effects on performance.


Assuntos
Cafeína/farmacologia , Ritmo Circadiano/fisiologia , Discriminação Psicológica/efeitos dos fármacos , Discriminação Psicológica/fisiologia , Adulto , Afeto/efeitos dos fármacos , Ansiedade/psicologia , Temperatura Corporal/efeitos dos fármacos , Relação Dose-Resposta a Droga , Força da Mão/fisiologia , Humanos , Masculino , Análise Multivariada
10.
Pharmacol Biochem Behav ; 36(2): 413-5, 1990 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2141424

RESUMO

This study investigated the effect of para-chlorophenylalanine (pCPA), on nicotine-induced analgesia. pCPA reduces physiological levels of 5-HT, a neurotransmitter that has been linked to pain. The effects of naloxone HCl and mecamylamine HCl on this analgesia were also assessed. Subjects were 24 albino rats. Each group of eight rats was injected subcutaneously (SC) with nicotine sulphate, followed by an intraperitoneal (IP) injection of one of the potential antagonists. Behavioral analgesia was assessed using the tail-flick test. Data analysis revealed that pCPA did not affect nicotine-induced analgesia. Consistent with past research, naloxone also had no effect, and mecamylamine effectively eliminated this analgesia. The results are interpreted in light of current knowledge of this behavioral analgesia and pain perception, in general.


Assuntos
Analgesia , Fenclonina/farmacologia , Nicotina/farmacologia , Dor/fisiopatologia , Animais , Interações Medicamentosas , Masculino , Mecamilamina/farmacologia , Naloxona/farmacologia , Ratos , Ratos Endogâmicos , Limiar Sensorial/efeitos dos fármacos
11.
Exp Clin Psychopharmacol ; 6(4): 406-18, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9861555

RESUMO

The hypothesis that smokeless tobacco-related sensory and behavioral cues can act as conditioned stimuli was tested in a counterbalanced double-blind experimental design. The nicotine content of snuff smokeless tobacco (ST) was manipulated for 24 male ST users by mixing ST with an ST substitute. Affect was manipulated through imagery scripts, stress was induced by a mental arithmetic task, and physiological measures and self-reported affect, stress, and urge for ST were collected. Urge for ST was consistently reduced regardless of the nicotine content in the ST conditions. Urge was increased by the stress manipulation and by negative affect when compared with positive affect. Urge for ST was positively correlated with stress and negative affect but was not correlated with positive affect. Physiological arousal was not related to urge. Results generally parallel studies of smoking and suggest that ST substitute products may aid ST cessation.


Assuntos
Afeto , Plantas Tóxicas , Estresse Fisiológico , Abandono do Uso de Tabaco/psicologia , Tabaco sem Fumaça , Adolescente , Adulto , Estudos Cross-Over , Sinais (Psicologia) , Relação Dose-Resposta a Droga , Método Duplo-Cego , Resposta Galvânica da Pele/efeitos dos fármacos , Frequência Cardíaca/efeitos dos fármacos , Humanos , Masculino
12.
Addict Behav ; 12(2): 195-8, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-3630806

RESUMO

Smokers report that smoking reduces anxiety. However, experimental research on the anxiety-reducing effects of smoking is limited to two self-report studies, both of which have methodological problems. We tested the effects of smoking on self-reported anxiety and avoidance behavior in a behavioral avoidance test (BAT) using a large white rat. In a counterbalanced within subjects design, 20 rat phobic female smokers smoked or were smoking deprived in two separate administrations of the BAT. A second group of 20 rat phobic nonsmokers also received two BATs. Subjects manifested substantial anxiety during BATs. However, neither smoking condition nor smoker versus nonsmoker status affected self-reported or motoric anxiety. Although smoking did not reduce anxiety in this study, smoking may affect anxiety in other situations, such as social settings, where the stimulus is more diffuse or less intense. It may also affect anxiety in individuals who are heavier smokers than our subjects, who smoked only 10-20 cigarettes per day.


Assuntos
Transtornos Fóbicos/psicologia , Fumar , Ansiedade/psicologia , Feminino , Humanos
13.
Addict Behav ; 11(3): 341-4, 1986.
Artigo em Inglês | MEDLINE | ID: mdl-3739820

RESUMO

Smoking reduces negative affect while it increases sympathetic nervous system activity. However, theories of emotion predict that increased autonomic arousal should increase rather than reduce negative affect. One explanation for this paradox is that nicotine interferes with perception of autonomic activity. We evaluated the effect of smoking on autonomic activity perception by measuring performance on a heartbeat detection task after a high or low dose of nicotine or not smoking. A group of nonsmokers also completed the task. Results failed to support the hypothesis. In light of previous research, the results suggest EMG perception may be more important to the negative affect reduction phenomenon than perception of autonomic activity.


Assuntos
Sistema Nervoso Autônomo/efeitos dos fármacos , Emoções/efeitos dos fármacos , Nicotina/farmacologia , Percepção/efeitos dos fármacos , Adolescente , Adulto , Feminino , Frequência Cardíaca/efeitos dos fármacos , Humanos , Propriocepção/efeitos dos fármacos , Tabagismo/psicologia
14.
Addict Behav ; 13(1): 87-90, 1988.
Artigo em Inglês | MEDLINE | ID: mdl-3364229

RESUMO

We tested the validity of the Fagerström Tolerance Questionnaire as a measure of physiological tolerance to nicotine. Both clinical and laboratory studies found neither the total questionnaire score nor the individual questionnaire items were related to physiological tolerance as measured by heart rate, skin conductance, blood volume pulse, and skin temperature responses to smoking a cigarette. We hypothesize the questionnaire measures behavioral dependence or perceived dependence rather than physical dependence.


Assuntos
Nível de Alerta/efeitos dos fármacos , Nicotina/farmacologia , Fumar/psicologia , Adulto , Pressão Sanguínea/efeitos dos fármacos , Tolerância a Medicamentos , Feminino , Resposta Galvânica da Pele/efeitos dos fármacos , Frequência Cardíaca/efeitos dos fármacos , Humanos , Masculino , Temperatura Cutânea/efeitos dos fármacos , Síndrome de Abstinência a Substâncias/psicologia
15.
Behav Modif ; 15(1): 113-7, 1991 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2003846

RESUMO

The only existing method of therapy supervision that provides on-line feedback to trainees is the "bug-in-the-ear," an auditory communication system. Although this system has several advantages over supervision strategies that use retrospective accounts, audio- and videotapes, and direct observation on sessions, it is disruptive to the trainee and must be limited to strategically timed three- or four-word communications. We describe and discuss advantages of the "bug-in-the-eye," an alternative to the bug-in-the-ear, which provides visual on-line feedback for therapist skill training.


Assuntos
Terapia Comportamental/educação , Ensino/métodos , Gravação de Videoteipe , Humanos , Microcomputadores , Sistemas On-Line , Rádio
16.
Environ Sci Pollut Res Int ; 21(15): 9251-8, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24723354

RESUMO

Glass materials are broadly used in the built environment (windows, facades, roofs, museum showcases, and solar panels) due to their optical (transparency) and thermal properties. Their interaction with the multiphase atmospheric medium results in a more or less pronounced transparency loss called soiling. This phenomenon leads to a loss of amenity of artefacts; consequently, high cleaning costs have to be supported by public and private entities. Complete understanding of the nature of surface deposit appears thus extremely important for addressing strategies to control it. The present research is based on the sheltered exposure, in different environments, of durable glass panels during 1 year. At these different locations, airborne pollutant concentrations have also been monitored. Three environments have been investigated: rural (R), urban (U) and industrial (I). Results show that the mass of the deposit and the optical impairment of the glass (haze) are too spread to allow discriminating between different environments. However, the analyses of soluble species and particulate organic matter allow identifying factors responsible for soiling and highlighted the reactivity of deposit to relative humidity which favours post-deposit evolution.


Assuntos
Vidro/química , Poluentes Atmosféricos/análise , Cidades , Meio Ambiente , Indústrias , População Rural
17.
Vet Immunol Immunopathol ; 148(3-4): 320-5, 2012 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-22608094

RESUMO

Tonsils are secondary lymphoid organs that play an important role in host defense. The aim of our study was to develop reliable procedures for isolation and culture of pig tonsil cells, and to validate their possible use in functional immunoassays. Using our isolation procedure, we recovered on average 238.7 ± 107.1 × 10(6) cells per tonsil couple with a mean vitality of 89.8 ± 2.7%. These values significantly decreased 8 months after freezing at -80°C along with the subsequent spontaneous release of both IgA and IgG in culture. These results suggest to use pig tonsil cells within 2 months from thawing to maintain suitable conditions in terms of recovery, vitality and release of antibody in vitro. Tonsil mononuclear cells also showed the ability to secrete antimicrobial peptides and to respond in vitro to immunological stimuli. On the whole, our study has defined operating conditions for tonsil processing, control of bacterial contaminations, time limits of storage at -80°C, as well as for evaluating polyclonal Ig production in vitro. Such procedures are likely to be of some importance in studies on regional immunity and in the development of large animal models for biomedical sciences.


Assuntos
Linfócitos/citologia , Tonsila Palatina/citologia , Suínos/imunologia , Animais , Linfócitos B/citologia , Linfócitos B/imunologia , Linfócitos B/fisiologia , Sobrevivência Celular , Células Cultivadas , Ensaio de Imunoadsorção Enzimática/veterinária , Citometria de Fluxo/veterinária , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/fisiologia , Linfócitos/imunologia , Linfócitos/fisiologia , Tonsila Palatina/imunologia
18.
Sci Total Environ ; 408(4): 976-84, 2010 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-19900698

RESUMO

Several exposure campaigns of silica-soda-lime window glass have been performed in 30 European sites and 1 in Canada in order to understand, quantify and model the phenomenon of soiling. In this purpose samples were exposed sheltered from the rain. Parallel to exposure, several meteorological parameters and pollution concentrations have been monitored. This paper shows first results on the establishment of a dose-response function for glass soiling. Statistical analyses show that PM(10) is not the only parameter, but also SO(2) and NO(2) atmospheric concentrations seem to be responsible for the optical impairment of glass surfaces, expressed as haze.


Assuntos
Poluentes Atmosféricos/química , Compostos de Cálcio/química , Materiais de Construção , Vidro/química , Óxidos/química , Dióxido de Silício/química , Hidróxido de Sódio/química , Tamanho da Partícula , Material Particulado/química , Propriedades de Superfície
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