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1.
J Environ Manage ; 238: 10-17, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-30836280

RESUMO

Over the last decade there has been a significant boost towards the use of electronic cigarettes (e-cigarettes), especially among youth. Different concentrations of propylene glycol (PG) or vegetable glycerin (VG), flavors and nicotine are mixed in plastic cartridges and commercially offered or privately produced by the vapers. During vaping, a mixture of air and vapors is inhaled to the lungs. Since the ingredients of the e-cigarettes are not burned but vaporized (heated), fewer chemicals are emitted. The levels of potentially toxic compounds (e.g. volatile organic compounds (VOCs), particulate matter (PM), metals, radicals, nitrosamines, etc.) emitted from vaping appear to be lower compared to that of tobacco smoking (from combustible cigarettes). Nevertheless, measurable toxic elements and VOCs are still released (e.g. acetaldehyde, formaldehyde, acrolein, benzene, etc.) along with other volatiles associated with e-liquid flavoring and device variability with PG and VG. The wide range of available flavors at various purities along with the heating temperature are important parameters affecting the evolution of VOCs and aerosols. There is lack of standardized short- and long-term epidemiological medical data (chronic exposure) on e-cigarettes effects to users, non-users and the human micro-environment (second- or third-hand exposure). Therefore, the potential health, safety and environmental effects of vaping are reviewed, examined and discussed.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina , Aerossóis , Humanos , Nicotina , Material Particulado , Rios
2.
Environ Pollut ; 348: 123765, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38503351

RESUMO

Indoor air quality (IAQ) is critical to the health and wellbeing of people. As the majority of people spend greater amounts of time indoors, either in office spaces or households, the level of air pollutants in such environments is critical. Building materials and furniture are known sources of air pollutants such as Volatile Organic Compounds (VOCs) and may be associated with discomfort, detrimental health of the occupants, etc. In this study, the VOCs found in a brand new office complex were monitored over a period of 6 months, with an emphasis on monitoring and quantifying harmful VOCs and identifying their emission source. Air samples were taken from a closed, unoccupied office space on a weekly basis and analysed using Thermal Desorption-Gas Chromatography-Mass Spectrometry (TD-GC-MS), while continuous monitoring of the air quality was performed using two commercially available IAQ sensors. To identify the source of the emitted VOCs, pieces of all construction material that were used in the office, including flooring, finished wall material, and adhesive glues, were removed, and placed in air-tight glass containers prior to analysis confirming that the source of VOCs is indeed the flooring. Identified compounds included mainly material origin VOCs such as BTEX (benzene, toluene, ethylbenzene, xylene) and styrene, but also common VOCs such as acetone and propan-2-ol. Of significant importance was the concentration of toluene that was found to be the most abundant VOC in both the flooring material and the indoor air.


Assuntos
Poluentes Atmosféricos , Poluição do Ar em Ambientes Fechados , Compostos Orgânicos Voláteis , Humanos , Compostos Orgânicos Voláteis/análise , Monitoramento Ambiental/métodos , Cromatografia Gasosa-Espectrometria de Massas , Poluentes Atmosféricos/análise , Materiais de Construção , Poluição do Ar em Ambientes Fechados/análise , Tolueno/análise
4.
Water Sci Technol ; 61(3): 581-9, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20150693

RESUMO

The aim of this work is to examine copper removal from sludge permeate with the use of low-cost minerals of Mediterranean origin combined with ultrafiltration membranes. The minerals used were zeolite (clinoptilolite), bentonite and vermiculite. Activated sludge was enriched with 0.01 N (317.7 ppm) of Cu(II). Fixed concentrations of minerals were added to sludge and the pH value was adjusted at 5.5. The mixture was agitated for 2 hours at 800 rpm at room temperature and was then filtered through a batch ultrafiltration system for 1 hour. This experiment was repeated, for comparison purposes, with sludge enriched with 0.01 N of Cu(II) with no mineral addition. The results showed that ultrafiltration membranes with no mineral addition were able to remove a significant amount of copper with removal efficiencies ranging from 59.4-78.3%. The addition of 10 g/l and 20 g/l of bentonite combined with ultrafiltration membranes resulted in removal efficiencies of 94.9% and 99.4% respectively and that of 10 g/l and 20 g/l of vermiculite in removal efficiencies of 93.8% and 96.8%, respectively. The ion exchange capacity of minerals followed the order bentonite > vermiculite > zeolite. Furthermore, membrane fouling was investigated. The addition of zeolite and bentonite reduced membrane fouling, while the addition of vermiculite did not impact on fouling. The use of low-cost minerals in combination with ultrafiltration membranes can be employed to treat industrial wastewater, resulting in a final effluent with very low copper concentrations.


Assuntos
Cobre/isolamento & purificação , Esgotos/análise , Adsorção , Ar , Silicatos de Alumínio , Bentonita , Concentração de Íons de Hidrogênio , Resíduos Industriais , Ultrafiltração/instrumentação , Ultrafiltração/métodos , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/isolamento & purificação , Zeolitas
5.
Artigo em Inglês | MEDLINE | ID: mdl-32920481

RESUMO

Solid phase micro extraction-Gas Chromatography/Mass Spectrometry (SPME-GC/MS) analysis was performed in exhaled breath samples of 48 healthy volunteers: 20 non-smokers, 10 smokers and 18 e-cigarette (EC, vape) users. Each volunteer provided 1 L of exhaled breath in a pre-cleaned Tedlar bag, in which an SPME fiber was exposed to absorb the emitted breath volatile organic compounds (VOCs). The acquired data were processed using multivariate data analysis (MDA) methods in order to identify the characteristic chemicals of the three groups. The results revealed that the breath of non-smokers demonstrated inverse correlation with a variety of molecules related to the breath from smokers including furan, toluene, 2-butanone and other organic substances. Vapers were distinguished from smokers by the chemical speciation of the e-liquids, such as that of esters (e.g. ethyl acetate), terpenes (e.g. α-pinene, ß-pinene, d-limonene, p-cymene, etc.) and oxygenated compounds (e.g. 3-hexen-1-ol, benzaldehyde, hexanal, decanal, etc). Two classification models were developed (a) using principal component analysis (PCA) with hierarchical cluster analysis (HCA) and (b) using partial least squares-discriminant analysis (PLS-DA). Both models were validated using 8 new samples (4 vapers and 4 smokers), collected in addition to the 48 samples of the calibration set. The combination of GC/MS breath analysis and MDA contributed successfully in classifying the volunteers into their respective groups and highlighted the relevant characteristic VOCs. The respective dynamic combination (SPME-GC/MS and MDA) provides a means for long term non-invasive monitoring of the population's health status for early detection purposes.


Assuntos
Testes Respiratórios/métodos , Fumar Cigarros/metabolismo , Cromatografia Gasosa-Espectrometria de Massas/métodos , Vaping/metabolismo , Compostos Orgânicos Voláteis/análise , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , não Fumantes , Fumantes , Microextração em Fase Sólida/métodos , Adulto Jovem
6.
Sarcoidosis Vasc Diffuse Lung Dis ; 26(2): 121-31, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20560292

RESUMO

BACKGROUND: Agents that target pro-inflammatory cytokines may be useful in pulmonary sarcoidosis. OBJECTIVE: To determine effectiveness of a non-selective cyclic nucleotide phosphodiesterase (PDE) inhibitor, pentoxifylline (POF). DESIGN: Randomized, double-blind, placebo-controlled trial, SETTING: Clinical Research Center, National Institutes of Health. PATIENTS: 27 patients with biopsy-confirmed pulmonary sarcoidosis receiving prednisone. INTERVENTION: Placebo or POF (1200-2000 mg/day) for 10 months, as prednisone was tapered. MEASUREMENTS: Primary endpoints: sustained improvement in two or more pulmonary function parameters, or a combination of one pulmonary function parameter and dyspnea. RESULTS: Except for one patient, primary endpoints were not reached in POF-treated patients. Therefore, a post hoc analysis was performed. The observed relative risk reduction for flares associated with POF treatment was 54.9% (95% CI 0.21, 0.89) and the absolute risk reduction was 50.6% (95% CI 0.22, 0.80). Compared to placebo treatment, in the POF group, the mean prednisone dose was lower at 8 and 10 months (p = 0.007 and 0.01 respectively), and there was a trend towards less prednisone usage over the entire study period (p = 0.053), as determined by cumulative change analysis. CONCLUSIONS: Although our exploratory post hoc analysis suggested that POF reduced flares and had steroid-sparing effects, given the study limitations, definitive conclusions cannot be drawn regarding the efficacy of POF in pulmonary sarcoidosis. In addition, gastrointestinal side-effects, at the doses used, would seem to limit the use of POF in treating pulmonary sarcoidosis. Overall, however, this trial may provide a basis for using more specific, better-tolerated, PDE inhibitors in future clinical trials.


Assuntos
Hipertensão Pulmonar/tratamento farmacológico , Pentoxifilina/uso terapêutico , Inibidores de Fosfodiesterase/uso terapêutico , Adolescente , Adulto , Idoso , Biópsia , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Fluxo Expiratório Forçado/efeitos dos fármacos , Humanos , Hipertensão Pulmonar/patologia , Hipertensão Pulmonar/fisiopatologia , Masculino , Pessoa de Meia-Idade , Pentoxifilina/administração & dosagem , Inibidores de Fosfodiesterase/administração & dosagem , Testes de Função Respiratória , Resultado do Tratamento , Adulto Jovem
7.
Waste Manag ; 29(1): 204-13, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18558483

RESUMO

This article presents the methodology and the results of the performance testing of a prototype system for the production of high quality compost from biodegradable household waste separated at the source. Selected households in three municipalities of the Attica Region in Greece constituted the users of the home composter. The results indicated the effective operational performance of the prototype household composter in practice (use of the system by the householders on a daily basis), as well as the high level of response of the householders in adopting the composting practice in their daily activities as common practice. The compost that was produced in the households was characterized by high quality, which is in accordance with the quality standards that are set for its use. In only a few cases (in the first cycle of the pilot implementation) the quality of the compost was not high due to the fact that some householders were not yet familiar with the use of the composter, but these operational problems were solved and the compost that was later produced was considered high quality.


Assuntos
Características da Família , Eliminação de Resíduos/métodos , Solo , Carbono , Conservação dos Recursos Naturais/métodos , Coleta de Dados , Concentração de Íons de Hidrogênio , Nitrogênio , Projetos Piloto , Inquéritos e Questionários , Água
8.
J Biomol Screen ; 13(5): 354-62, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18467669

RESUMO

Measurement of intracellular calcium release following agonist challenge within cells expressing the relevant membrane protein is a commonly used format to derive structure-activity relationship (SAR) data within a compound profiling assay. The Fluorometric Imaging Plate Reader (FLIPR) has become the gold standard for this purpose. FLIPR traditionally uses cells that are maintained in continuous culture for compound profiling of iterative chemistry campaigns. This supply dictates that assays can only be run on 4 of 5 weekdays, or alternative cell culture machinery is required such that plating can occur remotely at the weekend. The data reported here demonstrate that high-quality compound profiling data can be generated from the use of cryopreserved cells and that these cells can also be plated at various densities to generate equivalent data between 24 and 72 h post-plating. Hence, the authors report a method that allows data generation throughout the week and without the requirement of highly automated cell culture or continuous culture.


Assuntos
Cálcio/análise , Criopreservação , Fluorometria/métodos , Animais , Células CHO , Cálcio/metabolismo , Cricetinae , Cricetulus , Fluorometria/instrumentação , Humanos , Relação Estrutura-Atividade
9.
Anticancer Res ; 28(1A): 245-51, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18383852

RESUMO

BACKGROUND: The major proteoglycan of normal human larynx is aggrecan. In laryngeal carcinoma, aggrecan is depleted, with versican and decorin appearing in higher amounts. MATERIALS AND METHODS: Proteoglycans in laryngeal carcinoma samples were characterized immunohistochemically and using Western blotting; their expression was examined by RT-PCR. RESULTS: Aggrecan was totally removed in advanced cancer and its RT-PCR product was not identified. Both versican and decorin were overexpressed in cancer, versican much more than decorin. Decorin expression was higher than that of versican in the normal larynx; therefore, their disproportionate overexpression during cancer resulted in about equimolar expression. Both proteoglycans' expression correlated with their stage-related accumulation within the tissue. CONCLUSION: These data add to our previous findings and support the view that the levels of expression and the extent of accumulation and localization in the tumor stroma of structurally modified versican and decorin could be associated with the degree of aggressiveness of laryngeal carcinoma.


Assuntos
Carcinoma de Células Escamosas/metabolismo , Proteínas da Matriz Extracelular/biossíntese , Neoplasias Laríngeas/metabolismo , Proteoglicanas/biossíntese , Versicanas/biossíntese , Adulto , Idoso , Idoso de 80 Anos ou mais , Agrecanas/biossíntese , Agrecanas/genética , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patologia , Decorina , Proteínas da Matriz Extracelular/genética , Humanos , Imuno-Histoquímica , Neoplasias Laríngeas/genética , Neoplasias Laríngeas/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Proteoglicanas/genética , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Versicanas/genética
10.
Biomed Res Int ; 2018: 8790283, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29662903

RESUMO

There have been calls to test the potential benefits of different forms of physical activity (PA) to executive function, particularly in authentic settings. Hence, the purpose of this study was to investigate the effect of an acute dance session within an existing physical education class on students' selective attention. The study employed a pre/posttest quasi-experimental design with a comparison group in one Aotearoa, New Zealand, primary school. Participants were 192 students (comparison group = 104 students) in Years 5 and 6. The intervention group participated in a dance-based physical education lesson while the comparison group continued their regular classroom work. PA during the physical education lesson was monitored using accelerometers. Selective attention was assessed at pretest and after the comparison/physical education sessions with the d2 Test of Attention. 2 × 2 ANOVA results suggested a significant time effect for all three measures, no significant group effects for any measures, and significant time by group interactions for TN and CP but not for E%. The intervention group improved significantly more than the comparison group for TN and CP. This study's findings suggest that existing school opportunities focused on cognitively engaging PA, such as dance, can improve aspects of students' selective attention.


Assuntos
Atenção , Dança , Educação Física e Treinamento , Instituições Acadêmicas , Estudantes , Análise de Variância , Criança , Exercício Físico , Feminino , Humanos , Masculino , Nova Zelândia
11.
Dalton Trans ; 46(11): 3688-3699, 2017 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-28256650

RESUMO

A new two-electron photosensitizer, H2BBQ2+[ZnCl4]2-/[(ZnCl)2(µ-BBH)] (BBQ stands for 2,5-bis[bis(pyridin-2-ylmethyl)amino]-1,4-quinone and BBH stands for 2,5-bis[bis(pyridin-2-ylmethyl)amino]-1,4-hydroquinone), has been synthesized and the oxidation state of the ligand was determined by X-ray crystallography and NMR spectroscopy. Under light illumination the H2BBQ2+[ZnCl4]2- + ZnCl2 is reduced quantitatively to [(ZnCl)2(µ-BBH)] (pH ∼ 5) oxidizing H2O to H2O2 as is evident by trap experiments. Electrochemistry gave a reversible two-electron ligand-centered redox wave for [(ZnCl)2(µ-BBH)]. UV-Vis, luminescence and EPR spectroscopies reveal the slow formation of a stable quinone diradical, intermediate of the reaction. DFT calculations are in agreement with the proposed mechanism. Based on this property an aqueous {[(ZnCl)2(µ-BBH)]||H2O2} solar rechargeable galvanic cell has been constructed.

13.
Acad Radiol ; 2(3): 222-5, 1995 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9419552

RESUMO

RATIONALE AND OBJECTIVES: Most radiologists are familiar with the classic chest radiographic findings of cystic fibrosis (CF) when these occur in children. We hypothesized that given the same findings, a diagnosis of CF would be less likely to be considered in an adult than in a child. METHODS: We compiled 30 pediatric and 28 adult CF chest radiographs and obtained two independent readings on each by different general radiologists among the eight who volunteered to participate as they performed their daily clinical work. The cases were presented to the readers so that they did not know which radiographs were part of the study. The association between the correct diagnosis of CF and whether the patient was an adult or a child was assessed using odds ratios and logistic regression, so that Brasfield score, Schwachman-Kulczycki score, and the patient's sex could also be considered as predictive of correct diagnosis. RESULTS: In 67% of the pediatric cases, at least one of the radiologists considered CF as a possible diagnosis, whereas they considered CF a possibility in only 50% of the adults. Both radiologists suggested the correct diagnosis in 40% of pediatric cases and only 14% of adult cases (p < .05). CONCLUSION: Because the radiographic findings were similar in the two groups of patients according to severity groupings, we believe CF was less commonly considered in the adult patient because of the traditional belief that CF is a childhood disease.


Assuntos
Fibrose Cística/diagnóstico por imagem , Adolescente , Adulto , Distribuição de Qui-Quadrado , Criança , Pré-Escolar , Fibrose Cística/classificação , Diagnóstico Diferencial , Feminino , Humanos , Modelos Logísticos , Masculino , Variações Dependentes do Observador , Valor Preditivo dos Testes , Radiografia Torácica
14.
Acta Otolaryngol ; 122(3): 330-7, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12030585

RESUMO

Glycosaminoglycans in normal and cancerous human laryngeal cartilage were isolated and characterized by means of enzyme susceptibility and high performance liquid chromatography. The known mammalian glycosaminoglycans were identified in all samples but their content and composition varied between normal and malignant samples. Chondroitin/dermatan sulphate was the major glycosaminoglycan in all cases, but its relative proportion was decreased in malignant samples. Its sulphation pattern showed that in normal samples it was sulphated mainly at the C6 position of galactosamine, whereas in malignant samples it was sulphated mainly at C4. Dermatan sulphate, expressed as a result of the different digestion of samples with chondroitinases, was present in very small amounts in normal samples (2.7% of total sulphated glycosaminoglycans) but increased in proportion up to 27.7% in malignant samples. The content of oversulphated chondroitin/dermatan was increased twofold in malignant samples. The content of heparan sulphate was increased almost fivefold in malignant samples as compared to normal ones. The content of hyaluronan was increased in malignant samples 3.5-fold, amounting to up to 11.4% of total glycosaminoglycans. These dramatic changes in the content and composition of glycosaminoglycans seemed to be characteristic of the tumour and independent of its status.


Assuntos
Carcinoma de Células Escamosas/metabolismo , Glicosaminoglicanos/metabolismo , Neoplasias Laríngeas/metabolismo , Condroitina/metabolismo , Cromatografia Líquida de Alta Pressão , Cromatografia por Troca Iônica , Dermatan Sulfato/metabolismo , Humanos , Cartilagens Laríngeas/metabolismo , Masculino , Pessoa de Meia-Idade
15.
Biochimie ; 95(4): 725-34, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23131589

RESUMO

Members of the ADAMTS family of proteases degrade proteoglycans and thereby have the potential to alter tissue architecture and regulate cellular functions. Aggrecanases are the main enzymes responsible for aggrecan degradation, due to their specific cleavage pattern. In this study, the expression status, the macromolecular organization and localization of ADAMTS-1, ADAMTS-4/aggrecanase-1 and ADAMTS-5/aggrecanase-2 in human normal larynx and laryngeal squamous cell carcinoma (LSCC) were investigated. On mRNA level, the results showed that ADAMTS-4 was the highest expressed enzyme in normal larynx, whereas ADAMTS-5 was the main aggrecanase in LSCC presenting a stage-related increase up to stage III (8-fold higher expression compared to normal), and thereafter decreased in stage IV. Accordingly, immunohistochemical analysis showed that ADAMTS-5, but not ADAMTS-4, was highly expressed by carcinoma cells. Sequential extraction revealed an altered distribution and organization of multiple molecular forms (latent, activated and fragmented forms) of the enzymes within the cancerous and their corresponding macroscopically normal laryngeal tissues, compared to the normal ones. Importantly, these analyses indicated that critical macromolecular changes occurred from the earliest LSCC stages not only in malignant parts of the tissue but also in areas that were not in proximity to carcinoma cells and appeared otherwise normal. Overall, the results of the present study show that ADAMTS-5/aggrecanase-2 is the main aggrecanase present in laryngeal carcinoma suggesting a critical role for the enzyme in aggrecan degradation and laryngeal tissue destruction during tumor progression.


Assuntos
Proteínas ADAM/genética , Proteínas ADAM/metabolismo , Regulação Neoplásica da Expressão Gênica , Neoplasias Laríngeas/enzimologia , Neoplasias Laríngeas/genética , Laringe/metabolismo , Proteína ADAMTS1 , Proteína ADAMTS4 , Proteína ADAMTS5 , Idoso , Carcinoma de Células Escamosas/enzimologia , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Feminino , Humanos , Neoplasias Laríngeas/metabolismo , Laringe/enzimologia , Masculino , Pró-Colágeno N-Endopeptidase/genética , Pró-Colágeno N-Endopeptidase/metabolismo , Transporte Proteico , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
18.
Waste Manag Res ; 26(3): 267-75, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18649575

RESUMO

This paper refers to the management of the construction and demolition (C&D) waste since, according to the EU Waste Strategy, C&D waste is considered to be one of the priority waste streams and appropriate actions need to be taken with respect to its effective management. Initially, the paper presents the state-of-the-art of the problem of C&D waste, including the amount and composition of C&D waste in EU countries, differences in the characteristics of this waste stream depending on its origin, as well as collection and management practices that are applied. A methodology is described for the estimation of the quantities of the waste stream under examination, since in most cases quantitative primary data is not available. Next, the fundamentals for the development of an integrated scheme for the management of C&D waste are presented and discussed, such as appropriate demolition procedures and location of waste management (off-site waste management, on-site waste management, direct on-site recovery, centralized on-site recovery). Finally, taking into consideration all relevant parameters, alternative systems that could be applied for the management of the C&D waste are suggested.


Assuntos
Materiais de Construção , Explosões , Gerenciamento de Resíduos/métodos , União Europeia
19.
Epidemiol Infect ; 107(3): 685-91, 1991 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1661242

RESUMO

Neutralizing antibodies to sandfly fever Naples, sandfly fever Sicilian and Toscana viruses were investigated among 479 sera collected from a normal human population in Cyprus. Antibody prevalence rates of 57%, 32% and 20% were found to Naples, Sicilian and Toscana viruses, respectively. The observed frequency of dual and triple infections was higher than would be expected with a random chance of infection. Antibody prevalence rates were similar for men and women for all three viruses tested, but one of two study sites had significantly higher antibody prevalence to Naples and Sicilian viruses than the other. Individuals with antibodies to both Naples and Toscana viruses had higher antibody levels to Naples virus than those with antibodies to Naples virus only. If the antibody prevalence rates found in this study reflect a history of clinical disease as described in the literature, sandfly fever poses a significant public health problem in Cyprus.


Assuntos
Anticorpos Antivirais/sangue , Febre por Flebótomos/epidemiologia , Phlebovirus/imunologia , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Chipre/epidemiologia , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Prevalência
20.
Stat Med ; 12(5-6): 543-51; discussion 553, 1993 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8493430

RESUMO

A targeted poll was undertaken to compare and contrast models of data monitoring of randomized clinical trials sponsored by the National Institutes of Health. In an attempt to represent the institutes which conduct clinical trials, twelve individuals were selected and asked to respond to a questionnaire specifically prepared for this workshop. The response rate was 100 per cent. Most of the large trials sponsored by the institutes have independent, formally constituted data monitoring committees. There was one institute which does not have any data monitoring committees. The questionnaire is described in detail and a summary of the results is given.


Assuntos
Ensaios Clínicos como Assunto/normas , Humanos , National Institutes of Health (U.S.) , Comitê de Profissionais , Estatística como Assunto , Inquéritos e Questionários , Estados Unidos
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