RESUMO
Click thiol-ene chemistry is demonstrated for the reaction of thiol containing molecules with surface alkene bonds during electrical discharge activation. This plasmachemical reaction mechanism is shown to be 2-fold for allyl mercaptan (an alkene and thiol group containing precursor), comprising self-cross-linked nanolayer deposition in tandem with interfacial cross-linking to the surface alkene bonds of a polyisoprene base layer. A synergistic multilayer structure is attained which displays high wet electrical barrier performance during immersion in water.
RESUMO
The cause of the difference in the mean tolerance (ED50) to cortisone-induced cleft palate between the embryos of the A/J and C57BL/6J strains appears to be due to a small number of genes. A single major gene effect and a polygenic model, in the sense of many equal and additive genes, have been ruled out. The embryonic tolerance of C57BL/6J is greater than and dominant to that of A/J; two or three loci, possibly with independent effects, appear to explain the variability. A component of the variation in embryonic response may be associated with or linked to the major histocompatibility locus (H-2). No evidence was found to support the hypothesis of X-chromosome linked susceptibility to cortisone-induced cleft palate.
Assuntos
Anormalidades Induzidas por Medicamentos/genética , Fissura Palatina/induzido quimicamente , Cortisona , Genes/efeitos dos fármacos , Animais , Mapeamento Cromossômico , Fissura Palatina/genética , Feminino , Ligação Genética , Variação Genética , Genótipo , Antígenos HLA , Masculino , Camundongos , Camundongos Endogâmicos , Probabilidade , Cromossomos SexuaisRESUMO
The uptake of tritiated thymidine by isolated peripheral blood lymphocytes obtained from male guinea pigs immunized with bovine serum albumin was studied in animals maintained on various amounts of Vitamin C for 28 days. Animals were pair-fed on ascorbate-free diet and were supplemented intraperitoneally with 0, 25, or 250 mg Na-ascorbate per day. Scorbutic animals lost weight rapidly during the final 2 experimental weeks. Their daily food intake averaged only 4 g/day during the last week; thus, pair-fed ascorbate-supplemented groups were also subjected to acute nutritional stress. Lymphocytes from guinea pigs receiving 250 mg Na-ascorbate per day incorporated in vitro the highest amounts of tritiated thymidine both in the absence of nonspecific mitogen and in the presence of concanavalin A or phytohemagglutinin. Responses to lipopolysaccharide were not conclusive. Total circulating white cells counts and relative numbers of T and B lymphocytes were assessed in a second study made under identical constraints. In scorbutic animals the percentage of B lymphocytes increased and that of T lymphocytes decreased continuously over the 4-week period. The opposite effect was observed in vitamin C-supplemented animals. These studies suggest that very high doses of ascorbate support elevated mitotic activity after 4 weeks of much reduced food intake.
Assuntos
Ácido Ascórbico/farmacologia , Imunidade Celular/efeitos dos fármacos , Linfócitos/imunologia , Animais , Ácido Ascórbico/metabolismo , Concanavalina A/farmacologia , Relação Dose-Resposta a Droga , Cobaias , Contagem de Leucócitos , Lipopolissacarídeos/farmacologia , Linfócitos/efeitos dos fármacos , Linfócitos/fisiologia , Masculino , Mitose , Fito-Hemaglutininas/farmacologia , Timidina/metabolismo , Distribuição TecidualRESUMO
Malfunction of a prosthetic mitral disc valve was clinically suspected on the basis of absent valve closing sound and an early opening click in a patient with first-degree atrioventricular (A-V) block. Premature closure and opening of the prosthetic valve was demonstrated by echocardiography. All abnormal auscultatory, phonocardiographic, and echocardiographic findings disappeared promptly upon spontaneous restoration of normal A-V conduction. The possible hemodynamic mechanism is discussed, and attention is drawn to this conduction abnormality as a cause of erroneous diagnosis of prosthetic mitral valve malfunction.
Assuntos
Bloqueio Cardíaco/complicações , Próteses Valvulares Cardíacas/efeitos adversos , Insuficiência da Valva Mitral/etiologia , Estenose da Valva Mitral/cirurgia , Adulto , Ecocardiografia , Eletrocardiografia , Feminino , Sistema de Condução Cardíaco/fisiopatologia , Ruídos Cardíacos , Humanos , Valva Mitral/fisiopatologia , Insuficiência da Valva Mitral/fisiopatologia , Fonocardiografia , Pulso ArterialRESUMO
A patient with the left coronary artery isolated from the ascending aorta is discussed. This is the seventh case described and the third diagnosed preoperatively. In contrast to other patients she had predominant aortic incompetence and was much older (52 years compared with the other patients, all younger than 25 years). She also had two angiograms demonstrating progressive isolation of the coronary artery with time. The patient was managed by aortic valve replacement. It is our belief that the condition is acquired and resulted from fusion of the free edge of the aortic valve leaflet to the supravalvar ridge secondary to an inflammatory process.
Assuntos
Doenças da Aorta/patologia , Doença das Coronárias/patologia , Aorta/anormalidades , Doenças da Aorta/etiologia , Doenças da Aorta/cirurgia , Doença das Coronárias/etiologia , Doença das Coronárias/cirurgia , Anomalias dos Vasos Coronários/patologia , Feminino , Humanos , Pessoa de Meia-IdadeRESUMO
BACKGROUND: An acceptable assessment must be both valid and reliable; the face validity of the Leicester assessment package has already been established. AIM: This study set out to test the reliability of the Leicester assessment package, and the factors influencing it, when used by multiple assessors to assess performance in general practice consultations. METHOD: Six randomly selected course organizer assessors simultaneously used the package to conduct independent assessments of the performance of five doctors of widely varying abilities in consultation with six simulated patients. The scores allocated were subjected to generalizability analysis. RESULTS: The mean scores allocated for consultation performance of individual doctors ranged from 51% to 70%, with the lower scores being allocated to the less experienced doctors. Scores of each assessor across the cases were examined for internal consistency and five of the six assessors consistently scored the doctors with an alpha coefficient of the minimum accepted level of 0.80 or greater. The other assessor had a consistency of only 0.22. Measurements of consistency within cases between markers indicated that the first case produced unreliable results (alpha coefficient 0.25) but all other cases were scored consistently. Two independent assessors scoring eight consultations are the requisite numbers to achieve acceptable levels of reliability in a formal assessment process; seven consultations produce the minimum acceptable generalizability coefficient of 0.80 plus the first 'non-counting' consultation. CONCLUSION: Required levels of reliability can be achieved when the package is used by multiple markers assessing the same consultations over a wide range of consultation performance. To achieve reliability only two hours of assessment time are required using the Leicester package compared with the previously regarded minimum of 32 hours. Although assessors can produce reliable scores with minimal training, intra-assessor reliability cannot be taken for granted and all assessors should be trained and calibrated before being sanctioned to conduct assessments, particularly for regulatory purposes. The Leicester assessment package has now been shown to be valid, reliable, feasible and easy to use in practice. It can, therefore, be recommended for use in both formative and summative assessment of consultation competence in general practice.
Assuntos
Medicina de Família e Comunidade , Relações Médico-Paciente , Competência Profissional , Comunicação , Humanos , Simulação de Paciente , Distribuição Aleatória , Encaminhamento e Consulta , Reprodutibilidade dos TestesRESUMO
AIM: This study set out to test the face validity of prioritized criteria of consultation competence in general practice as contained in the Leicester assessment package. METHOD: A questionnaire was sent to a geographically stratified random sample of 100 members of the United Kingdom Association of Course Organisers to seek their views on the categories, components and weightings contained in the Leicester assessment package and to determine the proportion of respondents who rejected or suggested a new category, component or weighting or reallocated components to other categories or amended weightings. Their views were sought on a six-point scale (strongly approve, approve, tend to approve, tend to disapprove, disapprove and strongly disapprove). RESULTS: There was a 73% response rate. Of the respondents 99% either strongly approved or approved of the overall set of categories of consultation competence. Only two respondents (3%) expressed any disapproval of individual categories. Thirty five of the 39 suggested components of consultation competence were supported by more than 80% of respondents. There was minimal support for excluding any categories or components of consultation competence, for moving any components to different categories or for the inclusion of new categories or components. Eighty eight per cent of respondents were in favour of the need to identify priorities between any agreed categories of consultation competence and 79% expressed approval of the suggested weightings. Although 42% of respondents indicated a wish for some alteration in weightings, the mean values for all consultation categories suggested by all respondents were almost identical to the original weightings in the Leicester package. CONCLUSION: The face validity of the categories and components of consultation competence contained in the Leicester assessment package has been established, and the suggested weightings of consultation categories have been validated. Consequently, the criteria contained in the Leicester package can be adopted with confidence as measures against which performance can be judged in formative or summative assessment of consultation performance in general practice.
Assuntos
Competência Clínica , Medicina de Família e Comunidade/normas , Comunicação , Humanos , Distribuição Aleatória , Encaminhamento e Consulta , Reprodutibilidade dos Testes , EscóciaRESUMO
Though many general practitioners (GPs) now take part in audit, there is still concern about the extent to which participation in audit leads to improvements in practice. Improved methods are needed for the incorporation of research evidence into criteria for use in audit. In this paper, a six-stage systematic method is described for developing audit protocols containing prioritized evidence-based criteria. The stages are: selection of a topic, identification of key elements of care, focused literature reviews, prioritization of the criteria on the strength of the evidence and impact on outcome, preparation of full documentation, and peer review.
Assuntos
Medicina Baseada em Evidências , Medicina de Família e Comunidade/normas , Auditoria Médica/métodos , Protocolos Clínicos , Prioridades em Saúde , Humanos , Revisão por Pares , Reino UnidoRESUMO
It is the responsibility of practicing physicians to determine, at the earliest possible time, the presence or absence of neoplastic disease of the cervix. Modes of treatment for cervical cancer will vary according to geographic location, the expertise of those providing treatment, and current clinical trials.
Assuntos
Neoplasias do Colo do Útero/diagnóstico , Biópsia , Carcinoma in Situ/cirurgia , Continuidade da Assistência ao Paciente , Feminino , Humanos , Histerectomia , Iodo , Metástase Linfática , Metástase Neoplásica , Radioterapia , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/cirurgia , Esfregaço VaginalRESUMO
Review criteria are designed to enable clinicians and others to assess care. However, there is no established method for developing criteria, and they are often confused with guidelines. Criteria should comprise measurable activities that are appropriate for the setting in which they are to be used. They should also be based on research evidence and prioritised according to the strength of that evidence and effect on outcome. Good criteria can be used to aid implementation of guidelines by providing a standard against which to monitor performance and enabling clinical audit.
Assuntos
Pesquisa sobre Serviços de Saúde , Guias de Prática Clínica como Assunto , Garantia da Qualidade dos Cuidados de Saúde , Tomada de Decisões , Prioridades em Saúde , Humanos , Auditoria Médica , Qualidade da Assistência à Saúde , Reino UnidoRESUMO
OBJECTIVE: To encourage active participation of Leicestershire general practitioners and their staff in audit; to examine the use of vitamin B-12 injections and to achieve a more appropriate use. DESIGN: Implementation of an agreed audit protocol, with central analysis and feedback of anonymous and aggregated data by a medical audit advisory group. SETTING: All 147 Leicestershire practices. MAIN OUTCOME MEASURES: Participation in the complete audit cycle, comparison of actual use of vitamin B-12 injections with agreed criteria of use, and assessment of improvement in use. RESULTS: 264 general practitioners (55% of all doctors from 49% of all Leicestershire practices) completed both phases of the audit cycle, and 321 (67%) completed phase 1 only. Twenty four (16%) practices failed to participate from the outset, and a further 58 (35%) dropped out at various stages. Only 10 of the 37 singlehanded practices completed the audit, although 34 initially agreed to participate. If singlehanded practices were excluded, 56% (61) of practices completed both phases of the audit cycle. In total 1714 patients received B-12 injections. Appropriate use increased from 62% in phase 1 to 72% in phase 2 of the audit; there was a 32% reduction in the number of patients inappropriately receiving B-12 (521 to 352), and the proportion of patients receiving B-12 at the correct frequency rose from 58% to 72%. The proportion of patients in whom all the diagnostic criteria for pernicious anaemia were established before treatment with B-12 was 27% in phase 1 and 28% in phase 2. CONCLUSION: Our study suggests that single topic audits organised by a medical audit advisory group can encourage large numbers of general practitioners to participate and can bring about changes in behaviour resulting in improvements in standards of care. Nevertheless, advisory groups will need to devise strategies to encourage even higher levels of involvement, most particularly from singlehanded practices.