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991.
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The possibility of nuclear war may be the most significant threat to health in the world. Medical practitioners have played, and should continue to play, a leading role in raising awareness of this danger. In the present study, the attitudes that predict a specific antinuclear-war behaviour (that is, signing a letter to the Prime Minister of Australia to request more active political effort to prevent nuclear war) were studied in a group of 143 undergraduate medical students. Attitudes towards that particular behaviour were assessed by means of a questionnaire, and the differences in attitude between students who chose to sign and those who chose not to sign the letter were analysed statistically by means of discriminant analysis. The key differences in attitude between signers and non-signers of the letter was in their belief that such an action would achieve tangible positive outcomes. The results are discussed in terms of the need to target strategies of change for the specific attitudes which are likely to modify behaviour and to promote antinuclear behaviours in medical practitioners, which in turn may alter the behaviour of politicians.  相似文献   
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Electroretinograms in autism: a pilot study of b-wave amplitudes   总被引:2,自引:0,他引:2  
The authors recorded electroretinograms for 27 autistic patients and 20 age- and sex-matched healthy volunteers. Thirteen (48%) of the autistic patients demonstrated subnormal b-wave amplitudes, which may indicate abnormal retinal function. One patient was tested serially at two sites; his low b-wave amplitude did not vary over time or between the two sites. If this retinal finding can be confirmed at other laboratories and in larger samples of autistic patients, it might provide a marker for a specific subtype of autism.  相似文献   
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We previously reported that some Hodgkin's disease patients had elevated hprt mutant frequencies in peripheral blood lymphocytes long after cessation of therapy. To determine if these elevations in mutant frequency represent true persistently elevated mutation frequencies, we recruited for a prospective study six previously treated Hodgkin's disease patients and five patients who had been treated for squamous cell carcinoma of the head and neck. These individuals were studied several times over a 6-7-month period. The results confirmed that a subset of patients have persistently high mutant frequencies when compared to 71 previously studied controls. The present study was designed to determine if the elevated mutant frequencies of treated patients represented independent mutations or resulted from the in vivo expansion of single mutant cells. We used the polymerase chain reaction to examine DNA single-strand conformation polymorphisms at the T-cell receptor gamma locus of individual mutant clones. This analysis showed that at any given time 20.1% of the mutants from Hodgkin's disease patients and 17.5% of the mutants from squamous cell carcinoma patients consisted of siblings, identified as having identical polymerase chain reaction/single-stranded conformation polymorphism patterns. The remaining mutants had unique polymerase chain reaction/single-stranded conformation polymorphism patterns and therefore can be presumed to have arisen from independent mutational events. Particular sibling mutants generally did not persist over time. However, one patient had one mutant clone which persisted but slowly decreased in prevalence over a 7-month sampling period. The data demonstrate that treatments for cancer result in persistently elevated mutation frequencies at the hprt locus in some, but not all, patients.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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In order to better define management policies we attempted to construct risk models for rebleeding on initial conservative management and mortality after emergency surgery for failure of medical therapy in 387 patients with bleeding gastric ulcer. Several different models were constructed using logistic regression analysis with validation by the 'leaving-one-out' method. However, despite large patient numbers, modelling in this way is difficult because of inherent wide variation between patients. Suitable models for rebleeding were regarded as rather unsatisfactory, for although overall accuracy was 86%, sensitivity was only 54%. More promising was a model for mortality after emergency surgery which had an accuracy of 93% and a sensitivity of 80%. Such mortality models incorporating age, history of previous malignant disease or dyspepsia, the presence or absence of ascites and total transfusion requirements may well prove to be of value in surgical practice. This paper seeks to examine the process of modelling rebleeding and mortality and of interpreting the models produced.  相似文献   
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