Influence of pre-target cortical potentials on saccadic reaction times

 Saccades elicited by suddenly appearing targets show a broad distribution of reaction times. This may depend on variations in the subject’s state of preparation before target onset. To test this hypothesis, we recorded scalp event-related potentials from eight human subjects to investigate whether differences in saccadic reaction times (SRTs) are related to differences in cortical slow potentials prior to target onset. Compared with trials with medium SRTs (180–230 ms), trials with fast SRTs (130–180 ms) were found to be preceded by a more negative slow potential and trials with slow SRTs (230–280 ms) were found to be preceded by a more positive slow potential. These results support the hypothesis that cortical activation prior to target appearance influences SRTs. Received: 21 June 1996 / Accepted: 15 January 1997     

A follow-up study of respiratory function in workers exposed to acid aerosols in a food-processing industry

A follow-up investigation was performed on 49 female workers studied 2 years earlier in a vegetable-pickling plant. Acute and chronic respiratory symptoms and ventilatory capacity measurements were recorded during the original and the follow-up studies. Maximal expiratory flow-volume (MEFV) curves were recorded during the Monday morning work shift. The forced vital capacity (FVC), 1-s forced expiratory volume (FEV1), and flow rates at 50% and the last 25% of the FVC (FEF50, FEF25) were measured. There were small increases in the prevalence of chronic symptoms between the two studies for both smokers and nonsmokers, but these did not reach statistical significance. Five workers at the time of the initial study had a diagnosis of occupational asthma; only one of these was still working at the time of follow-up. Workers lost to the follow-up had lower lung function than those seen at follow-up. In workers who were followed, larger than expected mean annual declines were noted for all ventilatory capacity parameters in both smokers (FVC 0.070 l, FEV1 0.070 l; FEF50 0.355 l/s, FEF25 0.270 l/s) and nonsmokers (FVC 0.045 l, FEV1 0.045 l, FEF50 0.285 l/s; FEF25 0.130 l/s). The decrease was particularly pronounced for FEF50 and FEF25. The accelerated decline in ventilatory capacity tests noted in the female nonsmokers suggests an independent effect on lung function of work exposure in this environment. Our data confirm that work in the pickling industry, particularly in small, poorly regulated plants, has deleterious effects on respiratory function. Received: 24 September 1996 / Accepted: 19 June 1997     

Three antidepressants (amitriptyline,dothiepin, fluoxetine), with and without alcohol,compared with placebo on tests of psychomotor ability related to car driving

Eight female volunteers received acute doses of amitriptyline 50 mg (AMI), dothiepin 50 mg (DOT), fluoxetine 40 mg (FLU) or placebo both with and without a ‘social’ dose of alcohol (ALC) equivalent to 0·5 g/kg body weight absolute alcohol. Performance on a variety of tests of psychomotor ability and cognitive function (critical flicker fusion, choice reaction time, tracking, Maddox Wing and simulated car steering) were performed at 1·5 and 4 hours following treatment. AMI and DOT both with and without ALC impaired performance on a range of tests at either or both 1·5 and 4 hours, although the effects of AMI and AMI + ALC were more widespread and severe than those found with either DOT or DOT + ALC. FLU and FLU + ALC showed no evidence of impairment on any test at either the 1·5 or the 4 hours assessments. The results suggest that there are differences between the experimental substances, at the doses used, in their intrinsic potential for impairing aspects of psychomotor performance and cognitive function.     

Students'' assessment of a course in obstetrics and gynaecology

A complete annual entry of 181 students were administered a questionnaire in which they were invited to make value judgements about all aspects of their 3-month course in obstetrics and gynaecology. The resulting performance indicators were used to compare individual staff and clinical firms.     

江西省528例非何杰金氏恶性淋巴瘤回顾性病理分析

本文收集了我省十年(1974—1983)来诊断为恶性淋巴瘤的病例,按免疫功能分类复查了全部切片,最后确诊为非何杰金氏恶性淋巴瘤(NHL)528例,进行了分析。本组NHL在首发部位、类型分布等方面与国内外有所不同。本组NHL首发于淋巴结外的占64.02％,明显高于国内其它省、市,而滤泡型淋巴瘤则低于国内多数地区。T细胞淋巴瘤占14.84％,较国内、外均低。并提出提高制片质量和广泛开展及应用免疫学技术的重要性。     

Can communication skills be assessed independently of their context?

In many examinations, communication skills tend to be treated as if they are a single attribute independent of the context of the communication. However, it is clear that such assessments are confounded by candidates' knowledge or lack of knowledge of the medical issues about which they are communicating. In the 1990 Part One examination for Membership of the Royal New Zealand College of General Practitioners candidates were provided with all the essential knowledge relevant to the problem they were to communicate about. Despite this, performance was still seen to be context specific, demonstrating that such specificity is not purely knowledge related. Candidates completing the examination were observed to share information about the cases with candidates about to commerce. There was no evidence that performance was enhanced by such breaches in examination security.     

How do clinicians learn to request permission for autopsies?

A postal survey of 434 clinicians at four local hospitals was undertaken in order to identify the methods by which clinicians learn how to request permission for hospital autopsies and to assess the preferred techniques and timing of relevant communication skills training. The majority of 128 responding clinicians had learnt through personal experience with some assistance from senior colleagues and peers. Few clinicians appeared to have learnt through formal training. The preferred methods for the provision of communication skills training were training in small groups (such as seminars or tutorials) and observation of clinicians at work. The most desirable time for the provision of this training was considered to be between the beginning of the final undergraduate year and the end of the pre-registration house officer year. The communication skills training provided within medical education is in need of improvement. More emphasis should be given to clinical-task- or situation-specific applications such as requesting permission for autopsies.     

The impact of lower urinary tract symptoms on general health status and on the use of prostatectomy

Our objective was to determine the extent to which lower urinary tract symptoms affect the general health status of men and contribute to the decision to undergo surgery. A cross-sectional population survey using postal questionnaires was conducted in the North West Thames health region, followed by a prospective cohort study of men undergoing prostatectomy (North West Thames and Oxford regions). The subjects in the first survey were 221 men aged 55 and over with previously reported mild, moderate or severe urinary symptoms; subjects in the second study were 388 men undergoing prostatectomy. Main outcome measures were selfreported symptom severity, bothersomeness and general health status (Nottingham Health Profilie, Part 1). The response rate among eligible responders in the population survey was 85.7%. Increasing symptom severity was associated with worsening NHP scores for energy, emotional reactions, sleep and physical mobility (p<0.01). Increasing bother-someness of symptoms was associated with emotional reactions, sleep and pain (p<0.05). Men undergoing surgery reported worse health status than men in the population with the same severity of symptoms as regards emotional reactions, energy and pain. For a given level of symptom severity, the impact of those symptoms on aspects of a man's general health status may be the determinant of seeking and undergoing surgery. Greater understanding of the factors that affect a man's response to his symptoms is needed in interpreting the decision to seek and accept treatment.     

骨盆骨折槽型固定器的研制及临床应用——附62例临床分析

为解决骨盆不稳定性骨折固定难，易产生并发症的难题，结合骨盆的特征进行研究，设计出一种新型骨盆骨折固定器，经62例骨盆不稳定性骨折的治疗观察，随访6个月～2年零6个月，治疗前后X线检查及临床疗效评定：治愈50例，好转12例，认为该固定器设计合理，操作简便，固定牢靠，有加压、撑开、纠正旋转等多项功能结合干一体，仅通过四枚4mm螺纹针，穿入髂骨的髂前上棘处，是一种治疗骨盆不稳定性骨折比较新颖和理想的外固定器。     

Foreign body aspiration in children. The diagnostic value of signs,symptoms and pre-operative examination

One hundred and fifteen patients, between 6 months and 12 years of age, had bronchoscopy on suspicion of foreign body aspiration. The histories of these patients were studied to examine the diagnostic value of signs, symptoms and examinations, and to determine the time that passed between aspiration and removal of the foreign body. The sensitivity of the symptoms choking and coughing was fairly high (81 and 78%), but the specificity was poor. The sensitivity of a chest radiograph was 82%, the specificity 44%. The sensitivity of radiographs on inspiration and expiration was 80%, the specificity 55%. The patients had been referred with the initial diagnosis foreign body aspiration (80), pneumonia (34), or subglottic laryngitis (1). In 85 patients a foreign body was identified and extracted. The other 30 patients had respiratory tract infections. The initial diagnosis of foreign body aspiration was correct in 61 out of 85 patients. In these cases, the period between aspiration and extraction of the foreign body was a mean 6 days, compared with 55 days, if the initial diagnosis was pneumonia or sub-glottic laryngitis. We conclude that the diagnosis of foreign body aspiration is too often missed, and that, apart from bronchoscopy, diagnostic tools are of little value.