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121.
Clinical characteristics of rapidly progressive leuko-araiosis 总被引:1,自引:0,他引:1
S. Tarvonen-Schröder I. Räihä T. Kurki T. Rajala L. Sourander 《Acta neurologica Scandinavica》1995,91(5):399-404
Introduction – 38 patients found to have either pure leuko-araiosis (LA) or LA combined with infarction(s) on computer tomography (CT) in 1989 were re-examined in 1992 in order to evaluate the progression of LA. The follow-up period averaged 3.2 years. Material and methods - The clinical and radiological data on patients in 1989 were collected from hospital records and re-evaluated. The patients were re-examined clinically (including 24 hour ambulatory blood pressure measurement), and neuroradiologically (CT) in 1992 for this study. Results – 11 (29%) patients were found to have significant (rapid) progression of the extent of LA on CT during the follow-up. At baseline, there was no significant difference in the mean number of brain infarctions between the groups with progressing (prLA) and non-progressing LA (nprLA) or between the number of cortical and central infarctions within these groups. At follow-up, the total number of infarctions had increased significantly in both groups, but it was mostly because of the increase in cortical infarctions in the prLA group (p = 0.043) and, conversely, the central ones in the nprLA group (p = 0.011). prLA was found to be related to heart failure (82% vs 37%, p = 0.029) and atrial fibrillation (55% vs 19%, p = 0.047), whereas nprLA was strongly associated with a sudden onset of symptoms (78% vs prLA 18%, p = 0.001) like a-true brain infarction. Other clinical factors, including mean blood pressure and heart rate, did not clearly differentiate between the groups. Conclusion - The results suggest that there are different subgroups of patients with LA associated with various vascular factors. The occurrence of LA is not related to the distribution of infarctions. The progression of LA is not related to the number of brain infarctions or to the simultaneous increase of infarctions on CT. 相似文献
122.
《Journal of molecular neuroscience : MN》1996,29(1):67-78
We studied the activity and kinetic parameters of synaptosomal Na, K-ATPase during 15 min of forebrain ischemia and following
60 min of reperfusion produced by reversible common carotid occlusion in Mongolian gerbils. A synaptosomal fraction was obtained
by both differential centrifugation of brain tissue homogenate and centrifugation of crude mitochondrial fraction at a discontinual
sucrose density gradient. We found two components of ATP concentration dependence of ATP hydrolysis that represent two types
of ATP-binding sites: high affinity and low affinity. Neither ischemia nor reperfusion affected kinetic parameters of a high-affinity
site. However, lowaffinity site parameters were affected by both ischemia and ischemia followed by reperfusion. Maximal velocity
(V
max) decreased by 43 and 42% after ischemia and after ischemia/reperfusion, respectively. The apparentK
m for ATP decreased by 52% after ischemia and by 47% after ischemia/reperfusion. The apparent affinities for K+ and Na+ were determined from the ATP hydrolysis rate as a function of Na+ and K+ concentrations. We found the half-maximal activation constant for K+ (K
a
K+) increased by 60% after ischemia and by 146% after ischemia/reperfusion. On the other hand, we found thatK
aNa+ decreased significantly after ischemia/reperfusion (16%). We concluded that it is the dephosphorylation step of the ATPase
reation cycle that is primarily affected by both ischemia and ischemia/reperfusion. This might be caused by alteration of
the protein molecule and/or its surroundings subsequent to ischemia. 相似文献
123.
L. LEIBOVICI W. R. GRANSDEN S. J. EYKYN H. KONSIBERGER M. DRUCKER S. D. PITLIK I. PHILLIPS 《Journal of internal medicine》1993,234(1):83-89
Abstract. Objectives. To define risk factors associated with bacteraemia caused by Staphylococcus aureus or coagulase-negative staphylococci; and to use them to define patients in need of empiric anti-staphylococcal antibiotic treatment. Design, Derivation set: observational, prospective study; validation set: retrospective analysis of a prospectively collected database. Setting. Derivation set: Beilinson Medical Centre, Petah Tiqva, Israel—a 900-bed university hospital. Validation set: St Thomas's Hospital, London, UK—an 800-bed teaching hospital. Subjects. All episodes of bacteraemia detected at Beilinson Medical Centre between March 1988 and September 1990 (derivation set, n = 1410), and at St Thomas's Hospital during 1987–1990 (validation set, n = 1040). Interventions. None. Main outcome measures. Percentage of staphylococcal bacteraemia in groups of patients defined by the models. Results. The following factors were associated with Staphylococcus aureus bacteraemia: focus of infection (whether high or low risk), haemodialysis, intravenous drug abuse and infection acquired in the orthopaedic ward. A logistic model was used to divide the derivation set into three groups with percentages of Staphylococcus aureus bacteraemia of 1.8%, 13.2% and 33.7% (P < 0.0001); and the validation group 2.5%, 18.2% and 53.2% (P < 0.0001). Factors associated with coagulase-negative staphylococcal bacteraemia were: central or peripheral intravenous catheter as the focus of infection, a preterm neonate, the presence of a central intravenous catheter, low temperature, and a low white blood cell count. A second model including those factors was used to divide the derivation set into three groups with percentages of coagulase-negative staphylococcal bacteraemia of 1.9%, 22.8%, and 43% (P < 0.0001). In the validation set, the percentages were 2.9%, 22.4% and 31.0% (P < 0.001). Conclusions. The present study defines groups at high risk for staphylococcal bloodstream infection, in which empiric treatment should include an anti-staphylococcal drug. 相似文献
124.
住院医师临床技能评估方法探讨 总被引:5,自引:0,他引:5
该文总结了安徽省立医院住院医师培训情况,提出了必须引入实践性考核作为住院医师临床技能考核的主要方式。根据临床技能评价的项目,制定了内科、外科、影像科住院医师临床技能评估指标体系,确立了临床技能考核的原则,并组织实施。这种评估方法能全面考核住院医师的临床技能,但在新的医疗形势下,需建立相关配套措施来保证实施。 相似文献
125.
P. CURZEN 《Medical education》1987,21(6):498-504
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. 相似文献
126.
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。 相似文献
127.
A. N. THOMSON 《Medical education》1992,26(5):364-367
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. 相似文献
128.
FRESH FROZEN PLASMA: IS IT FAREWELL? 总被引:1,自引:0,他引:1
JOHN CASH 《Vox sanguinis》1994,67(S3):121-124
129.
磁共振水成像的临床应用及其进展 总被引:4,自引:0,他引:4
磁共振水成像是近年来磁共振成像研究的重大进展之一。具有无创,无辐射的特点,它利用重T2加权成像使含水器官显影,应用于胰胆管,泌尿系,椎管,涎管,内耳迷路,输卵管等含水器官的显示,具有良好的应用前景。 相似文献
130.
人工心脏瓣膜感染性心内膜炎临床分析 总被引:1,自引:0,他引:1
目的 探讨人工心脏瓣膜感染性心内膜炎 (PVE)的临床特征 ,提高PVE的诊治水平。方法 通过分析 2 6例PVE的临床表现 ,分析其治疗和预后情况。结果 PVE临床不少见 ,发热是最常见的临床表现 ( 92 .3 % ) ,其次是贫血 ( 88.5% ) ,栓塞 ( 2 6.9% )。血培养和超声心动图是诊断PVE的重要手段 ,阳性率分别为 46.2 %和 73 .1%。早期PVE较晚期PVE预后差、死亡率高 ,分别为 66.7%、3 3 .3 %。主张早期、大剂量、长疗程的抗生素治疗 ,早期手术治疗可改善预后。本组病人总死亡率 3 4 .7% ,死亡原因 :心力衰竭 ( 77.8% )、栓塞 ( 2 2 .2 % )。结论 PVE预后差、死亡率高 ,应早期预防、早期诊断、早期治疗 相似文献