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191.
Five cases of chronic paroxysmal atrio-ventricular block are reported, being unusual in the siting of the conduction defect within the trunk of the bundle of His, and in the "paradoxical" mode of onset of the block. The ventriculograms which were carried out, and the escapes, were of normal duration in four cases and the intracavitary recordings showed a double His potential in all patients. In one case, the block during phase 4 seemed to occur at the height of the trunkal Wenkebach periods, and in another it could be brought on by manipulation of the vagus. In all five cases, a favorable conduction zone could be calculated, the block to the P waves in phase 4 occuring in an arithmetical fashion after a critical lengthening of the PR interval. The return to sinus rhythm was always related to an escape (or to an electrically induced ventricular complex), but the explanation of the initial capture on electrophysiological grounds is obscure.  相似文献   
192.
In a patient with spells of paroxysmal supraventricular tachycardia of two types, the stimulation tests demonstrated a dual intranodal conduction responsible sometimes for "usual" reciprocal rhythms (slow anterograde pathway and rapid retrograde pathway), sometimes for "reversed" reciprocal rhythms (rapid anterograde pathway and slow retrograde pathway). The latter contrasted with the lack of discontinuity of the retrograde nodal function curve (V1-V2 versus A1-A2).  相似文献   
193.
BACKGROUND: A proposed standard for the multidisciplinary assessment (MDA) of children with autism has been recently published by the National Autistic Society. This prompted a review of current practice at the child development centre in our local centre, to judge whether we were able to conform to the proposed national standard. The recommendation is that a child should complete a three-stage assessment process from referral to completion of assessment within 30 weeks, with set times for completion of each stage (6, 7 and 17 weeks respectively). We applied this assessment model to children with a range of neurodevelopment problems, as the process of MDA is the same, irrespective of diagnosis. METHODS: A retrospective analysis of medical and therapy records of all MDAs was carried out between April 2001 and March 2002. RESULTS: In the 12-month period studied, 52 MDAs were performed. Delays occurred, as judged by the standard, at all three stages of the assessment process. A total of 42% of children were seen within 6 weeks of initial referral, 37% within a further 7 weeks for specialist assessment, and 37% within a further 17 weeks for completion of MDA. As delays occurred at all stages, the cumulative total showed that only 19% of children completed all three stages within the recommended 30-week standard. Barriers encountered included waiting times to see professionals, parental non-attendance and prolonged assessment of complex problems. Some of these factors are outside our control, and on removing these factors the data were re-analysed. This resulted in a slight improvement to 45%, 48% and 49% for completion of stages 1, 2 and 3 respectively. The major reason for delay remained the service capacity. CONCLUSION: In our experience the standards proposed by the National Autistic Society are not practical within present resources. We suggest that a reasonable expectation is to complete all assessments, from first concern to completed MDA, should be carried out within 52 weeks with present levels of resources. Any further improvement will require additional resources to reduce waiting times and increase the capacity.  相似文献   
194.
Chest wall mesenchymoma is a rare tumour in childhood and often presents in the neonatal period. In the past all patients have received surgical treatment with quite a high morbidity. We present here three further cases that presented in infancy, two of which received minimal therapy with good results in each case. We would propose from these cases that once the diagnosis has been established by biopsy that total surgical resection not be carried out unless cardiac or respiratory embarrassment is present.  相似文献   
195.
Culture forms of 104 stocks of Trypanosoma cruzi isolated in different regions of the State of Bahia were compared by electrophoresis of six enzymes. The three distinct combinations of isoenzyme patterns seen were designated Z1, Z2 and Z3. In an area of endemic Chagas's disease in eastern Bahia, T. cruzi Z1 was associated with sylvatic mammals and sylvatic triatomines, whereas T. cruzi Z2 was associated with a separate domestic cycle of transmission. T. cruzi Z1 was also found in sylvatic triatomines from other parts of the State. In contrast, in an area of the São Francisco Valley region of western Bahia, both T. cruzi Z1 and Z2 were isolated from man, domestic animals, and peridomestic rats. T. cruzi Z3 was isolated from an armadillo and from Panstrongylus geniculatus, a triatomine commonly found in armadillo burrows.Both T. cruzi Z1 and Z2 appeared to be pathogenic in man: T. cruzi Z1 was isolated from patients with acute Chagas's disease and from a single patient with chronic cardiac manifestations. T. cruzi Z2 was isolated from some asymptomatic individuals but was also associated with acute disease and chronic cardiac and digestive syndromes.  相似文献   
196.
Eight research laboratories in Europe and the United States of America were selected on the basis of having published data on Schistosoma mansoni and S. japonicum antigens to participate in a study of various antigen/test combinations for immunodiagnosis of schistosomiasis. The serum bank consisted of 395 well documented sera from four endemic areas in Brazil (2 areas), Kenya, and the Philippines. Altogether, 21 S. mansoni and four S. japonicum antigen and immunoassay combinations were evaluated.  相似文献   
197.
The radiation technique described is an unconventional method of treatment for carcinoma cervix patients and is essentially external beam therapy alone, using a 60Cobalt rotation plan. This is in contrast to the more conventional series of 2 or 3 intracavitary radium insertions, either preceded and/or followed by fixed field external beam therapy. An advantage to the patient from this treatment scheme is the avoidance of the trauma associated with the repeated anaesthetics required for uterine and vaginal radium applications. Dosage levels have also been determined to ensure minimal post-radiation complications, and the 5- and 10-year survival rates for stage II and stage III cases are comparable with the survival results published by other centres. The series was treated during 1957-64 and consisted of all stage II and III cases referred to the Westminster Radiotherapy Department during this period, together with 13 stage I cases which were considered to be poor anaesthetic risks, and 4 stage IV cases. The 5- and 10-year survival rates for 69 stage II cases were 44% and 36% respectively, and for 81 stage III cases were 38% and 23% respectively.  相似文献   
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D J Mott 《Medical physics》1984,11(5):666-669
On the EMI 7070 CT scanner the data contained in the wedge files has been averaged resulting in a 6% reduction in the noise content of images. This noise reduction can either be used to improve image quality or can be offset by reducing the x-ray tube current by 12%. The averaging method will be outlined and its rationale discussed.  相似文献   
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