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21.
Uninjected postmortem normal lung from 49 children aged 1 hour to 14 years was studied using quantitative morphometric techniques to assess arterial size, number and muscularity, particularly in the respiratory region of lung. Arterial size increased most rapidly during the first 2 months of life, but growth rate remained high during the first 4 years. At all ages, the range of values for the mean external diameter of arteries accompanying peripheral airways was considerable, but marked differences from the normal range were usually associated with a marked difference in stature. Arterial number increased rapidly in the first 2 months, but subsequently arteries multiplied at the same rate as alveoli, and the alveolar:arterial ratio was relatively constant. Mean percentage arterial medial thickness fell quickly during the first 10 days and continued to decrease during the first 3 months of life, after which there was little change. The intra-acinar arteries became more muscular during childhood as they increased in size. Vein muscle wall thickness was low throughout childhood. The normal values given in this paper provide a basis for the evaluation of lung biopsies in childhood.  相似文献   
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Superior vena cava syndrome developed in a patient in whom an endocardial transvenous pacemaker had been inserted five years previously. Venography demonstrated an obstructing lesion at the junction of the superior vena cava and right atrium. Balloon catheter dilatation failed to afford any relief from her progressive symptoms. Exploration of the area revealed a benign fibrotic lesion encircling the pacemaker lead within the right atrium. Excision of the lesion, removal of the lead, and patching the right atrium with pericardium resulted in rapid cure.  相似文献   
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To study the effects of sampling through cardiac catheters on indices of platelet function, we measured the levels of platelet factor 4 (PF4), beta thromboglobulin (BTG), and platelet aggregate ratio (PAR) in 10 patients with atrioventricular accessory pathway (AVNAP), six patients with primary pulmonary hypertension (PPH), and six patients with critical narrowing of the left anterior descending artery (LAD). In AVNAP and LAD patients samples were drawn simultaneously from a peripheral vein, coronary sinus, and brachial artery; in AVNAP patients samples were also obtained from the axillary vein before the coronary sinus was entered. In PPH patients samples were drawn from pulmonary artery, aorta, and a peripheral vein; in these patients the effects of an intravenous infusion of prostacyclin (PGl2) (2 to 8 ng/kg/min) on PF4, BTG, and PAR were also studied at all sampling sites. In all patients arterial, coronary sinus, pulmonary arterial, and axillary venous levels of PF4, BTG, and PAR significantly exceeded those measured in the peripheral vein. PGl2 infusion resulted in a significant decrease of PF4 at all sampling sites, while no consistent BTG changes were observed and PAR levels did not decrease in the peripheral vein. Although a considerable interpatient variability in PF4 levels was observed, a significant (r = 0.91) correlation was found in patients with AVNAP between simultaneous coronary sinus and arterial PF4 levels. The value of PF4 coronary sinus-arterial difference in LAD patients was consistently higher than that calculated in AVNAP patients (54.5 ± 28.9 vs 4.2 ± 3.8 ng/ml). In conclusion: (1) a considerable and variable degree of platelet activation occurs with catheter sampling, preventing the measurement of absolute levels of platelet metabolites; (2) among the indices examined PF4 appears the most sensitive for detecting changes in platelet activity; and (3) the measurement of coronary sinus-arterial PF4 differences may provide information on directional changes in transcardiac platelet behavior.  相似文献   
24.
In 12 patients with left ventricular aneurysm and chronic congestive heart failure, left ventricular functional reserve was assessed from the hemodynamic response to exercise stress after administration of isosorbide dinitrate. Two to 23 months (mean 8.6 months) after left ventricular aneurysmectomy hemodynamic measurements were made with the patient at rest and during exercise and were analyzed with respect to preoperative data. Left ventricular aneurysmectomy reduced mean left ventricular filling pressure from 25 to 17 mm Hg at rest (p < 0.02) and from 39 to 32 mm Hg during exercise (p < 0.05). There was no significant change in mean stroke volume index at rest or during exercise.Changes in resting and exercise hemodynamic indexes of left ventricular function produced by aneurysmectomy were inversely related to preoperative left ventricular function. Hence, hemodynamic status was less likely to improve In patients with good preoperative left ventricular function. Similarly, resting and exercise values for left ventricular function tended to improve in patients with reduced ejection fraction of the contractile section of the left ventricle. Left ventricular aneurysmectomy was generally effective in reducing left ventricular filling pressure but failed to achieve clinically important improvement in left ventricular performance during exercise. In patients with chronic congestive heart failure, left Ventricular aneurysmectomy should be performed only after careful assessment of preoperative left ventricular functional reserve.  相似文献   
25.
Introduction. Behavioral and cognitive improvements in clients with Asperger's Syndrome (AS), employing continuous performance tests (CPTs), intelligence and academic measures, and electroencephalographic data, have been reported following 40 sessions of neurofeedback (NFB) training combined with coaching in metacognitive strategies. However, measures of executive functions (EFs) in this population have not been commonly employed and NFB is still not commonly used as a treatment for AS. Therefore, this pilot project used Tower of London – Drexel University (ToLDX), an individually administered test of EFs, in addition to the previously mentioned measures. The goal of the current study was to investigate the utility of ToLDX as an assessment tool for clients with AS as well as further study the effects of NFB and training in metacognitive strategies on executive functioning in clients with AS.

Method. Nineteen consecutive clients at the ADD Centre, Toronto, Canada (M age = 12 years 0 months) recruited over a 2½-year period all had full clinical assessment, completed age appropriate questionnaires, and were tested pre- and post-40 NFB sessions.

Results. Following the training, clients with AS were able to plan more efficiently, inhibit premature responses, and shift set with greater ease, as well as solve problems more quickly as measured by their ToLDX scores. On CPTs, clients with AS showed a trend toward less impulsivity. Finally, improvement in their scores on ToLDX was not affected by age or IQ.

Conclusion. These data are important because they provide an extension of results of previous studies (Reid, 2005), demonstrate the utility of tests of executive functions in a clinical setting with clients with AS, and suggest directions for further controlled research in this area.  相似文献   
26.
The European Cytogeneticists Association Register of Unbalanced Chromosome Aberrations (ECARUCA, www.ecaruca.net) is an online database initiated in 2003 that collects and provides detailed, curated clinical and molecular information on rare unbalanced chromosome aberrations. ECARUCA now contains over 4800 cases with a total of more than 6600 genetic aberrations and has over 3000 account holders worldwide. Recently, the ECARUCA web site was renewed, including the presentation of interesting case reports in collaboration with the European Journal of Medical Genetics. This article gives an overview of the current status and future plans of the online ECARUCA database.  相似文献   
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《Revue neurologique》2022,178(4):291-297
We have reviewed seminal interactions between British and French physicians prior to and following the establishment of the Paris and London Schools of Neurology from the mid-19th to the early 20th centuries. Our first article focused on British and French physicians, places and events. In this second part of our review we have examined the interactions between British and French Neurological Societies and Journals, including: (1) The Neurological Society of London founded in 1886, which became the Section of Neurology of the Royal Society of Medicine; (2) The Société de Neurologie de Paris founded in 1899, later renamed as The Société Française de Neurologie; (3) The journal Brain and its precursors and successors; (4) The journal Revue Neurologique and its precursors. We illustrate the constructive influence of Anglo-French interactions on the early development of neurology by the distinguished physicians who were corresponding members respectively of the British and French Neurological Societies and the scientific articles published by French authors in Brain and by British scientists in Nouvelle Iconographie de la Salpêtrière, Archives de Neurologie and Revue Neurologique.  相似文献   
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