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51.
MJ Carvalho AH van den Meiracker F Boomsma AJ Man in 't Veld J Freitas O Costa AF de Freitas 《Canadian Metallurgical Quarterly》1997,62(1-2):63-71
Disabling orthostatic hypotension, due to insufficiency of the autonomic nervous system, is a common complication of type I familial amyloidotic polyneuropathy (FAP). We investigated whether oral treatment with L-threo-3,4-dihydroxyphenylserine (L-threo-Dops), a noradrenaline precursor, might be of therapeutical benefit. In twenty untreated FAP patients, aged 33 to 44 years, who, because of severe orthostatic hypotension, were bedridden or constrained to a sitting life, supine and erect blood pressure (BP), plasma noradrenaline and tilting time, defined as the interval (s) between the beginning of a 60 degrees head-up tilt and the occurrence of orthostatic symptoms (dizziness, blurred vision or near syncope) were determined before and at repeated intervals during oral treatment with L-threo-Dops, 100 mg bid, for 6 months. Before treatment supine mean BP was 80 (76-85) mmHg (mean and 95% CI), supine plasma noradrenaline was low, 59 (41-77) pg/ml and tilting time ranged from 38 to 118 s. In response to tilt, mean BP immediately fell by 36 (31-41) mmHg, whereas plasma noradrenaline increased by only 11 (0-21) pg/ml (p = 0.05). After 3 to 5 days of treatment with L-threo-Dops all patients experienced marked improvement of their orthostatic tolerance as reflected by their ability to walk freely around. This effect sustained throughout the six months of treatment. Plasma noradrenaline increased moderately by 37 (11-63) pg/ml (p = 0.02) and supine mean BP increased by 8.6 (5.8-12.4) mmHg (p < 0.001) during chronic treatment. Supine or nocturnal hypertension did not develop, the fall in mean BP in response to tilt diminished by 12.5 (6.5-17.3) mmHg (p < 0.001) and tilting time became longer than 600 s in all patients. Because of its efficacy, its sustained duration of action and the lack of side effects, L-threo-Dops is advocated to improve orthostatic tolerance in patients with autonomic insufficiency due to FAP. 相似文献
52.
The hemolytic uremic syndrome (HUS) comprises hemolytic anemia, acute renal failure, and thrombocytopenia. It is the most frequent cause of acute renal failure in childhood. Ninety percent of the patients have a diarrheal prodrome, and are referred to as having typical HUS. Approximately 10% exhibit the so-called atypical HUS. Typical HUS is caused by shigatoxin-producing Escherichia coli. The toxin, bound to the globotriosyl ceramide cell receptor and internalized, interferes with protein synthesis, predominantly of endothelial cells. The main target is the kidney, but nearly every organ system can be involved. The most common extrarenal involvement is damage to the central nervous system. The central event is probably an insult to the endothelial cell with consecutive loss of antithrombogenic properties. The von Willebrand factor, activation of platelets via platelet-activating factor, other growth factors (e.g., interleukins 1, 6, 8), nitric oxide, lipopolysaccharides, activated polymorphonucleated neutrophils, and the metabolites of the arachidonic acid cascade (e.g., prostaglandin I2) are believed to be involved in the pathogenic cascade. Controlled therapeutic trials with heparin, dipyridamole, aspirin, and urokinase have not been associated with improved outcome. Antibiotics have not yielded any benefit. Plasma infusions and plasma exchange appear to be efficacious, and are justified in cases of atypical HUS and thrombotic thrombocytopenic purpura. Binding of the toxin to the intestinal lumen, and thereby inhibition of enteral reabsorption, is under investigation. 相似文献
53.
K Papasouliotis TJ Gruffydd-Jones AH Sparkes PJ Cripps 《Canadian Metallurgical Quarterly》1995,58(3):263-267
Orocaecal transit time (OCTT) was assessed in six healthy beagles by means of the breath hydrogen test (BH2T) and the sulphasalazine/sulphapyridine method (SLZ) after the administration of a test meal of canned food mixed with sulphasalazine. Orocaecal transit time was defined as the time taken from the oral administration of the test meal to the time when the first portion of the meal reached the colon. In five of the dogs the OCTTs assessed by the BH2T were shorter than those measured by the SLZ method by 30, 15, 45, 30 and 45 minutes. However, the median OCTT assessed by the BH2T (135 minutes, range 120 to 195 minutes) was not significantly different from that measured by the SLZ (180 minutes, range 150 to 210 minutes) and was highly correlated with it (r = 0.94, P = 0.016). The sixth dog maintained baseline hydrogen and plasma sulphapyridine readings throughout the monitoring period and the OCTT could not be measured. 相似文献
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The goal of orthopaedic interventions is to improve the functional health of patients, particularly physical function. The American Academy of Orthopaedic Surgeons and the Pediatric Orthopaedic Society of North America (POSNA) commissioned a work group to construct functional health outcomes scales for children and adolescents, focusing on musculoskeletal health. The work group developed scales assessing upper extremity function, transfers and mobility, physical function and sports, comfort (pain free), happiness and satisfaction, and expectations for treatment. Parent and adolescent self-report forms were developed and tested on 470 subjects aged 2-18 years. The POSNA scales demonstrated good reliability, construct validity, sensitivity to change over a 9-month period, and ability to outperform a standard instrument, the Child Health Questionnaire physical functioning scale. They were useful for a wide variety of ages and diagnoses. They appear to be ideally suited for orthopaedic surgeons to assess the functional health and efficacy of treatment of their patients at baseline and follow-up. 相似文献
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S Mushtaq IA Malik M Ahmed MS Khan AH Khan S Jamal FA Malik 《Canadian Metallurgical Quarterly》1994,44(7):169-171
Ki-1 large cell anaplastic lymphoma is a recently described variant of malignant lymphoma. A retrospective study of 10 cases of Ki-1 lymphoma was carried out at the Armed Forces Institute of Pathology (AFIP) Rawalpindi to document its clinical and morphological features. The morphological features were evaluated by a study of paraffin embedded sections stained with haematoxylin and eosin stains. Immunohistochemical stains for BER-H2 and leucocyte common antigen (LCA) were performed in all cases. The age of the patients ranged from 2 to 60 years and male to female ratio was 2.3:1. Cervical lymphadenopathy was the most common presentation. Histologically, there was a complete effacement of the lymph node architecture in 8 cases. The Reed-Sternberg like cells were seen in 2 and histiocyte like cells in 7 cases. Immunohistochemically all cases were positive for BER-H2. It is suggested that the possibility of Ki-1 lymphoma should be considered in all cases of lymphoma with pleomorphic morphology. 相似文献