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51.
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Computerized tomograms were studied of 67 adults whose lumbar pneumoencephalograms were normal or showed ventricular dilatation with or without widening of the sulci. The maximum ventricular area, measured from 80 x 80 matrix printouts, correlates well with measures of ventricular size on the pneumoencephalogram. An area of 10 cm2 is suggested as the upper limit of normal. The correlation between measures of sulcal width on computerized tomography and pneumoencephalography is less precise, but normal sulci and gross degrees of cortical atrophy can be identified.  相似文献   
53.
Apparent total alpha1-antitrypsin deficiency: report of a case   总被引:1,自引:0,他引:1  
A 29-year-old female, with chronic renal failure and chronic bilateral emphysema, was admitted with severe uremia and septicemia secondary to multiple abscesses in the right kidney. Her condition improved after right nephrectomy. Pulmonary function studies showed marked obstructive and restrictive lung disease consistent witht the diagnosis of primary emphysema. On biochemical and histological examination, the liver was found to be normal. Alpha1-antitrypsin could not be demonstrated in the patient's serum at normal pH by any of the known techniques, but protein molecules with alpha1-antitrypsin antigencity were found at pH 4.8; this suggests a pH-dependent structural difference in alpha1-antitrypsin protein. Starch gel electrophoresis gave a multibanding pattern not previously described. A new form of apparent total alpha-1-antitrypsin deficiency is postulated.  相似文献   
54.
Long tube implants in the management of glaucoma   总被引:2,自引:0,他引:2  
The design, surgical insertion and results of a plastic draining implant for severe glaucoma are reported. The need for pharmacological control of bleb inflammation is stressed and the favourable long-term outlook for patients with such implants is discussed.  相似文献   
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Identification and fractionation of plant histones   总被引:4,自引:0,他引:4  
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The study of cooperative ligand binding among the four subunits of haemoglobin has played a central role in the understanding of allosteric transitions in a large number of enzymes. Haem iron out-of-plane motion has been suggested to be the trigger for the cooperative transition of haemoglobin. To function as a trigger in a dynamic sense, haem-iron doming must be the first conformational change to occur following ligand dissociation. Here we present the first direct demonstration that haem-iron doming occurs on the same time scale as the breaking of the iron-ligand bond, thus establishing haem-iron doming as the primary event which lead to the R-->T transition in haemoglobin.  相似文献   
59.
BACKGROUND: The increase in frequency of peanut allergy and fatal cases have been reported. OBJECTIVES: The objective of this study is to document the severity of food allergy to peanuts by evaluating the reactive dose of peanuts and to search for the role of peanut oil. METHODS: This study is carried out on the basis of 142 observations collected according to the same diagnostic methodology in two allergy centres in France. Skin-prick-tests were performed with peanut powder, peanut oil and peanut oil proteinic extract. Labial provocation tests were performed on 121 patients. The reactive dose of peanuts and the role of peanut oil were determined by standardized oral provocation tests in 50 and 62 patients respectively. The data are computerized and the data bank includes 509 food allergic patients. RESULTS: Allergy to peanuts represents 28% of food allergies and occurs under 1 year of age in 46% of cases, under 15 years of age in 93%. The clinical features were atopic dermatitis (40%), angioedema (37%), asthma (14%), anaphylactic shock (6%) and digestive symptoms (1.4%). The specific IgE were class 3 or higher in 80% of cases. The total reactive dose was less than 100 mg in 25% of cases, from 100 mg to 1 g in 62.5%. All patients reacted to a dose of less than 7.1 g. The threshold of peanut reactivity was lower than the threshold of egg reactivity. An allergy to peanut oil was demonstrated in 14 patients. CONCLUSION: The severity of peanut allergy and the early onset of the occurrence of this allergy is documented. The role of residual allergenic proteins in peanut oil is established by positive skin-prick tests to proteic extracts from peanut oil and by double-blind placebo-controlled challenges to peanut oil. The increased consumption of allergens in the form of peanut oil and fats can contribute to the occurrence or persistence of symptoms and may be suspected to increase the risk of sensitisation.  相似文献   
60.
Acquired arachnoid cysts of the spinal cord are uncommon causes of spinal cord compression in the pediatric group. Meningitis, trauma and hemorrhage are considered to be causative or contributing factors. Interestingly, no spinal arachnoid cysts have been reported in patients after subarachnoid hemorrhage or meningitis, conditions expected to cause arachnoid scarring. We describe a child of 1 year and 10 months with thoracic spine trauma with crural paraplegia and anesthesia at level T5 submitted to serial magnetic resonance imagery at 5 days and 18 months, after trauma showing evolution from subarachnoid hemorrhage and adhesions of the arachnoid space to a posterior hypertensive thoracic intradural arachnoid cyst.  相似文献   
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