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991.
In this new radioimmunoassay system for determination of amatoxins in urine and plasma, a novel chemical approach is used for antigen and 125I-tracer production, based on a detoxified alpha-amanitin derivative (aldoamanitin). Total assay time, including data processing, is less than 100 min. The lowest detectable concentration is 1 microgram/L for urine, 0.1 microgram/L for plasma. In the clinically significant range, within-run CVs are less than 8%. This new 125I-based assay is a significant improvement over existing 3H technology in terms of speed, precision, and freedom from interference. 相似文献
992.
993.
D J Brooks J S Gibbs P Sharp S Herold D R Turton S K Luthra E M Kohner S R Bloom T Jones 《Journal of cerebral blood flow and metabolism》1986,6(2):240-244
Regional cerebral [11C]3-O-methyl-D-glucose ([11C]MeG) uptake kinetics have been measured in five insulin-dependent diabetic patients and four normal controls using positron emission tomography (PET). Concomitant measurement of regional cerebral blood volume and CBF enabled corrections for the presence of intravascular [11C]MeG signal in cerebral regions of interest to be carried out, and regional cerebral [11C]MeG unidirectional extraction fractions to be computed. Four of the five diabetic subjects were studied with their fasting plasma glucose level clamped at a normoglycaemic level (4 mM), and four were studied at hyperglycaemic plasma glucose levels (mean 13 mM). The four diabetic subjects whose fasting plasma glucose levels were clamped at a normoglycaemic level of 4 mM had mean fasting whole-brain, cortical, and white matter [11C]MeG extraction fractions of 15, 15, and 16%, respectively, values similar to those found for the four normal controls (whole brain, 14%; cortex, 13%; white matter, 17%). Mean regional cerebral [11C]MeG extraction fractions were significantly reduced in diabetic subjects during hyperglycaemia whether their plasma insulin levels were undetectable or whether they were raised by continuous intravenous insulin infusion. Such a reduction in [11C]MeG extraction under hyperglycaemic conditions can be explained entirely in terms of increased competition between [11C]MeG and D-glucose for the passive facilitated transport carrier system for hexoses across the blood-brain barrier (BBB). It is concluded that the number and affinity of D-glucose carriers present in the BBB are within normal limits in treated insulin-dependent diabetic subjects. In addition, insulin appears to have no effect on the transport of D-glucose across the BBB. 相似文献
994.
Zusammenfassung Anhand von 9 Abbildungen wird eine Methode zur Kehlkopfpräparation beschrieben, bei der sämtliche Knorpel, Gelenke und Muskeln dargestellt werden. Nach Ablösung des Schildknorpels und des Hypopharynx werden die Mm. postici und arytaenoidei isoliert, die Cricoarytaenoidgelenke sowie die Arytaenoidknorpel präpariert und die Mm. laterales eingeschnitten. Ein Horizontalschnitt durch den Ringknorpel und die median-sagittale Spaltung des proximalen Fragmentes liefern schließlich den Zugang zu den inneren Kehlkopfweichteilen. 相似文献
995.
Neurosyphilis today is a rare problem. We describe a man who presented with organic brain syndrome, psychosis and incontinence, and diagnosis was neurosyphilis with resultant bladder dysfunction. Urodynamic studies defined the voiding dysfunction as detrusor areflexia with a positive bethanechol test. This case reminds us of the necessity of obtaining a test for venereal disease to rule out neurosyphilis in patients with idiopathic voiding dysfunction. 相似文献
996.
997.
A case of a pedunculated arachnoid cyst within the third ventricle is presented. The cyst was small so as not to appear as a significant expanding lesion on CT. The clinical history, however, suggested intermittent increase of the intracranial pressure. On CT there was some widening of the lateral and third ventricles, while the fourth ventricle had normal width. This finding in combination with the clinical history prompted further neuroradiologic examinations, including pneumoencephalography and ventriculography. The presence of a pedunculated mobile cystic lesion within the third ventricle was shown and its nature further elucidated by stereotactic puncture combined with contrast injection into the cyst. After emptying of the cyst, the patient has been free of symptoms during an observation time of 2 years. The diagnostic and differential diagnostic aspects are discussed and the value of traditional neuroradiologic methods emphasized. 相似文献
998.
Two hundred and seventy-seven patients with advanced prostatic cancer were treated by either orchiectomy or oestrogen. During the 2-year follow-up period, the response to treatment was considered more favourable in the oestrogen group, and this response was particularly emphasised in patients with poorly differentiated tumour and metastases at the time of diagnosis. Further evaluations included the cardiovascular side effects of oestrogen therapy. 相似文献
999.
The possible role of nerve activity in triggering changes in the localization of acetylcholine receptors (AChRs) and cholinesterase (ChE) on nerve-contacted Xenopus muscle cells has been assessed. The localization of these molecules was examined on nerve-contacted and noncontacted muscle cells in cultures of spinal cord and myotomal muscle derived from Xenopus embryos. Sites of high AChR density were revealed by staining with fluorescent alpha-bungarotoxin and sites of ChE localization were revealed histochemically. Localization of AChRs and ChE at sites of nerve-muscle contact occurred when the culture medium contained 1.2 micron tetrodotoxin (TTX), 1.2 micron TTX, 10 mM magnesium, and no calcium salts, 1.2 micron TTX and 2 mM manganese, or 106 mM potassium methyl sulfate instead of sodium chloride. The nerve-contacted muscle cells in each of these modified culture media also exhibited a reduced incidence of AChR and ChE patches away from the site of contact. It is concluded that the neural factor(s) that triggers the local and remote changes in AChR and ChE distribution can be supplied to the neurites and externalized in the absence of nerve impulses, and that the nerve and muscle cells can interact even when they are largely depolarized. 相似文献
1000.
We studied the relationship between arterial carbon dioxide tension (PaCO2) and fresh gas flow (FGF) during use of the Bain breathing circuit for Caesarean section anaesthesia. Thirty-one patients undergoing Caesarean section were anaesthetised using the Bain circuit with intermittent positive pressure ventilation. The PaCO2 were measured at FGF of 70 ml X kg-1 X min-1, 80 ml X kg-1 X min-1, and 100 ml X kg-1 X min-1. The FGF requirement to maintain a given PaCO2 during Caesarean section anaesthesia is the same as the requirements for nonpregnant subjects, despite the increase in carbon dioxide production associated with pregnancy. This is probably because the total FGF determined by body weight and given during Caesarean section anaesthesia is 15-20 per cent higher than nonpregnant levels, due to the weight gain associated with pregnancy. A FGF of 100 ml X kg-1 of pregnant weight/min maintains PaCO2 of 4.44 kPa predelivery, which is in the desirable range of PaCO2 during Caesarean section. 相似文献