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The features that Magic Lite products offer as an immunoassay delivery system are discussed. The use of paramagnetic particles and acridinium ester labels confers advantages of speed, sensitivity, and stability. The technology has been used to measure analytes of widely varying molecular weights and serum concentrations, indicating its potential to detect the full range of clinically relevant analytes. Initial development efforts have indicated that the advantages of the system can be effectively exploited in an automated instrument. 相似文献
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The electric heart activity can be localised from body surface mapping data with computer algorithms. At higher heart rates the T and P waves merge. Thus, the offset can not be subtracted in the TP segment. We investigated 28 healthy volunteers with signal averaged 31-lead magnetocardiography. The offset of the baseline was determined in the TP-segment and in the PR-segment, respectively. The electrical heart activity was localised in the initial 30 ms of the QRS complex (Q), at the QRS maximum (R), and at the T wave maximum (T). The volume currents were considered by using a boundary element model with the compartments lungs and torso. The 3D positions of the dipoles, the dipole orientations, and the dipole strengths were calculated using the data preprocessed with two different offset correction intervals. The offsets of the TP and PR segments significantly differed one from another. The average deviations of the dipole localisation were within a few centimetres (Q: 20 +/- 31 mm, R: 6 +/- 13 mm, T: 14 +/- 30 mm). However, in a small number of subjects (Q: n = 5, R: n = 2, T: n = 5) we observed a deviation of more than 30 mm. These deviations were not linearly correlated to the differences in the baseline offsets. High resolution recordings continuously detect heart activity in the PR segment. The correction of the baseline in the PR segment instead of the TP segment may introduce artefacts in the source localisation and therefore should be avoided. 相似文献
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The present study was designed to identify the physicochemical, immunologic, and biologic properties of the immunoreactive glucagon (IRG) moieties of canine gastric fundus and to compare them with those of the canine pancreas. Acid-alcohol extracts of the gastric fundus and pancreas of dogs were subjected to Bio-Gel P-10 chromatography, The elution profiles of extracts of both organs revealed IRG peaks in the Mr = 2,000 3,500, and 9,000 zones; in the gastric extracts, a void volume peak was also present. On the basis of Sephadex G-150 rechromatography and sucrose density gradient ultracentrifugation the latter IRG was estimated to have a Mr = 65,000. Incubation of fundic IRG65,000 in 8 M urea failed to alter its elution position. Its pI was 6.4, while fundic IRG3,500 had a pI of 6.15 and pancreatic glucagon 6.25.Fundic IRG9,000 had a pI of 4.5 and pancreatic IRG9,000 4.65. Dilution curves of these three fundic and two pancreatic IRGs were parallel to crystalline beef-pork glucagon. The glycogenolytic activity of fundic IRG3,500 and IRG65,000, measured in the isolated rat liver system, was not different from that of immunoequivalent amounts of dog pancreatic glucagon or crystalline beef-pork glucagon. Both fundic and pancreatic IRG9,000 were devoid of glycogenolytic activity and lacker adenylate cyclase stimulating activity and 125I-glucagon displacing activity when tested on partially purified rat liver membranes. Fundic IRG65,000, however, stimulated adenylate cyclase and displaced 125I-glucagon to the same degree as immunoequivalent amounts of pancreatic glucagon. Fundic IRG3,500 was more active than pancreatic glucagon in stimulating adenylate cyclase activity. This was not clearly attributable to differences in binding to liver cell membranes. 相似文献
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Ultrastructural demonstration of NAD-pyrophosphorylase activity (E.C.2.7.7.1) in isolated mouse liver nuclei was investigated with the use of an electronhistochemical procedure based on the precipitation of pyrophosphate ions with lead ions under conditions permitting simultaneous ATPase inhibition by formaldehyde/ethanol prefixation. In isolated mouse liver nuclei activity of NAD-pyrophosphorylase was found in nucleoli, in interchromatin granules, coiled bodies and strand-like structures in nucleoplasm. 相似文献
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Ultrastructural localization of some oxidative and dephosphorylating enzymes was investigated in isolated rat and mouse liver nuclei and in nuclei isolated from various rat hepatomas. In the discussion the significance of changes in the activity of these enzymes in neoplastic cells is considered. 相似文献
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K. Unger 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1959,29(7):289-293
Ohne ZusammenfassungMit 8 AbbildungenQuedlinburger Beiträge zur Züchtungsforschung Nr. 43. 相似文献
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Prof. Dr. F. Unger 《Plant Systematics and Evolution》1851,1(16):125-127
Ohne Zusammenfassung 相似文献
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