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11.
Spatial phase and frequency in motion capture of random-dot patterns   总被引:1,自引:0,他引:1  
A square matrix of spots (A) was presented in rapid alternation with an uncorrelated matrix (B). If the square arrays are superimposed spatially one sees random incoherent motion. However, incoherent motion was seen only if the outer edges were exactly aligned. If the outline of matrix A is shifted horizontally by 1 degree in relation to B, then the edges are seen to oscillate to and fro. Surprisingly, all the dots in the matrix were seen to 'adhere' to the edges and to move horizontally (Ramachandran, 1981). We then aligned the edges again to produce incoherent motion and superimposed a sine-wave grating on the pattern. If the grating was moved horizontally then all the spots 'adhered' to it and moved horizontally as well. This illusion ('motion capture') was optimal (a) at a 90 degrees spatial phase shift of the grating; (b) at low spatial frequencies (less than 0.5 cycles); and (c) when the grating was alternated in step with the dot patterns. Density modulated gratings were just as effective. We conclude that the unambiguous motion signal derived from the grating is applied spontaneously to the dots as well.  相似文献   
12.
Summary A hydrophobic substrate, 10-hydroxydecanoic acid having two functional groups (–OH and –COOH) in the molecule, was polymerized by ester bond formation with the polyethylene glycol-modified lipase in a transparent benzene solution. The polymer of 10-hydroxydecanoic acid was linearly elongated under a quite mild condition.  相似文献   
13.
A previous study demonstrated the preparation of an antiserum having enough specificity and sensitivity for a radioimmunoassay to determine fragment D-dimer derivatives. Using the antiserum the contents of fragment D-dimer derivatives in the sera of normal subjects and patients were determined. The content in normal subjects was 0.260 +/- 0.07 micrograms/ml (mean +/- SD) an that in patients with elevated levels of FDP ranged from 0.30 to 28 micrograms/ml. The values of fragment D-dimer derivatives and FDP in sera of some patients did not necessarily change in parallel, although there seems to be generally a positive correlation between them.  相似文献   
14.
Visible fibrinolysis by endothelial cells: Effect of vitamins and sterols   总被引:1,自引:0,他引:1  
We have succeeded in corroborating the enhancing effect of vitamin A, vitamin C, sitosterol and fucosterol on the fibrinolytic activity of endothelial cells. The assay system consisted of anin situ dissolution of a fibrin layer coated onto a culture dish, over which endothelial cells were grown in a culture medium containing 10 % serum. The dissolution was enhanced by the addition of these vitamins and phytosterols to the culture medium.To whom correspondence should be addressed.  相似文献   
15.
Summary A ferromagnetic modifier was prepared by reacting ferrous(Fe2+)- and ferric(Fe3+)-ions with polyethylene glycol having two carboxyl groups (MW:2000) at pH 8.0–8.5. Lipase fromPseudomonas fragi 22–39B was coupled with the modifier using water-soluble carbodiimide. The modified lipase, which was dispersed into buffered solutions in the size range of 30–70 nm, exerted the hydrolytic activity of 8.0 U/mg. In a magnetic field of 250 Oe, the ferromagnetic-modified lipase was readily recovered from the colloidal solution.  相似文献   
16.
Amino groups of batroxobin (Bothrops atrox thrombic protease) were modified with 2,4-bis(O-methoxypolyethylene glycol)-6-chloro-s-triazine (activated PEG2). The modified batroxobin had the reduced binding ability towards anti-batroxobin antibody but retained its enzymic activity in vitro and in vivo. Administration of modified batroxobin in which 29% of the total amino groups in the molecule had been modified, to beagle dogs preimmunized with native batroxobin gave rise to a marked reduction of the fibrinogen level in plasma, accompanied with an increased level of fibrinogen (fibrin) degradation products, FDP. On the other hand, no reduction of fibrinogen level was observed when native batroxobin instead of modified batroxobin was injected to immunized dogs.  相似文献   
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