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91.
The biotransformation of oxazepam by Bifidobacterium bifidum was studied. The major metabolite was purified by chromatographic methods and found to be desmethyldiazepam using NMR, IR and other physicochemical data.  相似文献   
92.
According to some ultrastructural studies, the pericapillary axon terminals in the central nervous system (CNS) are functionally connected with the capillary vessel wall. Thus, it may be expected that the population of pericapillary axon terminals will be morphologically distinct from the terminals at a further distance from the capillary walls. To test this hypothesis, morphometrical analysis of 3,048 axon terminals was performed, comparing terminals situated in the close vicinity of the capillary vessel with those at a distance from the vessels in the lateral, basal, medial, central and cortical nuclei of the amygdaloid body of eight cats. The cross-sectional area and circumference of each identified axon terminal profile were measured, and the shape of synaptic vesicles and the presence of synaptic contacts and granular vesicles were recorded. The statistical evaluation of results was performed by means of the Newman-Keuls' test, Wilcoxon's test, Fisher's contingency-table test and the test for two coefficients of structure. The morphometric examination revealed two ultrastructurally distinct groups of axon terminals, pericapillary and distant terminals, in all the nuclei of the amygdaloid body. The differentiating features were the shape of the synaptic vesicles, the number of synaptic contacts, and the size of the axon terminals. These results further support the hypothesis of a functional connection between axon terminals and the capillary vessel wall in the CNS.  相似文献   
93.
A review of isolates of Neisseria meningitidis and other laboratory evidence of meningococcal infection was carried out for the period 1990-1995. Thirty-three patients with evidence of meningococcal disease were identified over the six year period. Group B organisms were the most commonly identified, but an increase in Group C has occurred and is almost equal in number. Data from clinical, laboratory and public health sources should be centralized in a National Surveillance Centre.  相似文献   
94.
95.
Foreword     
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96.
97.
Strengthening of concrete prisms using the plate-bonding technique   总被引:5,自引:0,他引:5  
This paper presents the use of fracture mechanics for the plate bonding technique. Plates of steel or carbon-fibre reinforced plastic are bonded with an epoxy adhesive to rectangular concrete prisms and loaded in shear up to failure, what is normally known in fracture mechanics as mode II failure. In this special application a linear and a nonlinear approach are presented. The nonlinear equation derived for a realistic shear-deformation curve can only be used for numerical calculations. However, for simplified shear-deformation curves, the derived formula can be solved analytically. Results from tests, which are compared with the theory, are also presented.  相似文献   
98.
A method is described for experimentally determining the dose rate created in building bricks by incorporated natural radionuclides. It was established using the thermoluminescence dosimetry method that the measured dose rate depends on the detector thickness, the mass of the ceramic product investigated, and the irradiation geometry. The contributions to the measured dose of weakly penetrating α and β radiation and hard ψ radiation are separated, the ratio between them depending on the experimental conditions. Translated from Izmeritel'naya Tekhnika, No. 7, pp. 62–66, July, 1996.  相似文献   
99.
We present the performance of a high-speed gateable vacuum image pipeline, which permits individual images to be delayed and selected from continuous non-repetitive image stream. This device is composed of a vacuum tube equipped with a photocathode at one end, a phosphor screen at the other end, and a system of metal grids in between. Photoelectrons produced by the images focused on the photocathode, are guided by a uniform magnetic field, parallel to the tube axis. By changing the grid potentials, the drift time of the photoelectrons inside the tube can be varied from 0.35 to 1.5 μs. An image can then be selected by an external trigger with a time resolution in the range of 4–30 ns, depending on the delay time. The selected photoelectrons are finally accelerated onto the phosphor screen, set at 10 kV, where they reproduce the desired image. With a magnetic field of 0.1 T, a spatial resolution of 33 lp/mm was obtained. The high spatial and time resolution make this device an interesting tool for high-energy physics and astrophysics experiments, and for high-speed photography.  相似文献   
100.
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