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The existing technology of water production cannot protect injections and solutions from foreign substances. The main ways of the solution contamination are: microbiotic pollution of distilled water, air and manmade pollution. The article deals with a problem of removing pyrogenic substances from parenteral solutions. A special attention is paid to the methods of electrofiltration and ultrafiltration by means of a membrane filter (Soviet production). The authors emphasize the importance of a strict control over pyrogenic tests of injections. The appropriate factory facilities and essential hygienic and sanitary conditions in manufacturing injections will rule out the possibility of its microbiotic pollution.  相似文献   

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A simple method for improving the quality of electronic portal imaging device (EPID) portal images was proposed for the reduction of the burden on the registration between digital reconstruction radiography (DRR) and EPID portal images in radiation therapy. Conventional image filtering techniques in the spatial-frequency domain are applied to the proposed method. While a band-pass filter (BPF) is employed to extract spatial-frequency components included in the bone edge, a high-pass filter (HPF) is employed to obtain the effect corresponding to the general dynamic range compression. The band-pass filtered image is weighted by a parameter for adjusting the bone edge enhancement, and is added to the high-pass filtered image. This method was applied to the portal images in the neck region. In the image obtained by the proposed filtering, the bone edge was clearly observed. In addition, soft tissue structures were identified in the same display settings (window level/width; WL/WW) as the bone edge observation; that is, the adjustment of the display settings was not required for the observation of each object. These results suggested that both bone edge enhancement and dynamic range compression would be achieved successfully. It was estimated that the images obtained by the proposed method were more appropriate for the registration than conventional portal images, in 47 times registrations of 50 times in total (the registrations by five radiological technologists in ten patients). The proposed method was concluded to be useful for improving the quality of portal images, enabling the efficient registration.  相似文献   

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The evaluation is carried out of a simple filtering routine for improving the detectability of low contrast lesions in bone scans. With this routine, the unprocessed image is displayed together with three filtered versions, the final decision on the presence of abnormalities being made by comparing the four images. Emphasis is placed on producing a routine which is quick in implementation and, therefore, only small filter arrays are used. Using a routine consisting of a low-pass, a median, and a differential filter, 73% more lesions are detected when the filtered images are also used. The whole routine takes less than 1 min to run.  相似文献   

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By definition, haemodilution involves the use of filling solutions, but in this technique the role of different solutions has yet to be clearly defined. Amongst the criteria of choice used at the present time, two would seem to be essential: good tolerance, limiting the risks of complication and side effects to an absolute minimum; and a sufficiently long intravascular half-life ensuring good control of blood volume. On this basis, amongst the crystalloids Ringer lactate offers definite advantages. It is almost always used in association with a colloidal solution, very often human albumin or a dextran.  相似文献   

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R J Benink 《Radiology》1978,128(2):508-509
The author describes a localizing device which permits accurate placement of x-ray sources in relation to both the patient and the cassette. Radiographs can be reproduced exactly using this device.  相似文献   

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G D Reyes 《Radiology》1990,176(3):863-864
A device was designed to facilitate placement of biopsy needles with computed tomographic guidance. The device consists of a hollow, clear plastic disk filled halfway with fluid and a central stem with a groove for the needle. When the device is rotated, the air-fluid level points to the corresponding angle marked on the side of the disk. In a phantom study, 17 of 20 passes were within +/- 3 degrees of the anticipated angle of entry, and the remaining three were within +/- 5 degrees. The device was also used in 14 patients; the resultant angle of entry was within +/- 3 degrees of the anticipated angle.  相似文献   

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