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891.
892.
Digital volume tomography (DVT) is an extension of panoramic tomography. With this diagnostic technique, characterized by high resolution, a narrow section width (0.125 mm) and three-dimensional display, small pathological processes can be well visualized. Twenty-five patients with the history of a progressive hearing loss were examined with DVT (Accu-I-tomo, Morita, Japan). The results were compared with pre- and intraoperative findings to evaluate the diagnostic value of DVT in cases of erosion of the ossicular chain. With high resolution and artifact-free demonstration of the middle ear and the ossicular chain, it was possible to define its continuity preoperatively by DVT in all 25 cases. An intact ossicular chain was found by DVT in 13 cases and was later confirmed by surgery. The predicted erosion of the ossicles was verified in 12 patients, and a tympanoplasty type III was performed. Digital volume tomography is an excellent technique to examine the middle ear cleft and inner ear, and expands the application of diagnostic possibilities in the lateral skull base. Therefore, improvement in preoperative diagnosis is achieved along with more accurate planning of the surgical procedure. Digital volume tomography delivers a small radiation dose with a high resolution and a low purchase price for the equipment.  相似文献   
893.
894.
A scheme of physicochemical determination of fibrinogen and the major molecular derivatives in a single sample of plasma is suggested, available for the majority of clinical laboratories. Such determination gives valuable information for a clinician. Among other things, the level of rapidly thrombin clotted fibrinogen portion is determined, as is the content of high-molecular fibrin monomer complexes, not clotted with thrombin, and the level of fibrinogen and fibrin proteolytic degradation products. Clinical (in 42 patients with various conditions) and experimental (coagulopathy in amniotic fluid embolism) application of this scheme has confirmed its clinico-diagnostic value.  相似文献   
895.
896.
Vibrio cholerae induced auxotrophic variants nonfermenting several carbohydrates simultaneously have been obtained for the first time. Eltor vibrio clones have been selected, referred to Heuberg's groups V and VI by their enzymic activities. The findings of the present study evidence that, when isolating Eltor vibrio strains negative towards differential carbohydrates, in case of a positive agglutination test, the incubation period should be prolonged to 3 days. The principal differential diagnostic test for this species, when cholera is bacteriologically diagnosed, should be a positive volumic agglutination test with species- and variant-specific sera, irrespective of Heuberg's group.  相似文献   
897.
We report the evaluation of four new commercially available sensitive assay kits for determination of thyrotropin (TSH) and their clinical utility in normal subjects and patients with thyroidal and non-thyroidal illnesses. The sensitivity for the reliable detection of serum TSH by these methods ranged from 0.1-0.4 mU/L and their decreasing order was : NML greater than Serono greater than Abbott EIA greater than Hybritech. The coefficient of variation ranged from 2.0-5.8% for intra-assay and 2.3-8.6% for interassay at different concentration levels. Patients studied (n = 130) were assigned into four groups on the basis of the serum thyroxine value and their clinical findings. In total, there were 17 discrepancies (five with Hybritech, three with NML, five with Abbott EIA, and four with Serono) in making the correct diagnosis using these sensitive TSH methods as a single diagnostic test. These discrepancies were mainly in the same patients who were clinically euthyroid but had subnormal TSH values. There were no discrepancies in making the correct diagnosis for patients with hyperthyroidism or hypothyroidism using these sensitive TSH methods. Our observations indicate that the sensitive TSH methods are reliable in measuring subnormal levels and may be used to detect hyperthyroidism without affecting in any way their value in detecting hypothyroidism.  相似文献   
898.
Radioisotopes have been used for many years in the diagnosis of vascular abnormalities. In some areas the technique is regarded as routine and essential, while in others its place is less certain. This is often the case because of competition from other diagnostic methods or the facility may not be readily available. With the active participation of the Department of Nuclear Medicine, radionuclides can be used to provide information in both clinical diagnosis and laboratory investigation. It is intended to emphasise those areas where the method appears to have a rewarding clinical application.  相似文献   
899.
Translated from Khimiko-farmatsevticheskii Zhurnal, Vol. 23, No. 11, pp. 1349–1352, November, 1989.  相似文献   
900.
An apparatus for the measurement of reaction time to both visual and auditory stimuli with a provision to vary intensity of stimuli and with facility for lateralisation of sound to the right or left ear has been described.  相似文献   
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