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991.
Non-invasive transcranial Doppler US investigation in adult patients was first described by Aaslid et al. (1982). The apparatus consists in a 2 MHz bidirectional pulsed Doppler with spectrum analyser. Middle and anterior cerebral arteries were insonated by transtemporal exploration, basilar artery by occipital foramen. The criteria of identification were: position and angulation of the probe, direction of the flow, depth of sample volume. The authors present a first series of 31 patients, all with cervical CW Doppler and B-mode Echo. The percentage of identification was: MCA 72%; ACA 69%; BA 54%. Some clinical cases are illustrated. The interest of the method is emphasized in spite of constraints depending on probe position and anatomical variability of the circle of Willis: ambulatory and non-invasive methods; assessment of intracranial blood flow in various conditions: cerebral ischemia and infarction, intracerebral angioma; complementarity with other non-invasive and non-expensive techniques: EEG and cervical US investigation.  相似文献   
992.
It is well known that perimetric findings fluctuate within a single examination. There is additional fluctuation between perimetric examinations. The cause of this fluctuation is not yet fully understood, but such things as changes in attention, patient cooperation, or drugs have been discussed. To study such possible factors, we carried out perimetry on subjects who had consumed alcohol and who had not. The results indicate that alcohol, at a blood concentration of approximately 0.08%, barely influences the results of static automated perimetry. Differential light sensitivity remained unchanged by alcohol at all eccentricities tested. A decrease in the ability to cooperate was manifested by a significant higher score of false-positives in catch trials. There was also a tendency toward an increase in false-negative responses in catch trials, an increase in the number of stimuli presentations required, and higher short-term fluctuation. Lack of the influence of alcohol on the differential light threshold does not necessarily mean that alcohol has no influence on visual function. It indicates, however, that differential light sensitivity, as measured with the automated perimeter Octopus, is not influenced by moderate alcohol ingestion.  相似文献   
993.
994.
Input-output (I/O) functions of hearing aids were measured in response to a 2000-Hz tone burst, having 0.5 ms rise/fall time and 10 ms duration. I/O functions, measured with a hearing-aid analyzer, served as reference conditions. Hearing-aid outputs at onset and during the steady-state portion of the waveform differed; these differences often depended upon stimulus rate. The relation between onset and steady-state estimates of output were not always predictable from hearing-aid attack and release times. These findings indicate that the steady-state output limitation characteristics of hearing aids cannot be estimated from their onset responses. In turn, this suggests that ABR measurements may not provide accurate estimates of the compressive characteristics of hearing aids.  相似文献   
995.
In the present paper, the results obtained are shown after a study by means of multivariant statistical analysis, of the quantity of Eimeria spp. oocyst elimination in sheep, bearing in mind the variations observed in the different areas, in the different age-groups, from month to month, and from year to year. Climatic factors, development of immunity, lambing seasons, and poor hygienic conditions seem to be the factors responsible for the statistically significant differences found when analysing the aforementioned main effects.  相似文献   
996.
997.
Although silicones, as a class, are nontoxic in animal and tissue studies, implanted silicone prostheses and medical devices are associated with various local and systemic host inflammatory reactions. They also have been associated with a form of autoimmune disease. To test the hypothesis that silicones may evoke an immunologically mediated inflammatory reaction, 10 guinea pigs were stimulated for 1 month with intraperitoneal injections of sterile medical-grade silicone oil admixed with homologous serum and complete Freund's adjuvant. Ten controls were stimulated with saline. Four additional animals were passively sensitized with splenic homogenates from four sensitized animals. Intradermal antigenic challenges consisted of silicone-homologous serum, pure silicone, saline-homologous serum, and purified protein derivative. Cutaneous reaction patterns were graded grossly and microscopically. Silicone-serum and purified protein derivative antigens evoked three to four times greater palpable lesions in all 10 actively and all 4 passively sensitized animals at approximately 24 h compared to controls. Biopsies showed a moderate to marked lymphocytic infiltrate. Control sites and naive animals showed only edema at the challenge sites. The data suggest that silicone-protein complexes are potentially immunogenic.  相似文献   
998.
999.
Lymphocytes from 10 paired colostrum and peripheral blood specimens were examined to determine if the colostral T cell population differs from the peripheral blood T cell population in subset distribution. The percentages of lymphocytes staining with OKT3, OKT4, and OKT8 murine monoclonal antibody were determined. Lymphocytes from colostrum were 74.7 +/- 2.5% OKT3+, 50.6 +/- 2.3% OKT4+, 24.0 +/- 1.7% OKT8+, whereas peripheral blood lymphocytes were 78.7 +/- 1.9% OKT3+, 48.4 +/- 1.4% OKT4+, and 29.8 +/- 1.6% OKT8+. The percentage of colostrum lymphocytes positive for OKT3 was significantly although not strikingly lower than the OKT3 percentage for blood lymphocytes (p less than 0.05). This difference was due to the lower percentage of OKT8 positive lymphocytes in colostrum compared with blood (p less than 0.01). Although the T cell subset distribution of colostrum generally appears to be similar to that in the peripheral blood, there were small differences in OKT3 and OKT8 percentages that were statistically significant suggesting the possibility of some selectivity of the colostral T cell population.  相似文献   
1000.
Our research was aimed at establishing if and how selenium (Se) ion, N-acetylcysteine (NAC), sodium salt of monoketocholic acid (MKH) and superoxide-dismutase (SOD), administered in the experimental animal model, could affect the possible cytotoxicity associated with anthracycline-based combined chemotherapy with doxorubicin, vincristine and prednisolone (DVP). The following biochemical parameters were investigated: the extent of lipid peroxidation (LPx), and the activity of peroxidase (Px), catalase (CAT), glutathione-peroxidase (GSHPx), and xanthine-oxidase (XOD). A statistical increase in LPx activity was obtained by SOD, MKH, DVPSe and DVPMKH. All chemotherapeutic agents reduced Px activity in a statistically significant manner. There was no statistical significance for the results regarding the effects of the administered substances on GSHPx activity. The results for DVP, SOD, MKH, DVPSOD, DVPSe and DVPMKH showed reduced XOD activity which was statistically significant, which was lowest in the case of MKH, while NAC and Se reduced the activity of this enzyme but statistically non significant. NAC, Se, DVP, MKH and DVPMKH caused a reduction in CAT activity, while DVPSOD and DVPSe caused an increase of the latter.  相似文献   
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