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21.
A chemiluminescence technique (CLT) has been developed which measures the interaction between human monocytes and antibody-coated (opsonized) platelets. This technique has an objective end-point, is simple to perform and is of comparable sensitivity to the platelet suspension immunofluorescence test (PSIFT) when used to detect anti-platelet allo-antibodies. In contrast, only 4/20 sera from patients with clinically diagnosed autoimmune thrombocytopenia were opsonic in the CLT, while 8/20 of these same sera bound IgG to platelets in the PSIFT. Only one serum gave positive results in both tests. 相似文献
22.
M F Beersma J M Galama H A Van Druten W O Renier C J Lucas J G Kapsenberg 《International journal of epidemiology》1992,21(3):583-588
Since 1976, when general immunization against measles was introduced in the Netherlands, all new cases of subacute sclerosing panencephalitis (SSPE) were registered and detailed data about immunization, epidemiology and disease progression were collected on them. Up to 1991, 99 new patients have been registered of which 81 were born in this country and 18 elsewhere. From 1981 onwards, the incidence of SSPE among those born in the Netherlands decreased gradually from 13 cases per year to one case per year. This decrease is attributed to the large scale of immunization against measles. Three SSPE patients had been immunized against measles, all of them without a history of clinical measles. Epidemiology and risk factors of SSPE did not differ from those reported in other countries. An exceptional cluster of four patients in one town, who had measles in the same year, is reported. Progression of SSPE appeared to be age related. A total of 28 patients was treated with Inosiplex; no significant effect on survival in stage 3 of the disease was found. 相似文献
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Prediction of choledocholithiasis using a pocket microcomputer 总被引:4,自引:0,他引:4
T V Taylor C P Armstrong S Rimmer S B Lucas J Jeacock A A Gunn 《The British journal of surgery》1988,75(2):138-140
A computerized method, using a small pocket computer, has been used to predict the presence of choledocholithiasis in a prospective series of 239 patients undergoing cholecystectomy. From an initial data base of 424 patients 36 factors were evaluated and the most important 2 of these were determined by multivariate analysis for use in the prospective analysis. Satisfactory operative cholangiograms were a prerequisite to evaluation of the statistical method and were obtained in 90.4 per cent of cases. Using the computerized method a common bile duct stone would have been overlooked in only 1 patient but 17 unnecessary explorations would have been carried out. The overall accuracy of the computerized method was 92.5 per cent. When the method was applied to a further study of 97 patients from a separate centre the overall accuracy was 85.6 per cent. If the method was used to aid selective use of operative cholangiography, cholangiograms would be performed in 20 per cent and stones would be overlooked in less than 1 per cent. 相似文献
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A case of adrenal hemangioma is reported, displayed by computed tomography and confirmed by pathologic investigation. This rare tumor poses a difficult diagnostic challenge and rejoins the problem of incidentally discovered adrenal masses. 相似文献
27.
Factor VIII assays. Assessment of variables 总被引:1,自引:0,他引:1
J T Brandt D A Triplett K Musgrave C Arkin E G Bovill F V Lucas W A Rock 《Archives of pathology & laboratory medicine》1988,112(1):7-12
Factor VIII assays are the most common specific coagulation factor assay performed in the United States. Interlaboratory proficiency studies have documented persistent problems with variation in results between laboratories. The Coagulation Resource Committee of the College of American Pathologists conducted a workshop to analyze variables that may affect performance of the one-stage factor assay. The results indicate that accuracy of the assay can be improved by uniform standardization of reference plasma samples and that reproducibility can be enhanced through appropriate choice of reagents and instruments. Optimizing performance of this assay should lead to more reproducible interlaboratory results. 相似文献
28.
Altered patterns of reflex excitability subsequent to contusion injury of the rat spinal cord. 总被引:5,自引:0,他引:5
1. The present study investigated regulation of reflex excitability after experimental contusion injury of the spinal cord. 2. Four measures of H-reflex excitability were evaluated in normal rats and at 6, 28, and 60 days after contusion injury at the T8 level: 1) reflex thresholds, 2) slope of the reflex recruitment curves, 3) maximal plantar H-reflex/maximal plantar M-response (Hmax/Mmax) ratios, and 4) rate-sensitive depression (i.e., the decrease in reflex magnitude relative to repetition rate). 3. Tested as a function of the afferent volley magnitude, the thresholds for reflex initiation fell progressively subsequent to contusion injury. No change was observed at 6 days postinjury, and the decrease at 28 days was not significant. However, by 60 days postinjury, the threshold had decreased by 23% of the maximal afferent volley, and this decrease was significant, [analysis of variance (ANOVA, P < or = 0.01)]. 4. Hmax/Mmax ratios elicited in postcontusion animals at 0.3 Hz were not significantly different from those recorded in normal animals. 5. The slopes of the recruitment curves were markedly reduced subsequent to contusion injury. The decrease was greatest at 6 days postinjury. Although some recovery toward normal occurred at 28 and 60 days postinjury, the slopes of recruitment curves in postcontusion animals remained significantly decreased. 6. H-reflexes elicited at 1-5 Hz were less sensitive to rate depression in postcontusion animals than in normal animals at the same respective frequencies. The decrease was progressive in onset, becoming significant by 28 days postinjury, and of an enduring nature, i.e., still significantly different from normal in the reflexes tested 60 days postinjury. 7. Rate sensitivity of the tibial nerve monosynaptic reflex (MSR) was also compared in normal and postcontusion animals. Rate sensitivity of the tibial MSRs was significantly reduced at 28 and 60 days post-contusion, compared with normal animals. 8. These data indicate that significant changes in lumbar reflex excitability result from midthoracic contusion injury of the spinal cord. These changes include reflex threshold, slope of recruitment, and rate-sensitive depression. Although recruitment slope was most altered in the shortest postinjury interval tested, followed by some recovery, the other changes were progressive in onset and enduring in duration. 相似文献
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