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1.
Plasma levels of plasminogen activators (t-PA, u-PA) and their inhibitor (PAI-1) were studied in patients suffering from Buerger's disease and healthy volunteers before and after 15 minutes of venous occlusion test. The baseline levels of t-PA in group of patients did not differ from those of controls. On the contrary patients with Burger's disease showed a marked increase in u-PA antigen concentrations with concomitant decrease in PAI-1 antigen levels. During venous stasis t-PA antigen concentrations increased in all subjects, however it was much pronounced in controls. Venous occlusion resulted in significant decrease in free PAI-1 levels in the group of patients only. In conclusion, Buerger's disease is associated with the endothelial derangement with increased u-PA release and decreased PAI-1 release, which does not influence the function of fibrinolytic system. The fact that the reduced response of the endothelium to release t-PA after venous stasis goes in parallel with marked decrease in PAI-1 antigen levels seems to suggest that patients suffering from Buerger's disease are not at high risk of intravascular fibrin deposition.  相似文献   
2.
Background :
The BTA test is a latex agglutination assay for the qualitative detection in the urine of analytes that are associated with bladder tumor. We compared the results of the BTA test with those of voided urine cytology (VUC) in patients with bladder cancer.
Methods :
A multicenter trial was performed at 6 institutions. A total of 132 patients with histologically diagnosed bladder cancer were enrolled. Urine samples were split for BTA and VUC testing.
Results :
The sensitivities of the BTA test and VUC were 57.6% and 37.9%, respectively; this difference was significant ( P < 0.001). The BTA test had much higher sensitivity for small, solitary, superficial tumors than did VUC.
Conclusion :
The BTA test is simple to perform, gives rapid results, and is far more sensitive than VUC for detection of bladder cancer. The BTA test has the potential to become an additional tool for detecting bladder cancer.  相似文献   
3.
Fluid-fluid levels in cavernous hemangioma of soft tissue   总被引:3,自引:0,他引:3  
Five cases of cavernous hemangioma with fluid-fluid levels on magnetic resonance imaging and/or computed tomography are reported. The signal characteristics were those of blood and histological analysis of the fluid-fluid levels showed that they were blood-filled cavities in the tumor. Although this finding itself is not specific, it may help in confirming the diagnosis of cavernous hemangioma.  相似文献   
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Previous studies have suggested that CD4+ T lymphocytes shift from the Th1 type to the Th2 type during disease progression in patients with the human immunodeficiency virus type-1 (HIV-1). In the present study, we used a modified method that allowed a direct measurement of intracellular cytokines in CD4+ CD8- T cells. A total of 48 HIV-1-infected (HIV+) and 16 HIV-1-uninfected (HIV-) individuals were studied. The percentages of CD4+ CD8- T cells producing interleukin-2 (IL-2), interferon-gamma (IFN-gamma), interleukin-4 (IL-4), or interleukin-5 (IL-5) in HIV+ and HIV- subjects were 23.6% versus 34.9% (P < 0.01), 13.7% versus 13.2%, 1.3% versus 1.0%, and 1. 2% versus 0.9%, respectively. The population of IL-2-producing cells decreased proportionately with reductions in CD4 counts (< 200/mm3, 200-500/mm3, and > 500/mm3 to 18.0%, 23.5%, and 30.5%, P < 0.05, respectively). There was an inverse correlation between the percentage of IL-2-producing cells and plasma viral load (r = - 0. 446, P < 0.05). However, the percentages of CD4+ CD8- T cells producing other cytokines were not different between HIV+ and HIV-. Our cross-sectional study demonstrated a decrease in IL-2-producing cells but not the Th1 to the Th2 shift in the CD4+ CD8- T cell population in the moderate and advanced stages of HIV-1-infection.  相似文献   
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Mihara H  Ohnari K  Hachiya M  Kondo S  Yamada K 《Spine》2000,25(7):796-800
STUDY DESIGN: A radiographic analysis of elderly patients with cervical spondylotic myelopathy, particularly those with involvement of the C3-C4 level. OBJECTIVES: To elucidate the potential contributors to the higher incidence of pathology at C3-C4 in the elderly. SUMMARY OF BACKGROUND DATA: In this study, the elder patients showed a greater predilection for involvement of the C3-C4 lesion compared with their younger counterparts. No previous study has addressed C3-C4 pathology in elderly patients. METHODS: This study included 18 patients, 10 men and 8 women, with cervical spondylotic myelopathy caused by C3-C4 disorders (group I). For the purpose of comparison, 18 younger patients (less than 50 years of age) with myelopathy (group II) and 30 volunteers over the age of 65 (group III) were also investigated. Mean age at admission was 73.5 years for group I, 42.4 years for group II, and 73.4 years for group III. Radiographic analysis, using static and dynamic radiographs, was performed to evaluate the morphologic features. RESULTS: The mean spinal canal diameter for groups I and II was significantly smaller than that for group III. Group I exhibited greater C2-C7 lordosis. The aged population, group I and group III, showed greater C3-C4 angulation associated with C4 forward inclination in neutral standing position as compared with younger patients. Regarding dynamic factors, group I showed the largest segmental motion at C3-C4, and, conversely, the smallest mobility at the lower segments, with significant differences. CONCLUSIONS: Using radiographic analysis, morphologic features that predispose patients to disorders of the C3-C4 motion segment were evaluated. These features included 1) greater C3-C4 angulation associated with age-related postural change and 2) hypermobility at the C3-C4 segment compensating for decreased mobility at the lower segments.  相似文献   
9.
Possible induction of lacZ mutation was examined in the liver and testis of Muta Mouse following the administration of carcinogenic halogenated compounds, namely 1,2-dichloroethane (DCE), 1,2-dibromoethane (DBE), carbon tetrachloride, or 1,2-dibromo-3-chloropropane (DBCP). Slight increases were observed on the mutant frequency in the testis DNA isolated from the mice 14 days after treatment with DBCP at 40 mg/kg or with DBE at 60 mg/kg but not in the liver. Further investigation was necessary to confirm the mutation induction by these chemicals in the testis including experiments with longer sampling intervals. No increase was detected in the frequency following DCE administration of single doses of up to 150 mg/kg or of consecutive injections of up to 280 mg/kg. Marginal but biologically insignificant responses were observed in the liver from the carbon tetrachloride exposed mice. The present results suggest that these carcinogenic chemicals are less efficient for induction of gene mutation in the liver of Muta Mouse.  相似文献   
10.
PURPOSE: Few reports address the use of fluid-attenuated inversion-recovery (FLAIR) images of the brain in the diagnosis of extraaxial lesions. Our purpose was to assess the value of FLAIR images, including postcontrast ones, in the diagnosis of intracranial meningeal diseases. METHODS: We reviewed precontrast (n=24) and postcontrast (n=20) FLAIR images obtained from 25 patients with infectious meningitis (n=13), carcinomatous meningitis or dissemination of primary brain tumor (n=7), dural metastasis (n=3), and others (n=2) in comparison with fast spin-echo T2-weighted and postcontrast T1-weighted images. RESULTS: In lesion detectability, precontrast FLAIR images were significantly superior to fast spin-echo T2-weighted images but inferior to postcontrast T1-weighted images. There was no significant difference between postcontrast T1-weighted and FLAIR images. CONCLUSION: Precontrast FLAIR images can substitute for conventional fast spin-echo T2-weighted images. Postcontrast FLAIR images have diagnostic potential equivalent to conventional postcontrast T1-weighted images.  相似文献   
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