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11.
Functional and immunogenetic characterization of FcR-blocking antibody   总被引:1,自引:0,他引:1  
The characteristics and functional importance of FcR-blocking antibodies and their production were investigated after immunization with whole blood, "buffy coat" and purified platelets. We studied the presence of FcR-blocking antibody in haemodialyzed, transfused patients waiting for kidney transplantation, and we found strong correlation between the blocking effect and better graft survival. We suggest that this blocking antibody does not attack FcR as primary target. Investigation of blocking activity of ten different immune sera on 50 healthy panel cells showed that target antigen has some polymorphic varieties. On basis of family studies it seems that the target antigen is not linked to HLA haplotype. The blocking effect of sera could be removed by absorption of CD8+ cells, B lymphocytes, platelets and granulocytes, but not with erythrocytes, monocytes, CD8- cells and NK cells.  相似文献   
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Summary The ability of lymphocytes from patients with multiple sclerosis (MS) to produce Interferon (IFN-) in response to Newcastle Disease Virus (NDV) was studiedin vitro. The correlation between individual IFN- titers and natural killer (NK) cell activity and the presence of HLA system antigens associated with MS (B-7 and DRW-2) was also investigated.Lymphocytes from MS patients showed a significantly impaired capacity to synthesize IFN-in vitro when compared to lymphocytes from healthy donors (mean titers: 85.9 I.U. and 268.2 I.U., respectively). Marked differences in IFN- titers were observed in the group of MS patients.The production of IFN- by the patients' lymphocytes did not correlate with either the activity of NK cells or with their stimulation by exogenous IFN-. There was also no correlation between IFN- production by lymphocytes from MS patients and the presence or absence of B-7 and DRW-2 antigens.With 3 Figures  相似文献   
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Neurosurgical Review - To assess automated volumetric analysis as a potential presurgical diagnostic tool or as a method to potentially shed light on normal pressure hydrocephalus (NPH)...  相似文献   
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BackgroundWilms tumor (WT) affects Black children disproportionately. Genetic aberrations within WT specimens that contribute to this disparity have not been reported.MethodsThe Therapeutically Applied Research to Generate Effective Treatments (TARGET) database was queried for WT patient and genomic features. Clinical and genetic variables were compared by race.ResultsWithin the discovery set (enriched for adverse events; N = 94 White, 19 Black, 14 Other/unreported patients), Black children were more likely to present with advanced stage disease (p = 0.019). Within the validation set (primarily a random sampling of NWTS-5; N = 360 White, 92 Black, 72 Other/Unreported), Black children appeared older at diagnosis (p = 0.050), had decreased median follow-up time (p<0.0005) and were over-represented (17.4%) relative to the concurrent U.S. Census (12.8%). Among the 37 target genes sequenced, ACTB (p = 0.030) and DICER1 (p = 0.026) mutations were more common in Black patient specimens, whereas DGCR8 (p = 0.041) mutations were more common in White patient specimens. White patient specimens were more likely to contain one or multiple targeted mutations (p = 0.026).ConclusionWithin the TARGET database, Black children were over-represented and harbored WT specimens containing more frequent ACTB and DICER1 mutations. In contrast, WT from White children contained overall more mutations in targeted genes and specifically in DGCR8.Level of EvidenceIII.  相似文献   
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Summary The molecular mechanism(s) underlying the vasodilator activity of CAS 936 (3-(cis-2,6-dimethylpiperidino)-N-(4-methoxybenzoyl)-sydnonimine) and its metabolites 3-(cis-2,6-dimethylpiperidino)-sydnonimine (C87 3754) and N-(cis-2,6-dimethylpiperidino)-N-nitroso-2-aminoacetonitril (C873786) was investigated. These compounds were tested for their relaxant activity in isolated rabbit arterial segments, activation of purified soluble guanylyl cyclase and release of nitric oxide (NO) in vitro and in vivo. C873754 and C873786 inhibited the noradrenalin-induced contraction and increased the cyclic GMP content of endothelium-denuded rabbit aortic and femoral segments, whereas CAS 936 was without effect. Similarly, both metabolites, but not CAS 936, activated purified soluble guanylyl cyclase (EC50 about 30 M) and released NO in buffered aqueous solutions, as detected by electron spin resonance (esr) spectrometry. Both in vitro and in vivo an accumulation of NO was detected by esr spectrometry in vascular tissues exposed to the metabolites of CAS 936, whereas a significant release of NO from CAS 936 was only detected in the isolated rabbit liver, but not in vascular tissue. It is conceivable, therefore, that the metabolites of CAS 936 appearing in the systemic circulation after hepatic biotransformation induce vasodilatation by release of NO and activation of soluble guanylyl cyclase in vascular smooth muscle. Moreover, the activation of soluble guanylyl cyclase in vitro by the metabolites of CAS 936 was significantly enhanced by co-incubation with certain particulate fractions from bovine aortic endothelial and smooth muscle cells. Thus, an enzymic release of NO from these metabolites in addition to their spontaneous decomposition may play a significant role for their vasodilator activity in vivo.Correspondence to A. Mülsch at the above address  相似文献   
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Background: The highly swelling poly(glycerol monomethacrylate) gel (polyGLYMA) and hydrophilic polymer poly(triethylenglycol monomethacrylate (polyTEGMA) were tested as potential viscoelastics for intraopertive use in anterior segment surgery. Methods: PolyGLYMA was implanted into the anterior chamber in 5 rabbits, and 40% polyTEGMA in 16 rabbits. The eyes were enucleated 1 week to 3 months after the operation. The corneal endothelium was examined with specular microscopy, and then the whole eye histopathologically. Results: In all eyes of the polyGLYMA group, the clinical findings were characterized by a marked ciliary injection and severe secondary glaucoma, and the histologic ones by a marked inflammatory infiltration and thickening of Descemet's membrane in the anterior chamber angle. Specular microscopy revealed a decrease in the endothelial cell density and polymorphism of the endothelial cells. In the polyTEGMA group, the anterior segment and the fundus were physiologic all the time, and specular microscopy and histologic findings showed no degenerative and/or inflammatory changes. Conclusions: PolyGLYMA proved unsuitable for intracameral application in rabbits. The new polymer polyTEGMA is characterized by high biologic tolerance after its implantation into the anterior chamber of rabbits. PolyTEGMA 40% might be considered as a potential viscoelastic material in humans.  相似文献   
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Some pathological findings and prognostic indices recorded in breast cancer cases, detected, on one hand, by a provider-initiated mammography screening program (Group 1), and, opportunistically, in self-referred symptomatic women (Group 2) on the other, are compared. In 8877 symptom-free women, aged 50-65 years, individually invited to attend the screening offered for the residents of the III., XII. and XIII. districts of Budapest, 67 cancer cases were detected (7.5 in 1000 screenees), in accordance with the cancer detection rate of the first, "prevalence" round of organised screening programmes. In the other group of 1593 symptomatic, self-referred women of the same age, 113 cancer cases were diagnosed by mammography. As far as the pathological parameters are concerned, the number of cases with invasive cancer less than 15 mm in diameter, and those with axillary nodes present was found to be significantly higher in the screened group as compared to the self-referred one (p < 0.01). In "small" cancers (i.e. less than 15 mm in diameter), no significant difference was found in the proportion of histologic grade III tumours among the two groups. In screen-detected cancers both the morphometric prognostic index (as calculated by Baak et al.) and the Nottingham Prognostic Index (NPI) proved to be more favourable, as compared to those in the self-referred group. The p-value as determined by Mann-Whithey test was 0.000003 in the screened group, and 0.000015 in the other one. These findings provide convincing evidence in support of the public health importance of provider-initiated, organised mammography screening for breast cancer, therefore, the introduction on service basis of organised breast screening into the health care system in Hungary is strongly recommended by the authors.  相似文献   
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