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81.
We have investigated quantitatively the complement-mediated binding of prepared, soluble 125I-7S IgG antibody/3H-dsDNA immune complexes to human red blood cells (RBCs). We have performed these studies by using a detailed modification of the RBC-CF assay [Pedersen et al., J. Immun. Meth. 38, 2692–2280 (1980)] which now allows for the simultaneous measurement of both 3H-DNA and 125I-binding to the cells. Our results indicate that, in the case of three SLE patients, their anti-dsDNA antibody titers are sufficiently high that a small fraction of their 125I-7S IgG antibodies (ca 0.1–0.2%) can be identified as specifically anti-dsDNA. We have also used an indirect method (with 125I-labelled rabbit anti-human IgG) for the determination of IgG anti-dsDNA antibodies in complement-fixing antibody/dsDNA immune complexes that bind to RBCs, and the results of these measurements are in reasonable agreement with the direct binding experiments. These studies have also allowed us to estimate the antibody/DNA stoichiometries in complement-fixing immune complexes. The results of these experiments may provide a useful standard for the analysis of monoclonal anti-dsDNA antibodies. 相似文献
82.
茶色素治疗糖尿病前后血液流变性和微循环检测分析 总被引:1,自引:0,他引:1
目的:观察茶色素治疗糖尿病前后血液流变微循环的变化。方法:糖尿病人88例,男71例,女17例,年龄32~64岁。口服茶色素2粒(250mg),每日3次,疗程为30天。结果:血液流变学参数、微循环积分值、血生化指标、RIA都有明显改善(P<0.01或P<0.05)。结论:茶色素可以明显改善糖尿病人血液流变性和微循环多项检测指标,值得临床推广应用。 相似文献
83.
The effect of different doses of sheep's red blood cells (SRBC) on endogenous colony formation and immunogenesis was studied in CBA and C57BL mice. The absolute and relative numbers of antibody-forming cells (AFC) was shown to increase with an increase in the dose of SRBC from 2×107 to 2×108, and to decrease with a dose of 2×109 in mice of both lines. With an increase in the dose of antigen, the number of endogenous splenic colonies (ESC) of hematopoietic cells also increased. Interlinear differences in the number of ESC persisted. It is suggested that the mechanism of stimulation of the hematopoietic series is based on a unique type of blockade of the reticuloendothelial system by foreign red blood cells, leading to increased proliferative activity of the stem cells.Laboratory of Regulation of Immunopoiesis, Institute of Clinical and Experimental Medicien, Siberian Branch, Academy of Medical Sciences of the USSR, Novosibirsk. (Presented by Academician of the Academy of Medical Sciences of the USSR V. P. Kaznacheev.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 87, No. 4, pp. 330–332, April, 1979. 相似文献
84.
Paloma E Coco R Martínez-Mir A Vilageliu L Balcells S Gonzàlez-Duarte R 《Human mutation》2002,20(6):476-476
Genotype-phenotype correlations highlighted the function of ABCA4 in retinitis pigmentosa (RP),cone-rod dystrophy (CRD) and Stargardt/Fundus Flavimaculatus disease (STGD/FFM). Initial screening of ABCA4 variants showed a correlation between the type of mutation and the severity of the disease. In the present study we have undertaken mutational and haplotype analysis of ABCA4 in three mixed pedigrees segregating different retinal dystrophies. In family I, we have shown cosegregation of different ABCA4 alleles with CRD (homozygosity for L1940P) and three subtypes of STGD/FFM. The first, a mild form, consisting on fundus flavimaculatus-like distribution of flecks, but good visual acuity and absence of dark choroid, was found to cosegregate with alleles R1097C and F553L; the second, a conventional Stargardt phenotype was associated to alleles L1940P/R1097C and the third, displaying severely reduced visual acuity and dark choroid (named FFM), was associated to L1940P/F553L. In family II, segregating STGD and RP phenotypes, while the involvement of ABCA4 in STGD seems clear this is not the case for RP. Finally, in family III, also segregating STGD and RP, ABCA4 fails to explain either phenotype. Our data highlight the wide allelic heterogeneity involving this gene and support the genetic variability (beyond ABCA4) of mixed STGD/RP pedigrees. 相似文献
85.
An autoradiographic method combined with a rosette technique was used to assess the bactericidal activity of individual control and inflammatory peritoneal macrophages (PM phi) in the presence or absence of expression of Fc receptor for IgG (FcR). There was a lack of FcR reactivity in a certain percentage of both categories of PM phi exposed to E. coli X43, a bacterium which is readily phagocytosed in the presence of specific antibody. Both rosetting and non-rosetting PM phi were capable of phagocytosing E. coli X43, but inflammatory PM phi showed a marked reduction in their capacity to ingest these bacteria compared with control PM phi. Once ingested the E. coli X43 were killed equally well by non-rosetting and rosetting control and inflammatory PM phi. 相似文献
86.
C. MONTEAGUDO E. JORDÁ C. CARDA C. ILLUECA A. PEYDRÓ & A. LLOMBART-BOSCH 《Histopathology》1997,31(4):367-373
Aims:
Erythrophagocytosis is a characteristic feature of tumour cells in malignant histiocytosis, some leukaemias, lymphomas, and also reactive histiocytes in the haemophagocytic syndrome associated with a variety of infections and neoplasms. It has also been found exceptionally in metastatic malignant epithelial cells in bone marrow and lymph nodes. We present two cases, a cutaneous malignant melanoma and an acantholytic squamous cell carcinoma, in which erythrophagocytosis by tumour cells was demonstrable by both light and electron microscopy.
Methods and results:
The melanocytic and squamous nature of these cells was supported by the immunohistochemical detection of HMB45, S100, and NKI-C3 in the former, and cytokeratin and EMA in the latter, and at ultrastructural level by the presence of melanosomes and tonofilaments, respectively.
Conclusions:
This is, to our knowledge, the first documented report of erythrophagocytic tumour cells in human melanomas and primary carcinomas. Biological considerations apart, this unusual feature can prove to be of value to avoid a misdiagnosis of a variety of haematopoietic malignancies. 相似文献
87.
根据红细胞聚集时,可减少血样光散射表面的数目和光通过血样透射强度增加的原理,设计了一种新型的双圆筒式的红细胞聚集仪。该仪器具有测量速度快、测量精度高和重复性好等优点。它的产生,将为实验室和临床进行红细胞聚集的研究及检测,提供方便和可靠的测量。 相似文献
88.
Nils Koppang 《American journal of medical genetics. Part A》1992,42(4):599-604
The etiology of the juvenile type of the human ceroid-lipofuscinosis (JCL) is unknown, in spite of the fact that the first report of this disease was given more than 160 years ago. The necessity of good animal models for scientific progress in chronic metabolic diseases in humans is obvious. The inbred strain of English setter with ceroid-lipofuscinosis (CCL) seems to be a perfect model for human JCL. Dogs with CCL and organs for research purposes are available from Dr. Koppang's experimental kennel in Norway. 相似文献
89.
L. Hübner E.M. Kniep H. Laukel C. Sorg H. Fischer W.D. Gassel K. Havemann B. Kickhöfen M.-L. Lohmann-Matthes A. Schimpl E. Wecker 《Immunobiology》1980,157(2):169-178
Supernatants from Concanavalin A-stimulated murine spleen cells were subjected to hydrophobic interaction chromatography on phenyl-Sepharose. Macrophage cytotoxicity factor (MCF), macrophage migration inhibitory factor (MIF), T-helper cell-replacing factor (TRF) and colony-stimulating factor (CSF) were bound at high ionic strength and were released stepwise at low ionic strength. CSF thus could be separated from MCF, MIF and TRF and the bulk of other proteins. Chromatography of pools containing MCF, MIF and TRF on Sephadex did not lead to a separation of the three activities which were all found in a molecular weight range of 25.000-55.000. Isoelectric focusing of these pools in pH range from 4 to 9 gave two peaks for MCF at pH 8.2 and 7.2, whereas MIF activity focused from pH 4.5 to 5.5. TRF activity was found in a single sharp peak at pH 5.3. The results demonstrate that the four biological activities can be distinguished on a chemical basis and are accessible for purification and chemical characterization. 相似文献
90.
G. García-Ugalde R. Tapia 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1991,86(3):633-640
Summary In this work we have studied in the rat the behavioral effects of the intraperitoneal (i.p.) and intrahippocampal (i.h.) administration of ruthenium red (RuR), an inorganic dye which has been shown to inhibit neurotransmitter release in synaptosomes. The i.p. injection induced initially flaccid paralysis and subsequently generalized tonic-clonic convulsions. It contrast, unilateral RuR microinjection into the CA1 area of the hippocampus produced complex seizure behavior and wet-dog shakes (WDS). The i.p. administration of the serotonin receptor antagonist ketanserin markedly inhibited the WDS induced by i.h. RuR. In contrast, the i.h. injection of ketanserin and of the -aminobutyric acid (GABA) agonists 4,5,6,7-tetrahydroisoxazol[5,4-c]pyridin-3-ol (THIP) and baclofen together with RuR did not affect the frequency of WDS nor the seizure behavior. However, the i.h. injection of the GABA uptake blocker nipecotic acid, simultaneously with RuR, increased the frequency of WDS. The release of [3H]GABA, measured in synaptosomes of different cerebral structures of the rats injected i.p. with RuR, and in slices of the CA1 area after i.h. injection of the dye, was not affected. Histological observations of the injected area showed a specific and intense staining of the somas of the CA1 pyramidal neurons. It is concluded that the convulsant action induced by i.h. RuR microinjection is probably the result of an increased excitability of these CA1 neurons, which is independent of any action on GABA release. 相似文献