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排序方式: 共有685条查询结果,搜索用时 734 毫秒
71.
YOW-CHERNG HORNG MEI-HWEI CHANG CHIN-YUN LEE A. SAFARY FRANCIS E. ANDRE DING-SHINN CHEN 《Journal of gastroenterology and hepatology》1993,8(4):338-341
The immunogenicity and adverse reaction of an inactivated hepatitis A (HA) vaccine were investigated. Sixty healthy adult volunteers who lacked antibody to HA virus (anti-HAV) received three doses of vaccine containing 720 enzyme-linked immunosorbent assay (ELISA) units (EL.U) according to a 0, 1 and 6 month schedule. Blood tests for serum liver enzymes and anti-HAV were performed at screening 7 days prior to, and 1, 6 and 7 months after the first dose. Anti-HAV was tested by radio immunoassay and ELISA for titre determination. The seroconversion rates measured by ELISA were 98.3% (59/60) at months 1 and 6 and 100% at month 7. Sixty-one per cent (109/180) of the documented injections were followed by local symptoms, essentially mild soreness at the site of injection; and 22.2% (40/180) by minor general symptoms including malaise, fatigue and lethargy. It is concluded that HA vaccine is highly immunogenic and safe. It may replace immunoglobulin as an effective method of preventing HA virus infection in adults. 相似文献
72.
Tytti Kärkkäinen 《Molecular immunology》1985,22(5):589-595
Human plasma kininogens were purified by immunoadsorption on Sepharose columns using two different approaches, either removing protein impurities with the respective immunospecific polymers or applying an anti-kininogen-specific immunoadsorbent column. An anti-kininogen serum developed and investigated in this laboratory in earlier studies was used. This antiserum recognizes the native conformational determinants in the kininogen heavy chain, the common denominator in plasma kininogens, and reacts with three heterogeneous molecular forms of high mol. wt kininogen (mol. wts 103,000, 92,000 and 90,000) as well as with low mol. wt kininogen. Heterogeneity of kininogens was shown by SDS gel electrophoresis and immunoelectrophoresis. With the antibody-specific polymers the yield was 80-100% compared to 75% or lower when several consecutive immunoadsorption steps were applied to remove impurities. Both methods serve the purpose of preparing immunologically pure kininogens suitable for immunization. 相似文献
73.
Two assays for the detection of antibody against hepatitis B surface antigen (anti-HBs) were compared. The first was a direct sandwich radioimmunoassay (RIA) which detects, in principle, antibody against any epitope of hepatitis B surface antigen (HBsAg). The second assay was an inhibition enzyme-linked immunosorbent assay (ELISA). In this assay a fixed amount of HBsAg which can be blocked by anti-HBs is measured in a direct sandwich test. Prevaccination screening sera (n = 191) and follow-up sera obtained from high risk groups (n1 = 85; n2 = 41) during two hepatitis B vaccine studies were compared in RIA and ELISA. In prevaccination sera either HBsAg or anti-HBs were detected by ELISA. Full agreement between the results of RIA and ELISA for anti-HBs was obtained in sera containing more than 10 IU/1 anti-HBs. Both tests showed variable results at low titres. Experiments with monoclonal anti-HBs indicated that ELISA is less sensitive for subtype specific antibodies (anti-d, anti-y), which may explain that there were consistent differences between RIA and ELISA in a minority of cases. 相似文献
74.
New bacterial absorption method for determination of hepatitis A IgM and IgA antibodies 总被引:1,自引:0,他引:1
Bengt Lfgren Erik Nordenfelt Svante Jonsson Gran Kronvall 《Journal of medical virology》1980,6(1):37-44
Antibodies against hepatitis A virus (anti-HAV) can be determined by a commercially available radioimmunoassay (RIA) (HavabTM, Abbott). To discriminate between recent and past hepatitis A infection this RIA was used in combination with absorption with protein A-containing staphylococci. However, nonabsorbable anti-HAV was repeatedly detected in late-convalescent sera using this methods. The nature of these antibodies was studied in serum samples from 12 such patients. In all patients, the late-convalescent sera contained no IgM class anti-HAV as judged by sucrose density gradient centrifugation. The restricted specificity of staphylococcal protein A explains the lack of absorption. Some recently described streptococcal strains capable of binding all IgG subclasses (including IgG3) as well as both IgA subclasses were, therefore, added to the staphylococci. Absorption studies using these strains indicated that the previously nonabsorbable anti-HAV in these 12 patients was mainly of the IgA class. A bacterial mixture including IgA-binding streptococci seems preferable to routine determination of IgM anti-HAV in acute hepatitis A diagnosis. The results also indicate that IgA anti-HAV in serum can persist for more than two years after a hepatitis A infection. 相似文献
75.
Sang S. Park Tadahiko Fujino Haruko Miller Frederick P. Guengerich Harry V. Gelboin 《Biochemical pharmacology》1984,33(13):2071-2081
Somatic cell hybrids were made between mouse myeloma cells and spleen cells derived from BALB/c female mice immunized with purified phenobarbital-induced rat liver cytochrome P-450 (PB-P-450). Hybridomas were selected in HAT medium, and the monoclonal antibodies (MAbs) produced were screened for binding to the PB-P-450 by radioimmunoassay, for immunoprecipitation of the PB-P-450, and for inhibition of PB-P-450-catalyzed enzyme activity. In two experiments, MAbs of the IgM and IgG1 were produced that bound and, in certain cases, precipitated PB-P-450. None of these MAbs, however, inhibited the PB-P-450-dependent aryl hydrocarbon hydroxylase (AHH) activity. In two other experiments, MAbs to PB-P-450 were produced that bound, precipitated and, in several cases, strongly or completely inhibited the AHH and 7-ethoxycoumarin deethylase (ECD) activities of PB-P-450. These MAbs showed no activity toward the purified 3-methylcholanthrene-induced cytochrome P-450 (MC-P-450), β-naphthoflavone-induced cytochrome P-450 (BNF-P-450) or pregnenolone 16-α-carbonitrile-induced cytochrome P-450 (PCN-P-450) in respect to RIA determined binding, immunoprecipitation, or inhibition of AHH activity. One of the monoclonal antibodies, MAb 2-66-3, inhibited the AHH activity of liver microsomes from PB-treated rats by 43% but did not inhibit the AHH activity of liver microsomes from control, BNF-, or MC-treated rats. The MAb 2-66-3 also inhibited ECD in microsomes from PB-treated rats by 22%. The MAb 2-66-3 showed high cross-reactivity for binding, immunoprecipitation and inhibition of enzyme activity of PB-induced cytochrome P-450 from rabbit liver (PB-P-450LM2). Two other MAbs, 4-7-1 and 4-29-5, completely inhibited the AHH of the purified PB-P-450. MAbs to different cytochromes P-450 will be of extraordinary usefulness for a variety of studies including phenotyping of individuals, species, and tissues and for the genetic analysis of P-450s as well as for the direct assay, purification, and structure determination of various cytochromes P-450. 相似文献
76.
77.
Inhibition of bovine platelet function by T-2 toxin, HT-2 toxin, diacetoxyscirpenol and deoxynivalenol 总被引:1,自引:0,他引:1
The aggregation of bovine platelets suspended in homologous plasma is inhibited in the presence of T-2 toxin, HT-2 toxin, diacetoxyscirpenol (DAS) or deoxynivalenol (DON) when either collagen or ADP is used as the stimulatory agent for aggregation. For each of the mycotoxins the degree of inhibition is dependent on the amount of trichothecene present in the platelet suspension but is not dependent on the time of exposure of the platelets to the toxin. For both ADP- and collagen-stimulated platelets, the order of potency of inhibition is T-2 toxin greater than HT-2 toxin greater than DAS greater than DON. A significant (P less than 0.01) dose-dependent decrease was also observed in the amount of the thromboxane B2 released from collagen-stimulated platelets in the presence of each of the mycotoxins. 相似文献
78.
Summary: The biological and immunological activities of luteinizing hormone (LH) and follicle stimulating hormone (FSH) in the serum of infertile males were determined by radioreceptor (RRA) and radioimmunoassay (RIA), respectively.
In some sera the biological activity of serum LH was lower than expected on the basis of the RIA-data. In contrast, some sera contained unusually high levels of biologically active LH as demonstrated by RRA, despite not being detected in these amounts by RIA.
Prolonged exposure of the gonad to such high levels of biologically active LH might cause end-organ desensitization resulting in infertility. The detection of such cases by the use of RRA could permit therapy in these individuals or exclude patients from treatment.
Zusammenfassung: Vergleich der biologischen und immunologischen Aktivitäten des luteinisierenden und des follikelstimulierenden Mormons aus dem Serum infertiler Männer
Die biologischen und immunologischen Aktivitäten des luteinisierenden Hormons (LH) und des follikelstimulierenden Hormons (FSH) im Serum infertiler Männer wurden durch Radiorezeptor-Assay (RRA) und Radioimmun-Assay (RIA) ermit-telt.
In einigen Seren mit relativ hohen immunologischen LH-Aktivitaten waren die biologischen LH-Aktivitäten niedriger als erwartet. Demgegenüber konnten bei einigen Proben überdurchschnittlich hohe Werte für biologisch aktives LH nachgewiesen werden, obwohl diese Seren bei RIA normale LH-Werte aufwiesen.
Eine andauernde Exposition der Gonaden solch hoher Mengen an biologisch aktivem LH, die durch RIA nicht aufgedeckt werden, kdnnte eine Gonaden-Insensitivität gegenüber diesem Hormon und damit Infertilität verursachen. Die Erfassung solcher Fälle mittels Radiorezeptor-Assay könnte die Therapie dieser Individuen ermöglichen bzw. sie von der Therapie ausschließen. 相似文献
In some sera the biological activity of serum LH was lower than expected on the basis of the RIA-data. In contrast, some sera contained unusually high levels of biologically active LH as demonstrated by RRA, despite not being detected in these amounts by RIA.
Prolonged exposure of the gonad to such high levels of biologically active LH might cause end-organ desensitization resulting in infertility. The detection of such cases by the use of RRA could permit therapy in these individuals or exclude patients from treatment.
Zusammenfassung: Vergleich der biologischen und immunologischen Aktivitäten des luteinisierenden und des follikelstimulierenden Mormons aus dem Serum infertiler Männer
Die biologischen und immunologischen Aktivitäten des luteinisierenden Hormons (LH) und des follikelstimulierenden Hormons (FSH) im Serum infertiler Männer wurden durch Radiorezeptor-Assay (RRA) und Radioimmun-Assay (RIA) ermit-telt.
In einigen Seren mit relativ hohen immunologischen LH-Aktivitaten waren die biologischen LH-Aktivitäten niedriger als erwartet. Demgegenüber konnten bei einigen Proben überdurchschnittlich hohe Werte für biologisch aktives LH nachgewiesen werden, obwohl diese Seren bei RIA normale LH-Werte aufwiesen.
Eine andauernde Exposition der Gonaden solch hoher Mengen an biologisch aktivem LH, die durch RIA nicht aufgedeckt werden, kdnnte eine Gonaden-Insensitivität gegenüber diesem Hormon und damit Infertilität verursachen. Die Erfassung solcher Fälle mittels Radiorezeptor-Assay könnte die Therapie dieser Individuen ermöglichen bzw. sie von der Therapie ausschließen. 相似文献
79.
A double-determinant sandwich radioimmunoassay (RIA) is described for the specific detection of anti-I-Ak monoclonal antibody (mAb) in the sera of non-Ighb murine hosts undergoing anti-Ia immunotherapy. This RIA utilizes 2 previously undescribed mAb reagents generated against an Ia.17-specific mAb secreted by the 10-3.6 hybridoma. The first reagent, 7.34, is specific for Ighb-linked allotypic determinants on the Fc portion of IgG2a immunoglobulins as defined by the pattern of reactivity with normal sera from a panel of inbred and Igh recombinant inbred strains. The second reagent, 58.3, is an anti-idiotypic mAb recognizing unique determinants in the combining site of 10-3.6 immunoglobulins, as determined by the specificity of the 58.3 mAb in solid-phase RIA and the capacity of this reagent to inhibit the binding of labeled 10-3.6 mAb to I-Ak-expressing spleen cells. In an RIA procedure using purified 58.3 mAb as substrate and 125I-labeled 7.34 as the detection reagent, serum concentrations of 10-3.6 as low as 1-5 ng/ml can be measured reproducibly after mathematical linearization of the sigmoid standard curve. In the present studies, the serum half-life of 10-3.6 mAb was calculated from assay data to be 3-5 h in I-Ak homo- or heterozygotes and 72 h in non-I-Ak mice. The serum level of 10-3.6 as a function of the mAb treatment protocol was also examined and results are considered with respect to the efficacy of different therapeutic regimens in prolonging transplant survival. Sandwich immunoassays of this type (RIA or ELISA) should provide a highly sensitive and specific means for monitoring serum mAb levels in individuals subjected to antibody immunotherapy for treatment of autoimmune disease, transplant rejection or tumor progression. 相似文献
80.
Jerrold S. Meyer 《Experimental neurology》1983,82(2):432-446
Rats were adrenalectomized (ADX) or sham-operated (SHAM) on the 11th day of life and subsequent brain development (cerebrum and cerebellum) studied in terms of tissue weight and biochemical composition. Measured at about 65 days of age, early ADX subjects had significantly heavier brains (in terms of both wet and dry weights) than SHAMs, despite being lighter in overall body weight. Brain protein and DNA contents were elevated, as was the activity of 2′,3′-cyclic nucleotide 3′-phosphodiesterase (CNP), a myelin marker enzyme. Glycerol-3-phosphate dehydrogenase (GPDH), a glucocorticoid-regulated enzyme, was reduced in activity. Although both the cerebrum and cerebellum showed the growth-enhancing effects of early adrenalectomy, the DNA and CNP changes were most pronounced in the cerebrum. Finally, the effect of adrenal removal on myelinogenesis was confirmed by subcellular fractionation experiments demonstrating that more myelin could be recovered from the brains of ADX than from SHAM animals. These results are significant in terms of the influence of adrenal secretions on normal brain development and the role of GPDH in myelin lipid biosynthesis. 相似文献