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51.
Key words  intractable pain - celiac plexus neurolysis - ultrasonography  相似文献   
52.
Radionuclides or anti-cancer drugs may be coupled to antibodies for specific transport to target tissues. We have previously reported that several proteins could be rapidly and efficiently labeled with gallium (67Ga) by using deferoxamine (DFO) as a bifunctional chelating agent. In the present paper, we have described the use of hetero-bifunctional agents for the conjugation of DFO with antibodies and investigated the effect of coupling agents on in vitro properties and biodistribution of 67Ga-labeled antibodies. 67Ga-labeled monoclonal antibodies retained antigen-binding activity when prepared under optimum conditions. The use of hetero-bifunctional reagents, such as succinimidyl 6-maleimido-hexanoate (EMCS) or N-succinimidyl-3-(2-pyridyldithio)-propionate (SPDP), which link thioether bonds and disulfide bridges prevented the formation of polymerized antibodies. Although high non-specific uptake in the liver was observed with radiolabels prepared by the homo-bifunctional agent glutaraldehyde, uptake in the liver was low with conjugates linked by hetero-bifunctional agents. 67Ga-labeled antibodies with thioether bonds showed in vivo stability, but the clearance from the circulation was the fastest with the radiolabel holding disulfide bonds. The coupling reagents used to link DFO and antibodies greatly influenced both in vitro properties and in vivo distribution of labeled antibodies and 67Ga-labeled antibodies provide a good model for the study of coupling methods and biodistribution of antibody conjugates.  相似文献   
53.
Peripheral blood samples from 52 women including 16 with herpes genitalis and 36 healthy persons were studied to enumerate subpopulations of lymphocytes. T lymphocyte counts were done by SRBC rosette tests and B lymphocytes by immunobead rosette tests using antibody-coated polyacrylamide beads. It was found that the mean percentage of «active T lymphocytes was significantly less in the patients with herpes genitalis than in the controls (herpes genitalis; 13.9 ± 6.8%, controls; 25.0 ± 8.3%, p < 0.001). No difference was noted in the percentage of «total» T lymphocytes, «total» B lymphocytes and subsets of B lymphocytes (IgG-, IgA- and IgM-bearing lymphocytes) between the patients and controls. The present findings suggest that cell-mediated immune function associated with «active» T lymphocytes is suppressed in patients with herpes genitalis.  相似文献   
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The cellular localization of Babesia bovis rhoptry-associated protein 1 (RAP-1) and its erythrocyte-binding affinity were examined with anti-RAP-1 antibodies. In an indirect immunofluorescent antibody test, RAP-1 was detectable in all developmental stages of merozoites and in extracellular merozoites. In the early stage of merozoite development, RAP-1 appears as a dense accumulation, which later thins out and blankets the host cell cytoplasm, but retains a denser mass around newly formed parasite nuclei. The preferential accumulations of RAP-1 on the inner surface of a host cell membrane and bordering the parasite's outer surface were demonstrable by immunoelectron microscopy. An erythrocyte-binding assay with the lysate of merozoites demonstrated RAP-1 binding to both bovine and equine erythrocytes. Anti-RAP-1 monoclonal antibody 1C1 prevented the interaction of RAP-1 with bovine erythrocytes and significantly inhibited parasite proliferation in vitro. With the recombinant RAP-1, the addition of increasing concentrations of Ca(2+) accentuated its binding affinity with bovine erythrocytes. The present findings lend support to an earlier proposition of an erythrocytic binding role for RAP-1 expressed in B. bovis merozoites and, possibly, its involvement in the escape of newly formed merozoites from host cells.  相似文献   
56.
Male Sprague-Dawley rats were fed for 4-5 weeks a choline-devoid diet containing 0.1% DL-ethionine. Preparations of nonparenchymal epithelial cells, enriched in oval cells, were isolated from the livers of these animals and were placed in culture. Six lines of hepatic epithelial cells were thus established. The lines underwent transformation after several passages, became tumorigenic in nude mice and 3 lines also in rats of the same strain of origin of the isolated cells. The tumors were uniformly highly anaplastic carcinomas. Preliminary morphologic, cytologic, and cytochemical results were consistent with the tumoral cells being hepatocytelike cells. These findings are viewed and discussed in terms of the cellular source, in vivo, of longterm cultures of rat liver epithelial cells, and in relation to a possible role of hepatic nonparenchymal epithelial cells in the process of hepatocellular tumor induction by chemical carcinogens.  相似文献   
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ALG raised against lymphoblasts grown in pure culture for many generations contained antiplatelet activity. The thromboagglutinins could be completely removed by absorption with lymphoblasts, indicating that they had been raised to antigens shared by lymphoblasts and platelets. Anti-spleen ALG possessed levels of such anti-platelet antibodies but in substantially higher titres, because an additional contribution was made by contaminating thrombocytes in the immunizing injectate. By chromatographic separation and immunoelectrophoretic analysis of the eluate from platelet–antibody complexes generated during the absorption of anti-spleen ALG with thrombocytes, the thromboagglutinins were shown to reside almost exclusively (97·7%) in the area of the IgA fraction. The direct Coombs' test, reacting platelets from patients receiving equine anti-spleen ALG with guinea-pig antisera against normal horse serum, showed a highly significant, but not invariable correlation with clinical platelet depression, which was not, however, clearly related to the thromboagglutinin titre of the ALG being administered.  相似文献   
59.
60.
Babesia microti, a hemoprotozoan parasite of rodents, is also important as a zoonotic agent of human babesiosis. The Maltese cross form, which consists of four masses in an erythrocyte, is characteristic of the developmental stage of B. microti. Monoclonal antibody (MAb) 2-1E, which specifically recognizes the Maltese cross form of B. microti, has been described previously. In the present study, we examined the roles of the Maltese cross form during the infectious course of B. microti in mice. The number of the Maltese cross form increased in the peripheral blood of infected mice prior to the peak of parasitemia. With confocal laser scanning microscopy, MAb 2-1E was found to be reactive with the ring form, with the parasites undergoing transformation to the Maltese cross form and subsequent division, and also with extracellular merozoites. Furthermore, the Maltese cross form-related antigen (MRA) gene was isolated from a B. microti cDNA library by immunoscreening with MAb 2-1E, and the nucleotide sequence was determined. Genomic analyses indicated that the MRA gene exists as a single-copy gene in B. microti. Immunization of mice with recombinant MRA induced significant protective immunity against B. microti infection. These findings indicate that the Maltese cross form plays important roles in both the development of parasitemia and the protective response against the infection.  相似文献   
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