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51.
A series of T-cell-specific monoclonal antibodies (Leu-1, Leu-2a, and Leu-3a) and B-cell-specific monoclonal antibody (HLB-1) were used to detect the localization and intensity of infiltration of lymphocyte subpopulations and T-cell subsets in frozen sections of 17 patients with the oral cancer. The vast majority of the lymphocyte infiltrates in the oral cancer tissues were reactive with Leu-1. In contrast, B cells were detectable with HLB-1 in only 2 of 17 cases. Leu-2a-positive cells were dominant in four cases, whereas Leu-3a positive cells were dominant in only three cases. In seven cases, both cells infiltrated to the same degree. Leu-2a positive cells tended to be dominant in the cases with earlier clinical stages.  相似文献   
52.
The supernatant from cultures of T cell clones derived from (BALB/c----C3H/He) chimeras suppresses BALB/c anti-C3H/He or BALB/c anti-C57BL/6 MLRs. When we studied the alloantigen specificity of the suppressor activity in culture supernatant, we observed three types of the suppressor activity (i.e., the suppressor activity against BALB/c anti-C3H/He MLR, against BALB/c anti-C57BL/6 MLR, and against both MLRs) on day 3 after stimulation of the T cell clones with 20% crude IL2 and feeder cells. Since the alloantigen specificity fluctuated somewhat with time, we considered that a time-course study was needed to determine it correctly. We thought it unlikely that any IFN-gamma or PGE2 in the culture supernatant of the T cell clones would have mediated the suppression. Our results suggest that alloantigen specific and non-specific suppressor T cells exist in bone marrow chimeras. The former appears to play an important role in inducing and maintaining transplantation tolerance, while the latter seems to have a rather harmful effect upon chimeras.  相似文献   
53.
Restoration of T-cell functions and changes in autoantibody production were studied in BALB/c nu/nu (nude) mice engrafted with syngeneic (BALB/c) or allogeneic (C57BL/6J) thymuses across major histocompatability barriers. T-cell functions, including mitogen responses and antibody production to sheep red blood cells (SRBC), were restored in nude mice engrafted with either allogeneic or syngeneic thymuses. Alloreactivity was evaluated by analysis of the pattern of skin allograft rejection, generation of alloreactive cytotoxic T-lymphocytes (CTLs), or quantitation of mixed-lymphocyte reaction (MLR). BABL/c nude mice engrafted with thymuses from newborn C57BL/6J mice accepted the skin from either thymus donor-type mice or from host-type mice. By contrast, such thymic chimeras rejected skin grafts from a third-party donor. CTLs from nude mice engrafted with C57BL/6J thymuses were cytotoxic to target cells of the third party but not to target cells of the host-type or of the thymus-type. In the MLR assay, spleen cells of nude mice engrafted with C57BL/6J thymuses responded vigorously to third party cells and only slightly to cells of the thymus-type. Low levels of serum IgG and high titers of IgM antibodies to nuclear antigens (but not dsDNA) or skin basal cells were also found in nude mice. Antibodies to both nuclear antigens and skin basal cells disappeared after transplantation of syngeneic thymuses, but not after transplantation of allogeneic thymuses. By contrast, serum IgG levels were restored to normal in nude mice engrafted with either syngeneic or allogeneic thymuses. These results suggest that either HLA-matched or HLA-mismatched thymus grafts may become a viable treatment for certain patients with T cell deficiencies associated with deficient development or maintenance of thymic structure and/or function.  相似文献   
54.
55.
Spleen cells from C3HfB/HeN mice (H-2kv1) were markedly less susceptible to lysis by monoclonal anti-Kk antibody (Clone 11-4) than spleen cells from C3H/HeN mice (H-2k). Less than 50% of C3HfB/HeN cells were lysed even at the highest antibody concentration tested compared to 70% of C3H/HeN cells. The difference in end point titre of the antibody tested on cells from the two strains was 5-10-fold. Similar differences were not observed using the conventional H-2Kk-typing antiserum (D-23).  相似文献   
56.
Due to increasing national health expenditure and an aging society, Japan in the 1980s started to reinforce home health care, going beyond her long-time investment in institutional care. Since 1983, a sequence of policies was issued focused mainly on frail elderly care. In support of this governmental approach, a variety of enterprises and charity activities have flourished. Now, however, in the midst of a worldwide recession, rationing as health policy is under reconsideration and has an influence on health care for minorities, including the elderly. In Japan, home health care is under review and a new service system was initiated in April 1992. In this article, the newly inaugurated community-based home visiting nursing scheme is introduced together with a short history of elderly care and related business activities in Japan. Feasibility of the new scheme is discussed and compared with the previous version of home visiting nursing, which had its base in hospitals.  相似文献   
57.
We have developed a new type of drug delivery system (DDS) comprising a complex of porous hydroxyapatite (HAP) with the anticancer drug doxorubicin hydrochloride (DOX) and the glutathione inhibitor buthionine sulfoximine (BSO) (DOX and BSO-HAP complex). We then studied the antitumour effect of DOX and BSO-HAP combined with 44 degrees C hyperthermia for 40 min. It was found that in mice this combined treatment suppressed the growth of sarcoma 180 in terms of tumour volume to 36% in comparison viith mice given plain HAP, and was more effective than HAP + hyperthermia or DOX- and BSO-HAP. These results were also confirmed by histological observation.  相似文献   
58.
Although a fistula is a rare complication of ovarian tumor, we encountered four patients with cole-ovarian fistulas in three years. The first case was demonstrated by following barium enema by the extravasation of barium from the sigmoid colon, and by a gas-containing lesion in the tumor observed on computed tomography. Mature cystic teratoma was the pathological diagnosis in two cases. A mixed germ cell tumor and a serous cystadenoma of low malignant potential were diagnosed in the other two cases. The etiology and differential diagnosis of cole-ovarian fistula are reviewed.  相似文献   
59.
60.
We examined different fluorescent probes suitable for fluorometric determination of 1-acid glycoprotein (AGP) in serum. Quinaldine red (QR) was shown to bind strongly and selectively to AGP. Taking advantage of the enhanced fluorescence of QR in the presence of AGP, we developed a direct method for the determination of serum AGP without removal of other serum proteins such as albumin. AGP concentrations in serum of healthy volunteers and patients correlated well with results from the conventional single radial immunodiffusion (SRID) method (r = 0.93, slope = 1). The newly developed method is faster and has a larger analytical concentration range than the SRID method. This method can also be used to determine AGP in serum of experimental animals, and it can serve to monitor AGP serum concentrations for pharmacokinetic evaluation of basic drugs.  相似文献   
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