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21.
Limited vertical skin incision for median sternotomy.   总被引:4,自引:0,他引:4  
The cosmetic deformity of the vertical skin incision for median sternotomy was decreased by using a mechanical traction system to increase exposure at the superior margin of a shorter wound. The limited vertical skin incision did not impede technical surgical maneuvers and produced a scar that was more acceptable than submammary incision or right anterior thoracotomy. The limited skin incision is especially useful in young women with congenital heart disease.  相似文献   
22.
Histopathologic changes in lymph nodes were examined from ten patients with mild lymphadenopathy, a few atypical lymphocytes in their peripheral blood, skin lesions, and proviral DNA of human T-cell leukemia virus type I (HTLV-I) in their nodes. The proviral DNA of HTLV-I was detected by southern blot analysis, in situ hybridization, and/or polymerase chain reaction techniques. The lymph nodes showed preserved nodal architecture with diffuse infiltration of small to intermediate-sized lymphocytes in association with scattered transformed lymphocytes and a few immunoblast-like cells in the enlarged paracortex. The infiltrating lymphocytes were positive for CD4, but neither rearrangement nor deletion of T-cell receptors and immunoglobulin heavy chain genes was detected. Eight of ten patients received no therapy, and all patients were alive and healthy more than 5 months after the biopsies. The histologic findings resembled those of a viral infection and could be distinguished from HTLV-I associated lymphomas.  相似文献   
23.
Complete porcine CD3ζ-chain cDNA sequence was obtained for the first time, and its genomic nucleotide sequence was investigated from exon 2 down to CD3η-chain exon 8. The sequence of porcine CD3ζ-chain showed homologous amino acid sequence with human and murine counterparts, in contrast to CD3η-chain exon 8 with diversity among animals previously investigated. CD3η-chain peptide is an alternative splice form of CD3ζ-chain exon 7 splicing to CD3η-chain exon 8 instead of CD3ζ-chain exon 8. The genomic sequences revealed that the splice acceptor sequences of CD3η-chain exon 8 of all animals investigated to be completely uniform. Further, CD3η-chain exon 8 amino acid sequences retained the unique characters of having high proline (Pro) and positively charged amino acid content except for rats and mice. Although the biological role of CD3η-chain remains to be enigmatic, these evidences suggests the evolutional pressure to maintain its sequence.  相似文献   
24.
We investigated whether interferon-gamma (IFN-gamma), interferon-alpha (IFN-alpha) and glucocorticoids affected the adhesion of T cells to human umbilical endothelial cells or human synovial cells. About 30% of peripheral blood T cells could bind to unstimulated endothelial cells, but only a few T cells could bind to unstimulated synovial cells. When both endothelial cells and synovial cells were cultured with recombinant IFN-gamma (rIFN-gamma), the percentage of T cell binding to both types of cells increased in a dose-dependent manner. rIFN-alpha and dexamethasone blocked the T cell binding to unstimulated endothelial cells. Furthermore, rIFN-alpha and dexamethasone suppressed T cell binding to both endothelial cells and synovial cells stimulated by IFN-gamma, and also inhibited intercellular adhesion molecule-1 (ICAM-1) expression on both endothelial cells and synovial cells stimulated by IFN-gamma. These results suggest that IFN-alpha and glucocorticoids may inhibit T cell binding to endothelial cells or synovial cells by modulating adhesion molecule expression on these cells.  相似文献   
25.
Type 1 IFN is thought to be implicated in the autoimmune process of SLE. Plasmacytoid dendric cells (DC), which are natural IFN-alpha producing cells, play a pivotal epipathogenic role in SLE. The present study was undertaken to investigate the phenotypic characteristics of peripheral blood DC in SLE patients in comparison with those of healthy controls. Samples from 20 SLE patients and 18 healthy controls were studied. Three-colour flow cytometry was performed to identify myeloid DC, as CD11c(+) lineage marker(-), and HLA-DR(+) cells and plasmacytoid DC, as BDCA-2(+) linage marker(-), and HLA-DR(+) cells. We used the whole blood 'lyse/no-wash' procedure, which allows precise counting of peripheral blood DC. BDCA-2(+) plasmacytoid DC and CD11c(+) myeloid DC were reduced in SLE patients compared with controls. Similarly, BDCA-3(+) DC were reduced in SLE patients. These results indicated that SLE patients had a reduced number of both BDCA-2(+) plasmacytoid DC and CD11c(+) myeloid DC. These alternations of the DC subset may drive the autoimmune response in SLE.  相似文献   
26.
K Migita  K Eguchi  Y Kawabe    S Nagataki 《Immunology》1995,85(4):550-555
T-cell antigen receptor (TCR), which is not itself a protein tyrosine kinase (PTK), is thought to be associated with at least two SRC-like PTKs, P59fyn and ZAP-70. Activation of these PTKs is required for T-cell signal transduction. The aim of the present study was to determine the roles of PTKs in peripheral T-cell activation, induced by in vivo bacterial superantigen administration. We demonstrated that in vivo staphylococcal enterotoxin B (SEB) administration induced an enhanced tyrosine phosphorylation in peripheral spleen T cells undergoing a programmed cell death. In vitro immunecomplex kinase assay using antibody against P59fyn showed increased fyn kinase activity in SEB-stimulated spleen T cells. We examined the effect of PTK-specific inhibitors on DNA fragmentation and programmed cell death of V beta 8 positive T cells following in vitro culture of SEB-primed spleen T cells. Our results indicated that pretreatment of SEB-activated T cells with PTK inhibitors reduced DNA fragmentation and programmed cell death of V beta 8 positive T cells. These findings suggest that PTK plays an important role in activation and apoptosis of peripheral T cells induced by in vivo SEB administration.  相似文献   
27.
Apoptotic cell death in acinar and ductal epithelial cells is thought to play an important role in the development of salivary gland dysfunction in patients with Sjogren's syndrome (SS). We examined the expression of anti-apoptotic molecules in salivary glands from patients with SS. The labial salivary glands from six human T-cell leukemia virus (HTLV)-I-seronegative and eleven HTLV-I-seropositive SS patients were analyzed by immunohistochemistry. In vitro experiments were performed with a human salivary gland cell line (HSG cells). Immunohistologic analyses revealed that Bcl-2 and Bcl-x were preferentially expressed in salivary infiltrating mononuclear cells more than acinar and ductal epithelial cells. In contrast, strong X chromosome-linked inhibitor of apoptosis protein (XIAP) expression was evident in both acinar and ductal epithelial cells. The pattern of expression of these anti-apoptotic molecules was similar in both HTLV-I-seropositive and HTLV-I -seronegative SS patients. Western blot analysis confirmed expression of XIAP in cultured HSG cells. The expression of XIAP in HSG cells was increased by IL-1beta, TGF-beta1, or IL-10. However, XIAP expression was down-regulated by TNF-alpha, which induced apoptotic cell death of HSG cells with an increase in caspase-3 activity. These effects of TNF-alpha in HSG cells were antagonized by IL-1beta, TGF-beta1, or IL-10. Our results suggest that XIAP is important in regulating apoptotic cell death of acinar and ductal epithelial cells in patients with SS.  相似文献   
28.
A rare placental site trophoblastic tumor (PSTT) in a 39-year-old female was studied. This tumor, protruding into the uterine cavity, was histologically similar to tumors in previously reported cases of PSTT. Ultrastructurally, the characteristic finding was the presence of perinuclear filaments. Also, the tumor cells were strongly positive for hPL by immunohistochemical method. These findings suggest that this was a tumor caused by neoplastic proliferation of the extravillous intermediate trophoblast.  相似文献   
29.
We evaluated the efficacy of mutants with a deletion of the stress response protease gene as candidates for live oral vaccine strains against Salmonella infection through infection studies with mice by using a Salmonella enterica serovar Typhimurium mutant with a disruption of the ClpXP or Lon protease. In vitro, the ClpXP protease regulates flagellum synthesis and the ClpXP-deficient mutant strain exhibits hyperflagellated bacterial cells (T. Tomoyasu et al., J. Bacteriol. 184:645-653, 2002). On the other hand, the Lon protease negatively regulates the efficacy of invading epithelial cells and the expression of invasion genes (A. Takaya et al., J. Bacteriol. 184:224-232, 2002). When 5-week-old BALB/c mice were orally administered 5 x 10(8) CFU of the ClpXP- or Lon-deficient strain, bacteria were detected with 10(3) to 10(4) CFU in the spleen, mesenteric lymph nodes, Peyer's patches, and cecum 1 week after inoculation and the bacteria then decreased gradually in each tissue. Significant increases of lipopolysaccharide-specific immunoglobulin G (IgG) and secretory IgA were detected at week 4 and maintained until at least week 12 after inoculation in serum and bile, respectively. Immunization with the ClpXP- or Lon-deficient strain protected mice against oral challenge with the serovar Typhimurium virulent strain. Both the challenged virulent and immunized avirulent salmonellae were completely cleared from the spleen, mesenteric lymph nodes, Peyer's patches, and even cecum 5 days after the challenge. These data indicate that Salmonella with a disruption of the ATP-dependent protease ClpXP or Lon can be useful in developing a live vaccine strain.  相似文献   
30.
Computer imaging analysis was used for quantitative evaluation of the extents, amounts and distributions of glomerular extracellular components, such as the 7S and NC 1 domains of type IV collagen, laminin (LN), fibronectin (FN) and IgA, in glomeruli from patients with IgA nephropathy. Renal biopsy specimens from 13 patients with IgA nephropathy were incubated with mouse monoclonal antibodies against the FN or non collagenous (NC 1) domain of type IV collagen or polyclonal antiserum against the LN or 7S domain of human type IV collagen, and then stained with appropriate dilutions of FITC labeled anti mouse Ig antisera. Marked staining of the 7S or NC 1 domain of type IV collagen, LN or FN was detected in the glomerular capillary walls and/or mesangial areas in patients with IgA nephropathy. In particular, a prominent increase of FN was observed in the subendothelial regions of glomerular capillary walls, i.e. mesangial interposition, in the moderate or advanced stage of IgA nephropathy. Therefore, computer imaging analysis was shown to be useful for the quantitative determination of such components distributed in glomeruli from patients with IgA nephropathy. Acta Pathol Jpn 39: 296 305, 1989.  相似文献   
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