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51.
Meningococcal tetravalent polysaccharide vaccines were observed to be immunogenic in Saudi children 5 to 9 years of age, with >90% having serum bactericidal antibody titers of > or = 8 for serogroups A, Y, and W135; for serogroup C, 77% were putatively protected after vaccination.  相似文献   
52.
53.
Protein composition of tomato spotted wilt virus   总被引:2,自引:0,他引:2  
Analysis of the protein composition of tomato spotted wilt virus (TSWV), purified by an improved procedure, by polacrylamide gel electrophoresis, revealed three major structural proteins (of MW 84,000, 50,000, and 29,000d) and a minor one of MW 220,000d. The three major proteins constitute about 98% of the total viral protein and all three were shown to be glycoproteins. One of the major proteins (MW 29,000d) and the minor protein were shown to be associated with subviral particles isolated by treatment of virus with the nonionic detergent Nonidet P-40. Only traces of the other two proteins were detected in the subviral particles.Synthesis of virus-induced proteins in TSWV-infected tobacco leaves was studied by labeling infected and healthy tissue with [3H]and [14C]valine, respectively. The labeled tissues were then fractionated into crude subcellular fractions and protein patterns of healthy and infected tissues were compared by coelectrophoresis on polyacrylamide gels. Only one virus-specific protein (of MW 49,000d) was detected in the virus-enriched fractions; this corresponded with the viral structural protein of MW 50,000d.  相似文献   
54.
In this study, we measured direct and indirect T-cell alloresponses mediated by CD4(+) and CD8(+) T cells in three mouse transplantation models: skin, cornea, and retina. We show that the contribution of direct and indirect antigen recognition pathways to the alloresponse to fully allogeneic grafts varies depending upon the nature of the tissue/organ transplanted. The implications of this finding for understanding the cellular mechanisms by which rejection is mediated in different transplant models are discussed.  相似文献   
55.
Treatment for extensive-stage small cell lung cancer (ES SCLC) or extrapulmonary small cell carcinoma (EPSC) is typically palliative. We set out to determine progression-free survival (PFS) and overall long-term survival of ES SCLC and EPSC patients, physiologically aged < or = 60 years, responding to first-line chemotherapy followed by high-dose combination alkylating agents with hematologic stem cell support. Patients in first-line chemotherapy response underwent stem cell collection (marrow, peripheral blood progenitor cells, or both) followed by high-dose therapy with 1 of 2 regimens: CBP (cyclophosphamide, cisplatin, and carmustine) or ICE (ifosfamide, carboplatin, and etoposide) with or without etanidazole. Involved-field radiotherapy was given to selected patients with oligometastatic disease distributed in sites allowing for reasonable radiation ports, and prophylactic cranial radiotherapy was given upon recovery to patients in complete response (CR) or near-CR. A total of 36 patients were treated. Of 29 patients with ES SCLC, 6 (21%) had achieved CR, 18 near-CR, and 5 partial response prior to high-dose therapy. Of 7 patients with EPSC, 3 (43%) had achieved CR, 3 had achieved near-CR, and 1 had progression of disease prior to high-dose therapy. Thirteen ES SCLC patients received high-dose CBP. Of the remaining 23 patients with SCLC or EPSC, 17 were treated with ICE and 6 with ICE plus etanidazole, a hypoxic cell sensitizer. Treatment-related mortality was 11% (4 of 36 patients). For all patients, the median event-free survival (EFS) was 5 months. The 2- and 5-year survivals after intensification were 12% (95% confidence interval [CI], 5%-31%) and 9% (95% CI, 3%-27%), respectively. Of the 30 patients in or near CR prior to high-dose therapy, 5 remain continuously progression-free (2 ES SCLC, 3 EPSC) for a median of 55 months (range, 1-96 months) after high-dose therapy. By multivariate analysis, factors associated with more favorable EFS were the use of a more aggressive induction regimen (ICE), and the EPSC histology. These factors were also associated with more favorable overall survival. Other factors associated with more favorable overall survival were the use of short induction therapy (< or = 4 cycles) and younger age (<50 years). Except for high-dose ICE with etanidazole, the use of high-dose systemic therapy in ES SCLC and EPSC was associated with low treatment-related morbidity and mortality over the past 5 years. Late complications were infrequent, and most patients returned to full-time work and activity, barring disease recurrence. Nonetheless, few patients with ES SCLC have progression-free long-term survival. We conclude that high-dose therapy is not indicated as an approach for ES SCLC, except as part of an investigative trial. Conversely, 3 of the 7 patients with EPSC remain relapse-free (range, 1-96 months), warranting further phase II evaluation of this approach in this population.  相似文献   
56.
A 71 year-old woman with a large tumor of the upper lobe of the left lung was diagnosed as having metastatic adrenal cortical carcinoma nine years after the initial adrenalo-nephrectomy. The patient was well with no recurrence for six years following resection of the single lung metastasis.  相似文献   
57.
Full-length deoxyribonucleic acid, complementary (cDNA) constructs encoding the-subunit of the adult human skeletal muscle Na+ channel, hSkM1, were prepared. Functional expression was studied by electrophysiological recordings from cRNA-injectedXenopus oocytes and from transiently transfected tsA201 cells. The Na+ currents of hSkM1 had abnormally slow inactivation kinetics in oocytes, but relatively normal kinetics when expressed in the mammalian cell line. The inactivation kinetics of Na+ currents in oocytes, during a depolarization, were fitted by a weighted sum of two decaying exponentials. The time constant of the fast component was comparable to that of the single component observed in mammalian cells. The block of hSkM1 Na+ currents by the extracellular toxins tetrodotoxin (TTX) and -conotoxin (CTX) was measured. The IC50 values were 25 nM (TTX) and 1.2 M (CTX) in oocytes. The potency of TTX is similar to that observed for the rat homolog rSkM1, but the potency of CTX is 22-fold lower in hSkM1, primarily due to a higher rate of toxin dissociation in hSkM1. Single-channel recordings were obtained from outside-out patches of oocytes expressing hSkM1. The single-channel conductance, 24.9 pS, is similar to that observed for rSkM1 expressed in oocytes.  相似文献   
58.
A kinetic study of the redox telomerization of vinyl chloride with carbon tetrachloride was carried out. Transfer constants of PVC to the metallic ion (CFen), initiation rate (ki), and functionnality of the resulting telomers were measured. Instantaneous and cumulated polymerization degrees, (DPn )i and (DPn )cum were determined with the help of a theoretical study. These constants provide a rigorous control of the telomerization of vinyl chloride with RCCl3, (R containing an alcohol or ester group).  相似文献   
59.
60.
Therapeutic application of broadly reactive anti-T cell antibodies can lead not only to potent immunosuppression but also to profound and long-lived T cell depletion. We reasoned that a strategy that almost exclusively targets activated cytopathic donor reactive T cells and spares immunoregulatory networks might prove to be an exceptionally potent and highly selective means of producing long-term engraftment and tolerance. Herein we show that the combined administration of rapamycin and agonist IL-2- and antagonist IL-15-related cytolytic fusion proteins provides for long-term engraftment/tolerance in exceptionally stringent allotransplant models by (1) limiting the early expansion of activated T cells, (2) preserving and even exaggerating their subsequent apoptotic clearance, and (3) further amplifying the depletion of these activated T cells by antibody-dependent mechanisms, while (4) preserving CD4+CD25+ T cell-dependent immunoregulatory networks.  相似文献   
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