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11.
Utilization of murine peripheral blood lymphocytes for H-2 typing   总被引:1,自引:0,他引:1  
We adapted the NIH Standard Protocol for HLA-A, B, C typing to perform murine H-2 typing. The assay is direct, measuring the cytotoxicity of the antiserum/cell/complement reaction with a supravital dye. This method is advantageous because it: utilizes peripheral blood lymphocytes (PBL) obtained from the tail vein; uses microliter volumes of antiserum; is practical because the formalin fixed reactions need not be read immediately; involves standard and inexpensive cytotoxicity techniques; is easily interpreted and is readily reproducible.  相似文献   
12.
We report a case of Waldenstr?m macroglobulinemia with trisomy 4 as the sole cytogenetic abnormality. Trisomy 4 has been reported previously in Waldenstr?m macroglobulinemia, but only in conjunction with multiple chromosomal aberrations. Trisomy 4 has been reported in other hematologic malignancies including acute myeloid and lymphoid leukemias.  相似文献   
13.
A patient with the clinical stigmata of gonadal dysgenesis is presented. Cytogenetic investigations revealed two distinct structural chromosome rearrangements. One of these, an isochromosome for the long arm of the X, proved to be a dicentric element following C-banding. The second abnormality, an inherited familial marker, was a pericentric inversion of No. 2 [(inv 2) (p15q21)].  相似文献   
14.
Cytochemical localization of tartrate-resistant acid phosphatase (TRAP), tartratc-sensitive acid phosphatases (TSAP), alkaline phosphatase, and nonspecific esterase was used to characterize perivascular cells within cartilage canals. In the distal femoral epiphyses of 5- to 7-day-old mice, three stages of canal development can be distinguished, and at each developmental stage different perivascular cells were present with morphological characteristics of degradative cells. Vacuolated cells resembling macrophages, fibroblastic cells, and chondroclasts were present adjacent to the matrix in superficial, intermediate, and deep canals, respectively. In order to characterize these perivascular cells cytochemically, nonspecific esterase and TSAP staining was used to identify macrophages, alkaline phosphatase staining was used to identify fibroblastic cells, and TRAP staining was used to identify chondroclasts. There were no cells present in the canals at any developmental stage that were positive for TSAP or strongly positive for nonspecific esterase, placing doubt on the identity of the vacuolated cells as macrophages. Alkaline phosohatase-positive perivascular cells were present in the intermediate and deep canals adjacant to matrix containing alkaline phosphatase-positive chondrocytes. These alkaline phosphatase-positive cells were found in the same location within canals as the fibroblastic cells. Tartrate-resislant acid phosphatase was localized in chondroclasts at the tips of deep canals but was not confined exclusively to chondroclasts. Except for the very early stage of canal development prior to chondrocyte hypertrophy, TRAP-positive cells were present at the tips of superficial and intermediate canals as well as at the tips of the deep canals. Additionally, the presence of TRAP in chondrocytes with in the growth plate, in chondrocytes within the epiphyseal cartilage near some canals, and in perichondrial cells suggests that TRAP is associated with matrix degradation in the cartilage.  相似文献   
15.
Trichophyton tonsurans infections occur in various host populations, on various body sites and with varying degrees of inflammation. This investigation was undertaken to determine whether fungal factors could explain the degree of severity in clinical symptomatology among infected children. Otherwise healthy children (n=54) presenting with tinea capitis were enrolled in this study. A thorough history was performed, the extent and severity of infection graded and a fungal specimen collected from each child. Strain type was determined by genotyping for 11 sequence variations in the rDNA and ALP1 loci. Secreted protease activity was quantitated after 5 days of growth in aqueous medium. Forty participants were evaluable. Infection duration ranged from 1 day to 3 years and clinical severity score (CSS) from 4-19. Seventeen unique fungal genotypes were present. Keratinase, collagenase and elastase activity varied 32.7-fold, 64.9-fold and 303.3-fold, respectively. A significant association was observed between genotype and disease severity with the rDNA sequence variations accounting for over 50% of the variation observed in CSS (r2=0.539; P<0.001). Phylogenetic analyses appear to suggest that the ancestral strain types of T. tonsurans cause more severe disease. These observations are consistent with reports that recently diverge anthropophilies are associated with diminished inflammatory involvement.  相似文献   
16.
In several murine models of transplantation, the “cross-dressing” of recipient antigen presenting cells (APCs) with intact donor major histocompatibility complex (MHC) derived from allograft-released small extracellular vesicles (sEVs) has been recently described as a key mechanism in eliciting and sustaining alloimmune responses. Investigation of these processes in clinical organ transplantation has, however, been hampered by the lack of sensitivity of conventional instruments and assays. We have employed advanced imaging flow cytometry (iFCM) to explore the kinetics of allograft sEV release and the extent to which donor sEVs might induce cross-dressing following liver and kidney transplantation. We report for the first time that recipient APC cross-dressing can be transiently detected in the circulation shortly after liver, but not kidney, transplantation in association with the release of HLA-bearing allograft-derived sEVs. In liver transplant recipients the majority of circulating cells exhibiting donor HLA are indeed cross-dressed cells and not passenger leukocytes. In keeping with experimental animal data, the downstream functional consequences of the transfer of circulating sEVs harvested from human transplant recipients varies depending on the type of transplant and time posttransplant. sEVs released shortly after liver, but not kidney, transplantation exhibit immunoinhibitory effects that could influence liver allograft immunogenicity.  相似文献   
17.
PURPOSE: To investigate the safety and tolerability and to explore the pharmacokinetic and pharmacodynamic profile of the humanized antiepidermal growth factor receptor monoclonal antibody EMD72000 in patients with solid tumors that express epidermal growth factor receptor (EGFR). PATIENTS AND METHODS: This was a phase I dose-escalation trial of EMD72000 in patients with advanced, EGFR-positive, solid malignancies that were not amenable to any established chemotherapy or radiotherapy treatment. EMD72000 was administered weekly without routine premedication until disease progression or unacceptable toxicity. RESULTS: Twenty-two patients were treated with EMD72000 at five different dose levels (400 to 2,000 mg/wk). National Cancer Institute common toxicity criteria grade 3 headache and fever occurring after the first infusion were dose limiting at 2,000 mg/wk; thus, the maximum-tolerated dose was 1,600 mg/wk. No other severe side effects, especially no allergic reactions or diarrhea, were observed. Acneiform skin reaction was the most common toxicity, but it was mild, with grade 1 in 11 patients (50%) and grade 2 in three patients (14%). Pharmacokinetic analyses demonstrated a predictable pharmacokinetic profile for EMD72000. Pharmacodynamic studies on serial skin biopsies revealed that EMD72000 effectively abrogated EGFR-mediated cell signaling (eg, reduced phosphorylation of EGFR and mitogen-activated protein kinase), with no alteration in total EGFR protein. Objective responses (23%; 95% CI, 8% to 45%) and disease stabilization (27%; 95% CI, 11% to 50%) were achieved at all dose levels, and responding patients received treatment for up to 18 months without cumulative toxicity. CONCLUSION: Treatment with EMD72000 was well tolerated and showed evidence of activity in heavily pretreated patients with EGFR-expressing tumors. EMD72000 at the investigated doses significantly inhibited downstream EGFR-dependent processes.  相似文献   
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OBJECTIVE: To construct and validate a computer instrument that identifies asthma patients receiving--theoretically--suboptimal drug therapy in community pharmacies, by the use of patient medication records. This selection enables the pharmacist to assist these patients in using medicines appropriately. METHODS: According to Dutch asthma guidelines which describe a stepwise approach and in order to define correct profiles for the use at each level of these guidelines, the optimum use of drugs in the different levels in asthma treatment was expressed in defined daily doses (DDDs) per pharmacological drug-group during a period of one year. An algorithmic computer instrument was developed to select patients with medication use deviant from these profiles. By using nine different selection profiles, the computer instrument stratified patients according to the medication records filed in the pharmacy computer. Patient medication records in four community pharmacies were investigated to validate the selection profiles as indicators for theoretically suboptimal drug use by asthma patients. The validation was performed by comparing the professional judgement of participating pharmacists with the selections made by the computer. MAIN OUTCOME MEASURE: Positive predictive value and negative predictive value of the selection made by algorithmic computer instrument. Rate of false-positive results. RESULTS: The computer instrument identified asthma patients using theoretically suboptimal drug therapy with approximately 95% predictive value compared with the professional judgement of the pharmacists. The rate of false-positive results was 5%. CONCLUSION: The results of the algorithmic computer instrument and the professional judgement of the pharmacists are in close agreement. The instrument will be utilised in further research in the IPMP study (Interventions on the principle of Pulmonary Medication Profiles) investigating the role of Dutch community pharmacists in counselling patients who are at risk of suboptimal drug use in the treatment of their asthma.  相似文献   
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