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11.
T lymphocytes play a fundamental role in the initiation and regulation of chronic inflammatory responses in patients with asthma. CD69 is an early marker of T‐cell activation. The levels of intercellular adhesion molecule‐1 (ICAM‐1, CD54) and L ‐selectin have been reported to increase in patients with allergic diseases and asthma. The present study was therefore undertaken to investigate the expression of CD69, CD54, and L ‐selectin by T lymphocytes of children with asthma, before and after immunotherapy. Eighteen children newly diagnosed with asthma, 11 good and nine poor responders to immunotherapy, and 16 normal subjects, were enrolled in this study. The percentages of CD69+, CD54+, and CD62L+ cells in T lymphocytes were measured by using flow cytometry. The levels of CD69, CD54, and CD62L in serum and culture supernatants were determined by using enzyme‐linked immunosorbent assay (ELISA). The expression of CD69 and CD54 on CD3+ T lymphocytes was significantly higher in children with asthma than in control patients. All the patient groups expressed (spontaneously and following stimulation with phorbol myristate acetate and ionomycin together with mite‐extract proteins) greater amounts of CD69 and CD54 than did control subjects. With long‐term immunotherapy, the percentages of CD69+ and CD54+ T lymphocytes were significantly lower in patients with a good response to immunotherapy. Our results also showed significantly lower serum L ‐selectin levels following immunotherapy. In conclusion, successful immunotherapy resulted in decreased expression and production of CD69 and CD54. These results may explain, in part, the clinical efficacy of immunotherapy.  相似文献   
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M W Long  N Williams 《Blood》1981,58(5):1032-1039
Three types of immature megakaryocytes, detected by their morphological properties, have been characterized in bone marrow of normal C57BL/6 mice. Morphological classification of these cells was carried out by determining (1) presence and relative amount of acetylcholinesterase, (2) cell size, (3) nuclear/cytoplasm ratio, and (4) nuclear shape. The immature megakaryocytes were classified as: (A) cells distinguished by a round nucleus (10.6 +/- 1.1 mu diameter; mean +/- SEM), which had the highest nucleus / cytoplasm ratio and lowest content of acetylcholinesterase; (B) cells with an indented nucleus (13.0 +/- 1.9 mu diameter), which had increased acetylcholinesterase content and reduced nucleus/cytoplasm ratio compared to the round-nucleus cell type; and (C) lobed-nucleus cells (14.5 +/- 2.9 mu diameter), which showed further increase in acetylcholinesterase content and reduction in nucleus/cytoplasm ratio. Increased numbers of immature megakaryocytes were detected, indicating that a proportion of these cells are undetected using conventional staining techniques. Based on the observed alterations in size, acetylcholinesterase content, and nuclear complexity, it was concluded that these cells constitute part of a progressive maturation sequence intermediate between the progenitor cell (CFU-Mk) and mature easily recognizable megakaryocytes.  相似文献   
14.
Nitric oxide (NO), originally identified as the mediator of endothelial-dependent relaxation of vascular smooth muscle, is now known to also have cytotoxic effects under certain conditions. Thus, we have investigated the effects of inhibition of NO synthesis on ischemia/reperfusion injury in the rabbit rectus femoris muscle. Three and a half hours of ischemia and 24 hours of reperfusion resulted in a 56% loss of viability. In muscles receiving an infusion of the nitric oxide synthase inhibitor, L-NIO (30 μM), the loss of viability was reduced to 15%. Post-ischemic blood flow was increased in muscles receiving a saline infusion, whereas there was a marked decrease in blood flow for at least the first 60 minutes of reperfusion in muscles treated with L-NIO (30 μM). The increase in myeloperoxidase levels (indicative of neutrophil accumulation) following 24 hours of reperfusion was attenuated with L-NIO infusion by approximately 50% and the reperfusion-induced edema was also attenuated in L-NIO treated muscle. These findings suggest that endogenous NO production during ischemia/reperfusion injury may be deleterious to muscle survival. © 1994 Wiley-Liss, Inc.  相似文献   
15.
用二甲苯所致的急性炎症模型观察了神效止痛膏的抗急性炎症作用.用扭体法、热板法观察了神效止痛膏对小鼠的镇痛作用.结果表明,神效止痛膏有很好的镇痛作用.  相似文献   
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17.
A genome-wide screen was conducted using a large white sample to identify QTLs for FNCS geometry. We found significant linkage of FNCS parameters to 20q12 and Xq25, plus significant epistatic interactions and sex-specific QTLs influencing FNCS geometry variation. INTRODUCTION: Bone geometry, a highly heritable trait, is a critical component of bone strength that significantly determines osteoporotic fracture risk. Specifically, femoral neck cross-sectional (FNCS) geometry is significantly associated with hip fracture risk as well as genetic factors. However, genetic research in this respect is still in its infancy. MATERIALS AND METHODS: To identify the underlying genomic regions influencing FNCS variables, we performed a remarkably large-scale whole genome linkage scan involving 3998 individuals from 434 pedigrees for four FNCS geometry parameters, namely buckling ratio (BR), cross-sectional area (CSA), cortical thickness (CT), and section modulus (Z). The major statistical approach adopted is the variance component method implemented in SOLAR. RESULTS: Significant linkage evidence (threshold LOD = 3.72 after correction for tests of multiple phenotypes) was found in the regions of 20q12 and Xq25 for CT (LOD = 4.28 and 3.90, respectively). We also identified eight suggestive linkage signals (threshold LOD = 2.31 after correction for multiple tests) for the respective geometry traits. The above findings were supported by principal component linkage analysis. Of them, 20q12 was of particular interest because it was linked to multiple FNCS geometry traits and significantly interacted with five other genomic loci to influence CSA variation. The effects of 20q12 on FNCS geometry were present in both male and female subgroups. Subgroup analysis also revealed the presence of sex-specific quantitative trait loci (QTLs) for FNCS traits in the regions such as 2p14, 3q26, 7q21 and 15q21. CONCLUSIONS: Our findings laid a foundation for further replication and fine-mapping studies as well as for positional and functional candidate gene studies, aiming at eventually finding the causal genetic variants and hidden mechanisms concerning FNCS geometry variation and the associated hip fractures.  相似文献   
18.
Recognition of the many benign and malignant tumors that occur in the skull base is now simple, given three-dimensional CT scanning and MRI with enhancement. Recent developments in surgical technique have allowed these tumors to be approached, but only in the past two to three years has radical surgery been possible.  相似文献   
19.
A double-contrast upper gastrointestinal examination on a woman who had undergone endoscopic heater probe therapy one day earlier for multiple arteriovenous malformations revealed shallow, irregular, and linear ulcers at the sites of heater probe coagulation. Multiple shallow ulcers may therefore develop as a direct complication of heater probe therapy. Radiologists should be aware of this complication to avoid diagnostic confusion in these patients.  相似文献   
20.
High-specificity in-situ hybridization. Methods and application.   总被引:2,自引:0,他引:2  
We describe a technique of in-situ hybridization using oligonucleotide probes employing the expression of immunoglobulin VH genes as a model. Optimal conditions for hybridization with the 35S-labeled oligonucleotide probes were established with monoclonal B-cell lines that express VH genes of known nucleic acid sequence. The range of sensitivity and specificity achieved with this technique is documented. Under conditions of high stringency, this method can detect the expression of highly related VH hypervariable regions.  相似文献   
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