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51.
We examined the effect of endobronchial (EB) or whole-lung (WL) challenge with ragweed or Timothy grass extract on alveolar macrophage (AM) activation. Expression of 17 constitutive activation markers on AM was examined by flow cytometry. Late-phase bronchial obstruction was greater after WL challenge, while changes in bronchoalveolar lavage cytology (eosinophil accumulation) were greater after EB challenge. After EB challenge, levels of 10 of 17 markers (CD11a, CD11b, CD14, CD18, CD23, CD32, CD63, CD64, HLA-class I, and HLA-DR) were significantly increased (by 33-234%, P < 0.05). Six markers (CD16, CD29, CD33, CD35, CD44, CD71, and HLA-DQ) remained unchanged. Levels of seven markers following EB challenge (CD14, CD16, CD18, CD29, CD32, HLA-class I, and HLA DQ) correlated with airway sensitivity to methacholine. WL challenge only increased expression of HLA-class I. The different results obtained with the two challenge methods probably depend on higher local concentrations of allergen in the EB challenge. We suggest that activation of AM occurs following EB challenge with antigen in asthmatics.  相似文献   
52.
The Flow-Fluorescence Cytometric Method (FCM) was applied to investigate the DNA content and the ploidy outlines of each of 96 glioblastomas. No specific DNA pattern was detected, possibly because of the tangle morphology of these variable tumors. Due to their capricious growth the DNA distribution proved to fluctuate greatly. Thus, the series, arranged according to increased PI (proliferation index) values, exhibited a wide spread within a total range from 7.1–97.15% (mean 39.3%) PI. A threefold subdivision of main types (I–III) appears to be of practical use for clinical prognostic assessment: diploid tumors with a PI range up to 10% (N=7) are followed by abnormal chiefly tretra- and hyper-tetraploid tumors up to PI values about 30% (N=21). The third category includes cases showing excessive aneuploidy combined more and more with polyploidy and valid stemlines, up to the PI maximum of about 97 rel.% (N=68). Thus, in 89 tumors clear pathological changes of DNA content can be decoded; of these 68 (76.4%) express a considerable aneuploidy and polyploidy respectively.Dedicated to Prof. Dr. HJ Bauer for his 75th birthday, March 31, 1989  相似文献   
53.
The influence of age on the occurrence of phenotypic features of prognostic significance was studied in relation to the DNA index values, measured on DNA histograms from a series of 1019 breast cancer patients. Globally, the distributions of all parameters showed variations with age, the most prominent being the decreases in the percentage of estrogen receptor-negative and high proliferative activity cases with increasing age. When analyzed according to the DNA index classes, all parameters were found to some extent linked with the stage of genetic evolution. However, the associations varied with age, defining two extreme groups. The younger patients (less than 40 years) presented a more complete acquisition of the aggressive phenotype and near-triploid tumors from this group were very frequently steroid hormone receptor-negative, high proliferation, and grade III. By contrast, near-triploid tumors in patients above 65 presented relatively frequently as receptor-positive, low proliferative activity, and even grade I. The correlation of the proliferative status with steroid hormone receptor content led to similar conclusions, high proliferation being more strongly correlated with the absence of estrogen and progesterone receptors in younger patients. Interestingly, the association between high proliferation and negative progesterone receptors was much weaker in patients above 55. Our results suggest that the currently established biological prognostic factors, including DNA profile, steroid hormone receptors, and histopathological grade, show patterns of association which vary with age. Of these, only progesterone receptor could be influenced by menopausal status. These findings have to be taken into consideration for future prognostic factor-related treatment decisions, but also for future methodological improvements of multivariate survival analyses.  相似文献   
54.
Leukocytes adherent to the surfaces of both vascular biomaterials and normal blood vessels experience blood flow induced shear stress. The goal of the reported studies was to investigate the effect of fluid flow on the morphology, phagocytic function and stress response induction in adherent immune cells. Shear approximating arterial, venous and intermediate levels were applied onto glass-adherent IC21 macrophages in a temperature-controlled parallel plate flow system. The results indicate that fluid flow induces a shear-dependent physiological stress response in adherent macrophages and that significant morphological changes accompany macrophage responses to shear stress. In addition, arterial flow conditions induce not only significant cell polarisation, but also enhanced phagocytic ingestion in glass-adherent IC21 macrophages. These findings suggest that blood flow induced shear stress may not only be consequent to adherent leukocyte activation, but may also be integral to the regulation of adherent leukocyte behaviour in vivo.  相似文献   
55.
Infiltration of brain neoplasms by mononuclear cells including monocytes/macrophages has attracted little attention since they have marked morphological heterogeneity. Twenty-seven meningiomas were studied by anti-CD68 antibody-gated flow cytometry and by immunohistochemical analysis using the anti-CD68 antibodies. Flow cytometric analysis divided cells contained within tumor tissues into CD68-positive and -negative cells. In addition, eight gliomas, eight metastatic brain tumor, and 12 pituitary adenomas were investigated in the same way to compare meningiomas. The mean contents of CD68-positive cells were 24.0±3.7% in meningiomas, 4.4±1.4% in gliomas, 9.5±3.9% in metastatic brain tumors, and 4.5±1.8% in pituitary adenomas. Immunohistochemically, CD68-positive cells showed significant heterogeneity and were detected as round, rod-shaped, ameboid and ramified cells in meningiomas. Although the infiltrated mononuclear cells in gliomas have been investigated to some degree and showed that they express cytokines and/or growth factors, these infiltrated cells in meningioma have barely been studied. The CD68-positive cells detected in this study are likely to be monocytes, macrophages and microglias, and are presumed to be in various functional stages and to play important roles in growth regulation in meningioma.  相似文献   
56.
姚晓明  徐锦堂  李辰 《眼科》1999,8(1):48-51
目的;研究异种表面角膜术后机体对异种角膜的免疫反应,阐明人体对异种角膜的免疫耐受机制。方法:应用流式细胞仪对9例接受异种表面角膜镜片术患者术后外周血T细胞的分布和自然杀伤细胞的活性进行了分析。结果;术后2个月,T细胞末被激活,NK活化程度显著提高,但未激发排斥反应。结论;猴角膜镜片虽可诱发轻微的免疫应答,但未达到增强抗原诱发的T细胞增殖应答的程度。  相似文献   
57.
A new flow cytometric method was developed to detect apoptotic cells with fragmented DNA and to determine cell cycle distribution of viable cells, in the same sample, by propidium iodide staining. Apoptosis, in HT58 human B lymphoma cells, was induced by etoposide and/or by staurosporine. Using appropriate alkaline solutions (between 1-10 mN NaOH in 150 mM saline) followed by neutralization with buffer solution, the fragmented DNA can be extracted quantitatively from ethanol fixed cells. Further, good resolution of the cell cycle distribution can be obtained in unimpaired cells without RNase treatment. Furthermore, unlike the widely used hypotonic-detergent extraction of unfixed cells, the suggested extraction method can prevent drug-induced disintegration of dead cells when karyorrhexis occurs. This work was supported by Hungarian National Research Foundation (OTKA I/352 and OTKA II/2622).  相似文献   
58.
Stenosis phantoms were created to study the ability of "black blood" methods to image a vessel stenosis in the presence of pulsatile flow. Black blood images were acquired with a modified TurboFLASH (fast low-angle shot) method that eliminates flow signal by applying a set of prepulses before segmented data acquisition. With this high-speed approach, imaging can be completed within 16 seconds. This technique was compared with conventional spin-echo black blood, gradient-echo black blood, and gradient-echo bright blood methods. Loss of flow signal, which extended beyond the site of the stenosis, was seen on the gradient-echo bright blood images. The pattern of signal loss varied with the type of stenosis. Flow voids were achieved with spin-echo black blood imaging; however, substantial ghosting artifacts were seen. With gradient-echo black blood imaging, it was difficult to eliminate all flow signal, particularly for in-plane flow. The modified TurboFLASH method produced high-quality black blood images in a fraction of the time needed for spin-echo imaging. It showed no ghosting artifacts even in the presence of pulsatile flow.  相似文献   
59.
目的 :探讨原因不明习惯性流产 (UHA)患者蜕膜自然杀伤 (NK)细胞的数量、表型特征及杀伤活性 ,探讨其在UHA发病中的作用。方法 :选取确定妊娠并难免流产的UHA 32例 ,选取 2 0例正常妊娠行人工流产者作为对照组 ,用流式细胞仪检测两组蜕膜组织中NK细胞数量及表型 ,用改进的乳酸脱氢酶释放法测定NK细胞杀伤活性。结果 :正常早孕蜕膜中CD5 6+CD3- NK细胞占蜕膜单个核细胞的 60 .73± 13.2 4 % ,为蜕膜组织的优势细胞群 ,UHA患者蜕膜中CD5 6+CD3- NK细胞总量与正常妊娠蜕膜组织中相同 ,而其CD5 6+CD16- 亚群却明显低于正常妊娠组 (P <0 .0 5 ) ,CD5 6+CD16+亚群含量及CD5 6+CD16+/CD5 6+CD16- 比值均异常增高 (P均 <0 .0 5 )。UHA组蜕膜组织中NK细胞杀伤活性及其异常增高率均高于正常妊娠组 ,差异均有显著性 (P均 <0 .0 5 )。结论 :NK细胞是孕早期蜕膜组织中的优势细胞群 ,其亚群失衡及功能异常可导致自然流产  相似文献   
60.
大鼠脑神经干细胞神经巢蛋白表达的流式细胞术检测   总被引:9,自引:1,他引:8  
检测胎鼠及成年大鼠脑内神经干细胞特异性抗原神经巢蛋白的表达,判明啮齿类哺乳动物脑内神经干细胞存在的可能性及相应的部位。方法:显微手术下采取胎鼠及成年大鼠大脑与皮质下脑组织,间接荧光法标记nestin,以流式细胞术检测。结果胎鼠脑内普遍存在nestin阳性细胞,成年大鼠脑室旁组织中也存在nestin阳性细胞。  相似文献   
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