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The communication between tumor stromal and parenchymal cells provides an insight to tumor progression. One of the main elements of the stroma, a major contributor to the extracellular environment of tumors, is carcinoma‐associated fibroblasts. They can originate from either normal fibroblasts in the immediate vicinity of the tumor or from circulating bone marrow–derived mesenchymal stem cells. These myofibroblasts can arise locally from an endothelial–mesenchymal transformation at the invasive edge of the cancer and are physically associated with carcinoma cells, that is, in the development of high‐grade malignancies and poor prognosis. These carcinoma‐associated fibroblasts feed the epithelial tumor cells in a host–parasite relationship establishing its role in head and neck squamous cell carcinoma progression. 相似文献
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A perfluorocarbon blood substitute, Fluosol, is undergoing clinical trials as an adjunct to chemotherapy. The adverse effects associated with its administration have been postulated to result from complement activation. When gel electrophoresis and Western blotting of Fluosol are used after its incubation with serum, activated C3 and factors Bb and H are bound to the Fluosol particles in a time-dependent fashion, which suggests that complement activation with Fluosol, as does that with zymosan, occurs on the surface of the particles. Paradoxically, it is found, both by the measurement of Fluosol-bound C3d and by fluid-phase C5a, that lower concentrations of Fluosol cause greater amounts of complement activation, which suggests a complex interaction of activators and inhibitors that changes as the available surface area is decreased. Studies performed with bystander red cell-bound C3d demonstrated in vivo complement activation occurring in six patients receiving Fluosol as an adjunct to chemotherapy for colon cancer. In two patients, there was a marked increase in red cell-bound C3d after Fluosol infusion; these two patients also developed adverse reactions during Fluosol infusion. These studies suggest that the Fluosol surface plays a major role in the initiation and regulation of complement activation that is seen during Fluosol infusion. 相似文献
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J Williams DCH FRCP KA Richards MSc UK Study Group 《International journal of clinical practice》1997,51(3):147-153
A total of 323 children aged 4-11 years who were receiving, or had symptoms indicating a clinical requirement for, inhaled corticosteroid at a daily dose of 400 μg budesonide (BUD) or beclomethasone dipropionate (BDP), or 200 μg fluticasone propionate (FP), were randomised into this multicentre, open-label, parallel group study. Patients received either FP 100 μg b.d. administered via the Accuhaler/Diskus inhaler (n=159) or BUD 200 μg b.d. administered via a Turbohaler inhaler (n=164) for four weeks and recorded daily their morning and evening peak expiratory flow (PEF), asthma symptoms and use of relief medication. Device handling was assessed by a questionnaire, with responses recorded on three- or five-point ordinal scales. The primary efficacy parameter was mean percent predicted morning PEF. The device handling results showed the Accuhaler/Diskus inhaler was rated more favourably than the Turbohaler inhaler in terms of ease of correct inhaler use, ease of telling how many doses were left, ease of knowing whether a dose had been inhaled and overall liking of the device. More patients in the Accuhaler/Diskus group (85%) than in the Turbohaler group (58%) said they would be happy to receive the same device again, while 8% and 25% respectively said they would not be happy to be given it again. In addition, the change from baseline to week 4 of treatment in mean percent predicted morning PEF was greater in the FP Accuhaler/Diskus group, indicating that FP 200 μg daily via Accuhaler/Diskus inhaler is at least as clinically effective as BUD 400 μg daily via the Turbohaler inhaler. 相似文献
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<正>电子结肠镜检查是诊断和筛查肠道疾病常用、有效的检查方法之一,而进行结肠镜检查的基本条件是清洁良好的肠道准备。虽然近年来肠道清洁剂的商品化和肠道准备方法的标准化不断完善,但仍有约30%的患者肠道准备不充分[1-3]。不充分的肠道准备会导致检查时间延长、操作难度增加、病变检出率降低、漏诊及检查费用增加等。肠道准备的质量多与患者的依从性有关,加强对患者肠道准备相关知识的教育,增强患者对肠道准备方法的认识和理解,可以提高检查前的肠道准备质量[4 相似文献
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Progressive platelet activation with storage: evidence for shortened survival of activated platelets after transfusion 总被引:14,自引:0,他引:14
HM Rinder ; M Murphy ; JG Mitchell ; J Stocks ; KA Ault ; RS Hillman 《Transfusion》1991,31(5):409-414
Platelets are known to become activated during storage, but it is unclear whether such activation affects recovery or survival after platelet concentrate (PC) transfusion. With the use of flow cytometry to determine the percentage of platelets expressing the alpha-granule membrane protein 140 (GMP-140), a known adhesive ligand appearing on the platelet surface after activation, several studies were conducted. These investigations evaluated 1) the occurrence of significant platelet activation over time in PCs (n = 46) stored under standard blood bank conditions; 2) the correlation between platelet activation and platelet recovery in normal subjects after PC storage (n = 12), as assessed by the recovery of Indium-labeled platelets; and 3) the recovery of activated and unactivated platelets in thrombocytopenic cancer patients transfused with standard PCs (n = 11). It was determined 1) that an increasing duration of storage of PC was associated with increasing platelet activation as measured by the percentage of platelets expressing GMP-140, progressing from a mean of 4 +/- 2 percent (SD) on the day of collection to a mean of 25 +/- 8 percent by 5 days of storage: 2) that, in normal subjects, posttransfusion recovery of autologous platelets stored for 2 to 4 days and then labeled with In111 was inversely correlated with the percentage of activated platelets in the transfused PC (r = -0.55, p = 0.05); and 3) that, when thrombocytopenic patients were transfused with standard PCs, the recovery of the activated platelets in the transfused PCs averaged only 38 +/- 15 percent of the number predicted by the absolute platelet increment.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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We have found that the addition of 10 mM inorganic phosphate to DHA in CPD-adenine maintains ATP levels at normal or higher than normal values for six weeks of storage. 2,3-DPG values are slightly lowered by the extra phosphate, but are still maintained at approximately half normal for four weeks by the DHA. The addition of a higher phosphate concentration, 20 mM, to DHA produced lower levels of ATP and 2,3-DPG than those observed with 10 mM phosphate, although both levels were better than in the CPD-adenine control. pH values in this experiment were lowest in the three preservatives containing DHA, probably indicating increased lactate production due to metabolism of this triose sugar, in addition to dextrose present in CPD. 相似文献