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排序方式: 共有873条查询结果,搜索用时 10 毫秒
31.
Storb R; Raff RF; Appelbaum FR; Deeg HJ; Graham TC; Schuening FG; Shulman H; Yu C; Bryant E; Burnett R 《Blood》1994,84(10):3558-3566
Previous studies found that bone marrow (BM) allografts from DLA- identical littermates resulted in survival of two thirds of recipient dogs after otherwise lethal doses of 450 to 600 cGy of total body irradiation (TBI) because of successful allografts or autologous recovery after rejection of the allografts. The current study asked whether survival could be further improved by treating allograft recipients with recombinant canine granulocyte colony-stimulating factor (G-CSF), stem cell factor (SCF), or G-CSF/SCF. Of 21 dogs, 14 (67%) receiving allografts but no growth factors survived, 10 with successful allografts (including 5 mixed chimeras) and 4 with autologous recovery; whereas 7 animals died, 5 from infections during BM aplasia and 2 from acute graft-versus-host disease. By comparison, 30 of 34 dogs (88%) receiving hematopoietic growth factors in addition to the BM graft survived, 17 with successful allografts (including 10 mixed chimeras) and 13 with autologous recovery; whereas 4 died, all with infection related to BM aplasia after rejection of the allograft. Survival was similar for recipients of G-CSF, SCF, or the combination of G-CSF and SCF. Logistic regression analyses, which accounted for possible effects of TBI dose, showed a trend for improved survival in dogs receiving growth factors (P = .09), no change in allogeneic engraftment (P = .74), and a slight increase in autologous recovery (P = .22). In agreement with previous data, we found that grafts of BM from DLA-identical littermates improved survival of recipient dogs exposed to low but otherwise lethal doses of TBI. A further improvement in survival could be achieved by additional treatment with G-CSF, SCF, or G-CSF/SCF. Results suggest that treatment by hematopoietic growth factors along with BM grafts should be considered for victims of radiation accidents. 相似文献
32.
Quality control of multidrug resistance assays in adult acute leukemia: correlation between assays for P-glycoprotein expression and activity 总被引:1,自引:5,他引:1
Broxterman HJ; Sonneveld P; Feller N; Ossenkoppele GJ; Wahrer DC; Eekman CA; Schoester M; Lankelma J; Pinedo HM; Lowenberg B; Schuurhuis GJ 《Blood》1996,87(11):4809-4816
We have compared multiple assays for the P-glycoprotein (Pgp/MDR1) phenotype in fresh and thawed adult acute leukemia to validate and quantitate measures for the expression and function of Pgp. The results are related to the Pgp-expressing KB8 and KB8-5 call lines. The most sensitive assay was the measurement of modulation of the rhodamine 123 (R123) fluorescence by 2 micromol/L PSC833, followed by the modulation of the probe calcein-AM. We also found a good intralaboratory and interlaboratory correlation between the values of the R123/PSC833 assay for fresh as well as thawed samples. In addition, the affects of PSC833 on 3H-daunorubicin (DNR) accumulation, DNR fluorescence, and 3H- vincristine accumulation were very similar. The correlation between the DNR/PSC833 and R123/PSC833 test was r = .86 (N = 51). The modulation of drug accumulation by 8 micromol/L verapamil was the some as the PSC833 effect for DNR (117%, N = 21), but was higher for vincristine in every single case (161% v 121%, N = 22; P< .001), indicating additional verapamil effects, not related to Pgp. The correlation of the staining of viable cells for Pgp with the monoclonal antibody MRK16 was r = .77 (N = 52) for the R123/PSC833 functional test and r = .84 (N = 50) for the DNR/PSC833 test. From these results it could be calculated that a maximal increase of the mean DNR accumulation of about 50% can be achieved by blocking Pgp pump activity with PSC833 in leukemic blast samples with the highest mean Pgp expression. Subpopulations of blast calls with higher Pgp activity are likely to be present. Their relevance has to be studied further. The methods outlined here allow the reliable, quantitative monitoring of the Pgp/MDR1 phenotype in leukemias in multicentered, clinical Pgp modulation studies. 相似文献
33.
von den Driesch P; Bhardwaj R; Flad HD; Neugebauer DC; Pielken HJ; Urbanitz D; Kolsch E 《Blood》1989,74(1):430-436
An immunoglobulin M (IgM)-positive cell line, Ms 28, apparently spontaneously transformed by Epstein-Barr virus (EBV) was established from peripheral blood cells of a patient with immature myeloblastic leukemia. It has been characterized according to phenotype, cytochemistry, and membrane antigen pattern. The cell line expresses lymphoid markers like CD 19, CD 22, and CD 30 and synthesizes and secretes IgM. Monocyte markers CD 11c, CD 14, and CD 15 are absent. Neither interleukin-1 (IL-1), nor tumor necrosis factor (TNF-alpha) are produced. But Ms 28 cells show strong phagocytic activity and engulf Latex particles and sheep RBCs (SRBCs) that need not to be opsonized. The phagocytic activity can be inhibited by chloroquine. Both phagocytosis and EBV nuclear-antigen (EBNA) expression can be observed in one and the same cell. Ms 28 cells might be useful to study immunologic activities like antigen processing and presentation. 相似文献
34.
Aven‐mediated checkpoint kinase control regulates proliferation and resistance to chemotherapy in conventional osteosarcoma 下载免费PDF全文
Zuzanna Baranski Tijmen H Booij Anne‐Marie Cleton‐Jansen Leo S Price Bob van de Water Judith VMG Bovée Pancras CW Hogendoorn Erik HJ Danen 《The Journal of pathology》2015,236(3):348-359
Conventional high‐grade osteosarcoma is the most common primary bone sarcoma, with relatively high incidence in young people. In this study we found that expression of Aven correlates inversely with metastasis‐free survival in osteosarcoma patients and is increased in metastases compared to primary tumours. Aven is an adaptor protein that has been implicated in anti‐apoptotic signalling and serves as an oncoprotein in acute lymphoblastic leukaemia. In osteosarcoma cells, silencing Aven triggered G2 cell‐cycle arrest; Chk1 protein levels were attenuated and ATR–Chk1 DNA damage response signalling in response to chemotherapy was abolished in Aven‐depleted osteosarcoma cells, while ATM, Chk2 and p53 activation remained intact. Osteosarcoma is notoriously difficult to treat with standard chemotherapy, and we examined whether pharmacological inhibition of the Aven‐controlled ATR–Chk1 response could sensitize osteosarcoma cells to genotoxic compounds. Indeed, pharmacological inhibitors targeting Chk1/Chk2 or those selective for Chk1 synergized with standard chemotherapy in 2D cultures. Likewise, in 3D extracellular matrix‐embedded cultures, Chk1 inhibition led to effective sensitization to chemotherapy. Together, these findings implicate Aven in ATR–Chk1 signalling and point towards Chk1 inhibition as a strategy to sensitize human osteosarcomas to chemotherapy. Copyright © 2015 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. 相似文献
35.
目的:探索可早期预测严重败血症病人死亡的临床和实验室指标或系统模型。方法:对ICU连续收治的26例严重败血症病人行前瞻性观察28天,分析其死亡的相关临床和实验室指标。结果:共有14人(54%)死亡,多死于第1周内(74%)。根据循环中的细胞间粘附分子-1水平能早期预测其脏器衰竭和死亡。一些临床指标水平在死亡病人与生存病人之间差别较大,其中包括血总胆红素、pH值、红细胞压积、氧合指数、动静脉血氧差、四项SIRS指标和一些血流动力学指标等。结论:综合上述指标可以尝试建立起了一个能够早期评估病人死亡可能性的积分系统。 相似文献
36.
上海中心城区幽门螺杆菌菌株原发性耐药的调查 总被引:1,自引:1,他引:1
背景:在全球范围内幽门螺杆菌(H.pylori)菌株对甲硝唑、克拉霉素和阿莫西林耐药的发生率正在不断增加。目的:了解H.pylori对甲硝唑、克拉霉素和阿莫西林的原发耐药情况。方法:2005年12月~2006年6月间因消化不良来上海市静安区中心医院行胃镜检查,除外大环内酯类、青霉素类抗生素和甲硝唑服药史,并经尿素酶试验初步确认H.pylori感染的患者.取其胃黏膜活检标本行体外微需氧培养,经生化、涂片检查鉴定为典型的H.pylori.经转代选择其中生长发育良好的菌株36株。应用E-test试纸测定其对甲硝唑、克拉霉素和阿莫西林的敏感性。结果:36株H.pylori菌株中,对甲硝唑、克拉霉素和阿莫西林的原发性耐药率分别为44-4%、8.3%和2.8%:甲硝唑耐药菌株分布与性别、年龄以及所患的胃十二指肠疾病种类无明显相关性。结论:有必要定期检测或调查本地H.pylori对抗生素的敏感性,以监测在根除H.pylori时应用“检测和治疗”策略的效果,提高根除H.pylori的疗效。 相似文献
37.
背景和目的:最近的研究结果表明,对其他一线药物和注射类药物(如卡那霉素、卷曲霉素)等耐药是影响耐多药结核病(MDR-TB)患者治疗效果的独立危险因素.本研究旨在明确耐其他一线药物和注射类药物对韩国不合并人免疫缺陷病毒(HIV)感染的MDR-TB患者临床疗效的影响.方法:采用回顾性队列研究分析1996年1月至2005年12月首尔国家大学附属医院治疗的211例MDR-TB患者治疗效果,排除7例丢失和7例迁出,对197例患者进行了最终分析. 相似文献
38.
Cisplatin is a platinum-based compound that is largely employed as an effective antitumor drug against a wide spectrum of solid neoplasms for many years. Despite of its initial therapeutic success, cisplatin often results in high incidence of chemoresistance and high-dose cytotoxicity. Consequently, considerable efforts in hopes of reducing the dose-dependent side effects of cisplatin while retaining, or even enhancing, its antitumor properties have been undertaken throughout the past three decades. Nitric oxide (NO) is a small lipophilic free radical gas possessing versatile biological functions, including antitumor activities. However, NO, of itself, is difficult to be used, because of its extreme instability and short half-life. Previously, we have reported a stable NO donor, β-galactosyl-pyrrolidinyl diazeniumdiolate (β-Gal-NONOate), which exerts tumor killing effects through site-specific intracellular release of exogenous NO. In this study, we further investigated the combined inhibitory effect of β-Gal-NONOate and cisplatin against C6/LacZ, 9L/LacZ, and HeLa/LacZ tumor cells. It was shown that, in combination with β-Gal-NONOate, the antitumor effects of cisplatin against these common tumor cell lines were increased in a dose-dependent manner. Furthermore, the combination of these chemicals resulted in a synergistic suppression on tumor growth, which was achieved under a much lower cisplatin dosage. Collectively, our findings indicate that β-Gal-NONOate can synergistically improve the antitumor effect of cisplatin, and may therefore reduce its side effects caused by high dose cisplatin monochemotherapies. Accordingly, β-Gal-NONOate is an important therapeutic assistant reagent with great potential of clinical applicability, and thus worth of continuous research in the coming future. 相似文献
39.
HJ Maas M Danhof & OE Della Pasqua 《Cephalalgia : an international journal of headache》2009,29(7):772-780
In migraine, headache severity varies with age. As a consequence, the effectiveness of medication may also depend on a patient's age. The purpose of this study was to assess the combined effect of age and drug treatment on headache characteristics. Using data from clinical trials of sumatriptan in adolescents and adults, we show how the interaction between age and drug exposure can be parameterised as a covariate on a Markov model that describes the decline of headache severity over three clinically defined stages (no relief, relief and pain-free status). The model explains important clinical observations: (i) the rates at which the pain relief and pain-free status were attained were found to be inversely related to age; (ii) in placebo-treated patients, the mean transit time from 'no relief' to 'relief' is 3 h for young adolescents and increases to 6 h for patients aged ≥ 30 years; and (iii) sumatriptan reduces the transit time to 2 h, irrespective of age. These findings indicate that the therapeutic gain over placebo increases with age. Prospective studies of antimigraine drugs should take this relationship into account when extrapolating efficacy data from adults to adolescents. 相似文献
40.