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41.
Lonidamine enhances the cytotoxicity in vitro of several conventional antitumor drugs as well as that of hyperthermia (HT). We have investigated the possibility that such enhancement can also be demonstrated in vivo against the RIF-1 tumor system. Two assays were used to examine antitumor activity: tumor growth delay and clonogenicity of cells obtained from tumors from treated animals. We used drug (and HT) doses that by themselves did not achieve significant cell killing. The drugs whose interaction with lonidamine was tested were: cis-diamminedichloroplatinum (CDDP), mitomycin C (MMC), bleomycin, 5-fluorouracil, and nitrosourea. Of these only CDDP and MMC yielded positive data. Both assays gave essentially the same results, showing that antitumor activity reflected direct cell killing. CDDP and MCC activity was also enhanced by HT. When we combined all three modalities, however, the results of the trimodality therapies were no better than that of individual bimodality treatments. These last results suggest that lonidamine and HT have similar mechanisms, most likely inhibition of repair of DNA damage. Our data do suggest that lonidamine may have a role in multidrug therapies that include either CDDP or MMC as a component of the treatments. 相似文献
42.
Tony M. Keaveny Tania P. Pinilla R. Paul Crawford David L. Kopperdahl Albert Lou 《Journal of orthopaedic research》1997,15(1):101-110
We sought to quantify the systematic and random errors associated with-artifacts in the platens compression test for trabecular bone. Our hypothesis was that while errors may depend on anatomic site, they do not depend on apparent density and therefore have substantial random components. Trabecular bone specimens were first tested nondestructively using newly developed accurate protocols and then were tested again using the platens compression test. Percentage differences in modulus between the techniques (bovine) proximal tibia [n = 18] and humerus [n = 17] and human lumbar spine, [n = 9] were in the range of 4-86%. These differences did not depend on anatomic site (p = 0.21) and were only weakly dependent on apparent density and specimen aspect ratio (r2 < 0.10). The mean percentage difference in modulus was 32.6% representing the systematic component of the end-artifact error. Neglecting the minor variations explained by density and specimen size (approximately 10%), an upper bound on the random error from end-artifacts in this experiment was taken as the SD of the modulus difference (±18.2%). Based on a synthesis of data taken from this study and from the literature, we concluded that the systematic underestimation error in the platens compression test can be only approximated and is in the range of 20-40%; the substantial random error (±12.5%) confounds correction, particularly when the sample size is small. These errors should be considered when interpreting results from the platens test, and more accurate testing techniques should be used when such errors are not acceptable. 相似文献
43.
应用对应于Dystrophin基因缺失热区的二对PCR引物和一对内对照无关引物,在同一反应体系中扩增,检测66例DMD/BMD患者。发现其中25例存在17号或49号外显子缺失,与同时采用cDNA探针杂交检测出的35例基因缺失相比.检出率达71.4%。说明该扩增系统能够作为快速筛查缺失型DMD/BMD患者的有效手段。这对指导合理选用探针,尤其在产前诊断方面,具有重要意义。 相似文献
44.
山东产四种菟丝子免疫增强作用的比较研究 总被引:14,自引:0,他引:14
目的 比较山东产四种菟丝子对小鼠免疫功能、抗疲劳、耐缺氧等方面的作用。方法 选用昆明种小鼠,用山东产四种菟丝子的水、醇提取物灌胃,观察小鼠腹腔巨噬细胞吞噬功能、免疫器官重量的变化、游泳实验和耐缺氧等指标。结果 山东产四种菟丝子均可增加小鼠吞噬百分率,使幼龄小鼠的胸腺和脾脏增重,并可显著延长小鼠的游泳及缺氧存活时间。其中以菟丝子和南方菟丝子的作用较好,水提取物的作用优于醇提取物。结论 山东产四种菟丝子具有增强机体免疫功能、抗疲劳、耐缺氧作用。菟丝子中的多糖是其提高机体免疫力,增强体质的有效物质之一。 相似文献
45.
Yan Wang Xuesong Zhang Songhua Xiao Ning Lu Zheng Wang Mi Zhou 《Journal of orthopaedic surgery and research》2006,1(1):13-7
Objectives
To investigate clinical effects and manual operational point of Bryan cervical disc prosthesis in Chinese, to observe the stability and range of movement (ROM) post-operatively. 相似文献46.
浅析《内经》之闭经证治 总被引:1,自引:1,他引:0
收集了《内经》有关闭经方面的相关阐述从而探讨闭经的病因病机、诊断与治疗,并详细记述了《内经》对血滞经闭和血枯经闭这两类型经闭的不同治疗法度。 相似文献
47.
P H Brown J Lenney S Armstrong A C Ning G K Crompton 《The European respiratory journal》1992,5(9):1143-1145
An open, randomized, cross-over study was performed to compare the efficacy and acceptability of two breath-actuated inhalers, the Turbohaler (T) and Diskhaler (D), for delivery of beta-agonists. Thirty six adults with chronic asthma requiring beta-agonists four times daily were treated with terbutaline 500 micrograms via T and salbutamol 400 micrograms via D four times daily, each period lasting four weeks. Additional bronchodilator via pressurized aerosol was permitted as required. Peak expiratory flow (PEF) was recorded in the morning (before and after beta-agonist) and in the evening. The mean morning PEF was higher during the first two weeks using T (295 l.min-1) than whilst using D (281 l.min-1, p < 0.01), but this difference did not persist during the second two weeks and there were no differences in post-bronchodilator PEF or rescue beta-agonist use. After four weeks, > 90% of patients used both inhaler devices efficiently and they were equally acceptable in terms of ease of use and convenience to carry. The Diskhaler and Turbohaler achieve similar clinical efficacy for delivery of beta-agonists. 相似文献
48.
49.
VE缺乏组、1/3需要量组、需要量组、3倍需要量组、20倍需要量组的初断奶小鼠喂养8周后观察T淋巴细胞转化及M中诱导IL-1反应。结果表明,VE增强半合适、合适剂量ConA诱导的胸腺、脾脏T淋巴细胞转化,且半合适剂量诱导的反应高于合适剂量,VE增强合适剂量PHA诱导的脾T细胞反应,但不影响其诱导胸腺T细胞反应。VE还提高MΦ诱导IL-1生成。上述实验以缺乏组反应最弱,3倍量组反应最强,而20倍量组反有下降趋势。 相似文献
50.