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41.
The pharmacokinetics and pharmacodynamics of prolonged oral etoposide chemotherapy were investigated in 15 women with metastatic breast cancer who received oral etoposide 100 mg as a single daily dose for up to 15 days. There was considerable interpatient variability in the day 1 pharmacokinetic parameters: area under the plasma concentration time curve (AUC) (0–24 h) 1.95±0.87 mg/ml per min (mean ± SD), apparent oral clearance 60.9±21.7 ml/min per 1.73 m2, peak plasma concentration 5.6±2.5 g/ml, time to peak concentration 73±35 min and half-life 220±83 min. However, intrapatient variability in systemic exposure to etoposide was much less with repeated doses. The intrapatient coefficient of variation (CV) of AUC for day 8 relative to day 1 was 20% and for day 15 relative to day 1 was 15%, compared to the day 1 interpatient CV of 45%. Neutropenia was the principal toxicity. Day 1 pharmacokinetic parameters were related to the percentage decrease in absolute neutrophil count using the sigmoidal Emax equation. A good fit was found between day 1 AUC and neutrophil toxicity (R 2=0.77). All patients who had a day 1 AUC>2.0 mg/ml per min had WHO grade III or IV neutropenia. The predictive performance of the models for neutrophil toxicity was better for AUC (percentage mean predictive error 5%, percentage root mean square error 18.1%) than apparent oral clearance, peak plasma concentration, or daily dose (mg/m2). A limited sampling strategy was developed to predict AUC using a linear regression model incorporating a patient effect. Data sets were divided into training and test sets. The AUC could be estimated using a model utilizing plasma etoposide concentration at only two time points, 4 h and 6 h after oral dosing (R 2=98.9%). The equation AUCpr=–0.376+0.631×C4h+0.336×C6h was validated on the test set with a relative mean predictive error of –0.88% and relative root mean square error of 6.4%. These results suggest monitoring of AUC to predict subsequent myelosuppression as a strategy for future trials with oral etoposide.Division of Haematology and Medical Oncology, Peter MacCallum Cancer Institute, Locked Bag 1, A'Beckett St, Melbourne 3000, Australia  相似文献   
42.
We demonstrate here that motoneurons and nigral dopaminergic neurons in the brainstem of the adult rat, with the exception of motoneurons innervating ocular muscles, display high levels of both MHC class I heavy chain and beta2-microglobulin mRNAs. These neurons also display interferon-gamma receptor mRNA. We find it striking that these particular neurons are those which are vulnerable to neurodegeneration in diseases such as Parkinson's disease (PD) and amyotrophic lateral sclerosis (ALS).  相似文献   
43.
The article describes the development of symptoms in a 59-year-old patient. Dyskinesia and speech disorder were the only clinical features in the beginning. Increased immunological parameters and only slight hypokinetic-rigid signs for a long time made the diagnostical and therapeutical process more difficult, as well as atypical findings in neuroimaging techniques. Corticobasal degeneration was diagnosed about 6 years after onset of clinical symptoms.  相似文献   
44.
BACKGROUND: To assess antitumor activity and toxicity of pemetrexed in metastatic breast cancer (MBC) patients previously treated with anthracyclines. PATIENTS AND METHODS: Seventy-seven MBC patients from 12 European institutions were entered into the study. Seventy-two patients were considered evaluable for response and toxicity. Forty-two patients were classified as anthracycline-failure (relapse >30 days after completion of a prior anthracycline regimen) and 30 as anthracycline-refractory (progression within 30 days after anthracycline therapy). Pemetrexed 600 mg/m(2) was administered intravenously every 3 weeks until progressive disease or unacceptable toxicity. RESULTS: There were three complete and 12 partial responders [response rate 21% (95% confidence interval 12%)]. Response rates in the anthracycline-failure and anthracycline-refractory groups were 24% and 17%, respectively. A subset of 31 patients pretreated with anthracyclines and taxanes had a response rate of 26%. Median duration of response and median survival were 5.5 and 10.7 months, respectively (13 months in the failure group and 5.7 months for refractory). Grade 3/4 toxicities included neutropenia and thrombocytopenia in 56% and 19% of patients, respectively. Nine patients (12%) experienced neutropenic fever. Grade 3/4 non-hematological toxicities included skin rash (10%), nausea (12%), fatigue (10%) and stomatitis (5%). CONCLUSION: Our trial demonstrates pemetrexed to be active in breast cancer, with manageable toxicity. Activity of pemetrexed did not appear to be adversely affected by prior taxane, 5-fluorouracil or endocrine treatments.  相似文献   
45.
The aim of this study was to study pulmonary radiological abnormalities with chest radiography following different radiotherapy (RT) techniques for breast cancer with respect to regions and density, and their association with pulmonary complications and reduction in vital capacity (VC). Chest radiographs were performed 5 months following local or loco-regional RT in 167 breast cancer patients. The radiological abnormalities were analysed with a classification system originally proposed by Arriagada and evaluated according to increasing density (0–3) and affected lung regions (apical–lateral, basal–lateral, central–parahilar). The highest-density grades in each region were added together to form scores ranging from 0 to 9. The patients were monitored for RT-induced pulmonary complications. The VC was measured prior to and 5 months following RT. An independent evaluation of 51 patients was performed by a second radiologist to control the reproducibility of the classification system. Increasing scores were associated with loco-regional RT and pulmonary complications (P < 0.001). The mean reduction of VC for patients scoring 0–3 (–30 ml) vs 4–9 (–161 ml) was not statistically significant (P = 0.10). Scores of 4–9 were more frequently observed in older patients (P < 0.001). The independent evaluations by two radiologists revealed good agreement (P < 0.001) and no systematic inter-observer variation. Radiological abnormalities on chest radiographs, scored according to Arriagada, can be used as an objective end point for RT-induced pulmonary side effects in breast cancer. Received: 4 February 1999; Revision received: 1 April 1999; Accepted: 5 May 1999  相似文献   
46.
脂蛋白脂肪酶基因突变的研究   总被引:4,自引:2,他引:4  
目的:筛查国人脂蛋白脂肪酶(LPL)基因的突变,并探讨其与高甘油三酯血症的关系。方法:对高甘油三酯血症组(48例)和正常甘油三酯对照组(121例)的各扩增片段进行分析,电泳图谱异常者进行PCR产物测序。对于频率较高的多态性位点,引入限制性核酸内切酶位点利用PCR-RFLP进行鉴定。结果:在高甘油三酯血症人群中,检出2例内含子3受位剪接点上游6bp的C→T转换的突变杂合子,1例外显子5Pm^207→Leu突变杂合子,在全部样品中检出1例Ser^447→stop突变纯合子,50例Ser^447→stop杂合子。结论:天津地区人群中存在着LPL基因突变,除Ser^447→stop外,内含子3和外显子5的突变多与高甘油三酯血症相关,可能是高甘油三酯血症的遗传易感因子。  相似文献   
47.
目的观察氧化亚氮混合气体在分娩过程中的作用,分析其分娩结局.方法选择临床自愿吸入氧化亚氮混合气体无痛分娩的第1胎头位的初产妇135例为观察组,随机抽取同期分娩的产妇190例为对照组,观察其分娩过程及结局.结果无痛分娩组产妇紧张、焦虑及疼痛程度较对照组明显降低,剖宫产率明显降低(P<0.05),两组总产程、新生儿评分及产后出血量无统计学意义.结论氧化亚氮混合气体无痛分娩法方便、安全、有效,值得临床推广应用.  相似文献   
48.
将岩虫匀浆液经反相浓缩、凝胶过滤和亲和柱层析获得活性组分,在体外用MTS/PMS(氮兰四唑盐/吩嗪硫酸甲酯)方法筛选抗菌肽,再分别用MTS/PMS方法和ELISA—AFP(甲胎蛋白)方法检测其对人肝癌细胞株HepG2增殖、AFP分泌及对正常大鼠成骨细胞株MC3T3-E1增殖的影响。结果表明,纯化的岩虫抗菌肽为组成型碱性蛋白(MW8.1kDa,pI8.6),不同浓度抗菌肽对肝癌细胞增殖和AFP的分泌均有抑制作用,抑制作用大小与抗菌肽浓度呈正相关性;对正常成骨细胞未见明显的抑制和杀伤作用。  相似文献   
49.
河北省部分高校大学生结核菌素试验结果分析   总被引:3,自引:0,他引:3  
目的了解结核菌在大学生群体中的感染状况及PPD试验过程中存在的问题,为采取相应的干预措施提供依据。方法随机抽取河北省8所高校,对其在2001~2004年新入学大学生的PPD试验记录及监测报表进行统计分析。结果河北省部分高校大学生接种人口数量明显增多;经χ2检验,2001~2004年PPD试验的阳性率、强阳性率差异有统计学意义(P<0.005),阳性率随时间呈明显下降趋势、强阳性率随时间呈缓慢上升趋势。结论高校应进一步加强PPD试验的监测力度,提高PPD的监测质量。  相似文献   
50.
Primary cardiac hemangioendothelioma is extremely rare.1-3 Up to now less than twenty cases have been reported in English literature, the data about this kind of cardiac tumors are scanty. In this report, a case of a huge hemangio-endothelioma that arose from the right atrium and was successfully resected is presented.  相似文献   
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