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101.
Introduction: Suramin is a synthetic polysulfonated naphthylurea which has been used for the treatment of African trypanosomiasis and onchocerciasis, but since the mid-1980s has received attention as a possible antiretroviral and antineoplastic agent. Objective: This clinical trial of suramin was undertaken as a phase I/II study in patients with hormone-refractory prostate cancer, with the hypothesis that the intensity of therapy with suramin could be increased significantly if measures were undertaken to maintain the plasma concentrations of the drug under 300 μg/ml. Methods: We report the clinical results of this trial, wherein patients were treated at three different targeted plasma suramin concentrations (275, 215 and 175 μg/ml) for varying periods of time (2, 4 or 8 weeks), with delivery of the drug by continuous intravenous infusion. Results: The major toxicity observed in this trial was neurologic, consisting of a motor and sensory peripheral neuropathy that resulted in both paresis and paralysis of the limbs. Nearly all of this severe (CTEP grade III, IV) neurologic toxicity was observed in the patients treated at a plasma suramin concentration of 275 μg/ml for 4 or more weeks. A single patient treated at 215 μg/ml for 8 weeks developed moderate (CTEP grade III) proximal lower extremity weakness, and no patient treated at 175 μg/ml developed this toxicity. The second most common toxicity observed was infection of the central venous catheter. The overall response rate for all of the evaluable patients was 17% (13 of 75 patients). In addition, prostate-specific antigen (PSA)-defined responses were observed in six patients receiving therapy at 175 μg/ml, but these responses were confounded by cessation of therapy with flutamide during suramin treatment. Conclusions: In summary, although plasma suramin concentrations were maintained below 300 μg/ml, neurologic toxicity nonetheless occurred with high frequency in patients treated at 275 μg/ml for 4 or more weeks. Therapy at 215 and 175 μg/ml was in general well tolerated, but central venous catheter-related infection, as well as the inconvenience and expense of continuous infusional therapy, make this method of drug delivery impractical. Only moderate antitumor activity was observed during this trial, but it is possible that both continuation of flutamide and flutamide withdrawal during suramin therapy confounded the assessment of suramin’s activity in hormone-refractory prostate cancer. Received: 9 June 1995/Accepted: 18 March 1996  相似文献   
102.
经逆转录病毒载体将人GM-CSF基因导入人膀胱癌细胞株BIU-87细胞中,建立了转基因细胞株BIU/GM。经流式细胞仪行细胞DNA周期分析表明GM-CSF基因的导人及表达对BIU-87细胞的增长无影响。免疫荧光测定发现转GM-CSF基因及表达不能促进BIU-87细胞表面HLA-ABC、DR、DQ抗原的表达。转基因瘤细胞株经6000rad X射线照射灭活后,丧失增殖能力,逐步死亡,但能维持一定水平的GM-CSF分泌活性达两周以上。从而为制备灭活的转基因瘤苗提供了初步经验。  相似文献   
103.
A study to explore the role of a community oncology nurse specialist   总被引:1,自引:0,他引:1  
Cancer patients are increasingly being cared for in the community. However, the role of the community oncology nurse specialist (CONS) remains a rare appointment in the United Kingdom. There is little research evidence to substantiate the view that this is a worthwhile and effective role. This study aimed to explore the role of one CONS using a qualitative case study approach. The sample consisted of the CONS, seven patients, no relatives and five community nurses. Semi-structured interviews were used to elicit the view of these participants. In addition, documents containing details of the CONS's work to date were reviewed. A number of the CONS's role components were identified by the different respondent groups. Five themes were identified within the data collected: functions of the CONS, communication between the CONS and other health care professionals, structural and organizational factors, characteristics of the service and benefits to patients and their families. Furthermore, all respondent groups were positive about the service offered by the CONS, and felt that the role was valuable. Some negative features were identified and these were concerned with organizational aspects of the service. The findings suggest the need for further research and evaluation in this area.  相似文献   
104.
胃癌病人天然杀伤细胞活性监测   总被引:2,自引:0,他引:2  
报道微量细胞毒试验——LDH 释放法用于对胃癌病人临床免疫的监测.测定100例正常人和50例胃癌病人外周血 NK 细胞毒.结果:正常人值为36.10±5.68,胃癌组中,10例早期胃癌为28.76±4.70,25例进展期胃癌为14.51±5.80,15例晚期胃癌为11.86±4.43,与正常人值比较,P 值分别>0.05,<0.01和<0.01.NK 细胞毒活性随胃癌病变的进展和肿瘤体积的增大而逐渐降低,手术切除肿瘤后可有不同程度回升,甚至恢复到正常水平。长期化疗能损伤 NK 活性.  相似文献   
105.
Proportionate cancer mortality was analyzed among white male carpet and textile workers in five northwest Georgia counties for the years 1970-1984. Compared with other Georgians, carpet and textile workers had higher proportions of lymphocytic leukemia (proportionate cancer mortality ratio [PCMR] = 2.9; 95% CI = 1.4-5.4]) and testicular cancer (PCMR = 3.2; 95% CI = 1.0-7.5). The excess mortality from lymphocytic leukemia was even higher when the analysis was limited to workers deemed most likely to work directly in production areas (PCMR = 4.2; 95% CI = 1.7-8.7). Further studies are needed to determine if the observed excesses are the result of workplace exposures.  相似文献   
106.
Treatment of non-seminomatous testicular cancer often leadsto infertility due to anejaculation/retrograde ejaculation andpoor sperm quality. In these men spermatozoa may be obtainedby transrectal electroejaculation (TE), but the optimal strategyfor assisted procreation in these couples is not known. Ouraim was to examine whether TE and conventional in-vitro fertilization(IVF) would be successful. A total of 10 couples, with long-standinginfertility due to anejaculation or retrograde ejaculation aftertreatment for testicular cancer 5–14 years earlier, werereferred to our unit. All men underwent diagnostic TE undergeneral anaesthesia. Spermatozoa were recovered in nine cases.The antegrade fraction was prepared and used for IVF. Spermquality was variable and conventional IVF was considered impossiblein three cases. Altogether six IVF treatment cycles in six couplesresulted in five pregnancies, of which four resulted in a deliveryand one resulted in a spontaneous abortion. One additional pregnancyis ongoing after transfer of cryopreserved embryos. The fertilizationrate was 54% (33/61) and the cleavage rate was 97% (32/33).No complications relating to the procedure have been encountered.  相似文献   
107.
Summary Thirty-two eligible patients with advanced metastatic breast cancer who had received no more than 1 prior chemotherapy regimen for metastatic disease (16 had received prior doxorubicin) were treated with piroxantrone at a dose of 120 mg/m2 intravenously every 21 days. In the twenty-seven patients evaluable for response, two partial responses were seen. Toxicities observed were primarily hematologic with grade 3 or greater granulocytopenia occurring in 34% of the patients. One patient developed symptomatic congestive heart failure at a total cumulative dose of 960 mg/m2. We conclude that piroxantrone given at this dose and schedule has minimal activity in patients with metastatic breast cancer.  相似文献   
108.
Summary Based upon the hypothesis that dipyridamole would potentiate the cytotoxicity of mitoxantrone and the combination of 5-fluorouracil (5-FU) and leukovorin, we performed a phase I/II trial of the combination of dipyridamole, 5-FU, leukovorin, and mitoxantrone in patients with metastatic breast cancer. The dose of dipyridamole was fixed at 175 mg/m2 by mouth every 6 h (700 mg/m2/day), based upon a previous phase I trial of oral dipyridamole with 5-FU and leukovorin. Dipyridamole therapy began 24 h prior to the first dose of chemotherapy and continued until 24 h after the last dose of chemotherapy for each course of treatment. At the initial dose level, leukovorin 200 mg/m2 was given intravenously immediately prior to 5-FU 375 mg/ m2 intravenously on days 1–5. Mitoxantrone 6 mg/m2 was given as a single dose on day 3. Unacceptable toxicity was observed at this dose level, leading to successive dose decrements rather than dose increments. The maximum tolerated dose was leukovorin 200 mg/m2 days 1–2, 5-FU 375 mg/m2 days 1–2, mitoxantrone 6 mg/m2 on day 2, and dipyridamole 175 mg/m2 every 6 h on days 0–3. Two responses were produced in 15 patients. This regimen is not recommended for further investigation in the treatment of breast cancer.  相似文献   
109.
Summary The present study provides information relevant to a number of variables which may influence response to treatment of nude mouse-grown human urothelial cancer. A number of xenotransplanted tumors were exposed to selected treatments at different transplant generations, and at various dose levels and treatment schedules. It was observed that nude mouse-grown tumors were characterized by consistency, reproducibility and biological stability not affected by the transplant generation at which they were examined. Treatment related dose response curves were steep, the sharpness of the curves depending on the degree of tumor sensitivity. Best therapeutic results were obtained at the maximum tolerated dose of cytotoxic agents under study and of importance, a 20% to 40% dose reduction with the same treatment schedule resulted in little or no activity. In addition, treatment schedule, timing and sequence of treatments and to a certain degree, tumor grade were important variables which could influence tumor response. The nude mouse-human tumor system provides important preclinical guidelines on dose, schedule, sequence and timing of treatments and can assist in designing more efficient clinical trials.  相似文献   
110.
目的 :介绍食管钡餐连续摄影用于诊断早期食管癌的初步临床应用。方法 :用德国产的数字化胃肠机检查并诊断了 6例早期食管癌病人。与常规食管双重对比造影类似 ,病人立位口服钡剂 ,同时进行连续摄影 ,速度为 2帧 s,持续约 10s。观察不同的时相 ,包括充盈相、黏膜相和双对比相。结果 :在 6例病人中可见食管功能的改变及黏膜皱襞的病变 ,用连续摄影诊断后经内镜及病理检查确诊。 4例病人有轻度扩张受限 ,2例病人有痉挛性收缩 ,1例有钡剂滞留。 6例病人中均可见增粗的或中断的黏膜。 5例病人可见小溃疡。结论 :食管钡餐连续摄影可提供更全面的信息。用此法更可提供食管功能性的改变。  相似文献   
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