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101.
Chemotherapy has, besides the beneficial effects, several adverse effects. Suppression of the immune system is one of the most important problems. Infections caused by encapsulated bacteria like Streptococcus pneumoniae are responsible for a major part of infectious problems during and after treatment. The splenic marginal zone is essential in the initiation of an immune response to encapsulated bacteria. In this study, we analysed the effects of three different cytostatic agents on humoral immune responses. We found a reduced, but detectable immune response capacity at two days after treatment although the marginal zone B cell population is severely reduced at this time point. Twenty-four days after cessation of treatment, the immune response capacity was largely restored although lymphoid compartments were still not completely restored at that time point. Apparently, the presence of only few marginal zone B cells is sufficient to evoke a rise in antibody titres and although antibody titre increases are low, even small rises are most likely clinically relevant.  相似文献   
102.
A Sprague-Dawley rat model with DS sarcoma transplanted in the thigh was used to compare transcatheter locoregional i.a. and systemic i.v. administration of 5-fluorouracil (FU) at 12 dose-rate schedules: 25, 50 and 100 mg/kg; bolus, 1, 5 and 24 h infusions. In experiment A tumor (62/67 animals) as well as liver and kidney (56/67 animals) were excised 1 h after a single bolus or 1 h infusion or at the end of 5 and 24 h infusions. (19)F-NMR spectroscopy at 11.7 T was used to quantitate FU and its metabolites in ca. 1 g of tissue at 4 degrees C. In experiment B analogous FU treatments were repeated for 5 days (rats 80+11 controls). Tumor volumes vs time, various blood parameters and survival times were recorded, and a log growth rate parameter log GR, a response index RI, and a toxicity index TI were calculated. The i.a. vs i.v. ratios for tumor concentrations of FU and total anabolites (F-Nucl) were >1 for nearly all treatments and increased with infusion time at the higher doses. F-Nucl in tumor correlated linearly with total fluorine concentration (Tot. F range 30-1100 nmol/g) over all treatments (r=0.92, slope=0.45, p<0.0001). For non-bolus i.v. treatments [FU+F-Nucl] decreased linearly with decreasing FU dose rate (r(2)=0.74, zero intercept), while i.a. treatments showed non-linear behavior. For non-bolus treatments the mean log GR per treatment group showed a negative correlation (r=-0.87) with log[F-Nucl]. The most effective non-toxic treatments were 25 mg/kg over 5 or 24 h; the i.a. route was superior to i.v. on the basis of [FU+F-Nucl], RI, the reduction in log GR, and Kaplan-Meier survival statistics. For liver and kidney Tot. F (>83% FU catabolites) reached ca. 3-4 and 6-7 micromol/g, respectively, at the highest dose rates for either route; F-Nucl were detected only for Tot. F>500 nmol/g and increased exponentially as Tot. F increased (toxic treatments). The concentrations of the main catabolite (alpha-fluoro-beta-alanine, FBAL) in tumor did not correlate with Tot. F but rather with FBAL levels in kidney (r=0.90, all treatments), indicating that uptake of liver-derived FBAL from the circulation is the major source of FBAL in tumor.  相似文献   
103.
本文旨在探讨盆腔恶性肿瘤的介入性治疗问题。对45例患有盆腔恶性肿瘤的患者,采用Seldinger法,经双侧股动脉插管,先端选择性导入对侧髂内动脉;或一侧导入肠系膜下动脉,另侧导入髂内动脉,留置导管12小时,使用突击剂量持续灌注化疗药物。并经手术、B超、CT、内窥镜及指检等方法进行化疗前后的对比观察。结果:其中病灶消失持续1个月以上者9例、病灶缩小50%以上并持续超过一个月者23例、缩小不足50%且增大未达25%者9例、增大超过25%以上者4例,总有效率为71.1%。10例患者出现了脱发及皮肤色素沉着,1例患者出现下肢动脉栓塞,10例出现了不同程度的消化道反应等。结论:本法损伤小,操作简便安全,可多次重复术式:选择性强,药效持久均衡且毒副作用小;可提高手术切除率,也为不能手术的癌肿提供一种较理想的治疗手段。  相似文献   
104.
Summary In our wide experience of treating advanced breast carcinoma with chemotherapy, the combination of doxorubicin (DOX), vincristine (VCR), cyclophosphamide (CPM) and fluorouracil (FU) gave a complete plus partial response rate of over 60%, with 100% alopecia and frequent cardiac toxicity depending on total dose.After the EORTC Clinical Screening Group phase II trial we have conducted an expected difference method comparative phase II trial using the combination DOX, VCR, CPM, FU and the combination of MTX (10mg/m2), VCR, CPM and FU on a population of 50 breast carcinoma patients similar to those taking part in the first study.The reasons for similarity of action will be presented and discussed.  相似文献   
105.
A factor of nominal molecular weight 6K–10K Daltons, isolated from bovine aorta, has previously been shown to inhibit neovascularization and tumor growth in vivo and the growth of some tumor cells as well as endothelial cells in culture. This factor, termed A-10, was tested alone and in combination with Adriamycin against TA3Ha mammary adenocarcinoma cells in tissue culture. It was found to have cytotoxicity additive to that of Adriamycin in inhibiting the growth of these cells. In vitro and animal studies show that the sequence of Adriamycin A-10 is superior to either agent alone in delaying the appearance of palpable tumors after subcutaneous injection of 105 pre-treated tumor cells in the tail of strain A mice. While the growth rate of the primary tumor was not affected by such treatment, survival was prolonged to a greater degree by the this sequence than by either of these agents used alone. A-10 treatment reduced the number of metastases to the adrenal gland but not to lung, liver, or lymph nodes. It did, however, reduce the size of metastases to para-aortic lymph nodes.  相似文献   
106.
Summary Tumour growth essentially requires fibrin formation and fibrinopeptide A (FPA) is liberated into the circulation on fibrin formation. In the present study, a possible elevation of serum FPA level was examined in patients with metastatic brain tumour. A significant elevation of serum FPA level was shown in all 6 patients with metastatic brain tumour, when blood was drawn from the internal jugular vein. It was extremely high in 2 patients with rapidly growing tumour. However, such a significant elevation was not shown in 3 cancer patients without brain metastasis or in 1 patient with a huge meningioma. This suggests the possibility that the presence of metastatic brain tumour could be detected by measuring FPA in blood drawn form the internal jugular vein. This also suggests the tendency that elevation of serum FPA is higher in patients with more rapidly growing tumour.Infusion of urokinase into the internal carotid artery resulted in an elevation of serum fibrinopeptide B (1)15–42 (FPB) in 5 patients with metastatic brain tumour, when blood was drawn from the internal jugular vein. This suggests that urokinase could induce fibrinolysis in the tumour tissue, though this remains in conclusive because of the lack of complete controls.  相似文献   
107.
Selective effects of Lipiodolized antitumor agents   总被引:4,自引:0,他引:4  
Lipiodol Ultra-Fluid (Lipiodol) remains selectively in the tumor for an extended time when applied through arteries feeding the tumor. Although lipophilic antitumor drugs are selective when combined with Lipiodol, wide application of common hydrophilic agents is limited, as these compounds are insoluble in oil. We propose "Lipiodolization" of water-soluble agents using as an intermediate Urografin, a water-soluble contrast medium. Thirteen patients with primary hepatocellular carcinoma were treated with this Lipiodol-Urografin system containing antitumor agents. Marked decrease in serum alpha-fetoprotein (AFP) levels, decrease in tumor size in the hepatic imaging, and histologic studies of the resected specimen revealed this mode of therapy to be effective in 10 of 13 patients (77%) with hepatocellular carcinoma. Lipiodolization of antitumor agents is a new approach to selective cancer chemotherapy.  相似文献   
108.
 目的 构建基于少数类样本合成过抽样技术(synthetic minority over-sampling technique,SMOTE)算法的化学治疗(化疗)肿瘤患者下呼吸道感染预警模型。方法 共纳入西宁市4所三级医院2019年1月-2021年6月收治的2 384例接受化疗的肿瘤患者为研究对象,将所收集病例按照7:3的比例随机分为建模组1 668例和验证组716例,建模组数据用来建立模型,验证组数据对所建立的模型进行验证,利用单因素比较和logistic回归分析筛选下呼吸道感染影响因素,基于SMOTE算法建立化疗肿瘤患者下呼吸道感染预警模型。结果 logistic回归分析可得,年龄(x1)、身体质量指数(BMI)值是否正常(x2)、恶性肿瘤分期(x3)、吸烟史(x4)、合并糖尿病(x5)、合并肺部疾病(x6)均是化疗肿瘤患者下呼吸道感染的危险因素(均P<0.01),获得原始数据预警模型:Logit(P)=0.055x1+0.967x2-0.195x3+1.383x4+0.968x5+0.939x6-14.073和基于SMOTE算法的预警模型:Logit(P)=0.090x1+1.092x2-0.249x3+1.724x4+1.136x5+1.344x6-14.859。基于SMOTE算法预警模型AUC为0.949(95%CI:0.937~0.961),高于原始数据预警模型AUC 0.780(95%CI:0.734~0.846)。结论 基于SMOTE算法所构建的预警模型能更准确预警化疗肿瘤患者下呼吸道感染,有效解决感染与非感染患者样本数据不平衡所导致的预测误差,基于预测模型可选择相应的对策进行应对。  相似文献   
109.
目的:观察BT-BAK细胞与BCG膀胱腔内灌注治疗对患者全身免疫功能的影响。方法:由手术切除的膀胱瘤标本制备膀胱肿瘤可溶性抗原,以BCG为佐剂,从PBMNC中诱导出抗膀胱肿瘤特异性细胞毒性BT-BAK细胞,临床选择72例浅表性膀胱癌术后患者随机平均分成2组分别进行BT-BAK和BCG的膀胱腔内灌注治疗。于不同阶段采用ELISA法测定患者外周血中IL-2、TNF-α及IFN-γ的含量;观察治疗后患者PBMNC对T24膀胱肿瘤细胞株杀伤活性的变化。结果:BT-BAK组患者血清中IL-2、TNF-α及IFN-γ的水平均较治疗前明显提高(P<0.01);患者PBMNC对T24膀胱肿瘤细胞株的杀伤活性显著增强(P<0.01)。BT-BAK组上述指标均高于BCG组(P<0.05)。平均随访18.16个月,两组的复发率分别为2.7%和11.11%。结论:BT-BAK细胞及其培养上清进行膀胱腔内灌注治疗,能够有效提高膀胱癌术后患者的全身免疫水平,降低膀胱癌的术后复发率。  相似文献   
110.
目的观察髂内动脉灌注化疗联合手术治疗膀胱癌的疗效。方法对32例中晚期膀胱癌先行介入治疗,再手术切除。结果32例膀胱癌完全缓解(CR)率为71.9%。结论介入治疗中晚期膀胱的手术提供了良好基础,对一部分原本行扩大切除术甚至全切的患实行单纯部分切除术,从而保留了膀胱生理功能,有助于提高患生活质量,延长生命。  相似文献   
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