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11.
Some effects of urease administration on laboratory animals   总被引:2,自引:0,他引:2  
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似昼夜节律与学习效应对脑事件相关电位P300的影响   总被引:1,自引:0,他引:1  
付兆君  马瑞山 《医学争鸣》2001,22(2):110-112
目的 探讨昼夜节律和学习效应对脑事件相关电位P300成分的影响。方法 8名被试者在非连续的5d的实验中每天在5个时间点(7:00,12:00,16:00,20:00和0:00)重复相同的听觉Oddball模式测试以诱发脑事件相关电位(ERP)。然后测量各次的ERPP300成分,得到其潜伏期及波幅。结果 P300波幅明显高于下午的波辐。重复测量也使P300波幅从第1个实验日的平均13.0uV降至第5个实验日的9.2uV。P300潜伏期随着重复测试的增加出现了习服,它从第2个实验日的平均350.6ms缩短为第5个实验日的平均343.5ms.结论 似昼夜节律和学习效应对脑事件相关电位P300成分的波幅和潜伏期均有影响。  相似文献   
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采用反相高效液相色谱蒸发激光散射检测器测定三七中人参皂苷Rg1的含量。色谱柱为CLC-ODS(6.0mm×150mm),流动相为乙腈-水(3070),蒸发激光散射检测器。定量方法简单,准确。回收率为100.50%,RSD为1.82%。并用紫外分光光度法测定了三七中总皂苷的含量,结果和HPLC法基本一致,说明该方法定量准确,回收率为101.50%,RSD为1.44%。结论认为两方法均可以控制三七的质量。  相似文献   
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Residues energetically linked to the allosteric transition of thrombin from its anticoagulant slow form to the procoagulant fast form have been identified by site-directed mutagenesis. The energetics of recognition by the two forms of the enzyme were probed by using a synthetic chromogenic substrate, fibrinogen, and hirudin. The thrombin residues E39, W60d, E192, D221, and D222 are linked to the slow-->fast transition and are part of an "allosteric core" through which events originating at the Na+ binding loop propagate to other regions of the enzyme. The thrombin residues Y76, W96, W148, and R173 lie at the periphery of the allosteric core, affect recognition of fibrinogen and hirudin to the same extent in both forms, and are not linked to the slow-->fast transition.  相似文献   
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PURPOSE: Denileukin diftitox is a fusion protein combining diphtheria toxin and interleukin-2 (IL-2) that targets tumor cells expressing the IL-2 receptor. Its efficacy has been shown in CD25+ cutaneous T-cell lymphoma, but not in B-cell non-Hodgkin's lymphoma (NHL). A phase II study was performed to evaluate the efficacy and tolerability of denileukin diftitox for relapsed or refractory B-cell NHL. PATIENTS AND METHODS: Patients with relapsed or refractory B-cell NHL were eligible. Tumor CD25 expression was determined by immunohistochemistry or flow cytometry. Denileukin diftitox was administered intravenously at a dose of 18 microg/kg once daily for 5 days every 3 weeks, up to eight cycles. RESULTS: Of the 45 patients assessable for response, 32 (71%) were refractory to the last chemotherapy treatment, and all were previously treated with rituximab. Three complete responses (6.7%) and eight partial responses (17.8%) were observed, for an overall response rate of 24.5%. Nine patients (20%) had stable disease. Objective response rates were similar in CD25+ (22%) and CD25- histologies (29%), as were stable disease rates (22% and 18%, respectively). For responding patients, the median time to treatment failure was 7 months, with a median follow-up in survivors of 18 months (range, 9 to 28 months), and the projected progression-free survival at 20 months was 24% (95% CI, 0% to 60%). Most toxicities were low-grade and transient. CONCLUSION: Denileukin diftitox seems to be effective in relapsed or refractory, CD25+ and CD25- B-cell NHL and is well-tolerated at the dosage evaluated. Evaluation of denileukin diftitox in combination with other agents may be warranted.  相似文献   
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为探讨肺癌脊柱转移放射治疗的时间剂量分割方法及其疗效,将肺癌脊柱转移64例患者随机分为治疗组和对照组,治疗组每次3Gy,每周5次,共30Gy;对照组每次2Gy,每周5次,共50Gy;两组均使用6mVX线照射.分别比较疼痛缓解率、止痛起效时间、及脊髓压迫缓解率.结果显示治疗组和对照组的疼痛缓解率分别为87.5%和81.3%,无显著性差异(P>0.05);平均止痛起效时间分别为8±2.2天和15±3.2天,差异性显著(P<0.01);脊髓压迫缓解率分别为85.0%和81.8%,无显著性差异(P>0.05).结果表明放射治疗肺癌脊柱转移疗效好,起效快,建议使用30Gy/10f/2W的时间剂量分割模式.  相似文献   
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ObjectiveTo evaluate the effect of different levels of physician experience on the high-intensity focused ultrasound (HIFU) ablation of uterine fibroids and to provide a reference for the use of non-perfused volume ratio (NPVR) standards during training.MethodsThis prospective multicentre study enrolled patients with uterine fibroids. The effect of the physician’s level of experience on the outcomes under different NPVR standards and the learning curve of six centres without HIFU experience were analysed. The impact of patient demographic and clinical characteristics were also evaluated.ResultsA total of 1352 patients from 20 centres were included in the study. The median NPVRs were 92.00%, 88.10% and 92.86% in the no experience group, inexperienced group and experienced group, respectively. Posterior wall fibroids, lateral wall fibroids and fundus fibroids were inversely correlated with NPVR, while experienced physicians were positively correlated with NPVR. With NPVR ≥ 70% and NPVR ≥ 80% standards, physicians in the no experience group completed the learning curve on the 11th and 16th procedure, respectively. Physicians under a standard of an NPVR ≥ 90% did not complete the learning curve.ConclusionsNPVR ≥ 80% is a standard that is worth using for HIFU treatment of uterine fibroids.  相似文献   
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In this study, we aimed to evaluate the effect of Nobiletin (NOB) on the placenta of Sprague–Dawley (SD) rats that had undergone reduced uterine perfusion pressure (RUPP) surgery and to evaluate the safety of NOB intervention during pregnancy. The results showed that NOB alleviated placental hypoxia, attenuated placental cell apoptosis, and inhibited placental damage in RUPP rats. No side effect of NOB intervention during pregnancy was observed. BeWo cell lines with P53 knockdown were then constructed using lentiviral transfection, and the P53 signaling pathway was found to be essential for NOB to reduce hypoxia-induced apoptosis of the BeWo cell lines. In summary, NOB attenuated hypoxia-induced placental damage by regulating the P53 signaling pathway, and those findings may contribute some insights into the role of NOB in placental development and the prevention of placental-related diseases.  相似文献   
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