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51.
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目的 :通过舌癌术前化疗增殖细胞核抗原 (PCNA )和细胞凋亡相关基因 bcl- 2、Bax表达的研究 ,探讨舌癌的化疗作用机制。 方法 :对舌乳头状瘤、舌癌和舌癌术前化疗标本共 34例 ,采用免疫组织化学染色技术——酶标链亲和素生物素法 (L SAB)染色并进行光镜下观察。结果:PCNA在舌癌中的表达最强 ,在舌癌术前化疗中的表达明显减弱 (P <0 .0 5 ) ,其与舌乳头状瘤表达相似 (P >0 .0 5 )。 bcl- 2在舌癌术前化疗及舌乳头状瘤中低表达(P >0 .0 5 ) ,舌癌中表达明显增强 (P <0 .0 5 )。Bax在舌癌组和乳头状瘤组中表达有明显差异 (P <0 .0 5 )。结论 :化疗药物抑制肿瘤生长的机制可能与抑制肿瘤细胞增殖和诱导肿瘤细胞程序性死亡有关 ,提示舌癌术前化疗对肿瘤的预后有重要意义。  相似文献   
53.
The aim of this study was to survey the present status and patterns of reirradiation (Re-RT) practice using external beam radiotherapy in Japan. We distributed an e-mail questionnaire to the Japanese Society for Radiation Oncology partner institutions, which consisted of part 1 (number of Re-RT cases in 2008–2012 and 2013–2018) and part 2 (indications and treatment planning for Re-RT and eight case scenarios). Of the 85 institutions that replied to part 1, 75 (88%) performed Re-RTs. However, 59 of these 75 institutions (79%) reported difficulty in obtaining Re-RT case information from their databases. The responses from 37 institutions included the number of Re-RT cases, which totaled 508 in the period from 2009 to 2013 (institution median 3; 0–235), and an increase to 762 cases in the period from 2014 to 2018 (12.5; 0–295). A total of 47 physicians responded to part 2 of the survey. Important indications for Re-RT that were considered were age, performance status, life expectancy, absence of distant metastases and time interval since previous radiotherapy. In addition to clinical decision-making factors, previous total radiation dose, volume of irradiated tissue and the biologically equivalent dose were considered during Re-RT planning. From the eight site-specific scenarios presented to the respondents, >60% of radiation oncologists agreed to perform Re-RT. Re-RT cases have increased in number, and interest in Re-RT among radiation oncologists has increased recently due to advances in technology. However, several problems exist that emphasize the need for consensus building and the establishment of guidelines for practice and prospective evaluation.  相似文献   
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Natural antibodies to cytokines can be found in the sera of normal healthy individuals in the absence of specific immunostimulation. However, the function, impact, and purpose of natural antibody development have yet to be fully elucidated. Interleukin (IL)-18 is a cytokine that exerts proinflammatory activities and induces natural killer (NK) cell activity. Recombinant human IL-18 (rHuIL-18) is currently in development as a cancer immunotherapy. In this study, the presence of natural antibodies to IL-18 in the sera of normal humans and three nonhuman primate species was evaluated by electrochemiluminescence immunoassay (ECLIA). Of the human sera tested, 6 of 47 samples were positive for natural antibodies to IL-18. Of the nonhuman primate sera tested, 22 of 80 cynomolgus monkey samples, 4 of 31 rhesus monkey samples, and 2 of 20 chimpanzee samples were positive for natural antibodies to IL-18. Natural anti-IL-18 antibodies were neutralizing in 5 of 22 cynomolgus and 2 of 4 rhesus sera. None of the chimpanzee or human sera were able to neutralize IL-18 induction of interferon (IFN)-gamma in vitro. In vivo activity of rHuIL-18 was compared in IL-18 natural antibody-positive and -negative cynomolgus monkeys. The presence of natural antibodies to IL-18 did not alter rHuIL-18 systemic exposure levels, induction of neopterin, or induction of treatment-induced antibodies following intravenous administration of rHuIL-18. In conclusion, our data indicate that, as has been found with other cytokines, natural anti-IL-18 antibodies are relatively common. Moreover, natural anti-IL-18 antibodies do not appear to influence rHuIL-18 activity in vivo and are not predictive of a heightened immune response, suggesting that natural anti-IL-18 antibodies do not impact IL-18 therapy. Finally, our data suggest that the ability to detect natural anti-cytokine antibodies may be a useful measure of the adequacy of an assay for deployment in clinical trials.  相似文献   
56.
Summary The cardiovascular effects at rest and during exercise and 1- and 2-adrenoceptor occupancy following a single dose of 1200 mg celiprolol p. o. were investigated in 8 healthy subjects with or without pretreatment with a single dose of 20 mg bisoprolol p. o., using a place-bo-controlled, 2-way cross-over design.The ergometric responses of heart rate (HR) and systolic blood pressure (SBP) after celiprolol were reduced to a similar extent as after bisoprolol, but the cardiovascular function at rest was affected in a different way: there was a rise in HR, clear enhancement of cardiac systolic performance, and a considerable drop in the estimated total peripheral vascular resistance, associated with median 1-RRA and 2-RRA occupancies of 88 and 34%, respectively. The cardiovascular effects of celiprolol were not affected by pretreatment with bisoprolol. Celiprolol thus binds extensively to 1-adrenoceptors, moderately to 2-adrenoceptors, acts as 1-adrenergic antagonist (exemplified by the ergometric effects) but has vasodilator, positive chronotropic and cardiac systolic performance enhancing properties, which do not involve either direct or indirect 1-adrenergic agonism, but which might reflect 2-adrenergic agonism.  相似文献   
57.
为建立一种检测活细胞数的方法,作者采用三磷酸腺苷(ATP)生物荧光液闪测定法检测小鼠纤维瘤细胞株L929.ATP标准曲线工作范围为10 -9~10-5mol/ml,相关系数r=0.9963(P<0.001);当活细胞数在3×1 02~106个/ml时与发光计数值有良好的线性关系,r=0.9922(P<0.001),变异系数 CV = 1%~3%.用ATP生物荧光液闪测定法检测活细胞数灵敏、简便、准确、重复性好,用液闪计数仪即可完成测定,有较大的实用价值.  相似文献   
58.
目的 研究俄歇电子发射体67Ga-EDTMP对人骨肉瘤细胞株 (HOS - 86 0 3)的辐射效应 ,探讨67Ga作为原发肿瘤和骨转移癌内照射治疗核素的可能性。方法 用成集落实验和透射电镜研究受照细胞的形态变化。结果 发现67Ga-EDTMP对肿瘤细胞有明显的杀伤和抑制增殖作用 ,并随剂量的加大 ,抑制效率增加 ;倒置显微镜下细胞集落数量减少 ,集落偏小 ,细胞稀疏。电镜下胞浆中空泡形成 ,细胞溶解、坏死 ,细胞核固缩 ,出现典型的细胞凋亡改变 ,形成凋亡小体。结论 67Ga可能是一种有前途的骨肉瘤和骨转移癌的放射性治疗核素  相似文献   
59.
胆汁泡蛋白ELISA检测法的建立与初步临床应用   总被引:1,自引:0,他引:1  
目的 建立胆汁泡蛋白快速检测法,筛选有效的胆石症防治手段。方法 获取33.5kd胆汁泡蛋白,通过微量抗原免疫法获得高效价抗体,建立ELISA标准曲线;并应用ELISA法测定正常人、胆石症患者胆汁和血清中泡蛋白含量,同时观察不同溶石防药和利胆冲剂、胆酸钠等对泡蛋白的影响。结果 建立了ELISA标准曲线,其曲线方程为Y=0.035X(r=0.99);正常人胆汁和血清中33.5kd泡蛋白含量都明显较胆固  相似文献   
60.
慢性特发性荨麻疹患者血清组胺释放活性的检测   总被引:7,自引:0,他引:7  
目的 检测慢性特发性荨麻疹患者血中组胺释放活性。方法 自身血清皮肤试验和嗜好性粒细胞组胺释放试验。结果 自身血清皮肤试验和嗜碱性组胺释放试验的阳性率分别为37.5%和43.75%。结论部分慢性特发性荨麻疹患者血中组胺释放活性增高,揭示该类病人具有特殊的肥大细胞和嗜碱性粒细胞激活机制,很可能与自身免疫有关。  相似文献   
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