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81.
Adenoid cystic carcinoma of the salivary glands is characterized by a poor response to chemotherapy. Most cases of adenoid cystic carcinoma express the c-kit protein. Imatinib mesylate (Gleevec) inhibits several protein-tyrosine kinases, including c-kit. We therefore hypothesized that Imatinib may be an effective drug in patients with locally advanced or metastatic adenoid cystic carcinoma and conducted a phase 2 trial in order to study this. Patients with locally advanced or metastatic adenoid cystic carcinoma and c-kit positive tumours were eligible. Fourteen patients were screened and 10 patients (71%) with c-kit positive tumours entered the study. Treatment was begun at a dose of Imatinib of 400mg/day. Dose escalation was allowed in the absence of toxicity. The dose was increased to 600mg/d in three patients and 800mg/d in one patient. Three patients required dose reduction to 300mg/d, due to grade 3 toxicity. No grade 4 toxicity was seen. No objective responses were seen. Two patients (20%) exhibited stable disease for 11 and 14 months, respectively. All other patients stopped treatment after 2-14 (median 6) months due to progressive disease. Imatinib has no major effect on advanced adenoid cystic carcinoma of the head and neck.  相似文献   
82.
Microsurgical free flaps are common in head and neck reconstruction, and their techniques and outcomes have continuously improved during the past decades. However, there are variations in practice among surgeons between the use of closed-suction drainage systems and Penrose drains. The proponents of Penrose drains propose that the negative pressure generated by the closed-suction drainage system may harm the microvascular anastomosis. We know of no previous studies that have compared the two drains for microvascular free flap reconstruction, so our aim was to compare them in a single-centre, retrospective review of all patients who had microvascular free flap reconstruction of the head and neck region in our department between 1 November 2010 and 1 September 2017. During this period 84 patients had 87 free flap reconstructions in the head and neck, 43 of which had Penrose, and 44 closed-suction, drainage. We compared the number of complications between the groups including haematomas, seromas, wound infections, anastomostic thrombosis, anastomotic revision, and need for re-exploration. There were no significant differences between the groups, despite a trend toward fewer negative explorations in the closed-suction group. There were no differences in complications between suction and passive drainage systems after microvascular free flaps, which suggests that closed suction drainage could be safely used after free flap reconstruction in the head and neck.  相似文献   
83.
为进一步了解维拉帕米对抗药性逆转作用的待征,在人MDR1基因转染的Swiss-3T3多药抗药性细胞,观察了维拉帕米逆转幅度与阿霉素抗性水平的关系。各个转染细胞与母细胞相比,阿霉素毒性明显降低。非毒性浓度(3Umol·L-1)的维拉帕米对阿霉素毒性的增强作用,在转染细胞均高于母细胞,但逆转幅度与抗性水平成反比。Southern杂交显示,转染细胞基因组中有MDR1cDNA整合。转染细胞的阿霉素蓄积障碍可被维拉帕米纠正。讨论了药物主动转运的饱和现象在维拉帕米增强效应中的作用,以及P-糖蛋白与药物相互作用的方式。  相似文献   
84.
为观察速激肽NK-1受体拮抗剂SR-140333对抗原攻击引起的致敏大鼠气道高反应性的影响,测定了致敏大鼠在抗原攻击前后的基础呼吸频率,对MCh的反应性及支气管-肺泡灌洗液中的白细胞数量。实验结果显示,致敏大鼠吸入OA后6h基础呼吸频率增加,并显著增加乙酰甲胆碱(MCh)的反应性、MCh的-logPC30值和支气管-肺泡灌洗液中的白细胞数量。ip速激肽NK-1受体拮抗剂SR-140333(0.1mg·kg-1)或地塞米松(0.5mg·kg-1),可明显抑制上述反应,小剂量SR-140333(0.01mg·kg-1)仅有部分抑制作用。结果提示抗原攻击可引起致敏大鼠气道高反应性和气道炎症,速激肽NK-1受体拮抗剂可抑制这些反应。  相似文献   
85.
Exosomes are membrane‐bound vesicles of endosomal origin, present in a wide range of biological fluids, including blood and urine. They range between 30 and 100 nm in diameter, and consist of a limiting lipid bilayer, transmembrane proteins and a hydrophilic core containing proteins, mRNAs and microRNAs (miRNA). Exosomes can act as extracellular vehicles by which cells communicate, through the delivery of their functional cargo to recipient cells, with many important biological, physiological and pathological implications. The exosome release pathway contributes towards protein secretion, antigen presentation, pathogen transfer and cancer progression. Exosomes and exosome‐mediated signalling have been implicated in disease processes such as atherosclerosis, calcification and kidney diseases. Circulating levels of exosomes and extracellular vesicles can be influenced by the progression of renal disease. Advances in methods for purification and analysis of exosomes are leading to potential diagnostic and therapeutic avenues for kidney diseases. This review will focus on biophysical properties and biogenesis of exosomes, their pathophysiological roles and their potential as biomarkers and therapeutics in kidney diseases.  相似文献   
86.
Huang  MT; Lou  YR; Xie  JG; Ma  W; Lu  YP; Yen  P; Zhu  BT; Newmark  H; Ho  CT 《Carcinogenesis》1998,19(9):1697-1700
Female Sencar mice (6 weeks old) were administered 1 mg of 7,12- dimethylbenz[a]anthracene (DMBA) by oral gavage once a week for 5 weeks. At 20 weeks after the first dose of DMBA, 68% of mice developed mammary tumors (the average 1.08 tumors per mouse) and 45% had lymphomas/leukemias. Feeding 1% dibenzoylmethane (DBM) in AIN 76A diet, starting at 2 weeks before the first dose of DMBA and continuing until the end of the experiment, inhibited both the multiplicity and incidence of DMBA-induced mammary tumor by 97%. The incidence of lymphomas/leukemias was completely inhibited by 1% DBM diet. In contrast, feeding 2% curcumin diet had little or no effect on the incidence of mammary tumors, and the incidence of lymphomas/leukemias was reduced by 53%.   相似文献   
87.
血清反复冻融对HBsAg和抗HBs抗体检测的影响   总被引:1,自引:0,他引:1  
0 引言  EL ISA技术已在乙肝标志物的检测中已普遍应用 ,一般认为收集的血清应及时检测 .而在基层单位或在流行病学调查研究中 ,由于血标本收集不集中 ,或者有些标本常需检测多个指标而持续时间较长 ,因此 ,血清必须低温贮存一定时间或反复冻融后检测 ,而血清冻融对 EL ISA检测结果是否有影响尚不清楚 .为此 ,我们对 183份血清标本冻融前、冻融 3次、冻融 6次后的 HBs Ag和抗 - HBs进行了检测和分析比较 .1 材料和方法1.1 材料  1999- 0 5收集西京医院门诊乙肝 5项检测血清183份 ,年龄、性别、诊断不限 .1.2 方法 于初次检测 …  相似文献   
88.
目的:观察承载丸含药血清对甲基强的松龙预处理的MC3T3-E1成骨细胞L-钙通道电流的影响。方法:实验于2006-04/06在中国中医科学院望京医院药理实验室及吉林大学基础医学院生理教研室完成。①实验材料:MC3T3-E1(购于北京协和细胞中心);8个月龄SD大鼠10只,雌雄各半;中药制剂承载丸(由鹿角霜、肉苁蓉、续断、黄芪、当归、炙水蛭、杜仲、蛋衣、皂角刺、香附、乌药等21味中药组成);甲基强的松龙(批号H20040338,Pharmacia NV/SA生产)。②实验干预:成骨细胞(MC3T3-E1)传代培养。承载丸药粉60g,加水至200mL搅匀,取大鼠6只(雌雄各半),每只灌服2.5mL/d,灌服4d后动脉取血,制备含药血清。另取大鼠4只,同法灌服生理盐水,制成不含药血清。甲基强的松龙的浓度为1×10-5mol/L。③实验分组:将培养后的成骨细胞株分为4组:正常组(加入正常大鼠不含药血清)、模型组(加入正常大鼠不含药血清及甲基强的松龙)、承载丸低剂量组(加入甲基强的松龙及0.5mL承载丸含药血清)和承载丸高剂量组(加入甲基强的松龙及0.1mL承载丸含药血清)。④实验评估:24h后,用全细胞膜片钳技术记录每组10个细胞的L-钙通道电流,并测定其峰值电流。结果:①各组电流峰值测定结果:模型组峰值电流比正常组下降19.5%[(0.1839±0.0179),(0.2284±0.0209)nA,P<0.01];承载丸低剂量组和高剂量组比模型组分别升高37.4%和45.2%[(0.2526±0.0093),(0.2671±0.0120),(0.1839±0.0179)nA,P<0.01];承载丸高低剂量组相比差异有显著性意义(P<0.05)。②MG3T3E1细胞钙电流的特性分析:正常组,钙通道大约在-20mV时开放,最大峰值电流在 20~ 30mV,反转电位在 60~ 70mV。当在浴液中加入Co2 ,可阻断此电流的大部分电流成份,其峰值电流为(0.1050±0.0097)nA,而钙离子激活剂Bayk8644增加了此电流(0.3335±0.0323)nA。结论:①甲基强的松龙抑制成骨细胞L-钙通道电流。②承载丸含药血清可升高甲基强的松龙预处理的成骨细胞L-钙通道电流。  相似文献   
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