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1.
赛赓啶对 KBV200细胞多药抗性的逆转作用   总被引:3,自引:0,他引:3  
研究赛赓啶对KBV200细胞多药抗性的逆转作用及逆转机制。在KBV200细胞,采用MTT法,测出赛赓啶对长春新碱、阿霉素和鬼臼乙叉甙耐药的逆转系数分别为5.5,2.0和1.9,而对5-氟尿嘧啶、美法仑的细胞毒性作用无明显影响,表明赛赓啶为多药抗性逆转剂。荧光分光光度法测定表明,赛赓啶可使KBV200细胞内阿霉素蓄积量增加。流式细胞荧光测定显示赛赓啶可增加罗丹明123的蓄积并减慢其外排。免疫细胞化学及狭缝杂交表明赛赓啶不影响KBV200细胞的P-糖蛋白染色深度和 mdr1 RNA 表达水平。以上结果提示赛赓啶的多药抗性逆转机制是抑制P-糖蛋白泵的功能。  相似文献   
2.
BACKGROUND: Hepatocellular carcinoma (HCC) is one of the most prevalent fatal cancers in the world. Despite advances in early diagnosis and improvements in surgical techniques, the survival of patients with HCC even after resection is poor because of the high incidence of recurrences. Therefore, the identification of prognostic factors may be helpful in the development of new treatment protocols. AIMS: To investigate HER-2/neu status in HCC by immunohistochemistry (IHC) and fluorescence in situ hybridisation (FISH), and to explore the possibility of using trastuzumab in the treatment of HCC. METH ODS: Eight hundred and sixty eight surgical samples from patients with primary HCC were examined for their HER-2/neu status. IHC for HER-2/neu was performed with the HercepTest kit; FISH analysis was performed with the PathVysion HER-2 DNA probe kit. The correlations between HER-2/neu overexpression and clinicopathological characteristics were analysed statistically. RESULTS: HER-2/neu overexpression was detected in 21 (2.42%) of the 868 primary HCCs. Only one specimen showed HER-2/neu gene amplification by FISH. No significant associations were found between HER-2/neu overexpression and the clinicopathological parameters. CONCLUSIONS: There is a low frequency of HER-2/neu overexpression/amplification in HCC. There appears to be no role for HER-2/neu as a prognostic marker and no benefit of anti-HER-2/neu trastuzumab treatment in patients with HCC.  相似文献   
3.
PURPOSETo describe a high-resolution MR imaging technique that depicts the complex anatomy of the region of the parotid gland, focusing on the intraparotid components of the facial nerve and parotid duct.METHODSHigh-resolution T1-weighted images of the parotid gland were acquired with a prototype three-dimensional Fourier transform gradient-echo sequence that permits a very short echo time (4.2 milliseconds) by using a modified phase-encoded time-reduced acquisition scheme. The sequences were obtained at 1.5 T with a head and neck coil. Postprocessed multiplanar, curved and volumetric images were obtained. The most clinically useful images were acquired at parameters of 40/4.2 (TR/TEeff) a flip of 30 degrees, a field of view of 18 to 20 cm, a matrix of 512 x 288 or 512 x 256, an axial plane, 60 images, no gaps, and a section thickness of 1.5 mm. Eighteen healthy subjects were examined. The position of the facial nerve within the parotid gland was determined by identifying the facial nerve in the stylomastoid foramen and then following it on sequential sections through the parotid gland. Curved reformations were used to confirm the visibility of the nerve. A similar technique was used for the parotid duct.RESULTSThe image contrast obtained was similar to that of standard spin-echo T1-weighted images. The parotid gland showed intermediate signal intensity while the fat spaces showed high signal intensity. The vessels had variable signal intensity depending on saturation. The cerebrospinal fluid, nerves, muscles, and ducts had lower signal intensity. In all 18 subjects, the facial nerve from the brain stem to the parotid gland, and the parotid duct from the mouth to the hilus of the gland were seen bilaterally. The proximal intraparotid facial nerve to the level of the retromandibular vein was seen in 72% of the subjects and the main intraparotid ducts were seen in 66% of the subjects.CONCLUSIONHigh-resolution MR imaging offers simultaneous display of most of the important structures in the region of the parotid gland, including the intraparotid duct and facial nerve.  相似文献   
4.
目的探讨微机对青霉素皮试结果作辅助判断的准确性。方法我们根据青霉素皮试常规观察指标设计了青霉素皮试观察记录单,分三个时段观察青霉素皮试的结果。计算机程序判断青霉素皮试的结果是对观察记录经过综合分析得出的。结果应用计算机对376例青霉素皮试的结果进行辅助判定,其结果表明计算机程序对青霉素皮试结果的判断正确性不低于人工判定,经χ2检验P>0.05,说明两者判断结果无显著性。  相似文献   
5.
Introduction  Wide awake open carpal tunnel decompression is a procedure performed under local anesthesia. This study aimed to present the effect of various local anesthetics in peri and postoperative analgesia in patients undergoing this procedure. Materials and Methods  A total of 140 patients, with 150 hands involved, underwent carpal tunnel release under local anesthesia. Patients were divided in five groups according to local anesthetic administered: lidocaine 2%, ropivacaine 0.75%, ropivacaine 0.375%, chirocaine 0.5%, and chirocaine 0.25%. Total 400 mg of gabapentin were administered to a subgroup of 10 cases from each group (50 cases totally), 12 hours before surgery. Patients were evaluated immediately, 2 weeks and 2 months after surgery according to VAS pain score, grip strength, and two-point discrimination. Results  In all patients, pain and paresthesia improved significantly postoperatively, while the use of gabapentin did not affect outcomes. Grip strength recovered and exceeded the preoperative value 2 months after surgery, without any difference between the groups. No case of infection, hematoma, or revision surgery was reported. Conclusion  Recovery after open carpal tunnel release appears to be irrelevant of the type of local anesthetic used during the procedure. Solutions of low local anesthetic concentration (lidocaine 2%, ropivacaine 0.375%, and chirocaine 0.25%) provide adequate intraoperative analgesia without affecting the postoperative course.  相似文献   
6.
Distal tibial epiphyseal fractures in adolescents.   总被引:1,自引:0,他引:1  
The characteristic pattern of fusion of distal tibial epiphysis explains the special configuration of the fragments in the triplane fracture and the "juvenile" fracture of Tillaux in adolescents. The application of external rotation force produces Tillaux and triplane fractures of the lateral portion of the distal tibial epiphysis in patients with a mean age of 13.5 years. Eight patients, 13 to 15 years of age, with distal tibial epiphyseal fractures were treated in the last 12 years. Three of the fractures were classified as "juvenile" Tillaux fractures and five were triplane fractures. Open reduction and fixation of the tibia was accomplished by using either malleolar screws or K-wires. Follow-up time ranged from 1.5 to 11 years. All patients were evaluated subjectively and objectively after surgery. Objective evaluation included clinical assessment and radiographic evaluation. All patients regained full range of motion and no one complained of pain or joint stiffness. Radiographs confirmed that all fractures have healed without articular incongruity.  相似文献   
7.
In order to enhance the immune efficacy of DNA vaccination, experiments were conducted to investigate the regulating effects of Bacillus Calmette-Guerin (BCG)-DNA as an adjuvant on immune responses of mice against foot-and-mouth disease (FMD), Aujeszky's disease (AID) and classical swine fever (CSF). BCG-DNA was purified from BCG by ion-exchange chromatography. Three DNA vaccines (pVSG, pVgD and pVE2) against the respective infection were constructed, and BCGDNA was coimmunized to mice by muscle injection. The results showed that titres of specific immunoglobulin (Ig)G to the vaccines mounted remarkably in the sera of the adjuvant covaccinated mice (P〈0.01). Antibody isotype IgG2a and IgG1 also increased, respectively, in mice coimmunized with BCG-DNA compared with those of the control groups (P〈0.01). Cellular immune cytokine interferon-gamma and cytotoxic T lymphocytes were detected in coimmunized BCG-DNA groups (P〈0. 05). Whereas interleukin-4, humoral immune cytokine, was not significant (P〉 0. 05). These results suggest that codelivery of BCG-DNA with DNA vaccines against FMD, AjD and CSF can enhance the induction of antigen-specific, especially, cell-mediated immunity.  相似文献   
8.
目的:分析首乌丹参方预处理对大鼠心肌缺血再灌注损伤的保护机制是否通过促进蛋白激酶CmRNA水平表达发挥作用。方法:实验于2003-07/2004-05在天津中医药大学中医药研究中心省部共建教育部方剂学重点实验室完成。SPF级雄性Wistar大鼠,体质量(336±20)g。随机数字表法分为7组:假手术组(取血清作正常对照)、模型组、首乌丹参方高剂量组、(9g/kg)、首乌丹参方中剂量组(4.5g/kg)、首乌丹参方低剂量组(2.25g/kg)、复方丹参滴丸阳性对照组(4.5g/kg)、消心痛对照组(1.67mg/kg),每组12只。首乌丹参方浸膏,由天士力药业集团提供,100g生药出膏15.26g(每克浸膏的生药量为6.55g),批号:20020318,给药剂量分别为9,4.5,2.25g/kg,实验前称取一定量的浸膏,用0.5%羧甲基纤维素钠分别配成0.9,0.45,0.225g/mL浓度的混悬液,每克生药加天然冰片5.19mg。阳性对照药复方丹参滴丸浸膏,黑褐色,由天士力药业集团提供,100g生药出膏21.47g(每克浸膏的生药量为4.66g,批号:20020423)。给药剂量以生药计算为4.5g/kg,每克生药加合成冰片6.15mg;阳性对照药消心痛(硝酸异山犁酯)片,每片含消心痛5mg,天津太平洋制药有限公司生产(批号:20040302),药液浓度0.167mg/mL,配制方法同上。采用结扎大鼠冠状动脉前降支30min/开放120min建立心肌缺血再灌注损伤模型。假手术组只穿线不结扎,30min时将所穿线迅速拎起后再放下,快速关胸。造模后假手术组、模型组给0.5%羧甲基纤维素钠液,余组将药物用0.5%羧甲基纤维素钠配制成混悬液,给药体积皆为1mL/100g。通过RT-PCR分子生物学方法观察蛋白激酶CmRNA表达情况以及首乌丹参方预处理对其的影响。结果:84只大鼠均进入结果分析。与假手术组相比,模型组和首乌丹参方各组蛋白激酶CmRNA表达均有所下降;与模型组相比,首乌丹参方中剂量组、复方丹参滴丸阳性对照组和消心痛对照组表达上调,差异均有显著性意义,首乌丹参方高剂量组及低剂量组也能促进蛋白激酶CmRNA的表达,但差异没有显著性意义。结论:首乌丹参方预处理可促进缺血再灌注损伤大鼠心肌蛋白激酶C表达。首乌丹参方可能通过激动蛋白激酶C对缺血再灌注损伤的心肌起保护效应。  相似文献   
9.
目的:采用不同方法对白血病HL60细胞株进行冻存和复苏,观察生物学特性改变,筛选最佳冻存复苏方案。方法:实验于2006-04/06在吉林医药学院临床检验实验室(国家三级标准)进行。①HL60细胞株由中国科学院上海生物细胞研究所提供。将欲冷冻保存的HL60细胞调整到良好的生长状态(对数生长期),随机数字表法分成4组,离心收集后在含体积分数为0.1小牛血清的RPMI-1640培养基中分别加入二甲基亚砜,使其终浓度依次为50,100,150,200g/L。冻存15d后,每组取1支冻存管复苏并接种于细胞培养板,培养12h后用锥虫蓝拒染法计算细胞复苏率。②选择冻存条件和冻存细胞密度相同的两支冻存管,按不同方法进行HL60细胞复苏。37℃水浴传统复苏法:立即将冻存管置于37℃水浴中,待融化后800r/min离心5min,吸去上清液,加入含体积分数为0.1小牛血清的RPMI-1640培养基,混匀后接种于细胞培养板,1mL/孔,9孔/组,置于体积分数为0.05的CO2培养箱37℃继续培养。40℃溶解后再37℃恒温改良复苏法:将冻存细胞于40℃水浴中迅速溶解,转入37℃水浴箱,融化后离心、加培养基等操作同传统复苏法。复苏细胞培养12h后采用锥虫蓝染色计算细胞存活率。③用无血清RPMI-1640培养基制备HL60细胞悬液,按3×107L-1密度接种于细胞培养板中,1mL/孔,然后分别加入体积分数为0.05,0.1,0.12,0.15,0.2的灭活小牛血清,每种血清浓度设置8个试验孔,并分别于培养12,24,36,48,60,72,84,96h后计数每孔细胞数量,并绘制细胞生长曲线。结果:①不同浓度二甲基亚砜冻存后HL60细胞复苏率的比较:二甲基亚砜200g/L组的细胞复苏率明显低于二甲基亚砜50,100,150g/L组[(64.6±2.8)%,(87.0±1.4)%,(86.4±2.1)%,(85.7±2.8)%;t=25.44,P<0.01],二甲基亚砜50,100,150g/L组间差异无显著性意义(t=0.82~1.44,P>0.05)。②不同复苏方法HL60细胞存活率的比较:与37℃水浴传统复苏法比较,40℃溶解后再37℃恒温改良复苏法的细胞存活率显著升高[(69.5±1.5)%,(87.4±1.8)%,t=23.24,P<0.01]。③RPMI-1640培养基不同血清含量对HL60细胞生长情况的影响:在体积分数为0.05的血清含量培养基中,HL60细胞基本不生长,且有逐渐死亡的趋势;在体积分数为0.1的血清含量培养基中,HL60细胞生长趋势明显,但生长速度相对较慢;在体积分数为0.12,0.15,0.2的血清含量培养基中,HL60细胞生长迅速,3种血清浓度间细胞生长趋势无明显差异。结论:以50g/L二甲基亚砜作为HL60细胞冻存保护剂、联合40℃溶解后再37℃恒温改良复苏法可使细胞保持最佳生物学特性,体积分数为0.12的血清含量为HL60细胞常规培养的最适浓度。  相似文献   
10.
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