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21.
反相高效液相色谱法检测小鼠血浆中FG020326方法的建立   总被引:3,自引:3,他引:0  
目的建立测定多药耐药(multidrugresistance,MDR)逆转剂FG020326在KM小鼠血浆中血药浓度的方法。方法将KM小鼠(20·0~25·1)g随机分组,每组6只,♀♂各半,尾静脉注射,给药量为30mg·kg-1,分时取血、处理。采用反相色谱柱,应用外标法测定FG020326在KM小鼠血浆中的血药浓度。结果在所建立的方法学下,FG020326的保留时间为7·9min;标准曲线为Y^=0·0144X-0·0285(r=0·9998),在162·5~41600μg·L-1血浆浓度范围内呈良好的线性关系,最低检测浓度40μg·L-1(S/N=3);在650、2600、20800μg·L-1低、中、高3个浓度下的绝对回收率为68·66%~84·63%,相对回收率为92·58%~110·88%;日内及日间RSD均小于3·2%(n=5)。在室温及冷冻-解冻试验中,FG020326具有良好的稳定性,RSD分别小于1·3%和6·0%。尾静脉单次给药后,FG020326在体内过程符合二室模型,T12α为0·088h,T21β为5·33h,AUC0~∝为14183h·μg·L-1,Vd为0·37L。结论该方法快速、准确、简便,能够满足FG020326药代动力学研究要求。  相似文献   
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14-3-3σ调控p27抑制Rat1-Akt细胞增殖   总被引:1,自引:0,他引:1       下载免费PDF全文
目的: 研究腺病毒介导14-3-3·σ(Ad-14-3-3·σ)对Akt过表达Rat1-Akt细胞增殖的影响,并探讨其作用是否通过调控p27而实现。 方法: 通过5-溴-2′脱氧尿嘧啶(BrdU)实验检测Ad-14-3-3·σ对Rat1-Akt细胞增殖的影响,并通过激酶分析法和免疫荧光实验探讨Ad-14-3-3·σ对p27磷酸化水平及其在细胞内定位的影响。 结果: Ad-14-3-3σ转染的细胞BrdU阳性率(45%)低于PBS处理组(100%)或Ad-β-gal转染的对照组细胞(98%)。14-3-3σ可降低磷酸化p27的水平和减少Akt介导的p27在胞浆中的定位。 结论: 转染14-3-3σ基因能抑制Akt过表达细胞株Rat1-Akt增殖,14-3-3σ通过降低Akt激酶磷酸化p27的活性,阻断Akt介导的p27胞浆错位,从而发挥其抑制Rat1-Akt细胞增殖。  相似文献   
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Nasopharyngeal carcinoma (NPC) is a tumor derived from epithelial cells and Epstein-Barr virus infection has been reported to be a cause of this disease. Chemokine receptor CXCR4 was found to be involved in HIV infection and was highly expressed in human malignant breast tumors and the ligand for CXCR4, CXCL12 (SDF-1), exhibited high expression in organs in which breast cancer metastases are often found. The metastatic pattern of NPC is quite similar to that of malignant breast tumors. In this study, we investigated the expression of CXCR4 in nasopharyngeal carcinoma (NPC) tissues by immunohistostaining. We found different staining patterns, which included localization in the nucleus, membrane, cytoplasm or a combination of them. The staining intensity was also variable among samples. The metastatic rates in patients with high compared to low or absent expression was 38.6% versus 19.8%, respectively (P = 0.004). High expression of CXCR4 was associated with poor overall survival (OS = 67.05% versus 82.08%, P = 0.0225). These results suggest that CXCR4 may be involved in the progression of NPC and that a high level of CXCR4 expression could be used as a prognostic factor.  相似文献   
25.
目的探讨紫杉醇联合草酸铂、卡培他滨三药方案治疗晚期转移性鼻咽癌的疗效及不良反应。方法2002年1月至2005年1月,110例晚期转移性鼻咽癌病人入组:试验组55例患者.第1天应用紫杉醇135mg/m^2、草酸铂130mg/m。静脉滴注,口服卡培他滨1650mg/m^2/d,连服l-14d,每3周为一个周期,连用2-4个周期;对照组55例患者,第1-5天应用DDP 20mg/m^2、5-Fu 0.5g/m^2静脉注射,3周为一个周期,连用2-4个周期;治疗结束2-4周后评价疗效。结果试验组疗效可评价55例,对照组疗效可评价53例。试验组与对照组有效率分别为(CR+PR)50.9%(28例)和32.1%(17例),两者差异有统计学意义(P〈0.05)。试验组和对照组中位生存时间为10.6个月和8.6个月,两者差异有统计学意义(t〈0.05)。安全性方面:试验组Ⅳ反应主要为手足综合征8例(14.5%)、骨髓抑制2例(3.6%)和消化道毒性4例(7.3%);对照组Ⅳ反应主要为消化道毒性8例(15.1%)、骨髓抑制2例(3.8%)。结论紫杉醇联合草酸铂、卡培他滨三药方案对晚期转移性鼻咽癌的疗效较DDP+5-Fu有优势,且不良反应可以耐受。  相似文献   
26.
目的 探讨口服长春瑞滨联合卡培他滨治疗葸环类、紫杉类耐药的转移性乳腺癌的疗效及不良反应。方法 80例确诊葸环类、紫杉类耐药的转移性乳腺癌患者随机分为两组。口服长春瑞滨联合希罗达组(试验组):40例患者口服江苏豪森酒石酸长春瑞滨软胶囊45.50mg/(m^2-d),第1、8、15天服用,口服卡培他滨1650mg/(m^2·d),连服1—14d,每3周为1个周期,连用4个周期。注射长春瑞滨联合希罗达组(对照组):40例患者,长春瑞滨(江苏豪森)25mg/(m^2·d)第1、8天静脉滴注,口服卡培他滨1650mg/(m^2·d),连服1-14d,每3周为1个周期,连用4个周期。治疗结束2周后评价疗效。结果 入组患者80例均可评价疗效,试验组有效率为42.5%,1年生存率为45.0%,中位进展时间4.7月,中位生存时间11.0月;对照组有效率为37.5%,1年生存率为42.5%,中位进展时间4.6月,中位生存时间10.6月;两组比较差异无统计学意义(P〉0.05)。在毒副反应方面,Ⅲ/IV便秘、局部静脉炎、HB下降、WBC下降、ANC下降、总Ⅲ/IV反应率两组比较。差异均有统计学意义(P〈0.05)。结论 口服长春瑞滨联合卡培他滨治疗葸环类、紫杉类耐药的转移性乳腺癌与静脉剂型疗效一致,并且在毒副反应上,口服长春瑞滨明显较静脉剂型轻,并且应用方便。  相似文献   
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BackgroundPrevious studies revealed that patients with early-stage metaplastic breast cancer (MBC) underwent mastectomy more often than breast-conserving therapy (BCT) mainly due to the larger tumor size. This study was performed to compare the survival outcomes following BCT versus mastectomy for patients with early-stage MBC.MethodsSurveillance, Epidemiology, and End Results (SEER) database was used to identify women diagnosed with early-stage MBC (T1-3N0-3M0) between 2001 and 2016, who were treated with either BCT or mastectomy. We assessed overall survival (OS) and breast cancer-specific survival (BCSS) using the Kaplan-Meier method and hazard ratios using Cox proportional hazards models.ResultsA total of 2412 MBC patients were identified, 881 (36.5%) of whom underwent BCT and 1531(63.5%) underwent mastectomy. The median follow-up time was 73 months. Most of patients had older age (≥50 years old), larger tumor size, higher American Joint Committee on Cancer (AJCC) stage and hormone receptor negativity. After adjustment for confounding variables, patients who underwent BCT had significantly improved OS (5-year OS: 84.3% vs 62.5%; 10-year OS: 73.0% vs 52.1%; adjusted HR = 0.76, 95%CI: 0.59–0.97, p = 0.028) and BCSS (5-year BCSS: 89.1% vs 70.8%; 10-year BCSS: 83.9% vs 67.5%; adjusted HR = 0.72, 95%CI: 0.53–0.96, p = 0.026) than those who underwent mastectomy, and this improvement remained significant for all T and N stages of MBC except for N2-3 stage.ConclusionBCT conferred improved OS and BCSS compared with mastectomy for patients with early-stage MBC, and the improvement persisted in almost all of the subgroups of different T and N stages.  相似文献   
29.
BackgroundFew studies evaluate the relationships between surgical approach, histologic margin, and overall survival in gastrointestinal stromal tumor. We test the hypothesis that margin positive resection is associated with compromised overall survival.MethodsWe queried the National Cancer Data Base to identify patients undergoing resections for gastrointestinal stromal tumors ≤3 cm in size between 2010 and 2015. Multivariable logistic regression was used to identify factors associated with positive microscopic margins on final pathology. Cox proportional hazard methods were used to evaluate factors associated with overall survival.Results2064 patients met inclusion criteria; 135 (6.5%) had a microscopically positive surgical margin. On multivariable regression, minimally invasive approach was not associated with risk of a positive margin (OR 1.06 95% CI [0.71, 1.59]). On Cox analysis, positive margin status was not associated with OS (R1: 1.03, CI [0.46–2.31], reference R0).ConclusionsPositive microscopic surgical margins are not associated with compromised overall survival in patients undergoing resection of small gastrointestinal stromal tumors. Minimally invasive surgical approaches do not compromise oncologic outcomes in these cases.  相似文献   
30.
PurposeWe determined whether a clinicopathological nomogram is able to predict the risk of pelvic lymph node metastasis (LNM) in penile cancer patients after inguinal lymph node dissection (ILND).MethodsNinety-eight patients with bilateral ILND who underwent pelvic lymphadenectomy at 10 centers were retrospectively analyzed. The most predictive features in the nomogram were selected by the stepwise logistic regression method and then tested and verified by multivariate logistic regression analyses. The nomogram was assessed using concordance indices and calibration curves.ResultsOf the 181 pelvic basins, pelvic LNM was observed in 52 packages (43 patients). Bilateral pelvic LNM was present in 9 patients (9/43, 20.9%). There was no crossover metastatic spread from one inguinal side to the other pelvic side. Age, previous resection, the biopsy procedure for inguinal lymph nodes, vascular invasion, and ipsilateral inguinal lymph node status were all independent risk factors for pelvic LNM (all P < 0.05) in the multivariate logistic regression analysis. The nomogram exhibited a good probability for survival agreement, with a concordance index of 0.868 (95% CI: 0.813–0.922).ConclusionsA novel nomogram suggests that the risk of pelvic LNM can be effectively predicted in penile carcinoma patients and may provide a useful guide for clinicians. Further external validation is needed.  相似文献   
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