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991.
以乙烯基萘(VN)为聚合单体,采用乳液聚合法制备聚乙烯基萘(PVN)纳米微球。通过对其羧基化与β2微球蛋白(β2-M)抗体偶联,制成免疫检测试剂。分别用聚苯乙烯(PS)和 PVN 检测试剂测定β2-M 含量,数据经统计学处理和分析,对自制的 PVN 纳米微球胶乳增强免疫比浊( LE-TIA)检测试剂的性能进行评价。自制的羧基化 PVN 纳米微球免疫试剂成功对标准样本进行了检测并在一定范围内有较好的线性,比 PS 检测试剂更加灵敏。利用该研究采用的方法和条件可以成功制备粒径大小可控、单分散的羧基化PVN 纳米微球,是比 PS 更优的 LETIA 新载体,具有很好的临床应用前景。  相似文献   
992.
目的 构建人β-连环蛋白(β-catenin)与增强型绿色荧光蛋白(EGFP)融合表达的慢病毒载体,感染人毛囊干细胞并予以鉴定.方法 提取人血管内皮细胞总RNA,RT-PCR扩增获得β-catenin基因全部序列,采用TA克隆技术获取基因亚克隆pUCm-T-β-catenin,AgeⅠ酶切连接pGC-FU载体构建β-catenin融合EGFP共表达慢病毒载体质粒pGC-FU-β-catenin-EGFP.质粒转化感受态细菌,筛选阳性克隆,经RT-PCR及测序鉴定正确后转染FT293细胞,Western blotting分析鉴定.质粒再转染FT293细胞进行慢病毒质粒包装,荧光显微镜观察,Real-time PCR测定病毒滴度.包装后慢病毒质粒感染体外分离和培养经免疫荧光染色鉴定的人毛囊干细胞,RT-PCR鉴定,荧光显微镜观察感染效率.结果 RT-PCR及测序鉴定证实目的 基因正确克隆至慢病毒载体中.在转染pGC-FU-β-catenin-EGFP的FT293细胞,Western blotting证实细胞表达β-catenin;质粒包装后荧光显微镜观察FT293细胞见大量绿色荧光时测得病毒滴度为2.0×108 TU/mL.在感染慢病毒质粒的人毛囊干细胞,当感染复数为10时,感染后48 h的感染效率可达80%以上,感染后3周的感染效率仍维持在80% ~90%.结论 成功构建β-catenin-EGFP融合表达慢病毒载体,可高效感染人毛囊干细胞且表达稳定、持久.  相似文献   
993.
目的观察特发性颅内压增高(IIH)病人治疗前后静脉窦大小变化,探讨静脉窦狭窄与IIH的关系。方法将2010年5月至2013年12月就诊并初步诊断为IIH的病人15例纳入研究。所有病例于治疗前后均行腰椎穿刺术、MRI常规和增强扫描及三维对比增强静脉成像(3D CE-MRV)检查。结果 15例IIH脑脊液压力均〉250 mm H2O,平均值为407.69 mm H2O。治疗前颅内静脉窦不同程度狭窄,Gale静脉、上矢状窦、左侧横窦、右侧横窦狭窄处横截面积分别为(13.7±8.1)、(21.3±11.4)、(11.8±8.1)和(10.0±5.8)mm2。治疗后静脉窦不同程度扩张,Gale静脉、上矢状窦、左侧横窦、右侧横窦狭窄处横截面积分别为(36.9±16.1)、(32.3±14.5)、(25.0±18.3)和(47.0±23.4)mm2。2例IIH横窦仍持续存在狭窄。结论静脉窦狭窄作为一种表现可以继发于IIH,作为一种诱因可导致IIH的发病,作为一种解剖变异又可以存在于正常人群。  相似文献   
994.
This paper aims to study whether cyclosporine‐A (CSA) levels have an impact on the clinical outcome of patients with T‐cell replete haploidentical allogeneic hematopoietic stem cell transplantation (allo‐HSCT). We analyzed 140 consecutive patients who had been given T‐cell replete haploidentical allo‐HSCT in our institute to assess the effect of CSA concentration in the early stages of allo‐HSCT on clinical outcomes, such as hematopoietic recovery, acute graft vs host disease (aGVHD), infection, disease‐free survival (DFS), and overall survival (OS). The median concentrations of CSA in the blood in the 1st, 2nd, 3rd, and 4th week after allo‐HSCT were 218, 235, 263, and 270 ng/mL, respectively. Additionally, 46%, 40%, 27%, and 18% of the patients had CSA blood levels below 200 ng/mL during those weeks. In total, 39 patients developed aGVHD (grade II‐IV), for a cumulative incidence of 27.8%, at a median of 32 days. Patients having a low CSA concentration (below 200 ng/mL) in the 3rd week had a higher cumulative incidence of grade II‐IV aGVHD (= .02). In addition, multivariate logistic regression analysis showed that low CSA concentration (below 200 ng/mL) in the 3rd week was an independent risk factor of grade II‐IV aGVHD (= .02; odds ratio = 2.66; 95% CI, 1.15‐6.17). However, CSA levels during the first 4 weeks did not have a significant impact on the patients’ hematopoietic recovery, infection, DFS, and OS. Our data indicated that adequate management of CSA levels during the peri‐engraftment period might improve clinical outcomes for those with T‐cell replete haploidentical allo‐HSCT.  相似文献   
995.
The concept of dose-dense chemotherapy has emerged and is based on the hypothesis that maximal chemotherapy effectiveness can be achieved by scheduling the interval of chemotherapy to correspond to the period of most rapid tumor growth, as predicted by preclinical models. The granulocyte-colony stimulating factor support has permitted the safe delivery of chemotherapy at shorter ("dose-dense") inter-treatment intervals. Several randomized trials have been conducted to test the feasibility and effectiveness of anthracycline and/or taxanes-based dose-dense strategies. They have been associated with a modest impact on disease recurrence and overall survival of patients with early-stage breast cancer. Subset analyses have suggested increased benefits for specific tumor subtypes such as hormone receptor-negative, highly proliferative or HER2 overexpressing tumors. This review article aims to outline the theoretical framework for dose-dense chemotherapy and summarizes the results of several recent clinical trials addressing this concept within neoadjuvant and adjuvant breast cancer treatment and discuss their implications for clinical practice. Further studies are needed to define the optimal regimen and the patient population that will receive the greatest benefit from dose-dense strategy.  相似文献   
996.
Limited organ supply has led to greater use of liver allografts with higher donor risk indices (DRI) and/or donated after cardiac death (DCD). DCD status is associated with acute kidney injury after liver transplantation; however, less is known about the association between donor quality and end‐stage renal disease (ESRD). Using SRTR data, we assembled a cohort of liver transplant recipients from 2/2002 to 12/2010. We fit multivariable Cox regression models for ESRD. Model 1 included total DRI; model 2 included components of DRI, including DCD, as separate variables. Forty thousand four hundred and sixty‐three liver transplant recipients were included. Median DRI was 1.40 (IQR 1.14, 1.72); 1822 (5%) received DCD livers. During median follow‐up of 3.93 years, ESRD occurred in 2008 (5%) and death in 11 075 (27%) subjects. There was a stepwise increase in ESRD risk with higher DRI (DRI ≥1.14 and <1.40: HR 1.17, P = 0.06; DRI ≥1.40 and <1.72: HR 1.29, P = 0.003; DRI ≥1.72: HR 1.39, P < 0.001, compared with DRI <1.14). Adjusting for DRI components separately, DCD status was most strongly associated with ESRD (HR 1.40, P = 0.008). Higher DRI is associated with ESRD after liver transplantation, driven in part by DCD status. Donor quality is an important predictor of long‐term renal outcomes in liver transplant recipients.  相似文献   
997.
BACKGROUND: In this study, we investigated the expression of HER-2/neu and AR in clinically organ-confined prostate cancer to determine whether alterations in these signaling pathways contribute to the development of metastatic disease. METHODS: HER-2/neu and AR immunoreactivity were evaluated in archived prostatic tissues obtained from 53 men with clinically organ-confined disease who underwent radical prostatectomy. Associations between AR and HER-2/neu immunostaining and disease outcome were determined. RESULTS: Seventy percent (37/53) of tumors exhibited high levels of HER-2/neu immunostaining and 68% (36/53) of tumors had elevated AR levels. Patients with high levels of both HER-2/neu and AR had the highest rate of PSA failure (56%, 15/27) compared with no PSA failures amongst seven patients with low levels of both HER-2/neu and AR (log rank statistic 7.69, P = 0.021). Concurrent high levels of HER-2/neu and AR expression were significantly associated with high pathological stage (P = 0.027) and development of metastatic disease (P = 0.022). CONCLUSIONS: These findings support the notion that both the HER-2/neu and AR signaling pathways may contribute to development of metastatic disease. The subset of prostate tumors with increased HER-2/neu and AR levels may benefit from treatment strategies that target both signaling pathways.  相似文献   
998.
BACKGROUND: The ARCaP cell line was established from the ascites fluid of a patient with metastatic prostate cancer. This study characterized the host microenvironmental role in cancer progression, epithelial to mesenchymal transition (EMT), and bone and adrenal metastasis in parental ARCaP and its derived cell subclones. METHODS: Cytogenetic profiles, growth, migration, invasion, cellular interaction, drug sensitivities, and gene expression of ARCaP cell subclones were compared. In vivo gene expression, behavior, and metastasis of ARCaP subclones were analyzed by serial intracardiac injections into SCID mice. RESULTS: ARCaP(E) cells, with cobblestone morphology, underwent EMT through cellular interaction with host bone and adrenal gland. Lineage-derived ARCaP(M) cells, with spindle-shape fibroblastic morphology, exhibited decreased cell adhesion and increased metastasis to bone and adrenal gland. Cytogenetic analyses of parental and ARCaP subclones confirmed their clonality. CONCLUSIONS: ARCaP uniquely models the molecular basis of prostate cancer bone and adrenal metastases and epithelial to mesenchymal transition.  相似文献   
999.
Q. Bin  J. Li  C. Liao  Y. Cao  F. Gao 《Colorectal disease》2011,13(8):837-845
Aim The aim of this study was to evaluate systematically the efficacy and safety of oral uracil‐tegafur (UFT) plus leucovorin (LV) compared with infusional fluorouracil (5‐FU) plus LV for advanced colorectal cancer. Method Eligible studies were identified from Medline, Embase and the Cochrane Library. The end‐points included overall survival and overall tumour response rate, and toxicity including leucopenia, febrile neutropenia, stomatitis/mucositis and diarrhoea. Results Five randomized controlled trials were identified. Pooled data demonstrated no difference in overall survival between the oral UFT plus LV regimen and the 5‐FU bolus plus LV regimen [hazard ratio 1.013; 95% confidence interval (CI) 0.911–1.127].The fixed‐effect pooled estimate for overall tumour response rate showed no significant difference between the two regimens (relative risk 0.893; 0.672–1.187). Grade 3–4 leucopenia [odds ratio (OR) 0.126; 955 CI 0.048–0.326], grade 1–4 leucopenia (OR 0.089; 95% CI 0.067–0.119) and grade1–4 febrile neutropenia (OR 0.020; 95% CI 0.004–0.102) were significantly less prominent in the oral UFT regimens. For nonhaematological toxicities, grade 3–4 stomatitis/mucositis (OR 0.075; 95% CI 0.039–0.146), grade 3–4 infection (OR 0.484; 95% CI 0.310–0.758), grade 1–4 infection (OR 0.672; 95% CI 0.547–0.826, P < 0.001), grade 1–4 diarrhoea (OR 0.743; 95% CI 0.626–0.881) were also less likely to happen in patients in the oral UFT plus LV regimen, while there was no significant difference between the two treatment regimens with respect to grade 1–4 stomatitis/mucositis (OR 0.278; 95% CI 0.053–1.456) and grade 3–4 (OR 1.174; 95% CI 0.983–1.403) diarrhoea. Conclusion Oral UFT or 5‐FU bolus combined with LV results in similar overall survival and tumour response rates for advanced colorectal cancer. The former treatment regimen is greatly superior in terms of toxicity, especially haematological toxicity.  相似文献   
1000.
脂肪肝灰阶超声造影定量研究   总被引:3,自引:0,他引:3  
目的 应用灰阶超声造影定量研究脂肪肝的超声造影增强情况.方法 脂肪肝及正常肝各12例,应用低机械指数灰阶超声造影和时间-强度曲线定量分析脂肪肝与正常肝的造影增强效应.结果 脂肪肝的前、中场与相同部位的正常肝比较超声造影峰值强度降低.结论 脂肪肝超声造影增强效应低于正常肝,可能影响中后场病灶的观察.如显示中后场病灶可采用提高机械指数及局部放大等提高显示.  相似文献   
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