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目的 研究肺耐药蛋白(LRP)在食管鳞癌组织中的表达情况及其与临床病理特征和预后的关系。方法 应用Elivision二步免疫组织化学法观察51例食管鳞癌组织和18例癌旁正常粘膜组织(距离癌组织>2cm)中LRP的表达情况,结合临床病理指标包括患者年龄、肿瘤大小、临床分期和淋巴结转移以及生存情况进行统计学分析。结果 肿瘤大于5cm者LRP的阳性率明显高于5cm以下者(P<0. 05),食管鳞癌中LRP表达阳性率高于癌旁正常食管鳞状上皮,高年龄组的LRP阳性率较低年龄组高,有淋巴结转移者LRP阳性率高于无转移者,生存期短者( <3年)的阳性率高于生存期长者( >3年),但P均>0. 05。结论 LRP表达与食管鳞癌肿瘤大小之间存在显著相关性,临床检测LRP阳性不能作为判断食管鳞癌转移和预后的独立指标,但提示LRP表达阳性患者可能有预后差的趋势。  相似文献   
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目的:建立检测索他洛尔血药浓度的SPE-HPLC方法.方法:以C18固相萃取小柱预处理样品.色谱柱为Shim-pack VP-ODS C18柱,流动相为乙腈-水-三乙胺(5:95:0.2,v/v,磷酸调pH4.0),流速0.8 ml·min-1,柱温30℃,检测波长为227 nm,进样量20μl.结果:索他洛尔在0.04~5.0μg·ml-1浓度范围内线性关系良好,回归方程为Y=1.79X-0.02,r=0.999 8,索他洛尔萃取回收率为91.05%~100.75%,方法回收率为98.55%~101.36%(n=5),日内RSD小于5%,日间RSD小于10%.结论:本方法灵敏、准确,可用于索他洛尔的血药浓度检测.  相似文献   
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Purpose: The aim of the study was to investigate whether maternal serum TSP-1 level was associated with PE.

Materials and methods: In our case control study, 84 pregnant women in the third trimester were included. Forty-one of them were healthy and 43 of them were with the diagnosis of PE. The diagnosis was based on the definitions of the National High Blood Pressure Education Program working Group on High Blood Pressure in Pregnancy. Preeclamptic patients were divided into two subgroups as mild and severe. Blood pressure (BP) of pregnant women were obtained in left-side lying position using a mercury sphygmomanometer after at least 10 minutes of rest. Ten milliliters of venous blood was taken from every pregnant women and dispensed into lithium heparin and serum was obtained. Samples were stored at ?80?°C until analyzed. Serum TSP-1 level was measured using enzyme-linked immunosorbent assay (ELISA). All tests were two-tailed and p < .05 was considered to be statistically significant.

Results: TSP-1 level was significantly lower in PE group than in controls (p?=?.003). Platelet counts were similar in two groups (p = .26). TSP-1 levels were significantly lower in severe PE than in mild PE cases. According to the subgroup analysis, TSP-1 level was found significantly lower in severe preeclampsia group compared to control group (p = .015).

Conclusions: In light of the association between endothelial dysfunction and preeclampsia, we claim that lower levels of TSP-1 which is released mostly from endothelial cells seem to reflect disease severity in PE. Our study reveals that maternal serum TSP-1 levels decrease in pregnant women presenting with PE and TSP-1 may be a new biomarker for the detection of PE and even severity of it. Further studies especially prospective ones with greater numbers of cases are needed.  相似文献   
5.
神经肽Y(NPY)作为机体内一种主要的神经递质和能量调控因子,广泛参与机体各种生理功能的调节,是维持机体内环境稳态的重要物质之一。随着对其研究的不断深入,人们发现它可通过与特定靶细胞膜上不同NPY受体Y1-6的特异性结合而启动并激活相应细胞信号传导通路,从而参与对机体生理功能和靶细胞增殖分化的调控,且NPY及其受体在体内的表达水平又可影响机体的正常生理功能、细胞代谢活动、以及这种改变所诱导或促进或参与的某些老年性疾病的发生、发展及转归,并对相关药物的防治带来明显影响。因此,对NPY及其受体含量的检测项目已成为相关老年性疾病与合并症的发病机制分析、疾病进程观察、治疗效果评价、疾病痊愈判断及预后跟踪随访的重要辅助诊断指标之一。为此,本文通过对可用于老年基础医学研究与临床辅助诊断的NPY及其受体检测的酶联免疫吸附法、放射免疫测定法、荧光免疫检测法、化学发光免疫分析法、免疫组织化学法、压电石英晶片免疫传感器法、免疫印迹法、斑点免疫层析及胶体金法、受体放射配基结合分析法、放射自显影法、液体芯片技术、微粒子酶免分析法等进行NPY及其受体检测方法的综述,并提出前瞻性设想和设计,希望这些用于检测NPY及其受体指标的方法能为未来老年医学的研究和临床应用奠定基础。  相似文献   
6.
Lasers in Medical Science - The aim of this study was to assess the effect of two different laser systems on the mineral content of root canal dentin. Thirty-six single canal-extracted mandibular...  相似文献   
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Objectives: The aim of this study was to compare in vitro root fracture resistance following root canal filling with AH 26 using lateral condensation, BeeFill, and Thermafil techniques. Study Design: Eighty extracted human mandibular premolars with similar dimensions were selected. In order to standardize the roots, measurements were taken in two separate regions of the teeth—at the cemento-enamel junction and 8 mm apically from the junction—buccolingual as well as mesiodistal for every tooth. Teeth were then randomly divided into five groups (n=16). With the exception of the non-prepared group (Group 1), instrumentation was done in all groups. In group 2, instrumentation but no filling was performed; in group 3, the obturation was done with AH 26 + gutta-percha; in group 4, with AH 26 + BeeFill and in group 5, AH 26 + a Thermafil obturator was used. All the roots were mounted vertically in copper rings and filled with acrylic resin, exposing 8 mm of the coronal part. A universal testing machine was used for the strength test. Results: The results were analyzed using the one-way ANOVA test. The significance between the groups was tested with Temhane’s T2 test. The results indicate that instrumentation of root canals had a significant effect on fracture resistance (p<0.05). In addition, there were no differences between the root canal obturation techniques; furthermore, these techniques did not create a statistically important resistance to vertical fracture (p>0.05). Conclusions: The results suggest that instrumentation of root canals significantly weakens the tooth structure to fracture and the root canal obturation techniques that are used are not able to form reinforcement. Key words:AH 26, obturation technique, vertical fracture.  相似文献   
10.

Introduction

Near-infrared diode lasers can be used for several applications, which range from disinfection to smear layer removal in endodontics. This study evaluated the efficacy of agitation of 15% EDTA with an 808-nm diode laser on removal of the smear layer.

Methods

Sixty extracted human maxillary central incisor teeth were instrumented up to ProTaper F4 (Dentsply Maillefer, Ballagues, Switzerland) and then randomly divided into 6 groups (n = 10 for each group) according to the different final irrigating protocols as follows: 5% sodium hypochlorite for 120 seconds performed with the NaviTip (Dentsply Maillefer, Ballaigues, Switzerland) (control group); 15% EDTA for 120 seconds performed with the NaviTip; and agitation of 15% EDTA with an 808-nm diode laser for 10, 20, 30, and 40 seconds. Specimens were observed under a scanning electron microscope, and open dentinal tubules were counted using Adobe Photoshop software (Adobe Systems, San Jose, CA). The data were analyzed with 1-way analysis of variance and Tukey post hoc tests (P = .05).

Results

The number of open dentinal tubules was higher in the middle thirds than in the apical thirds. The differences between the apical and middle thirds were statistically significant (P < .05). Statistically significant differences were also found between the control group and the other groups in both the middle and apical thirds of the root canals (P < .05).

Conclusions

The results indicated that agitation of 15% EDTA with an 808-nm diode laser for 20 seconds was effective in removing the smear layer in the apical thirds of root canals.  相似文献   
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