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51.
杜红延  王捷  郭勇  郑霖  杨静 《中国临床康复》2005,9(38):152-154,i0005
背景:人骨唾液蛋白基因在矿化组织以外的易发生骨转移的人乳腺癌中表达。临床观察显示骨转移处的乳腺癌细胞骨唾液蛋白的表达量要高于原发部位的乳腺癌细胞,因此骨唾液蛋白有可能与肿瘤特异性骨转移的关系密切。研究乳腺癌骨转移可为将来临床的预防和治疗提供新的药物靶点。目的:建立骨唾液蛋白的稳定表达乳腺癌细胞系,观察骨唾液蛋白在乳腺癌骨转移的整个过程中的作用。设计:对照实验。单位:华南理工大学生物科学与工程学院,解放军广州军区广州总医院医学实验中心。材料:实验于2003-11/2004-03在解放军广州军区广州总医院医学实验室完成。质粒、菌种和细胞:pIRES2-EGFP载体质粒,E.Coli.Top10、含有人骨唾液蛋白基因全长的克隆载体pB-hBSP和发生特异性骨转移以及脑转移的人乳腺癌细胞株MDA-MB-231BO和MDA-MB-23lBR。方法:将人骨唾液蛋白基因通过聚合酶链式反应的方法从构建好的pB-hBSP载体中亚克隆出来,在其5’和3’端分别引入BglⅡ和PsiⅠ限制性酶切位点,定向克隆至真核表达载体pIRES2-EGFP,构建重组载体pIRES2-hBSP-EGFP。利用脂质体转染的方法将构建好的重组质粒转入特异性脑转移和骨转移的乳腺癌细胞株MDA-MB-231BR和MDA-MB-231BO中。主要观察指标:pIRES2-hBSP-EGFP重组表达载体的构建。重组表达载体pIRES2-hBSP-EGFP转染乳腺癌细胞。结果:①成功构建人骨唾液蛋白和绿色荧光蛋白非融合表达的真核表达载体pIRES2-hBSP-EGFP。②成功转染特异骨转移和脑转移的乳腺癌细胞株,可在荧光显微镜下观察到荧光蛋白标记,人骨唾液蛋白得到相应表达。结论:真核表达载体pIRES2-hBSP-EGFP的构建及转染可为骨唾液蛋白在乳腺癌骨转移中的作用的体内、外研究奠定一定的基础。  相似文献   
52.

Objective

This study was designed to identify the presence, type and origin of bacteria adjacent to the metal implant in the infected region in a canine model of pyogenic vertebral osteomyelitis treated with single-stage anterior autogenous bone grafting and instrumentation.

Methods

Dogs with pyogenic spondylodiscitis underwent one-stage debridement, autogenous bone grafting and titanium plate instrumentation and perioperative antibiotic therapy. The implants and adjacent vertebral bones were removed surgically at various postoperative time points (4, 8, 12 and 24 weeks) for bacteria detection. Bacteria were detected from retrieved spinal implants as well as surrounding bones by culture and/or pyrosequencing methods in 17 (85 %) of all 20 animals. The positive rate for bacteria presence was 45 % by culture and 80 % by pyrosequencing method.

Results

Radiological or macroscopic examination showed no signs for infection recurrence in any animal regardless of bacteria presence at the surgical site. However, organism identical with the causative bacterium for spinal infection was found in only two of nine culture-positive animals.

Conclusion

Within the confines of the study, the use of metallic implants in an infected area did not lead to a clinically relevant infection although bacteria may exist at the surgical site. The use of metallic implants in an infected area of the spine is safe. The metallic implants may not be the “culprit” for the persistence or recurrence of infection.  相似文献   
53.
Solid lipid nanoparticles for enhancing vinpocetine's oral bioavailability.   总被引:5,自引:0,他引:5  
An ultrasonic-solvent emulsification technique was adopted to prepare vinpocetine loaded Glyceryl monostearate (GMS) nanodispersions with narrow size distribution. To increase the lipid load the process was conducted at 50 degrees C, and in order to prepare nanoparticle using an ultrasonic-solvent emulsification technique. The mean particle size and droplet size distribution, drug loading capacity, drug entrapment efficiency (EE%), zeta potential, and long-term physical stability of the SLNs were investigated in detail respectively. Drug release from two sorts of VIN-SLN was studied using a dialysis bag method. A pharmacokinetic study was conducted in male rats after oral administration of 10 mg kg(-1) VIN in different formulations, it was found that the relative bioavailability of VIN in SLNs was significantly increased compared with that of the VIN solution. The amount of surfactant also had a marked effect on the oral absorption of VIN with SLN formulations. The absorption mechanism of the SLN formulations was also discussed. These results indicated that VIN absorption is enhanced significantly by employing SLN formulations. SLNs offer a new approach to improve the oral bioavailability of poorly soluble drugs.  相似文献   
54.
目的:应用红细胞酸性磷酸酶-腺苷脱氨酶-腺苷酸激酶同步电泳分型,从血型遗传学角度对粤西汉族血液中3种酶型的表型分布、基目频率进行调查。方法:实验于2005-03/11在湛江师范学院完成。①血样取自广东湛江地区无血缘关系的汉族健康成人120例,3代内无与外族通婚史。②120例汉族健康成人均取耳血一两滴,渗于无菌纱布上,血痕直径1cm,低温干燥保存,7~14d内进行血痕表型检测。③基因频率计算采用Hardy-Weinbery平衡计算法。种群中某基因频率(%)=种群中该基因总数/种群中该对等位基因总数×100%;种群中某基因型频率(%)=种群中该基因型个体数/该种群的个体数×100%。结果:实验血样取自广东湛江地区无血缘关系的汉族健康成人120例,全部进入结果分析。①粤西汉族酸性磷酸酶、腺苷脱氨酶、腺苷酸激酶3种酶型表现型的观察值与期望值基本吻合(P>0.05),检测的酶型中未发现稀有型、变异型,亦未发现罕见基因。②在粤西汉族群体中,酸性磷酸酶具有中高鉴别能力(积累能力值0.5043),腺苷脱氨酶为低鉴别能力(积累能力值0.2922),而腺苷酸激酶无鉴别能力(积累能力值0.0023)。结论:粤西汉族人群3种检测酶型中未发现稀有型、变异型,亦未发现罕见基因。符合Hardy-Weinbery遗传平衡定律。  相似文献   
55.
56.
57.

Objective

The present study aims to investigate the relationship between effort–reward imbalance and hair cortisol concentration among teachers to examine whether hair cortisol can be a biomarker of chronic work stress.

Methods

Hair samples were collected from 39 female teachers from three kindergartens. Cortisol was extracted from the hair samples with methanol, and cortisol concentrations were measured with high performance liquid chromatography–tandem mass spectrometry. Work stress was measured using the effort–reward imbalance scale.

Results

The ratio of effort to reward showed significantly positive association with hair cortisol concentration.

Conclusion

The cortisol concentration in the system increases with the effort–reward imbalance. Measurement of hair cortisol can become a useful biomarker of chronic work stress.  相似文献   
58.
59.

Introduction

Alveolar soft part sarcoma (ASPS), a rare soft tissue malignant neoplasm, frequently metastasizes to the brain. However, primary intracranial ASPS is extremely rare. We present a case of primary intracranial ASPS arising from the cerebellopontine angle (CPA) without demonstrable systemic lesions.

Case report

An 11-year-old girl presented with a recurrent tumor in the right CPA after a partial resection and radiation therapy (RT). Near-total resection with a minimal tumor left in the jugular foramen was performed. The pathological diagnosis was ASPS. There was no evidence of primary extracranial tumors. She underwent adjuvant chemotherapy and gamma knife surgery. At 29 months after the second surgery, magnetic resonance imaging revealed multifocal enhancing lesions at the prepontine cistern, right CPA and medulla oblongata, despite intensive treatment. However, extracranial metastasis was not noted. This case suggested a poor outcome of primary intracranial ASPS, similar to extracranial ASPS.  相似文献   
60.
The aim of this study was to evaluate whether contrast enhanced fluid attenuated inversion recovery (CE-FLAIR) imaging can be used to predict the severity of meningitis based on leptomeningeal enhancement (LE) score and cerebrospinal fluid signal intensity (CSF-SI) on CE-FLAIR. We retrospectively analyzed data collected from 43 consecutive patients admitted to our hospital due to meningitis. Clinical factors including initial Glasgow Coma Scale (GCS) score, CSF glucose ratio, log CSF protein, log CSF WBC, and prognosis were evaluated. The LE score was semi-quantitatively scored, and we evaluated CSF-SI ratio at the interpeduncular or quadrigerminal cisterns on CE-FLAIR. We evaluated the differences in clinical variables, LE scores and CSF-SI ratios between the recovery and the complication group. We assessed the correlation between clinical variables, LE scores and CSF-SI ratios. The values of log CSF protein, CSF-SI ratio, and LE score were significantly higher in the complication group (p value <0.05). GCS score and CSF glucose ratio were significantly lower in the complication group (p value <0.01). The LE scores had significant negative correlation with GCS scores and CSF glucose ratios (p value <0.001). The LE score was significantly positively correlated with the value of log CSF protein and CSF-SI ratio (p value <0.01). The CSF-SI ratio was negatively correlated with GCS score and CSF glucose ratio (p value <0.01). The CSF-SI ratio was positively correlated with the value of log CSF protein (p value <0.05). Our results suggest that LE score and CSF-SI ratio are well correlated with clinical prognostic factors. We may predict the clinical severity of meningitis by using LE scores and CSF-SI ration on CE-FLAIR imaging.  相似文献   
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