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Objective  The performance of colposcopy provided in a screening study in five African countries was evaluated.
Design  Cross-sectional study.
Setting  Burkina Faso, Congo Brazzaville, Guinea Conakry, Mali and Niger.
Population  Women aged 25–59 years.
Methods  A total of 29 294 women participated in a cervical screening study in the five study sites, and newly trained local doctors performed colposcopy and directed biopsies as indicated. Using meta-analytical tools, four measures of colposcopy performance at different thresholds of colposcopic abnormalities were assessed. Sources of heterogeneity were also assessed.
Main outcome measures  Proportions of women receiving biopsies, adequate biopsies and women diagnosed with cervical intraepithelial neoplasia (CIN).
Results  Among 28 553 women with satisfactory colposcopy, 3101 had a colposcopic diagnosis of probable low-grade or worse lesions and 1128 probable high-grade or worse lesions. Overall, the measures that reached the set standards were proportion of biopsy taken at colposcopy threshold of probable high-grade or worse lesions (95%, 95% CI 90–100%) and proportion of adequate biopsy samples. The set standards were not met for the proportions of women diagnosed with CIN at different colposcopic abnormality thresholds. Detection of CIN2 or worse lesions increased with increasing colposcopic abnormality.
Conclusions  The performance of colposcopy in some of the African sites studied was comparable to that previously observed in other studies. With appropriate training, monitoring, continuing practice and quality assurance, adequate standards of colposcopy can be attained in sub-Saharan Africa.  相似文献   
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The development of effective receptor-targeted nonviral vectors for use in vivo is complicated by a number of technical problems. One of these is the low efficiency of the conjugation procedures used to couple protein ligands to the DNA condensing carrier molecules. We have made and characterized a multi-domain protein (SPKR)4inv, that is designed to target plasmid DNA to beta1 integrins in remodeling tissue. It contains a nonspecific DNA-binding domain (SPKR)4, a rigid alpha-helical linker, and the C-terminal beta1 integrin binding domain (aa 793-987) of the Yersinia pseudotuberculosis invasin protein. (SPKR)4inv could be purified at high yields using a bacterial expression system. We show that (SPKR)4inv binds with high affinity to both plasmid DNA and beta1 integrins. In a cell attachment assay, the apparent affinity of (SPKR)4inv for beta1 integrins is three orders of magnitude higher than that of the synthetic peptide integrin ligand RGDS. (SPKR)4inv-plasmid complexes are not active in an in vitro transfection assay. However, transfection efficiencies of plasmid complexes with a cationic lipid micelle (DOTAP/Tween-20) or a cationic polymer (polyethylenimine), are significantly increased in combination with (SPKR)4inv. (SPKR)4inv-mediated transfection can be inhibited by a soluble form of beta1 integrin, which is evidence for its receptor specificity. In conclusion, (SPKR)4inv allows beta1 integrin-specific targeting of plasmid-carrier complexes, while avoiding inefficient and cumbersome coupling chemistry. The modular design of the expression vector allows production of similar multi-domain proteins with a different affinity. The further development of such complexes for use in vivo is discussed.  相似文献   
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目的:在缝合的基础上局部应用纤维蛋白胶治疗损伤的周围神经,观察纤维蛋白胶对周围神经再生的影响。方法:实验于2005-03/07在大连医科大学中心实验室完成。实验材料:纤维蛋白胶(广州倍绣生物技术有限公司,主要成分:纤维蛋白原50~70mg/支和凝血酶400U/支,从哺乳动物血中提纯,经过灭菌消毒,冻干制成,不含致热源)。实验分组:选择健康SD大鼠48只,按随机数字表法分为两组,每组24只:单纯缝合 纤维蛋白胶组、单纯缝合组。实验方法:大鼠麻醉后,于左大腿后外侧做2cm纵切口,显露坐骨神经。距梨状肌下缘远侧约1.5cm处切断坐骨神经,切除远端1~2mm,采用10-0无创伤线缝合神经外膜,使远近端保留约1~2mm间隙。单纯缝合 纤维蛋白胶组:对称缝合2针,将纤维蛋白胶注入缝合周围在神经对合端生成凝胶环,混合物固化形成再生室。单纯缝合组:单纯外膜缝合。实验评估:①术后连续观察动物行为学:手术侧后肢及足趾的运动情况,有无溃疡形成,足趾、趾甲的溃疡愈合情况,观察展爪反射。②术后8周两组各取4只大鼠行神经电生理检查,检测神经传导速度、潜伏期。③术后2,4,6,8周两组各取2只大鼠行苏木精-伊红染色后光镜下观察神经再生情况。④术后8周两组各取4只大鼠采用LUZEX-F彩色图像分析仪对甲苯胺蓝染色神经组织切片中轴突数目及轴突直径进行分析。⑤术后8周两组各取4只大鼠行醋酸铀枸橼酸铅染色,Phlip-10型透射电镜下观察轴突再生情况。⑥术后8周两组各取4只大鼠行辣根过氧化物酶标记观察脊髓前角运动神经元情况。结果:纳入大鼠48只,均进入结果分析。①术后大鼠行为学观察:术后8周单纯缝合 纤维蛋白胶组大鼠除足趾略见下垂、屈曲现象外,步态基本正常,展爪反射基本正常,下肢活动已接进正常,单纯缝合组下肢活动略差。②神经电生理检查:术后8周单纯缝合 纤维蛋白胶组神经传导速度快于单纯缝合组[分别为(11.13±0.37),(9.26±0.44)m/s],潜伏期短于单纯缝合组[分别为(1.83±0.18),(2.17±0.19)ms],差异有显著性意义(F=27.78,5.53,P<0.05)。③光镜下神经再生情况:单纯缝合 纤维蛋白胶组再生的有髓神经纤维髓鞘较厚、直径较大、数量多、排列规则,再生良好。单纯缝合组再生的有髓神经纤维髓鞘较薄、直径较小、数量少、排列不规则,再生较差。④轴突数目及轴突直径:单纯缝合 纤维蛋白胶组在轴突数目、轴突直径大于单纯缝合组[分别为(2187±107),(1847±96)个/400倍视野;(2.79±0.15),(2.05±0.17)μm],差异有显著性意义(F=80.70,42.92,P<0.05)。⑤透射电镜下轴突再生情况:术后8周单纯缝合 纤维蛋白胶组大鼠再生轴突发育良好,排列有序,轴突直径大小相差小,髓鞘厚薄一致,轴突染色均匀,雪旺细胞核呈卵圆型。单纯缝合组大鼠轴突发育差,排列不规则,髓鞘薄,可见扩张血管,部分区域有出血水肿。⑥辣根过氧化物酶标记观察脊髓前角运动神经元情况:单纯缝合 纤维蛋白胶组在实验侧腰骶段前角可见辣根过氧化物酶标记的大型运动神经元,且数目较多。单纯缝合组标记的数量较少。结论:在修复神经过程中应用纤维蛋白胶,可明显促进损伤的周围神经修复与再生,优于单纯缝合的效果。  相似文献   
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患儿,女,4岁,体质量19kg。生后4个月开始进行性面色苍白伴巩膜黄染,血红蛋白65g/L,白细胞和血小板均正常,血红蛋白电泳血红蛋白A48.1%、血红蛋白A24.2%、抗碱血红蛋白47.7%,基因型为β地贫纯合子,诊断为重型β地中海贫血,以间断大量输血维持生命。于2005-12-09在厦门大学附属中山医院血液科接受非亲缘性外周血干细胞移植。预处理方案采用常规氟达拉滨、白消胺、环磷酰胺三药联合方案,以环孢菌素A、霉酚酸酯、抗胸腺淋巴细胞免疫球蛋白联合预防移植物抗宿主病,供受者人类白细胞抗原高分辨全相合,ABO血型次要不合(O-A),输入CD34 干细胞11.4×106/kg。植入成功,移植后12d中性粒细胞>0.5×109L-1,移植后37d血小板>50×109L-1,移植后35d患者血型检测转变为供者血型,患儿血红蛋白达到100g/L的时间是28d,移植后患儿未再输血,血红蛋白维持130g/L以上,整个移植过程顺利,未出现严重感染和移植物抗宿主反应,随访18个月,患儿生活正常,发育良好。  相似文献   
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Previous studies of platelet membrane glycoproteins during blood bank storage have reported conflicting results. This study assessed two major plasma membrane glycoproteins (GP Ib and GP IIb), an alpha-granule membrane protein (GMP-140), and the concentration of platelet membrane microparticles in cell-free plasma during routine hospital blood bank platelet storage. 125I-monoclonal antibody binding was used to measure membrane glycoproteins on the surface of intact platelets and to measure the concentration of membrane microparticles in cell-free plasma. Platelet concentrates were stored at room temperature in polyolefin bags for 7 days. In this blood bank, two types of rotators are routinely used for platelet concentrate storage: a 2-rpm circular tumbler rotator and a 6-rpm elliptical rotator. Different results were obtained with the rotators. With the tumbler rotator, there was no loss of platelets and antibody binding to GP Ib remained normal. With the elliptical rotator, one third of platelets were lost into clumps during storage, and a 50 percent decrease of antibody binding to GP Ib occurred in the remaining single platelets. There was no loss of antibody binding to GP IIb with either rotator. Antibody binding to GMP-140 increased equally in both rotators indicating that the remaining single platelets had secreted about 16 percent of their alpha-granule contents. The plasma concentration of platelet membrane microparticles was greater in the bags stored in the elliptical rotator. These results indicate that it is possible to maintain the normal concentration of platelet membrane glycoproteins Ib and IIb during 7 days of room-temperature blood bank storage.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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A medicoeconomic evaluation of continuous intrathecal baclofen (Lioresal®) infusion for symptomatic treatment of severe spinal spasticity was realised using a monocentric, comparative, retrospective approach where subjects were their own controls (n = 22). Study results confirm the efficacy of baclofen on symptoms, functional status of patients and on a non specific quality of life scale. Conversely, use of baclofen lead to a 67% increase of average annual costs of care for these patients and reaches around 173,500 French francs (~29,000 US$)/year. Such a cost seems to be acceptable with respect to clinical benefits. © 1998 Elsevier, Paris  相似文献   
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