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Sandra Urdaneta Hartmann Brian Wigdahl Elizabeth B Neely Cheston M Berlin Cara-Lynne Schengrund Hung-Mo Lin Mary K Howett 《Journal of human lactation》2006,22(1):61-74
Reduction of transmission of human immunodeficiency virus type 1 (HIV-1) through human milk is needed. Alkyl sulfates such as sodium dodecyl sulfate (SDS) are microbicidal against HIV-1 at low concentrations, have little to no toxicity, and are inexpensive. The authors have reported that treatment of HIV-1-infected human milk with < or = 1% (10 mg/mL) SDS for 10 minutes inactivates cell-free and cell-associated virus. The SDS can be removed with a commercially available resin after treatment without recovery of viral infectivity. In this article, the authors report results of selective biochemical analyses (ie, protein, immunoglobulins, lipids, cells, and electrolytes) of human milk subjected to SDS treatment and removal. The SDS treatment or removal had no significant effects on the milk components studied. Therefore, the use of alkyl sulfate microbicides to treat milk from HIV-1-positive women may be a simple, practical, and nutritionally sound way to prevent or reduce transmission of HIV-1 while still feeding with mother's own milk. 相似文献
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Ki-Won Kim Kee-Yong Ha Jun-Seok Lee Suk-Woo Nam Young-Kyun Woo Tae-Hong Lim Howard S. An 《The spine journal》2009,9(4):323-329
Background contextIt was recently demonstrated that the postnatal transition from a notochordal to a fibrocartilaginous nucleus pulposus (NP) is accomplished exogenously by chondrocytes migrating from hyaline cartilage end plates (CEs) into the ectopic notochordal NP region. Although our previous in vivo studies showed evidences for the migration of CE chondrocyte from hyaline CEs into the notochordal NP, it is unknown whether CE chondrocytes of the intervertebral disc (IVD) really have a motile property. In addition, the effect of notochordal cells on this property has not been elucidated.PurposeThe purpose of this in vitro study was to demonstrate whether CE chondrocytes of the IVD are capable of migration, and whether there is any biological link between notochordal cells and CE chondrocytes that may regulate the CE chondrocyte migration.Study design/settingIn vitro cell migration assays were performed using rat IVDs.MethodsNotochordal cells and chondrocytes were obtained from the NP and CE tissues, respectively, and were cultured separately. The different numbers of notochordal cells and the supernatant (conditioned medium) that contained soluble factors produced by notochordal cells were used to demonstrate their effects on the migration of CE chondrocytes. Bovine serum albumin (BSA) and lysophosphatidic acid (LPA) were used as negative and positive controls, respectively.ResultsCompared with BSA, LPA, notochordal cells (N=4×, 2×, 1×, and 0.5×105), and its conditioned media (unconcentrated and fivefold concentrated) significantly increased migration of CE chondrocytes (p<.05 in all comparisons). Particularly, notochordal cells and its conditioned media increased migration in a number- and concentration-dependent manner, respectively.ConclusionsThis study demonstrates that CE chondrocytes of the IVD are capable of migration and that soluble factors produced by notochordal cells stimulate the migration. These results provide a plausible explanation to the question of why CE chondrocytes of the IVD migrate into the ectopic NP region during the natural transition from the notochordal to fibrocartilaginous NP. 相似文献
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The neutral lipids existing in the intercellular spaces of the stratum corneum (SC) provide a permeability barrier to prevent water loss. Nile red is the most sensitive lipid stain for tissue sections. However, due to the extremely flattened morphology of corneocytes and the resolution limits of the light microscope, Nile red staining is seldom used as a fluorescent probe for the lipid-rich SC. In this study, we modified the traditional method for visualization of intracellular lipid by adding 4% potassium hydroxide after Nile red staining. This modified method not only allowed visualization of lipids existing in the intercellular membrane regions and the lateral junctions of the adjoining corneocytes, but also clearly demonstrated small lipid droplets within pathological corneocytes. These features were not observed with the traditional staining method. Thus, this modified Nile red staining method greatly improved the resolution of the SC lipids under light microscopy and should be useful for studying lipid depositions in both normal and pathological SC. 相似文献
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目的探讨Le Fort型骨折的CT表现及其分型。方法对62例Le Fort型骨折患者进行薄层螺旋CT扫描和三维重组分析。结果在62例中,Le FortⅠ型10例,Ⅱ型9例,Ⅲ型8例,复合型35例(其中Ⅰ+Ⅱ型18例,I+Ⅱ+Ⅲ型7例,Ⅱ+Ⅲ型10例);55例同时伴发颌面部其他骨折。Le Fort型骨折在二维CT上表现为颌面部多发且杂乱的骨折,虽然在发现细小和深部结构的骨折方面优于三维CT成像,但难以作出Le Fort型骨折的诊断;三维CT成像能清晰立体地显示Le Fort型骨折的整体形状及走向,并可明确作出分型。结论三维CT成像是Le Fort型骨折最有效的诊断方法,对临床制定治疗方案具有指导意义,但是对细小骨折诊断不如二维CT。 相似文献
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目的评价珊瑚人工骨的遗传毒性。方法采用Ames试验;细胞染色体畸变试验和小鼠骨髓细胞微核试验。结果不同浓度的浸提液加与不加S9mix条件下Ames试验;细胞染色体畸变试验以及微核试验与阴性对照组比较无显著差异,结果为阴性。结论在本试验系统条件下,可吸收性珊瑚人工骨无致突变作用。 相似文献
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目的观察半乳糖化白蛋白磁性阿霉素纳米粒(ADR-GHMN)在正常肝脏中的靶向性,并观察ADR-GHMN在全身各脏器的分布特征及外加磁场对其分布的影响.方法大鼠正中开腹,肝动脉插管并固定,肝动脉注射125I-ADR-GHMN(相当于阿霉素0.5 mg/kg),左外叶加磁场,磁场应用30 min,移去磁场后,动物立即处死;对照组:肝动脉注射ADR-GHMN,左外叶不加磁场,30min后,移去磁场后,动物立即处死,立即取靶区肝、非靶区肝、肾、心、肺、小肠、脾及周围血作γ计数.肝组织作病理切片.结果注入的纳米粒75~85%分布于肝脏,其它脏器极少.病理切片显示磁区小动脉见大量纳米粒存在,对照组及非磁区肝中纳米粒很少见.结论ADR-GHMN在正常肝组织中有明显的磁靶向性;在磁场作用下,ADR-GHMN主要分布于肝脏,其它脏器含量很少;试验组肾、心、肺、小肠、脾及外周血于对照组的放射活性比较明显降低,表明磁性物质的存在使这些脏器的相对药物暴露明显减少. 相似文献
50.
平板运动试验阴性患者最大ST/HR斜率对冠心病的诊断价值 总被引:3,自引:1,他引:2
目的探讨平板运动试验阴性患者最大ST/HR斜率对冠心病的诊断价值.方法选择122例平板运动试验阴性而临床有明显冠心病指征的患者进行冠状动脉造影,测定其最大ST/HR斜率.结果平板运动试验阴性患者最大ST/HR斜率诊断冠心病的敏感性为68.2%,特异性为80.8%,准确性为76.2%;运动峰值心率<预计最大心率之85%组最大ST/HR斜率诊断冠心病的敏感性为92.8%,特异性为86.7%,准确性为89.7%,高于运动峰值心率≥预计最大心率之85%组.结论平板运动试验阴性患者最大ST/HR斜率对冠心病的临床诊断有较高的敏感性、特异性和准确性,尤其是对低运动水平的患者,对减少运动试验诊断的漏诊率具有重要意义. 相似文献