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Liu CY Westerlund U Svensson M Moe MC Varghese M Berg-Johnsen J Apuzzo ML Tirrell DA Langmoen IA 《Journal of hematotherapy & stem cell research》2003,12(6):689-699
Cellular transplantation therapy is thought to play a central role in the concept of restorative neurosurgery, which aims to restore function to the damaged nervous system. Stem cells represent a potentially renewable source of transplantable cells. However, control of the behavior of these cells, both in the process of clonogenic expansion and post-transplantation, represents formidable challenges. Stem cell behavior is thought to be directed by extracellular signals in their in vivo niches, many of which are protein or peptide based. As only one example, activation of Notch plays an important role in normal development and is the strongest known signal for stem cells to choose glial over neuronal fates. Therefore, artificial extracellular matrix proteins represent a potentially powerful tool to custom design artificial niches to strategically control stem cell behavior. We have developed a family of aECM proteins that incorporate the active domains of the DSL ligands to the Notch receptor into an elastin-based backbone. The development of our DSL-elastin artificial proteins demonstrates the design strategy and methodology for the production of bioactive artificial extracellular matrix proteins aimed at modulating stem cell behavior, and this method can be used to design other bioactive aECM proteins. In addition, we have developed a method for the isolation and characterization of adult human neural stem cells from periventricular tissue harvested from living patients. This paper reviews cellular transplantation therapy from the clinical perspective and summarizes ongoing work aimed at exploring the intriguing possibility of autologous transplantation, whereby neural stem cells can be harvested from adult patients, expanded or modified in vitro in artificial niches, and retransplanted into the original patient. 相似文献
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ML Harries JM Walker DM Williams S Hawkins IA Hughes 《Archives of disease in childhood》1997,77(5):445-447
The changes in the male voice in relation to the biological characteristics of puberty were assessed longitudinally in 26 boys. Speaking and singing fundamental frequencies were analysed in relation to the Tanner staging of puberty, saliva testosterone levels, and the Cooksey classification of voice analysis. There were abrupt changes in voice characteristics between Tanner stages G3 and G4 and more gradually from stages C3 to C5 of Cooksey. Although testosterone concentrations were not predictive of the changes, there was a correlation with testis volume. Voice fundamental frequencies were seen to change abruptly in late puberty, in contrast with previous studies. There is a good correlation between the Tanner and Cooksey methods of classification during male puberty. 相似文献
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Endothelial nitric oxide synthase in placental villous tissue from normal, pre-eclamptic and intrauterine growth restricted pregnancies 总被引:8,自引:1,他引:8
Myatt L; Eis AL; Brockman DE; Greer IA; Lyall F 《Human reproduction (Oxford, England)》1997,12(1):167-172
Nitric oxide (NO) regulates blood flow in the human placenta. As increased
resistance to blood flow is seen in the fetal-placental vasculature in
pregnancies complicated by pre-eclampsia and/or intrauterine growth
restriction (IUGR), we examined expression of endothelial nitric oxide
synthase (eNOS) in these placentas. Placental villous tissue sections were
obtained from normotensive control (n = 5), IUGR alone (n = 5) or
pre-eclamptic (with or without IUGR (n = 9) patients, immunostained for
eNOS and scored for localization, type (punctate or diffuse) and intensity
of eNOS staining in syncytiotrophoblast and placental vessels. The
significance of differences was calculated using the Mann-Whitney U-test.
No differences in intensity or type of immunostaining in
syncytiotrophoblast were seen. Placentas from patients with pre- eclampsia
with or without IUGR had a significantly more basal distribution of eNOS in
syncytiotrophoblast. eNOS immunostaining was absent in terminal villous
capillary and faint in stem villous vessel endothelium of normal placentas,
but was intense in the endothelium of both of these types of vessels in the
IUGR and pre-eclampsia groups, with significantly greater staining seen in
stem vessels of patients with IUGR alone. This increased eNOS expression
and hence increased NO production in the fetal-placental vasculature may be
an adaptive response to the increased resistance and poor perfusion in
these pathological pregnancies.
相似文献
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目的观察经皮腔内顺行球囊扩张结合内切开术治疗肾盂输尿管连接部梗阻(UPJO)的疗效。方法回顾分析2010年3月至2012年9月我院采用经皮腔内顺行球囊扩张结合内切开术治疗肾盂输尿管连接部梗阻23例患者的病例资料并行随访。结果患者23例,男性14例,女性9例;年龄21~71岁,平均(39±10.5)岁;左侧10例,右侧13例;原发性UPJO 18例(合并肾结石12例),经皮肾镜碎石术后2例,肾盂输尿管连接部结石开放取石术后1例,开放肾盂成形术后1例,腹腔镜肾盂成形术后1例,狭窄段长度均不超过2cm。所有患者均手术成功,围手术期无严重并发症发生。17例患者纳入随访,其中原发性UPJO患者12例,经皮肾穿刺取石术(PCN)术后患者2例,开放输尿管切开取石术后1例,腹腔镜下肾盂成形术后1例,开放肾盂成形术后1例,术后随访7~31月,未见复发。结论经皮腔内顺行球囊扩张结合内切开术是治疗UPJO安全、有效的手术方式,具有微创、患者耐受度好、术后恢复快的特点,可有选择性地作为治疗UPJO的初始治疗手段。 相似文献
110.
目的:探讨后腹腔镜技术与开放手术治疗上尿路移行细胞癌(upper urinary tract transitional cell carcinoma,UUT-TCC)的效果及优势。方法:回顾性分析2009年11月~2012年12月间,我院采用后腹腔镜下肾输尿管根治性切除术加腹膜后肾周区域淋巴结清扫术治疗肾盂输尿管癌患者23例(腹腔镜组),并与同期14例行传统开放性肾输尿管切除术患者(开放术组)的手术时间、出血量、肿瘤学预后等指标进行比较。结果:腹腔镜组患者经术后病理检查,肾盂癌24例,输尿管癌10例,输尿管癌伴膀胱癌3例,其中腹腔镜组和开放组淋巴结转移各1例。同时研究发现:①腹腔镜组与开放术组比较,手术时间缩短,出血量明显减少,术后肠胃功能恢复快,术后住院时间短,差异有统计学意义(P0.05);②两种术式肿瘤学预后在远处转移方面,腹腔镜组更少,差异有统计学意义(P0.05)。结论:后腹腔镜下肾输尿管全长切除加经尿道膀胱袖状切除并腹膜后肾周区域淋巴结清扫治疗UUT-TCC具有创伤小、痛苦少、术后恢复快等优点,可能有更好的肿瘤学预后。 相似文献