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81.
目的:探索成人脂肪组织来源的间充质干细胞(ADMSCs)体外分离、培养方法,并化学诱导使其向心肌细胞分化,为心肌再生医学提供理想的种子细胞来源. 方法:体外分离成人ADMSCs并进行传代培养,5-氮胞苷(5-aza)诱导其向心肌细胞分化. 分别于诱导后14,21,28 d时用免疫细胞化学染色、RT-PCR法进行心肌细胞鉴定. 结果:ADMSCs经5-aza诱导后14 d时细胞形态趋向于心肌细胞,诱导28 d免疫细胞化学显示心肌特异性肌钙蛋白I(cTN-I)、结蛋白(Desmin)表达阳性,RT-PCR检测心肌β-肌球蛋白重链(Cardiac β-MHC)基因表达阳性. 结论:成人脂肪组织存在丰富的间充质干细胞且易于分离扩增,体外5-aza诱导可使其向心肌细胞分化,可做为心肌再生医学的理想种子细胞. 相似文献
82.
中药灯盏细辛中酚酸类化合物的结构与活性研究 总被引:20,自引:0,他引:20
目的 研究中药灯盏细辛的化学成分。方法 利用硅胶柱层析等分离手段从灯盏细辛[Erigeron breviscapus(Vant.)Hand-Mazz]的醋酸乙酯部位分离得到2个化合物,采用波谱方法(IR,MS,^1H-NMR,^13C-NMR,2D-NMR)鉴定了它们的结构。结果 2个酚酸类化合物分别为:5-O-咖啡酰基-奎宁酸甲酯(I)和4-O-咖啡酰基-奎宁酸甲酯(Ⅱ),结论 化合物Ⅰ,Ⅱ为首次从灯盏细辛中分得的酚酸类化合物。药理活性研究显示,化合物Ⅰ,Ⅱ可明显抑制VEGF诱导的血管高通透性(P<0.001)。 相似文献
83.
①目的探讨体外受精-胚胎移植(IVF-ET)足月妊娠胎盘中表皮生长因子受体(EGFR)的表达及其变化。②方法取IVF-ET足月分娩的胎盘组织标本30例,并以30例相同孕周自然妊娠分娩的胎盘组织标本为对照组,应用免疫组织化学SP法染色,通过Fromowitz综合计分法检测EGFR。③结果EGFR主要表达于胎盘的合体滋养细胞(ST)的胞膜和胞浆中,染色强度以刷状缘最强,IVF-ET组胎盘EGFR染色强度较正常对照组增强,差异有统计学意义(P<0.05);IVF-ET组胎盘重量和新生儿体重与正常对照组比较,无显著性差异(P>0.05);新生儿出生体重与胎盘重量呈高度相关性(r=0.709,P<0.01)。④结论IVF-ET组胎盘EGFR表达增强,可能与COH药物作用或黄体支持中母体体内超生理剂量孕酮的作用有关。 相似文献
84.
目的:应用二维及频谱多普勒检测甲状腺肿瘤血管,并进行分析,探讨其在甲状腺肿瘤诊断和鉴别诊断中的价值,更好地为临床服务。方法:入选35例甲状腺良性肿瘤(结甲21例,腺瘤14例)和21例甲状腺癌患者术前均行二维及频谱多普勒检查,包括最高流速(Vmax),阻力指数(RI)。对良恶性肿瘤的二维图像特征及血流动力学参数差异进行分析。结果:甲状腺良恶性肿瘤的二维图像特征及血流动力学参数(Vmax、RI)存在极显著差异(P<0.01)。结论:二维及频谱多普勒对鉴别甲状腺良恶性肿瘤具有重要意义。 相似文献
85.
【目的】总结研究急诊医护人员在心肺复苏无困难情况下实施即时气管插管的重要性。【方法】对107例心肺复苏患者随机分为治疗组为无困难插管组(即时插管)54例和对照组为困难插管组(延时插管)53例,通过观察两组患者心肺复苏成功率与存活率,比较即时插管与延时插管的救治效果。【结果】即时插管的患者心肺复苏的成功率为40.7%,存活率为18.5%;延时插管的患者心肺复苏的成功率为11.3%,存活率为1.9%,两组相比较差异显著(P〈0.05)。【结论】急诊医护人员在心肺复苏患者咽部无障碍的情况下即时气管插管可提高心肺复苏的成功率与患者的存活率。 相似文献
86.
针对视频格式的医学超声图像序列,提出了一种同时利用空间域、灰度域和时间域的相关信息的三域滤波算法。首先对每一帧图像,充分利用空间域和灰度域的相关信息构建自适应邻域,接着进行空间域和灰度域加权滤波,最后利用相邻帧之间的时域相关性进行时域加权滤波。三个域的滤波均采用高斯核函数加权,从而减小了滤波结果对阈值选取的敏感度,提高了算法的稳定性。实验结果表明,三域滤波算法能有效地抑制图像中的噪声,并保留边缘细节,有利于图像的特征提取、识别和分析。 相似文献
87.
Increased risk of leukaemia in patients with juvenile chronic arthritis treated with chlorambucil 总被引:2,自引:0,他引:2
MJ Kauppi HA Savolainen V-J Anttila HA Isomäki 《Acta paediatrica (Oslo, Norway : 1992)》1996,85(2):248-250
Two cases of acute leukaemia have developed in a group of 77 patients treated with chlorambucil (Chl) because of severe juvenile chronic arthritis. The total follow-up from the beginning of Chl treatment in these patients was 560 years, indicating a highly increased risk of leukaemia. Despite favourable results, especially in patients with secondary amyloidosis, Chl should only be used in selected cases. 相似文献
88.
Prevalence and aetiology of neurological impairment in extremely low birthweight infants 总被引:2,自引:0,他引:2
J WAUGH MJ O'CALLAGHAN DI TUDEHOPE HA MOHAY YR BURNS PH GRAY YM ROGERS 《Journal of paediatrics and child health》1996,32(2):120-124
Objective : To determine the prevalence and perinatal predictors of cerebral palsy, intellectual impairment, visual impairment and deafness in a cohort of extremely low birthweight (ELBW) infants at two years of age.
Methodology : The study population comprised 199 of the 224 (89%) ELBW infants managed at the Mater's Mothers Hospital, Brisbane, between July 1977 and February 1990 and who survived to two years. The prevalence of cerebral palsy, intellectual impairment, blindness and deafness was measured by clinical, psychometric and audiological assessment and the association with 24 risk factors examined.
Results : Cerebral palsy occurred in 20 children (10%). Risk of cerebral palsy was associated with ventricular dilatation, intraventricular haemorrhage, necrotizing enterocolitis and multiple birth, though only ventricular dilatation (OR 4.41; 95% Cl 1.32-14.8) remained significant in the adjusted analysis. Intellectual impairment occurred in 20 children (10%) and was independently associated with ventricular dilatation (OR 15.0; 95% Cl 2.2-102.8), ventilation Fi O2 >80% (OR 3.4; 95% Cl 1.01-11.5), vaginal delivery (OR 3.5; 95% Cl 1.09-11.4) and male sex (OR 6.1; 95% Cl 1.67-22.3). No perinatal predictor was statistically associated with risk of deafness. Retinopathy of prematurity (OR 36.9; 95% Cl 2.8-495.5) was associated with risk of later visual impairment.
Conclusions : Intellectual impairment was associated with a broad range of perinatal variables. Cerebral palsy was associated with fewer variables, all of which were also associated with intellectual impairment. Neurologic injury was associated with male sex and multiple birth, which are not biological insults themselves, but may be markers of susceptibility to injury. 相似文献
Methodology : The study population comprised 199 of the 224 (89%) ELBW infants managed at the Mater's Mothers Hospital, Brisbane, between July 1977 and February 1990 and who survived to two years. The prevalence of cerebral palsy, intellectual impairment, blindness and deafness was measured by clinical, psychometric and audiological assessment and the association with 24 risk factors examined.
Results : Cerebral palsy occurred in 20 children (10%). Risk of cerebral palsy was associated with ventricular dilatation, intraventricular haemorrhage, necrotizing enterocolitis and multiple birth, though only ventricular dilatation (OR 4.41; 95% Cl 1.32-14.8) remained significant in the adjusted analysis. Intellectual impairment occurred in 20 children (10%) and was independently associated with ventricular dilatation (OR 15.0; 95% Cl 2.2-102.8), ventilation F
Conclusions : Intellectual impairment was associated with a broad range of perinatal variables. Cerebral palsy was associated with fewer variables, all of which were also associated with intellectual impairment. Neurologic injury was associated with male sex and multiple birth, which are not biological insults themselves, but may be markers of susceptibility to injury. 相似文献
89.
HA Heij RA Nievelstein I de Zwart BW Verbeeten J Valk A Vos 《Archives of disease in childhood》1996,74(5):441-444
OBJECTIVE: To investigate the frequency of lumbosacral anomalies, the association with urogenital abnormalities, and the correlation with defaecation pattern by magnetic resonance imaging (MRI). METHODS: A prospective analysis was performed of routine MRI in patients with anorectal malformations. Between 1990 and 1994, MRI was performed in 43 such patients: 31 boys and 12 girls. Twenty four had a high anorectal malformation, 16 had a low anorectal malformation, and three had Currarino's triad. MRI was performed before reconstruction in 26, and postoperatively in 17. Urogenital anomalies were found in 21. RESULTS: Abnormalities of the spinal cord and spine were found with MRI in 20 patients (46.5%); caudal regression syndrome in 10, tethered cord in two, a combination of both in three, and other spinal anomalies in five. These anomalies were found in 30% of the patients with low anorectal malformations, and in 50% with high anorectal malformations. In patients with urogenital malformations, MRI more often showed spinal anomalies (13/21, 62%) than in patients without (7/22, 32%). In high anorectal malformations, defaecation was more often a problem in patients with spinal anomalies (12/15, 80%) than in patients without (2/8, 25%). CONCLUSIONS: Spinal anomalies in the lumbosacral region were found with MRI in 46.5% of patients with anorectal malformations. Since presence of these anomalies seems to be related to clinical outcome, MRI should be performed routinely in all such patients. 相似文献
90.
Twenty nine patients, aged 5-16 years, were studied to evaluate whether biofeedback training is effective in treating children with chronic constipation and encopresis; the clinical outcome at six weeks and 12 months was also evaluated. Patients received on average five biofeedback training sessions. The existence of external anal contraction or decreased rectal sensation in 16 (55%) and eight (27%) of the children, respectively was identified on manometry. After biofeedback training, 26 (90%) of the patients learned to relax the external anal sphincter; 18 (63%) normalised rectal sensation. The training resulted in a significant increase in defecation frequency and a significant decrease in encopresis. At six weeks, 16 (55%) of the patients were clinically symptom free. At follow up after 12 months the results were sustained. Only three patients showed a relapse within six months, of whom two were successfully treated with one extra training session. Biofeedback training might be a useful therapeutical approach in children with chronic constipation and encopresis. 相似文献