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71.
大鼠骨髓间充质干细胞与多孔双相磷酸钙陶瓷支架体外黏附的实验研究 总被引:4,自引:0,他引:4
目的研究大鼠骨髓间充质干细胞(marrowmesenchymalstemcells,MSCs)诱导培养后在多孔双相磷酸钙(biphasiccalciumphosphate,BCP)陶瓷支架材料上的黏附和生长。方法SD大鼠MSCs经矿化诱导培养、扩增,具有成骨细胞表型后,与多孔BCP陶瓷支架及普通多孔羟基磷灰石(hydroxyapatite,HA)陶瓷支架体外复合培养,扫描电镜观察比较MSCs在两种材料支架表面的黏附数量和形态;同时以0.5、1.0、2.0、3.0和4.0×106/ml浓度细胞悬液接种于多孔BCP支架材料,检测适宜的接种浓度及单位体积支架材料可黏附MSCs数量。结果大鼠MSCs经诱导培养14d后,行矿化沉积茜素红染色、型胶原免疫细胞化学染色及碱性磷酸酶细胞化学染色,结果均为阳性。大鼠MSCs黏附于多孔BCP陶瓷上的细胞数(88.00±6.58)明显高于HA陶瓷组(39.00±3.65),两组比较差异有统计学意义(P<0.01)。当接种浓度为2.0×106/ml时,单位体积的陶瓷支架材料最多可黏附MSCs数量为1.28×107个/cm3,为细胞适宜接种浓度。结论大鼠MSCs在体外经矿化诱导培养可表达成骨细胞表型,细胞浓度为2.0×106/ml时与多孔BCP陶瓷支架材料具有良好的黏附能力。 相似文献
72.
ALBERTO Q FARIAS LUCIANA L GONÇALVES EDUARDO LR CANÇADO ANTONIO C SEGURO SILVIA B CAMPOS CLARICE P ABRANTES-LEMOS FLAIR J CARRILHO 《Journal of gastroenterology and hepatology》2006,20(1):147-152
Background and Aims: Primary biliary cirrhosis (PBC) might be complicated by osteoporosis, whose etiology remains unknown but seems to be multifactorial. Prevalence rates of 30% to 60% for distal renal tubular acidosis (DRTA) have been reported in PBC patients, generally as incomplete DRTA. Although it is undisputed that a reduced bone mineral density (BMD) is the expected outcome among patients who have been suffering from longstanding chronic metabolic acidosis, it is unclear if incomplete DRTA is also associated with metabolic bone disease in PBC patients. The present study was undertaken to compare the BMD of PBC patients with and without DRTA.
Methods: The BMD of 23 PBC patients (11 with DRTA and 12 without), all with normal clearance of creatinine, was assessed by dual energy radiograph absorptiometry. The diagnosis of DRTA was made if the urine pH was above 5.4 in all samples after the oral acid overload, showing tubular inability to acidify urine in the presence of test-induced systemic metabolic acidosis.
Results: Densitometric signs of osteoporosis were found in 82% of DRTA cases and in 83% of patients without DRTA (difference not significant). There were no significant differences in BMD measurement, T and Z scores of patients with and without DRTA.
Conclusions: The present study could not support a correlation between the presence of DRTA and the bone loss observed in PBC patients. 相似文献
Methods: The BMD of 23 PBC patients (11 with DRTA and 12 without), all with normal clearance of creatinine, was assessed by dual energy radiograph absorptiometry. The diagnosis of DRTA was made if the urine pH was above 5.4 in all samples after the oral acid overload, showing tubular inability to acidify urine in the presence of test-induced systemic metabolic acidosis.
Results: Densitometric signs of osteoporosis were found in 82% of DRTA cases and in 83% of patients without DRTA (difference not significant). There were no significant differences in BMD measurement, T and Z scores of patients with and without DRTA.
Conclusions: The present study could not support a correlation between the presence of DRTA and the bone loss observed in PBC patients. 相似文献
73.
放射治疗71例骨转移癌止痛效果分析 总被引:2,自引:0,他引:2
目的观察低于常规剂量的2种分割方式治疗骨转移性疼痛的疗效。方法71例恶性肿瘤晚期骨转移患者,总计93处骨转移灶,根据疼痛程度及行动受限程度,采取2种均低于常规剂量的分割方式进行放射治疗,分别为Dm30Gy/10f/2W,Dm30Gy/6f/2W。观察疼痛缓解情况。结果2种分割方式止痛有效率分别为88%、95%。两组间无显著差异性(P>0.05)。与国内多数文献报告的结果接近。结论低于常规剂量的分割方式对转移性骨痛疗效与常规剂量的分割方式的疗效相当,且简便易行。 相似文献
74.
肝病患者血清诱导间充质干细胞表达肝细胞特异性标志物的实验研究 总被引:3,自引:0,他引:3
目的:观察重型肝病患者血清对人骨髓间充质干细胞(MSCs)的诱导分化作用,探讨人MSCs分离培养、体外扩增的条件和方法。方法:从肋骨分离、培养人骨髓MSCs、体外扩增培养、鉴定,并采用重型肝病患者血清诱导培养,分别在诱导培养0、7、14、21、28天时留取细胞,并采用免疫细胞化学方法检测肝特异性标志物(AFP、Alb、CK-18)、用PAS进行糖原染色实验。结果:诱导后5天、MSCs表现为肝细胞样细胞,随着诱导培养时间的延长,肝特异性标志物逐渐出现和成熟。AFP在7天时表达水平最高,培养14、21、28天时表达逐渐减弱;Alb、CK- 18和糖原随着诱导时间的延长,表达逐渐增强。结论:密度梯度离心,贴壁培养和消化时间控制相结合,是一种较为有效的分离纯化方法。重型肝病患者血清能诱导骨髓MSCs表达肝细胞的特异性标志物。 相似文献
75.
Statin, a HMG-CoA reductase inhibitor, was shown to increase BMP-2 gene expression for bone formation, by blocking the mevalonate pathway in cholesterol production. We investigated the effect of naringin, a flavonoid available commonly in citrus fruits, which was also a HMG-CoA reductase inhibitor, in UMR 106 osteoblastic cell line in vitro. The control group consisted of cells cultured without any intervention for different time intervals (24 h, 48 h, and 72 h), whereas the experimental (naringin) group consisted of cells cultured with naringin of different concentrations (0.001 micromol/L, 0.01 micromol/L, and 0.1 micromol/L) for the same time intervals of the control. Colorimetric Tetrazolium (MTT) assay, total protein content assay, and alkaline phosphatase activity were used to measure the cellular activities. Results for the naringin group showed an increase in MTT assay compared with the control and the effect was dose dependent. At high concentration (0.1 micromol), the increases ranged from 60% to 80%. In the total protein content assay, naringin also showed an increase compared with control and the effect was also dose dependent. At high concentration (0.1 micromol), the increases ranged from 9% to 20%. In the alkaline phosphatase activity assay, naringin at high concentration (0.1 micromol) significantly increased the activity up to 20%. In conclusion, naringin significantly increased bone cell activities in vitro. This is the first study specifically attempted to investigate the effect of naringin on bone cell activities. Besides statin, this provided another example of mevalonate pathway blockage in the cholesterol production pathway by HMG-CoA reductase inhibition will increase the bone cell activities. 相似文献
76.
李元华 《菏泽医学专科学校学报》2003,15(4):7-8
目的 探讨Graves患者骨生化标志的改变。方法 对38例Graves患者进行血AKP、Ca、P、ICTP、DPD、BGP、U-HOP/Cr及BMD测定。结果 Graves组的BMD显著低于正常对照组(P<0.01),Ca、ICTP、DPD、BCP、U-HOP/Cr显著高于对照组,Graves组的BMD与ICTP和DPD,BGP有很好的相关性(r=0.36,r=0527、r=0.401)。结论 Graves组骨吸收增加,骨形成减少。 相似文献
77.
The light microscopic and polarization appearances of calcium pyrophosphate dihydrate crystal deposits in tissues are reviewed. In routine sections haematoxylinophilic crystalline deposits with a feathery or brush-like pattern are typical of calcium pyrophosphate dihydrate. Short rhomboidal crystals showing positive birefringence are seen on polarization; X-ray microanalytical and infrared spectroscopic data support the specificity of these appearances. The appearances of the crystal deposits in decalcified specimens are also described. We include six cases of calcium pyrophosphate dihydrate deposition within periarticular bone; to the best of our knowledge this has not previously been described. 相似文献
78.
董剑桥 《南通大学学报(哲学社会科学版)》2004,20(3):84-88
线性文本与超文本的区别,不只在于文本的结构方式、技术实现方式、阅读写作方式和存储记忆方式等方面,还在于文本的媒体表现方式.狭义的超文本,意指跨越文本局限、打破线性结构的语篇组织方式;广义的超文本,则是指运用超文本标示语言(HTML),经数字化编辑而成的包括文本、音乐、图像、动画、影视等一切表意媒体的信息集合(超文本语篇).因此,超文本连贯性,除了具有线性文本的特征,更有其自身的特点,以视觉原理为基础的数字化修辞手段便是主要手段之一. 相似文献
79.
Objective: To prepare hydroxyapatite cement (or calcium phosphate cement,CPC) and analyze its capability. Methods: Tetracalcium phospluge (TTCP ) was prepared by the method of high heat. TTCP reacted with in simulated body situation and produced CPC. Its capability was analyzed by scanning electron microscopy ( SEM), X-ray diffraction( XRD). Its density, absorbing water coefficient, macroporosity and compressive strength were measured also. Results: The main element of CPC is hydroxyapatile (HA), its microstructure comprised of petal crys-tals. The diameter of micropore was 4-10μm, density was 1. 922 g/cm^3, macroporosity was 29. 777%, absorbing coefficient was 15. 503%, compressive strength was 42.70 Mpa. Conclusion: This CPC has three-dimensional spatial structure, its strength meets the need of cancellous bone grafting. 相似文献
80.
目的:观察自体干细胞动员对骨创伤大鼠的免疫功能的保护作用,为战创伤后的免疫抑制及继发性感染、系统性炎症反应等治疗提供依据。方法:挤压折断法复制大鼠双后肢股骨骨折模型,于致伤后0、24、48h连续给模型动物肌肉注射GM—CSF20μg/kg,致伤后72h细胞增殖法检测T、B淋巴细胞活性,ELISA法检测血清IL-1、IL-2、IFN-7、TNF—α浓度,自动系列化分析法检测C3、CA、IgM、IgG浓度,称重法观察脾重与体重的比例变化。结果:股骨骨折模型大鼠致伤后72h,GM—CSF动员骨髓干细胞组大鼠的T、B淋巴细胞活性和血清IFN-γ、IL-2浓度高于对照组(P〈0.01),IL-1、TNF—α浓度低于对照组(P〈0.01),血清C3、CA、IgM、IgG浓度及脾/体重比值高于对照组(P〈0.01)。结论:GM—CSF动员自体干细胞动员对大鼠骨创伤诱导的免疫功能抑制具有保护作用。 相似文献