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61.
血清骨唾液酸蛋白的生物变异性研究   总被引:3,自引:0,他引:3       下载免费PDF全文
目的 骨唾液酸蛋白(Bone sialoprotein,简称BSP)是由成骨细胞分泌的一种非胶原蛋白质,反映骨转换和骨形成的指标。最近研究认为:血清BSP浓度可反映破骨细胞活性和骨吸收过程,也可能是一个骨吸收指标。本实验测定了血清BSP在人体内的生物变异性。方法 采用RIA 法测定了290例不同性别和年龄的正常人血清BSP的正常值,血清BSP的天-天变异性及24 h 生物周期。 结果 在儿童组血清BSP正常水平明显高于成人组,其最高值在新生儿期和青春期。绝经后妇女其血清浓度比绝经前妇女水平明显升高(P< 0.05)。血清BSP在每天同一时间的波动范围在 7.3% 至17.7% (平均11.7% )。24 h 内有一个明显的生物周期性变化,表现为峰值在凌晨4~8 时,然后逐渐下降直到午后14时为最低。其生物周期的最大波幅为±20% ,(平均血浓度为10.5 ng/m l)。结论 血清BSP反映了骨转换的生理变化与年龄有明显相关性,其血清水平24 h 内有一个明显的生物周期,而天与天之间变异性较小。  相似文献   
62.
Mutations of the DNA mismatch repair (MMR) gene hMLH1 have recently been linked to the development of some hereditary and sporadic cancers which frequently display widespread microsatellite instability (MSI). Conflicting results regarding the extent of MSI in myeloid leukaemias prompted us to perform mutational analysis of all 19 exons of the hMLH1 gene by polymerase chain reaction-single-stranded conformation polymorphism (PCR-SSCP) and sequence analysis in a total of 133 patients with acute and chronic myeloid leukaemia. Apart from one exonic and one intronic polymorphism, no mutations were detected in any of the samples indicating that the major MMR gene hMLH1 is not involved in the pathogenesis or progression of myeloid malignancies.  相似文献   
63.

Background  

Although pulsed electromagnetic field (PEMF) stimulation may be clinically beneficial during fracture healing and for a wide range of bone disorders, there is still debate on its working mechanism. Mesenchymal stem cells are likely mediators facilitating the observed clinical effects of PEMF. Here, we performed in vitro experiments to investigate the effect of PEMF stimulation on human bone marrow-derived stromal cell (BMSC) metabolism and, specifically, whether PEMF can stimulate their osteogenic differentiation.  相似文献   
64.
陆金春等[1]所著的"中国118家实验室精液分析状况的调查"一文主要回顾了当前在中国采用的精液分析方法.  相似文献   
65.
AIM:To investigate the 10-year results of treating low rectal cancer by a single surgeon in one institution.METHODS:From Oct 1998 to Feb 2009,we prospectively followed a total of 62 patients with cT2-4 low rectal cancer with lower tumor margins measuring at 3 to 6 cm above the anal verge.All patients received neoadjuvant chemoradiation(CRT) for 6 wk.Among them,85% of the patients received 225 mg/m2/d 5-fluorouracil using a portable infusion pump.The whole pelvis received a total dose of 45 Gy of irradiation in 25 fractions over 5 wk.The interval from CRT completion to surgical intervention was planned to be approximately 6-8 wk.Total mesorectal excision(TME) and routine defunctioning stoma construction were performed by one surgeon.The distal resection margin,circumferential resection margin,tumor regression grade(TRG) and other parameters were recorded.We used TRG to evaluate the tumor response after neoadjuvant CRT.We evaluated anal function outcomes using the Memorial Sloan-Kettering Cancer Center anal function scores after closure of the defunctioning stoma.RESULTS:The median distance from the lower margin of rectal cancer to the anal verge was 5 cm:6 cm in 9 patients,5 cm in 32 patients,4 cm in 10 patients,and 3 cm in 11 patients.Before receiving neoadjuvant CRT,45 patients(72.6%) had a cT3-4 tumor,and 21(33.9%) patients had a cN1-2 lymph node status.After CRT,30 patients(48.4%) had a greater than 50% clinical reduction in tumor size.The final pathology reports revealed that 33 patients(53.2%) had a ypT3-4 tumor and 12(19.4%) patients had ypN1-2 lymph node involvement.All patients completed the entire course of neoadjuvant CRT.Most patients developed only Grade 1-2 toxicities during CRT.Thirteen patients(21%) achieved a pathologic complete response.Few post-operative complications occurred.Nearly 90% of the defunctioning stomas were closed within 6 mo.The local recurrence rate was 3.2%.Pathologic lymph node involvement was the only prognostic factor predicting disease recurrence(36.5% vs 76.5%,P = 0.006).Ne  相似文献   
66.
The ability of 6-ketocholestanol to increase the skin permeation of the prodrug aminolevulinic acid (5-ALA) was investigated. 6-Ketocholestanol was incorporated together with 5-ALA in four different formulations. Preparations used were a liquid solution/suspension of 5-ALA in buffer, 5-ALA in phospholipid liposomal formulations with and without gelating agent, and finally, a complex cream formulation also including phospholipids. Standard diffusion experiments of 5-ALA using Franz-type diffusion cells and porcine skin were performed. Drug stability was monitored by analyzing the 5-ALA content in the different formulations over time and viewing the preparation for microbial contamination. The analysis of 5-ALA as a nonfluorescent probe was performed after chemical reaction, leading to a fluorescent derivative. The 5-ALA permeation through porcine skin was increased threefold by 6-ketocholestanol in the cream formulation. The chemical stability of 5-ALA in the tested formulations was in the range of about 33 to 72% after an observation period of 28 days. After that time point microbial stability was no longer evident for formulations 2 and 3. Formulation 1 could be observed until day 34, and only formulation 4 showed a microbial stability over the whole observation period of 42 days.  相似文献   
67.
68.
目的:观察脊髓损伤后不同时间移植真皮多能干细胞对大鼠运动功能修复的影响。方法:实验于2006-06/2007-03在第三军医大学生理学教研室完成。①实验材料:实验动物2~4月龄SPF级SD大鼠,体质量(210±40)g,雌雄不限,由第三军医大学实验动物中心提供。真皮多能干细胞为第三军医大学防原医学系从SD大鼠真皮中提取和分离。②实验方法:将42只SD大鼠在L4水平制成脊髓全横断损伤模型。将动物随机分为对照组(n=6)、真皮多能干细胞移植组(n=36)。真皮多能干细胞移植组又分为6个时间点:损伤后1,4,7,10,14,21d移植组,每组6只。各移植组于伤处移植大鼠真皮多能干细胞,而对照组于损伤后7d注射等量磷酸盐缓冲液。③实验评估:分别于移植后1d、1周、4周、8周、12周对各组大鼠进行动物行为学和脊髓诱发电位检测。结果:42只实验大鼠均进入结果分析,无脱落。①动物行为学评分:4周以后各组动物行为学评分比较差异有显著性意义(P<0.05),移植组明显高于对照组(P<0.05),各移植组间比较,以损伤后7,10d移植组动物行为学评分改善最显著。②各组大鼠脊髓诱发电位检查:体感诱发电位和运动诱发电位潜伏期和波幅值于移植后8,12周后明显高于对照组(P<0.05),各移植组间比较,以损伤后7,10d移植组体感诱发电位和运动诱发电位潜伏期和波幅值改善最显著。结论:脊髓损伤后7~14d进行真皮多能干细胞移植可明显改善大鼠后肢的运动功能。  相似文献   
69.
李全  沈旭  邵华武  谢毓元 《药学学报》1995,30(6):471-475
Seventeen compounds having the structure of 2,3-diacetoxy-1,4-bis(3′,5′- dioxo-N4′-substituted piperazinyl methyl)benzene were designed and synthesized based on chelation hypothesis. Their antitumor activities on P388 cells,Hep cells and SGC 7901 cells in vitro were tested. Preliminary results showed that compound 4e has potent antitumor effect against P388 cells and.Hep cells in vitro.  相似文献   
70.
The purpose of the present study was to determine the significance of phloretin on the topical permeation of lidocaine using different semisolid preparations as delivery systems. One hydrophilic and three lipophilic formulations were used. After estimation of the solubility of phloretin and lidocaine in the vehicles and analysis of the viscoelastic properties, standard diffusion experiments with Franz type diffusion cells through porcine skin were performed. Results indicate a general lidocaine enhancement by phloretin in the tested vehicles. The permeation was enhanced 1.39-fold in the hydrophilic formulation and between 1.25- and 1.76-fold in the lipophilic formulations.  相似文献   
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