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51.
成人成骨细胞与珊瑚羟基磷灰石的体外生物相容性   总被引:13,自引:2,他引:11  
目的:研究成人骨髓成骨细胞与珊瑚羟基磷灰石(carolline hydroxyapatite,CHA)在体外培养条件下的生物相容性。方法:抽取健康成人骨髓组织,置于含体积分数为10%胎牛血清的DMEM培养基中培养,传代后改用含地塞米松、β-甘油磷酸钠和维生素C的条件培养基培养,分为CHA复合细胞组和单纯细胞组,不同时间用倒置相关显微镜,HE染色光镜及扫描电镜观察,MTT法进行细胞增殖测定,并进行细胞微量蛋白含量和碱性磷酸酶的定量检测,结果:成人骨髓成骨细胞体外培养时复合或不复合CHA均生长良好,表现出典型成骨细胞的形态特征和生物学特性,CHA利于细胞的贴附,生长与增殖,并对细胞的功能无不良影响,结论:CHA是较理想的骨组织工程支架材料,成骨细胞复合CHA用于骨缺损的修复,具有广阔的临床应用前景。  相似文献   
52.
保留肾单位手术治疗早期小肾癌21例临床分析   总被引:1,自引:0,他引:1  
OBJECTIVE: To evaluate the clinical effects of nephron-sparing surgery in patients with early-stage small renal cell carcinoma. METHODS: Nephron-sparing surgery was performed in 21 patients with renal cell carcinoma including 1 with solitary kidney, 3 with unilateral tumor and contralateral renal compromise, and 17 with unilateral tumor and normal contralateral kidney. The diameter of the tumors ranged from 1.5 to 6.0 cm, with a mean of 2.8 cm. The tumor diameter in 17 patients with normal contralateral kidney was less than 4 cm (mean 2.5 cm) and the average diameter in 4 patients with contralateral renal compromise was 4.2 cm. Sixteen cases were in stage T(1), 4 in stage T(2), and 1 in stage T(3). Of the 21 patients, 4 underwent tumor enucleation, 10 polar nephrectomy and 7 wedge resection. RESULTS: All patients were followed up for an average of 40.8 months (7 to 66 months). One patient suffered a right lung and mediastinum metastasis 3 years after the surgery later and 1 with chronic glomerulonephritis required dialysis 27 months after the operation. No surgical complication or local recurrence were found in other patients. CONCLUSION: As a safe and effective therapy for early-stage small renal cell carcinoma, nephron-sparing surgery can be considered as the gold-standard therapy for patients with lesions less than 4 cm in T(1) and T(2) stages of localized unilateral tumor with normal contralateral kidney.  相似文献   
53.
赤芍总苷对沙土鼠全脑缺血再灌注损伤的保护作用   总被引:3,自引:0,他引:3  
OBJECTIVE: To study the protective effects of the total paeony glycoside (TPG) against global cerebral ischemia-reperfusion injury in gerbils. METHODS: Gerbils models of global cerebral ischemia-reperfusion injury were prepared by bilateral common carotid artery ligation for 12 min followed by 24-hour reperfusion. The effects of TGP on brain edema index, superoxide dismatase (SOD) activity and malonaldehyde (MDA) concentration of the cerebral tissue homogenate and pathology of the brain were examined 24 h after model establishment. RESULTS: Compared with the model group, TPG at the doses of 200 and 400 mg/kg could significantly relieve brain edema, enhance SOD activity and lower MDA concentration in the gerbils. Pathological examination showed that the gerbils with TPG treatment had milder injury of the cells in the hippocampal CA1 region. CONCLUSIONS: TPG has obvious protective effects against global cerebral ischemia-reperfusion injury.  相似文献   
54.
目的总结和探讨脑血管造影和载瘤动脉闭塞在治疗颅内巨大动脉瘤上的作用及特点。方法60例颅内巨大动脉瘤患者,根据其脑血管造影的特点采取血管内介入方法[可脱式球囊和(或)弹簧圈]闭塞载瘤动脉近端53例、闭塞载瘤动脉两端后孤立动脉瘤7例;其中23例闭塞前先行颅内-外血管搭桥术。结果出院时Rankin评分分级:单纯血管内介入治疗组37例中轻残3例,合并颅内-外血管搭桥术组23例中死亡1例、重残2例。1-6年的影像学随访动脉瘤无复发。结论血管内介入结合颅内-外血管搭桥术闭塞载瘤动脉是治疗颅内巨大动脉瘤的方法之一。  相似文献   
55.
Wall-eyed bilateral internuclear ophthalmoplegia (WEBINO) is a rarely reported syndrome. There is dispute about whether WEBINO is caused by a pontine or a midbrain lesion and whether the medial rectus subnuclei are implicated. In a study of the clinical and imaging features of four patients with WEBINO, we found that that three of four lesions involved the midbrain but not necessarily the medial rectus subnuclei.  相似文献   
56.
糖尿病患者腹部手术后消化道功能的观察   总被引:6,自引:0,他引:6  
目的了解糖尿病患者腹部手术后消化道功能恢复情况,为临床进行有针对性的护理提供依据.方法对72例糖尿病患者腹部手术后消化道功能恢复情况进行观察,并随机抽取70例非糖尿病腹部手术患者作对照.结果在肠鸣音恢复及肛门排气时间、进流质饮食后食欲状况、恶心呕吐、腹胀发生情况5个方面进行比较,两组消化道功能恢复差异明显(P均<0.01).结论糖尿病患者腹部手术后消化道功能恢复延迟,临床护理中应予重视.  相似文献   
57.
OBJECTIVES: To explore the morphological and functional findings of transvaginal sonography (TVS) in the diagnosis and management of distal ureteral calculi. METHODS: We retrospectively reviewed the imaging studies in seven cases of distal ureteral calculi (study group) and 20 cases of female volunteers without urinary tract infection (control group). All 27 patients had undergone TVS for assessment of the lower urinary tract. The variables measured on ultrasound included the presence or absence of distal ureteral calculi, the size and location of a calculus if present, the presence or absence of the ureter jet phenomenon, morphological changes of the ureteral papilla and adjoining tissue, and the height of the ureteral papilla, as well as vascular changes seen on Doppler imaging. RESULTS: In the controls, 80% of the ureteral papillae were triangular and 20% trapezoidal. The average (+/-SD) height of the ureteral papillae was 3.5 +/- 0.7 mm on the right and 3.6 +/- 0.9 mm on the left. There was no statistically significant difference between the heights of the right and left papillae (P = 0.619). In the study group, echogenic stones were identified in all seven patients and a hypoechogenic tubular structure connected to the involved papilla was identified in 6/7 patients. The average height of the involved papilla was 6.7 +/- 1.6 mm. Ureteric jets were visible in all patients in both the study and control groups. CONCLUSION: In patients with distal ureteral calculi, TVS provides a rapid, non-invasive and repeatable means of assessing the morphology and function of the distal ureter.  相似文献   
58.
通过深入分析我国中医药科学性研究中所存在的问题,依据协同学理论,提出了中医药科学性的理论基础是协同学的观点。基于此,阐释了中医药科学性的协同学解释,这在一定意义上为中医药科学性的研究提供了新的视角和有益的启示。  相似文献   
59.
Serine hydroxymethyltransferase (SHMT) provides activated one-carbon units required for the biosynthesis of nucleotides, protein, and methyl group by converting serine and tetrahydrofolate to glycine and N(5),N(10)-methylenetetrahydrofolate. It is postulated that SHMT activity is associated with the development of methotrexate resistance and the in vivo activity of SHMT is regulated by the binding of N(5)-CHO-THF, the rescue agent in high-dose methotrexate chemotherapy. The aim of this study is to advance our understanding of the folate-mediated one-carbon metabolism in zebrafish by characterizing zebrafish mitochondrial SHMT. The cDNA encoding zebrafish mitochondrial SHMT was cloned, overexpressed in Escherichia coli, and purified with a three-step purification protocol. Similarities in structural, physical, and kinetic properties were revealed between the recombinant zebrafish mitochondrial SHMT and its mammalian orthologs. Surprisingly, leucovorin significantly inhibits the aldol cleavage of serine catalyzed by zebrafish cytosolic SHMT but inhibits to a lesser extent the reaction catalyzed by the mitochondrial isozyme. This is, to our knowledge, the first report on zebrafish mitochondrial folate enzyme as well as the differential inhibition of leucovorin on these two SHMT isoforms. Western blot analysis revealed tissue-specific distribution with the highest enrichment present in liver for both cytosolic and mitochondrial SHMTs. Intracellular localization was confirmed by confocal microscopy for both mitochondrial and cytosolic SHMTs. Unexpectedly, the cytosolic isoform was observed in both nucleus and cytosol. Together with the previous report on zebrafish cytosolic SHMT, we suggest that zSHMTs can be used in in vitro assays for folate-related investigation and antifolate drug discovery.  相似文献   
60.
目的:探讨腰椎形态结构变化对峡部裂性滑脱及小关节退变的作用和意义。方法:采用改良的“非种子区域分割方法”及非平行“最佳切割平面”等一系列新型计算机辅助设计(CAD)方法精确建立包括椎间盘高度、腰椎小关节角、椎间盘前凸角改变的L4~L5活动节段有限元模型;在2700N轴向压缩载荷条件下,分别对各有限元模型的峡部、小关节应力、小关节接触力以及椎间盘负载进行测试。结果:压缩载荷下,腰椎活动节段峡部、小关节等效应力及小关节接触力随椎间盘高度的减小而减小,随小关节角的增大而增加,随椎间盘前凸角的增加而减小。结论:椎间盘高度、腰椎小关节角、椎间盘前凸角等形态结构变化对腰椎节段有限元模型的峡部、小关节应力及小关节接触力有明显的影响。提示腰椎峡部应力性骨折及小关节退变的发生与椎间盘高度、腰椎小关节角、椎间盘前凸角等解剖形态因素有关。  相似文献   
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