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111.
人Heparanase基因真核和原核表达载体的构建及融合蛋白的表达 总被引:1,自引:1,他引:0
目的:构建人Heparanase基因的真核、原核表达载体,大肠杆菌表达其融合蛋白.方法:采用反转录.聚合酶链反应从人肝癌细胞株HepG2cDNA中,分别扩增出Heparanase编码基因,用限制性内切酶BamHI消化后,插入真核表达载体pcDNA3.1中,经酶切鉴定与测序证实后,连接成包括完整的人Heparanase基因ORF区的真核表达载体,以亚克隆法构建于原核表达载体pRSET的相应酶切位点,转化大肠杆菌BL21菌株,异丙基β-D硫代半乳糖苷(IPTG)诱导产生融合蛋白.结果:构建的人Heparanase基因表达载体经序列测定证实,与GenBank登录结果完全一致;双酶切鉴定证实,克隆基因正确插入载体pcDNA3.1及pRSET;SDS-PAGE证实融合蛋白表达成功.结论:成功构建了人Heparanase基因真核、原核表达载体,成功正确表达了6His/Heparanase融合蛋白 相似文献
112.
C. Faldini S. Pagkrati F. Acri M. T. Miscione D. Francesconi S. Giannini 《Journal of orthopaedics and traumatology》2007,8(3):128-133
Degenerative spondylolisthesis is characterized by the slippage of one vertebral body over the one below, with association
of intervertebral disc degeneration and degenerative arthritis of the facet joints, which cause spinal stenosis. The aim of
this study was to evaluate the clinical and radiographic results of 22 patients with symptomatic degenerative spondylolisthesis,
operated on by decompressive laminectomy and instrumented posterolateral fusion associated with interbody fusion (PLIF). Mean
age at surgery was 64 years (range, 57–72). Clinical results were evaluated on a questionnaire at the last follow-up visit
concerning postoperative low back and leg pain, restriction of daily life activities, and resumption of sports activity. Lumbar
spine radiographs were used to evaluate the status of fixation devices, the reduction of the spondylolisthesis, the lumbar
sagittal balance and the presence of spinal fusion. No intraoperative or postoperative complications were encountered. There
were no superficial or deep infections, fixation device loosening, or hardware removal. Mean follow-up time was 4 years (range,
3–6 years). Clinical outcome was excellent or good in 19 patients and fair in 3 patients. Preoperatively, mean forward vertebral
slipping on neutral lateral radiographs was 5 mm, while postoperatively it decreased to 3 mm. Preoperatively, mean sagittal
motion was 3 mm and angular motion was 8°, while postoperatively these values decreased to 1 mm and 1°, respectively. This
study demonstrated that spinal decompression followed by transpedicular instrumentation associated with PLIF technique is
a valid surgical option for the treatment of degenerative spondylolisthesis with symptomatic spinal stenosis. Clinical outcome,
intended as relief of pain and resumption of activity, was improved significantly and fusion rate was high. 相似文献
113.
[目的]通过与自体髂骨进行比较,评价医用硫酸钙单独应用的成骨能力,并探讨其可能的成骨机理。[方法]建立家兔腰椎后外侧融合模型,以自身作为对照,双侧横突间植骨,左侧植入硫酸钙颗粒,右侧植入自体髂骨。于术后3、6、12周行X线、CT及组织学检查。[结果]术后3周,硫酸钙尚可见残留颗粒,自体骨完全降解;植骨区域内均可见到大量的破骨细胞,并有血管纤维组织长入。术后6周,硫酸钙完全降解,影像学检查两者之间没有明显的差异,表现为局部骨密度增高,新骨成形;组织学检查两侧植骨区内均为大量的透明软骨形成,自体髂骨植骨区内可见散在的骨小梁结构。术后12周,组织学及影像学上二者没有任何的差别,两侧形成的骨组织与家兔的椎体骨组织结构相同。[结论]医用硫酸钙作为骨移植替代材料,除了具有良好的骨传导性外,硫酸钙可能还具有骨诱导性,其成骨能力与自体髂骨相当,医用硫酸钙单独应用可以取得良好的融合效果。 相似文献
114.
退变性症状性腰椎侧凸的手术治疗 总被引:3,自引:1,他引:2
[目的]探讨后路椎管减压、椎弓根螺钉间断固定、椎间植骨融合、矢状位重建术式治疗退变性症状性腰椎侧凸的临床效果。[方法]1999年1月-2006年4月,采用经后路椎管减压、椎弓根螺钉间断固定、椎间植骨融合、矢状位重建术式治疗退变性症状性腰椎侧凸37例,男21例,女16例;年龄51—82岁,平均62.6岁。所有病例拍摄腰椎正侧位片及Bending片,常规备CT和MRI。根据患者下肢症状行全椎板或半椎板减压,神经根扩大,椎间植骨融合及椎弓根螺钉间断固定。[结果]本组病例均获随访(1—6年,平均2年零7个月),术后临床症状均明显缓解,按JOA评分,手术疗效优良率91.9%,侧凸平均矫正率54.8%。随访期间无明显矫正度数及椎间隙高度丢失,术后3个月、1年复查X片内置物无松动及断裂,植骨融合时间平均11.6周。[结论]对于退变性症状性腰椎侧凸患者:(1)采取个体化治疗,年龄不是绝对手术禁忌证,病程长短不是决定手术疗效的重要指标;(2)后路椎管减压、椎弓根螺钉间断固定、椎间植骨融合、矢状位重建术是安全有效的理想术式。 相似文献
115.
116.
感染日本血吸虫的家兔治疗前后肝纤维化动态观察 总被引:1,自引:1,他引:0
感染日本血吸虫的家兔治疗前后肝纤维化B超声像图模型、血清MAO水平及病理学结果表明,血吸虫引起的肝纤维化变化过程与血清MAO水平升降趋势趋向一致,均在18周达到高峰。解剖与病理学检查结果基本相符,血吸虫性肝纤维化形成后,只要及时给予杀虫治疗,肝纤维化部分可发生逆转。 相似文献
117.
A wireless device for the assessment of tardive dyskinesia by means of digital image processing is presented. Four skin-cream dots placed around the subjects' mouth are recorded by a video camera. The image is passed to a framegrabber with a signal processor, where it is converted from analogue to digital. A fast spot-detecting algorithm implemented on the signal processor tracks the dots and passes the information to a personal computer, where a Fourier transformation is performed to calculate the frequency spectrum of the movements. The device provided detailed information on the magnitude and on the frequencies of the movements. Data from a longitudinal investigation suggest a higher sensitivity and reliability than conventional rating scales to detect and evaluate abnormal perioral movements. The device might be useful for the early detection, for the longitudinal assessment (p.e. clinical trials) and in some cases for the differential diagnosis of tardive dyskinesia, thus providing a tool for both research and clinical purposes. 相似文献
118.
R.J. Aitken D.W. Buckingham K. West J. Brindle 《American journal of reproductive immunology (New York, N.Y. : 1989)》1996,35(6):541-551
PROBLEM: To develop a methodology to determine a) the leukocytic contribution to reactive oxygen species generation by human sperm suspensions and b) the therapeutic value of removing these cellular contaminants. METHODS: Leukocytes were removed with paramagnetic beads or colloidal ferrofluids coated with anti-CD45 antibody. The sperm suspensions were monitored for oxidant generation by chemiluminescence, leukocyte contamination by immunocytochemistry, and fertilizing potential using zona-free hamster oocytes. RESULTS: Percoll®-prepared human sperm suspensions exhibited a competence for PMA-induced reactive oxygen species generation which was significantly correlated with leukocyte contamination. However, the purified spermatozoa remaining after paramagnetic bead treatment, also demonstrated an intrinsic capacity for PMA-responsive reactive oxygen species generation and, freed from the oxidative stress created by the leukocytes, exhibited a significantly enhanced capacity for sperm-oocyte fusion. CONCLUSIONS: Although human spermatozoa can generate reactive oxygen species, sperm function is inhibited by the additional oxidative stress created by contaminating leukocytes. Removal of these cells with paramagnetic beads enhances fertilizing potential. 相似文献
119.
Claudine Savy Fatima Moussafi Jacques Durand Jrme Yelnik Axelle Simon Jeanine Nguyen-Legros 《The Journal of comparative neurology》1995,355(3):392-404
The morphology and distribution of dopaminergic interplexiform cells in adult rat and monkey retinas were analyzed to determine any correlation with the function of dopamine in the outer retinal layers. The retinas were processed as whole mounts for tyrosine hydroxylase immunohistochemistry. There was a network formed by the sclerally directed processes of interplexiform cells in the inner nuclear, outer plexiform, and outer nuclear layers running throughout the retina. Their density was higher in the superior retina than in the inferior retina of the rat and was especially high in the superior temporal quadrant. The external network in this quadrant was significantly less dense in the monkey than in the rat, as are the interplexiform cells. The somata of interplexiform and other dopaminergic cells were about the same size in both rats and monkeys. Computer-assisted reconstruction of external arborizations of individual cells showed that external processes lay very close to horizontal and photoreceptor cells and also to blood capillaries. Because they were long, thin, and highly varicose; branched at right angles; and often arose from an axon hillock, the external processes were identified as axons. Therefore, we define the dopaminergic interplexiform cells as multiaxonal neurons, with at least one outwardly directed axon that reaches the outer plexiform layer. The function of the network of external processes from the interplexiform dopaminergic cells is discussed in terms of modulating the release of dopamine to external layers. 相似文献
120.
核医学影像设备的发展与临床应用 总被引:3,自引:3,他引:0
γ相机和SPECT只能进行常规单光子显像,PET和双探头SPECT符合显像系统既能进行单光子显像,又能进行正电子符合显像,PET/CT系统的出现不仅提供高质量的衰减校正图像,保证了正电子显像校正数据的可靠性,而且能进行同机图像融合,提高了影像定位诊断的准确性。本文简要介绍了核医学影像设备发展历程,PET和PET/CT的原理以及在临床的应用。 相似文献