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221.
222.
Yanhong Li Shuanke Wang Yayi Xi Jing Wang Wenjie Pan Yingbin Shi Mige Wang 《中国神经再生研究》2007,2(8):471-474
BACKGROUND: At present, there is still lack of effective drugs for chronic spinal cord injury, whereas it is found recently that estrogen has a neuroprotective effect on brain and spinal cord injuries.
OBJECTIVE: To observe the effect of estrogen on the apoptosis of nerve cells after gradual chronic spinal cord injury in ovariectomized rats.
DESIGN: A randomized controlled animal trial.
SETTING: Institute of Orthopaedics, the Second Hospital of Lanzhou University.
MATERIALS: Sixty-five female Wistar rats of common degree, weighing 220–250 g, were provided by the experimental animal center of Lanzhou University. The rats were randomly divided into sham-operated group (n =5), estrogen-treated group (n =30) and saline control group (n =30), and the latter two groups were observed at 1, 3, 7, 14, 28 and 60 days respectively, and 5 rats for each time point.
METHODS: All the rats were treated with bilateral oophorectomy 2 weeks before the experiment. T10 vertebral lamina was revolved into using plastic screw. The spinal canal impingement was not induced initially. After that, the original incision was opened to expose the screw every 7–10 days.
MAIN OUTCOME MEASURES: The apoptosis and Caspase-3 positive cells in the damaged spinal cord were detected using terminal deoxynucleotidal transferase-mediated dUTP-biotin nick end labeling (TUNEL) method and Caspase-3 immunohistochemical staining at 1, 3, 7, 14, 28 and 60 days after chronic spinal cord injury respectively.
RESULTS: Totally 65 rats were used, and the deleted ones during the experiment were supplemented by others. Changes of Caspase-3 expression after spinal cord injury: In the sham-operated group, only a small amount of Caspase-3 proteins were observed in the rat spinal cord, mainly located in motor neurons of spinal cord anterior horn. In the estrogen-treated group and saline control group, positive cells expressed occasionally at 1 day postoperatively, began to increase obviously at 7 days after injury, strongly expressed at 14 and 28 days, but decreased at 60 days, mainly located in the neurons of spinal cord gray matter anterior horn, and they expressed fewer in the motor neurons and white matter of ventral horn, and there were obvious differences between the estrogen-treated group and saline control group at 7, 14, 28 and 60 days (P < 0.05).
CONCLUSION: Estrogen can reduce the apoptosis of nerve cells and promote the recovery of neurological function following gradual chronic spinal cord injury. 相似文献
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224.
目的:探讨胃癌肝细胞生长因子受体(c-Met)及肝细胞生长因子(HGF)表达与胃癌肝转移间的相关性。方法:晚期胃癌标本59例,其中11例同时有取自左肝外叶的肝转移标本,应用免疫组化方法对上述组织石蜡标本进行检测。结果:59例胃癌中,c-Met阳性率55.8%(33/59),HGF阳性率28.8%(17/59);在29例发生了同时或异时性肝转移的胃癌标本中,c-Met表达率为75.9%(22/29),HGF阳性率为37.9%(11/29),其中c-Met表达率在有和无肝转移组间有显著差异(P<0.05);在11例胃癌肝转移灶中,9例c-Met阳性表达率为81.8%,3例HGF阳性表达率为27.3%。结论:胃癌组织c-Met表达可能与胃癌肝转移行为相关。 相似文献
225.
Matthias Peltz Tian-Teng He Glenn A Adams Robert Y Chao Michael E Jessen Dan M Meyer 《The Journal of heart and lung transplantation》2005,24(7):896-903
BACKGROUND: Lungs harvested for transplantation are stored while inflated with oxygen, which can serve to support oxidative metabolism. However, strategies aimed at increasing graft metabolism during storage have received little attention. In this study, we added pyruvate to the preservation solution Perfadex and measured the effects on oxidative metabolism and reperfusion lung function. METHODS: Rat lungs were stored for 6 and 24 hours in low-potassium dextran solution at 10 degrees C containing either 5 mmol/liter uniformly carbon-13 (U-(13)C) labeled glucose (Perfadex), 32 mmol/liter 3-(13)C pyruvate (pyruvate), or both (combined). Oxidation of exogenous substrates was measured as the incorporation of (13)C into tricarboxylic acid cycle intermediates by magnetic resonance spectroscopy. Additional groups of lungs with each substrate modification were preserved for 6 or 24 hours and then reperfused. RESULTS: Enrichment of tricarboxylic acid cycle intermediates was low in the Perfadex group (9% at 6 hours and 32% at 24 hours of storage, respectively). In contrast, enrichment was significantly increased in both the pyruvate group (50% and 59%, respectively) and combined group (39% and 54%, respectively) compared with the Perfadex group (p<0.01). Graft function was excellent after 6-hour storage in all groups. All lungs stored for 24 hours exhibited inferior lung function, but oxygenation, pulmonary artery pressures, and airway pressures in the combined group were significantly improved compared with the Perfadex group (p<0.05). CONCLUSIONS: Preservation solution substrate composition influences graft metabolism during storage. The addition of pyruvate to Perfadex increases metabolism during storage and improves reperfusion lung function. 相似文献
226.
目的 探讨胶原凝胶包埋软骨细胞接种BCM支架的三维培养对软骨细胞生长及功能的影响.方法 将胶原凝胶包埋的关节软骨细胞接种BCM支架并在体外培养,应用倒置相差显微镜和扫描电镜观察软骨细胞的粘附、生长和增殖情况,培养14d,行苏木精-伊红、甲苯胺蓝染色观察软骨组织形成情况.结果 软骨细胞在支架上粘附、生长和增殖良好,体外培养14d能形成较成熟的软骨组织.结论 胶原凝胶复合BCM支架具有良好的细胞相容性,可作为负载生长因子的载体. 相似文献
227.
踝关节侧副韧带损伤的超声表现 总被引:6,自引:0,他引:6
目的 分析踝关节侧副韧带损伤的超声图像特征并评价其诊断价值。方法 采用7~13MHz线阵探头探查136例临床怀疑踝关节侧副韧带损伤患者,观察胫舟、胫距前、胫跟、距腓前、跟腓、胫距后、距腓后韧带,共计952条韧带,其中,51例的超声结果与手术比较。结果 46例侧副韧带完全及部分撕裂伤的超声诊断与手术结果符合。侧副韧带挫伤以肿胀为主,部分撕裂伤超声表现为韧带局部连续性中断(跟腓韧带)和不规则低-无回声区内见丝状结构相连,完全撕裂伤超声表现为韧带连续性中断,断端挛缩(跟腓韧带)和不规则低-无回声区贯穿整条韧带,无明显断端挛缩征。结论 高频超声对踝关节侧副韧带损伤的诊断无创、较准确、廉价,具有较高的临床应用价值。 相似文献
228.
Study of pathological morphology in chronic sinusitis] 总被引:1,自引:0,他引:1
OBJECTIVE: To study the pathological characteristics and regularity of chronic sinusitis (CS) in different clinical types, tc estimate the reliability and feasibility of CS classification on the pathologic basis. METHODS: HE, Van Gieson's, alcian blue-periodic acid-schiff(AB-PAS) staining was used to observe the changes of epithelium, to measure the thickness of basement membrane and the area of mucous glands. The ultrastructural changes of pseudostratified ciliated columnar epithelium were observed under transmission electron microscope (TEM) and scanning electron microscope (SEM). RESULTS: The epithelial fiber tissue was increased, the basement membrane was thickened, and the mucous glands were obviously increased in CS under the light microscope. Subepithelial fibrosis and thickened basement membrane were most obviously seen in type III of CS and the hyperplasia of mucous glands was most distinct in type II. Under the TEM, abnormal structure of cilia, decrease of ciliated cells, increase of goblet cells were detected in all three CS types. Under the SEM, the cilia of every types showed the ingravescenced process of pathological changes from slight cilium disorder, disorientation, to desquamation of most cilia and replacement of microvilli. CONCLUSION: There is significant distinction of mucous membrane structure among three types. The Chinese classification of CS has pathological basis, it represents the occurrence, development and regularity of CS, and it can be used as basis in further study, communication and evaluation for surgical effect of CS. 相似文献
229.
230.
Garth Bissette Violetta Klimek Jun Pan Craig Stockmeier Gregory Ordway 《Neuropsychopharmacology》2003,28(7):1328-1335
Research evidence that corticotropin-releasing factor (CRF) plays a role in the pathophysiology of major depressive disorder (MDD) has accumulated over the past 20 years. The elevation of lumbar cerebrospinal fluid (CSF) concentrations of CRF decreased responsiveness of pituitary CRF receptors to challenge with synthetic CRF, and increased levels of serum cortisol in MDD subjects support the hypothesis that CRF is chronically hypersecreted in at least the endocrine circuits of the hypothalamic-pituitary-adrenal (HPA) axis and may also involve other CRF brain circuits mediating emotional responses and/or arousal. One such circuit includes the excitatory CRF input to the locus coeruleus (LC), the major source of norepinephrine in the brain. Furthermore, there are now reports of decreased levels of CRF in lumbar CSF from MDD patients after symptom relief from chronic treatment with antidepressant drugs or electroconvulsive therapy. Whether this normalization reflects therapeutic effects on both endocrine- and limbic-associated CRF circuits has not yet been effectively addressed. In this brief report, we describe increased concentrations of CRF-like immunoreactivity in micropunches of post-mortem LC from subjects with MDD symptoms as established by retrospective psychiatric diagnosis compared to nondepressed subjects matched for age and sex. 相似文献