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101.
Objective To predict the HLA class Ⅰ restricted cytotoxic T lymphocyte epitopes for human proliferating cell nuclear antigen (PCNA). Methods By using 3 epitope prediction databases which including MHC binder ( BIMAS and SYFPEITHI databases) and proteasome cutting site ( PAProC databases), the epitopes of PCNA were predicted by analyzing several parameters and methods. Results After comprehensive analysis,we have obtained two possible HLA-A0201 restricted CTL epitopes SMSAD-VPLV (228-236, score 447 633. 595 ) and LINEACWDI ( 22-28, score 127 966.779);two HLA-A24 re-stricted CTL epitopos DYEMKLMDL ( 113-121, score 563 994.9 ) and EFARICRDL ( 143-151, score 40 540.7);two HLA-A1101 restricted CTL epitopes LTSMSKILK (72-80, score 1334. 2680 ) and DVPLV-VEYK (232-240,score 736.9236). Conclusion The multi-parameter epitope prediction method is feasi-ble for cytotoxic T lymphocyte epitope prediction.  相似文献   
102.
BACKGROUND: As a non-invasive technique which can provide comprehensive biological information, 1H-magnetic resonance spectroscopy (1H-MRS) may provide valuable reference data for irreversible recovery or reversible changes in ischemic tissue after stroke. OBJECTIVE: To monitor and evaluate the effect of the urokinase thrombolytic therapy after experimental acute cerebral ischemia by 1H-MRS technology and investigate its adaptability. DESIGN: Randomly controlled animal study. SETTINGS: Shenzhen Hospital of Peking University and National Key Laboratory of Pattern and Atom & Molecular Physics, Wuhan Physics and Mathematics Institute, Chinese Academy of Science. MATERIALS: Eleven healthy adult Sprague-Dawley (SD) rats, weighing 260–300 g and of both genders, were supplied by Experimental Animal Center of Tongji Medical Collage, Huazhong University of Science and Technology [SCXK (e) 2004-007]. 4.7T superconducting nuclear magnetic resonance meter was provided by Brucker Company. METHODS: The experiment was carried out in Shenzhen Hospital of Peking University and National Key Laboratory of Pattern and Atom & Molecular Physics, Wuhan Physics and Mathematics Institute, Chinese Academy of Science from August 2003 to December 2005. ① The rats were randomly divided into 30-minute self-thrombo-embolism group (n =6) and 60-minute self-thrombo-embolism group (n =5). Six rats in 30-minute self-thrombo-embolism group were occluded with clot embolus for 30 minutes and 5 rats in 60-minute self-thrombo-embolism group were occluded for 60 minutes. 10 000 U/kg urokinase was dissolved in 2 mL saline and the operation lasted for 5 minutes. ② 1H-MRS was performed before thrombolysis and at 3 hours and 24 hours after successful embolization. The metabolic changes of N-acetyl-L-aspartic acid (NAA)/phosphocreatine (PCr) + creatine (Cr), choline phosphate (Cho)/PCr+Cr and lactic acid (Lac)/PCr+Cr in the region of interests were analyzed. ③ The T2W image was conducted 24 hours after the thrombolytic therapy with TR=500 ms and TE=25 ms. ④ The subjects were sacrificed immediately after 1H-MRS and the brain tissues were cut into pieces and stained with HE method; in addition, pathological changes were observed under optic microscope. MAIN OUTCOME MEASURES: ① Metabolic changes of NAA/PCr+Cr, Cho/PCr+Cr and Lac/PCr+Cr in the region of interests; ② T2W image at 24 hours after the thrombolysis; ③ pathological observation of brain tissue. RESULTS: Eleven rats were all involved in the final analysis. ① Metabolic changes in the region of interests : In 30-minute self-thrombo-embolism group, the Lac peak emerged immediately after the embolism, but the ischemic zone decreased 3 hours after the thrombolytic therapy (0.252±0.01, 0.603±0.01, P < 0.01). Lac/(PCr+Cr) ratio was 0.290±0.01 at 24 hours after thrombolysis, which was higher than that at 3 hours after thrombolysis (P < 0.01). The NAA/ (PCr+Cr) ratio decreased significantly at 3 hours after the thrombolysis as compared with that before thrombolysis (0.922±0.16, 1.196±0.01, P < 0.05). In 60-minute self-thrombo-embolism group, the Lac/(PCr+Cr) ratio was higher at 3 hours after thrombolysis than that before thrombolysis (0.846±0.12, 0.601±0.11, P < 0.05) and the NAA/(PCr+Cr) decreased at 3 hours after the embolism. Fluctuation of NAA/ (PCr+Cr) ranged from 0.68 to 0.75 before thrombolysis and from 0.71 to 0.75 at 3 hours after thrombolysis. ② T2W image: T2W image showed that 2 subjects in 30-minute self-thrombo-embolism group whose Lac/NAA was higher than 0.7 suffered from intracranial hemorrhage. This meant that the subjects with Lac/NAA > 0.7 were more likely to suffer from intracranial hemorrhage. ③ Histological and morphological examinations: Optic microscope demonstrated that interspace surrounding nerve cells was widened at ischemic center; neurons were swelling; nucleus was stained lightly; pyknosis and mesenchymal edema were mainly observed in lateral cortex of brow and vertex and in lateral part of corpus striatum. CONCLUSION: ①Compound parameters in ischemic area before thrombolysis should be regarded as an important predicting marker for thrombolytic therapy, effect evaluation and termination. ② 1H-MRS combining with other imaging technique is a detecting way for screening cases who are suitable for thrombolytic therapy.  相似文献   
103.
104.
Intramedullary epidermoid cysts of the spinal cord are rare tumors, especially those not associated with spinal dysraphism. About 50 cases have been reported in the literature. Of these, only seven cases have had magnetic resonance imaging (MRI) studies. We report two cases of spinal intramedullary epidermoid cysts with MR imaging. Both were not associated with spina bifida. In one patient, the tumor was located at D4 vertebral level; while in the other, within the conus medullaris. The clinical features, MRI characteristics and surgical treatment of intramedullary epidermoid cyst are presented with relevant review of the literature.  相似文献   
105.
目的:探讨眼眶病变的MRI诊断与鉴别诊断价值。方法:对29例经临床病理确诊的眼眶病变的病例进行回顾性分析,重点观察该类疾病的MRI表现。结果:眼眶病变29例,包括肿瘤10例。炎症10例,血管性病变3例,眼肌病变6例。其在MRI表现各具有影像学特征,眼眶肿瘤多表现为位于眼眶内、外的局限性软组织肿块,MR T1WI呈等或稍低信号,T2WI呈高或等信号多见;炎性假瘤则表现为眶内局限性软组织肿块或弥漫性异常信号.MR T1WI呈低信号,T2WI呈高信号,常伴有眼肌肥大或眼环增厚,泪腺肿大等。结论:MRI检查能显示眼眶病变的影像学特征,对其诊断及鉴别诊断具有重要价值。  相似文献   
106.
目的研究高原地区,脱髓鞘疾病与中老年人疾病等因素的关系。方法对我院所有接受过磁共振头部扫描的病人进行评估,确诊出40位脱髓鞘疾病患者,并对大脑7个部位的脱髓鞘疾病按严重性分4级打分,统计临床数据,最后运用统计学方法分析其相关性。结果在40例患者中,出现在大脑半球、放射冠、半卵圆中心和脑室前后角的脑白质损伤频率最多,分别占总量的50%、67.5%、77.5%和87.5%。脑白质损伤患者的平均年龄为47.1岁,这比世界其他地区都有明显的提前。男性患者将近是女性患者的3倍(29∶11)。年龄、慢性高原红细胞增多症、收缩压、脑梗塞与脑白质损伤正相关(P<0.05)。结论对于高海拔地区,有效控制高原心血管疾病的发生对于减少颅脑脱髓鞘疾病的发生具有重要意义。  相似文献   
107.
BACKGROUND: Facial emotions are central to human interaction. Identifying pathophysiology in affect processing circuitry that supports the ability to assess facial emotions might facilitate understanding of affect regulation in pediatric bipolar disorder. METHODS: Ten euthymic, unmedicated pediatric bipolar patients and 10 healthy control subjects matched for age, gender, race, socioeconomic status, and IQ were scanned with functional magnetic resonance imaging. Angry, happy, and neutral faces were presented in 30-sec blocks, with a 20-sec rest period between blocks. Subjects were asked to press a button when each face appeared, to ensure that attention was maintained on-task. RESULTS: In bipolar patients, in response to both angry and happy faces relative to neutral faces, we observed reduced activation of right rostral ventrolateral prefrontal cortex together with increased activity in right pregenual anterior cingulate, amygdala, and paralimbic cortex. Bipolar patients also showed reduced activation of visual areas in occipital cortex together with greater activation in higher-order visual perceptual areas, including superior temporal sulcus and fusiform gyrus with angry faces and posterior parietal cortex with happy faces. CONCLUSIONS: Findings document a disturbance in affective neurocircuitry in pediatric bipolar disorder. Reduced activation in ventrolateral prefrontal cortex might reflect diminished top-down control that leads to the observed exaggerated activation in amygdala and paralimbic areas. Changes in occipital areas might represent an effort to gate sensory input when affective responses to the faces could not be successfully modulated. Disturbances in affect processing circuitry could contribute to emotional dysregulation and social cognitive difficulties in bipolar youth.  相似文献   
108.
p53,p16,PCNA蛋白在食管癌中的表达及其临床意义   总被引:3,自引:0,他引:3  
目的探讨p53,p16,PCNA蛋白在食管癌中的表达及临床意义。方法用免疫组织化学染色SP法对62例食管癌标本进行p53,p16,PCNA蛋白测定。结果62例食管癌中,p53,PCNA蛋白阳性表达均为71.0%(44/62),p16缺失率48.4%(30/62)。p16缺失与肿瘤浸润深度、淋巴结转移密切相关(P<0.05、P<0.01)。而p53,PCNA蛋白同时表达56.5%(35/62),亦与肿瘤浸润深度、淋巴结转移密切相关(P<0.05、P<0.01)。结论食管癌p53,PCNA蛋白同时表达及p16缺失可视为危险预后因素。  相似文献   
109.
目的 研究丙泊酚对大鼠肢体缺血再灌注损伤后肾组织中肿瘤坏死因子-α(tumornecrosisfactor-α,TNF-α)、核因子-κB(nuclear factor-κxB,NF-κB)表达的影响。方法 24只SD雄性大鼠,随机分为假手术对照组(A组),肢体缺血再灌注组(B组)和丙泊酚干预组(C组),每组8只。采用免疫组织化学方法检测TNF-α、NF-κB的表达,行图像分析半定量。结果 B组大鼠肾组织中TNF-α、NF-κB的表达明显高于A组(P〈0.05),C组明显低于B组(P〈0.05)。结论 肢体缺血再灌注后有明显肾损伤,丙泊酚对肢体缺血再灌注肾损伤有一定程度的保护作用,其机制可能与下调大鼠肢体缺血再灌注损伤肾组织中TNF-α、NF-κB的过度表达有关。  相似文献   
110.
目的观察稀土永磁夹板对家兔骨折愈合质量及骨形态发生蛋白(BMP-2)、血管内皮细胞生长因子(VEGF)表达情况的影响,从分子生物学水平探讨磁场促进骨折愈合的作用机制。方法健康成年家兔50只,建立双前肢桡骨中段骨折模型。左侧用稀土永磁夹板固定,作为实验侧;右侧用内镶铅片小夹板固定,作为对照侧。分别于术后1、2、3、4、6周摄双前肢X线片后取材,进行HE及BMP-2、VEGF免疫组化染色并在光镜下观察。结果X线片图像定量分析结果比较,实验侧愈合明显快于对照侧。两侧差异有显著性(P〈0.05)。实验侧在1、2、3、4周VEGF的表达均比对照侧强,两侧差异有显著性(P〈0.05)。实验侧在2、3、4周BMP-2的表达均比对照侧强,两侧差异有显著性(P〈0.01)。结论静磁场在骨折愈合过程中可加强BMP-2、VEGF的表达。自制稀土永磁夹板对实验性骨折愈合有明显的促进作用。  相似文献   
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