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71.
肝癌介入诊疗中DSA血流动力学参数分析初步探讨 总被引:1,自引:0,他引:1
目的探讨肝癌TACE介入栓塞前肝动脉造影图像上癌灶、癌旁肝组织、背景肝组织之间血流动力学相关参数的差异性。方法本组共34例,男28例,女6例,均为经临床诊断原发性肝癌后第一次行介入诊疗。介入栓塞治疗前均先行肝固有动脉插管造影,采用高压注射器团注对比剂(370mgl/m1)15ml,流率5ml/s,注射后延时0.5s曝光,以4帧/s(fps)帧率持续采集图像15s,获取60(4x15)幅图像。图像处理采用自主开发的图像处理软件DSAanalysis1.0。分别在癌灶的肿瘤染色区、癌旁肝组织及背景肝组织等区域各选定兴趣区(ROI),并生成各区域ROI的时间一密度曲线(TDC),对各TDC进行定量分析,获得与血流动力学相关的参数并对比,相关的参数包括:视频密度增量峰值(AXPV)、达峰时间(TP)、显影持续时间(TD)、TDC升支及降支最大斜率(KmaxU及KmaxD)。结果癌灶、癌旁肝组织、背景肝组织的TD分别为12.97s±0.89、7.75s±0.89、4.99s±0.37;KmaxD分别为36.0s^-1±8.2、90.8s^-1±24.3和142.6S^-1±26.4s。癌灶、癌旁肝组织、背景肝组织的TD及KmaxD两两对比均具有显著性的差异(P〈0.01)。而其他参数三者之间差异无统计学意义(P〉0.05)。结论通过对DSAanalysis1.0软件获得的TDC进行分析,可获得与血流动力学相关参数值,其中TD、KmaxD可在一定程度上反映癌灶、癌旁肝组织及背景肝组织的血流动力学差异。 相似文献
72.
Elastin point mutations cause an obstructive vascular disease, supravalvular aortic stenosis 总被引:7,自引:2,他引:7
Li DY; Toland AE; Boak BB; Atkinson DL; Ensing GJ; Morris CA; Keating MT 《Human molecular genetics》1997,6(7):1021-1028
Supravalvular aortic stenosis (SVAS) is an inherited obstructive vascular
disease that affects the aorta, carotid, coronary and pulmonary arteries.
Previous molecular genetic data have led to the hypothesis that SVAS
results from mutations in the elastin gene, ELN. In these studies, the
disease phenotype was linked to gross DNA rearrangements (35 and 85 kb
deletions and a translocation) in three SVAS families. However, gross
rearrangements of ELN have not been identified in most cases of autosomal
dominant SVAS. To define the spectrum of ELN mutations responsible for this
disorder, we refined the genomic structure of human ELN and used this
information in mutational analyses. ELN point mutations co-segregate with
the disease in four familial cases and are associated with SVAS in three
sporadic cases. Two of the mutations are nonsense, one is a single base
pair deletion and four are splice site mutations. In one sporadic case, the
mutation arose de novo. These data demonstrate that point mutations of ELN
cause autosomal dominant SVAS.
相似文献
73.
Adaptive differentiation of murine lymphocytes. IV. (Responder × Nonresponder) F(1) T cells can be taught to preferentially help nonresponder,rather than responder, B cells
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Responses to the synthetic terpolymer L-glutamic acid, L-lysine, L-tyrosine (GLT) in the mouse are controlled by H-2-1inked Ir-GLTgenes. (Responder × nonresponder) F(1) hybrid mice, themselves phenotypic responders, can be primed with GLT to develop specific helper cells capable of interacting with 2,4-dinitrophenyl hapten (DNP)-primed F(1) B cells in response to DNP-GLT. Unlike the indiscriminant ability of F(1) helper T cells for conventional antigens (i.e. not Ir gene-controlled), which can help B cells of either parental type (as well as F(1)) equally well, GLT-primed F(1) T cells can only provide help under normal circumstances for B lymphocytes of responder parent origin; they are unable to communicate effectively with nonresponder parental B cells (1, and the present studies). The present studies reveal, however, that the induction of a parental cell-induced allogeneic effect during priming of F(1) mice to GLT actually dictates the direction of cooperating preference that will be displayed by such F(1) helper cells for B cells of one parental type or the other. Thus, F(1) T cells, primed to GLT under the influence of an allogeneic effect induced by parental BALB/c cells, develop into effective helpers for nonresponder A/J B cells, but fail to develop effective helpers for responder BALB/c B cells, and vice-versa. In contrast, F(1) T cells, primed to GLT under the influence of an allogeneic effect induced by either parental type, display significantly enhanced levels of helper activity for B cells derived from F(1) donors. These results are interpreted to reflect the existence of two interdependent events provoked by the allogeneic effect: one event augments the differentiation of GLT-specific helper T cells belonging to the subset corresponding to the opposite parental type; this would explain the development of increased helper activity provided to partner B cells of opposite parental type (as well as of F(1) origin). The second event, we postulate, involves the production of responses against the receptors which normally self-recognize native cell interaction determinants; this form of anti-idiotype response is restricted against self- recognizing receptors of the same parental type used for induction of the allogeneic effect, hence explaining diminished helper activity of such F(1) cells for partner B lymphocytes of corresponding parental type. 相似文献
74.
组织工程化人形下颌骨髁状突的实验研究 总被引:4,自引:0,他引:4
目的 评价采用组织工程技术构建人下颌骨髁状突软骨复合组织的可行性。方法 以可降解生物材料聚羟基乙酸 (polyglycolicacid ,PGA) /聚乳酸 (polylacticacid ,PLA)预制人下颌骨髁状突模型 ,体外培养扩增牛骨膜成骨细胞和牛关节表面软骨。实验分 3组 :第 1组 ,模型内仅注入 1.5 %藻酸钙和 30 %氧化乙丙烯 ;第 2组 ,模型内分别注入成骨细胞和软骨细胞悬液 ,浓度为 5× 10 7/ml;第 3组 ,模型内接种成骨细胞藻酸钙悬液 ,同时在模型关节表面涂敷软骨细胞 PluronicF12 7悬液 ,浓度为 5× 10 7/ml。分别植入裸鼠皮下 ,12周后取材 ,作大体和组织学观察。结果 第 1组无骨和软骨形成 ,模型支架明显缩小 ,形态不规则 ;第 2组仅留残缺不全的组织结构 ,标本体积缩小变形 ;第 3组形态结构与原植入模型支架相同 ,组织学观察有骨和软骨组织结构 ,两者界面连接有序 ,骨组织内有大量新生骨板。结论 以人工合成生物材料预制人下颌骨髁状突支架 ,采用组织工程技术 ,可以在裸鼠体内构建具有骨软骨复合结构的正常形态的人形下颌骨髁状突 ,从而为进一步临床应用提供了理论依据 相似文献
75.
76.
郭永建 《福建医科大学学报》1994,(1)
采用间接ELISA检测23名肾移植受者血清巨细胞病毒(CMV)抗体,共检出18名(78%)活动性CMV感染,其中10名(44%)为原发性感染。结果证实CMV-IgE和-IgA具有较好的血清学诊断价值,优于CMV-IgM。 相似文献
77.
目的 研究血管内皮生长因子(VEGF)对缺血/再灌注损伤胰腺组织细胞凋亡的影响.方法 将雄性sD大鼠30只随机分为3组(n=10),A组为假手术组,B组为缺血/再灌注损伤组,C组为缺血/再灌注损伤+VEGF反义寡核苷酸组.通过血管夹阻断大鼠腹腔干及肠系膜上动脉30 min,然后去除血管夹再灌注6 h,建立大鼠胰腺缺血/再灌注损伤模型.对各组胰腺组织进行VEGF免疫组化染色及TUNEL法细胞凋亡检测.结果 缺血/再灌注损伤后胰腺组织出现细胞凋亡,同时VEGF蛋白表达上调.缺血/再灌注损伤+VEGF反义寡核苷酸组的胰腺组织VEGF蛋白表达较缺血/再灌注损伤组显著减少(P<0.05),前者细胞凋亡指数较后者明显升高(P<0.05).结论 VEGF能抑制缺血/再灌注损伤胰腺细胞凋亡,可能对胰腺缺血再灌注损伤具有保护作用. 相似文献
78.
Zhongjie Li Shengjie Lai Honglong Zhang Liping Wang Dinglun Zhou Jizeng Liu Yajia Lan Jiaqi Ma Hongjie Yu David L Buckeridge Chakrarat Pittayawonganan Archie CA Clements Wenbiao Hu Weizhong Yang 《Bulletin of the World Health Organization》2014,92(9):656-663
Objective
To evaluate the performance of China’s infectious disease automated alert and response system in the detection of outbreaks of hand, foot and mouth (HFM) disease.Methods
We estimated size, duration and delay in reporting HFM disease outbreaks from cases notified between 1 May 2008 and 30 April 2010 and between 1 May 2010 and 30 April 2012, before and after automatic alert and response included HFM disease. Sensitivity, specificity and timeliness of detection of aberrations in the incidence of HFM disease outbreaks were estimated by comparing automated detections to observations of public health staff.Findings
The alert and response system recorded 106 005 aberrations in the incidence of HFM disease between 1 May 2010 and 30 April 2012 – a mean of 5.6 aberrations per 100 days in each county that reported HFM disease. The response system had a sensitivity of 92.7% and a specificity of 95.0%. The mean delay between the reporting of the first case of an outbreak and detection of that outbreak by the response system was 2.1 days. Between the first and second study periods, the mean size of an HFM disease outbreak decreased from 19.4 to 15.8 cases and the mean interval between the onset and initial reporting of such an outbreak to the public health emergency reporting system decreased from 10.0 to 9.1 days.Conclusion
The automated alert and response system shows good sensitivity in the detection of HFM disease outbreaks and appears to be relatively rapid. Continued use of this system should allow more effective prevention and limitation of such outbreaks in China. 相似文献79.
[目的]探讨早期康复对脑卒中患者日常生活能力的影响。[方法]将符合纳入标准患者按入院时间先后分为康复组和对照组。每组按方案进行治疗,治疗前及治疗40d后分别进行改良巴氏指数评定表评分,根据评分判断临床疗效。[结果]治疗前,康复组患者Barthel指数评分为28.75±13.55,对照组为29.33±14.07,差异无统计学意义(P﹥0.05)。治疗40d后,康复组患者Barthel指数评分为69.50±16.67,对照组为52.33±19.08,两组均有不同程度的改善,但康复组的改善程度明显优于对照组(P﹤0.05)。[结论]早期康复可以明显提高脑卒中患者日常生活能力。 相似文献
80.