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1.
目的评价多排螺旋CT扫描对胃癌的诊断价值。方法对62例胃癌病例行气体对比薄层动态增强CT扫描三维重建技术,层厚0.5mm,在此基础上进行CT仿真胃镜和VRT技术,对获取的图像进行分析。全部病例均经手术和病理证实。结果检出痛变位于胃窦部31例(50%).胃底贲门部10例(16%),体部9例(15.7%),弥漫型12例(19.3%),病变检出率为100%。多薄层动态增强cT扫描三维重建技术表现为局限性胃壁增厚50例,广泛性胃壁增厚12例;其中早期胃癌10例,进展期胃癌52倒;局部和远处淋巴结转移24例;远处转移17例;本组CT定性诊断准确率为96%。结论薄层动态增强CT扫描三维重建技术能清晰显示胃壁及腔内、外病变,并直观反映胃癌大体形态及肿瘤的范围,在胃癌的定位、定性和定量诊断中发挥其独特的优势,是一种最具潜力的检查方法。  相似文献   

2.
目的探讨甲状腺肿块的CT诊断价值。方法回顾分析18例甲状腺肿块的CT特征,并与手术病理对照。结果CT诊断18例甲状腺肿块与手术病理符合率的情况:(1)结节性甲状腺肿7例,诊断符合率71%(5/7);(2)甲状腺腺瘤8例,诊断符合率63%(5/8);(3)甲状腺癌3例,诊断符合率67%(2/3)。结论CT对甲状腺肿块的诊断虽然有很大价值,但是部分甲状腺肿块CT表现无特征性,定位诊断准确,定性诊断困难。  相似文献   

3.
目的评价64层螺旋CT血管成像对脑血管病的诊断及临床应用价值。方法64层螺旋CT血管成像检查确诊脑血管疾病患者60例,50例在1周内行DSA检查。采用减影方法进行后处理,分别得到VR,MIP,TSMIP图像,利用这三种方法重建图像综合评价脑血管病变。结果①脑动脉狭窄或闭塞者46例,其中36例有DSA对照,98.8%的狭窄或闭塞的脑血管与DSA诊断一致,CT血管成像的敏感性,特异性,准确性分别为100%、98.5%、98.8%;②烟雾病3例,均有DSA对照,表现为单侧或双侧大脑中动脉重度狭窄,远端分支异常增多;③脑动脉瘤患者12例,均有DSA对照,后交通动脉瘤7例,前交通动脉瘤3例,大脑中动脉瘤1例,大脑后动脉瘤1例,CT血管成像与DSA显示一致。结论64层螺旋CT层血管成像能快速,准确地诊断各种脑血管疾病,结合减影处理方法提高了诊断的效率和准确性,为临床提供了全面的信息,可作为脑血管疾病患者的首选诊断方法。  相似文献   

4.
英国研究人员在最新一期《柳叶刀》杂志上发表研究报告称,医院常用来诊断疾病的X射线扫描可能是导致一部分人罹患癌症的原因。他们建议医生在使用该诊断方法时权衡利弊。医用X射线检查和计算机断层扫描(CT)是目前普遍用于癌症早期和骨裂诊断的两种方法,也是人们可能接触到的最大的人造辐射源。其辐射能够穿透细胞,破坏DNA ,甚至诱发人体内出现某些癌细胞。牛津大学和英国癌症研究中心的科学家在对15个国家的统计数据进行分析后发现,英国每年诊断出的癌症病例中有0 6 %是由X射线检查所致。在X射线和CT检查更为普遍的日本,每年新增癌症…  相似文献   

5.
目的 探讨急性胰腺炎的CT平扫特征及其诊断价值.方法 对临床明确诊断的30例急性胰腺炎CT表现进行分析评价.结果 30例中CT诊断为急性单纯性水肿性胰腺炎13例,表现为胰腺弥漫性或局限性增大,密度轻度减低,轮廓模糊,以及胰周积液;急性出血坏死性胰腺炎17例,表现为胰腺明显增大,密度弥漫性减低,坏死区密度更低,出血区密度高于正常组织,明显的胰周脂肪坏死和积液.结论 螺旋CT平扫是急性胰腺炎简便有效的影像检查方法.  相似文献   

6.
泌尿系统肿瘤异质性高,易复发和转移。小动物活体成像技术是生物及医学研究领域的一项新兴技术,近年来,其在肿瘤发生发展机制的基础研究中不断深入,这些研究对患者临床诊断、肿瘤转移、预后的判断、抗肿瘤药物研发以及个体化治疗指导具有深远意义。本文纵览近年来相关文献,总结了小动物活体成像技术及其在泌尿系统肿瘤动物模型研究中的应用进展,以期对泌尿系肿瘤的临床诊断、治疗、疗效判断及抗肿瘤药物研发提供新思路。  相似文献   

7.
随着分子生物学的进步,遗传病分子诊断在许多方面取得了显著进展,策略上的改善使我们有可能在分子水平上对多基因遗传病进行诊断;着床前诊断使有遗传病风险的夫妇有望获得完全正常的孩子;RNA诊断适用于检测基因表达的缺陷;着色FISH使染色体病的诊断更加准确可靠。得益于人基因组计划的成果,遗传病分子诊断将进入一个全新的时代。  相似文献   

8.
基因转移的研究进展   总被引:5,自引:3,他引:2  
本文从新的思路上介绍了基因转移的研究进展,首先论述了有性杂交与基因交流和物种进化的关系,重点论述了非有性杂交条件下生物体间、生物体内的基因水平转移研究概况,并讨论了基因转移与生物进化,突变和生物工程的关系及存在的有关问题。  相似文献   

9.
磁盘表层润滑剂在磁头与磁盘之间转移会影响磁头飞行的稳定性.本文采用改进后的粗粒珠簧模型,运用分子动力学方法,研究了磁盘上类金刚石薄膜(diamondlikecarbon,DLC)层粗糙度和磁盘表面凸起对润滑剂在磁盘表面分布及磁头/磁盘之间润滑剂转移的影响.研究结果表明,DLC层粗糙度对润滑膜平均厚度及磁盘表层粗糙度的影响很小;磁盘表面凸起对磁盘表层润滑剂分布的影响明显.类金刚石薄膜层的粗糙度和磁盘表层凸起均可增加转移到磁头上的润滑剂的体积.但磁盘表层粗糙度对磁头/磁盘之间润滑剂转移量的影响明显低于由磁盘表层凸起导致的磁头/磁盘之间润滑剂的转移量.  相似文献   

10.
利用CT进行三维重建需要高达几十亿字节的数据,处理这样的海量数据对PC机或普通图形工作站的CPU来说都将是十分耗时的,重建速度仍是制约三维锥束CT应用的主要因素之一.图形处理器(Graphics Processing unit,GPU)由于其所具有的超长流水线和高度并行化,不仅在图形处理领域得到广泛应用,而且被用来进行通用计算任务.由于计算机图形学中的投影过程和CT的数据生成本质是一致的,基于GPU进行CT重建是提高速度的有效途径,本文首先针对GPU的特点进行概述,之后着重介绍了在GPU上实现CT重建的原理和方法,同时分析了GPU能够实现加速的原因.  相似文献   

11.
Ovariectomy in 3 month-old Rats is followed by a fall in plasma CT level and a decreased secretion of CT after a calcium load. These results show that ovarian hormones may play a role in the direct or indirect control of the secretion of CT in the adult female.  相似文献   

12.
Summary S8CT injected at the time of immunization significantly enhances specific IgM-production but has no effect on IgG-formation. Mitogen (PHA-P) induced macrophage migration inhibition of cells of S8CT pretreated animals is reduced. The same effect is observed, when normal cells are tested in the presence of S8CT in vitro. Blast transformation of B-lymphocytes but not of thymocytes is significantly stimulated by S8CT. Acid phosphatase activity is also stimulated in B-cells and- to a lesser degree-in cortisone-resistant T-lymphocytes whereas the activity of the total thymocyte population is reduced. No effect was seen on phagocytosis and intracellular bactericidal activity. A stimulatory effect of S8CT for B-cells is postulated.Presented in part at the Xth International Congress of Allergology and Clinical Immunology, Jerusalem/Israel 1979, Nov. 4–11.  相似文献   

13.
Summary According to the writer's theory a great number of different desoxyribonucleic and ribonucleic acids exist in each cell: desoxyribonucleic acids in the nucleus (genes) and ribonucleic acids in the cytoplasm (microsomes). Through catalytic actions the macromolecular desoxyribonucleic acids govern the building of macromolecular ribonucleic acids, and, in turn, these control the production of cytoplasmic enzymes. In truth, the enzymic equipment results simultaneously from the effect of ribonucleic acids (catalytic action) and from the effect of substrates (mass action). This hypothesis explains cellular differentiation (multicellular organism) through constitutional variations of cytoplasmic ribonucleic acids. The writer's fundamental arguments come from the study of bacterial biology, especially from the study of mutations directed by principles of desoxyribonucleic nature.  相似文献   

14.
Recent insights into the role of integrins in cancer metastasis   总被引:11,自引:0,他引:11  
Integrins have been repeatedly found involved in cancer metastasis. The past two years have seen considerable evolution in our knowledge on the role of these integrins in tumour cells. This includes the elucidation of different signalling pathways by which integrins dictate the anchorage-independent growth, survival and motility of tumour cells. Moreover, integrins may have a more complex role in cancer metastasis as they cooperate with serine proteases and metalloproteases to promote tumour cell invasion and angiogenesis. Finally, integrins favour tumor cell extravasation.  相似文献   

15.
Summary Thein vitro anti-acetylcholinesterase properties ofbis-(dimethylamino-3-phenoxy)-1-3 propane dimethiodide (2842 CT) of two phenolics derivatives (3443 CT and 3116 CT) and of the two corresponding carbamic esters (3152 CT et 3113 CT) have been compared using human red blood corpuscles as enzyme source; under specified conditions, the Cl-50 are respectively 8 × 10–7 M for 2842 CT, 3.5 × 10–9 for the two phenolic compounds, and 1.5 × 10–9 for the carbamic esters. The potencies of these phenols are very close to those of the carbamates, being a bit higher or lower depending on the concentration of the inhibitor and on the time of the readingThe two phenolic compounds, like 2842 CT, react readily with the enzyme contrarily to the carbamic esters which combine slowly. On the other hand the inhibition by the phenolic derivatives is as stable against washing as that by the carbamates. The carbamates, but not the phenols, show the slow displacement phenomenon.Some of these characteristics are compatible with the hypothesis that carbamic compounds could act through liberated phenolic functions but others indicate that carbamic groups have a role of their own.  相似文献   

16.
The recent advances in surgery and radiation therapy have significantly improved the prognosis of patients with primary cancer, and the major challenge of cancer treatment now is metastatic disease development. The 5-year survival rate of cancer patients who have distant metastasis at diagnosis is extremely low, suggesting that prediction and early detection of metastasis would definitely improve their prognosis because suitable patient therapeutic management and treatment strategy can be provided. Cancer cells from a primary site give rise to a metastatic tumor via a number of steps which require the involvement and altered expression of many regulators. These regulators may serve as biomarkers for predicting metastasis. Over the past few years, numerous regulators have been found correlating with metastasis. In this review, we summarize the findings of a number of potential biomarkers that are involved in cadherin–catenin interaction, integrin signaling, PI3K/Akt/mTOR signaling and cancer stem cell identification in gastrointestinal cancers. We will also discuss how certain biomarkers are associated with the tumor microenvironment that favors cancer metastasis.  相似文献   

17.
Connexin 43 (Cx43) hemichannels establish local signaling networks via the release of ATP and other molecules, but their excessive opening may result in cell death. Hence, the activity of Cx43-hemichannels ought to be critically controlled. This involves interactions between the C-terminal tail (CT) and the cytoplasmic loop (CL), more particularly the L2 domain within CL. Previous work revealed an important role for the last nine amino acids of the Cx43 CT by targeting the L2 domain, as these nine amino acids were sufficient to restore the activity of CT-truncated Cx43-hemichannels. However, we discovered that deletion of the last 19 amino acids of the CT only partially lowered the binding to the L2 domain, indicating that a second L2-binding region is present in the CT. We here provide evidence that the SH3-binding domain is another CT region that targets the L2 domain. At the functional level, the SH3-binding domain was able to restore the activity of CT-truncated Cx43-hemichannels and alleviate the inhibition of full-length Cx43-hemichannels by high intracellular Ca2+ concentration ([Ca2+]i) as demonstrated by various approaches including patch clamp studies of unitary Cx43-hemichannel activity. Finally, we show that in full-length Cx43-hemichannels, deletion of either the SH3-binding domain or the CT9 region suppresses the hemichannel activity, while deletion of both domains completely annihilates the hemichannel activity. These results demonstrate that the Cx43 SH3-binding domain, in addition to the CT9 region, critically controls hemichannel activity at high [Ca2+]i, which may be involved in pathological hemichannel opening.  相似文献   

18.
Summary I. Tarcsay's modification of Piotrowski's ten Rorschach signs for the diagnosis of organic and endogenous psychoses was tested on the Rorschach records of 105 genuine epileptics, 50 schizophrenics, 50 psychopaths, and 22 neurotics. The signs were found to give a positive diagnosis of psychosis in about 80% of the true cases of psychoses, but also in 45% of the psychopaths and neurotics, so that they hardly can be used for differential diagnosis. Tarcsay's schizophrenia signs and the neurosis signs of Miale and Harrower-Erickson proved to have still less diagnostic value.  相似文献   

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