螺旋CT诊断急性肠梗阻的临床价值

目的探讨螺旋CT在急性肠梗阻的诊断中的作用。方法 65例明确诊断的急性肠梗阻病例,回顾性分析其CT表现。结果 65例肠梗阻,其中完全性22例,不完全性43例;绞窄性为4例;肠肿瘤22例,肠扭转16例,腹内外疝5例。CT显示梗阻点位于小肠31例,结肠23例,小肠结肠均有11例;梗阻近段肠腔扩张,而远端肠腔萎陷;扩张的肠腔内可见气液平。靶征、鸟嘴征、缆绳征等具有诊断价值。增强后梗阻段肠壁异常强化。结论螺旋CT可以判断有无急性肠梗阻、梗阻部位、梗阻病因以及是否绞窄,是诊断急性肠梗阻的最重要的方法之一。     

16层螺旋CT影像中漩涡征对小肠扭转的诊断价值

目的探讨16层螺旋CT影像中漩涡征对小肠扭转的诊断价值,提高多层螺旋CT诊断小肠扭转的准确率。方法对20例术前CT平扫加增强扫描出现典型漩涡征已明确诊断为肠扭转并经手术证实病例的CT资料进行分析。主要重组方法有多平面重组法(MPR)及最大密度投影法(MIP)、血管三维重建(CTA)。结果 20例肠扭转诊断均正确,主要征象有肠管的"漩涡征"(18例)和血管的"漩涡征"(19例)、"靶环征"(3例)、"鸟喙征"(4例)。结论肠系膜血管的"漩涡征"是诊断肠扭转的较为特异性征象。CTA有助于观察肠系膜血管的表现,可清楚显示小肠扭转的部位和扭转的方向;"靶环征"及肠壁强化减弱、腹水是提示绞窄性梗阻的可靠征象;多层螺旋CT扫描及三维重建对肠扭转的诊断具有重要价值。     

影像学对早期壶腹部腺Ca诊断价值探讨(附48例报告)

目的:综合分析壶腹部早期腺Ca48例病人各种影像学表现,找出其早期诊断的可靠方法。材料与方法;对照分析经手术病理证实的48例壶腹部小腺Ca的CT、超声、ERCP、PTC资料。其中胆总管下端Ca27例。乳头Ca21例。结果48例CT检查36例可见肝内外胆管扩张呈囊状、软藤状,16例肝外胆管扩张明显,肝内胆管轻度扩张。部分可见肿块影或胆总管下端截断狭窄。8例于腹膜后大血管周围可见多发肿大淋巴结。36例超生检查显示肝内胆管扩张,胆囊肿大明显,5例可见软组织肿块影。ERCP检查24例,8例可在内窥镜下看到肿块影。结论:肝内胆管及肝外胆管扩张是壶腹部腺Ca早期影像表现,特别以肝外胆管扩张、胆囊肿大明显为特征。CT、B超、ERCP、PCT均可显示,以CT显示最为可靠,ERCP可显示乳头部肿瘤的直接征像。综合影像检查可明显提高壶腹部小腺Ca的准确率。     

盆腔直接冠状面CT扫描简易方法的临床应用

目前包括螺旋CT在内的所有CT对体部扫描均为横断面扫描。Joseph和Paul等报道了冠状面直接CT扫描在体部扫描中的应用,但需特殊装置,而且国内尚未见其实际应用于盆区疾病诊断的临床报道。笔者对已在横断面CT扫描发现盆区病变而难以定位定性的病人应用简易的直接冠状面CT扫描方法(DCCT),效果相当满意,现结合典型病例报告如下:     

高分辨率CT与常规CT检查对肺小结节及早期肺癌诊断价值的对比研究

目的:对比高分辨率电子计算机断层扫描(CT)与常规CT检查对肺小结节及早期肺癌的诊断价值。方法:将2018年6月2020年1月我院收治的肺小结节及早期肺癌患者94例纳入研究。以随机数字表法将其分为观察组及对照组,每组各47例,对照组实施常规CT检查,观察组则实施高分辨率CT检查。比较两组CT肿瘤征象情况(主要包括毛刺征、分叶征、棘突征、钙化征、空泡征、支气管征、胸膜凹陷征、血管集束征),CT扫描图像质量,诊断肺小结节及早期肺癌的效能。结果:观察组各项CT肿瘤征象人数占比均高于对照组(P<0.05)。观察组CT扫描图像质量优良率为97.87%(46/47),高于对照组的72.34%(34/47)(P<0.05)。高分辨率CT诊断早期肺癌的灵敏度及准确度、特异度分别为96.67%(29/30)、95.74%(45/47)、94.12%(16/17),高于常规CT检查的74.19%(23/31)、74.47%(35/47)、75.00%(12/16)。结论:高分辨率CT检查对肺小结节及早期肺癌诊断价值显著高于常规CT检查,可作为临床肺小结节及早期肺癌诊断的有效影像学手段,值得临床应用。     

支气管扩张症的X线平片、CT和HRCT对照分析

目的:对支气管扩张的X线平片、CT和HRCT表现做一对比分析,以提高诊疗水平。方法:取病理证实支扩20例,分别摄有胸正侧位片,常规CT扫描和HRCT扫描。HRCT选薄层,大矩阵和高分辨率算法。结果:显示X光平片漏诊率高(8/20),特异性低(3/20)。CT较平片显示肺“盲区”效果好,有粘液嵌塞者,常规CT像上有时不易与血管性病变鉴别,HRCT可显示部分含气的支气管腔存在。结论:HRCT扫描诊断支扩特异性高,可与支气管造影相媲美,它不仅显示支扩范围、程度和部位。还能显示小叶中央性改变。常规CT较平片显示率高。     

猕猴腹部及盆腔结构的CT影像学观察

目的应用CT技术对成年猕猴进行断层扫描,建立猕猴腹部及盆腔CT断层扫描图谱。方法选择普通级实验猕猴6只,雌雄各半,年龄5～8岁,取头前尾后仰卧位,采用增强扫描CT技术,对其腹部及盆腔进行断层扫描,采集容积数据及对原始数据重建。通过观察、确认,精选具有解剖意义的扫描图像:腹部7张、盆腔10张(雌雄各5张),对其每个层面的主要脏器进行标注。结果 CT影像能分辨出大部分组织器官的细微变化,较大器官、大血管界面清晰,但较小器官和细小血管、神经、肌肉组织等界面尚不清晰。结论获得了健康成年猕猴腹部及盆腔的影像学图谱,为CT技术在猕猴影像学研究、疾病的临床诊断及科学实验方面的应用,提供影像学的基础资料。     

支气管扩张症的X线平片、CT和HRCT对照分析

目的：对支气管扩张的X线平片、CT和HRCT表现做一对比分析,以提高诊疗水平。方法：取病理证实支扩20例,分别摄有胸正侧位片,常规CT扫描和HRCT扫描。HRCT选薄层,大矩阵和高分辨率算法。结果：显示X光平片漏诊率高(8／20),特异性低(3／20)。CT较平片显示肺“盲区”效果好,有粘液嵌塞,常规CT像上有时不易与血管性病变鉴别,HRCT可显示部分含气的支气管腔存在。结论：HRCT扫描诊断支扩特异性高,可与支气管造影相媲美。它不仅显示支扩范围、程度和部位。还能显示小叶中央性改变。常规CT较平片显示率高。     

肺部炎性假瘤的CT影像学表现及其鉴别诊断价值

目的:分析肺部炎性假瘤的高分辨率CT影像学表现极其鉴别诊断的价值。方法:收集2012年4月-2015年4月我院收治的59例经手术病理检查证实为肺部炎性假瘤的患者为病例组,并于同一时期随机选取80例周围型肺癌患者为对照组。比较两组患者的高分辨率CT影像学特征,并分析各种影像学特征与肺部炎性假瘤的关系。结果:病例组刀切征、桃尖征及延迟期持续强化的发生率高于对照组,分叶征的发生率低于对照组(均P0.05)。多因素Spearman的秩相关分析发现,刀切征、桃尖征及延迟期持续强化与肺部炎性假瘤诊断呈正相关关系(r=0.738,0.829,0.763,均P0.05),分叶征与肺部炎性假瘤的诊断呈负相关关系(r=-0.791,P0.05)。结论:CT影像学表现中的刀切征、分叶征、桃尖征及延迟期持续强化对肺部炎性假瘤具有较高的鉴别诊断价值,可作为临床辅助诊断肺部炎性假瘤的重要影像学资料。     

CT 扫描在食管癌淋巴结转移患者预后评估中的应用价值

目的:探讨CT扫描对食管癌淋巴结转移诊断的准确率及CT扫描对预测淋巴结转移患者预后的价值.方法:选择我院收入的行食管癌根治术患者共146例,患者均行CT及腹部彩超,检查者CT及腹部彩超对食管癌淋巴结转移检测的准确率及漏诊率,检测CT淋巴结转移数、CT三分区转移情况及CT最大病变直径等CT检测与食管癌淋巴结转移相关因素.结果:CT淋巴结总检出率显著高于彩超检出率,两组对比差异有统计学意义,P＜0.05.CT检测中胸上段、胸中段总检出率显著高于彩超检出率,结果对比差异有统计学意义,P＜0.05.所有患者自手术日起计算术后1、3年生存率分别为73.3％(107/146)、47.9％( 70/146),CT 转移数≥2枚、CT三分区转移＜2区、CT最大病变直径≤3cm患者术后生存率较高,结果对比差异有统计学意义,P＜0.05.结论:CT对食管癌淋巴结转移诊断率较高,CT转移数、CT三分区转移及CT最大病变直径检测可用于评估患者术后生存率情况.     

Recent advances in the study of Kaposi's sarcoma-associated herpesvirus replication and pathogenesis

It has now been over twenty years since a novel herpesviral genome was identified in Kaposi's sarcoma biopsies. Since then, the cumulative research effort by molecular biologists, virologists, clinicians, and epidemiologists alike has led to the extensive characterization of this tumor virus, Kaposi's sarcoma-associated herpesvirus(KSHV; also known as human herpesvirus 8(HHV-8)), and its associated diseases. Here we review the current knowledge of KSHV biology and pathogenesis, with a particular emphasis on new and exciting advances in the field of epigenetics. We also discuss the development and practicality of various cell culture and animal model systems to study KSHV replication and pathogenesis.     

The structure, reproduction and taxonomy of Vidalia and Osmundaria (Rhodophyta, Rhodomelaceae)

Comprises species occurring mostly in subtidal habitats in tropical, subtropical and warm-temperate areas of the world. An analysis of the type species, V. spiralis (Sonder) Lamouroux ex J. Agardh, a species from Australia, establishes basic characters for distinguishing species in the genus. These characters are (1) branching patterns of thalli, (2) flat blades that may be spiralled on their axis, (3) width of the blade, (4) primary or secondary derivation of sterile and fertile branchlets and (5) position of sterile and fertile branchlets on the thalli. Application of the latter two characters provides an important basic method for separation of species into three major groups. Osmundaria , a genus known only in southern Australia, was studied in relation to Vidalia , and its separation from the Vidalia assemblage is not accepted. Species of Vidalia therefore are transferred to the older genus name, Osmundaria. Two new species, Osmundaria papenfussii and Osmundaria oliveae are described from Natal. Confusion in the usage of the epithet, Vidalia fimbriala Brown ex Turner has been clarified, and Vidalia gregaria Falkenberg, described as an epiphyte on Osmundaria pro/ifera Lamouroux, is revealed to be young branches of the host, Osmundaria prolifera.     

New or rare chromosome counts in Artemisia L. (Asteraceae, Anthemideae) and related genera from Kazakhstan

Fifteen chromosome counts of six Artemisia taxa and one species of each of the genera Brachanthemum, Hippolytia, Kaschgaria, Lepidolopsis and Turaniphytum are reported from Kazakhstan. Three of them are new reports, two are not consistent with previous counts and the remainder are confirmations of very scarce (one to four) earlier records. All the populations studied have the same basic chromosome number, x = 9, with ploidy levels ranging from 2x to 6x. Some correlations between ploidy level, morphological characters and distribution are noted.     

肝癌中HBV和HCV基因和抗原的分布及意义

采用原位分子杂交方法检测HCV RNA及HBV X基因;采用免疫组织化学方法研究HCV核心抗原,非结构区C33c抗原及HBxAg在肝细胞肝癌中的定位及分布.结果表明(1)HCV RNA、HBV X基因在肝细胞肝癌组织检出率分别为40%(55/136)和82%(112/136).HCV RNA定位于癌细胞的胞浆内,阳性细胞呈散在、灶状及弥漫分布三种形式;HBV X基因在肝癌细胞中的分布呈胞浆型、核型及核浆型,阳性细胞也呈上述三种分布形式;(2)HCV C33c抗原、核心抗原在肝细胞肝癌中的阳性率为81%(133/164)及86%(141/164).C33c抗原定位于癌细胞及肝细胞的胞浆内;核心抗原既定位于癌细胞核中,又可定位于胞浆中.C33c抗原阳性细胞以灶状分布为主;而核心抗原阳性细     

Selection with two alleles and complete dominance

For a plant selection model with frequency-independent viabilities, fertilities and selfing rates, it is shown that apart from global fixation, for certain parameter combinations a protected polymorphism and facultative fixation (either allele may become fixed according to initial frequencies) may both occur. Facultative fixation requires different selling rates for the dominant and recessive type. Protection of the polymorphism requires resource allocation for male and female function. In this connection the problem of purely genetically caused population extinction is discussed.
For general frequency dependence and regular segregation, the chances for establishment of a completely recessive gene are compared to those of a completely dominant gene. It is proven that the process of establishment of the recessive gene, despite a fitness advantage, may be considerably endangered by drift effects if random mating prevails. The recessive gene may reach the same effectivity in establishment as a dominant gene, only if the recessive homozygote mates exclusively with its own type during the period of establishment.