64层螺旋CT增强扫描在急诊胸部创伤中的初步应用

目的：探讨64层螺旋CT增强扫描在急诊胸部创伤中的诊断价值及临床意义。方法：18例急诊胸部创伤患者均行胸部64层螺旋CT平扫及增强扫描。采用最大密度投影（MIP）、曲面重建（CPR）和容积再现技术（VR）对胸部大血管进行重建、分析。将CT诊断结果与手术、随访复查结果进行比较。结果：18例中,CT平扫显示胸部主要损伤有：肺挫伤10例（55.56%）,血胸及肋骨骨折各9例（50%）,气胸8例（44.44%）,锁骨骨折6例（33.33%）。CT增强扫描诊断心脏大血管损伤7例,其中锁骨下动脉假性动脉瘤3例,胸主动脉假性动脉瘤2例,胸主动脉夹层和心包破裂各1例。CT增强扫描结果与手术、临床随访结果相吻合。结论：64层螺旋CT增强扫描是全面而准确地诊断急诊胸部创伤的重要影像技术,可以对CT平扫不能确定的心脏、大血管的损伤情况作出明确判断,对临床救治方案的早期确定具有重要的指导意义。     

多层螺旋CT 血管造影在脑动脉瘤中应用

目的:观察多层螺旋CT血管造影对脑动脉瘤的诊断价值.方法:对16例脑动脉瘤患者的多层螺旋CT血管造影结果进行总结分析.结果:多层螺旋CT血管造影的诊断准确性与DSA无明显差异;多层螺旋CT血管造影显示动脉瘤的部位、大小、动脉瘤颈结构及其与周围血管的关系等与手术结果基本符合.结论:多层螺旋CT血管造影对脑动脉瘤的诊断准确率高,具备十分重要的临床应用价值.     

64层MSCT血管成像对婴幼儿主动脉缩窄及离断的评价

目的:评价64层螺旋CT血管成像在婴幼儿主动脉缩窄及离断诊断中的应用价值及其准确性.方法:对临床和超声怀疑主动脉缩窄的21例患儿行胸片、心脏大血管彩超及CT主动脉成像,其中5例行DSA检查,16例进行了手术治疗.CT血管重建技术包括VR、MIP、MPR及CPR等,对主动脉缩窄程度、长度、侧枝血管显示情况进行评价,并比较原始数据、VR、MPR、MIP及CPR几种后处理方式对主动脉缩窄诊断的准确性和敏感性.结果:21例患者中,19例为主动脉缩窄,2例为主动脉离断.病变部位于左锁骨下动脉远端、动脉导管开口附近20例(95.2%),正对左锁骨下动脉1例(4.8%).病变部位位于动脉导管近段2例,动脉导管附着处3例,动脉导管远段16例.多层螺旋CTA对主动脉狭窄诊断的总体准确率和敏感性均为100%,对主动脉缩窄的显示以靶血管VR最好,其次是CPR和MPR;对侧枝血管的显示以整体VR和CPR最好,其次是MIP和MPR;而整体VR和原始轴位图像对主动脉缩窄显示较差.结论:64层MSCT血管成像各种后处理技术相结合能为主动脉缩窄及离断患者提供了更多有价值的诊断信息,有助于临床术前评估和制定恰当的治疗方案.     

64层螺旋CT三维重建技术对下肢动脉粥样硬化病变的显示

目的探讨64层螺旋CT三维重建技术对下肢动脉病变的显示。方法103例下肢动脉粥样硬化的患者行64层螺旋CT血管造影检查资料在工作站进行多种三维重建,分析其影像表现。结果103例患者均获得了成功的造影图像,2459根下肢动脉血管得到了显示。其中845根(34.4%)下肢动脉血管正常;672根(27.3%)轻度狭窄;327根(13.3%)中度狭窄;292根(11.9%)重度狭窄,323根(13.1%)下肢动脉血管闭塞。结论64层螺旋CT三维重建是又一种无创性的、可靠的、简便的检查下肢动脉粥样硬化的方法,具有较高的临床价值。     

肺动脉栓塞的64层螺旋CT血管成像技术分析

目的从技术上探讨64层螺旋CT肺动脉造影对肺栓塞的诊断的价值。方法对62例临床疑诊肺栓塞的患者行64排螺旋CT肺动脉造影检查,采用最大密度投影(MIP)、多平面重建(MPR)、曲面重建(CPR)、容积漫游(VR)及仿真内窥镜等后处理技术,分析所获得的相关CT资料。结果64排多层螺旋CT肺动脉造影可较准确、清晰、全面地显示24例累及肺动脉及其分支共152处栓子的位置、形态、范围和程度。结论64排多层螺旋CT肺动脉造影是肺栓塞及时准确无创的诊断方法,是临床诊断肺栓塞的首选筛查办法,对肺动脉栓塞的诊断具有明显的技术优势。     

64层螺旋CT对胸部创伤的诊断价值

目的:评价64层螺旋CT相对于CR片在胸部创伤诊断中的价值。方法:我院2006年1月～2008年3月收治81例胸部创伤,全部患者在伤后10min至5h进行了64层螺旋CT检查,其中58例在初次检查后12～38h内进行了CR或床旁CR检查,CT扫描采用GE LightSpeed 64层螺旋CT机,层厚0.625 mm,螺距为0.984:1。结果:81例中诊断肋骨骨折72例,肺挫裂伤65例,气胸36例,血胸53例,血气胸31例,锁骨骨折12例,肩胛骨骨折13例,皮下及纵隔积气18例,右横膈破裂2例。在同时进行过CR检查的患者中,非错位性及撕脱性肋骨、肋软骨骨折在CR上常显示不佳,而在64层螺旋CT多平面或三维重建图像上显示非常清晰。结论:64层螺旋CT多平面及三维重建对胸部创伤各种病变的检测明显优于x线平片,对临床急救计划的制定有重要的指导意义。     

64排螺旋CTA在下肢动脉闭塞及狭窄性病变中应用价值

目的：评价64排螺旋CT血管造影在下肢动脉闭塞性及狭窄性病变中应用价值。方法：采用美国GE公司生产LightSpeed VCT对52例患者进行下肢血管造影检查。扫描层厚0．625mm,管电压120KV、管电流130．205mAs,扫描时间约为10秒。图像后处理技术多采用VR、M1P、MPR、cMPR,图像分析密切结合原始轴位图像。结果：67支血管未见明确病变,CTA显示狭窄血管共77支,5支血管闭塞;狭窄≥50％,≤75％共21支;狭窄≤50％共51支。结论：64排CTA图像在发现闭塞远端血管方面优于DSA,可以清晰显示闭塞远端侧枝供血血管。随着64排螺旋CT临床广泛应用,在下肢血管疾病诊断方面的优势会得到长足发展。     

64 排螺旋CTA 在下肢动脉闭塞及狭窄性病变中应用价值

目的:评价64排螺旋CT血管造影在下肢动脉闭塞性及狭窄性病变中应用价值。方法:采用美国GE公司生产LightSpeedVCT对52例患者进行下肢血管造影检查。扫描层厚0.625 mm,管电压120 KV、管电流130-205 mAs,扫描时间约为10秒。图像后处理技术多采用VR、MIP、MPR、cMPR,图像分析密切结合原始轴位图像。结果:67支血管未见明确病变,CTA显示狭窄血管共77支,5支血管闭塞;狭窄≥50%,≤75%共21支;狭窄≤50%共51支。结论:64排CTA图像在发现闭塞远端血管方面优于DSA,可以清晰显示闭塞远端侧枝供血血管。随着64排螺旋CT临床广泛应用,在下肢血管疾病诊断方面的优势会得到长足发展。     

血管超声与64排螺旋CT血管造影在评价颈动脉狭窄中的对比研究

目的:比较血管超声与64排螺旋CT血管造影(CTA)对颈动脉狭窄的诊断价值。方法:选取2014年12月到2015年12月我院收治的疑似颈动脉狭窄患者70例(278节段),所有患者入院1周内均行血管超声、64排螺旋CTA检查,以数字减影血管造影(DSA)为金标准,比较血管超声与64排螺旋CTA对颈动脉狭窄诊断的符合率、特异度和灵敏度。结果:血管超声和64排螺旋CTA对不同程度颈动脉狭窄诊断的符合率比较,差异均无统计学意义(P0.05);血管超声和64排螺旋CTA对颈动脉狭窄诊断的灵敏度和特异度分别为87.28%、85.71%和85.55%、90.48%,比较差异无统计学意义(P0.05)。结论:血管超声和64排螺旋CTA对颈动脉狭窄均具有较高的诊断价值。     

128层螺旋CT在透析患者上肢CT血管成像中的临床应用价值

目的：研究128层螺旋CT在透析患者上肢CT血管成像中的临床应用价值。方法：回顾性分析30例患者的64层CT图像（64层组）与39例患者128层CT图像（128层组）,对扫描数据进行三维重建后比较两组患者的动脉分支级别、血管边缘、静脉干扰评分及瘘口显示情况的差异。结果：128层组前臂与手部动脉分支级别显示评分高于64层组,差异有统计学意义（P〈0.05）;128层组肩部、上臂及前臂的血管边缘光滑度显示评分高于64层组,差异有统计学意义（P〈0.05）。结论：128层螺旋CT在透析患者上肢血管成像中血管、内瘘口以及流入流出道等细节方面显示效果更理想。     

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.