原发性透明细胞型肝癌的CT和MRI诊断

目的 探讨原发性透明细胞型肝癌的影像表现,评价CT和MRI对该病的诊断价值.方法 回顾性分析19例经手术病理证实的原发性透明细胞型肝癌的CT和MRI表现.13例行CT平扫和动态增强扫描,8例行MR T1WI、T2WI和动态增强扫描.结果 CT平扫13例病灶均为低密度,其中9例病灶内部见不规则的更低密度影.增强后动脉期所有病灶均有强化表现,9例病灶不均匀强化,病灶中心有无强化的低密度区.门静脉期11例病灶呈相对低密度,2例呈等密度.3例可见环形强化的包膜.MR T1WI上5例病灶为低信号,3例为稍高信号.T2WI上5例病灶为混杂高信号,3例为等、低信号.MRI增强动脉期所有病灶均有显著强化.门静脉期和延迟期7例病灶为相对低信号,1例为等信号.2例病灶见环形强化的包膜.结论 CT和MRI可显示原发性透明细胞型肝癌的特征性表现,有助于提高该病的诊断准确性.     

肝细胞腺瘤的影像表现及与病理结果的对照分析

目的 探讨肝细胞腺瘤的影像特征及其相关病理基础.方法 回顾性分析经手术病理证实的12例肝细胞腺瘤患者资料,根据肿瘤的病理特性分为脂肪变性型、炎细胞浸润伴血窦扩张型、异型细胞型和不典型肝细胞腺瘤4类亚型,分析不同病理亚型肝细胞腺瘤的CT及MR表现特征并与病理结果进行对照分析.结果 脂肪变性型共4例,其中2例行CT扫描,1例行MR扫描,1例同时行CT加MR扫描.CT平扫1例,表现为低密度;增强扫描3例,动脉期、门静脉期及延迟均为低密度;MR平扫2例,T1WI正相位均为等信号,T1WI反相位均为低信号,T2 WI均为中低信号;增强扫描1例,动脉期、门静脉期及延迟期均为低信号.炎细胞浸润伴血窦扩张型共2例,均行MR扫描,1例行CT扫描;CT平扫为低密度且CT三期动态增强均表现为高密度;MR平扫2例,T1WI 1例为等信号、1例为低信号,T2WI均为中高信号,MR增强扫描,2例三期动态增强呈不均匀渐进性持续强化,均为高信号.异型细胞型共3例,CT平扫2例,1例为均匀低密度、1例为均匀等密度;CT增强扫描3例,动脉期均为高密度,门静脉期强化程度减低(2例为高密度、1例为等密度),延迟期密度进一步减低(2例呈略高密度、1例呈略低密度);1例同时行CT及MR扫描,MR平扫T1WI为等信号,T2 WI为中高信号.不典型肝细胞腺瘤共3例,1例同时行CT和MR扫描,2例仅行MR扫描.1例CT平扫为均匀低密度,增强扫描动脉期为高密度,门静脉期为等密度,延迟期为略高密度;3例MR平扫,T1WI为2例为等信号,1例为中高信号(1/3例);T2WI为中高、中低、等信号各1例;增强扫描2例,动脉期均为高信号,门静脉期呈中低、中高信号各1例,延迟期呈等信号和中低信号各1例.结论 肝细胞腺瘤的影像特征与其病理组织特征密切相关.     

肝脏上皮样血管内皮瘤的CT和MRI表现

目的 总结肝脏上皮样血管内皮瘤(HEHE)的CT和MRI表现.方法 搜集经手术或穿刺活检后病理证实的HEHE 11例,所有的病例均行CT检查,其中5例行CT平扫及双期增强扫描(动脉期+门静脉期),其他6例行CT平扫及三期增强扫描(动脉期+门静脉期+延迟期).11例中有5例加做MRI平扫及动态增强扫描.回顾性分析病变的生长方式、分布特点、密度(信号)特点、强化方式及邻近组织情况.结果 11例均表现为肝内多发病灶,大部分病灶位于肝包膜下,根据生长方式分为三型:结节型(5例),匍匐生长型(1例)和混合型(5例).CT平扫,病灶均呈低密度,直径＞2 cm的病灶内见类圆形更低密度.MRI平扫:病灶呈T1WI低信号、T2WI高信号,直径＞2 cm的病灶信号不均匀(T1WI内见更低信号,T2WI内见更高信号).其他影像学征象包括“棒棒糖征”(6例)、包膜退缩征(6例).增强扫描:病灶直径＜1 cm的表现为轻度较均匀强化;病灶直径为1～2 cm主要表现为轻度较均匀强化;病灶直径＞2 cm的多为不均匀渐进性强化.结论 HEHE的CT和MRI表现具有一定的特征性,其强化方式与病灶的大小相关.     

原发性肝神经内分泌癌的影像表现

目的 探讨原发性肝神经内分泌癌的CT和MRI表现,提高影像诊断水平.方法 回顾性分析经手术病理证实的6例肝原发性神经内分泌癌患者资料,术前4例行CT平扫及增强扫描,2例行MR平扫及增强扫描.结果6例中肿瘤呈多发1例,表现为1个大肿瘤伴周围多个小结节灶,其余5例均为单发.CT平扫除1例病灶周边可见点状钙化外,均表现为肝内低密度占位,病灶中央见较大范围的不规则更低密度区,边界清晰.肿瘤在MR T1WI表现为不均匀低信号,T2WI表现为略高信号.增强扫描实质部分表现为早期轻中度持续强化,但强化程度有所下降,也可表现为门静脉期和延迟期呈轻度强化,中心更低密度或信号区多无明显强化;周围肝内血管呈受压推移改变,腹腔及后腹膜均未见明显肿大的淋巴结.结论CT和MRI能显示原发性肝神经内分泌癌的特征,在该病的诊断和鉴别诊断中有一定价值.     

多形性黄色星形细胞瘤影像学表现与病理学分析

目的探讨多形性黄色星形细胞瘤(PXA)的影像学及病理学表现.方法回顾性分析2003-2011年间共12例经手术病理证实的 PXA 病人组织病理学、免疫组织化学和影像学资料.12例病人均行 MRI 平扫及增强检查,其中5例行 CT 平扫,2例行 CT 平扫和增强扫描.结果12例病人病理组织学均可见不同程度囊变,瘤细胞呈明显多形性,肿瘤中有淋巴组织浸润,少有坏死,核分裂少或无.其中10例表达 CD34.12例病人肿瘤均为单发,位于幕上.MRI 平扫时实性部分 T1WI 呈等信号或稍低信号,T2WI 为等信号或稍高信号;囊性部分 T1WI呈低信号,T2WI 呈高信号.MR 增强扫描时肿瘤实性部分和壁结节明显强化.5例病人进行 CT 平扫,3例表现为低密度囊性病变伴等密度结节,2例呈低密度囊性病变,未见明显结节影;增强扫描可见明显的强化结节.结论 PXA具有一定的影像和病理学特征,综合对比分析可以确定诊断.     

原发性肝透明细胞癌的 CT 及 MRI 表现

目的：评价 CT 和 MRI 对原发性透明细胞型肝癌(PCCCL)的诊断价值。方法回顾性分析38例经手术病理证实的PCCCL 的 CT 和 MRI 表现。26例行 CT 检查,23例行 MRI 检查,其中11例同时进行了 CT 及 MRI 检查。结果CT 平扫表现为低密度(n=24,92.3%)、稍高密度(n=2,7.7%)。MR T1 WI 呈低信号(n=19,82.6%)或混杂高信号(n=4,17.4%),脂肪抑制后信号均有不同程度下降。T2 WI 病灶为高或稍高信号(n=22,95.7%),1例为等低信号(n=1,4.3%),CT/MR 动态增强后动脉期所有病灶均强化(n=38),门静脉期病灶呈相对低密度(n=35,92.1%)或稍高密度/高信号(n=3,7.9%)。肿瘤内结节状强化共14例。环形包膜样强化26例(26/38,68.4%)。结论PCCCL 既有普通型肝癌“快进快出”的强化方式和包膜样强化的特征,又有自身特点即肿瘤内结节状强化和瘤内脂肪成分。     

混合型肝脏血管平滑肌脂肪瘤的CT和MRI诊断

目的 探讨肝脏血管平滑肌脂肪瘤(hepatic angiomyolipoma,HAML)CT和MRI的诊断价值.资料与方法回顾性分析经病理证实的8例肝脏HAML的CT和MRI表现.8例均行CT平扫和多时相动态增强扫描,其中4例同时行MRI平扫和多时相动态增强扫描.结果 8例均为单发混合型HAML,CT平扫均表现为低于周围正常肝组织的混杂低密度,灶内含有不同程度的脂肪密度,CT值-40～40HU.4例MRI平扫表现为稍长T1(含短T1)、稍长T2混杂信号,T1WI上高信号在使用脂肪抑制技术后完全消失.CT与MRI多时相动态增强扫描显示动脉期病灶均呈显著不均匀强化,门静脉期6例CT、3例MRI病灶呈持续或渐进性中重度强化,高于周围正常肝实质,2例CT、1例MRI病灶轻中度强化;3例HAML见假包膜,且在门静脉期及延迟期有轻度强化.结论 CT和MRI能显示混合型HAML的特征性表现并可在术前做出准确诊断.     

螺旋CT、MR和超声在移植性肝癌生长监测中作用的实验研究

目的:研究兔VX2移植性肝癌模型的生物学特点,评价各种超声、CT、MR在肝癌检测和诊断中的作用.方法:45只新西兰大白兔在无菌条件下,接种VX2瘤组织块和生理盐水混悬液,超声、CT、MR检测肿瘤的生长和成瘤情况.结果:制模成功率为88.8%,VX2肝癌超声表现为低回声肿块,无包膜,CDFI显示肿瘤血供为高频低阻型动脉型血流频谱,CT平扫为低密度或等密度不规则性肿块;增强扫描动脉期肿瘤明显强化,呈高密度,门脉期肿瘤呈低密度,肿瘤边缘及正常肝实质强化明显,MRI T1WI表现为低信号肿块,T2WI肿瘤呈不均匀稍高信号, PD序列与T1WI相比肿瘤信号增高,肿瘤呈等信号.结论:开腹直视注入法,建立兔VX2肝癌模型成功率高,超声、CT为准确、方便的检测手段,可以动态观察肿瘤的生长情况,MRI有利于观察肿瘤的内部成分.     

小儿肝母细胞瘤的CT及MRI诊断

目的 :分析小儿肝母细胞瘤(HB)的CT及MRI图像特点,以提高影像科医师对该病的诊断准确率。方法 :收集有完整临床及病理资料的HB患儿20例,均行CT平扫+增强扫描,16例行MRI检查。结果:20例中胚胎型10例,胎儿型6例,混合型4例。CT表现为类圆形肿块12例,分叶状肿块8例。CT平扫表现为边界清晰的等低或混杂密度,瘤体内部可见裂隙样更低密度,8例伴钙化,5例伴液化坏死,2例伴出血;增强扫描肿瘤动脉期肿瘤呈结节样或网格状线型强化、门脉期及延迟期呈低密度。T_1WI呈等低信号,可见包膜,T_2WI呈高信号;增强扫描肿瘤呈不均匀强化,强化程度低于正常肝实质。结论:CT及MRI可准确定位、定性HB,对HB的早期诊断和判断预后有重要价值。     

垂体脓肿的MRI和CT诊断

目的总结5例垂体脓肿的Mill和CT表现,并复习相关文献,探讨垂体脓肿的影像学诊断和鉴别诊断。资料与方法5例垂体脓肿均经手术病理证实。5例术前均行MR平扫和增强,2例行CT平扫和增强。结果5例均表现为垂体腺增大,向鞍上突出。2例CT平扫呈低密度;3例MR平扫T1WI呈低信号,T2WI呈脑脊液样高信号,2例T1WI与脑实质信号类似,T2WI呈稍高信号。2例CT增强扫描未显示明显强化征象;5例MR增强扫描均呈环形强化,4例环壁薄且均匀,1例环壁较厚。结论环形强化是垂体脓肿的影像学表现特点,MR增强扫描显示这种环形强化比CT增强扫描更优越。     

Physiologic and pathologic calcifications and ossifications in the face and neck

The aim was to give a systematic presentation of physiologic and pathologic calcifications and ossifications in the face and neck with a special emphasis on clinical relevance. In a sometimes subacute setting one should recognize specific calcifications which often lead to important diagnoses such as fungal sinusitis or sclerosing labyrinthitis. In a more chronic situation intraocular calcifications in small children are pathognomonic for retinoblastoma. Juxtatumoral sclerosis of the laryngeal cartilage in laryngopharyngeal carcinoma is usually caused by tumor infiltration of the cartilage resulting in a higher tumor stage and, this way, has a major impact on the therapeutical strategy. Calcified lymph nodes are mainly unspecific but can be the result of tuberculosis or metastases of thyroid cancer. Cross-sectional imaging methods, most of all computed tomography, are ideally suited to reveal head and neck calcifications and ossifications, especially those which are clinically relevant.     

Head and neck infection and inflammation

This article discusses the imaging manifestations of infectious and inflammatory conditions of the head and neck. Special attention is paid to the sites, routes of spread, and complications of neck infections. Because the clinical signs and symptoms and the complications of these conditions are often determined by the precise anatomic site involved, anatomic considerations are stressed. Familiarity with the fascial layers, spaces of the neck, and the contents of each space is helpful for this discussion. The fascial layers of the neck are important barriers to infection, and once infection is established, the fascial layers play a part in directing its spread.     

幽门螺杆菌分泌与重组表达的VacA蛋白的分离纯化及其致细胞空泡效应与凋亡的对比研究

目的：分离纯化幽门螺杆菌分泌和重组表达的细胞空泡毒素抗原（ VacA）蛋白,并评价其致细胞空泡效应及致细胞凋亡效应。方法分别从幽门螺杆菌ATCC26695菌株培养上清和重组表达VacA蛋白的pQE30-VacA-E．coliM15基因工程菌中分离纯化VacA蛋白,经酸化后,以不同终浓度（5,10 ng／ml）分别与人胃腺癌AGS细胞共孵24 h,观察致空泡效应,并通过流式细胞术检测细胞凋亡。结果成功分离纯化出幽门螺杆菌分泌和重组表达的VacA蛋白;幽门螺杆菌分泌的VacA蛋白能显著引起AGS细胞的空泡样改变及凋亡（P＜0．01）,而重组表达的VacA蛋白致细胞空泡样改变及凋亡不显著（ P＞0．05）。结论幽门螺杆菌分泌的VacA蛋白有良好的空泡毒性及致凋亡效应,而重组表达的VacA蛋白无致空泡及凋亡效应,幽门螺杆菌分泌的VacA蛋白可用于VacA作用机制的研究。     

化学和生物学融合对国际武器公约履约的影响

化学武器公约（ CWC）和生物武器公约（ BWC）是为禁止生产、发展、储存和使用化学武器和生物武器而制定的国际公约。近年来,科学技术快速发展,知识交叉渗透,学科之间出现整合和融合,促进了科技进步和经济发展。其中化学和生物学融合在有力促进制药、健康卫生、绿色化学和环境保护等产业进步的同时,也对化学和生物武器公约的履约产生了重要的影响。该文综述了与化学武器和生物武器公约相关的化学和生物学融合进展,并分析其对公约履约的影响。     

Oxygen uptake and ventilation during rowing and running in females and males

This study evaluated if the ventilatory response to exercise is impaired by the cramp position of rowing. Maximal oxygen uptake (VO2max), maximal expiratory volume (VEmax), and maximal heart rate (HRmax) during rowing and running were compared in 55 males (age, mean +/- SD, 21 +/- 3 years; height 176 +/- 5 cm; body mass 72 +/- 6 kg) and 18 females (age 20 +/- 2 years; height 164 +/- 5 cm; body mass 61 +/- 4 kg). VEmax was larger during rowing than during running (males, 157 +/- 16 vs. 147 +/- 13 L min(-1); 114 +/- 9 vs. 105 +/- 11 L min(-1), P<0.01). Also VO2max was larger during rowing than during running (males, 4.5 +/- 0.5 vs. 4.3 +/- 0.4 L min(-1); females, 3.3 +/- 0.4 vs. 3.2 +/- 0.4 L min(-1), P<0.01). However, HRmax was lower during rowing than during running (males, 194 +/- 8 vs. 198 +/- 11 beats min(-1); females, 192 +/- 6 vs. 196 +/- 8 beats min(-1), P<0.05). VEmax was correlated to body mass and fat-free mass, as was VO2max. Thus, the oxygen pulse (VO2max/HRmax) was larger during rowing than during running, while the ventilatory equivalent for oxygen (VEmax/VO2max) was similar. We showed that bending the body during rowing does not seem to impair ventilation either in males or in females. The results indicate that VEmax and VO2max relate to body size and fat-free mass for both females and males. The findings indicate that the involvement of more muscles, the entrainment, and the body position during rowing facilitates ventilation and venous return and lowers maximal heart rate.     

Coracoclavicular and coracoacromial ligament calcification and ossification

Thirty-six patients with calcification or ossification at or around the coracoclavicular and coracoacromial regions were analyzed with regard to type, location, and configuration of the deposits and related clinical history. Calcification or ossification in the coracoclavicular region resulted largely from trauma (36%) or renal failure (28%). Trauma patients may develop punctate calcification or ossification but do not develop the tumoral type of calcification. About 5% of the renal failure patients had coracoclavicular ligament calcifications, one-half of which were of the tumoral type. Renal failure patients may have punctate or tumoral calcifications but do not develop ossification.     

CLIP相关技术的研究进展

在真核生物基因表达的转录后调节中,RNA结合蛋白（ RBP）起着关键作用,很多RBP的异常与人类疾病的发生密切相关。自2000年的RNA免疫沉淀和芯片分析方法（ RNA immunoprecipitation with differential display or microarray analysis , RIP-ChIP）出现以来,人们开始就RBP与RNA相互作用进行了系统而广泛的研究。经过改良和发展,基于体内实时紫外交联免疫沉淀法（ ultraviolet crosslinking and immunoprecipitation , CLIP ）、交联免疫沉淀cDNA文库高通量测序法（ high-throughput sequencing of CLIP cDNA library , HITS-CLIP）、光催化核糖核苷增强交联和免疫沉淀法（ photoactivatable-ribonucleoside-enhanced crosslinking and immunprecipitation , PAR-CLIP）以及提高个别核苷酸分辨率交联和免疫共沉淀法（ individual nucleotide resolution CLIP , iCLIP）等RIP-ChIP衍生方法相继产生,使用这些方法,可以解析RBP的RNA识别特异性,而且通过与高通量测序技术结合,可以实现转录组尺度的RBP的靶序列的鉴定,分辨率也得到极大提高。该文就RNA与蛋白的相互作用的基本原理及其研究进展、相关技术存在的问题以及发展趋势进行简要综述。     

Cross-sectional and longitudinal comparisons of self-reported and device-assessed physical activity and sedentary behaviour

ObjectivesTo examine the longitudinal associations and differences between self-reported and device-assessed physical activity (PA) and sedentary behaviour (SB), using a multifaceted statistical approach.DesignLongitudinal measurement burst.MethodsIn total, 52 university students (78% female) aged 18–38 years (mean = 21.94 ± 4.57 years) participated. The study consisted of three blocks of six days of measurement, during which participants wore an accelerometer on their wrist for the entire block, and self-reported their PA over the 6 days at the end of each block.ResultsMeaningful latent differences between methods were observed for moderate PA and SB across all three assessment periods, such that participants underreported the time spent in each activity. Bland–Altman plots revealed a positive mean difference for vigorous PA, with over-reporting increasing as mean levels increased. Negative mean differences were observed for all other intensities. Underreporting of moderate PA increased as the mean level increased, whereas for light PA and SB, underreporting decreased at high levels. Repeated measures correlations revealed a meaningful association for vigorous PA only, suggesting that as self-reported minutes increase so too do device-measured minutes.ConclusionsWe found evidence of cross-sectional and longitudinal differences and weak associations between self-reported and device-assessed PA and SB. Future work is needed to enhance the quality of self-reported methods to assess PA and SB (e.g., face and content validity), and consider improvements to the processing of device-based data.     

Old and dangerous: Prison and dementia

Older prisoners are the fastest growing group of prisoners in many countries. The purpose of this study is to explore the phenomenon of detention of persons suffering from dementia. Medline searches were conducted for relevant articles, chapters and books published until August 2016. Search terms included dementia, elderly, prison and criminal. Publications found through this indexed search were reviewed for further relevant references. As results, there is a lack of data about elderly with dementia in prisons. Given the rise in the average age, it is reasonable to hypothesize that the number of older prisoners is growing. Moreover, some elderly are imprisoned with a concomitant cognitive impairment or psychiatric disorder while others will develop such diseases once incarcerated. At the present time, legal and social systems seem unprepared to handle the phenomenon of dementia in prison. As proposal, health assessments for older first time offenders should become a practice inside the correctional facilities and include an evaluation for specific health issues, such as psychiatric comorbidity and cognitive impairment.