34例髓性骨肉瘤侵袭骺板的影像学表现

目的：观察髓性骨肉瘤侵袭骺板的影像学表现,评价各种影像检查方法的优势,为髓性骨肉瘤保肢术提供准确的影像学依据.方法：分析经术后病理证实的34例髓性骨肉瘤侵袭骺板患者术前的普通X线、CT、MRI资料,探讨不同检查方法的影像学表现及骨肉瘤影像学特点.结果：髓性骨肉瘤侵袭骺板的影像学表现主要为骺板连续性的中断.普通X线的诊断符合率为44.12%（15/34）,CT为64.71%（22/34）,MRI为94.12%（32/34）.X线与CT相比较P＞0.05;X线与MRI相比较P＜0.01;CT与MRI相比较P＜0.01.结论：MRI的诊断符合率显著高于X线和CT,MRI图像能够显示髓性骨肉瘤对骺板的侵袭情况,为术前明确髓性骨肉瘤是否已侵袭骺板提供准确依据.     

原发性甲状旁腺功能亢进骨病的影像学分析（附12例报告）

目的：探讨原发性甲状旁腺功能亢进症骨病的常见影像学表现及特征性表现,以提高本病影像诊断正确率。材料与方法：回顾性分析12例经手术病理证实的原发性甲状旁腺功能亢进症骨病患者的影像学资料。结果：所有病例均为多骨受累,10例病变部位有多种影像学表现并存。其中普遍性骨质疏松12例,骨吸收破坏9例,纤维囊性骨炎5例,骨质软化3例,病理性骨折2例,2例儿童患者出现长骨干骺端增宽、凹陷及长骨骺板下见相对高密度区的特殊表现。结论：原发性甲状旁腺功能亢进常为多骨受累。多部位、广泛性骨膜下骨吸收对诊断原发性甲状旁腺功能亢进有重要价值。儿童患者有不同于成人的特殊影像学表现。     

长骨骨端囊样骨肿瘤及肿瘤样病变的CT分析

目的：探讨长骨骨端囊样骨肿瘤及肿瘤样病变的CT诊断价值。材料与方法：对资料完整曾行CT检查并经活检或手术病理证实的长骨骨端囊样骨肿瘤及肿瘤样病变45例进行回顾性分析。结果：45例中骨肿瘤29例,其中良性肿瘤24例,恶性5例,肿瘤样病变16例。良性肿瘤包括：巨细胞瘤12例,软骨母细胞瘤4例,骨样骨瘤,软骨粘液样纤维瘤各3例,内生软骨瘤及骨母细胞瘤各1例,恶性肿瘤包括：恶性巨细胞瘤、软骨肉瘤各2例,纤维肉瘤1例,肿瘤样病变包括：骨囊肿7例,骨纤维异常增殖症6例,动脉瘤样骨囊肿3例。发病部位包括骺板闭合前28例（其中骨骺4例,干骺端24例）闭合后骨端17例,主要CT表现为端囊样骨破坏,包括膨胀性改变34例伴皮质断裂13例,骨性包壳形成21例,瘤内钙化13例,液－液平2例,骨膜反应及软组织增厚（或肿块）分别为5例和4例,结论：CT能清晰显示X线平片不能显示的“囊”壁、“囊”内及周围结构的细微表现,因而具有重要的诊断价值。但因表现有重叠,定性诊断有一定限度。     

骶骨肿瘤的CT影像表现

目的 分析骶骨肿瘤的ＣＴ影像特点。方法回顾分析３０例经是证实的骶骨肿瘤影像学特点。结果 ３０例骶骨肿瘤包括转移瘤１０例,脊索瘤５例,骨巨细胞瘤４例,神经源性肿瘤３例,软骨肉瘤３例,其它５例,其ＣＴ影像学表现各有异同。结论从发病年龄、骶骨骨质破坏的形式、是否伴有硬化边缘,有否钙化、软组织肿块等方面分析,有助于骶骨肿瘤的诊断及鉴别诊断。     

血友病性肌骨假肿瘤患者骨骼的影像学表现

目的探讨血友病性肌骨假肿瘤(HPOM)骨骼变化的影像表现。方法收集HPOM患者16例,均为男性,其中A型12例为,B型4例;轻、中度分别为1例、15例。凝血四项中活化部分凝血活酶均延长,12例凝血因子Ⅷ下降,4例凝血因子Ⅸ下降。所有患者均接受CT及MR检查。结果单发骨病变4例,多发骨病变4例,多处肌/骨病变8例。骨质破坏表现为囊样型、囊样膨胀型、纯溶骨型、骨膜增生型、骨皮质受压型。部分病变存在钙化、软组织肿块,骨病变与软组织病变可相连或不连。结论 HPOM患者骨骼影像学变化具有多样性,其CT密度或MR信号改变具有不同时期血肿特征。     

小儿慢性骨骺损伤MRI诊断价值探讨

目的:探讨MRI检查对小儿骨骺慢性损伤的诊断价值。方法:17例小儿骨骺损伤6个月后同时行X线、MRI检查,其中4例行CT检查,对影像检查结果相互对照。结果:隐性骨骺损伤X线表现为骺线轻度增宽,CT表现为局限性骨质吸收,MRI表现为生长板区带状长T1、长T2信号,生长板相邻骨质轮廓不光滑。骨骺滑脱X线表现为骨骺半脱位、骺线增宽;CT表现为骺线增宽,骺线两侧骨质轻度硬化;MRI表现为骨骺半脱位,生长板增宽,T2WI信号升高。骨桥形成X线和MRI均显示骨骺和干骺端之间骨桥相连,骺线(或生长板)局限性消失,骨骺和干骺端短缩。结论:轻微骨骺损伤宜采用MRI诊断,骨骺滑脱X线、CT及MRI均可明确诊断,骨桥形成X线、MRI均有特征性表现。     

颌骨肿瘤及肿瘤样病变的CT表现及其临床意义

目的探讨颌骨肿瘤及肿瘤样病变的CT表现及其临床意义。方法回顾颌骨肿瘤及肿瘤样病变36例,与病理对照,分析各类病变的CT表现特征。结果骨肉瘤1例,CT表现为不规则软组织肿块,呈溶骨性骨质破坏,肿块内有瘤骨形成。良性肿瘤及肿瘤样病变6例,为边缘规则肿块,无钙化、瘤骨及骨膜反应。成釉细胞瘤6例,为边缘规则的多房或单房状肿块,骨质膨胀性破坏。颌骨囊肿21例,其中根尖囊肿12例,含牙囊肿9例,表现为边缘光滑囊性低密度区,内含有牙根或牙冠。骨纤维异常增殖症2例,均为骨质膨胀性破坏,其内骨结构紊乱,正常骨小梁消失。结论各类颌骨肿瘤及肿瘤样病变有不同的影像学特点,CT扫描对颌骨肿瘤及肿瘤样病变定性诊断及侵犯范围的准确评估有重要意义,对治疗计划的制订有重要的参考作用。     

骨尤文肉瘤的影像诊断探讨

目的　探讨骨尤文肉瘤的影像诊断及提高其影像诊断水平。方法　回顾性研究了20例经手术或/和病理证实的骨尤文肉瘤的平片、CT和MRI表现并做了影像学分型。结果　根据影像学表现,把骨尤文肉瘤分为三型(硬化,溶骨和混合)。本组病例,硬化型、溶骨型和混合型分别占20%,50%和30%。结论　实施影像综合诊断方法能提高骨尤文肉瘤的诊断水平。     

肺炎型肺癌的影像诊断与病理分析

目的:探讨肺炎型肺癌的影像特征并与病理对照,提高对炎症型肺癌的诊断水平.材料与方法:对照病理分析46例肺炎型肺癌的临床影像资料.结果:46例肺炎型肺癌中,支气管肺泡癌38例,腺癌8例.影像表现分为6型:边缘不清云絮状肿块影9例,云絮状影伴周边结节11例,9例为肺段分布实变影,8例为肺叶及肺段实变伴空泡及蜂窝状影,8例为肺炎纤维样化及肿块,1例为混合阴影.影像学特点范围逐渐扩大的云絮状阴影或实变影逐渐进展为结节或肿块伴云絮状影、纤维化、蜂窝状影及肿块,以及出现淋巴及远处转移.结论:肺炎性肺癌影像学表现多样性,观察影像变化具有一定特征性和诊断价值.     

颌面部骨源性肿瘤与类肿瘤病变的CT表现

目的回顾性分析颌面部骨源性肿瘤与类肿瘤病变的CT表现,旨在提高对此类病变CT表现的认识.方法回顾颌面部骨源性肿瘤与类肿瘤病变20例,与病理对照,分析各类病变的影像学特点.结果恶性肿瘤8例,CT表现为不规则软组织肿物,其中骨肉瘤3例,明显溶骨性骨质破坏3例,肿物内均有瘤骨形成;软骨肉瘤3例,局部有骨质破坏,肿物内有钙化灶者2例,有瘤骨及瘤软骨形成者1例;尤文氏肉瘤1例,内见钙化;良性肿瘤及类肿瘤病变7例,为边缘规则肿物,未见钙化、瘤骨及骨膜反应.成釉细胞瘤5例,为边缘规则的分房状肿物、骨质膨胀性破坏4例,广泛侵犯1例.骨纤维异常增殖症4例,均为多骨膨胀性改变,其内骨结构紊乱,正常骨小梁消失.结论各类颌面部骨源性肿瘤与类肿瘤病变有不同的影像学特点.CT扫描对颌面部骨源性的肿瘤与类肿瘤病变定性诊断及侵犯范围的准确评估有重要意义.     

Determination of creatine kinase isoenzyme MB activity in serum using immunological inhibition of creatine kinase M subunit activity. Activity kinetics and diagnostic significance in myocardial infarction.

This is a new method for the determination of creatine kinase isoenzyme MB activity in serum. The method uses direct activity measurement of creatine kinase B subunit activity after blocking of CK-M subunit activity by inhibiting antibodies. The test takes no longer than 15 min. The method yields an intra-serial C.V. of 2.0-12.9%, and a C.V. from day to day of 5.5%. The detection limit is 3.4 U/l creatine kinase MB. In the 95 cases with proven myocardial infarction several types of creatine kinase MB activity kinetics could be determined. The percentage of creatine kinase MB of peak CK-total is 6-25%, with a mean of 11.1%. The amount of creatine kinase MB with respect to total CK activity after reinfarction is higher than the amount after initial infarction.     

Dissociable correlates of two classes of retrieval processing in prefrontal cortex

Although substantial evidence suggests that the prefrontal cortex (PFC) implements processes that are critical for accurate episodic memory judgments, the specific roles of different PFC subregions remain unclear. Here, we used event-related functional magnetic resonance imaging to distinguish between prefrontal activity related to operations that (1) influence processing of retrieval cues based on current task demands, or (2) are involved in monitoring the outputs of retrieval. Fourteen participants studied auditory words spoken by a male or female speaker and completed memory tests in which the stimuli were unstudied foil words and studied words spoken by either the same speaker at study, or the alternate speaker. On "general" test trials, participants were to determine whether each word was studied, regardless of the voice of the speaker, whereas on "specific" test trials, participants were to additionally distinguish between studied words that were spoken in the same voice or a different voice at study. Thus, on specific test trials, participants were explicitly required to attend to voice information in order to evaluate each test item. Anterior (right BA 10), dorsolateral prefrontal (right BA 46), and inferior frontal (bilateral BA 47/12) regions were more active during specific than during general trials. Activation in anterior and dorsolateral PFC was enhanced during specific test trials even in response to unstudied items, suggesting that activation in these regions was related to the differential processing of retrieval cues in the two tasks. In contrast, differences between specific and general test trials in inferior frontal regions (bilateral BA 47/12) were seen only for studied items, suggesting a role for these regions in post-retrieval monitoring processes. Results from this study are consistent with the idea that different PFC subregions implement distinct, but complementary processes that collectively support accurate episodic memory judgments.     

俯卧位通气对高海拔地区肺复张治疗无效急性呼吸窘迫综合征患者氧合的影响

目的 探讨俯卧位通气对高海拔地区肺复张术(RM)治疗无效急性呼吸窘迫综合征(ARDS)患者的治疗作用.方法 从海拔2260m的地区医院筛选RM治疗无效的41例ARDS患者[平均氧合指数( PaO2/FiO2)较RM前升高＜20％视为RM无效],依不同病因分为肺内源性ARDS组(ARDSp组)和肺外源性ARDS组(ARDSexp组),每组再按信封法随机分为俯卧位组和仰卧位组,即ARDSp俯卧位组(11例)、ARDSp仰卧位组(9例)、ARDSexp俯卧位组(10例)、ARDSexp仰卧位组(11例).在通气前及通气1、2、3、4h监测动脉血氧分压( PaO2)、PaO2/FiO2、静态顺应性(Cst)、气道阻力(Raw)的变化.结果 通气lh时,ARDSexp俯卧位组PaO2/FiO2( mm Hg,l mm Hg=0.133 kPa)即较通气前显著升高(157.4±40.6比129.3±48.7,P＜0.05),并随通气时间延长呈持续增高趋势,4h达峰值(219.1 ±41.1);且ARDSexp俯卧位组通气3h内PaO2/FiO2较其他3组显著增高,另3组间则差异无统计学意义.ARDSp俯卧位组、ARDSexp俯卧位组通气4h时PaO2/FiO2均较相应仰卧位组显著增高(208.8±39.7比127.4±47.1,219.1±41.1比124.9±50.8,均P＜0.05).4组通气前后Cst无显著改变,各组间差异也无统计学意义.ARDSp俯卧位组通气4h时Raw(cmH2O·L-1·s-1)较通气前显著降低(6.8±1.7比10.7±1.8,P＜0.05),且明显低于其他3组;其他3组各时间点Raw组内及组间比较差异均无统计学意义.结论 俯卧位通气作为ARDS机械通气重要策略之一,可以改善RM无效高原ARDS患者的氧合,为抢救患者赢得宝贵的时间.     

Digital imaging among medical facilities

The Department of Veterans Affairs (VA) in the USA operates a network of 172 medical centres which all utilize a hospital information system (HIS) which has been developed and is currently maintained by the VA. During the past several years, an image management and communication module has been developed, installed and clinically utilized at the Washington DC and Maryland VA Medical Centres. This image management and communication system, referred to as the decentralized hospital computer program (DHCP) imaging system, is fully integrated with a commercial picture archiving and communication system (PACS). The system is utilized to capture, archive, and display all images generated within the hospital including radiology, nuclear medicine, pathology, endoscopy, bronchoscopy, and dermatology, intraoperative photographs, ECG data, and a limited number of paper documents. The ultimate goal of the project is to have all patient text and image data available at any clinical workstation to any authorized user anywhere within the network of medical centres. Clinical requirements for an imaging workstation include ease of use, rapid and reliable access to the complete set of patient information, and images which are of acceptable quality to meet the requirements of the user and the subspecialty. Patient confidentiality and data security must be safeguarded at all times. Integration of the images with the remainder of the patient's database was found to be critical to the success of the project. The experience at the Washington and Maryland facilities suggests that an imaging system that is successfully integrated with a hospital information system can provide substantial clinical and economic benefits both within and among medical centres. Clinical acceptance and utilization of the system has been excellent, particularly in diagnostic radiology where DHCP Imaging has been interfaced to a commercial PAC system. Based upon this initial experience, the VA has begun to deploy the system throughout its large network of medical centres.     

Myocardial elastography at both high temporal and spatial resolution for the detection of infarcts

Myocardial elastography is a novel method for noninvasively assessing regional myocardial function, with the advantages of high spatial and temporal resolution and high signal-to-noise ratio (SNR). In this paper, in-vivo experiments were performed in anesthetized normal and infarcted mice (one day after left anterior descending coronary artery [LAD] ligation) using a high-resolution (30 MHz) ultrasound system (Vevo 770, VisualSonics Inc., Toronto, ON, Canada). Radiofrequency (RF) signals of the left ventricle (LV) in longitudinal (long-axis) view and the associated electrocardiogram (ECG) were simultaneously acquired. Using a retrospective ECG gating technique, 2-D full field-of-view RF frames were acquired at an extremely high frame rate (8 kHz) that resulted in high-quality incremental displacement and strain estimation of the myocardium. The incremental results were further accumulated to obtain the cumulative displacements and strains. Two-dimensional and M-mode displacement images and strain images (elastograms), as well as displacement and strain profiles as a function of time, were compared between normal and infarcted mice. Incremental results clearly depicted cardiac events including LV contraction, LV relaxation and isovolumetric phases in both normal and infarcted mice, and also evidently indicated reduced motion and deformation in the infarcted myocardium. The elastograms indicated that the infarcted regions underwent thinning during systole rather than thickening, as in the normal case. The cumulative elastograms were found to have higher elastographic SNR (SNR(e)) than the incremental elastograms (e.g., 10.6 vs. 4.7 in a normal myocardium, and 6.0 vs. 2.4 in an infarcted myocardium). Finally, preliminary statistical results from nine normal (m = 9) and seven infarcted (n = 7) mice indicated the capability of the cumulative strain in differentiating infracted from normal myocardia. In conclusion, myocardial elastography could provide regional strain information at simultaneously high temporal (>/=0.125 ms) and spatial ( approximately 55 microm) resolution as well as high precision ( approximately 0.05 microm displacement). This technique was thus capable of accurately characterizing normal myocardial function throughout an entire cardiac cycle, at the same high resolution, and detecting and localizing myocardial infarction in vivo.     

Clinical Pharmacokinetics of Morphine

Morphine, the most widely used mu-opioid analgesic for acute and chronic pain, is the standard against which new analgesics are measured. A thorough understanding of the pharmacokinetics of morphine is required in order to safely and effectively use this analgesic in a wide variety of patients with different levels of organ function. A MEDLINE search was conducted to identify literature published between 1966 and January 2002 relevant to the pharmacokinetics of morphine. These publications were reviewed and the literature summarized regarding unique and clinically important elements of morphine disposition relative to its parenteral administration (including intravenous, intramuscular, subcutaneous, epidural and intrathecal administration), absorption profile (immediate release, controlled release, and sublingual/buccal, and rectal administration), distribution, and its metabolism/ excretion. Special populations, including infants, elderly, and those with renal/liver failure, have a unique morphine pharmacokinetic profile that must be taken into account in order to maximize analgesic efficacy and reduce the risk of adverse events.