超声监护下免疫抑制大鼠肝癌模型的建立

目的　用超声监测免疫抑制大鼠肝癌模型的建立情况。方法　将CBRH 7919大鼠肝癌细胞注入经60 Co照射和氢化可的松联合免疫抑制的 1只大鼠皮下 ,2周后将生成的肿块接种于免疫抑制的 2 0只大鼠肝内。超声下观察肝内肿块的灰阶和彩色多普勒表现。 2周后处死动物 ,并对肝内肿块做常规病理检查。结果　 3只肝内接种的大鼠在实验中死亡 ,余 17只接种 2周后超声检查均可见肝内肿块生成 ,肿块直径平均为 (1.0 2± 0 .15 )cm。大鼠肝癌原位模型成功率为85 %。病理证实肿块均为肝细胞癌。结论　通过免疫抑制可建立大鼠CBRH 7919肝细胞癌模型 ,超声可监测此模型的生长状况。这为肝癌影像学诊断和局部治疗提供了一种较理想的肝细胞癌模型。     

大鼠种植性CBRH-7919肝癌模型的MRI、数字减影血管造影及病理学表现

背景:大鼠种植性CBRH-7919肝癌模型是肝癌实验性治疗和影像学诊断研究重要的工具,但模型建立后如何对模型进行检测和验证鲜有报道。目的:通过彩色超声、MRI及肝动脉血管数字减影血管造影检查的方法来检测和验证Wistar大鼠种植性CBRH-7919肝癌模型,并探讨大鼠种植性CBRH-7919肝癌模型的影像学及病理表现。方法:CBRH-7919大鼠肝癌细胞瘤株接种裸鼠双侧肩胛部皮下,再将生成的肿瘤组织在开腹直视下移植接种于成年Wistar大鼠肝脏内,建立大鼠种植性CBRH-7919肝癌模型。模型建立4周后用彩超检查、筛选建模成功的Wistar大鼠进行MRI检查、肝动脉血管数字减影血管造影及病理学检查。结果与结论:在建模成功的35只大鼠中,超声检查发现37个结节,MRI检查发现肝脏内共41个结节,较超声增加4个;最小的结节约3mm,最大约8mm。MRI扫描显示T1WI表现为低信号,T2WI及脂肪抑制序列表现高信号。肝动脉血管数字减影血管造影均表现由肝动脉供血的富血供结节。光学显微镜下观察可见肿瘤细胞呈巢状或条块状排列,周围伴行多条血管,肿瘤细胞体积大小不一致,核大而浓染,细胞质少,异型性明显。结果表明彩超和核磁共振扫描是大鼠肝癌检查简单而有效的方法,肝动脉血管数字减影血管造影可以了解肿块的供血动脉及其血供情况。通过对Wistar大鼠种植性肝癌模型的MRI及肝动脉血管数字减影血管造影表现能反映肿瘤的病理形态学和生物学行为改变。     

大鼠种植性CBRH-7919肝癌模型的MRI、数字减影血管造影及病理学表现

背景：大鼠种植性CBRH-7919肝癌模型是肝癌实验性治疗和影像学诊断研究重要的工具,但模型建立后如何对模型进行检测和验证鲜有报道。目的：通过彩色超声、MRI及肝动脉血管数字减影血管造影检查的方法来检测和验证Wistar大鼠种植性CBRH-7919肝癌模型,并探讨大鼠种植性CBRH-7919肝癌模型的影像学及病理表现。方法：CBRH-7919大鼠肝癌细胞瘤株接种裸鼠双侧肩胛部皮下,再将生成的肿瘤组织在开腹直视下移植接种于成年Wistar大鼠肝脏内,建立大鼠种植性CBRH-7919肝癌模型。模型建立4周后用彩超检查、筛选建模成功的Wistar大鼠进行MRI检查、肝动脉血管数字减影血管造影及病理学检查。结果与结论：在建模成功的35只大鼠中,超声检查发现37个结节,MRI检查发现肝脏内共41个结节,较超声增加4个;最小的结节约3mm,最大约8mm。MRI扫描显示T1WI表现为低信号,T2WI及脂肪抑制序列表现高信号。肝动脉血管数字减影血管造影均表现由肝动脉供血的富血供结节。光学显微镜下观察可见肿瘤细胞呈巢状或条块状排列,周围伴行多条血管,肿瘤细胞体积大小不一致,核大而浓染,细胞质少,异型性明显。结果表明彩超和核磁共振扫描是大鼠肝癌检查简单而有效的方法,肝动脉血管数字减影血管造影可以了解肿块的供血动脉及其血供情况。通过对Wistar大鼠种植性肝癌模型的MRI及肝动脉血管数字减影血管造影表现能反映肿瘤的病理形态学和生物学行为改变。     

超声引导下微波消融治疗小肝癌疗效观察

【目的】对超声引导下微波消融治疗小肝癌的疗效进行研究。【方法】应用超声引导微波消融治疗32例小肝癌患者,共计42个癌结节,1月后应用超声造影检查。【结果】所有病倒治疗后1月超声造影,42个肿块中,其中35个肿块内血流消失,各个时相呈无回声增强。7例肿块内血流减少,未灭活部分动脉相高回声增强,门脉相及延迟相低回声增强,灭活部分各时相无增强。病人治疗后全身情况好转,症状减轻或消失,AFP和肝功能好转,未发生严重并发症。【结论】超声弓1导微波治疗对小肝癌的治疗有较好的疗效,安全实用。     

肝肿瘤实时灰阶超声造影实验研究

目的 :评价实时灰阶超声造影在诊断兔肝肿瘤中的价值。方法 :9只肝内接种 VX2 肿瘤的新西兰白兔行常规超声检查及实时灰阶谐波超声造影 ,造影剂选用意大利的 Sono Vue TM。观察肿瘤的动态增强表现并比较造影前后检出的肿瘤数目 ,并与病理对照。结果 :常规超声检出肿块 9个 ,检出率 2 5.7% (9/ 3 5) ,造影早期观察到三种增强类型 ,2个肿块为整体增强 ,5个肿块为周边部环状增强 ,2个为不均匀增强 ,未发现无增强型。超声造影共检出肿块 3 0个 ,检出率 85.7% (3 0 / 3 5)。超声造影的检出率明显高于常规超声。超声造影检出的的最小肿瘤为 2 mm× 3 mm。结论 :实时灰阶超声造影有助于提高肝肿瘤的检出率及反映血供状况     

超声造影对进展期胃癌肝转移的评价

目的 评价超声造影在诊断进展期胃癌肝转移中的价值.方法 对206例进展期胃癌患者运用超声造影技术对胃癌病灶进行检查的同时进行肝超声造影检查,观察肝超声造影增强情况,并与二维超声结果比较.结果 206例进展期胃癌患者二维超声检查共发现21例(85个)肝内转移性病变,而超声造影检查发现28例(147个)肝内转移性病变,新增7例(41个)二维超声检查均未发现肝内转移性病灶,而在胃癌超声造影检查同时发现肝内多个低增强才得到诊断,重新回到二维检查程序还是不能发现病灶.超声造影检查对肝转移灶的检出率显著高于二维检查(10.2%vs13.6%,X2=5.143,P＜0.05).结论 超声造影可弥补二维超声的不足,可作为进展期胃癌肝转移的首选检查方法之一.     

经静脉注射FX530对实验性兔VX2肝癌超声造影的研究

目的评价经静脉注射新型声学造影剂ＦＸ５３０观察实验性兔ＶＸ２肝癌的效果。方法先制作兔ＶＸ２肝癌模型１５只,共２０个肿瘤结节。经静脉注射ＦＸ５３０后观察兔肝内正常结构和肿瘤的二维灰阶增强情况。结果造影后,兔肝实质、肝内动脉、门静脉和肿瘤血管明显增强,肿瘤组织增强较弱或不增强,肿瘤的可视性增加,并可检出微小的肿瘤结节。结论静脉注射新型声学造影剂提高了超声对肝癌的观察能力。     

灰阶超声造影对复发性肝癌的诊断价值

目的评价灰阶超声造影检查对复发性肝癌的诊断价值.方法对复发性肝癌46例与肝血管瘤20例、肝局灶性结节性增生16例,采用SonoVue行灰阶超声造影检查.所有病例均经手术或超声引导下穿刺活检病理证实.结果造影后82例肝肿瘤性病变均表现不同程度的增强.复发性肝癌多表现为快速消退型,如以快速消退型作为复发性肝癌的诊断指标,则超声造影诊断复发性肝癌的敏感性、特异性及准确性分别为93.5%、100%和96.3%,与肝血管瘤的自周围向中心结节样快速或缓慢充填,并呈持续增强型明显不同,同样与肝局灶性结节性增生多表现为动脉相快速自中心向外周放射状的持续增强也明显不同.结论灰阶超声造影对复发性肝癌的诊断有较高的敏感性、特异性及准确性.复发性肝癌由于肝内解剖与病理的特点造成其部分病例超声造影表现不典型,可能与其血流动力学及生物学特性有关,值得深入研究.     

肝肿瘤的动态灰阶超声造影时相分析

目的:应用动态灰阶超声造影技术研究肝脏占位性病变造影增强的时相变化,评价其在肝肿瘤鉴别诊断中的价值。方法:对54例共58个肝占位性病变进行动态灰阶超声造影检查。肝占位病变包括:原发性肝癌29个,转移性肝癌4个,肝血管瘤8个,肝局灶性结节性增生12个,炎性假瘤2个和血管平滑肌脂肪瘤3个。造影剂选用浓度为400mg?蛐ml的Levovist,经肘部浅静脉快速注射。结果:超声显示注射造影剂后,肝血管瘤开始增强时间[(48±12)s]明显晚于其它病变(P<0.01)。肝恶性肿瘤的增强持续时间[(68±32)s]明显短于肝良性肿瘤(P<0.01)。肝恶性肿瘤的造影特征是肿块在动脉相增强而门脉相消退;有血供的肝良性肿瘤的造影表现为增强持续时间较长,可持续整个门脉相或延迟相。结论:动态灰阶超声造影可动态显示肝肿瘤不同时相的增强情况,有助于肝肿瘤的鉴别诊断。     

转移性肝癌动脉相增强的实时超声造影与增强螺旋CT比较研究

目的比较低机械指数超声造影与增强CT显示转移性肝癌动脉相血流灌注的差异。方法对72例转移性肝癌145个病灶进行低机械指数（MI〈0.2）反向脉冲谐波实时超声造影和增强CT扫描,比较转移性肝癌病灶动脉相增强的形态,定量分析肿瘤平均灰阶/肝组织平均灰阶比值,以了解病灶增强程度。结果超声造影动脉相显示40.7%的病灶为整体增强,71%的病灶为高增强,而增强CT分别为8.9%和10.3%（P〈0.01）超声造影动脉相肿瘤平均灰阶/肝组织平均灰阶比值为2.39±1.45,增强CT为0.84±0.17（P〈0.01）。结论低机械指数超声造影在显示转移性肝癌动脉相增强方面优于增强CT,可以更好地反映转移性肝癌动脉相微血管灌注情况。     

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.