胰岛细胞瘤超声诊断价值探讨

目的：探讨超声对胰岛细胞瘤的诊断价值。方法：将超声定位的３３例与病理结果进行对照分析。结果：病理证实胰岛细胞瘤３２例,其中３例为非功能性,１例胃泌素瘤;正常胰腺组织１例。腹部超声检查定位３２例中,真阳性２１例,符合率６５．６３％;假阴性１１例,其中被术中超声检出者３例,超声引导下经皮经肝门静脉置管分段取血测胰岛素（ＰＴＰＣ）检出者３例,超声内镜检出者１例,故假阴性实为４例。１例仅作术中超声为真阴性。各种超声综合检查的敏感性、特异性及正确性分别为８７．５％,１００％,８７．８７％。阴性及阳性预期值分别为２０％及１００％。结论：多种超声综合应用可明显提高诊断正确率。     

B型超声对肾上腺醛固酮瘤定位诊断研究：漏,误诊原因分析

在经手术治疗疑有肾上腺醛固酮瘤的原发性醛固酮增多症２３８例中，超声定位诊断的敏感性、特异性和诊断正确率分别为９２．９８％、８１．２５％和９２．２１％。其中误诊（假阳性）３例占１．２６％。漏诊单瘤患者１１例，另有５例为同侧双瘤患者，超声均只检出其中之一，故共漏检肿瘤（假阴性）１６（１１＋５）个占７．０１％。文中针对失误原因进行分析讨论，旨在探寻提高诊断率的途径。     

核素显像在甲状旁腺功能亢进诊断中的价值

目的 本文探讨甲状旁腺核素显像在诊断甲状旁腺功能亢进(下称甲旁亢)中的作用，并与其他影像检查方法进行比较。方法 32例临床考虑甲旁亢患者分别进行了99Tc—MIBI核素显像、B超检查，其中13例做了CT检查，5例做了MRI检查。结果 32例患者中，PTH增高12例，以PTH结果为诊断标准，核素检查阳性13例，灵敏度91．7％，特异性90％，准确性90．6％；B超检出10例，阴性20例，其灵敏度83．3％，特异性100％，准确性93．8％；CT阳性11例，MRI阳性3例。核素检查阳性13例患者共摘除15枚腺瘤和1枚增生腺体，均经组织病理学诊断印证；核素显像阴性19例，B超检查均为阴性，CT阴性2例，MRI阴性2例。结论 ^99Tc^m-MIBI甲状旁腺核素显像是一种简单易行的方法，是甲旁亢辅助诊断手段之一，结合其他影像学检查，可进一步提高甲状旁腺腺瘤术前定位诊断准确率。     

直肠腔内超声诊断直肠肿块及判断其浸润深度的探讨

目的：为进一步提高腔内超声对直肠肿瘤的诊断水平。方法：本研究将１３３例经直肠腔内超声检查的直肠腔内、外肿块与手术及病理作对照分析。结果：恶性肿瘤１００例（占７５．１８％）,良性肿瘤１４例（占１０．５２％）,其他良性病变１９例（占１４．２８％）。共检查出１３１例,符合率９８．４９％（１３１／１３３）,２例为假阴性,无假阳性。恶性肿瘤中直肠癌９６例,腔内超声提示浸润深度与病理结果相符７８例,准确率为８１．２５％（７８／９６）,浸润深度误判１８例,占１８．７５％（其中判断过深１３例,过浅５例）。结论：腔内超声的应用为直肠肿块的检查提供了一个直接、简便、安全的新方法     

鼻咽癌细胞DNA含量的分析

目的探讨鼻咽细胞复制不同时期ＤＮＡ含量与癌细胞发生发展的关系，为建立现代化诊断方法提供资料。方法本文应用流式细胞仪（ＦＣＭ）对６４例经病理诊断为鼻咽癌（ＮＰＣ）患者的鼻咽细胞进行ＤＮＡ含量测定，并与４１例慢性咽炎患者的鼻咽细胞ＤＮＡ含量进行对照分析。结果ＮＰＣ患者中非整倍体的阳性率为８４．４％；假阴性１５．６％；假阳性７．３％。ＤＮＡ合成期（ＳＰＦ）大于３０％的阳性率为８７．５％；假阴性１２．５％；假阳性９．８％。结论应用ＦＣＭ检测肿瘤细胞周期ＤＮＡ含量，具有快速、准确、自动化程度高的优点，有较好的临床应用前景。     

床旁超声对外伤性气胸的诊断价值

目的以CT为标准比较床旁超声、仰卧位X线胸片对气胸的诊断价值。方法46例钝性胸外伤患者均作了床旁超声、仰卧位X线胸片检查，并对结果和CT片进行比较。结果31／46例（34侧）患者口检查发现气胸，其中28例（30侧）超声检查也发现，10例在仰卧位X线胸片发现，2侧超声结果假阳性患者CT检查证实为肺大泡。超声检查对气胸的敏感性88.2％（30／34侧），特异性96．6％（56／58侧），阳性预测值93．8％（30／32侧），阴性预测值93．3％（56／60侧）；而仰卧位胸片的敏感性35．3％（12／34侧），特异性100％（58／58侧），阳性预测值100％（12／12侧），阴性预测值72．5％（58／80侧）。结论本研究结果表明，床旁超声检查对外伤性气胸的诊断敏感性、准确度比仰卧位X线胸片好，和CT检查结果相似。     

绞窄性小肠梗阻的超声诊断价值

目的 探讨腹部Ｂ超对早期绞窄性肠梗阻的诊断价值。方法 对７４例经手术或保守治疗证实的小肠梗阻患者进行分析。其中绞窄性肠梗阻１６例,单纯性肠梗阻５８例。对比研究临床物理学诊断、实验室检查（ＷＢＣ升高）、Ｘ线检查和腹部Ｂ超对绞窄性肠梗阻的诊断价值。比较各项指标的敏感性、特异性、阳性预测值、阴性预测值及符合率。结果 超声检测的敏感性为８１．３％（１３／１６）,特异性为８９．７％（５２／５８）,符合率为８     

99Tcm-MIBI和99TcmO-4显像定位诊断甲状旁腺机能亢进

目的评价99TcmMIBI双时相显像及99TcmMIBI/99TcmO-4联合显像对探测功能亢进甲状旁腺组织的临床应用价值,并与其他影像学手段进行比较。方法68例诊断或疑诊甲旁亢患者行99TcmMIBI甲状旁腺双时相显像(其中9例在一周内行99TcmO-4甲状腺显像),患者均行全身显像,其中1例行SPECT/CT融合显像,35例行B超检查,6例行CT检查。54例行手术治疗获得病理结果(甲状旁腺增生18例,甲状旁腺腺瘤25例,甲状旁腺癌7例,结节性甲状腺肿2例,甲状腺癌1例,淋巴结慢性炎症1例),其余14例临床最终除外甲旁亢。结果99TcmMIBI双时相显像阳性47例,阴性21例;99TcmMIBI/99TcmO-4联合显像阳性8例,阴性1例。核素显像经病理及临床其他检查证实真阳性47例,真阴性15例,假阳性3例,假阴性3例。灵敏度94%,特异性83.3%,准确性91.2%,阳性预测值94%,阴性预测值83.3%。结论综合运用99TcmMIBI的双时相显像、全身显像、SPECT/CT融合显像及99TcmO-4显像能进一步提高核医学对功能亢进甲状旁腺组织定性及定位诊断的准确性。     

超声检查对宫外孕诊断120例分析

目的：探讨超声检查在宫外孕诊断中的临床价值。方法：对120例临床可疑宫外孕的患者，采用经阴道二维超声、彩色多普勒（CDFI）进行检查，将超声结果与术后病理以及随访资料进行对比。结果：超声诊断宫外孕80例，经临床手术及保守治疗后确诊77例，假阳性3.9％，假阴性1．3％，诊断准确率为94．8％。结论：超声检查在宫外孕诊断中能够提供有价值的信息，可对绝大部分宫外孕进行准确诊断。     

线阵超声内镜对胆总管结石的诊断价值研究

目的探讨线阵超声内镜对胆总管结石的诊断价值。方法对35例腹部B超发现胆总管扩张,临床怀疑胆总管结石的患者行线阵超声内镜检查,并在3d内再行ERCP及乳头扩约肌切开胆总管取石,以取石的结果计算线阵超声内镜诊断的准确率、灵敏度、特异度、阳性预测值、阴性预测值及Youden指数。结果35例患者中,经线阵超声内镜检查及胆总管取石结石均阳性者22例,阳性率为62.8％（22／35）,均阴性者12例。线阵超声内镜检查有1例假阳性,无假阴性。与胆总管取石比较,线阵超声内镜诊断胆总管结石的准确率为97．1％,灵敏度为100％,特异度为92．3％,阳性预测值为95．6％,阴性预测值100％,Youden指数为92．3％,且未出现并发症。结论线阵超声内镜检查是诊断胆总管结石安全而可靠的方法。     

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.