超声造影鉴别诊断可疑恶性乳腺病灶的囊实性

目的 探讨CEUS在可疑恶性乳腺病变囊实性鉴别诊断中的应用价值。方法 对277例患者共277个可疑恶性乳腺病灶进行常规超声及CEUS检查,分别做出相应诊断,并与术后病理结果比较。同时进行医师诊断信心分级。结果 277例可疑乳腺病变,CEUS较常规超声能检出更多囊性或囊实性病变(χ²=93.57,P<0.01)。CEUS后诊断者1级诊断信心和2级诊断信心明显升高(P<0.01)。结论 在可疑乳腺病变的临床超声诊断中,CEUS有助于病灶囊实性的鉴别及提高临床工作者的诊断信心。     

常规超声联合超声造影鉴别诊断乳腺良恶性肿瘤

目的 探讨常规超声(US)、CEUS以及US联合CEUS鉴别诊断乳腺良恶性肿瘤的价值。方法 回顾性分析73例单发乳腺肿块患者的US及CEUS资料。采用多元Logistic回归获得US、CEUS以及US联合CEUS诊断乳腺恶性肿瘤的模型方程,计算3个模型诊断乳腺恶性肿瘤的准确率、敏感度和特异度;绘制ROC曲线,评价3种方法诊断乳腺恶性肿瘤的能力。结果 US诊断乳腺恶性肿瘤的主要指标为病灶周边声晕、蟹足样边界及阻力指数(RI);采用CEUS诊断乳腺恶性肿瘤的主要指标为不均匀增强、增强后径线扩大以及相对峰值强度;US联合CEUS诊断乳腺恶性肿瘤的主要指标为病灶周边声晕、蟹足样边界、RI及不均匀增强。单独运用US和CEUS以及US联合CEUS诊断乳腺恶性肿瘤的准确率、敏感度、特异度分别为88.9%、91.4%、84.2%,87.7%、89.7%、84.6%和92.3%、97.1%、83.3%,ROC曲线下面积分别为0.96、0.90及0.98。结论 US和CEUS鉴别诊断良恶性肿瘤的能力相当,二者联合应用可提高诊断水平。     

超声造影和钼钯X线对乳腺肿物良恶性的诊断效能比较

目的 探讨乳腺CEUS和钼钯X线对乳腺肿物良恶性的诊断效能。方法 收集接受乳腺肿物切除的患者164例共176个病灶,患者于术前接受乳腺CEUS和钼钯X线检查,以病理结果为金标准,比较这两种方法鉴别乳腺肿物良恶性的诊断效能。结果 176个肿物中,良性63个,恶性113个。CEUS和钼钯X线鉴别乳腺肿物良恶性的ROC曲线下面积分别为0.91、0.71(Z=4.69,P<0.05)。CEUS和钼钯X线诊断乳腺恶性病变的准确率、敏感度、特异度分别为88.64%(156/176)、92.04%(104/113)、82.54%(52/63)和69.32%(122/176)、75.22%(85/113)、58.73%(37/63)。结论 CEUS鉴别乳腺肿物良恶性有较高的诊断效能。     

超微血管显像技术在鉴别诊断淋巴结良恶性中的应用

目的 探讨超微血管显像(SMI)技术对淋巴结良恶性鉴别诊断的临床应用价值。方法 回顾分析62例浅表淋巴结肿大患者的超声检查资料,并与病理结果对照,比较二维灰阶超声联合CDFI、二维灰阶超声联合SMI及CEUS鉴别诊断良性淋巴结、淋巴瘤及恶性肿瘤淋巴转移的准确率。并以CEUS为金标准,分析淋巴结内微血管分布类型。结果 62例患者共76枚浅表肿大淋巴结,其中良性淋巴结21枚,淋巴瘤32枚,恶性肿瘤淋巴结转移23枚。二维灰阶超声联合SMI与CEUS的诊断准确率均高于二维灰阶超声联合CDFI(χ²=7.91、14.04,P=0.021、0.005),而二维灰阶超声联合SMI与CEUS间差异无统计学意义(χ²=0.31,P>0.05)。CDFI及SMI与CEUS对淋巴结内微血管分布类型的一致性均较高(Kappa=0.672、0.793)。结论 SMI与CEUS对判断淋巴结内微血管分布类型具有较高的一致性,有助于提高浅表肿大淋巴结定性诊断的准确率。     

CEUS定量分析鉴别诊断乳腺肿瘤的价值及其与微血管密度的相关性分析

目的 采用CEUS时间-强度曲线(TICs)各参数鉴别良恶性肿瘤的价值及其与微血管密度(MVD)间的关系。方法 纳入获得病理诊断的患者79例,其中良性病变56例,恶性病变23 例。手术病理标本切片行免疫组织化学染色检测MVD。采用SonoLiver软件定量分析各参数与MVD关系。结果 乳腺病灶TICs的各参数在良恶性肿瘤之间比较差异无统计学意义(P>0.05);乳腺病灶的IMAX 及QOF明显高于乳腺实质,而且RT、TTP、mTT均较乳腺实质短(P <0.05)。恶性病灶MVD数目为(173.16±64.67)个/mm²,良性病灶MVD数目为(149.01±35.16)个/mm²,差异有统计学意义(P =0.04)。TICs各参数只有IMAX与MVD相关(r=0.229,P=0.048)。结论 乳腺病变CEUS定量参数的IMAX与MVD存在正相关,通过定量分析的峰值强度参数可以初步评估乳腺肿瘤内微血管密度。     

二维超声、多普勒超声及弹性成像鉴别诊断乳腺肿块

目的 探讨二维超声、多普勒超声及超声弹性成像(UE)对乳腺肿块良恶性的鉴别诊断价值。 方法 分别采用二维超声、CDFI、脉冲多普勒血流显像(PDU)及UE检查100例患者共125个乳腺病灶,并与病理结果进行比较。 结果 病理为良性者40例共65个病灶,恶性者60例共60个病灶,二维超声诊断乳腺恶性肿瘤的敏感度为80.00%(48/60),特异度为78.46%(51/65),准确率为79.20%(99/125);CDFI诊断乳腺恶性肿瘤的敏感度为78.33%(47/60),特异度为83.08%(54/65),准确率为80.80%(101/125);PDU诊断乳腺恶性肿瘤的敏感度为71.67%(43/60),特异度为58.46%(38/65),准确率为64.80%(81/125);UE诊断恶性病变的敏感度为88.33%(53/60),特异度为75.38%(49/65),准确率为81.60%(102/125)。4种检查方法比较,诊断结果差异有统计学意义(χ²=13.155,P<0.05)。 结论 UE鉴别诊断乳腺良恶性肿块的准确率高于二维超声和多普勒超声。     

BIRADS联合CEUS鉴别诊断乳腺肿瘤的良恶性

目的 探讨乳腺影像报告和数据系统(BIRADS)分类联合CEUS鉴别诊断乳腺肿瘤良恶性的价值。方法 对490例患者共524个病灶进行乳腺常规超声和CEUS检查,以病理为金标准,比较BIRADS分类及BIRADS分类联合CEUS诊断乳腺肿瘤良恶性的效能。结果 524个病灶中,良性病灶232个,恶性病灶292个。BIRADS分类诊断乳腺恶性肿瘤的特异度17.24%(40/232)、敏感度99.32%(290/292)、准确率62.98%(330/524)、阳性预测值60.17%(290/482)、阴性预测值95.24%(40/42),ROC曲线下面积0.583。BIRADS分类联合CEUS后诊断乳腺恶性肿瘤的特异度90.09%(209/232)、敏感度89.04%(260/292)、准确率89.50%(469/524)、阳性预测值91.87%(260/283)、阴性预测值86.72%(209/241),ROC曲线下面积0.896;两者曲线下面积差异有统计学意义(P<0.05)。结论 BIRADS联合CEUS有利于对乳腺肿瘤的鉴别诊断。     

体素内不相干运动双指数模型评价乳腺肿块样病变

目的 应用体素内不相干运动(IVIM)双指数模型探讨真性弥散系数(D)、与灌注相关的假性弥散系数(D^*),灌注分数(f)在诊断乳腺肿块样病变诊断中的应用价值。方法 收集经病理证实的乳腺恶性肿块48例(恶性组)、良性肿块26例(良性组)及正常体检者19名(对照组),均行常规MRI检查及多b值的弥散加权成像检查。比较3组间D值、f值、D^*值及ADC值的差异,采用ROC曲线评估各个指标对乳腺良恶性肿块样病变的诊断效能。结果 对照组、良性组及恶性组间D、f、D^*及ADC值的差异均有统计学意义(P均<0.01)。良性组D值低于对照组、且高于恶性组(P均<0.01);恶性组f值高于对照组及良性组(P均<0.01),而对照组与良性组间差异无统计学意义(P=0.14);良性组D^*值低于对照组、高于恶性组(P均<0.01);良性组ADC值低于对照组、高于恶性组(P均<0.01)。恶性组的D值显著低于ADC值(P<0.01)。分析采用各DWI参数鉴别诊断乳腺恶性肿块样变的ROC曲线,D值具有较高的诊断效能,其次依次为ADC值,f值及D^*值,曲线下面积(AUC)依次为0.95、0.90、0.87、0.75。结论 IVIM双指数模型能够真实反映乳腺肿块样病变水分子的弥散情况,尤其是D值对乳腺病变良恶性的鉴别诊断具有重要的参考意义。     

DCE-MRI联合IVIM-DWI鉴别诊断乳腺良恶性病变

目的 探讨动态增强MRI(DCE-MRI)联合体素内不相干运动DWI(IVIM-DWI)鉴别诊断乳腺良恶性病变的价值.方法 收集因乳腺病变接受DCE-MRI及IVIM-DWI检查的患者87例,经术后病理证实共93个病灶,其中良性病灶42个(良性组),恶性病灶51个(恶性组).对两组的DCE-MRI参数(病变形态、强化特点、峰值时间、最大增强斜率和TIC类型)及IVIM-DWI参数(f、D和D^*值)进行比较.采用多因素Logistic回归分析确定DCE-MRI、IVIM-DWI及二者联合鉴别诊断乳腺良恶性病变的独立影响因素.以病理诊断结果为金标准,绘制ROC曲线,并计算曲线下面积(AUC).结果 DCE-MRI、IVIM-DWI及二者联合诊断乳腺良恶性病变,纳入Logistic回归方程的独立影响因素分别为形态、TIC类型,D值,形态、TIC类型及D值.DCE-MRI、IVIM-DWI及二者联合鉴别诊断乳腺良恶性病变的敏感度、特异度、准确率分别为78.43%、71.43%、75.27%,70.59%、66.67%、68.82%,84.31%、78.57%、81.72%.3种方法的AUC分别为0.75、0.69、0.81.结论 DCE-MRI联合IVIM-DWI可提高鉴别诊断乳腺良恶性病变的效能.     

常规超声联合超声造影诊断脉络膜良恶性肿瘤

目的 观察常规超声联合超声造影（CEUS）诊断脉络膜良恶性肿瘤的价值。方法 回顾性分析60例脉络膜肿瘤患者，根据肿瘤性质分为良性组37例和恶性组23例。观察肿瘤常规超声、CEUS表现，定量分析相关参数。结果 常规超声联合CEUS诊断良恶性肿瘤的符合率为91.67%（55/60）。恶性组CEUS上升时间（RT）、达峰时间（TTP）、平均通过时间（MTT）及峰值强度（PI）均明显低于良性组（P<0.05）。结论 常规超声联合CEUS诊断脉络膜良恶性肿瘤准确率较高。     

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.