腰椎骨质密度与年龄、性别、体质参数及腹部脂肪的相关性

目的 探讨腰椎骨质密度(BMD)与年龄、性别、体质参数及腹部皮下脂肪(SAT)、内脏脂肪(VAT)的关系。方法 纳入健康志愿者或慢性腰腿痛患者111人(男56人,女55人),测量受检者身高、体质量及腰围,计算体质指数(BMI);采用定量CT(QCT)行腹部扫描,测量L3的BMD及相应层面腹部SAT与VAT含量。将男性与女性分别分为骨质疏松组、骨量减少组和骨量正常组,分别比较3组间年龄、性别、身高、体质量、BMI、腰围、SAT和VAT的差异,对BMD与存在显著性差异的指标进行相关性分析。结果 3组男性间除年龄的差异有统计学意义(P<0.05)外,身高、体质量、BMI、腰围、SAT及VAT的差异均无统计学意义(P均>0.05);男性BMD与年龄呈负相关(r=-0.680,P<0.05)。3组女性年龄、腰围及VAT的差异有统计学意义(P均<0.05),身高、体质量、BMI、SAT差异均无统计学意义(P均>0.05);女性BMD与年龄、腰围、VAT均呈负相关(r= -0.849、-0.412、-0.501,P均<0.05)。结论 男、女性腰椎BMD与年龄均呈明显负相关,与身高、体质量、BMI无明显相关性;男性腰椎BMD与腰围、SAT与VAT均无明显相关性,但女性腰椎BMD与腰围及VAT关系密切。     

MRI及1H-MRS评估针灸治疗对肥胖儿童腹部脂肪和肝内脂质含量的影响

目的 应用MRI和¹H-MRS评估针灸治疗对肥胖儿童腹部脂肪和肝内脂质含量的影响。方法 10例肥胖儿童(男7例,女3例)接受规律针灸治疗1个月,治疗前、后分别测量体质量、体质量指数(BMI)、腰围、臀围、腰臀比值(WHR)、腹部脂肪体积(应用MRI)及肝内脂质含量(应用¹H-MRS)。结果 针灸治疗后患者的BMI较治疗前减少3.50%(P=0.005)。腹腔内脂肪(VAT)体积、腹部总脂肪(TAT)体积及腹腔内脂肪/皮下脂肪比值(V／S)均较治疗前减少(P均＜0.05)。体质量、腰围、臀围、WHR、腹部皮下脂肪(SAT)体积及肝内脂质含量(IHCL) 均较治疗前减少,但差异无统计学意义(P＞0.05)。针灸治疗前后腹部脂肪体积(SAT、VAT)与人体测量参数(体质量、BMI、腰围及臀围)显著相关,而肝内脂质含量(IHCL)与人体测量参数及腹部脂肪体积等指标之间均无相关性。结论 针灸治疗可以显著减少肥胖儿童的BMI及腹部脂肪体积,特别是腹腔内脂肪体积。     

CT测量儿童正常肾皮质厚度

目的 通过测量分析儿童正常肾脏CT图像,探讨不同年龄段儿童肾皮质厚度的CT测量值的参考范围,为判断儿童肾脏形态异常提供对照标准。方法 连续选取接受腹部CT增强扫描检查的无肾脏疾病、无服用肾脏损害药物史的儿童204名,按年龄分为5组:婴儿期、幼儿期、学龄前期、学龄期、青春期,测量每侧肾脏肾门层面皮质、实质的厚度和肾脏径线长度,并进行统计分析。结果 各年龄组肾皮质厚度分别为(0.41±0.09)cm、(0.48±0.09)cm、(0.54±0.12)cm、(0.65±0.13)cm、(0.76±0.18)cm,两两组间差异均有统计学意义(P均＜0.05)。肾皮质厚度与年龄呈正相关(右侧:r=0.65,左侧:r=0.65,P均＜0.05),肾皮质与肾实质厚度之比与年龄相关性最弱(右侧:r=0.19,左侧: r=0.16,P均＜0.05)。结论 肾皮质厚度随年龄增加,肾皮质与肾实质厚度之比则随年龄变化不明显,可作为监测儿童部分肾脏疾病发展、转归的重要CT解剖依据。     

正常人肝脏3.0T磁共振弹性成像

目的 探讨我国正常成人肝脏磁共振弹性值测量的参考范围,分析弹性值与性别、年龄及体质量指数(BMI)的关系。 方法 对64名健康志愿者按年龄、性别、BMI分组,应用3.0T磁共振弹性成像(MRE)测量肝弹性值,统计分析肝弹性值与年龄、BMI的相关性,评价不同年龄、BMI及性别的组间差异。 结果 我国正常成人肝弹性值范围为1.83~3.02 kPa,平均(2.37±0.28)kPa。肝弹性值与年龄、BMI均无相关性(r=0.20、0.02,P均>0.05)。男性平均肝弹性值略高于女性(U=309.00,P=0.01),不同年龄组、BMI组间肝弹性值的差异无统计学意义(χ²=3.31、2.16,P>0.05)。 结论 定量研究我国正常成人肝弹性值可为MRE的临床应用提供依据和指导。     

应用AHP技术测量颈动脉内-中膜厚度

目的 探讨一种可以准确、方便地测量颈动脉内-中膜厚度(CIMT)的方法,评估其临床应用价值。 方法 应用超声动脉健康评估(AHP)软件自动测量238名健康人的颈总动脉、窦部和颈内动脉的内-中膜厚度和血管年龄(VA),同时手动测量颈总动脉的内-中膜厚度,并根据颈动脉上述三个部位和不同年龄组分别进行分析。 结果 不同部位的CIMT不同(窦部>颈总动脉>颈内动脉,P0.001)。年龄大于60岁组的CIMT明显大于其他组(P0.05)。随着CIMT的增厚,VA增大(r=0.951,P0.001)。VA随着年龄增大而增大(r=0.646,P0.001),但小于实际年龄(P0.001)。自动测量值明显小于手动测量值(P0.001)。 结论 AHP技术能方便准确地测量CIMT,具有应用于临床评估动脉粥样硬化的潜力。     

复发-缓解型多发性硬化患者双侧视放射扩散张量成像

目的 应用扩散张量成像(DTI)技术探讨复发-缓解型多发性硬化(RRMS)患者视力损伤与双侧视放射白质纤维束损伤的相关性。方法 选取视力损伤的RRMS患者(患者组)及年龄与性别相匹配的健康志愿者(对照组)各25例行DTI检查,分别测量双侧视放射的FA值及MD值,采用扩展残疾状态量表(EDSS)对患者进行评分。分析患者组与对照组组内及组间两侧视放射的FA值及MD值差异,以及与EDSS评分的相关性。结果 ①对照组及患者组组内双侧视放射FA值(t=0.41,P=0.68;t=0.09,P=0.92)及MD值(t=0.72,P=0.48;t=0.20,P=0.84)差异均无统计学意义;患者组左右侧视放射FA值(t=8.29,P<0.01;t=8.42,P<0.01)均较对照组下降,MD值(t=7.17,P<0.01;t=6.58,P<0.01)均高于对照组;②左右侧视放射FA值(r=-0.24,P=0.30;r=-0.13,P=0.58)及MD值(r=0.16,P=0.50;r=0.31,P=0.19)与EDSS评分无明显相关性。结论 RRMS患者视力受损与双侧视放射的白质纤维束损害具有一定的关系。     

磁敏感加权成像中脑定量测量在帕金森病中的初步应用

目的 探讨SWI对帕金森病(PD)的临床诊断价值。方法 将20例帕金森病患者分为早期PD组(n=13)和中晚期PD组(n=7),另选取14名性别、年龄与之匹配的健康志愿者为正常对照组。采用3.0T MR系统对各组中脑核团进行SWI,分别测量各核团相位值、宽度和中脑直径,计算宽度与中脑直径的比值(宽度/中脑直径),同时对PD患者进行Hoehn & Yahr分级,并对测量结果进行比较和相关性分析。结果 不同时期PD患者黑质致密带(SNc)相位值较正常人明显下降(P<0.01),中晚期PD组SNc、黑质网状带(SNr)相位值较早期PD组显著下降(P<0.01、P<0.05);早期PD组、中晚期PD组SNc宽度较正常对照组缩小(P<0.05、P<0.01),中晚期PD组SNc、SNr宽度较早期PD组明显缩小(P<0.01);中晚期PD组SNc宽度/中脑直径较正常对照组、早期PD组降低(P<0.01)。PD患者SNc、SNr相位值与Hoehn & Yahr分级呈显著负相关(r=－0.602,P<0.01;r=－0.445,P<0.05),SNc、SNr宽度与Hoehn & Yahr分级呈显著负相关(r=－0.828,P<0.01;r=－0.667,P<0.01)。PD患者SNc相位值与其宽度、宽度/中脑直径呈正相关(r=0.590,P<0.01;r=0.445,P<0.05),SNr相位值与其宽度呈正相关(r=0.493,P<0.05)。结论 应用SWI测量中脑核团相位值、宽度以及中脑核团宽度/中脑直径比值对评估PD具有临床诊断价值。     

健康国人嗅球体积MRI测值及其与年龄和嗅觉功能的相关性

目的 探讨MRI测量嗅球(OB)体积的可行性,观察健康国人OB体积随年龄增长的演变规律和与嗅觉功能的相关性。方法 随机选择103名右利手健康志愿者,采用1.5T临床型MR系统行全脑扫描,在冠状位以手绘法测量OB体积。采用Sniffin' Sticks方法检测嗅觉功能,包括嗅觉阈值、嗅觉辨别和嗅觉识别,计算嗅觉总评分(TDI)。结果 男性左、右侧OB体积平均值分别为(88.66±29.36)cm³和(92.54±30.63)cm³,女性左、右侧OB体积平均为(74.84±19.34)cm³和(72.63±20.71)cm³;男性和女性两侧OB体积差异均有统计学意义(P均<0.05)。左、右侧OB体积与年龄均呈负相关(左侧:r=-0.24,P=0.02;右侧:r=-0.28,P=0.01)。左、右侧OB体积分别与同侧TDI评分呈正相关(左侧:r=0.21,P=0.03;右侧:r=0.22, P=0.02);右侧THR和ID评分与同侧OB体积也具有相关性(THR:r=0.19,P=0.04;ID:r=0.19,P=0.04)。结论 采用1.5T临床型MR仪可清晰显示和准确测量OB体积;国人OB体积随年龄增大而逐渐减小,并与相应嗅觉功能具有相关性。     

应用分形维数定量分析MSCT肺动脉树形态学改变

目的 应用分形维数(FD)定量分析多层螺旋CT肺动脉树的形态学改变。方法 对31例患者进行增强螺旋CT扫描和经胸超声心动图检查,根据病变分为肺动脉高压组(PH组,14例)和无肺动脉高压组(无PH组,17例)。应用后处理软件形成肺动脉树,以Image J软件计算肺动脉树的投影面积及分形维数(FD);比较两组FD、肺动脉树投影面积和肺动脉压力(PAP),分析三者的相互关系。结果 PH组FD、图像投影面积和PAP均显著高于无PH组。肺动脉树的FD值与PAP、FD与图像投影面积,PAP与图像投影面积均存在正相关(r=0.82,P<0.05;r=0.49,P<0.05;r=0.65,P<0.05)。结论 FD能定量评价整个肺动脉的形态学改变,或可作为定量描述整个肺动脉形态学的重要指标之一。     

老年女性髋部脆性骨折患者的Singh指数分析

目的 探讨Singh指数在老年女性髋部脆性骨折患者骨密度评估中的应用价值。方法 将216例老年女性髋部脆性骨折患者按年龄分为4组,60~70岁组53例,71~80岁组83例,81~90岁组68例,>90岁组12例。行髋部X线摄影,评估患者健侧Singh指数,并将Singh指数≤Ⅳ级作为骨质疏松诊断标准。分析2名诊断医师间隔1个月前后两次评估Singh指数分级的一致性;比较各年龄组患者身高、体质量及体质量指数(BMI)及Singh指数的差异;并评价髋部Singh指数与患者年龄、BMI的相关性。结果 2名医师评估Singh指数分级的观察者内Kappa值分别为0.631、0.615,观察者间Kappa值分别为0.622、0.598。应用Singh指数诊断骨质疏松的总体检出率为89.35%(193/216)。各年龄组患者身高、体质量及BMI差异均无统计学意义(P均>0.05),Singh指数差异有统计学意义(H=56.077,P<0.001)。Singh指数与患者年龄呈负相关(r=－0.656,P<0.001),与BMI无相关性(r=－0.008,P=0.902)。结论 X线平片Singh指数虽然相对经济、简便且较为实用,但重复性较低,不能完全反映老年女性脆性骨折患者骨密度情况。     

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.     

手转胎头术失败的原因与分娩结局临床分析

目的 探讨手转胎头术失败的原因与分娩结局.方法 选择2008年1月至2010年12月于我院住院分娩的持续性枕横位、枕后位产妇198例,根据行手转胎头术后结果分为成功组126例、失败组72例.比较两组分娩结局,对比分析失败原因.结果 失败组胎儿体质量≥3500 g的发生率[76.4％(55/72)]明显高于成功组[31.7％(40/126)],差异有统计学意义(x2=30.177,P=0.001)、失败组宫缩乏力发生率[58.3％(42/72)]高于成功组[38.1％ (48/126)],差异有统计学意义(x2=7.569,P=0.006)、失败组骨盆临界或轻度狭窄发生率[38.9％ (28/72)]高于成功组[23.8％(30/126)],差异有统计学意义(x2 =5.030,P=0.002)、失败组手转胎头时机不当(宫口开大＜6 cm、胎头位于坐骨棘上及宫口开大8～10 cm、胎头位于坐骨棘下≥2 cm)发生率[61.1％(44/72)]高于成功组[38.9％(49/126)],差异有统计学意义(x2=9.084,P=0.003).失败组母儿并发症(产后出血、产褥病率、胎儿窘迫、新生儿窒息)发生率高于成功组(x2 =9.586,P=0.002、x2=9.334,P=0.002、x2=5.910,P=0.015、x2=5.240,P=0.022)、失败组剖宫产发生率[72.2％(52/72)]明显高于成功组[34.1 ％(43/126),x2=26.641,P=0.001)].结论 手转胎头术能使难产变顺产,降低剖宫产率,减少母儿并发症,但须积极预防、处理导致手转胎头术失败的原因,对矫正失败后继续矫正及试产应慎重.