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81.
甲襞微循环观测辅助诊断的初步研究胡金麟*田牛*刘凤英*宋欣*李向红*规范化的甲襞、球结膜、舌、口唇、牙龈、耳廓、皮肤、子宫颈、阴茎头微循环观测方法标志着我国临床微循环的研究与应用已进入了一个新的阶段[1,2]。临床微循环观测结果的数学公式表达,促进了... 相似文献
82.
目的:本研究采用Howes法评估牙弓骨量与牙量的协调性,探讨其在正畸临床诊断与矫治设计确定拔牙与非拔牙中的应用价值。方法:选取第四军医大学口腔医学院正畸门诊患者80人,男、女拔牙与非拔牙各20例。测量牙量(TM)、双尖牙弓宽径(PMD)、双尖牙根尖基骨宽径(PMBAW)、基骨弓长度(BAL),并计算PMD/TM、PMBAW/TM、BAL/TM值,对其进行统计学处理与分析。结果:男女两组比较TM、PMD、PMBAW、BAL值有显著性差异,男性大于女性;但PMD/TM、PMBAW/TM、BAL/TM值无统计学意义;拔牙组与非拔牙组比较,PMD/TM、PMBAW/TM、BAL/TM值有显著性差异。结论:采用Howes法评估牙弓骨量与牙量对正畸临床的诊断和拔牙与非拔牙矫治设计有一定的指导意义。 相似文献
83.
目的:建立经胸小剂量多巴酚丁胺超声心动图激发试验(Dobu-UCG)评价犬冬眠心肌定量的方法学。材料和方法:成功建立冬眠心肌犬7条3~6个月后进行DoBu-UCG试验,测量Dobu-UCG后的心肌梗死区运动幅度(wall motion amplitude of area with myocardium infarction,MMI)和非梗死区心内膜运动幅度(wall mo-tion amplititude of areas with non myocardium infarction,MNMI)的比值(MMI/MNMI),以及试验后MMI/MNMI与试验前MMI/MNMI的差值(D值);并与实验后测量组织切片的冬眠心肌面积(the area oftotal alive myocardium,ATAM)和梗死区总面积(the area of total infarction myocardium,ATIM)的比值(ATAM/ATIM)进行比较。结果:Dobu-UCG激发试验后MMI/MNMI比值、D值分别与ATAM/ATIM进行对比分析,显示两者均高度相关(r=0.83~0.90,P分别为<0.05和<0.001)。结论:测量Dobu-UCG激发试验后MMI/MNMI比值,以及试验后、前MMI/MNMI差值(D)是定量梗死区内冬眠心肌的较好方法。 相似文献
84.
85.
Ralph Beneke Jörg Neuerburg Klaus Bohndorf 《European journal of applied physiology》1991,63(6):424-429
Summary Muscle cross-section areas were measured by magnetic resonance imaging (MRI) in the thigh of a human cadaver,. the results being compared with those obtained by photography of corresponding anatomic macroslices. A close correlation was found between MRI and photographic evaluation, differences between the methods ranging from nil to 9.5%, depending on the scan position and the muscle groups. In vivo MRI measurements were performed on 12 female and 16 male students, the objectivity, the test-retest reliability and the variability of the MRI measurements being studied by fixing the scan position either manually or by coronary scan. The latter method appeared to be more objective and reliable. The coefficients of variation for muscle cross-section areas measured by MRI were in the range of those for the planimetry of given cross-section areas. Allowing for differentiation between several small muscle bundles in a given area, MRI proved to be a suitable method to quantify muscle cross-sections for intra- and interindividual analysis of muscle size. 相似文献
86.
动脉顺应性又称动脉弹性,反映血管内皮功能。已成为预测心血管疾病的重要危险因素。无创测量动脉弹性的方法在临床上已有一定程度的应用。各种方法具有其各自适用范围及局限性。多种干预手段可以影响动脉弹性。合理测量及维持正常的动脉弹性可延缓多种心血管疾病的发生及发展。 相似文献
87.
作者提出了一种膈神经放电信号的计算机分析方法,用以克服该信号手工分析时存在的问题。计算机通过对膈神经放电信号的采集、数字整流与滤波等处理后,可得到放电的包络图,从中能自动测量一些重要参数。动物实验证实程序能较好地执行这些功能。统计学分析表明,人工测量结果与计算机测量结果之间无显著性差异。 相似文献
88.
目的:研究CT仿真结肠内窥镜(CT Virtual Colonoscopy,CTVC)的使用价值,应用方法及镜下表现。方法:使用Hispeed FX/i扫描机,扫描层厚3~5mm,螺距1~2,重叠重建率50%~67%。利用Navigator Smooth软件对容积扫描数据进行三维重建,获得仿真结肠内窥镜的影像,并与纤维肠镜和/或手术所见对照分析,全部病例经病理证实。结果:通过选择不同的观察方位,角度和阈值,CTVC能清楚显示靶器官内正常解剖结构的立体影像和病变的部位、大小、形态及其侵犯范围。CTVC对结肠病变形态的显示与FC或/和标本显示具有良好的对应性,另外,CTVC能从闭塞和狭窄的远端观察病变。但CTVC不能显示组织的颜色变化,不能活检。结论:CTVC作为一种新的非侵袭性结肠检查方法,可以作为纤维结肠镜的有效补充手段,有较好的临床应用价值。 相似文献
89.
Maria Drangova Yudong Zhu Norbert J. Pelc 《Journal of magnetic resonance imaging : JMRI》1997,7(4):664-668
The reproducibility of myocardial motion trajectories calculated from cine phase-contrast (PC) velocity data is reduced by artifacts due to the inconsistent motion of intracardiac blood. Spatial presaturation reduces these artifacts but requires a longer sequence TR, with a potentially negative effect on trajectory accuracy and reproducibility. We investigated the effect of spatial presaturation on trajectory reproducibility. A midventricular transaxial slice was imaged in five normal volunteers. The same slice was imaged three times each with sequences using spatial presaturation or not. Because the most serious artifacts originate in the heart chambers and propagate in the phase-encoded direction, myocardial regions that were in line with the heart chambers (in the phase-encode direction) had the highest artifact level in the scans without spatial presaturation. The reproducibility of trajectories for regions placed in these areas (the anterior wall, septum and posterior wall in the transaxial scans with phase encoding in the anterior-posterior direction) improved by a factor of two when presaturation was used (P < .001). In areas that were not in line with the heart chambers (eg, the anterior aspect of the lateral wall in the transaxial scans), the effect of presaturation was not significant. These results correlate well with the measured reduction in artifact level. The reproducibility of myocardial motion trajectories over large areas of the heart is improved to approximately 1 mm when presaturation is used. Therefore, use of presaturation is recommended for myocardial motion studies using cine PC velocity data. 相似文献
90.
We examined two recently developed measures of positive automatic thought, the Positive Automatic Thoughts Questionnaire (ATQ-P)
and the Automatic Thoughts Questionnaire—Revised (ATQ-RP). Internal consistency, concurrent validity, and convergent and discriminant
validity were addressed. Two hundred one undergraduates completed self-report measures of positive automatic thoughts, negative
automatic thoughts, depressive symptoms, anxiety symptoms, and positive affectivity. The ATQ-P and ATQ-RP both showed high
internal consistency, strong negative associations with depressive symptoms, specificity to depressive symptoms rather than
anxiety symptoms, an average state-of-mind (SOM) ratio in the positive dialogue range, and a stronger relation with each other
than with a measure of positive affectivity. The only notable difference between the measures was a significantly lower mean
score (correcting for number of items) on the ATQ-RP.
This paper is based on a thesis completed by the first author, under the supervision of the second author, in partial fulfillment
of the requirements for the Master of Arts degree at American University. We are grateful to thesis committee members Lorah
Dorn and Jim Gray for feedback on this material. 相似文献