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31.
Zoï Kapoula Maria Pia Bucci Frederic Jurion Julie Ayoun Farzaneh Afkhami Dominique Brémond-Gignac 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2006,245(7):931-936
Aim There is a controversy as to whether dyslexic children present visuo-motor disabilities such as vergence and accommodative
problems assessed with orthoptic tests. The purpose of this study is to re-examine this issue in a large population of children.
Methods Extensive orthoptic evaluation was made in 57 dyslexic and 46 non-dyslexic (“normal”) age-matched children. Convergence and
divergence capacities were evaluated at two distances (30 cm and 400 cm).
Results Binocular vision measured with stereo-acuity tests was normal in dyslexics. In contrast, the near point of convergence was
significantly more remote in dyslexics; most importantly, divergence at both far and near distance was significantly more
reduced in dyslexics (median value 4 pD and 10 pD, respectively, at far and near) than in “normals” (median value 6 pD and
12 pD, at far and near).
Conclusion The existence of the divergence deficit at far distance indicates the presence of deficit of divergence per se, independently
from convergence and accommodation relaxation. This result is novel and corroborated by physiological studies indicating distinct
control of convergence and divergence, both at the cortical and subcortical premotor level. We conclude that vergence deficits
are frequently present in dyslexics, and that dyslexics should be re-educated; training should address distinctively convergence
and divergence subsystems. 相似文献
32.
多级图像对比度放大技术在膝关节摄影中的应用 总被引:1,自引:0,他引:1
目的:分析评价膝关节摄影中多级图像对比度放大技术(MUSICA)参数设定的成像效果,为实际临床应用提供理论指导。方法:随机抽取膝关节侧位软拷贝图像70例,以骨皮质、骨小梁、肌间隙、髌上囊、皮下脂肪为比对目标,由三位观察者对其显示情况进行分析,并对结果进行统计分析。结果:MUSICA处于较小值(0~2)时,适合于软组织显示,但图像锐利度欠缺;处于较高值时(4~6)适合于观察骨皮质、小梁等细节信息,但较多地出现伪影,共25例;处于2~4时整体影像对比度适中,如实反映人体密度结构。结论:作图像处理时应将MUSICA为2~4设定为常规,实际应用通常情况下可以选择该处理方法,但应根据具体要求适当调整MUSICA参数值。 相似文献
33.
应用电子计算机计算血液流变学的正常值及分析 总被引:4,自引:0,他引:4
为评价血流粘滞诸因素生理与病理的异常,对济南地区338例正常人血液流变学的各项指标进行了检测,统计了血液流变学各项指标的总平均及男女的平均值和正常范围,并计算了血液流变学各项指标间的相关系数。 相似文献
34.
Lars von Knorring Béla G. L. Almay Jan Häggendal Folke Johansson Lars Oreland Lennart Wetterberg 《European archives of psychiatry and clinical neuroscience》1986,236(3):131-138
Summary The aim of the present study was to investigate the discriminative power of a series of variables (including determination of depressive symptomatology by means of a visual analogue scale, determination of personality traits by means of the Karolinska Scales of Personality, determination of monoamine metabolites in CSF, platelet MAO activities, serum cortisol before and after dexamethasone suppression and urinary melatonin) in differentiating (a) chronic pain patients from healthy subjects, and (b) patients with idiopathic pain syndromes from patients with neurogenic pain syndromes. Separately each of the measures gave a significant but often low contribution to the discrimination, while a combination of several measures gave a complete discrimination both between healthy subjects and patients with chronic pain syndromes and between patients with idiopathic and neurogenic pain syndromes, respectively.Supported in part by grants from the Swedish Medical Research Council (grants no. 3371, 4145 and 5740) and by a grant from Stiftelsen Söderström-Königska Sjukhemmet 相似文献
35.
36.
CT的分叶征表现在肺内孤立结节影像诊断中的价值 总被引:7,自引:0,他引:7
目的探讨CT的分叶征表现在肺内孤立结节影像诊断的价值以及CT多平面重组(MPR)对此征检出的意义。方法观察病理证实的周围型小肺癌137例及良性肺内结节45例,将结节的边缘分为4型。对28例肺癌、22例良性结节行MPR,考察其显示分叶征的作用。引入可能性比值(likelihood ratios,LR)以量化良恶性病变在形态学上存在重叠的表现。结果Ⅰ型边缘结节对良性病变的特异性为83.3%(20/24),敏感性为44.4%(20/45)。Ⅳ型边缘结节对周围型小肺癌的特异性为97.6%(83/85),敏感性为60.7%(83/137)。表明Ⅰ型边缘是良性病变的特点;而Ⅳ型边缘是恶性病变的特征。Ⅳ型边缘的结节恶性病变在MPR重组图像上的检出率为64.3%(18/28),与横断面扫描差异有统计学意义(P〈0.01)。结论分叶征对肺内孤立结节的诊断有价值,MPR配合横断面薄层图像有助于提高该征的检出率。 相似文献
37.
The present study investigated relationships between global QOL perceptions and well-being dimensions. Especially our goal was to evaluate the impact of generally recognised four broad dimensions of QOL (physical, functional, social and emotional well-being) on global QOL perceptions, additionally person's satisfaction with life achievements and economical situation were measured as well as social demographic variables. The subjects were a representative sample of Finns (n = 4613, from 25 to 65 years) of the FINRISK-97 study. Correlation coefficients and models of hierarchical regression indicated that physical, functional and social well-being as well as sociodemographic factors and satisfaction with life achievements are important factors of global QOL perceptions both among males and females. However percentages of variances explained with these measures were only moderately high, ranging from 1 to 10%. After measures of emotional well-being were entered into the models of hierarchical analyses of regression, variances explained grew dramatically over 20%. The results of the study indicated that global QOL judgements are likely to be based on current emotional state. 相似文献
38.
Robert M. Levy Roman Saikovsky Evgeniya Shmidt Alexander Khokhlov Bruce P. Burnett 《Nutrition Research》2009
Flavocoxid (Limbrel), a proprietary mixture of flavonoid molecules (baicalin and catechin), was tested against a traditional nonsteroidal anti-inflammatory drug, naproxen, for the management of the signs and symptoms of moderate osteoarthritis (OA) in humans. Discomfort and global disease activity were used as the primary end points, and safety assessments were also taken for both treatments as a secondary endpoint. In this double-blind study, 103 subjects were randomly assigned to receive either flavocoxid [500 mg twice daily (BID)] or naproxen (500 mg BID) in a 1-month onset of action trial. Outcome measures included the short Western Ontario and McMaster University Osteoarthritis Index, subject Visual Analogue Scale for discomfort and global response, and investigator Visual Analogue Scale for global response and fecal occult blood. Both flavocoxid and naproxen showed significant reduction in the signs and symptoms of knee OA (P ≤ .001). There were no statistically detectable differences between the flavocoxid and naproxen groups with respect to any of the outcome variables. Similarly, there were no statistically detectable differences between the groups with respect to any adverse event, although there was a trend toward a higher incidence of edema and nonspecific musculoskeletal discomfort in the naproxen group. In this short-term pilot study, flavocoxid was as effective as naproxen in controlling the signs and symptoms of OA of the knee and would present a safe and effective option for those individuals on traditional nonsteroidal anti-inflammatory drugs or cyclooxygenase-2 inhibitors. A low incidence of adverse events was reported for both groups. 相似文献
39.
英语阅读障碍儿童词汇命名加工特征的研究 总被引:1,自引:1,他引:0
目的研究英语阅读障碍儿童操作英语词汇的相关能力 ,探索英语阅读障碍的表现特点与矫治的手段。方法英语真、假词命名实验 ,观察 3 4名阅读障碍儿童和 3 4名对照组儿童的实验结果。结果 ( 1)障碍组右视野在真、假词的命名时间上与对照组存在显著差异 ;( 2 )障碍组在真词和假词上的命名错误率均大于正常组 ,假词命名的错误率大幅增加。 ( 3 )障碍组右视野的真词命名时间明显长于左视野 ,假词命名的错误率也明显大于左视野。结论英语阅读障碍的儿童显示出了操作英语语音能力的欠缺以及左测大脑半球活动水平不足的倾向。 相似文献
40.
Ashish Raj Honglei Zhang Martin R Prince Yi Wang Ramin Zabih 《Magnetic resonance in medicine》2006,55(3):649-658
Time-resolved contrast enhanced magnetic resonance angiography (MRA) may suffer from involuntary patient motion. It is noted that while MR signal change associated with motion is large in magnitude and has smooth phase variation in k-phase, signal change associated with vascular enhancement is small in magnitude and has rapid phase variation in k-space. Based upon this observation, a novel projection onto convex sets (POCS) algorithm is developed as an automatic iterative method to remove motion artifacts. The presented POCS algorithm consists of high-pass phase filtering and convex projections in both k-space and image space. Without input of detailed motion knowledge, motion effects are filtered out, while vasculature information is preserved. The proposed method can be effective for a large class of nonrigid motions, including through-plane motion. The algorithm is stable and converges quickly, usually within five iterations. A double-blind evaluation on a set of clinical MRA cases shows that a completely unsupervised version of the algorithm produces significantly better rank scores (P=0.038) when compared to angiograms produced manually by an experienced radiologist. 相似文献