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81.
In a randomised, double-blind study, the effects of intramuscular injection of botulinum toxin type A (BtA) into the upper limb were compared with those of normal saline solution in 14 patients with cerebral palsy; their mean age was 9 years. Range of movement and function were assessed before injection and at 2 and 12 weeks after injection. BtA injection significantly increased maximum active elbow and thumb extension and significantly reduced tone at wrist and elbow. The hand grasp-and-release score improved, representing a modest functional change, but fine motor function, assessed by the ability to pick up coins, did not improve and in some cases deteriorated temporarily. The most notable subjective change was the cosmetic benefit of reduced involuntary elbow flexion. The tone-reducing effect of BtA was clinically detectable in comparison with the placebo and patients and parents perceived the change as beneficial. The median of changes in the treatment group was small but the range Was large, suggesting that BtA can be useful in selected patients.  相似文献   
82.
研究酸蚀对光敏玻璃离子的微渗漏影响。方法:采用侵害性窝沟封闭技术处理36颗人离休磨牙,并随机分成3组,每组12颗,第Ⅰ组为对照组,用37%磷酸酸蚀后,用低粘稠度复合树脂Liquicoat封闭窝沟裂隙。第Ⅱ组处理同第Ⅰ组,用低粘稠度光敏玻璃离子PrimaFlow封闭窝沟裂隙。第Ⅲ组与第Ⅱ组不同之处,对牙釉质不进行酸蚀。每组半数牙齿进行热循环处理(5~55℃,2500周)。所有标本用0.5%亚甲基蓝着色,在立体显微镜下观察微渗漏等级。结果:微渗漏第Ⅰ组与第Ⅱ组相似(P>0.05)。第Ⅰ、Ⅱ组较第Ⅲ组小(P<0.001)。复合树脂经热循环处理后微渗漏有增加(P<0.01),而光敏玻璃离子粘固粉经热循环处理后微渗漏没有增加(P>0.05)。结论:光敏玻璃离子结合酸蚀技术能减少微渗漏。  相似文献   
83.
Lo  SC; Huang  HK 《Radiology》1986,161(2):519-525
A comprehensive study was performed using the full-frame bit-allocation compression technique on 78 radiological images, including digitized radiographs, computed radiographs, and computed tomography images. Each radiograph was digitized to 2,048 X 2,048 X 10, 1,024 X 1,024 X 10, and 512 X 512 X 10 matrices, respectively, with a laser scanner. Five compression ratios were used to compress each image, and reconstructed images from each compressed data set were obtained. Altogether, the authors studied 842 images, including the original and compressed-reconstructed images and the images obtained from the difference between the original and the reconstructed images. The results indicate that acceptable compression ratios for 2,048, 1,024, and 512 matrices are 25:1, 20:1, and 10:1, respectively, based on a mean-square error of 0.02%.  相似文献   
84.
The molecular mechanisms of migraine pain have not yet been clarified. Monoamine and the peptide neurotransmitters involved in neurogenic inflammation do not cause significant head pain. Our previous studies of glyceryl trinitrate (GTN) and histamine-induced headaches have suggested that nitric oxide (NO) is the causative molecule in migraine pain. We furthermore suggest that substances capable of inducing experimental vascular headache do so via a common mediator which is NO. Finally, it is suggested that drugs exert their antimigraine activity by inhibiting NO or subsequent steps in the cascade of intracellular reactions triggered by NO. These novel observations change current views on vascular headache mechanisms and the importance of NO as an initiator of the migraine attacks dictates new approaches to the pharmacological treatment of migraine and other vascular headaches.  相似文献   
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88.
Multislice spiral CT(MSCT)has recently e-volved as a modalityfor non-invasive coronaryi ma-ging.16-slice MSCT allows excellent distal coro-nary coverage with higer temporal and spatial reso-lution.It can be usedto detect stenosis of coronaryartery with a diameter≥1.5cm[1,2].We investi-gated a group of coronary MSCT angiography(MSCTA)results,with those of selective X-raycoronary angiography(SCA)serving as the refer-ence standard.1MATERIALS AND METHODS1.1PatientsBetween July20…  相似文献   
89.
空气喷磨对预防性树脂充填微渗漏的影响   总被引:1,自引:1,他引:0  
目的 :体外评价空气喷磨、酸蚀和两者结合对预防性树脂充填微渗漏的影响。方法 :对照组 (I,n =12 )对人离体磨牙常规预防性树脂充填。其余组分别用 5 0 μ(Ⅱ,Ⅲ)和 27μ(Ⅳ ,Ⅴ)氧化铝喷磨 ,其中两组 (Ⅳ ,Ⅴ)酸蚀 30s。每组一半牙齿进行热循环处理 (5~ 5 5℃ ,2500周 )后 ,用亚甲基蓝溶液着色。结果 :不论结合酸蚀与否 ,用 5 0 μ氧化铝喷磨 ,均与对照组不存在显著性差异 (p >0.05)。但喷磨后酸蚀比单纯喷磨能显著地减少微渗漏 (p<0.05)。 5 0 μ较 27μ氧化铝微粒显著地减少微渗漏(p <0.05)。结论 :空气喷磨结合酸蚀能显著地减少预防性树脂充填的微渗漏。  相似文献   
90.
cIMPACT‐NOW (the Consortium to Inform Molecular and Practical Approaches to CNS Tumor Taxonomy) was established to evaluate and make practical recommendations on recent advances in the field of CNS tumor classification, particularly in light of the rapid progress in molecular insights into these neoplasms. For Round 2 of its deliberations, cIMPACT‐NOW Working Committee 3 was reconstituted and convened in Utrecht, The Netherlands, for a meeting designed to review putative new CNS tumor types in advance of any future World Health Organization meeting on CNS tumor classification. In preparatory activities for the meeting and at the actual meeting, a list of possible entities was assembled and each type and subtype debated. Working Committee 3 recommended that a substantial number of newly recognized types and subtypes should be considered for inclusion in future CNS tumor classifications. In addition, the group endorsed a number of principles—relating to classification categories, approaches to classification, nomenclature, and grading—that the group hopes will also inform the future classification of CNS neoplasms.  相似文献   
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