多层螺旋CT评价先天性单冠状动脉畸形

目的 探讨16层螺旋CT（MSCT）冠状动脉造影诊断先天性单冠状动脉畸形的价值。资料与方法 回顾性分析4例先天性单冠状动脉患者的MSCT和常规X线冠状动脉造影（CCA）资料。对比两者在显示和诊断此病中的差异。仿真内镜技术用于评价异位开口及其与邻近正常冠状动脉开口的关系,多平面重建、曲面多平面重建、最大密度投影、容积成像等重建方法则用于评价变异冠状动脉的行径及其与邻近大血管的关系。结果 4例患者变异的冠状动脉全部为MSCT造影所显示并明确诊断。MSCT显示3例患者的左主干起源于右冠状动脉的近段,其中1例在CCA中左主干仅近段局部显影,未能明确诊断,另2例左冠状动脉虽显影,但较淡。1例右冠状动脉起源于左主干的末端,CCA则误为起源于回旋支。MSCT显示2例异常开口冠状动脉的近段狭窄,3支异常冠状动脉穿过主动脉根部和肺动脉或右室流出道的间隙,1支绕主动脉根部后方走行,而CCA均不能明确诊断。结论 MSCT显示先天性单冠状动脉明显优于CCA,凡疑及冠状动脉变异的患者,可首选非创伤性的MSCT冠状动脉造影检查。     

Botulinum toxin A in the hemiplegia upper limb: a double-blind trial

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.     

酸处理对光敏玻璃离子边缘封闭性的影响

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。     

Compression of radiological images with 512, 1,024, and 2,048 matrices

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%.     

Nitroglycerin-induced headache is not dependent on histamine release: support for a direct nociceptive action of nitric oxide

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.     

Plastic-adherent progenitor cells in mobilized peripheral blood progenitor cell collections

The use of peripheral blood progenitor cells (PBPC) to reconstitute hematopoiesis after high-dose chemoradiotherapy is now commonplace in the treatment of malignancies. Attempts to characterize these cells have concentrated primarily on their phenotype and their content of clonogenic colony-forming cells (CFC). We have used a plastic-adherent delta (P delta) assay system to evaluate the quantity and quality of more primitive cells in addition to the conventional measurements of CFC and CD34-positive cells. The leukapheresis products from 20 patients mobilized using cyclophosphamide (Cy) and granulocyte colony- stimulating factor (G-CSF) were examined for progenitor cell content. The mean number of mononuclear cells (MNC), colony-forming units- granulocyte/macrophage (CFU-GM), and CD34-positive cells from two leukaphereses per patients were 7.9 x 10(8)/kg, 47.3 x 10(4)/kg, and 10.5 x 10(6)/kg, respectively. The mean number of P delta progenitors was 9.3 x 10(4)/kg. Limiting dilution analyses showed the frequency of P delta progenitors in PBPC to be between 1 and 5.3 per 10(5) MNC and that each P delta progenitor has the proliferative capability to generate an overall mean of 4.5 CFU-GM. Of the 20 patients, 16 underwent autografting with PBPC alone. Fifteen patients engrafted neutrophils and platelets within 16 days. One patient had delayed engraftment associated with inadequate etoposide clearance. Statistical analysis showed a strong correlation between numbers of CFU-GM and CD34 positivity. The numbers of plastic-adherent P delta progenitor cells did not correlate with CFU-GM or CD34-positive cells. We conclude that the plastic-adherent P delta progenitor cell assay is capable of measuring primitive hematopoietic cells and that it may be useful for the investigation of primitive progenitors in PBPC harvests.     

空气喷磨对预防性树脂充填微渗漏的影响

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。