Increased MR signal intensity secondary to chronic cervical cord compression

Summary Magnetic resonance images of 128 patients with compressive lesions of the cervical spinal canal were reviewed to determine whether a high signal intensity lesion within the spinal cord was present on T2 and proton density weighted spin echo images. Such high signal intensity was observed in 24 cases or 18.8%. The incidence was higher in herniated disk (32.4%), atlanto-axial dislocation (28.6%), and ossification of the posterior longitudinal ligament (22.7%), whereas the abnormality was found sporadically in cervical spondylosis and vertebral body tumors. The high intensity lesion on T2 weighted images was generally observed in patients with constriction or narrowing of the spinal cord. The lesion was not demonstrated on T1 weighted spin echo images. Spinal cord constriction or localized narrowing seemed to be the most important portant predisposing factor in producing such a high signal intensity. The pathophysiologic basis of such an abnormality was presumed to be myelomalacia or cord gliosis secondary to a long-standing compressive effect of the spinal cord.     

Effects of compressive loading on biomechanical properties of disc and peripheral tissue in a rat tail model

Intervertebral disc degeneration induced by mechanical compression is an important issue in spinal disorder research. In this study, the biomechanical aspect of the rat tail model was investigated. An external loading device equipped with super-elastic TiNi springs was developed to apply a precise load to the rat tail. By using this device, rat tail discs were subjected to compressive stress of 0.5 or 1.0 MPa for 2 weeks. Discs in the sham group received an attachment of the device but no loading. After the experimental period, first the intact tail with peripheral tissues (PT) such as tendon and skin and then the retrieved disc without PT were subjected to a uniaxial tension–compression test; biomechanical characteristics such as range of motion (ROM), neutral zone (NZ), and hysteresis loss (HL) were evaluated. Furthermore, the load-bearing contribution of PT in the intact tail was estimated by comparing the load–displacement curves obtained by the mechanical tests performed with and without PT. The experimental findings revealed that the continuous compressive stress induced reduction in disc thickness. The intact tail demonstrated decreases in ROM and NZ as well as increases in HL. On the other hand, the retrieved disc demonstrated increases in ROM, NZ, and HL. Further, a significant increase in the load-bearing contribution of PT was indicated. These findings suggest that the load-bearing capacity of the disc was seriously deteriorated by the application of compressive stress of 0.5 or 1.0 MPa for 2 weeks.     

经皮椎体成形术治疗骨质疏松性椎体骨折疗效观察

目的探讨经皮椎体成形术治疗骨质疏松性椎体压缩性骨折的临床疗效及应用价值。方法36例骨质疏松性压缩性骨折患者45个椎体，在C型臂X线透视下，取俯卧位，经皮穿刺，在病椎注入聚甲基丙烯酸甲酯。术前及术后3d进行疼痛视觉类比评分（VAS评分），并进行统计学分析。结果治疗后36例患者疼痛较治疗前有明显好转，VAS评分差异有统计学意义（P〈0．001）；活动能力也有不同程度改善；部分椎体的前缘和椎体中部高度有一定恢复。结论经皮椎体成形术治疗骨质疏松性椎体压缩骨折止痛效果明显，能很快改善患者的活动能力，早期下床活动。该手术属微创手术，在骨科临床有一定的应用前景。     

压缩雾化吸入普米克令舒和喘乐宁佐治喘憋性肺炎的观察及护理

目的 探讨压缩雾化吸入普米克令舒和喘乐宁治疗喘憋性肺炎的疗效。方法 将168例喘憋性肺炎患儿随机分为两组。对照组82例，治疗组86例。治疗组行压缩雾化吸入普米克令舒和喘乐宁治疗，对照组按常规超声雾化吸入治疗。结果 治疗组总有效率96．51％，对照组总有效率81．7％，两组疗效比较，差异具有显著性（P〈0.01）。结论 压缩雾化吸入普米克令舒和喘乐宁是佐治喘憋性肺炎的有效方法。     

Clinical outcomes of percutaneous vertebroplasty for selective single segment dorsolumbar vertebral compression fractures

Overview of literature

Elderly patients sustaining a trivial fall may develop vertebral compression fractures if they are predisposed to any factor that leads to decreased bone mineral density. Such patients suffer with severe pain and disability during the early healing stages. Percutaneous Vertebroplasty is mainly done to provide immediate pain relief and also believed to offer stability to the compressed vertebra by preventing further collapse.

MR成像在单椎体塌陷性病变鉴别诊断中的应用

目的描述骨折或骨转移所致单椎体塌陷性病变的MRI表现,探讨其鉴别诊断价值.方法对33例单椎体塌陷性病变行MR检查,其中29例临床证实,4例穿刺活检证实,良性13例,恶性20例,分析其MRI表现.结果与良性病变相比,恶性者常伴瘤周水肿,边界模糊,受累椎体鲜有残存骨髓影,受侵附件多呈膨胀性改变,常伴椎旁软组织影,强化欠均匀,追随观察病灶增大变多或无明显改变.结论 MRI能较好鉴别单椎体塌陷性病变的良恶性.     

静脉输液拔针后按压方法的研究

目的 探讨静脉输液拔针后局部按压的最佳方法,最大限度地保护患者的血管.方法 将620例患者随机分成2组,设为对照组和观察组各310例,分别采用交换式按压(传统按压法)和非交换式按压(小鱼际肌直接按压法)进行对比研究.结果 观察组在静脉输液拔针后疼痛、针眼出血、皮下淤血等次数均明显低于对照组,2组比较差异有统计学意义(P<0.01).结论 静脉输液拔针后采用小鱼际肌直接按压优于传统的按压法,值得临床推广.     

Ecg Compression by Modelling the Instantaneous Module/Phase of Its Dct

Recent developments in compression methods on the non-linear and non-stationary data, such as electrocardiograms (ECG), have received large attention by the time-frequency analysts. The technique presented in this paper is based on parametrical modeling the instantaneous module as well as the instantaneous phase, estimated directly from the Discrete Cosine Transform (DCT) of each ECG beat. The estimated parameters are then used to reconstruct each recorded beat. In order to evaluate the performance of our technique, data recorded from the MIT-BIH arrhythmia database are used.     

Modeling powder encapsulation in dosator-based machines: II. Experimental evaluation

A theoretical model was previously derived to predict powder encapsulation in dosator-based machines. The theoretical basis of the model was discussed earlier. In this part; the model was evaluated experimentally using two powder formulations with substantially different flow behavior. Encapsulation experiments were performed using a Zanasi encapsulation machine under two sets of experimental conditions. Model predicted outcomes such as encapsulation fill weight and plug height were compared to those experimentally obtained. Results showed a high correlation between predicted and actual outcomes demonstrating the model's success in predicting the encapsulation of both formulations. The model is a potentially useful in silico analysis tool that can be used for capsule dosage form development in accordance to quality by design (QbD) principles.     

调整氧化铝内冠轴壁聚合度对全瓷冠强度的影响

目的 探讨在全瓷冠基牙预备轴壁聚合度偏大的情况下,调整氧化铝内冠轴壁聚合度对全瓷冠抗压强度的影响.方法 将离体的上颌左中切牙制备成轴壁内聚12°的基牙预备体,并制作A、B、C组轴壁聚合度(4°、8°、12°)的氧化铝内冠.内冠上堆筑饰面瓷恢复牙冠形态,通过加载实验测试其抗压强度.结果 A组抗压强度最高,A、B组间无统计...