低旋设计散光软镜临床配戴结果研究

目的评估低旋（Lo-Torque）设计散光软镜的临床效果。方法103名近视散光自愿者分别配戴A、B镜片各两周。对配戴的临床表现进行客观和主觉评价,采用双盲法。结果①镜片稳定性A镜片旋转范围≤5°为82%,B镜片为52%。②镜片在眼中状态移动度优良者,A镜片为91%,B镜片为95%;中心定位优良者,A镜片为87%,B镜片为77%。③舒适度评价A镜片优良者为85.5%,B镜片为80.2%。结论低旋设计特征的散光软镜更符合人眼的生理特征,可以提高视觉质量,增加配戴舒适度。     

The Seidel nail revisited- an evaluation of recent design change

This study evaluated a recent design change of the distal locking mechanism of the Seidel nail. The distal expansion bolt has been modified to incorporate a swagged rotating collar. The torque requirement for distal locking was measured for the original and new bolt design using a composite bone humeral model. Ten of each screw type were tested. The torque requirement for distal locking was less in the original bolt design. However the torque transmission is smoother in the new bolt design making appreciation of adequate locking more reliable.     

The reliability of isokinetic testing of the ankle joint and a heel-raise test for endurance

The aim of the present study was to investigate the reliability of different methods used for isokinetic testing of calf muscle strength and endurance. The detailed evaluation of test-retest reliability serves the purpose of establishing reliable research tools when evaluating patients who have sustained an Achilles tendon rupture. The test-retest reliability of isokinetic measurements at the ankle for eccentric and concentric muscle action was calculated in ten healthy male volunteers using intra-class correlation (ICC) and coefficient of variation (CV). Three different positions were compared at the angular velocities of 30°/s and 180°/s for right and left ankles. The ICC for plantar flexion was 0.37–0.95, whilst it was 0.00–0.96 for dorsiflexion. The corresponding CVs were 4.0–19.9 and 2.4–19.8 respectively. The test-retest reliability of standardised heel-raises, Achilles tendon width, calf circumference and ankle range of motion revealed ICC values of 0.71–0.98 and CVs of 0.67–19.1. The test-retest interval was 5 to 7 days. We conclude that all three positions studied for the isokinetic evaluation of calf muscle function are equally reliable concerning plantar flexion at the ankle joint. The same level of reliability was also found in the evaluation of the standing heel-raise test and the isokinetic dorsiflexion test, except for dorsiflexion in the supine position. The reliability of the investigated methods was only fair despite the use of a detailed and standardised test protocol.     

Bilateral eccentric and concentric torque of quadriceps and hamstring muscles in females and males

Summary This study assessed maximum eccentric (ECC) and concentric (CON) torque of quadriceps (QUAD) and hamstring (HAM) muscle groups in healthy females (n=13) and males (n=27). Peak torques (PT) of bilateral muscle actions were recorded at constant angular velocities of 0.52, 1.57 and 2.61 rad·s⁻¹. The QUAD_con and HAM_con PT decreased (p<0.05) with increasing angular velocity. The QUAD_ecc and HAM_ecc PT increased (p<0.05) in females, whereas QUAD_ecc PT decreased (p<0.05) and HAM_ecc PT showed no change in males. In general, ECC PT was higher (p<0.05) than CON PT and QUAD PT was higher (p<0.05) than HAM PT, for any given angular velocity. Males displayed higher (p<0.05) PT than females but when PT were adjusted for body mass the sex differences in QUAD_con and HAM_con were reduced (p<0.05), whereas the differences in QUAD_ecc and HAM_ecc were abolished. The CON and ECC PT were, on average, 60% and 41% greater, respectively, in males than in females. The corresponding differences, when adjusted for body mass, were 23% and 8%. ECC:CON PT for QUAD were higher (p<0.05) in females than in males. CON and ECC HAM:QUAD PT ratio increased (p<0.05), as a function of velocity. This study suggests, that bilateral ECC PT is higher than CON PT and CON HAM:QUAD PT ratio is higher than ECC HAM:QUAD PT ratio. Moreover, females and males display different ECC torque-velocity patterns, whereas CON torquevelocity patterns are similar and females possess greater QUAD_ecc PT relative to QUAD_con PT than males.     

Upgrading wet granulation monitoring from hand squeeze test to mixing torque rheometry

With over 50 years of research in granulation technology, however more research is required to elucidate this widely applicable technology. Wetting phenomena could influence redistribution of individual ingredients within a granule according their solubility and also could affect the drying processes. Binder selection for a particular system is quite often empirical and dependent on the skills and experience of the formulator. Hand squeeze test was and still the main way for determination of wet granulation end point, but it is subjected to individual variation. It depends mainly on operator experience, so it is not possible to be validated. Literature reveals a variety of advanced monitoring techniques following up different wet massing stages. Torque measurement has been proved to be the most reliable control method as its tight relation to mass resistance. Many reports showed successful applications of mixing torque rheometer (MTR) for monitoring the wet massing procedure and scale up in addition to some preformulation applications. MTR as a new approach allows formulators to select a liquid addition range where the granule growth behavior is more predictable.     

Effect of low-intensity pulsed ultrasound on orthodontically induced root resorption caused by torque: A prospective,double-blind,controlled clinical trial

Objectives:To evaluate the effects of low-intensity pulsed ultrasound (LIPUS) on orthodontically induced tooth root resorption caused by torque in human subjects.Materials and Methods:Ten healthy patients (12–35 years of age) who required extraction of all first premolars as a part of their routine orthodontic treatment were recruited. A 15° twist was applied in the arch wire using 0.019 × 0.025-inch TMA in a 0.022-inch bracket system (Synergy R) that produced a buccal root torque of approximately 5 N/mm at the bracket level. Using a split mouth design, randomization, and blinding, one side of the arch received LIPUS for 20 minutes per day for 4 weeks at an incident intensity of 30 mW/cm² of the transducers’ surface area. The other side served as a self-control, which received a sham transducer. After 4 weeks, all first premolars were extracted and micro–computed tomographic analysis was performed on these extracted teeth. A linear mixed-model statistical analysis was used.Results:LIPUS-treated teeth showed significantly less total volume of resorption lacunae compared to control teeth by a mean difference of (0.54 ± 0.09 mm³) (P < .001) and percentage of root resorption by a mean difference of (0.33 ± 0.05 mm³) (P < .001). In addition, significantly fewer resorption lacunae were found on all root surfaces in the LIPUS group compared to the control except in the instance of the distal surface.Limitations:This study was performed on limited number of cases during a 4-week period.Conclusions:LIPUS minimizes root resorption when applied during torque tooth movement over a 4-week period.     

Tip-Edge矫治器转矩力学性能的三维有限元分析

运用有限元法建立上颌前牙区带弓丝的Tip-Edge托槽三维有限元模型,研究Tip-Edge托槽不同倾斜度时转矩力学性能。用Pro/E Wildfire5.0软件建立不同倾斜度上中切牙Tip-Edge托槽及不同材质弓丝模型,装配模型并导入MSC.Marc.Mentat2005R3软件中模拟转矩加载,收集力矩值,绘制曲线图。结果表明:(1)上中切牙托槽向远中倾斜0°时,其转矩最大力矩值为22.37 Nmm;托槽倾斜25°时,其转矩最大力矩值为8.93 Nmm;(2)当托槽倾斜度相同时,不锈钢弓丝最大转矩力矩值为β-钛丝的2倍。随着托槽远中倾斜度的减小,其表达的最大转矩力矩值逐渐增大,转矩性能提高,其转矩性能主要由托槽两中央嵴间的水平距离和垂直距离决定。预置转矩表达时,托槽两侧的弓丝应力分布随着托槽远中倾斜度的减小变得不对称,这主要是由托槽两中央嵴间的水平距离决定。     

Association Between TT Virus Infection and Cirrhosis in Liver Transplant Patients

Background:

Cirrhosis is one of the most severe liver complications, with multiple etiologies. The torque teno virus (TTV), also known as transfusion transmitted virus, which has a high incidence in the world population, is one of the possible increasing risk factors in patients with idiopathic fulminant hepatitis and cryptogenic cirrhosis.

Objectives:

The aim of this study was to evaluate solitary and co-infection with TTV, in patients with cryptogenic and determined cause of cirrhosis.

Patients and Methods:

In this cross-sectional study, 200 liver transplant patients were consecutively recruited between years 2007 and 2011. Patients were classified, based on recognition of the etiology of cirrhosis to determined (n = 81) and cryptogenic (n = 119) patient groups. The existence of TTV infection was analyzed, using a semi-nested polymerase chain reaction method. The presence of hepatitis B virus (HBV) infective markers, including HBV DNA, hepatitis B surface antigen (HBsAg), hepatitis B e antigen (HBeAg), hepatitis B core antibody (HBcAb), and hepatitis B e antibody (HBeAb), was evaluated using qualitative polymerase chain reaction and enzyme linked immunosorbent assay protocols, respectively.

Results:

The TTV infection was found in 37 of 200 (18.5%) and 53 of 200 (26.5%) plasma and tissue samples of studied liver transplanted patients, respectively. The TTV genomic DNA was found in 32 (26.9%) and 28 (23.5%) of 119 liver tissue and plasma samples of transplanted patients with cryptogenic cirrhosis, respectively. The genomic DNA of TTV was also diagnosed in 21 (25.9%) and nine (11.1%) of the 81 liver tissue and plasma samples of patients with determined cirrhosis, respectively. Significant associations were found between TTV infection with HBV molecular and immunologic infective markers, in liver transplanted patients, with determined and cryptogenic cirrhosis.

Conclusions:

The diagnosis of the high frequency of solitary TTV and co-infection with HBV, in both liver transplanted patients with cryptogenic and determined cirrhosis, emphasized on the importance of TTV infection in the development of cirrhosis, especially in the cases of cryptogenic ones, prompting for further studies the confirm this agent in the etiology of determined cirrhosis.     

Low-Frequency Pulsed Current Versus Kilohertz-Frequency Alternating Current: A Scoping Literature Review

Objectives

To compare the effectiveness of low-frequency pulsed current versus kilohertz-frequency alternating current in terms of evoked force, discomfort level, current intensity, and muscle fatigability; to discuss the physiological mechanisms of each neuromuscular electrical stimulation type; and to determine if kilohertz-frequency alternating current is better than low-frequency pulsed current for clinical treatment.

螺旋CT测量的颌骨密度与扭矩的关系在牙种植术中的应用

目的：探讨应用螺旋CT测得骨密度值与种植体旋入扭矩的对应关系在牙种植术中的作用。方法：对20例患者,共42个上颌后牙受植区,进行种植受区颌骨CT扫描,通过软件测得种植区骨密度值用Hounsfield Units（HU）表示并记录,然后记录种植术中旋入种植体所用扭矩,数据用spss10.0软件进行统计学分析。结果：HU=141.45±36.60,其对应旋入扭矩≤0.25N.m;HU=295.73±75.11,其对应旋入扭矩为介于0.25N.m和0.35N.m之间;HU=530.93±116.48,其对应旋入扭矩≥0.35N.m。二者间相关系数为0.902,呈正相关。结论：术前测量颌骨CT值对提高种植体的初期稳定性有重要参考价值。