左心室旋转运动研究进展

左心室旋转运动由左心室收缩期扭转运动和舒张期解旋运动构成.左心室收缩期心内膜与心外膜下心肌纤维向相反方向运动,导致左心室扭转,进而引起左心室收缩射血.舒张期左心室心肌迅速弹性回缩释放扭转时储存的弹性势能,引起左心室早期快速充盈.任何影响心肌状态的生理或病理变化均可使左心室旋转运动发生改变.心肌收缩及松弛程度、前后负荷、心内膜及心外膜下心肌纤维收缩的平衡和心肌纤维的排列方向共同决定和影响左心室扭转运动;左心室扭转峰值、左心室弹性回缩力及心肌松弛特性决定左心室解旋运动,其他相关因素亦可影响左心室旋转运动,如运动、年龄等.该文就左心室旋转运动相关研究进展进行综述,以促进其在临床的推广应用.     

改良第一跖骨基底旋转截骨治疗重度拇外翻

目的：探讨第一跖骨基底旋转截骨,联合植骨治疗拇外翻的疗效。方法对于23例拇外翻患者（34足）行第一跖骨基底旋转截骨,并联合植骨矫正拇外翻畸形,通过对手术前后AOFOS评分,评价该术式疗效。结果对全部患者均随访8~24个月（平均18个月）,拇外翻角（HVA）由术前（45.0±3.5）°减小到（11.0±3.6）°（t=61.5, P〈0.05）,第一、二跖骨间角（IMA）由术前（20.1±3.5）°减小到（9.0±1.0）°（t=25.0, P〈0.05）。AOFAS评分由术前（38.0±6.0）矫正至术后（90.0±2.0）（t=58.0, P〈0.05）结论第一跖骨基底旋转截骨联合植骨治疗重度拇外翻对治疗重度拇外翻有显著疗效。     

Striatal A2 receptor regulates apomorphine-induced turning in rats with unilateral dopamine denervation

The effect of the purine agonist N-ethylcarboxamido-adenosine (NECA) on apomorphine-induced rotation was investigated in rats with unilateral 6-hydroxydopamine lesions of the nigrostriatal pathway. Intrastriatal administration of NECA on the denervated side caused a dose-dependent inhibition of contralateral rotation. This inhibition was prevented by prior intrastriatal injection of theophylline. The adenosine A₁ receptor antagonist 8-cyclopentyltheophylline was ineffective at concentrations which block this receptor, but effective in preventing the action of NECA at concentrations which block the adenosine A₂ receptor. In the absence of apomorphine, NECA had no effect on behaviour. It is concluded that A₂ receptor activation counteracts apomorphine effects in the striatum. Since the A₂ receptor may be localized to striatal cholinergic neurones, the possible role of these neurones in purine-induced behaviours is discussed.     

Reversed rotation of the midgut in adults – a case report

Intestinal obstruction is a common surgical emergency. It is often due to adhesions; however, when the patient is young and has a virgin abdomen, we have to consider uncommon causes. We present a rare case of reversed rotation of the midgut as a cause for intestinal obstruction.     

Similar effects ofd-amphetamine and cocaine on extracellular dopamine levels in medial prefrontal cortex of rats

The effects of behaviorally equivalent doses of D-amphetamine and cocaine on extracellular dopamine (DA) levels in the left and right medial prefrontal cortex (PFC) were investigated using microdialysis in anesthetized rats. The two drugs increased extracellular DA levels to a similar extent and, in each case, there was a tendency for the effects to be greater in the left than in the right side of the brain. For both drugs, there was a strong negative correlation between basal levels and the magnitude of the drug response; this relationship, while important to consider when comparing one drug to another, could not account for the left-right differences in drug effects. Contrary to some previous reports, the present data indicate that D-amphetamine and cocaine do not differ substantially with regard to their effects on dopamine neurotransmission in the PFC.     

Early results of a rotational flap to treat chronic anal fissures

Background Treatment of anal fissures has changed dramatically in the past decade. Only a few fail to respond to medical therapy. Sphincterotomy and anal dilatation have fallen out of favour due to the risk of incontinence. Island flaps have been proposed to address this, but 60–70% of flap donor sites break down with complications. We proposed that using a rotational flap would overcome this problem.Methods Twenty-one patients (14 women,7 men) with chronic anal fissures were treated with rotation flap from perianal skin. The median age was 43 (range 21–76) years. All patients had failed chemical sphincterotomy and showed no signs of improvement following at least a 3-month course of topical GTN 0.2% ointment.Results The median hospital stay was 2 days. Seventeen patients had complete resolution of symptoms. Only one patient continued to have severe pain. Two developed a recurrent fissure. One patient had a combined fistula–fissure complex at diagnosis and suffered from a breakdown of the flap and donor site. Another patient had had haemorrhoidectomy and an advancement flap in the past. He developed problems with the donor site, which was successfully managed conservatively. One patient had persistent mild pain after surgery, but the cause could not be found. None of the patients suffered continence defects after surgery.Conclusion Use of a rotational flap is a simple, safe and successful treatment for anal fissures. Donor site problems are minimised using this approach. It should be a treatment of choice when surgery is required for chronic anal fissures, particularly in patients in whom there is a risk of incontinence.These are the results of the initial ten cases presented as a poster at the annual meeting of The Association of Coloproctology of Great Britain and Ireland, July 2003. The abstract was published in Colorectal Disease, 5 [Suppl 1]:73, July 2003. Poster presentation at the British Society of Gastroenterology meeting, Glasgow, March 2004. The abstract was published in Gut, A66 [Suppl 3:53, April 2004. Oral presentation at the Association of Surgeons of Great Britain and Ireland meeting, 28–30th April 2004. The abstract was published in Br J Surg 91(1), May 2004.     

基于曲线拟合法与算术平均法计算双探头SPECT旋转中心漂移值的比较

目的 研究基于曲线拟合法与算术平均法计算单光子发射计算机断层成像（SPECT）设备探头旋转中心漂移值的差异性。方法 选取3个厂家的9台SPECT设备,每台设备都分别用曲线拟合法与算术平均法计算探头旋转中心漂移值,比较两种计算方法计算结果的差异性。同时将探头按照厂家分组,根据各厂家规定的合格值,将两种计算方法的结果与厂家自带软件计算的结果进行比较。结果 一共13个探头的13组数据中,两种计算方法计算结果之间数据差异无统计学意义（P>0.05）,两种计算方法计算结果分别与厂家计算结果之间比较,数据差异均无统计学意义（P>0.05）。两种计算方法计算结果分别与厂家计算结果相比,通过性均一致。结论 两种方法均能为旋转中心漂移的检测提供参考。     

Correcting rotational deformity following femoral nailing

Introduction

The incidence of rotational malalignment after femoral nailing has been reported to be at least 20%. If the deformity is recognised early, it can be corrected by changing the distal locking screw and rotating the bone prior to fracture union. It is common practice to use the same distal locking screw of the nail if this surgery is performed, however, there is a risk of the new drill hole “cutting out” into the old screw hole. The degree of rotational deformity that needs to be corrected to use the same distal locking hole without cut out of the screw has not been defined.

Method

Ten femora, five from cadavera and five synthetic (“Synbone”), were stabilised in a vice and then fitted with one distal transverse screw. The screw was then removed and a second distal transverse screw was inserted at the same level after variable amounts of rotation. The bone bridge between the drill holes was then measured and any cut out was noted.

Results

Both of the femora cut out when rotated 10°, and one when rotated 15°. The size of the bone bridge between drill holes in femora rotated by 20° was 3 mm. This bone bridge was increased to 4 mm when the femora were rotated by 25°, and 8 and 9 mm when rotated by 30°.

Conclusion

The amount of rotational deformity that needs to be corrected in order to use the same distal locking hole in a femoral nail is significant. In our study, this equates to a correction of at least 25°, but this is not a definitive value in practice. Particular attention must be paid to the location and size of the distal locking screw when correcting malrotation after femoral nailing, to ensure an adequate bone bridge between the two holes.     

Calculation of rotational deformity in pediatric supracondylar humerus fractures

Objective Supracondylar humerus fractures (SCHF) are common in the pediatric population. Cubitus varus deformity (CVD) is the most common long-term complication of SCHFs and may lead to elbow instability and deficits in throwing or extension. Distal fragment malrotation in the axial plane disposes to fragment tilt and CVD; however, no simple method of assessing fracture malrotation exists. This study tested a mathematical method of measuring axial plane malrotation in SCHFs based on plain radiographs. Design A pediatric SCHF model was made, and x-rays were taken at known intervals of rotation. Five independent, blinded observers measured these films. Calculated rotation for each data set was compared to the known rotation. The identical protocol was performed for an aluminum phantom. Results The reliability and agreement of the rotation values were good for both models. Conclusions This method is a reliable, accurate, and cost-effective means of calculating SCHF distal fragment malrotation and warrants clinical application. This study was conducted at the NYU Hospital for Joint Diseases. None of the authors received financial support for this study.