Systematic assessment and evaluation of sliding interleaved ky (SLINKY) acquisition for 3D MRA

In comparison with the conventional three-dimensional multiple overlapped thin slab acquisition (MOTSA) for magnetic resonance angiography (MRA), we have developed a novel sliding interleaved k_y (SLINKY) acquisition technique, which can eliminate the slab boundary artifact (SBA) or venetian blind artifact without any a priori knowledge of blood flow. This work addresses the systematic assessment and evaluation of the SLINKY technique and verifies the advantages of SLINKY in the following several aspects: (a) scan time efficiency; (b) signal-to-noise ratio (SNR), and signal-difference-to-noise ratio (SDNR); (c) sensitivity to flow velocity range; (d) sensitivity to flow direction; (e) signal loss in slow/reversal flow regions; and (f) reconstruction efficiency and feasibility. Both phantom and in vivo experiments verify the clinical significance of the technique. The new MRA images acquired with this imaging technique in 31 volunteer/patient examinations show highly reliable mapping of vascular morphology without the SBA and reduction of signal voids in complex/slow flow regions.     

食管裂孔疝内镜诊断探讨

６０例经Ｘ线检查确诊为滑动型食管裂孔疝病人作胃镜观察食管－胃连接部的改变。另３４例为对照组。经统计学处理，作者认为可作为食管裂孔疝的内镜诊断标准。     

A case of 46, XY DSD presenting as a crossed ectopic gonad with a contralateral sliding inguinal hernia

A three-month-old boy was referred to our facility for the treatment of a right impalpable testis, left inguinal hernia, and penoscrotal hypospadias with asymmetric external genitalia. The left gonad was palpated in the left scrotum. The chromosomal study revealed a normal male 46, XY karyotype. Operative findings showed that the right streak gonad, uterus, and fallopian tubes were in the wall of the left hernia sac, forming a sliding hernia. Laparoscopy confirmed that the right gonadal vessels had crossed to the left internal inguinal ring. Herniorrhaphy was done and the right streak gonad, uterus, and fallopian tubes were excised. An exploration of the left gonad revealed an ovotestis. The ovary was removed, and a left testicular biopsy was simultaneously performed. A one-stage hypospadias repair using Koyanagi procedure was also performed. The pathological findings showed an ovarian stroma in the right gonad and left ovary. Only Sertoli cells were detected in the biopsied specimen from the left testis.     

Dual lag screw cephalomedullary nail versus the classic sliding hip screw for the stabilization of intertrochanteric fractures. A prospective randomized study

This study is a randomized prospective study comparing two fracture fixation implants, the extramedullary sliding hip screw (SHS) and the dual lag screw cephalomedullary nail, in the treatment of intertrochanteric femoral fractures in the elderly. One hundred and sixty-five patients with low-energy intertrochanteric fractures, classified as AO/OTA 31A, were prospectively included during a 2-year period (2005–2006). Patients were randomized into two groups: group A included 79 hip fractures managed with sliding hip screws and group B included 86 fractures treated with cephalomedullary nails. Delay to surgery, duration of surgery, time of fluoroscopy, total hospital stay, implant-related complications, transfusion requirements, re-operation details, functional recovery, and mortality were recorded. The mean follow-up was 36 months (24–56 months). The mean surgical time was statistically significantly shorter and fluoroscopy time longer for the group B. No intraoperative femoral shaft fractures occurred. There was no statistically significant difference in the functional recovery score, reoperation, and mortality rates between the 2 groups. A new type of complication, the so-called Z-effect phenomenon, was noticed in the cephalomedullary nail group. There are no statistically significant differences between the two techniques in terms of type and rate of complications, functional outcome, reoperation and mortality rates when comparing the SHS and the cephalomedullary nail for low-energy AO/OTA 31A intertrochanteric fractures. Our data do not support recommendations for the use of one implant over the other.     

The treatment of trochanteric fractures using a sliding screw-plate

Summary The authors report a retrospective study of 307 trochanteric fractures treated with a sliding screw-plate (trochanteric hip screw, THS) between January 1989 and December 1994. Mechanical failure was uncommon (3.6%); cutting-out of the screw was the main complication. The revision rate was also low (4%); the 12 cases included 5 total hip replacememts and 2 sliding-screw replacements. Whatever the fracture type, the main factors preventing mechanical failure were the quality of the fracture reduction, the good positioning of the screw in the femoral head and the range of postoperative sliding of the screw. Of those patients who had previously lived at home, 20% were able to return there directly while 73% were admitted to a rehabilitation center, old people's home or medical unit. At the date of the last follow-up, 72% of patients who initially lived at home had returned there but 24% were still dependent. These results confirm the effectiveness of the device, provided the initial surgical indications and technical operating conditons are satisfactory.     

Inguinal hernia in infants and children in China

Inguinal hernia repair for children and infants is one of the most common operations done as day surgery in China. In a series of 11,272 cases in Beijing Children's Hospital, 10,101 (89.6%) were performed as day cases. Of 1,171 hospitalized patients, 633 (54%) had incarcerated hernias. The standard procedures of day-surgery repair include a small transverse incision at the external ring, high ligation of the sac, and a constriction stitch on the external ring. Many reports involving thousands of day-surgery herniorrhaphies performed by community surgeons with no mortality or remarkable complications have been presented in the last 10 years in the Chinese literature. Most surgeons prefer to perform the repair in children between the ages of 6 months and 6 years, while some neonatal surgeons have done many in the first few days after birth. The problems of recurrence, latent contralateral hernia, sliding hernia, congenital hernia, incarceration, and common complications are discussed. Correspondence to: J.-z. Zhang     

The Epiperiosteal, percutaneous plate osteosynthesis. A minimally invasive technique under the aspect of biological osteosynthesis

Summary Conservation of bone perfusion, protection of the soft tissue envelope and reduction of systemic stress by strengthening the host defence mechanism are general and essential aspects of a biological osteosynthesis. The minimal invasive operating techniques with the use of technical aids and tricks form the necessary presupposition for successful bone healing with a low complication rate. For an epiperiosteal, percutaneous plate osteosynthesis, the technique using a sliding tip and a manipulation handle is demonstrated.      

Series-elastic properties of strips of smooth muscle from pig urinary bladder

The series elasticity of strips of smooth muscle from pig urinary bladder was investigated by means of a series of computerised quick-release and quick-stretch measurements with and without stimulation of the muscle, and at different shortenings and force levels. The results cannot be interpreted in terms of a discrete passive series-elastic element. They can, however, be interpreted in terms of the sliding-filaments model for contracting muscle.     

移动滑轨在椎体瘤调强放疗计划中的动态剂量扰动

目的 研究Qfix kVue治疗床移动滑轨在椎体瘤调强放射治疗(IMRT)计划中的动态剂量扰动。方法 移除EDGE直线加速器碳基绝缘滑轨,进行CT扫描并上传至治疗计划系统,重建床板和滑轨模型。依据均质模体和非均质患者CT,分别制作6和10 MV光子IMRT计划(180°、200°、220°、160°、140°),处方剂量为3 Gy/次,共10次,采用AcruosXB计算剂量。分别制作无滑轨和双侧滑轨对称移动(4~19 cm,步长1 cm)的优化计划。在优化计划中添加、移除滑轨结构,创建验证计划。对比分析验证计划和优化计划的差异,包括靶区平均剂量(D_mean)、均匀性指数(HI)、适形度指数(CI)和脊髓最大剂量(D_max)。结果 有无滑轨患者靶区HI均变差,其最大差值为2%。6 MV有滑轨时患者靶区D_mean减少(2.07±0.99)%,靶区CI值增加(4.91±3.12)%,脊髓D_max减少(1.83±1.37)%。无滑轨时患者靶区D_mean增加(2.02±0.96)%,靶区CI减少(3.07±1.31)%,脊髓D_max增加(2.03±1.44)%。移除和添加滑轨组间,靶区D_mean、CI和脊髓D_max差值差异有统计学意义(F=27.55、361.32、13.05,P<0.05)。靶区D_mean和脊髓D_max随滑轨位置变化呈倾斜的"W"减少。在滑轨＜10 cm范围内,差值出现极大值。当滑轨向外侧移动时,差值逐渐减小为0,6 MV计划中靶区D_mean和脊髓D_max变化值＞10 MV。结论 Qfix kVue治疗床滑轨位置变化对椎体瘤IMRT计划扰动不可忽略,计划制作时应予以考虑,治疗时滑轨应与计划位置保持一致。     

The sliding threshold of modification hypothesis: application to the effect of hypothyroidism or chronic psychosocial stress and nicotine on synaptic plasticity

The Bienenstock, Cooper, and Munro (BCM) theory or the sliding threshold model can be used to explain the changes in synaptic plasticity related to learning and memory, namely long-term potentiation (LTP) and depression (LTD). In this study, we applied synaptic plasticity changes induced by either chronic psychosocial stress or hypothyroidism, and their restoration by chronic nicotine treatment, to the sliding threshold model. Psychosocial stress- or hypothyroidism-induced changes in synaptic plasticity generated a shift in the sliding threshold of modification (θ_m) toward LTD. In addition, chronic nicotine treatment restored the θ_m to the normal position by normalizing psychosocial stress- or hypothyroidism-induced impairment of LTP and enhancement of LTD. The data correlate with our previous findings: a shift in the balance of kinase/phosphatase toward phosphatase during psychosocial stress or hypothyroidism, which is restored by chronic nicotine treatment.