Crime displacement in digital drug markets

Background Crackdowns on urban sites with concentrated criminal activity are sometimes followed by geographical relocation of crime. Is this also the case in cyberspace, where illegal websites and online networks can be wiped clean, but also quickly rebuilt and replaced on new servers and URLs?Methods I address this question in three steps. First, I measure MDMA trade in a large digital market for drugs, before and after the arrest of a leading MDMA seller in the same market. Second, I count the number of available digital drug markets and vendor shops in the period February 2014–June 2018, to see if websites closed by police were replaced by new ones. Third, I track the digital movement and trading activities of individual drug sellers, before and after law enforcement shut down two large markets.Results After police arrested a leading MDMA seller, other MDMA sellers filled most – but not all – of the gap. A major law enforcement crackdown reduced the number of available markets, but new ones were created, and market counts eventually surpassed the previous peak. When law enforcement shut down two big markets, many of the sellers relocated to other e-commerce sites and continued high-earning operations there.Conclusion Arrests and market closures redirect digital drug trade to other sellers and markets. Hot spot policing in cyberspace might produce temporary results, but is arguably ineffective in the long run, as actors use information and communication technology’s unique capacities to reorganize.     

基于疼痛特点的腰椎间盘突出症个体化疾病诊断

疼痛是所有腰腿痛病例共同的临床症状,但疼痛的病因、病理、部位（范围或区域）、强度、性质、演变情况和影响因素等具有一定的特点与规律。这些个体化差异既是特定疾病临床诊断的首要依据,也是鉴别诊断的重要参考。在明确疾病诊断与鉴别诊断的基础上,腰椎间盘突出症病例尚须进一步区别典型与非典型、单纯与复合、普通与特殊等个体化疾病特征,在此基础上才能确定个体化疾病治疗方案。     

在β地中海贫血着床前遗传学诊断中应用多重置换扩增进行预处理的临床分析

目的分析应用多重置换扩增技术(multiple displacement amplification,MDA)进行全基因组扩增的预处理是否影响β地中海贫血着床前遗传学诊断(preimplantation genetic diagnosis,PGD)的准确效能。方法回顾性地分析2009年1月至2013年6月,因双方均为β地中海贫血携带者而行PGD治疗的周期资料,其中34个周期采用多重巢式聚合酶链反应(PCR)结合反向斑点杂交技术对单细胞进行诊断,另有38个周期行MDA进行全基因组扩增的预处理后,再结合反向斑点杂交技术进行诊断。结果两组患者在年龄、获卵数等实验室指标上无统计学差异。MDA组未检出(扩增失败)率为9.79%,低于行巢式PCR组的15.24%,而杂合子率46.33%则略高,但两种方法在诊断结果上并无统计学差异。结论应用MDA技术进行全基因组的预扩增可有效增加检测模板,实现多位点及多种疾病的诊断,而且不影响β地中海贫血地贫基因的诊断效能。     

带线锚钉与钢板内固定治疗肱骨大结节骨折的优劣分析

背景:手术治疗肱骨大结节骨折目前普及切开复位钢板螺钉固定,但存在着一些不足。目的:比较切开复位带线锚钉与切开复位钢板内固定治疗肱骨大结节骨折的疗效。方法:回顾性分析2016年1月至2018年12月苏州大学附属第一医院收治的肱骨大结节骨折33例患者的资料,根据内固定方式分为锚钉组(n=7)和钢板组(n=26),分别行切开复位带线锚钉和切开复位钢板螺钉内固定。统计比较2组患者手术时间、切口长度、术中失血量、术后骨折块再移位距离及术后1个月、3个月、末次随访肩关节功能Constant-Murle评分,并记录2组内固定的不良反应情况。结果与结论:①锚钉组手术时间(73.1±10.5)min短于钢板组(98.2±11.9)min,切口长度(7.3±1.1)cm小于钢板组(14.9±1.7)cm,术中失血量(45.0±7.1)m L小于钢板组(141.0±25.9)mL,差异均有显著性意义(P<0.05);②锚钉组术后骨折块再移位距离(3.0±1.8)mm大于钢板组(1.1±2.3)mm,差异有显著性意义(P<0.05);③术后1,3个月及末次随访时,2组之间Constant-Murle评分比较,差异均无显著性意义(P>0.05);④提示与切开复位钢板内固定相比,切开复位带线锚钉内固定治疗肱骨大结节骨折具有手术时间短、创伤小的优势。     

Ruptured disc after arthroscopic repositioning in the temporomandibular joint: a retrospective magnetic resonance imaging study

Our aim was to explore the incidence of rupture after arthroscopic repositioning of the disc of the temporomandibular joint (TMJ) by reviewing magnetic resonance images (MRI) of the TMJ taken before and after operation, and to investigate correlations retrospectively. We studied 247 patients with anterior disc displacement of the TMJ, and categorised them into 3 groups based on the postoperative MRI. The first group comprised those whose disc ruptured after repositioning, the second those who had a possible rupture of the disc after repositioning, and the third had no rupture of the disc after repositioning. Age, sex, duration of symptoms, maximum incisal mouth opening, whether the anterior disc displacement was unilateral or bilateral, and the Wilkes stage, were included in the analysis. The incidence of rupture (5/247) was 2%. Weak points at the intermediate zone of the disc were found in 4 of the 5 joints. The patients whose discs ruptured were significantly younger than the other 2 groups (p = 0.001). There was no statistically significant difference in preoperative duration of symptoms and mouth opening among the groups. The proportions of unilateral and bilateral disc displacement (p = 0.047) and Wilkes stage (p = 0.027) differed among the 3 groups. The Wilkes stages was significantly more advanced in the ruptured group than in the other 2 groups (p = 0.027) with 4/5 being bilateral. The weak point in the intermediate zone of the disc on MRI could be a sign of rupture. Teenagers and young adults with anterior disc displacement without reduction, particularly those in whom it is bilateral, are at a higher risk of a rupture after repositioning of the disc by arthroscopy.     

Could different TMJ disc positions observed in MRI cause different sounds? Analysis on a group of subjects with ADD with reduction: a pilot study

Aims:

Magnetic resonance imaging (MRI) is the method of choice for examining soft-tissue pathology of the temporomandibular joint (TMJ). MRI shows a high spatial resolution with accuracy for the identification of internal derangement. Tasaki developed a classification system for disc displacement in the TMJ, identifying eight different types of disc displacements in addition to the superior disc position. This study aims to test the ability of electrosonography (ESG) in discriminating different kinds of disc displacement according to the disc position criteria proposed, comparing the ESG results with those obtained by MRI.

Methodology:

Twenty-seven patients were selected from an initial group of 50 patients with articular disc displacement, selected by means of clinical examinations, according to the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) and who had both MRI and ESG studies performed. For each patient and for each peak in ESG, both in the opening and closing movements, three different parts of the sound were analyzed. The frequency (Hz) and the mean amplitude (μV) of the sounds were calculated in the three analyzed windows. Afterwards, gathering the data for the Tasaki’s classes and dividing opening and closing sounds, the number of peaks was calculated, as well as average and standard deviations for both the Hz and µV.

Results:

The peak frequency shows significant differences between different disc positions during the first and second third of the opening phase and during the first third of the closing phase. The peak amplitude shows significant differences between different disc positions during all of the opening and closing phases.

Conclusions:

Although limited by sample size, the present study shows the presence of different sounds with different Hzs and μVs associated with different disc positions that were recorded with ESG.     

Clarifying the nomenclature of intervertebral disc degeneration and displacement: from bench to bedside

As a significant determinant of low back pain, intervertebral disc degeneration (IDD) has attracted more and more attention of both investigators and physicians. Disc herniation, termed as intervertebral disc displacement, is amongst the most prevalent spinal diseases closely linked with IDD. Due to the same origins and similar pathophysiology, the ambiguity regarding the similarity and difference of IDD and intervertebral disc displacement thus remains. The aim of this study was to clarify the nomenclature of IDD and disc herniation in terms of molecular etiology, pathophysiology, nature history and clinical outcomes. Collectively, IDD is a type of multifaceted, progressive spinal disease with or without clinical symptoms as back pain, characterized by extracellular matrix and the integrity of NP and AF lost, fissures formation. Disc herniation (termed as intervertebral disc displacement) is a type of spinal disease based on IDD or not, with local pain and/or sciatica due to mechanical compression and autoimmune cascades upon the corresponding nerve roots. Clarifying the nomenclature of intervertebral disc degeneration and displacement has important implications both for investigators and for physicians.     

Displacement of the full body of a dental implant into the sinus space without membrane perforation and subsequent osseointegration: a case report

An increasing number of studies have investigated the use of osteotome sinus floor elevation (OSFE) with simultaneous implant placement for maxillary sinus floor residual bone height (RBH) <4 mm. Many studies have reported good clinical results, but very few have reported complications related to this procedure. Here, the case of a 50-year-old female patient with an RBH in the left upper posterior region of 1–4 mm, who underwent OSFE with simultaneous placement of three Bicon short® implants, is described. One of the implants was found to be displaced during the second-stage surgery. The displaced implant was removed using piezosurgery, OSFE with simultaneous implant placement was repeated, and the missing tooth was reconstructed 6 months later. This case suggests that OSFE with simultaneous implant placement is feasible for severely atrophic maxillary sinus floor, but carries a risk of implant displacement.     

人工椎间盘置换术后腰椎稳定性的实验研究

目的：探讨人工椎间盘置换对腰椎稳定性的影响：方法：10具新鲜尸体腰椎标本,分别按椎间盘完整、椎间盘切除、椎间盘置换和椎间盘置换加后纵韧带局部切断4种状态进行前屈、后伸以及左、右侧屈4种生理运动的生物力学测试,按2,4,6,8,10Nm分级加载,记录各分级载荷下的线性位移与角位移．计算平均顺应系数。结果：椎间盘切除标本的各项指标与完整标本比较差异均有统计学意义（P〈0．05,P〈0．01）;椎间盘置换标本前屈与后伸最大载荷时的线性位移与角位移、平均顺应系数与椎间盘切除标本比较差异均有统计学意义（P〈0．05,P〈0．01）;后伸运动线性移位和角位移的平均顺应系数及最大载荷角位移与完整标本比较差异均有统计学意义（P〈0．05）;椎间盘置换加后纵韧带局部切断标本前屈、后伸和左、右侧屈运动时的线性位移、角位移和平均顺应系数与椎间盘置换后纵韧带完整标本比较差异均没有统计学意义（P〉0．05）。结论：腰椎间盘置换术能保留腰椎的稳定性,必要时局部切断后纵韧带对人工椎间盘置换后腰椎的稳定性无不良影响。     

脑脊液置换加鞘内注射地塞米松治疗高血压性脑出血破入脑室临床研究

目的 观察腰椎穿刺（腰穿）脑脊液置换加鞘内注射地塞米松治疗高血压性脑出血破入脑室的临床价值。方法 设治疗组30例和对照组28例。两组入院后均给予常规药物治疗;治疗组在24h内施行第一次腰穿脑脊液置换术,并予鞘内注射地塞米松,每天1次,共3～5次。结果 治疗组总有效率93．3％,对照组总有效率78．6％,经统计学处理差异有极度显著性（P〈0．01）。结论 采用脑脊液置换加鞘内注射地塞米松治疗高血压性脑出血破入脑室疗效好,且简便安全易操作。