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1.
PurposeTo compare morphological imaging features and CT texture histogram parameters between grade 3 pancreatic neuroendocrine tumors (G3-NET) and neuroendocrine carcinomas (NEC).Materials and methodsPatients with pathologically proven G3-NET and NEC, according to the 2017 World Health Organization classification who had CT and MRI examinations between 2006-2017 were retrospectively included. CT and MRI examinations were reviewed by two radiologists in consensus and analyzed with respect to tumor size, enhancement patterns, hemorrhagic content, liver metastases and lymphadenopathies. Texture histogram analysis of tumors was performed on arterial and portal phase CT images. images. Morphological imaging features and CT texture histogram parameters of G3-NETs and NECs were compared.ResultsThirty-seven patients (21 men, 16 women; mean age, 56 ± 13 [SD] years [range: 28-82 years]) with 37 tumors (mean diameter, 60 ± 46 [SD] mm) were included (CT available for all, MRI for 16/37, 43%). Twenty-three patients (23/37; 62%) had NEC and 14 patients (14/37; 38%) had G3-NET. NECs were larger than G3-NETs (mean, 70 ± 51 [SD] mm [range: 18 - 196 mm] vs. 42 ± 24 [SD] mm [range: 8 - 94 mm], respectively; P = 0.039), with more tumor necrosis (75% vs. 33%, respectively; P = 0.030) and lower attenuation on precontrast (30 ± 4 [SD] HU [range: 25-39 HU] vs. 37 ± 6 [SD] [range: 25-45 HU], respectively; P = 0.002) and on portal venous phase CT images (75 ± 18 [SD] HU [range: 43 - 108 HU] vs. 92 ± 19 [SD] HU [range: 46 - 117 HU], respectively; P = 0.014). Hemorrhagic content on MRI was only observed in NEC (P = 0.007). The mean ADC value was lower in NEC ([1.1 ± 0.1 (SD)] × 10−3 mm2/s [range: (0.91 - 1.3) × 10−3 mm2/s] vs. [1.4 ± 0.2 (SD)] × 10−3 mm2/s [range: (1.1 - 1.6) × 10−3 mm2/s]; P = 0.005). CT histogram analysis showed that NEC were more heterogeneous on portal venous phase images (Entropy-0: 4.7 ± 0.2 [SD] [range: 4.2-5.1] vs. 4.5 ± 0.4 [SD] [range: 3.7-4.9]; P = 0.023).ConclusionPancreatic NECs are larger, more frequently hypoattenuating and more heterogeneous with hemorrhagic content than G3-NET on CT and MRI.  相似文献   
2.
Three‐dimensional (3D) printing technology, virtual reality, and augmented reality technology have been used to help surgeons to complete complex total hip arthroplasty, while their respective shortcomings limit their further application. With the development of technology, mixed reality (MR) technology has been applied to improve the success rate of complicated hip arthroplasty because of its unique advantages. We presented a case of a 59‐year‐old man with an intertrochanteric fracture in the left femur, who had received a prior left hip fusion. After admission to our hospital, a left total hip arthroplasty was performed on the patient using a combination of MR technology and 3D printing technology. Before surgery, 3D reconstruction of a certain bony landmark exposed in the surgical area was first performed. Then a veneer part was designed according to the bony landmark and connected to a reference registration landmark outside the body through a connecting rod. After that, the series of parts were made into a holistic reference registration instrument using 3D printing technology, and the patient's data for bone and surrounding tissue, along with digital 3D information of the reference registration instrument, were imported into the head‐mounted display (HMD). During the operation, the disinfected reference registration instrument was installed on the selected bony landmark, and then the automatic real‐time registration was realized by HMD through recognizing the registration landmark on the reference registration instrument, whereby the patient's virtual bone and other anatomical structures were quickly and accurately superimposed on the real body of the patient. To the best of our knowledge, this is the first report to use MR combined with 3D printing technology in total hip arthroplasty.  相似文献   
3.
Arthroscopic acromioclavicular joint excision is a commonly performed but technically demanding procedure. Incomplete excision can leave residual symptoms. We present a simple, reproducible technique ensuring satisfactory excision of the joint.  相似文献   
4.
5.
Objective: The objective of this study was to gain greater insight into individuals’ quality of life (QOL) definitions, appraisals, and adaptations following spinal cord injury (SCI).

Design: A mixed-methods design, applying the Schwartz and Sprangers response shift (RS) model. RS is a cognitive process wherein, in response to a change in health status, individuals change internal standards, values, or conceptualization of QOL

Setting: Community-dwelling participants who receive medical treatment at a major Midwestern medical system and nearby Veterans’ Affairs hospital.

Participants: A purposive sample of participants with SCI (N?=?40) completed semi-structured interviews and accompanying quantitative measures.

Interventions: Not applicable.

Outcome Measures: Qualitative data were analyzed using content analysis to identify themes. Analysis of variance were performed to detect differences based on themes and QOL, well-being, and demographic and injury characteristics.

Results: Four RS themes were identified, capturing the range of participant perceptions of QOL. The themes ranged from complete RS, indicating active engagement in maintaining QOL, to awareness and comparisons redefining QOL, to a relative lack of RS. Average QOL ratings differed as a function of response shift themes. PROMIS Global Health, Anxiety, and Depression also differed as a function of RS themes.

Conclusion: The RS model contextualizes differences in QOL definitions, appraisals, and adaptations in a way standardized QOL measures alone do not.  相似文献   

6.
动脉栓塞对骨盆肿瘤手术疗效的影响   总被引:15,自引:2,他引:13  
[目的]探讨供血动脉栓塞对骨盆肿瘤手术疗效的影响。[方法]本组16例,脊索瘤7例,骨巨细胞瘤3例,骨转移瘤3例,骨肉瘤2例,神经纤维瘤1例。术前1d行肿瘤血管造影并用明胶海绵进行供血动脉栓塞。与对照组(结扎双侧髂内动脉骨盆肿瘤切除术)比较,观察其对术中出血量、手术时间、住院时间、术后下床时间、伤口愈合时间及术后各种功能恢复的影响。[结果]骨盆肿瘤切除术前肿瘤供血动脉栓塞与结扎双侧髂内动脉比较,除术中出血量外(P〉0.05),手术、住院、术后下床及伤口愈合时间在统计学上均有非常显著性差异(P〈0.001),而且结扎双侧髂内动脉可能对患者的性功能、排便功能等存在着不良的影响。[结论]肿瘤供血动脉栓塞骨盆肿瘤切除术可大大缩短手术、住院、术后下床、伤口愈合时间,且能更好地保护盆腔内外各组织器官的血运,从而避免其功能的损害。  相似文献   
7.
目的观察和评价外剥、内扎硬化注射术治疗混合痔的近期疗效.方法作者采用外剥、内扎硬化注射术治疗混和痔800例.结果近期治愈788例,治愈率98.5%,好转12例,好转率1.5%.治愈天数10~21天.结论外剥、内扎硬化注射术治疗混合痔简单实用,手术时间短,术后痛苦小,伤面愈合快,并发症少,无后遗症,复发率低,是治疗混合痔的较好方法.  相似文献   
8.
Female urinary incontinence is a common but underreported condition. Initial investigation and treatment can in most cases be undertaken without urodynamic or other detailed tests. History by the use of validated symptom and quality of life questionnaires is key to the initial investigation. Initial treatment includes pelvic floor muscle training (PFMT) regardless of the type of incontinence; lifestyle interventions and bladder retraining, anticholinergics and serotonin/noradrenaline reuptake inhibitors (e.g. duloxetine) are also included depending on the type of symptoms. In mixed incontinence the predominant symptom should be treated first. When this initial treatment is ineffective, further investigation should be offered prior to specialised treatment. Urodynamics should be considered for all patients prior to surgery. Imaging and cystoscopy to exclude pathology, for example in elderly patients with an overactive bladder, are also necessary. Newer surgical interventions should be offered after careful consideration of the risk:benefit ratio for each individual woman and the amount of evidence that is currently available to support their use.  相似文献   
9.
混合Poisson分布及其应用:疾病的统计分布(五)   总被引:4,自引:0,他引:4  
本文讨论了混合Poisson分布的性质、应用条件、参数的估计及混合Poisson分布阶数的确定,指出混合Poisson分布可用于混合样本的判别归类,并用Bayes的思想导出其判别归类方法。模拟试验结果表明:当混合Poisson分布中各部分的比例相差不大,而各部分的均值相差较大时,抽样效果和拟合效果越好,所得到的估计值越接近理论值;反之效果越差。  相似文献   
10.
目的评价复方角菜酸酯栓对缓解痔上黏膜环形切除钉合术(PPH)后患者早期不适症状方面的疗效。方法选取2002年11月至2003年7月行PPH的80例患者,随机分为治疗组(复方角菜酸酯栓组,42例)和对照组(常规处理组,38例),分别记录两组患者术后24h和第6及第12天时的症状改善情况、术后24h有无尿潴留情况、术后首次排便时间、试验结束时伤口愈合情况、住院时间和换药次数、停药及停药的原因以及伴随用药情况。结果术后24h治疗组患者症状总得分(4.4)较对照组(6.1)低,P<0.05。但至术后第6和第12天时,两组症状得分比较,差异无统计学意义(P>0.05)。治疗组患者在各时间点的症状得分减少值均高于对照组(P<0.05)。两组患者在术后24h出现尿潴留的比率和住院天数方面比较,差异无统计学意义(P>0.05)。结论复方角菜酸酯栓对于缓解PPH术后早期的不适症状效果良好。  相似文献   
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