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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   
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赵智勇  张娜 《医学综述》2015,21(1):135-136
目的探讨嵌顿痔不同治疗方法的疗效。方法回顾性分析2009年8月至2012年8月迁西县人民医院确诊为嵌顿痔的160例患者的临床资料,其中采取外剥内扎法的80例患者作为A组,吻合器痔上黏膜环切术(PPH)结合外痔血栓剥除术的80例患者作为B组。对比分析两组患者的手术时间、住院时间、住院费用等指标及临床疗效,对比分析两组术后6个月并发症发生情况。结果B组患者的手术时间、住院时间显著少于A组[(15.4±1.1)min比(38.7±0.5)min,(5.3±0.6)d比(12.4±1.3)d,P<0.01];B组患者的有效率显著高于A组(88.8%比66.3%),而总体并发症发生率及复发率显著低于A组(17.5%比33.8%,5%比18.8%,P<0.05)。结论 PPH结合外痔血栓剥除术临床疗效显著。  相似文献   
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.
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   
7.
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   
8.
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   
9.
胆石症是一种常见病,鹅去氧胆酸(CDCA)可用于胆固醇胆石症的治疗。它能改变胆汁组成,降低胆汁内胆固醇饱和度,增加胆固醇溶解性,使胆石逐渐溶解。但CDCA易被肠道内细菌7-脱羟酶作用生成石胆酸(LC),引起腹泄、腹部痉挛、高转  相似文献   
10.
目的探讨保留齿状线加皮桥重建闭合切口治疗环状混合痔的可行性及疗效。方法治疗组选用保留齿状线加皮桥重建闭合切口32例,与对照组采用传统外剥内扎治疗34例在术后疼痛、水肿、出血、痔残留等并发症及住院时间、愈合时间等方面进行比较。结果治疗组在术后疼痛、水肿、出血、痔残留等及住院时间、愈合时间等方面均优于对照组。结论保留齿状线加皮桥重建闭合切口治疗环状混合痔安全、有效、可行。  相似文献   
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