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Approximately 10%-20% of the cases of acute pancreatitis have acute necrotizing pancreatitis. The infection of pancreatic necrosis is typically associated with a prolonged course and poor prognosis. The multidisciplinary, minimally invasive “step-up” approach is the cornerstone of the management of infected pancreatic necrosis (IPN). Endosonography-guided transmural drainage and debridement is the preferred and minimally invasive technique for those with IPN. However, it is technically not feasible in patients with early pancreatic/peripancreatic fluid collections (PFC) (< 2-4 wk) where the wall has not formed; in PFC in paracolic gutters/pelvis; or in walled off pancreatic necrosis (WOPN) distant from the stomach/duodenum. Percutaneous drainage of these infected PFC or WOPN provides rapid infection control and patient stabilization. In a subset of patients where sepsis persists and necrosectomy is needed, the sinus drain tract between WOPN and skin-established after percutaneous drainage or surgical necrosectomy drain, can be used for percutaneous direct endoscopic necrosectomy (PDEN). There have been technical advances in PDEN over the last two decades. An esophageal fully covered self-expandable metal stent, like the lumen-apposing metal stent used in transmural direct endoscopic necrosectomy, keeps the drainage tract patent and allows easy and multiple passes of the flexible endoscope while performing PDEN. There are several advantages to the PDEN procedure. In expert hands, PDEN appears to be an effective, safe, and minimally invasive adjunct to the management of IPN and may particularly be considered when a conventional drain is in situ by virtue of previous percutaneous or surgical intervention. In this current review, we summarize the indications, techniques, advantages, and disadvantages of PDEN. In addition, we describe two cases of PDEN in distinct clinical situations, followed by a review of the most recent literature.  相似文献   
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【摘要】 目的:应用CT血管造影多平面重建(CT angiography multiplanar reconstruction,CTA MPR)测量枢椎椎弓根峡部复合体(pediculoisthmic component,PIC)最狭窄部位尺寸,评估枢椎椎弓根螺钉置钉的安全性(CTA MPR测量法),并与CT标准水平轴位测量评估方法(CT AXIS测量法)、椎动脉高跨变异(high-riding vertebral artery,HRVA)评估方法(HRVA定义法)对比,评价两种临床常用术前评估方法的假阳性率和假阴性率。方法:选取已行普通CT平扫及头颈部CTA检查的152例患者作为研究对象,使用CT AXIS测量法测量患者枢椎双侧椎弓根髓腔宽度(a1)及外径宽度(a2);使用CT骨窗正中矢状位测量患者枢椎双侧椎管内壁外侧3mm处的峡部高度(b)及侧块内高(c),并定义是否存在HRVA;使用CTA MPR测量法测量枢椎PIC最狭窄部的髓腔宽度(d1)、外径宽度(d2)、髓腔高度(e1)及外径高度(e2)。比较CT AXIS测量法测量参数与CTA MPR测量法测量参数的差异,计算三种方法判定不适合安全置入枢椎椎弓根螺钉的比例,并以CTA MPR测量法作为判定金标准,评价CT AXIS测量法和HRVA定义法的假阳性率和假阴性率。结果:使用CTA MPR测量法与CT AXIS测量法分别测量152例患者的304个枢椎椎弓根峡部尺寸,两种方法测量的髓腔宽度(3.82±1.58mm vs 2.55±1.16mm)和外径宽度(6.54±1.91mm vs 5.48±1.49mm)均有统计学差异(P<0.001);CTA MPR测量PIC的高度显著大于其宽度(髓腔:6.55±1.34mm vs 3.82±1.58mm;外径:10.20±1.22mm vs 6.54±1.91mm)(P<0.001)。以CTA MPR测量法作为判定金标准,CT AXIS测量法的假阴性率为6.91%,假阳性率为20.69%;HRVA定义法的假阴性率为11.64%,假阳性率为3.45%。CTA MPR测量法与CT AXIS测量法、HRVA定义法评估置钉可行性之间存在显著性差异(P<0.01)。结论:CTA MPR测量法可模拟枢椎椎弓根钉道,获取钉道最狭窄部重建截面并准确测量宽度,是术前评估枢椎椎弓根螺钉安全置钉可行性的准确方法。CT AXIS测量法与HRVA定义法均存在一定的假阳性率和假阴性率,可能导致误判或漏判置钉可行性,从而增加椎动脉损伤的风险或选择生物力学性能不足的置钉术式。  相似文献   
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Recent epidemiological studies suggested that proton pump inhibitor (PPI) use was associated with an increased risk of biliary tract cancer (BTC), however, confounders were not adequately controlled. Our study aimed to evaluate PPI use and subsequent risk of BTC and its subtypes in three well-established cohorts. We conducted a pooled analysis of the subjects free of cancers in UK Biobank (n = 463 643), Nurses' Health Study (NHS, n = 80 235) and NHS II (n = 95 869). Propensity score weighted Cox models were used to estimate marginal HRs of PPIs use on BTC risk, accounting for potential confounders. We documented 284 BTC cases in UK Biobank (median follow-up: 7.6 years), and 91 cases in NHS and NHS II cohorts (median follow-up: 15.8 years). In UK biobank, PPI users had a 96% higher risk of BTC compared to nonusers in crude model (HR 1.96, 95% CI 1.44-2.66), but the effect was attenuated to null after adjusting for potential confounders (HR 0.95, 95% CI 0.60-1.49). PPI use was not associated with risk of BTC in the pooled analysis of three cohorts (HR 0.93, 95% CI 0.60-1.43). We also observed no associations between PPI use with risk of intrahepatic (HR 1.00, 95% CI 0.49-2.04), extrahepatic bile duct (HR 1.09, 95% CI 0.52-2.27) and gallbladder cancers (HR 0.66, 95% CI 0.26-1.66) in UK Biobank. In summary, regular use of PPIs was not associated with the risk of BTC and its subtypes.  相似文献   
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BackgroundStaphylococcus epidermidis is a common cause of health care-associated bacteremia, especially in patients with an indwelling medical device. However, S. epidermidis is an uncommon causative organism in catheter-associated urinary tract infection, and rare pyelonephritis without any indwelling urinary device. To our knowledge, there are few cases reported of bacteremia secondary to urinary tract infection. We report two cases of pyelonephritis with bacteremia by S. epidermidis in male patients with unilateral nephrolithiasis and review prior case reports.Case presentationCase 1: 74-year-old man with a history of diabetes and overactive bladder had fever and pyuria with a right nephrolithiasis on abdominal CT scan. Case 2: 79-year-old man with a history of diabetes and post-myocardial infarction status had fever with a left nephrolithiasis on abdominal CT scan. In both cases, both the urine culture collected at ureteral stenting and blood culture were positive for S. epidermidis. We initiated intravenous antibiotics in these patients in addition to ureteral stenting.ConclusionsS. epidermidis is acknowledged as an uncommon pathogen that can cause bacteremia secondary to pyelonephritis without an indwelling urinary device. Clinicians should consider the possibility of pyelonephritis due to S. epidermidis if the pathogen is identified in blood and urine in patients with nephrolithiasis.  相似文献   
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目的 了解我国老年乳腺癌患者乳房重建手术决策过程的体验。方法 采用目的抽样法选取2021年4月—2022年5月在天津某三级甲等医院就诊的乳腺癌患者进行半结构式访谈。运用Clolaizzi 7步分析法对资料进行整理分析,进行主题描述。结果 提炼出4个主题:内心感知的痛苦;决策的困境;决策的动机;期待决策支持。结论 本研究深入探索我国老年乳腺癌患者乳房重建决策体验,为向老年乳腺癌患者开展更具有针对性决策辅助干预措施提供理论依据。  相似文献   
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A priori subcell limiting approach is developed for high-order flux reconstruction/correction procedure via reconstruction (FR/CPR) methods on two-dimensional unstructured quadrilateral meshes. Firstly, a modified indicator based on modal energy coefficients is proposed to detect troubled cells, where discontinuities exist. Then, troubled cells are decomposed into nonuniform subcells and each subcell has one solution point. A second-order finite difference shock-capturing scheme based on nonuniform nonlinear weighted (NNW) interpolation is constructed to perform the calculation on troubled cells while smooth cells are calculated by the CPR method. Numerical investigations show that the proposed subcell limiting strategy on unstructured quadrilateral meshes is robust in shock-capturing.  相似文献   
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