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1.
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   
2.
丙型肝炎病毒(HCV)RNA可通过直接抗病毒药物治疗从血液循环中清除,达到持续病毒学应答(SVR)。研究表明,直接抗病毒药物治疗达到SVR后,可降低肝细胞癌(HCC)发病率,但仍需监测HCC的发生。现简要总结现有研究关于抗病毒治疗后丙型肝炎继发HCC可能原因的讨论,主要分为表观遗传学改变与DNA异常甲基化、HCV相关肝硬化与DNA倍数异常、HBV再激活、隐匿性HCV感染几个方面,以及抗病毒治疗对HCC复发的影响。抗病毒治疗在极少数情况下不能完全阻止丙型肝炎后HCC的发生和复发,其机制仍需继续研究探索,临床医生也应谨慎对待。  相似文献   
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4.
Tsukamurella species are obligate aerobic, gram-positive, weak acid-fast, nonmotile bacilli. They are found in various environments, such as soil, water, sludge, and petroleum reservoir wastewater, and belong to the order Actinomycetales. In 2016, there was a reclassification of species within the genus Tsukamurella, merging the species Tsukamurella tyrosinosolvens (T. tyrosinosolvens) and Tsukamurella carboxydivorans. Tsukamurella species are clinically considered to be a rare opportunistic pathogen, because most reported cases have been related to bacteremia and intravascular prosthetic devices and immunosuppression. To date, it has been isolated only from human specimens, and has always been associated with clinical disease; human infections are very rare. Reported infections have included pneumonia, brain abscesses, catheter-related bloodstream infections, ocular infections, bacteremia, and sepsis presenting with septic pulmonary emboli in patients who are immunocompromised. To date, there is no commercially available test for identification. On the other hand, sequence-based identification, including matrix-assisted laser desorption ionization time-of-flight mass spectrometry, is an alternative method for identifying clinical isolates that are either slow growers or difficult to identify through biochemical profiling. The golden standards for diagnosis and optimal management still remain to be determined. However, newer molecular biological techniques can provide accurate identification, and contribute to the appropriate selection of definitive therapy for infections caused by this organism. Combinations of several antimicrobial agents have been proposed for treatment, though the length of treatment for infections has yet to be determined, and should be individualized according to clinical response. Immunocompromised patients often experience severe cases due to infection, and life-threatening T. tyrosinosolvens events associated with dissemination and/or failure of source control have occurred. Favorable prognoses can be achieved through earlier identification of the cause of infection, as well as successful management, including appropriate antibiotic therapy together with source control. Further analyses of similar cases are required to establish the most adequate diagnostic methods and treatment regimens for infections.  相似文献   
5.
[摘要]?目的?结合环介导等温扩增技术(loop-mediated isothermal amplification, LAMP)和微流控芯片技术,建立一种适合现场快速检测登革病毒的方法。方法?利用RT-LAMP,针对登革病毒基因组中3’非编码区中特异性序列进行扩增,建立基于微流控芯片技术的LAMP检测方法,优化检测体系,并对该方法的灵敏性和特异性进行评估。结果?基于LAMP 和微流控芯片技术的登革病毒检测方法,通过对病毒模板进行扩增,发现与其他病毒无交叉反应,特异性良好;同时,结果显示该方法对登革病毒检测灵敏性可达61.2 pg/μl,与实时荧光定量PCR仪所达到的检测灵敏性一致。结论?基于LAMP和微流控芯片技术的登革病毒检测方法具有操作简单、快速、对设备要求低等优势,并且灵敏性、特异性均较好,是一种便于开展现场快速检测的方法。  相似文献   
6.
目的 建立一种能够快速鉴定人参和西洋参的双重实时荧光PCR方法。方法 通过对人参属及其近似种基因序列的分析比对,设计特异性的引物探针,建立双重实时荧光PCR检测方法。PCR反应体系为Premix Ex Taq (Probe qPCR) 10 μL,人参上下游引物各0.5 μL,西洋参上下游引物各0.3 μL,人参与西洋参特异性探针各0.4 μL,DNA模板2 μL,灭菌去离子水补至20 μL。反应条件为95℃预变性30 s;然后以95℃变性5 s,60℃退火延伸30 s进行40个循环。应用该方法测试了27份DNA样品,包括7份人参、6份西洋参、4份人参与西洋参混合样、10份其他人参属样品及其他常见中药材样品的DNA,以确定该方法的特异性。将人参与西洋参样品DNA混合后10倍稀释成不同浓度后进行检测,用以确定该方法的灵敏度。结果 人参及西洋参样品均在特定的荧光通道下出现典型的阳性扩增曲线,人参与西洋参混合样品均同时出现两条阳性扩增曲线,其它对照样品及空白对照均没有出现阳性扩增曲线。灵敏度检测结果显示该方法检测人参及西洋参的最低检测限均为2 pg DNA/反应。结论 本实验建立的双重实时荧光PCR方法能够同时快速、准确、灵敏地鉴别出人参和西洋参。  相似文献   
7.
This study evaluates the impact of tooth-borne Surgically Assisted Rapid Mandibular Expansion (SARME) on the temporomandibular joint (TMJ) function and condylar morphology.Medical records of patients who received a SARME between 2014 and 2018 are retrospectively reviewed concerning functional problems. Morphological changes of the condyles are analyzed by means of surface registration of 3D reconstructed CBCT scans preoperatively and one-year postoperatively, and correlated to functional outcome.In 68 patients data are complete. The risk of TMJ dysfunction is slightly increased from 18 to 25% at a mean of 14 months after SARME. This is attributed to an increase in the number of minor problems (75–82%). The presence of complaints before SARME is the only identifiable risk factor for also having complaints after the intervention (p = 0.0019). In one patient with pre-existent TMJ dysfunction complaints deteriorated after SARME. After SARME no cases of extended condylar resorption are described. There is no correlation between morphological condylar changes and the prevalence of TMJ dysfunction (p = 0.7121 for appositional and p = 0.3038 for resorptive changes). However, appositional and resorptive changes at the condylar head appear to correlate with growth potential, based on age, gender and skeletal deformity (p < 0.0001 and p = 0.0154 respectively).Within the limitations of the study it seems that SARME does not have a negative impact on TMJ function or condylar integrity and, therefore, the choice for or against this approach can be made without considering consequences for TMJ a major issue for the decision.  相似文献   
8.
目的 探讨新型国产经口胆胰直视化子镜系统诊治胆胰疾病的有效性和安全性。方法 回顾性分析2020年4月—2021年6月在南京大学医学院附属鼓楼医院消化内镜中心行国产经口胆胰直视化子镜系统检查的37例患者资料,分析内镜检查的技术成功率和并发症发生情况。结果 37例患者均完成国产经口胆胰直视化子镜系统检查,技术成功率100.0%。明确胆管狭窄性质24例,观察胆管有无出血或结石残留6例,观察胰管有无新生物或结石残留2例,直视下辅助导丝通过胆管狭窄2例,直视下辅助胆道激光碎石3例。共9例患者病理确诊为恶性胆管狭窄,其中8例通过经口胆胰直视化子镜系统视觉判断为恶性病变。经口胆胰直视化子镜系统检查后,胆胰管引流34例。术后发生胆管炎3例、菌血症4例、胰腺炎2例,均保守治疗后短期内好转;出血1例,经2次内镜下止血后好转。结论 新型国产经口胆胰直视化子镜系统在胆胰疾病诊治中安全、有效。  相似文献   
9.
目的分析高频彩色多普勒超声在老年腹股沟斜疝、直疝及股疝中的应用价值。 方法将2019年11月至2021年11月在庐江县人民医院收治的140例诊断为腹股沟疝的老年患者为研究对象,分析患者临床资料。全部患者均接受高频彩色多普勒超声检查,经手术探查,分析斜疝、直疝及股疝的不同超声影像表现,对比分析超声检出率与准确率。 结果高频彩色多普勒超声检查,直疝所占比例为15.94%;其中斜疝所占比率最多为78.26%,股疝所占比率为5.80%。所有患者经手术验证:腹股沟直疝的准确率为100%;腹股沟斜疝中,易复性疝准确率为97.78%,难复性疝为100%,嵌顿性疝为100%,绞窄性疝为100%,股疝为100.00%。所有病例超声检测准确率为98.57%。 结论高频彩色多普勒超声在老年腹股沟斜疝、直疝及股疝中的诊断价值较高,能有效对腹外疝的分型做出准确判断,值得临床推广。  相似文献   
10.
Forensic age estimation is an invaluable aspect of human identification. Out of these many means of age estimation, few regions with untapped potential for assistance in forensic age estimation are the age-related changes in the laryngeal cartilages. As the age advances, the thyroid and cricoid cartilages undergo gradual calcification in an individual. These age-related changes can be visualized in both the living and the dead using conventional radiography and can be objectively assessed. The objective of the present study was to evaluate the age-related changes in the laryngeal cartilages and the results may be utilized for age estimation in forensic examinations. The laryngeal cartilages were carefully dissected using standard procedures from 75 cadavers of age ranging from 17 to 65 years, during the post-mortem examination. The laryngeal cartilages were radiographed and replaced in the body cavity before culminating the post-mortem examination. The calcification of both cartilages was studied by using the standard grading method. Calcification scores of individual regions of both the laryngeal cartilages show a statistically significant positive correlation with chronological age (P < 0.05). Regression models derived from the degree of calcification of thyroid and cricoid cartilages showed standard error of estimates that ranged between 9.90 and 11.07 years. Considering the standard error of estimates of the regression analysis, the present study concludes that these regression models can be used in adjunct with other methods of age estimation such as the skeletal and dental age or when such methods are not viable as in cases of charred or mutilated remains.  相似文献   
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