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Skin grafts are frequently used for the reconstruction of skin defects, and optimal stabilization of the graft is essential for successful reconstruction. Although the tie‐over technique has been widely used as a standard method in Japan, we sometimes encounter cases with significant graft loss due to suboptimal stabilization of the graft. Reported risk factors for increased graft loss include the following: defects of a large size, with muscle exposure, and located in the trunk and extremities. Recent studies have demonstrated the usefulness of negative‐pressure closure (NPC) for the stabilization of skin grafts due to the uniform pressure it provides across the graft. Therefore, since March 2017, we have used NPC for skin graft stabilization in patients with defects in the trunk and extremities of more than 10 cm in size or with muscle exposure. We carried out a retrospective comparative study of the outcome of the conventional tie‐over technique versus NPC. Mann–Whitney U‐test revealed that NPC showed significantly higher graft survival rate than tie‐over method (P = 0.0012). In addition, NPC showed a tendency toward shorter operative times (from skin graft harvest to the completion of the graft stabilization) than the tie‐over method (P = 0.0931). These results suggest that NPC may be superior to the tie‐over method for stabilization of skin grafts especially in large or muscle‐exposing defects in the trunk or extremities.  相似文献   
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人工瓣膜置换术后心内血栓包括人工瓣膜血栓和左心房血栓,是心脏瓣膜置换术后最严重的并发症之一,其中人工瓣膜血栓每年的发生率为0.2%~6%[1]。目前对瓣膜置换术后心内血栓的治疗主要为溶栓疗法及手术治疗。手术风险较大、费用高;溶栓治疗费用低、风险小,但在诸多方面存在着争议。现回顾性分析2010年9月-2014年6月在笔者医院住院的29例人工瓣膜置换术后心内血栓患者予以尿激酶溶栓治疗的临床资料,报告如下。  相似文献   
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PurposeCrucial steps have been adopted by health and regulatory authorities around the world to respond to the COVID-19 pandemic. This review aims to highlight these steps by providing an overview of the regulatory approaches adopted during the onset of the pandemic, provide an assessment of observed trends, and offer some reflections and proposals to leverage learnings and opportunities from this current pandemic.MethodsDocuments and informational materials on regulating the development and management of medical products during the COVID-19 pandemic were collected and classified. These materials were sourced from official websites and press releases from health authorities and international bodies from selected markets across the globe, and covered the period between January and July 2020. Additional information to support this study was gathered through a literature review and analysis of related data available from the public domain, and was complemented with the authors' personal experience.FindingsCommunication has been vital in addressing the impact of COVID-19. A total of 1705 documents and informational materials related to health or regulatory response to the COVID-19 pandemic were gathered. Of these, 343 (around 20%) were identified as regulatory agilities. These agile approaches were classified into 3 categories, namely, where health and regulatory authorities had: (1) facilitated product management across the entire lifecycle, notably in expediting medical product use for COVID-19, ensuring the continuity of clinical trials, and addressing supply chain issues; (2) strengthened international cooperation; and (3) addressed regulatory burden with the adoption of electronic and digital tools.ImplicationsWhile many regulatory measures have been introduced temporarily as a response to the COVID-19 crisis, there are opportunities for leveraging an understanding from these approaches in order to collectively achieve more efficient regulatory systems and to mitigate and address the impact of COVID-19 and further future-proof the regulatory environment.  相似文献   
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BACKGROUND Although several techniques for endoscopic ultrasound-guided biliary drainage(EUS-BD)are available at present,an optimal treatment algorithm of EUS-BD has not yet been established.AIM To evaluate the clinical utility of treatment method conversion during single endoscopic sessions for difficult cases in initially planned EUS-BD.METHODS This was a single-center retrospective analysis using a prospectively accumulated database.Patients with biliary obstruction undergoing EUS-BD between May 2008 and April 2016 were included.The primary outcome was to evaluate the improvement in EUS-BD success rates by converting the treatment methods during a single endoscopic session.Secondary outcomes were clarification of the factors leading to the conversion from the initial EUS-BD and the assessment of efficacy and safety of the conversion as judged by technical success,clinical success,and adverse events(AEs).RESULTS A total of 208 patients underwent EUS-BD during the study period.For 18.8%(39/208)of the patients,the treatment methods were converted to another EUSBD technique from the initial plan.Biliary obstruction was caused by pancreatobiliary malignancies,other malignant lesions,biliary stones,and other benign lesions in 22,11,4,and 2 patients,respectively.The reasons for the difficulty with the initial EUS-BD were classified into the following 3 procedures:Target puncture(n=13),guidewire manipulation(n=18),and puncture tract dilation(n=8).Technical success was achieved in 97.4%(38/39)of the cases and clinical success was achieved in 89.5%of patients(34/38).AEs occurred in 10.3%of patients,including bile leakage(n=2),bleeding(n=1),and cholecystitis(n=1).The puncture target and drainage technique were altered in subsequent EUSBD procedures in 25 and 14 patients,respectively.The final technical success rate with 95%CI for all 208 cases was 97.1%(95%CI:93.8%-98.9%),while that of the initially planned EUS-BD was 78.8%(95%CI:72.6%-84.2%).CONCLUSION Among multi-step procedures in EUS-BD,guidewire manipulation appeared to be the most technically challenging.When initially planned EUS-BD is technically difficult,treatment method conversion in a single endoscopic session may result in successful EUS-BD without leading to severe AEs.  相似文献   
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Cognitive impairment has long been recognized as a complication of chronic kidney disease. However, there is little information available regarding regional cerebral blood flow (rCBF) in patients with peritoneal dialysis (PD). Therefore, we evaluated rCBF using brain single photon emission computed tomography (SPECT). We conducted a cross‐sectional study in our hospital. Eighteen consecutive PD patients who could visit the hospital by themselves without any history of stroke were examined by Technetium‐99 m‐labeled ethylcrysteinate dimer brain SPECT. An easy Z‐score imaging system (eZIS) was used to compare rCBF in PD patients with those in age‐matched healthy controls. We also evaluated cognitive dysfunction with the mini‐mental state examination (MMSE) questionnaire. Only one patient showed an MMSE score of 18 points, and the remaining 14 patients were considered as normal (MMSE ≥ 27), and three patients were considered to have mild cognitive impairment (24 ≤ MMSE ≤ 26). In all patients, rCBF in the posterior cingulated gyri, precunei, and parietal cortices was significantly decreased. The ratio of the reduction of rCBF in each region relative to that of rCBF across the whole brain correlated positively with the PD duration (r = 0.559; P < 0.05). The serum β2‐microglobulin level was significantly higher in patients who had a higher ratio of rCBF reduction compared with those with lower ratios. In conclusion, all PD patients in the present study had decreased rCBF irrespective of MMSE scores.  相似文献   
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