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71.
Pancreatic somatostatinoma is a rare pancreatic endocrine neoplasm representing as little as 1% of pancreatic endocrine neoplasms (PENs). The histologic features of this tumor are like those of other PENs, except that it commonly forms acinar structures and often has cells with abundant, granular cytoplasm. We have recently encountered two of these neoplasms sampled by endoscopic ultrasound (EUS)-guided fine-needle aspiration (FNA). We discuss the cytologic and immunohistochemical findings of these two cases and the cytologic similarities these neoplasms share with pancreatic acinar-cell carcinoma (PACC). We review the cytologic features of PEN and PACC and discuss the importance of cell block immunohistochemistry in the diagnosis of pancreatic neoplasia sampled by EUS-guided FNA.  相似文献   
72.
A wireless power transfer system for endoscopic micro-robot operating at 36 kHz is presented in this paper. The issue of patient' s health and safety regarding exposure to the electromagnetic field is addressed. The specific absorption rate and current density can be used to investigate the electromagnetic influences on the biological tissues surrounded by the wireless power launching coil. In view of this purpose, the limited close-ound solenoid electromagnetic model is built, the relationship between the electric intensity and the specific absorption rate and current density is deduced, and the simulation experiments are done. Experimental results show that the values of SAR and current density related to different tissue catalogs are all very small and do not exceed their own limits respectively when the resonance frequency of operation is 36 kHz.  相似文献   
73.
Endoscopic ultrasound (EUS) has allowed for the fine-needle aspiration and diagnosis of many different gastrointestinal neoplasms, including mesenchymal tumors. Although most mesenchymal tumors of the gastrointestinal tract are gastrointestinal stromal tumors (GISTs), other mesenchymal tumors, including neural tumors, do occur. Proper diagnosis and differentiation of these tumors from GISTs are important because of their different prognoses and treatment regimens. We encountered three peripheral nerve-sheath tumors of the gastrointestinal tract aspirated by EUS (two schwannomas and a granular-cell tumor). We report on the endoscopic ultrasound, cytologic, histologic, and immunohistochemical findings of these cases.  相似文献   
74.
BACKGROUND: Endometriosis and possible rectal involvement are difficult to assess by physical examination. Previous studies have shown the diagnostic value of magnetic resonance imaging and rectal endoscopic sonography (RES) in this setting, but not that of transvaginal sonography (TVS). The aims of this study were to compare the accuracy of TVS and RES for the diagnosis of pelvic endometriosis, and to compare the results with histological findings. PATIENTS AND METHODS: In a prospective study, 30 consecutive patients referred with clinical signs of endometriosis underwent TVS and RES; the images were interpreted blindly with regard to physical findings. RESULTS: Endometriosis was confirmed histologically in 28 (93%) of the 30 patients. Endometriomas were also present in 67% of cases. For the diagnosis of uterosacral endometriosis, the sensitivity, specificity, and positive and negative predictive values of TVS and RES were 75 and 75%, 83 and 67, 95 and 90%, and 45 and 40% respectively. For the diagnosis of rectosigmoid endometriosis, the sensitivity, specificity, and positive and negative predictive values of TVS and RES were 95 and 82%, 100 and 88%, 100 and 95%, and 89 and 64% respectively. CONCLUSION: Despite the large proportion of our patients who had intestinal endometriosis, representing a possible source of bias, our results suggest that TVS is as efficient as RES for detecting posterior pelvic endometriosis and should therefore be used as the first-line examination.  相似文献   
75.
 目的 探讨过氧乙酸和环氧乙烷两种不同方法对胰腺包裹性坏死(WON)并多重耐药菌(MDRO)感染(经皮/经胃)内镜下清创术内镜的灭菌效果。方法 选取江西省某三级甲等医院WON并MDRO感染(经皮/经胃)内镜下清创术患者使用带副送水功能的内镜,采用随机数字表法将其分为两组:A组采用过氧乙酸浸泡灭菌,B组采用环氧乙烷低温灭菌。滤膜法采集内镜的钳子管道、送气/送水管道和副送水管道3个位点标本进行微生物培养,比较两组内镜灭菌合格率、菌落数和检出MDRO情况。结果 共采集78条副送水内镜,A组和B组各39条,共234份标本,A组和B组内镜灭菌合格率分别为61.54%、100%。A组钳子管道灭菌合格率为82.05%,送气/送水管道灭菌合格率为89.74%, 副送水管道灭菌合格率为74.36%,B组3个位点灭菌合格率均为100%。A组钳子管道、送气/送水管道和副送水管道菌落总数范围分别为0~6、0~112、0~23 CFU,分离MDRO 36株,以多重耐药铜绿假单胞菌、耐甲氧西林金黄色葡萄球菌和多重耐药肺炎克雷伯菌为主。将A组15条不合格的内镜转为环氧乙烷低温灭菌后,微生物学监测合格率达100%。结论 对于WON并MDRO感染(经皮/经胃)内镜下清创术的内镜,环氧乙烷低温灭菌方法更有效。对内镜的微生物学监测不能仅局限于钳子管道的监测,带副送水功能的内镜需监测副送水管道,以降低感染风险。  相似文献   
76.
We aimed to evaluate the learning curve of the surgically standardised ‘Omega Sign’ anatomical endoscopic enucleation (AEEP) of the prostate surgery technique for junior surgeons. This study is a retrospective comparison of cases that underwent AEEP by a mentor surgeon and three junior surgeons who have completed their learning curve. A video-based laser enucleation of the prostate assessment tool (LEAT) composed of 8 steps of the technique was used to assess a senior surgeon and junior surgeons’ surgical compatibility and consistency. The surgeon who defined Omega Sign technique was determined as group 1, and cases by three junior surgeons were identified as group 2. The end points were to assess the reproducibility and repeatability and operative post-operative outcomes of the technique. 55 patients’ videos were rated by five experienced endourologists. There was no significant difference in LEAT scores between the groups among all steps. The most symmetry was found in the 1st and 3rd steps. Inter-rater consistency was also high for each step, with no statistically significant difference between the evaluators. The standardised anatomical ‘Omega Sign’ technique is reproducible for the junior surgeons. The operative steps can be performed with high consistency, and the functional and perioperative outcomes are comparable with the senior surgeon.  相似文献   
77.
78.
The learning curve for novices developing regional anaesthesia skills, such as real-time ultrasound-guided needle manipulation, may be affected by innate visuospatial ability, as this influences spatial cognition and motor co-ordination. We conducted a multinational randomised controlled trial to test if novices with low visuospatial ability would perform better at an ultrasound-guided needling task with deliberate practice training than with discovery learning. Visuospatial ability was evaluated using the mental rotations test-A. We recruited 140 medical students and randomly allocated them into low-ability control (discovery learning), low-ability intervention (received deliberate practice), high-ability control, and high-ability intervention groups. Primary outcome was the time taken to complete the needling task, and there was no significant difference between groups: median (IQR [range]) low-ability control 125 s (69–237 [43–600 s]); low-ability intervention 163 s (116–276 [44–600 s]); high-ability control 130 s (80–210 [41–384 s]); and high-ability intervention 177 s (113–285 [43–547 s]), p = 0.06. No difference was found using the global rating scale: mean (95%CI) low-ability control 53% (95%CI 46–60%); low-ability intervention 61% (95%CI 53–68%); high-ability control 63% (95%CI 56–70%); and high-ability intervention 66% (95%CI 60–72%), p = 0.05. For overall procedure pass/fail, the low-ability control group pass rate of 42% (14/33) was significantly less than the other three groups: low-ability intervention 69% (25/36); high-ability control 68% (25/37); and high-ability intervention 85% (29/34) p = 0.003. Further research is required to determine the role of visuospatial ability screening in training for ultrasound-guided needle skills.  相似文献   
79.
翟正佳  董健文  刘仲宇 《中国骨伤》2021,34(11):1087-1090
经椎间孔入路全内镜下腰椎椎体间融合术(full endoscopic transforaminal lumbar interbody fusion)近年来在微创脊柱外科领域获得广泛应用,本文简要介绍该术式的发展历史、技术要点、适应证、疗效以及并发症。笔者认为经椎间孔入路全内镜下腰椎椎体间融合术具有与传统手术同样的临床效果,并且能够有效减少组织损伤和术中出血、降低术后腰背痛的发生率、缩短术后下床活动时间及平均住院日,但仍需完善远期随访,以进一步评估该术式的有效性和安全性。  相似文献   
80.
年轻乳腺癌病人预后较差,与侵袭性生物学特征密切相关,是临床治疗的一大难点。年轻女性乳腺癌病人的外科手术抉择需要综合权衡肿瘤生物学特征、病人的自身需求、社会家庭支持因素等各个方面。对于早期肿瘤应当积极开展保乳手术,对于临床分期较晚的肿瘤,建议参照分子分型积极开展新辅助治疗,或者实施合适的乳房重建技术。临床医师应当为病人提供更加充分的信息与高级别的循证医学证据,鼓励病人积极参与外科手术决策的制定。  相似文献   
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