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1.
IntroductionThere is still no consensus in the literature as to the best acoustic stimulus for capturing vestibular evoked myogenic potential (VEMP). Low-frequency tone bursts are generally more effective than high-frequency, but recent studies still use clicks. Reproducibility is an important analytical parameter to observe the reliability of responses.ObjectiveTo determine the reproducibility of p13 and n23 latency and amplitude of the VEMP for stimuli with different tone-burst frequencies, and to define the best test frequency.MethodsCross-sectional cohort study. VEMP was captured in 156 ears, on the sternocleidomastoid muscle, using 100 tone-burst stimuli at frequencies of 250, 500, 1000, and 2000 Hz, and sound intensity of 95 dB nHL. Responses were replicated, that is, recorded three times on each side.ResultsNo significant difference was observed for p13 and n23 latencies of the VEMP, captured at three moments with tone-burst stimuli at 250, 500, and 1000 Hz. Only the frequency of 2000 Hz showed a difference between captures of this potential (p < 0.001). p13 and n23 amplitude analysis was also similar in the test–retest for all frequencies analyzed.Conclusionp13 and n23 latencies and amplitudes of VEMP for tone-burst stimuli at frequencies of 250, 500, and 1000 Hz are reproducible.  相似文献   
2.
AimsPatient factors affect the risk of radiotherapy toxicity, but many are poorly defined. Studies have shown that race affects cancer incidence, survival, drug response, molecular pathways and epigenetics. Effects on radiosensitivity and radiotherapy toxicity are not well studied. The aim of the present study was to identify the effects of race and ethnicity on the risk of radiotherapy toxicity.Materials and methodsA systematic review was carried out of PubMed, Ovid Medline and Ovid Embase with no year limit. PRISMA 2020 guidelines were followed. Two independent assessors reviewed papers.ResultsOf 607 papers screened, 46 fulfilled the inclusion criteria. Papers were published between 1996 and 2021 and involved 30–28,354 individuals (median 433). Most involved patients with prostate (33%), breast (26%) and lung (9%) cancer. Both early and late toxicities were studied. Some studies reported a higher risk of toxicity in White men with prostate cancer compared with other races and ethnicities. For breast cancer patients, some reported an increased risk of toxicity in White women compared with other race and ethnic groups. In general, it was difficult to draw conclusions due to insufficient reporting and analysis of race and ethnicity in published literature.ConclusionsReporting of race and ethnicity in radiotherapy studies must be harmonised and improved and frameworks are needed to improve the quality of reporting. Further research is needed to understand how ancestral heritage might affect radiosensitivity and risk of radiotherapy toxicity.  相似文献   
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4.
人胚雪旺细胞组织工程神经修复坐骨神经缺损的实验研究   总被引:1,自引:0,他引:1  
目的:探索人胚雪旺细胞作为组织工程的种子细胞修复周围神经缺损的可行性。方法:通过组织工程方法用PLGA导管和polyglactin 910纤维负载人胚雪旺细胞预先构置好人工神经,然后用于修复大鼠20mm的坐骨神经缺损,并与神经切断后原位缝合以及用单纯的PLGA导管进行修复的实验组进行对照。通过活体肢体功能观察、靶器官肌肉测量、电生理检测、辣根过氧化物酶示踪、连续组织切片图像分析以及透射电镜等检查神经再生情况。结果:人工神经修复组神经再生良好,效果接近于神经原位缝合组,明显优于单纯的PLGA导管修复组。结论:人胚雪旺细胞构建的人工神经可以修复20mm的周围神经缺损。  相似文献   
5.
Sciatic nerve injury and dysfunction is not an uncommon cause of lower extremity symptoms in a musculoskeletal practice. We present the case of a man who presented with lower extremity weakness, pain, and cramps, and was initially diagnosed at an outside institution with bilateral S1 radiculopathies and recommended for spine surgery. He came to us for a second opinion. Electrodiagnostic testing revealed an isolated sciatic neuropathy and the patient was referred for imaging, which showed a sciatic nerve sheath tumor. Review of the literature on sciatic neuropathies shows that there can be many possible etiologies of sciatic nerve dysfunction, but that hip arthroplasty continues to be the leading risk factor. Sciatic nerve tumors are not commonly described in the literature and their definitive management remains unclear.  相似文献   
6.
直肠癌术中保留盆腔自主神经对男性排尿及性功能的影响   总被引:5,自引:0,他引:5  
目的探讨直肠癌根治术中保留盆腔自主神经(PANP)对男性排尿及性功能的影响。方法以问卷彤式调查48例直肠癌患者PANP手术和24例非PANP手术前、后的排尿功能和性功能,比较分析行直肠癌根治术的PANP组和非PANP组患者术后排尿和性功能指标及直肠癌的局部复发率。结果PANP组患者术后排尿及性功能部分指标优于对照组(P〈0.05),两组术后局部癌肿复发率比较尤显著性差异(P〉0.05)。结论直肠癌患者根治术中实施PANP,既不增加局部癌肿复发率,还可以改善患者的排尿和性功能,提高患者的生存质量。  相似文献   
7.
Our group have studied a patient affected by a malignant schwannoma in the posterior tibial nerve. Schwannomas are uncommon neoplasms that originate from the Schwann cells of the peripheral nerves: the most common forms are benign. Malignant transformation is rarer. The therapy is surgical and the operation undertaken, if possible, should be the amputation. Alternatively, where amputation is not possible due to the specific localisation or due to patient refusal, the alternative must be the largest and most radical excision possible.  相似文献   
8.
臂丛神经卡压综合征的诊治   总被引:4,自引:0,他引:4  
目的探讨位于臂丛神经及其前中斜角肌周围的神经卡压综合征的特点及其诊治方法。方法2003年7月~2006年1月,采用门诊收集病例,根据病情轻重分组,分别采用药物、局部封闭及手术方法治疗179例确诊为臂丛神经和(或)其属支卡压综合征的患者。其中采用药物、手法治疗89例;注射治疗74例,其中需要第二次注射32例;手术治疗16例,同时或分别进行双侧手术2例,需要第二次手术者1例。结果128例患者得到1个月~2年5个月随访。其中,药物手法治疗55例,症状均有不同程度改善或能维持现状。局部注射治疗58例(其中接受第二次注射者24例),2例出现心跳减缓,其余病例无并发症发生,VAS评分情况:1分2例,2分16例,3分20例,4分12例,5分3例,6分3例,7分2例;第二次注射结果:2分5例,3分16例,4分3例。手术治疗15例,其中10例术后症状得到明显改善,恢复工作。结论臂丛神经及其属支涉及其周围众多神经,可产生众多症状;明确病因后,治疗上以保守治疗为主,效果欠佳者采用手术治疗,均可取得较好疗效。  相似文献   
9.
Selective protection of the normal host tissues from the toxic effects of anticancer agents would allow the use of higher, probably more effective, doses of the drugs. It has been demonstrated that delayed high-dose uridine administration after 5-fluorouracil decreases the extent of myelosuppression and causes faster regeneration of the bone marrow. We studied the biochemical consequences of the gastrointestinal toxicity caused by 5-fluorouracil and the potential of high-dose uridine treatment to influence these adverse effects. 5-Fluorouracil caused dose-related decreases in the biochemical parameters (thymidine kinase, sucrase, maltase, alkaline phosphatase) selected as early markers of the impaired metabolic activity of the intestinal mucosa. The nadir of the biochemical changes was reached between 24 h and 72 h after 5-fluorouracil treatment, and complete regeneration of the mucosa took 6–7 days. Delayed high-dose uridine administration failed to mitigate the severity of the gastrointestinal damage that ensued after 5-fluorouracil treatment, but caused significantly earlier regeneration of the mucosa.  相似文献   
10.
A 5-year-old boy presented with history of failure to thrive from infancy. There was a history of one sibling death due to similar problems and history of severe abortions in the mother. Routine examination of peripheral smear revealed more than 50% acanthocytes. Based on this tests were streamlined to doing lipid profile and Lipo protein electrophoresis which revealed hypolipidemia and absent Β hypo protein band. Jejuna) mucosal biopsy confirmed the diagnosis of A Beta Lipo proteinemia which revealed lipid laden enterocytes. This case illustrates the importance of simple tests like peripheral smear examination in streamlining further tests in the diagnosis of major diseases.  相似文献   
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