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101.
102.
Christopher Phillips Sarah J. Shepherd Amy Nowack Kaibao Nie Chris R.S. Kaneko Jay T. Rubinstein Leo Ling James O. Phillips 《Journal of the Association for Research in Otolaryngology》2016,17(1):19-35
Implanted vestibular neurostimulators are effective in driving slow phase eye movements in monkeys and humans. Furthermore, increases in slow phase velocity and electrically evoked compound action potential (vECAP) amplitudes occur with increasing current amplitude of electrical stimulation. In intact monkeys, protracted intermittent stimulation continues to produce robust behavioral responses and preserved vECAPs. In lesioned monkeys, shorter duration studies show preserved but with somewhat lower or higher velocity behavioral responses. It has been proposed that such changes are due to central adaptive changes in the electrically elicited vestibulo-ocular reflex (VOR). It is equally possible that these differences are due to changes in the vestibular periphery in response to activation of the vestibular efferent system. In order to investigate the site of adaptive change in response to electrical stimulation, we performed transtympanic gentamicin perfusions to induce rapid changes in vestibular input in monkeys with long-standing stably functioning vestibular neurostimulators, disambiguating the effects of implantation from the effects of ototoxic lesion. Gentamicin injection was effective in producing a large reduction in natural VOR only when it was performed in the non-implanted ear, suggesting that the implanted ear contributed little to the natural rotational response before injection. Injection of the implanted ear produced a reduction in the vECAP responses in that ear, suggesting that the intact hair cells in the non-functional ipsilateral ear were successfully lesioned by gentamicin, reducing the efficacy of stimulation in that ear. Despite this, injection of both ears produced central plastic changes that resulted in a dramatically increased slow phase velocity nystagmus elicited by electrical stimulation. These results suggest that loss of vestibular afferent activity, and a concurrent loss of electrically elicited vestibular input, produces an increase in the efficacy of a vestibular neurostimulator by eliciting centrally adapted behavioral responses without concurrent adaptive increase of galvanic afferent activation in the periphery. 相似文献
103.
Epstein-Barr virus gene polymorphism in different parts of the same nasopharyngeal carcinoma patient
Yahong Nie Yingjuan Sun Yun Wang Chengyu Liu Chengquan Zhao Bing Luo 《Archives of virology》2013,158(5):1031-1037
In most previous studies, comparisons of Epstein-Barr virus (EBV) gene polymorphisms and genotypes were made between strains from tumors and normal throat washings (TWs) from different individuals. However, it remains controversial whether different EBV subtypes are present in different parts of the same NPC patient. In order to address this question, in this study, we compared the genotypes in sets of paired throat washings (TW) and paraffin-embedded tissues of 20 patients with nasopharyngeal carcinoma (NPC), and we found the same genotype in throat washings (TWs) and tumor cells from the same individual in most cases. The subtypes of EBER and EBNA1 genes were furthermore sequenced, and identical EBV strains were identified in tumor tissues and TWs. In conclusion, different sites of the same individual are infected by the same EBV strains, except for a few differences in occasional cases, suggesting that the EBV subtype detected in throat washings is a reasonable guide to the subtype present in the carcinoma tissue. 相似文献
104.
105.
目的 建立HPLC测定人血浆中吡仑帕奈浓度的方法并考察其临床应用。方法 采用Agilent ZORBAX SB-C18(4.6 mm×150 mm,5 μm)色谱柱,流动相为0.05%磷酸(pH 3.5)-乙腈(56∶44),流速为1 mL·min–1,柱温为30℃,检测波长为290 nm。测定癫痫患儿的吡仑帕奈浓度并考察影响血药浓度的风险因素。结果 吡仑帕奈在75~2 500 μg·L–1内线性良好,定量限为75 μg·L–1,准确度不超过标示值的±10%,精密度的变异系数均≤5%,回收率为97.6%~101.0%,在实验涉及的各种条件下稳定性良好。利用该方法测定了51例癫痫患儿的吡仑帕奈血浆谷浓度,所得浓度结果为91.6~1 681.9 μg·L–1;年龄影响吡仑帕奈浓度,<5岁患者的吡仑帕奈谷浓度显著低于5~12岁患者,但与≥12岁患者无显著差异。结论 该方法操作简便,具有较高的准确性和灵敏度,能满足吡仑帕奈治疗药物监测的分析要求,年龄对吡仑帕奈的谷浓度存在显著影响。 相似文献
106.
Tian-gang Li MD Bin Ma MD Fang Nie MD Mei-juan Peng MD 《Echocardiography (Mount Kisco, N.Y.)》2020,37(7):1105-1108
Coronary artery fistula is rare in prenatal diagnosis. We have reported a case diagnosis of coronary artery fistula by using high-definition flow (HD-flow) render mode and spatiotemporal image correlation (STIC), and then evaluated the postnatal outcomes in our hospital. 相似文献
107.
目的 分析《药物分析》课程在当今药学本科教育培养过程中的现状,探索《药物分析》课程在新时代药学教育背景下的教学改革与创新,构建符合药学培养要求、满足社会市场需要的复合型药学人才培养模式。方法 第一阶段,开展教学改革的建议和需求调查;第二阶段,开展《药物分析》课程改革探索与实践;第三阶段,教学效果评价。结果 需求调查显示《药物分析》课程的教学内容、课程设计、教学手段亟须进一步优化和拓展。结论 该课程通过调整教学内容、拓展教学手段、创新多元化实践教学、融入"课程思政"建设等,激发了学生的学习兴趣和创新精神,强化了学生理论素养和实践能力,培养了其国际化视野和崇高的职业道德。 相似文献
108.
Jing Li Rui Wang Lei Yang Qi Wu Qinwan Wang Zhengchao Nie Yongchun Yu Ji Ma Qiuhui Pan 《International journal of clinical and experimental pathology》2015,8(6):6377-6386
Nestin, a member of type VI intermediate filament protein family, is widely expressed in mammalian nervous tissue and stem/precursor cells of non-neuronal normal tissues. Nestin has also been investigated to determine possible tumor-promoting functions. However, whether Nestin is involved in colorectal cancer (CRC) cells remains unclear. In this report, Nestin expression was upregulated in stromal cells of human CRC tissues. Endogenous Nestin expression in CRC cell lines SW480 and HCT116 was knocked down by a lentivirus. MTT and colony formation assays revealed that Nestin deletion significantly inhibits the proliferation of CRC cell lines; flow cytometer analysis showed that Nestin deletion causes cell cycle arrest at S phase. Transwell chamber and wound healing scratch assays also revealed that Nestin deletion suppresses cell migration. Our findings indicated that Nestin plays an essential role in CRC progression; thus, Nestin can be applied as a therapeutic target of CRC. 相似文献
109.
Teng-Fei Yu Wen He Cong-Gui Gan Ming-Chang Zhao Qiang Zhu Wei Zhang Hui Wang Yu-Kun Luo Fang Nie Li-Jun Yuan Yong Wang Yan-Li Guo Jian-Jun Yuan Li-Tao Ruan Yi-Cheng Wang Rui-Fang Zhang Hong-Xia Zhang Bin Ning Hai-Man Song Shuai Zheng Yi Li Yang Guang 《中华医学杂志(英文版)》2021,134(4):415
BackgroundThe current deep learning diagnosis of breast masses is mainly reflected by the diagnosis of benign and malignant lesions. In China, breast masses are divided into four categories according to the treatment method: inflammatory masses, adenosis, benign tumors, and malignant tumors. These categorizations are important for guiding clinical treatment. In this study, we aimed to develop a convolutional neural network (CNN) for classification of these four breast mass types using ultrasound (US) images.MethodsTaking breast biopsy or pathological examinations as the reference standard, CNNs were used to establish models for the four-way classification of 3623 breast cancer patients from 13 centers. The patients were randomly divided into training and test groups (n = 1810 vs. n = 1813). Separate models were created for two-dimensional (2D) images only, 2D and color Doppler flow imaging (2D-CDFI), and 2D-CDFI and pulsed wave Doppler (2D-CDFI-PW) images. The performance of these three models was compared using sensitivity, specificity, area under receiver operating characteristic curve (AUC), positive (PPV) and negative predictive values (NPV), positive (LR+) and negative likelihood ratios (LR−), and the performance of the 2D model was further compared between masses of different sizes with above statistical indicators, between images from different hospitals with AUC, and with the performance of 37 radiologists.ResultsThe accuracies of the 2D, 2D-CDFI, and 2D-CDFI-PW models on the test set were 87.9%, 89.2%, and 88.7%, respectively. The AUCs for classification of benign tumors, malignant tumors, inflammatory masses, and adenosis were 0.90, 0.91, 0.90, and 0.89, respectively (95% confidence intervals [CIs], 0.87–0.91, 0.89–0.92, 0.87–0.91, and 0.86–0.90). The 2D-CDFI model showed better accuracy (89.2%) on the test set than the 2D (87.9%) and 2D-CDFI-PW (88.7%) models. The 2D model showed accuracy of 81.7% on breast masses ≤1 cm and 82.3% on breast masses >1 cm; there was a significant difference between the two groups (P < 0.001). The accuracy of the CNN classifications for the test set (89.2%) was significantly higher than that of all the radiologists (30%).ConclusionsThe CNN may have high accuracy for classification of US images of breast masses and perform significantly better than human radiologists.Trial registrationChictr.org, ChiCTR1900021375; http://www.chictr.org.cn/showproj.aspx?proj=33139. 相似文献
110.
The objective of this study was to investigate the efficacy of local injection of botulinum toxin A for treating axillary osmidrosis. One hundred and fifty patients with axillary osmidrosis were randomly divided to receive botulinum toxin A injection treatment (50 U of botulinum toxin A was injected intracutaneously into 6–20 different sites within each axilla, n = 74) or surgical excision of the apocrine glands (n = 76). The patients were followed up for 1–3 months to analyze the therapeutic effect and complications of the two methods. The curative effect in patients with mild and moderate axillary osmidrosis was not significantly different between the botulinum toxin A injection group and operation group. However, for patients with severe axillary osmidrosis, surgery treatment seemed to be superior to botulinum toxin A treatment (P = 0.005). There was also no significant difference in the modified Dermatology Life Quality Index between the two treatments. Two cases showed complications related to hemorrhage and incision infection in the operation group. In conclusion, local injection of botulinum toxin A is a safe, fast and effective treatment for mild and moderate axillary osmidrosis, but the long‐term effect remains to be further investigated. 相似文献