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991.
992.
目的 探究鼻内镜术后联合置管冲洗治疗真菌性上颌窦炎安全性和临床效果。方法 选择2013年3月~2017年3月我院用鼻内镜术后行鼻腔冲洗的真菌性上颌窦炎患者840例,随机分为实验组440例和对照组400例。实验组术后配合常规治疗的同时给予生理盐水500 ml置管冲洗术腔,1次/d,持续14 d;对照组则在术后配合常规治疗的同时给予生理盐水500 ml常规冲洗术腔,1次/d,持续14 d。比较两组患者鼻内镜术后1月、2月、3月及6月鼻腔恢复情况。结果 实验组术后第1、2、3及6月痊愈率与对照组比较,差异有统计学意义(P<0.05),第6月实验组痊愈率为45.45%,显著高于对照组的27.50%,差异有统计意义(P<0.05)。结论 真菌性上颌窦炎患者在鼻内镜手术术后,采用常规综合治疗配合置管冲洗术腔,能够很好地把术腔分泌物及痂皮冲出,减轻鼻腔、鼻窦的炎性反应,缩短鼻窦上皮化的时间,恢复保护和防御功能。 相似文献
993.
针对脑机接口系统中P300电位识别正确率不高的问题,提出一种基于改进卷积神经网络的P300事件相关电位分类识别方法。通过将传统卷积神经网络中第二个串行连接的卷积层改为3个并行连接的卷积层,可加大网络宽度,提升网络对P300信号特征提取的能力;将提取的特征经全互连层组合后,采用sigmoid函数构建P300事件相关电位分类器。针对脑机接口竞赛数据中靶刺激与非靶刺激数据量不平衡的问题,采用过抽样方式,对含有P300事件相关电位的脑电数据做部分平均来增加数据量,其训练集和测试集样本量分别为25 500和18 000。采用Adam优化方法,有监督地训练这种改进的卷积神经网络。结果表明,相比传统的卷积神经网络,该方法在实验次数大于11次时,字符识别正确率均高于95%,这对于脑机接口的应用具有重要的意义。 相似文献
994.
利用亮甲酚蓝染色筛选优质猪卵母细胞 总被引:3,自引:0,他引:3
目的 利用亮甲酚蓝(BCB)染色提高猪体外胚胎培养体系的效率.方法 对猪卵丘卵母细胞复合体(COCs)进行BCB染色,观察染色后猪卵母细胞成熟率和早期胚胎发育能力并进行分析. 结果 着色组(BCB+)猪卵母细胞达到减数分裂Ⅱ(MⅡ)期的比率(91.6%)显著高于未着色组(BCB-)(64.0%)和对照组猪卵母细胞(77.5%)(P<0.05);BCB+孤雌猪胚胎的囊胚率(34.9%)显著高于BCB-(9.5%)和对照组(23.1%)(P<0.05);BCB+核移植猪胚胎的囊胚率(23.0%)显著高于BCB-(5.0%)和对照组(14.1%)(P<0.05).结论 BCB染色是一种有效筛选具有较强发育能力猪卵母细胞的方法. 相似文献
995.
Yangyang Yao Zhen Liu Hui Guo Shanshan Huang Min Zhong Jun Deng Jianping Xiong 《Pathology, research and practice》2018,214(12):2062-2068
The gene TRIM23 (tripartite motif containing 23) is a member of the tripartite motif (TRIM) family whose expression putatively participates in many pathophysiological processes. Nonetheless, the role of TRIM23 in gastric cancer (GC) remains uncertain. Our study evaluated the expression of TRIM23 in GC tissues and cell lines, and investigated an association between TRIM23 and survival. In the present study, our results demonstrated that TRIM23 mRNA and protein were frequently over-expressed in GC cell lines and GC tissues. High level of TRIM23 protein correlated with tumor size, tumor-node-metastasis (TNM) stage, depth of invasion, lymph node metastasis (LNM), tumor differentiation, and nerve invasion. Compared with the low TRIM23 protein group, the high TRIM23 protein group was significantly associated with worse prognosis of GC patients. Consistently, the KM-plot database suggested that high TRIM23 mRNA expression was also linked to a poor prognosis in GC patients both in positive and negative subgroups of human epidermal growth factor receptor 2 (HER2). But in the HER2 positive subgroup, the advantages of the low TRIM23 expression on overall survival were much more statistically significant. The univariate analysis indicated that TRIM23 expression correlated with overall survival. The multivariate analysis showed that independent factors of prognosis in GC were lymph node metastasis, vascular invasion, and depth of invasion. In summary, TRIM23 may be associated with progression of GC, and may be considered a therapeutic target for GC patients. 相似文献
996.
Yun Chen YiPing Zhong HaiBo Zhou ShanMing Zhang QianBao Tan Wei Fan 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2014,232(3):985-994
We investigated the processing of self-related information under the prime paradigm using event-related potentials (ERPs) to provide evidence for implicit self-positivity bias in Chinese individuals. Reaction times and ERPs were recorded when participants made positive/negative emotional judgments to personality-trait adjectives about themselves or others. Faster responses occurred to self-related positive adjectives and other-related negative adjectives, indicating implicit self-positivity bias at the behavioral level. ERPs showed an interaction between prime and emotion at the P300 amplitude, with larger P300 amplitudes for words within the self-positivity bias, indicating that self-related information occupied more attentional resources. Larger N400 amplitudes elicited by words that were inconsistent with the self-positivity bias, suggesting that accessing non-self-relevant information is more difficult than self-relevant information. Thus, P300 and N400 could be used as neuro-indexes of the implicit self-positivity bias. 相似文献
997.
【摘 要】 目的:为解决第三代血泵中磁力和液力悬浮系统体积偏大、发热多、水力性能差、血损严重等问题,提出一种磁液双悬浮支承系统。 方法:磁液双悬浮支承系统轴向靠磁力、径向靠径向液力共同实现转子的稳定悬浮;分别利用ANSYS电磁模块和楔形动压承载原理对轴向磁力、径向液力进行分析,利用Fluent对磁液双悬轴流血泵的水力性能进行仿真分析。 结果:对悬浮系统轴向、径向承载力的分析以及悬浮实验结果表明该系统可以实现稳定的悬浮;Fluent仿真及水力实验表明当血泵转子转速为9 500 r/min以上时,能满足人体需要。 结论:磁液双悬浮支承系统具有较好的悬浮性、水力性能,可作为第三代血泵进一步改进的选择方向。 相似文献
998.
Association between left atrial enlargement and obstructive sleep apnea in a general population of 71‐year‐old men 下载免费PDF全文
Henrik Holtstrand Hjälm Michael Fu Per‐Olof Hansson You Zhong Kenneth Caidahl Zacharias Mandalenakis David Morales Constantinos Ergatoudes Annika Rosengren Ludger Grote Erik Thunström 《Journal of sleep research》2018,27(2):254-260
Left atrial enlargement has been shown to be associated with obstructive sleep apnea in patients with coronary artery disease and in sleep clinic cohorts. However, data from the general population are limited. The aim of this study was to investigate whether there is an association between obstructive sleep apnea and left atrial enlargement in a random sample from a general population of 71‐year‐old men. As part of the longitudinal population study The Study of Men Born in 1943, we analysed cross‐sectional data for 411 men, all 71 years old, who had participated in an overnight home sleep study and a standardized echocardiographic examination. Of the 411 men, 29.4% had moderate to severe obstructive sleep apnea [apnea–hypopnea index score of ≥15 (n = 121)]. These participants showed a significantly higher frequency of systolic heart failure, hypertension, overweight, had greater waist circumference as well as higher left atrial areas compared with men with no or mild obstructive sleep apnea (23.7 ± 5.5 cm2 versus 21.6 ± 4.5 cm2, P < 0.001). In a linear regression analysis, obstructive sleep apnea was significantly associated with left atrial enlargement after adjusting for overweight, atrial fibrillation, heart failure with reduced ejection fraction, hypertension and mitral regurgitation. Compared with individuals without obstructive sleep apnea, the mean left atrial area was 1.7 ± 1.5 cm2 larger in men with severe obstructive sleep apnea (P < 0.05) and 1.3 ± 1.1 cm2 larger among men with moderate obstructive sleep apnea (P < 0.05). In this cross‐sectional study of 71‐year‐old men from the general population, left atrial area was independently associated with prevalence and severity of obstructive sleep apnea. 相似文献
999.
Biodegradable polyanhydrides possess unique features like those that they can predominantly undergo surface erosion, and the payloads can be released by a steady speed. However, there is little work that has been published to describe the polyanhydride micelles with redox-responsiveness as a nanocarrier for drug delivery. In this study, we develop one type of new amphiphilic polyanhydride copolymer containing disulfide bonds between the hydrophilic and hydrophobic segments. The copolymer can self-assemble into stable micelles with well-defined core–shell structure and a uniform size distribution with an average diameter of 69 nm. The disassembly behaviors of the micelles triggered by glutathione are evaluated from the changes of the micellar size, morphology and molecular weight. An approximate zero-order in vitro drug release mode with a fast speed can be achieved in a reducing and acid environment similar with that of tumor cells. In vitro cytotoxicity analysis demonstrate that the Cur-loaded micelles are of great efficiency in inhibiting the growth of cancer cells due to the rapidly intracellular delivery of therapeutic agent. Both the qualitative and quantitative results of the antitumor activity in 4T1 tumor-bearing BALB/c mice reveal that the redox-responsive micelles have a more significant therapeutic effect to artificial solid tumor compared to the redox-insensitive micelles. This study provides a new insight into the biomedical application of polyanhydrides in drug delivery. 相似文献
1000.
Jing Liu Shengping Zhong Hualin Lan Xu Meng Haibo Zhang Yubo Fan Yuxing Wang Chunren Wang Zhaoxu Wang 《Biomaterials》2014
The calcification initiation and progression of bioprosthetic heart valve were investigated in a rat model by enhanced micro-computed tomography, together with histologic study and scanning electron microscope analysis. The implantation data at early stage showed apparent dendritic patterns in the radiographic images for the glutaraldehyde-treated bovine pericardium and this dendritic pattern was verified to be associated with the vessel distribution in the tissue. Histologic study and scanning electron microscope analysis both indicated that the calcium deposits in the pericardium vessels regions were more grievous than those scattered in the collagen fibers in the first two weeks after implantation. Subsequently, calcification spreaded and the entire sample was severely calcified in 60 days. 相似文献