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21.
目的 探讨不同年龄阿尔茨海默病(AD)患者ADC值与年龄的相关性。方法 选取30例AD患者(AD组)和年龄与之相匹配的30名志愿者(对照组),按年龄段各分为6个亚组[55~59岁(n=3)、60~64岁(n=4)、65~70岁(n=9)、71~74岁(n=5)、75~80岁(n=6)、>80岁(n=3)],测量双侧海马、红核、尾状核、杏仁体、壳核ADC值,并进行配对t检验、独立样本t检验、单因素方差分析及Pearson相关分析。结果 AD组红核左、右侧ADC值有统计学差异(P=0.022)。AD组不同年龄亚组右侧海马、双侧尾状核、右侧壳核ADC值差异有统计学意义(P均<0.05);2组不同年龄亚组双侧海马、壳核、尾状核ADC值差异有统计学意义(P均<0.05)。AD组右侧海马(r=0.615,P<0.001)、右侧壳核(r=0.653,P=0.001)及双侧尾状核(左侧:r=0.397,P=0.030;右侧:r=0.429,P=0.020)ADC值与年龄呈正相关。结论 AD患者右侧海马和壳核、双侧尾状核ADC值随年龄增加而增大。ADC值可为临床预测和早期诊断AD脑内右侧海马和壳核、双侧尾状核神经退行性病变提供参考。  相似文献   
22.
良性前列腺增生(BPH)是老年男性常见的泌尿系统疾病,其发病与前列腺慢性炎症之间存在显著相关。感染因子、尿液返流、代谢综合征、衰老过程和自身免疫应答在内的几种刺激,通过相应分子途径引起前列腺免疫细胞的组织定位和组成成分发生广泛改变,从而导致免疫系统失调,之后引发的组织损伤和缓慢愈合,导致了BPH发生和进展。本文通过总结良性前列腺增生与前列腺慢性炎症的相关性的临床研究结果,前列腺免疫细胞在病理生理机制层面与前两者之间的内在联系,以及抗炎药物对BPH-LUTS的干预作用,以其为BPH-LUTS的药物研发提供参考。  相似文献   
23.
健康状态的辨识是把握健康的前提。当前学界已存在专家辨识模式、标准辨识模式、数字辨识模式、智能辨识模式以及微观辨识模式等。联合多种辨识方法,构建健康状态辨识体系,形成常态与动态结合、主观与客观结合、人机互参的中医健康状态个体化辨识方法是研究的趋势所在。文章对未来的研究方向进行展望,探讨了多元辨识模式、远程辨识模式、终身辨识模式、自动辨识模式的思路方法,以期促进全民健康事业,助力"健康中国"战略。  相似文献   
24.
目的 探讨不同非密闭雾化方式在不合作患儿接受布地奈德雾化治疗中的应用效果。方法 选取本院门诊270例3岁以下使用布地奈德雾化治疗的患儿,采用随机数字表法将患儿分为Pari雾化系统、Philips雾化系统及Salter雾化系统3个治疗组,毎组90例,各组又依据面罩距离面部0 cm、2 cm、4 cm分为3个小组,毎组30例,分别测量各组雾化气流流速及吸入雾化颗粒量占总雾化颗粒量的比例。采用方差分析及Bonferroni进行统计分析。结果 雾化气流流速及雾化吸入量在不同雾化系统组间差异有统计学意义(P<0.05)。在3种距离下,Pari系统均能使患儿吸入最多量的雾化颗粒,其次是Salter系统,再是Philips系统,与此相反,气流流速Pari系统最低。Pari系统离开面部4 cm及Salter系统离开面部2 cm的吸入量均高于Philips系统0 cm的吸入量。结论 选择合适的非密闭雾化系统方式,是提高不合作患儿布地奈德雾化治疗的有效方式。  相似文献   
25.
当代社会,老年人口比例呈现不断上升的趋势,老龄化问题日益严峻。因此,如何有效地延缓衰老不仅成为了世界医学研究的热点,也成为了全球亟待解决的问题。中医药在延缓衰老方面经验丰富,而滋阴药在此类研究中效果显著。本文通过整理滋阴药抗衰老作用机制的若干文献,对滋阴复方六味地黄丸、二至丸、左归丸及其他滋阴中药延缓衰老的机制研究进展进行综述。  相似文献   
26.
BACKGROUND AND PURPOSE:Accurate and reliable detection of white matter hyperintensities and their volume quantification can provide valuable clinical information to assess neurologic disease progression. In this work, a stacked generalization ensemble of orthogonal 3D convolutional neural networks, StackGen-Net, is explored for improving automated detection of white matter hyperintensities in 3D T2-FLAIR images.MATERIALS AND METHODS:Individual convolutional neural networks in StackGen-Net were trained on 2.5D patches from orthogonal reformatting of 3D-FLAIR (n = 21) to yield white matter hyperintensity posteriors. A meta convolutional neural network was trained to learn the functional mapping from orthogonal white matter hyperintensity posteriors to the final white matter hyperintensity prediction. The impact of training data and architecture choices on white matter hyperintensity segmentation performance was systematically evaluated on a test cohort (n = 9). The segmentation performance of StackGen-Net was compared with state-of-the-art convolutional neural network techniques on an independent test cohort from the Alzheimer’s Disease Neuroimaging Initiative-3 (n = 20).RESULTS:StackGen-Net outperformed individual convolutional neural networks in the ensemble and their combination using averaging or majority voting. In a comparison with state-of-the-art white matter hyperintensity segmentation techniques, StackGen-Net achieved a significantly higher Dice score (0.76 [SD, 0.08], F1-lesion (0.74 [SD, 0.13]), and area under precision-recall curve (0.84 [SD, 0.09]), and the lowest absolute volume difference (13.3% [SD, 9.1%]). StackGen-Net performance in Dice scores (median = 0.74) did not significantly differ (P = .22) from interobserver (median = 0.73) variability between 2 experienced neuroradiologists. We found no significant difference (P = .15) in white matter hyperintensity lesion volumes from StackGen-Net predictions and ground truth annotations.CONCLUSIONS:A stacked generalization of convolutional neural networks, utilizing multiplanar lesion information using 2.5D spatial context, greatly improved the segmentation performance of StackGen-Net compared with traditional ensemble techniques and some state-of-the-art deep learning models for 3D-FLAIR.

White matter hyperintensities (WMHs) correspond to pathologic features of axonal degeneration, demyelination, and gliosis observed within cerebral white matter.1 Clinically, the extent of WMHs in the brain has been associated with cognitive impairment, Alzheimer’s disease and vascular dementia, and increased risk of stroke.2,3 The detection and quantification of WMH volumes to monitor lesion burden evolution and its correlation with clinical outcomes have been of interest in clinical research.4,5 Although the extent of WMHs can be visually scored,6 the categoric nature of such scoring systems makes quantitative evaluation of disease progression difficult. Manually segmenting WMHs is tedious, prone to inter- and intraobserver variability, and is, in most cases, impractical. Thus, there is an increased interest in developing fast, accurate, and reliable computer-aided automated techniques for WMH segmentation.Convolutional neural network (CNN)-based approaches have been successful in several semantic segmentation tasks in medical imaging.7 Recent works have proposed using deep learning–based methods for segmenting WMHs using 2D-FLAIR images.8-11 More recently, a WMH segmentation challenge12 was also organized (http://wmh.isi.uu.nl/) to facilitate comparison of automated segmentation of WMHs of presumed vascular origin in 2D multislice T2-FLAIR images. Architectures that used an ensemble of separately trained CNNs showed promising results in this challenge, with 3 of the top 5 winners using ensemble-based techniques.12Conventional 2D-FLAIR images are typically acquired with thick slices (3–4 mm) and possible slice gaps. Partial volume effects from a thick slice are likely to affect the detection of smaller lesions, both in-plane and out-of-plane. 3D-FLAIR images, with isotropic resolution, have been shown to achieve higher resolution and contrast-to-noise ratio13 and have shown promising results in MS lesion detection using 3D CNNs.14 Additionally, the isotropic resolution enables viewing and evaluation of the images in multiple planes. This multiplanar reformatting of 3D-FLAIR without the use of interpolating kernels is only possible due to the isotropic nature of the acquisition. Network architectures that use information from the 3 orthogonal views have been explored in recent works for CNN-based segmentation of 3D MR imaging data.15 The use of data from multiple planes allows more spatial context during training without the computational burden associated with full 3D training.16 The use of 3 orthogonal views simultaneously mirrors how humans approach this segmentation task.Ensembles of CNNs have been shown to average away the variances in the solution and the choice of model- and configuration-specific behaviors of CNNs.17 Traditionally, the solutions from these separately trained CNNs are combined by averaging or using a majority consensus. In this work, we propose the use of a stacked generalization framework (StackGen-Net) for combining multiplanar lesion information from 3D CNN ensembles to improve the detection of WMH lesions in 3D-FLAIR. A stacked generalization18 framework learns to combine solutions from individual CNNs in the ensemble. We systematically evaluated the performance of this framework and compared it with traditional ensemble techniques, such as averaging or majority voting, and state-of-the-art deep learning techniques.  相似文献   
27.
目的 总结国产封堵器经皮和经胸途径治疗先天性心脏病的临床疗效。方法 回顾性分析我院2013年1月至2017年12月在X线透视下或单纯超声心动图引导下采用经皮穿刺股静脉或股动静脉法,或者食管超声心动图监测下经胸小切口行先天性心脏病封堵1186例,其中经皮X线下封堵1081例、经皮单纯超声引导下封堵42例、经胸封堵63例;其中动脉导管未闭( patent ductus arteriole,PDA)426例、房间隔缺损(atrial septal defect,ASD)363例、室间隔缺损(ventricular septal defect,VSD)348例、卵圆孔未闭11例、房间隔缺损合并室间隔缺损9例、房间隔缺损合并动脉导管未闭6例、房间隔缺损合并肺动脉瓣狭窄(pulmonary stenosis,PS)12例、动脉导管未闭合并肺动脉瓣狭窄8例、主肺动脉侧支封堵3例[经胸封堵66例改为63例,PDA443例改为426例]。结果 全组病例成功率98.2%(1165/1186),无死亡病例。随访1~36个月,术后第1、3、6、12个月及术后每年常规行超声心动图及心电图检查。术后第1、6、12个月的随访率分别为 92.9%(1102/1186)、84.1%(998/1186)、70.5%(836/1186)。超声心动图提示少量残余分流(<3 mm)18例;三尖瓣少量反流33例,中量反流5例;主动脉瓣轻度反流5例,中度反流1例;心律失常Ⅲ°房室传导阻滞(Avionics Bulletin,AVB[房室传导阻滞(Avionics Bulletin,AVB)])1 例,Ⅱ°AVB 3例,完全性左束支3例,交界性心动过速3例,交界性逸搏2例。结论 国产封堵器在先天性心脏病封堵治疗中具有成功率高、创伤小、并发症低、操作容易、疗效确切、恢复快等特点,是治疗先天性心脏病的理想方法。  相似文献   
28.
Objective: To assess the effect of electroacupuncture(EA) on expression of cytoskeletal proteins from Sertoli cells(SCs) and spermatogenesis in rats with oligozoospermia of insufficiency of Shen(Kidney)essence syndrome(OIKES).Methods: Twenty healthy male Sprague-Dawley rats were randomly assigned to four groups using a random number table: control,tripterygium glycosides(TG) treatment,sham and EA groups(n=5 in each group).A rat model of OIKES was established by oral gavage with TG.The EA group was treated with TG and received EA at Shenshu(BL 23) and Zusanli(ST 36) acupoints for 20 min,once daily for 30 days,while the sham group received EA at identical acupoints with skin penetration without stimulation.After 30 days,the ?nal body weight and coef?cients for the testis and epididymis were calculated and sperm parameters were measured.Immunohistochemical analyses were performed to detect expression of vimentin and α-tubulin in SCs and proliferating cell nuclear antigen(PCNA) immunoreactivity in germ cells.Apoptosis in germ cells was quanti?ed by the transferase biotin-dUTP nick end labeling assay.Results: Compared with the control group,the final body weight and testis/epididymis coefficients of rats in the TG-treated group were not significantly different,but the sperm count and motility were lower(P0.05).Expressions of vimentin and α-tubulin were also signi?cantly weaker(P0.01).The PCNA immunoreactivity of germ cells was decreased(P=0.059),whereas the apoptotic index of germ cells was increased signi?cantly(P0.01).In contrast,EA at BL 23 and ST 36 acupoints signi?cantly improved the ?nal body weight as well as the sperm count,concentration and motility(P0.01 or P0.05).EA increased expression of vimentin and α-tubulin in SCs markedly,and signi?cantly enhanced PCNA immunoreactivity with decreased apoptosis in germ cells(P0.01 or P0.05).Conclusions: EA at BL 23 and ST 36 acupoints has protective effects on spermatogenesis in rats with OIKES.This effect seems to be achieved by attenuating TG-induced disruption of cytoskeletal protein in SCs.  相似文献   
29.
当前,体外受精-胚胎移植技术(in vito fertilization,IVF-ET)是治疗不孕不育问题的重要手段之一。1978年世界上第一例试管婴儿自英国诞生以来,已有成千上万的不孕不育夫妇通过这项技术获得了后代,随这项技术的发展,促排卵技术、配子的体外受精技术、胚胎的体外培养技术不断得到改善,但目前仍有许多夫妇因为各种原因导致不能受孕,受精失败就是原因之一。有文献指出:夫妇双方在排除男性不育的因素之后,传统IVF-ET的受精失败率仍然在2-3%[1],受精失败的模式包括:卵子完全不受精及卵子的异常受精。临床上卵子完全不受精或受精率低时,可以通过补救ICSI来进行挽救,但卵子异常受精情况的发生目前还无法进行挽救,这导致卵子的利用率低下,增加了患者的经济与精神负担。因此,如何预防和降低异常受精的发生将成为改善IVF-ET总体结局的重要环节,本文拟将体外受精过程中出现的可能影响受精结局的问题进行逐一探讨。  相似文献   
30.
新型冠状病毒肺炎中医认识初探   总被引:6,自引:2,他引:4       下载免费PDF全文
王刚  金劲松 《天津中医药》2020,37(3):247-250
新型冠状病毒肺炎中医属"寒湿疫"范畴,以湿邪为病机核心,以肺为病位中心,以脾胃盛衰为疾病进退的关键。治疗与预防调护方面,急性期,卫气同调,宜宣清和化;恢复期,肺脾同治,宜清补轻宣,注重饮食、情志调摄;谨慎使用抗病毒、抗生素、激素及液体疗法。  相似文献   
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