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21.
背景 目前肺泡蛋白沉积症(PAP)的确诊需要依据支气管肺泡灌洗和/或肺活检,属于侵入性检查,而胸部CT检查对本病的诊断具有重要提示作用,尤其是胸部低剂量容积数据高分辨率CT(VHRCT)检查能更多地显示双肺解剖细节及病变细微特点,从而为临床诊断提供帮助,但鲜有这方面的报道。目的 观察低剂量VHRCT下PAP治疗前后的影像学表现,从而探讨VHRCT在PAP诊断中的临床价值。方法 回顾性分析2015年6月-2018年6月在四川大学华西第四医院诊治的24例PAP患者的临床资料和胸部低剂量VHRCT资料、确诊情况及治疗效果。结果 治疗前,24例患者双肺均可见多发的磨玻璃样密度影,边界清,边缘模糊,其中12例磨玻璃影广泛分布,呈“地图征”表现,7例患者双肺可见局限性片状实变影;6例磨玻璃影中可见小叶间隔增厚,呈“铺路石征”表现;3例可见从肺门向外放射,呈“蝶翼状”分布的大面积阴影(磨玻璃影或/和实变影);2例可见充气支气管征;部分患者双肺可见多发微小结节及间质纤维化表现;24例均未见纵隔及肺门淋巴结增大;同一患者中可有上述几种征象同时出现。治疗后复查及随访过程中,24例双肺磨玻璃影范围不同程度缩小、密度减低、边缘清晰,4例实变影密度减低呈磨玻璃密度影,2例见充气支气管征。16例经支气管肺泡灌洗确诊,3例经血清粒细胞-巨噬细胞集落刺激因子(GM-CSF)抗体检测确诊,5例经支气管镜肺穿刺活检确诊。确诊前根据患者胸部低剂量VHRCT的特征性表现高度提示PAP者共16例,符合率为66.7%(16/24),其余8例患者依据VHRCT的特征,5例提示细菌性肺炎、2例提示肺水肿、1例提示特发性肺间质纤维化。治疗后患者,呼吸困难、咳嗽等临床症状明显好转。治疗后总肺活量占预计值百分比(TLC%)、一氧化碳弥散量占预计值百分比(DLCO%)、肺活量占预计值百分比(VC%)、酸碱度(pH)、氧分压(PaO2)高于治疗前,治疗后二氧化碳分压(PaCO2)低于治疗前(P<0.05)。结论 PAP的低剂量VHRCT表现为广泛性或局限性分布的磨玻璃影和/或实变影,其中“地图征”和“铺路石征”具有一定的特征性,部分病例可见“蝶翼征”和充气支气管征;另外,本疾病一般无纵隔及肺门淋巴结增大;上述影像学征象有助于PAP的诊断、严重程度评价和疗效观察,可作为一种常规检查,推广应用。  相似文献   
22.
糖尿病属于临床高发的代谢性疾病,该疾病无法被彻底治愈,需长期通过调控机体血糖水平控制疾病,在该疾病的治疗过程中血糖的监测属于重中之重的措施,随着医疗技术的不断发展、完善,临床现推出一种血糖监测系统为动态血糖监测系统,可对血糖全天的动态变化进行监测,显著规避了传统监测方式间断性的缺点,对疾病治疗效果以及患者机体代谢控制情给予更客观的评价,特别是对于突发的餐后高血糖以及低血糖等并发症给予有效监测。现为探究将其应用于临床实践操作中的具体价值,本文从将该检测方式应用至临床治疗中的效果方面展开论述,为具体实施效果提供参考。  相似文献   
23.
《Journal of endodontics》2020,46(8):1125-1129
IntroductionThe aim of this study was to compare the buckling resistance of nickel-titanium (NiTi) instruments for glide path preparation depending on the test mode (static vs dynamic).MethodsThe conventional PathFile (PF; Dentsply Sirona, Ballaigues, Switzerland) and heat-treated ProGlider (PG, Dentsply Sirona) and WaveOne Gold Glider (WG, Dentsply Sirona) were evaluated. The instrument tips were placed in a small dimple prepared in an aluminum cube in a customized device. The file was then pushed in the axial direction at a 1.0-mm/s crosshead speed with rotation (dynamic mode) or without rotation (static mode). The dynamic mode of WG used its dedicated reciprocating rotation, whereas the others were rotated continuously at 300 rpm. The axial load and lateral buckling displacement were simultaneously measured. Data were analyzed statistically using 2-way analysis of variance (P = .05).ResultsThe buckling resistance in the dynamic mode was higher than in the static mode for PG and WG (P < .05), whereas PF was not influenced by test modes (P > .05). In the dynamic mode, the PG required the highest buckling load followed by PF and WG (P < .05). In the static mode, the WG showed the lowest load (P < .05). The dynamic mode showed significantly more upper level lateral buckling displacement than in the static mode (P < .05).ConclusionsWhen the glide path preparation instruments moved in the dynamic mode as in clinical situations, the buckling resistance of the heat-treated NiTi glide path instruments was higher than in the static condition. The heat-treated instruments may have better buckling resistance than the conventional NiTi instrument in clinical situations.  相似文献   
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Tissue characterization in brain tumors and, in particular, in high‐grade gliomas is challenging as a result of the co‐existence of several intra‐tumoral tissue types within the same region and the high spatial heterogeneity. This study presents a method for the detection of the relevant tumor substructures (i.e. viable tumor, necrosis and edema), which could be of added value for the diagnosis, treatment planning and follow‐up of individual patients. Twenty‐four patients with glioma [10 low‐grade gliomas (LGGs), 14 high‐grade gliomas (HGGs)] underwent a multi‐parametric MRI (MP‐MRI) scheme, including conventional MRI (cMRI), perfusion‐weighted imaging (PWI), diffusion kurtosis imaging (DKI) and short‐TE 1H MRSI. MP‐MRI parameters were derived: T2, T1 + contrast, fluid‐attenuated inversion recovery (FLAIR), relative cerebral blood volume (rCBV), mean diffusivity (MD), fractional anisotropy (FA), mean kurtosis (MK) and the principal metabolites lipids (Lip), lactate (Lac), N‐acetyl‐aspartate (NAA), total choline (Cho), etc. Hierarchical non‐negative matrix factorization (hNMF) was applied to the MP‐MRI parameters, providing tissue characterization on a patient‐by‐patient and voxel‐by‐voxel basis. Tissue‐specific patterns were obtained and the spatial distribution of each tissue type was visualized by means of abundance maps. Dice scores were calculated by comparing tissue segmentation derived from hNMF with the manual segmentation by a radiologist. Correlation coefficients were calculated between each pathologic tissue source and the average feature vector within the corresponding tissue region. For the patients with HGG, mean Dice scores of 78%, 85% and 83% were obtained for viable tumor, the tumor core and the complete tumor region. The mean correlation coefficients were 0.91 for tumor, 0.97 for necrosis and 0.96 for edema. For the patients with LGG, a mean Dice score of 85% and mean correlation coefficient of 0.95 were found for the tumor region. hNMF was also applied to reduced MRI datasets, showing the added value of individual MRI modalities. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
27.
Dry powder inhalers (DPIs) are gaining popularity for the delivery of drugs. A cost effective and efficient delivery device is necessary. Developing new DPIs by modifying an existing device may be the simplest way to improve the performance of the devices. The aim of this research was to produce a new DPIs using computational fluid dynamics (CFD). The new DPIs took advantages of the Cyclohaler® and the Rotahaler®. We chose a combination of the capsule chamber of the Cyclohaler® and the mouthpiece and grid of the Rotahaler®. Computer-aided design models of the devices were created and evaluated using CFD. Prototype models were created and tested with the DPI dispersion experiments. The proposed model 3 device had a high turbulence with a good degree of deagglomeration in the CFD and the experiment data. The %fine particle fraction (FPF) was around 50% at 60?L/min. The mass median aerodynamic diameter was around 2.8–4?μm. The FPF were strongly correlated to the CFD-predicted turbulence and the mechanical impaction parameters. The drug retention in the capsule was only 5–7%. In summary, a simple modification of the Cyclohaler® and Rotahaler® could produce a better performing inhaler using the CFD-assisted design.  相似文献   
28.
目的探讨磁共振结合高分辨率CT在中耳乳突炎患者术前评估中的临床应用。方法选取我院2018年11月~2020年12月接收患有中耳乳突炎的患者40例为研究对象,所有患者均采用磁共振以及高分辨率CT进行诊断检查,比较两组患者诊断后手术特征显示度。结果诊断后,磁共振联合高分辨率CT检查图像显示度高于单独使用磁共振或高分辨率CT诊断(P<0.05)。结论使用磁共振结合高分辨率CT对中耳乳突炎患者进行术前评估,显示度较高,提高诊断准确度,值得推广。  相似文献   
29.
目的观察iPro2回顾式动态血糖监测优化2型糖尿病预混胰岛素的治疗效果。方法选取40例应用预混胰岛素的患者,随机分为观察组、对照组各20例,对照组在常规SMBG基础上行糖尿病教育,观察组应用美国美敦力公司生产的iPro2回顾式动态血糖监测系统对患者进行个体化糖尿病教育,并观察两组空腹血糖(FBG)、餐后2 h血糖(2 h PG)、糖化血红蛋白(HbA1c)及观察组干预前后平均血糖(MBG)、标准差(SDBG)。结果干预后,两组各指标均明显下降,差异具有统计学意义,P<0.05;与对照组相比,干预后观察组餐后2 h血糖(2 h PG)、MBG、SDBG下降更明显,差异有统计学意义,P<0.05。结论采用iPro2回顾式动态血糖监测指导应用预混胰岛素2型糖尿病患者进行个体化糖尿病教育,优化生活方式,能显著降低患者餐后血糖、平均血糖及血糖波动。  相似文献   
30.
Human immunodeficiency virus/acquired immune deficiency syndrome (HIV/AIDS) is one of the leading causes of morbidity and mortality in West Africa. Prevalence among the most productive age group in West and Central Africa stood at 1.5%, 3.4.0%, 2.5%, and 2.1% in 1990, 2000, 2010, and 2015 respectively. This study examined the effect of HIV/AIDS on economic growth in West Africa with focus on 11 countries. The augmented Solow model, rooted in the neoclassical growth theory, was used, which was operationalized using dynamic panel data modeling approach. Incidence, prevalence, number of people living with HIV/AIDS (PLWHA), and AIDS‐related deaths were used to measure HIV/AIDS. Estimations using system GMM returned statistically significant results while those of first difference and difference GMM were not. From the outcome of system GMM analysis, a percentage increase in incidence, prevalence, PLWHA, and AIDS deaths correspondingly reduced growth significantly through their effects on life expectancy by 0.15%, 0.02%, 0.004%, and 0.03%. Acquired immune deficiency syndrome deaths and PLWHA lowered economic growth through enrolment but not significantly. The import of the findings is that HIV/AIDS threatens growth through life expectancy in West Africa. Therefore, its spread in the subregion should be effectively contained while proper treatment should be provided for all infected persons.  相似文献   
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