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现有的非接触式心率检测方法存在噪声干扰、准确率低等问题。针对这些问题,提出一种基于FastICA与改进的自适应噪声完全集合经验模态分解(ICEEMDAN)相结合的算法,采用人脸视频进行心率检测。用摄像头采集人脸视频,并从视频中提取R、G、B通道源信号,即皮肤颜色变化信号,分别求出RGB这3个颜色通道的像素平均值;然后利用 FastICA对RGB这3组像素平均值进行解混,得到3组独立源信号,再用ICEEMDAN将其中一组独立源信号进行模态分解,并选取合适频段内的固有模式函数(IMF)估计心率的信号,最后用频谱分析计算得到心率。设计实验对8名人员进行了人脸视频检测,将检测结果与多参数监护仪进行对比分析。实验结果表明,该方法与多参数监护仪测量结果的平均误差与均方根误差均小于1 beat/min,因此基于FastICA与ICEEMDAN的人脸视频心率检测对人体心率检测具有良好的稳定性和准确性。  相似文献   
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目的:评价快速康复(fast track,FT)模式在不同方式胃癌根治手术患者术后康复中的有效性及安全性。方法:收集我科2016年1月至2017年6月期间行开放(OS)及腹腔镜(LS)胃癌根治手术患者各40例,随机分为FT处理组(OS+FT组、LS+FT组)和常规处理(NT)对照组(OS+NT组、LS+NT组),比较不同处理模式对术后疼痛评分、恢复情况和术后并发症发生率的影响。结果:OS+FT组、LS+FT组术后1、2、3、4和5 d疼痛评分均低于NT对照组,各观察时点差异均有统计学意义(P<0.005);OS+FT组、LS+FT组术后首次排气时间、首次离床时间以及住院时间均短于NT对照组(P<0.05);术后OS+FT组、LS+FT组总体并发症发生率均为10%,与NT对照组(OS+NT组20%,LS+NT组15%)相比,差异无统计学意义(P>0.05)。结论:FT模式有利于减少患者痛苦,加速术后恢复,未增加术后并发症风险,在不同方式胃切除手术患者围术期处理过程中安全、有效。  相似文献   
4.
PurposeThe purpose of this study was to compare morphologic assessment and relaxometry of patellar hyaline cartilage between conventional sequences (fast spin-echo [FSE] T2-weighted fat-saturated and T2-mapping) and synthetic T2 short-TI inversion recovery (STIR) and T2 maps at 1.5 T magnetic resonance imaging (MRI).MethodThe MRI examinations of the knee obtained at 1.5 T in 49 consecutive patients were retrospectively studied. There were 21 men and 28 women with a mean age of 45 ± 17.7 (SD) years (range: 18–88 years). Conventional and synthetic acquisitions were performed, including T2-weighted fat-saturated and T2-mapping sequences. Two radiologists independently compared patellar cartilage T2-relaxation time on conventional T2-mapping and synthetic T2-mapping images. A third radiologist evaluated the patellar cartilage morphology on conventional and synthetic T2-weighted images. The presence of artifacts was also assessed. Interobserver agreement for quantitative variables was assessed using intraclass correlation coefficient (ICC).ResultsIn vitro, conventional and synthetic T2 maps yielded similar mean T2 values 58.5 ± 2.3 (SD) ms and 58.8 ± 2.6 (SD) ms, respectively (P = 0.414) and 6% lower than the expected experimental values (P = 0.038). Synthetic images allowed for a 15% reduction in examination time compared to conventional images. On conventional sequences, patellar chondropathy was identified in 35 patients (35/49; 71%) with a mean chondropathy grade of 4.8 ± 4.8 (SD). On synthetic images, 28 patients (28/49; 57%) were diagnosed with patellar chondropathy, with a significant 14% difference (P = 0.009) and lower chondropathy scores (3.7 ± 4.9 [SD]) compared to conventional images. Motion artifacts were more frequently observed on synthetic images (18%) than on conventional ones (6%). The interobserver agreement was excellent for both conventional and synthetic T2 maps (ICC > 0.83). Mean cartilage T2 values were significantly greater on synthetic images (36.2 ± 3.8 [SD] ms; range: 29-46 ms) relative to conventional T2 maps (31.8 ± 4.1 [SD] ms; range: 26-49 ms) (P < 0.0001).ConclusionDespite a decrease in examination duration, synthetic images convey lower diagnostic performance for chondropathy, greater prevalence of motion artifacts, and an overestimation of T2 values compared to conventional MRI sequences.  相似文献   
5.
Nocardiosis is primarily a pulmonary infection commonly seen in immunocompromised individuals. However, lymphocutaneous nocardiosis is observed in immunocompetent individuals often after trauma. The clinical and cytomorphological features of lymphocutaneous nocardiosis closely mimic the most common infections in India such as tuberculosis and mycetoma (very common cutaneous infection with discharging sinus). As it is crucial to differentiate nocardiosis from tuberculosis, to avoid unnecessary antitubercular treatment, special stains like modified Ziehl–Neelsen stain and Gram stain can be employed to differentiate the morphology of Nocardia from tuberculosis. Fine‐needle cytology from these cutaneous lesions helps in yielding adequate material for rapid and accurate diagnosis of immediate specific antibiotic treatment. We report a rare case that presented with clinical diagnosis of tuberculosis but turned out to be nocardiosis on cytomorphology with simple and most feasible fine‐needle aspiration method of tissue diagnosis and scrape cytology.  相似文献   
6.
ObjectiveTo investigate whether a three-dimensional (3-D) camera (Microsoft Kinect) and a smartphone can be used to accurately quantify the joint angular velocity and range of motion (ROM) compared to a criterion-standard 3-D motion analysis system during a lower limb spasticity assessment.DesignObservational, criterion-standard comparison study.SettingLarge rehabilitation center.ParticipantsA convenience sample of 35 controls, 35 patients with a neurologic condition, and 34 rehabilitation professionals (physiotherapists and rehabilitation doctors) participated (N=104).InterventionsNot applicable.Main Outcome MeasuresThe Modified Tardieu Scale was used to assess spasticity of the quadriceps, hamstrings, soleus, and gastrocnemius. Data for each trial were collected concurrently using the criterion-standard Optitrack 3-D motion analysis (3DMA) system, Microsoft Kinect, and a smartphone. Each healthy control participant was assessed by 1 health professional and each patient with a neurological condition was assessed by 3 health professionals. Spearman correlation coefficient and intraclass correlation coefficient with 95% confidence intervals were used to report the strength of the relationships investigated.ResultsThe smartphone and Microsoft Kinect demonstrated excellent concurrent validity with the 3DMA system. Overall, 74.8% of the relationships investigated demonstrated a very strong (≥0.80) correlation across all of the testing parameters. The Microsoft Kinect was superior to the smartphone for measuring joint start and end angle, the smartphone was superior for measuring joint angular velocity, and the 2 systems were comparable for measuring total joint ROM.ConclusionsThese findings provide preliminary evidence that user-friendly, low-cost technologies can be used to facilitate accurate measurements of joint angular velocity and angles during a lower limb spasticity assessment in a clinical setting.  相似文献   
7.
Morphometric analysis of anatomical landmarks allows researchers to identify specific morphological differences between natural populations or experimental groups, but manually identifying landmarks is time‐consuming. We compare manually and automatically generated adult mouse skull landmarks and subsequent morphometric analyses to elucidate how switching from manual to automated landmarking will impact morphometric analysis results for large mouse (Mus musculus) samples (n = 1205) that represent a wide range of ‘normal’ phenotypic variation (62 genotypes). Other studies have suggested that the use of automated landmarking methods is feasible, but this study is the first to compare the utility of current automated approaches to manual landmarking for a large dataset that allows the quantification of intra‐ and inter‐strain variation. With this unique sample, we investigated how switching to a non‐linear image registration‐based automated landmarking method impacts estimated differences in genotype mean shape and shape variance‐covariance structure. In addition, we tested whether an initial registration of specimen images to genotype‐specific averages improves automatic landmark identification accuracy. Our results indicated that automated landmark placement was significantly different than manual landmark placement but that estimated skull shape covariation was correlated across methods. The addition of a preliminary genotype‐specific registration step as part of a two‐level procedure did not substantially improve on the accuracy of one‐level automatic landmark placement. The landmarks with the lowest automatic landmark accuracy are found in locations with poor image registration alignment. The most serious outliers within morphometric analysis of automated landmarks displayed instances of stochastic image registration error that are likely representative of errors common when applying image registration methods to micro‐computed tomography datasets that were initially collected with manual landmarking in mind. Additional efforts during specimen preparation and image acquisition can help reduce the number of registration errors and improve registration results. A reduction in skull shape variance estimates were noted for automated landmarking methods compared with manual landmarking. This partially reflects an underestimation of more extreme genotype shapes and loss of biological signal, but largely represents the fact that automated methods do not suffer from intra‐observer landmarking error. For appropriate samples and research questions, our image registration‐based automated landmarking method can eliminate the time required for manual landmarking and have a similar power to identify shape differences between inbred mouse genotypes.  相似文献   
8.
目的:探讨中西医结合精准护理在日间腹腔镜胆囊切除术(laparoscopic cholecystectomy,LC)中的应用价值。方法:对2018年5月—2018年11月115例行日间LC术患者实施精准护理(观察组),并与同期住院行常规LC术患者92例(对照组)进行对比,观察组在常规护理的基础上,实施耳穴压豆联合穴位贴敷及精准护理方法,分析对比两组患者住院时间、护理满意度评分、术后疼痛评分、术后不良反应发生率等。结果:观察组住院时间、术后疼痛评分及术后不良反应发生率均明显低于对照组(P0.05),护理满意度评分明显高于对照组(P0.05)。结论:中西医结合精准护理可明显提高行日间LC术患者的护理质量,促进患者快速康复。  相似文献   
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Psychostimulant use disorders remain an unabated public health concern worldwide, but no FDA approved medications are currently available for treatment. Modafinil (MOD), like cocaine, is a dopamine reuptake inhibitor and one of the few drugs evaluated in clinical trials that has shown promise for the treatment of cocaine or methamphetamine use disorders in some patient subpopulations. Recent structure–activity relationship and preclinical studies on a series of MOD analogs have provided insight into modifications of its chemical structure that may lead to advancements in clinical efficacy. Here, we have tested the effects of the clinically available (R)‐enantiomer of MOD on extracellular dopamine levels in the nucleus accumbens shell, a mesolimbic dopaminergic projection field that plays significant roles in various aspects of psychostimulant use disorders, measured in vivo by fast‐scan cyclic voltammetry and by microdialysis in Sprague‐Dawley rats. We have compared these results with those obtained under identical experimental conditions with two novel and enantiopure bis(F) analogs of MOD, JBG1‐048 and JBG1‐049. The results show that (R)‐modafinil (R‐MOD), JBG1‐048, and JBG1‐049, when administered intravenously with cumulative drug‐doses, will block the dopamine transporter and reduce the clearance rate of dopamine, increasing its extracellular levels. Differences among the compounds in their maximum stimulation of dopamine levels, and in their time course of effects were also observed. These data highlight the mechanistic underpinnings of R‐MOD and its bis(F) analogs as pharmacological tools to guide the discovery of novel medications to treat psychostimulant use disorders.  相似文献   
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