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101.
目的:了解血样制备前后放置时间对艾滋病患者外周血CD4^+、CD8^+、细胞计数的影响.方法:用艾滋病患者外周血分别在室温放置6、24、48及72 h后进行样品制备,流式细胞仪检测CD4^+、CD8^+细胞绝对计数;以及样品制备后分别在2、24、48、72及168 h上机检测;结果用SPSS软件进行统计学分析.结果:血液在室温放置72 h之内制备,CD4^+细胞计数变化差异无统计学意义(P>0.05),CD8^+细胞计数72 h与6 h比较差异有统计学意义(P<0.05);血样制备后室温放置1周内CD4^+、CD8^+细胞计数差异无统计学意义(P>0.05).结论:血液制备前在室温放置72 h后CD8^+细胞计数有明显变化;血样立即制备后室温放置1周CD4^+、CD8^+细胞计数是相对稳定的.  相似文献   
102.
The aim of the present study was to evaluate motor area mapping using functional magnetic resonance imaging (fMRI) compared with electrical cortical stimulation (ECS). Motor mapping with fMRI and ECS were retrospectively compared in seven patients with refractory epilepsy in which the primary motor (M1) areas were identified by fMRI and ECS mapping between 2012 and 2019. A right finger tapping task was used for fMRI motor mapping. Blood oxygen level-dependent activation was detected in the left precentral gyrus (PreCG)/postcentral gyrus (PostCG) along the “hand knob” of the central sulcus in all seven patients. Bilateral supplementary motor areas (SMAs) were also activated (n = 6), and the cerebellar hemisphere showed activation on the right side (n = 3) and bilateral side (n = 4). Furthermore, the premotor area (PM) and posterior parietal cortex (PPC) were also activated on the left side (n = 1) and bilateral sides (n = 2). The M1 and sensory area (S1) detected by ECS included fMRI-activated PreCG/PostCG areas with broader extent. This study showed that fMRI motor mapping was locationally well correlated to the activation of M1/S1 by ECS, but the spatial extent was not concordant. In addition, the involvement of SMA, PM/PPC, and the cerebellum in simple voluntary movement was also suggested. Combination analysis of fMRI and ECS motor mapping contributes to precise localization of M1/S1.  相似文献   
103.
104.
以梯度折射率透镜(自聚焦透镜)为摄像镜头,通过光电转换,结合数字信号处理和数据库技术.设计并实现了数字化口腔内窥镜。临床应用表明,所研制的自聚焦口腔内窥镜不仅操作简单、成像清晰且便于对患者的各种信息进行管理、查询,有望成为牙科医生必备的一种新诊疗设备。  相似文献   
105.
萸黄连为“相反为制”改变饮片药性的代表性炮制品之一,首载于《韩氏医通》,炮制方法为吴茱萸汁与净黄连拌匀闷润后炒干即得,即通过吴茱萸制黄连在保留黄连泻火解毒功效的基础上降低了黄连的苦寒之性,使黄连寒而不滞,可清气分湿热,对肝气犯胃、呕吐吞酸等病症有良好疗效。作为相反为制、药汁制的代表品种,萸黄连饮片收录于2020年版《中华人民共和国药典》和多个地方炮制规范中,其炮制工艺研究及优选一直备受关注。现代研究表明,萸黄连除含有小檗碱、药根碱、巴马汀等黄连中的成分外,还含有吴茱萸碱、吴茱萸次碱、柠檬苦素等吴茱萸中的成分,具有抗炎、抗菌、抗肿瘤等药理活性。该文对近20年萸黄连相关的研究报道进行整理归纳,从萸黄连的炮制历史及工艺、药效药性、质量评价和临床应用等方面进行综述,发现萸黄连在各省市炮制规范收载的炮制方法及标准差异较大,主要涉及吴茱萸汁的制备方法、吴茱萸汁的用量和炮制终点的判断标准等方面;此外,不同研究期间萸黄连炮制前后主要成分的变化情况差异较大,推测与萸黄连的炮制工艺和质量标准不同有关。该综述可为完善萸黄连的质量评价体系提供参考。  相似文献   
106.
In this article, we present the concept of reading time regularity (RTR) as a measure to capture reading process dynamics. The first study is concerned with examining one of the assumptions of RTR, namely, that process measures of reading, such as eye movement fluctuations and fixation durations, exhibit higher regularity when contingent on sequentially structured information, such as texts. To test this, eye movements of 26 German native speakers were recorded during reading-unrelated and reading-related tasks. To analyze the data, we used recurrence quantification analysis and sample entropy analysis to quantify the degree of temporal structure in time series of gaze steps and fixation durations. The results showed that eye movements become more regular in reading compared to nonreading conditions. These effects were most prominent when calculated on the basis of gaze step data. In a second study, eye movements of 27 native speakers of German were recorded for five conditions with increasing linguistic information. The results replicate the findings of the first study, verifying that these effects are not due to mere differences in task instructions between conditions. Implications for the concept of RTR and for future studies using these metrics in reading research are discussed.  相似文献   
107.
Lead-free piezoelectric powders (K0.44Na0.52Li0.04)(Nb0.82Ta0.10Sb0.04)O3 were obtained by conventional and microwave-assisted reactive heating. Firstly, the synthesis of the material was carried out following the mixed oxide route and employing both traditional methods and microwave technology. Thermogravimetry, X-ray diffraction, field emission scanning electron microscopy and electrical properties analyses were evaluated. X-ray diffraction of the powders calcined by the microwave process shows the formation of perovskite structure with orthorhombic geometry, but it is possible to observe the presence of other phases. The presence of the secondary phases found can have a great influence on the heating rate during the synthesis on which the kinetics of the reaction of formation of the piezoelectric compound depend. The calcined powder was sintered at different temperatures by conventional and non-conventional processes. The microstructure of the ceramics sintered by microwave at 1050 °C for 10 min shows perovskite cubes with regular geometry, of size close to 2–5 µm. However, the observed porosity (~8%), the presence of liquid phase and secondary phases in the microstructure of the microwave sintered materials lead to a decrease of the piezoelectric constant. The highest d33 value of 146 pC/N was obtained for samples obtained by conventional at 1100 °C 2 h compared to samples sintered by microwave at 1050 °C 10 min (~15 pC/N).  相似文献   
108.
Recent research revealed a surprisingly large range of cognitive operations to be preserved during sleep in humans. The new challenge is therefore to understand functions and mechanisms of processes, which so far have been mainly investigated in awake subjects. The current study focuses on dynamic changes of brain oscillations and connectivity patterns in response to environmental stimulation during non-REM sleep. Our results indicate that aurally presented names were processed and neuronally differentiated across the wake-sleep spectrum. Simultaneously recorded EEG and MEG signals revealed two distinct clusters of oscillatory power increase in response to the stimuli: (1) vigilance state-independent θ synchronization occurring immediately after stimulus onset, followed by (2) sleep-specific α/σ synchronization peaking after stimulus offset. We discuss the possible role of θ, α, and σ oscillations during non-REM sleep, and work toward a unified theory of brain rhythms and their functions during sleep.SIGNIFICANCE STATEMENT Previous research has revealed (residual) capacity of the sleeping human brain to interact with the environment. How sensory processing is realized by the neural assemblies in different stages of sleep is however unclear. To tackle this question, we examined simultaneously recorded MEG and EEG data. We discuss the possible role of θ, α, and σ oscillations during non-REM sleep. In contrast to versatile θ band response that reflected early stimulus processing step, succeeding α and σ band activity was sensitive to the saliency of the incoming information, and contingent on the sleep stage. Our findings suggest that the specific reorganization of mechanisms involved in later stages of sensory processing takes place upon falling asleep.  相似文献   
109.
Bovine respiratory disease complex (BRDC) is a comprehensive disease in cattle caused by various viral and bacterial infections. Among them, bovine herpesvirus type I (BoHV−1) and bovine viral diarrhea virus (BVDV) play important roles and have caused huge financial losses for the cattle industry worldwide. At present, vaccines against BRDC include trivalent attenuated BoHV−1, BVDV−1, and BVDV−2 live vaccines, BoHV−1 live attenuated vaccines, and BoHV−1/BVDV bivalent live attenuated vaccines, which have limitations in terms of their safety and efficacy. To solve these problems, we optimized the codon of the BVDV−1 E2 gene, added the signal peptide sequence of the BoHV−1 gD gene, expressed double BVDV−1 E2 glycoproteins in tandem at the BoHV−1 gE gene site, and constructed a BoHV−1 genetics-engineered vectored vaccine with gE gene deletion, named BoHV−1 gE/E2−Linker−E2+ and BoHV−1 ΔgE. This study compared the protective effects in BoHV−1, BoHV−1 ΔgE, BoHV−1 gE/E2−Linker−E2+, and BVDV−1 inactivated antigen immunized guinea pigs and calves. The results showed that BoHV−1 gE/E2−Linker−E2+ could successfully induce guinea pigs and calves to produce specific neutralizing antibodies against BVDV−1. In addition, after BoHV−1 and BVDV−1 challenges, BoHV−1 gE/E2−Linker−E2+ can produce a specific neutralizing antibody response against BoHV−1 and BVDV−1 infections. Calves immunized with this type of virus can be distinguished as either vaccinated animals (gE-) or naturally infected animals (gE+). In summary, our data suggest that BoHV−1 gE/E2−Linker−E2+ and BoHV−1 ΔgE have great potential to prevent BVDV−1 or BoHV−1 infection.  相似文献   
110.
There are many factors influencing the accuracy of surface topography measurement results: one of them is the vibrations caused by the high-frequency noise occurrence. It is extremely difficult to extract results defined as noise from the real measured data, especially the application of various methods requiring skilled users and, additionally, the improper use of software may cause errors in the data processing. Accordingly, various thresholding methods for the minimization of errors in the raw surface topography data processing were proposed and compared with commonly used (available in the commercial software) techniques. Applied procedures were used for the minimization of errors in the surface topography parameters (from ISO 25178 standard) calculation after the removal and reduction, respectively, of the high-frequency noise (S-filter). Methods were applied for analysis of the laser-textured surfaces with a comparison of many regular methods, proposed previously in the commercial measuring equipment. It was found that the application of commonly used algorithms can be suitable for the processing of the measured data when selected procedures are provided. Moreover, errors in both the measurement process and the data processing can be reduced when thresholding methods support regular algorithms and procedures. From applied, commonly used methods (regular Gaussian regression filter, robust Gaussian regression filter, spline filter and fast Fourier transform filter), the most encouraging results were obtained for high-frequency noise reduction in laser-textured details when the fast Fourier transform filter was supported by a thresholding approach.  相似文献   
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