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In vivo label-free measurement of blood flow velocity symmetry based on dual line scanning third-harmonic generation microscopy excited at the 1700 nm window 被引量:1
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作者 Hui Cheng Jincheng Zhong +1 位作者 Ping Qiu Ke Wang 《Journal of Innovative Optical Health Sciences》 SCIE EI CSCD 2024年第1期61-68,共8页
Measurement of bloodflow velocity is key to understanding physiology and pathology in vivo.While most measurements are performed at the middle of the blood vessel,little research has been done on characterizing the in... Measurement of bloodflow velocity is key to understanding physiology and pathology in vivo.While most measurements are performed at the middle of the blood vessel,little research has been done on characterizing the instantaneous bloodflow velocity distribution.This is mainly due to the lack of measurement technology with high spatial and temporal resolution.Here,we tackle this problem with our recently developed dual-wavelength line-scan third-harmonic generation(THG)imaging technology.Simultaneous acquisition of dual-wavelength THG line-scanning signals enables measurement of bloodflow velocities at two radially symmetric positions in both venules and arterioles in mouse brain in vivo.Our results clearly show that the instantaneous bloodflow velocity is not symmetric under general conditions. 展开更多
关键词 1700 nm-Window third-harmonic generation imaging blood flow velocity
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Changes in mean cerebral blood flow velocity during cognitive task-induced cerebral fatigue in high performance fighter pilots 被引量:3
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作者 Yongsheng Chen 《Neural Regeneration Research》 SCIE CAS CSCD 2008年第11期1261-1264,共4页
BACKGROUND: Several studies have demonstrated that sustained cognitive tasks can induce cognitive fatigue and that the mean cerebral blood flow velocity changes in some cerebral regions during cerebral fatigue. OBJEC... BACKGROUND: Several studies have demonstrated that sustained cognitive tasks can induce cognitive fatigue and that the mean cerebral blood flow velocity changes in some cerebral regions during cerebral fatigue. OBJECTIVE: To dynamically monitor the changes in mean cerebral blood flow velocity in different brain regions of high performance fighter pilots during mental arithmetic tasks and consecutive performance tasks. DESIGN, TIME AND SETTING: The present neurophysiological trial, based on controlled observation, was performed at the Laboratory of Neurophysiology, Institute of Aviation Medicine, Air Force of China between January 2003 and December 2005. PARTICIPANTS: Forty-five males, high performance fighter pilots, averaging (27.6±2.5) years, were recruited for this study. METHODS: The mean cerebral blood flow velocity in the anterior cerebral artery, middle cerebral artery, and posterior cerebral artery of subjects was dynamically tested using transcranial Doppler during 5- hour mental arithmetic tasks and during 5- hour consecutive performance tasks. The neurobehavioral ability index was analyzed throughout each trial according to the number of correct responses, false responses, and lost responses. Simultaneously, cerebral cognitive fatigue-induced lethargy was assessed by the Stanford Sleepiness Scale. MAIN OUTCOME MEASURES: Changes in mean cerebral blood flow velocity in the anterior cerebral artery, middle cerebral artery, and posterior cerebral artery; neurobehavioral ability index of mental arithmetic and consecutive performance tasks; Stanford Sleepiness Scale scores. RESULTS: During mental arithmetic tasks, the mean cerebral blood flow velocity in the anterior cerebral artery increased during hour 2 and decreased after hour 4. There was no significant change in mean cerebral blood flow velocity in the middle cerebral artery and posterior cerebral artery. During hour 4, cerebral cognitive fatigue was observed and, simultaneously, Stanford Sleepiness Scale scores demonstrated the presence of fatigue. During such a stage, the neurobehavioral ability index decreased, indicating a decline in performance ability. During consecutive performance tasks, the mean cerebral blood flow velocity declined earlier in the posterior cerebral artery compared to the middle cerebral artery. CONCLUSION: Five- hour mental arithmetic tasks have few effects on cerebral functions and do not lead to a significant change in mean cerebral blood flow velocity. Five-hour consecutive performance tasks can induce cerebral cognitive fatigue, and a marked decline in mean cerebral blood flow velocity. 展开更多
关键词 cerebral cognitive fatigue cerebral artery blood velocity neurobehavioral ability index Stanford Sleepiness Scale
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Trans-Thoracic Echocardiographic Aortic Blood Flow Peak Velocity Variation, Distance Minute, Aortic Velocity Time Integral and Postoperative Outcome in Pediatric Surgical Patients—An Observational Pilot Study Protocol 被引量:1
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作者 Claudine Kumba 《Open Journal of Internal Medicine》 2020年第1期90-95,共6页
Background: A Randomized Controlled Trial (RCT) has been elaborated where goal directed fluid and hemodynamic therapy (GDFHT) will be realized with trans-thoracic echocardiographic aortic blood flow peak velocity vari... Background: A Randomized Controlled Trial (RCT) has been elaborated where goal directed fluid and hemodynamic therapy (GDFHT) will be realized with trans-thoracic echocardiographic aortic blood flow peak velocity variation (ΔVpeak) and distance minute (DM) to guide fluid therapy and hemodynamics in high risk pediatric surgical patients. This RCT will clarify the impact of GDFHT with ΔVpeak and DM on postoperative outcome in terms of morbidity, length of stay in the intensive care unit (LOSICU), length of mechanical ventilation (LMV) and length of hospital stay (LOS) in children. To determine values of ΔVpeak, DM and VTI predictive of these postoperative outcomes, an observational pilot study will be realized. This pilot study is described here. The primary objective of this study is to determine values of ΔVpeak, DM and ITV predictive of postoperative outcome in children in terms of morbidity. The secondary objectives are to determine values of ΔVpeak, DM and ITV predictive of LOSICU, LMV, LOS, intraoperative, postoperative fluid administration and vasoactive-inotropic therapy. Methods: 500 - 1000 children aged less than 18 years will be included prospectively. Statistic analysis will be realized with XLSTAT 2019.4.2 software or plus. Results and Conclusions: This trial protocol will determine values of ΔVpeak, DM and ITV with echocardiography predictive of postoperative outcome in children. 展开更多
关键词 Children AORTIC blood Flow Peak velocity Variation AORTIC velocity Time INTEGRAL Distance MINUTE Postoperative Outcome Pilot Study Protocol Trans-Thoracic Echocardiography
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Optimal velocity encoding during measurement of cerebral blood flow volume using phase-contrast magnetic resonance angiography
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作者 Gang Guo Yonggui Yang Weiqun Yang 《Neural Regeneration Research》 SCIE CAS CSCD 2011年第23期1796-1800,共5页
This study investigated the effect of velocity encoding on measurement of brain blood flow and blood volume of inflow and outflow using phase-contrast magnetic resonance angiography. A single two-dimensional phase-con... This study investigated the effect of velocity encoding on measurement of brain blood flow and blood volume of inflow and outflow using phase-contrast magnetic resonance angiography. A single two-dimensional phase-contrast magnetic resonance angiography slice was applied perpendicular to the internal carotid artery and the vertebral artery at C2 level. For each subject, the velocity encoding was set from 30 to 90 cm/s with an interval of 10 cm/s for a total of seven settings. Various velocity encodings greatly affected blood flow volume, maximal blood flow velocity and mean blood flow velocity in the internal carotid artery, but did not significantly affect vertebral arteries and jugular veins. When velocity encoding was 60-80 cm/s, the inflow blood volume was 655 _+ 118 mL/min, and the outflow volume was 506 _+ 186 mL/min. The ratio of outflow/inflow was steady at 0.78-0.83, and there was no aliasing in any of the images. These findings suggest that velocity encodings of 60 80 cm/s should be selected during measurement of cerebral blood flow volume using phase-contrast magnetic resonance angiography. 展开更多
关键词 cerebral blood flow velocity encoding PHASE-CONTRAST magnetic resonance imaging
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Influence of High-Velocity Blood Flow on Right-to-Left Shunt in Patients with Patent Foramen Ovale during the Valsalva Maneuver 被引量:2
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作者 Xiaohui Zhang Baomin Liu 《Journal of Biosciences and Medicines》 2019年第1期13-22,共10页
In this study, we investigated the changes in the right-to-left shunt (RLS) of the patent foramen ovale (PFO) at different phases of the Valsalva maneuver and analyzed the possible mechanisms. The study population con... In this study, we investigated the changes in the right-to-left shunt (RLS) of the patent foramen ovale (PFO) at different phases of the Valsalva maneuver and analyzed the possible mechanisms. The study population consisted of 57 patients with symptoms highly suggestive of a PFO. These patients had been diagnosed with apsychia, migraine with aura, cerebral infarction, transient ischemic attack (TIA), and cerebral ischemia with unknown cause. Routine echocardiography was performed in all patients to rule out a cardiac malformation. Contrast-transcranial Doppler (c-TCD) and contrast-enhanced transthoracic echocardiography (c-TTE) were used to visualize and quantify the RLS. The standard apical four chamber view was used to observe the changes of E peak, A peak, and velocity-time integral (VTI) ratio of tricuspid blood flow during the strain phase and release phase of the Valsalva maneuver. Paired t-test was used to compare E peak, A peak, and VTI ratio of tricuspid blood flow during the different phases. The right-to-left shunt across the PFO (PFO-RLS) was graded in the two phases and compared by Kruskal-Wallis test. Compared with the strain phase of the Valsalva maneuver, the parameters of E, A, and VTI in diastolic period in patients with PFO-RLS at the release phase were significantly increased [54.30 ± 13.65 cm/s vs 100.35 ± 21.11 cm/s, 42.21 ± 12.32 cm/s vs 57.30 ± 18.88 cm/s, 10.34 ± 3.27 cm/s vs 19.58 ± 4.56 cm/s, respectively], and the difference was statistically significant. The positive consequence of PFO-RLS, as diagnosed by c-TTE with the Valsalva maneuver at the release phase of the Valsalva maneuver, was significantly higher than that at the strain phase of the Valsalva maneuver. At the beginning of release phase of the Valsalva maneuver, decreased intrathoracic pressure led to increased venous backflow into the right atrium. Thus, high-velocity blood flow rapidly pushed the PFO open, which resulted in a significant increase in the PFO-RLS. Therefore, the increase of the PFO-RLS during the Valsalva maneuver is caused by the impact of high-velocity blood flow the PFO. 展开更多
关键词 PATENT Foramen Ovale Right to Left SHUNT VALSALVA MANEUVER HIGH-velocity blood Flow
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The Effects of Chinese Medicines on Micro-circulation of Nail Folds and Blood Flow Velocity of Limbs in the Patients with Arteriosclerotic Obliteration
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作者 葛辛 葛芃 +2 位作者 彭玉清 陈云翔 段树民 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2003年第2期87-89,共3页
The effects of Chinese medicines on micro-circulation and blood flow velocity in arteries of the lower limbs were observed in 33 patients with arteriosclerotic obliteration(ASO).The results showed that the integral va... The effects of Chinese medicines on micro-circulation and blood flow velocity in arteries of the lower limbs were observed in 33 patients with arteriosclerotic obliteration(ASO).The results showed that the integral values of micro-circulation after treatment were obviously higher than those before treatment (P<0.05 or P<0.01).Blood flow velocity in arteries of the lower limbs determined with the color Doppler ultrasound detecting method after treatment were also obviously higher than those before treatment (P<0.05 or P<0.01).In tbis series of 33 ASO patients,the markedly effective rate was 36.36%,and the total effective rate was 63.64%.The observation indicates that the recipe prescribed according to the principle of supplementing qi and activating blood circulation can effectively improve micro-circulation in ASO patients,and accelerate blood flow in arteries of the lower limbs. 展开更多
关键词 PHYTOTHERAPY Aged Arteriosclerosis Obliterans blood Flow velocity Drugs Chinese Herbal EXTREMITIES Female Humans Male Microcirculation Middle Aged NAILS
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A FREQUENCY DOMAIN QUANTITATIVE MEASUREMENT METHOD FOR BLOOD FLOW VELOCITY WITH BIDIRECTIONAL DOPPLERULTRASOUND AVOIDING DOWN-BAND CHANNEL
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作者 Wang Weiqi,Shao Qianming,Yu Jianguo(Department of Electronic Engineering,Fudan University, Shanghai, 200433, China) 《Chinese Journal of Biomedical Engineering(English Edition)》 1996年第4期147-154,共8页
The up-band signal of the second ultrasonic beam contained reversecomPOnent or blooll now. Using double ultrasonic beam,bidirectional Doppler ultrasound can avoid the use or two kinds or band filters and be simplified... The up-band signal of the second ultrasonic beam contained reversecomPOnent or blooll now. Using double ultrasonic beam,bidirectional Doppler ultrasound can avoid the use or two kinds or band filters and be simplified into a singlekind or band filter. In order to make the output more accurate,the inrluence of angle effect can be overcome by the table-out method and another special methodcalled cose recorrection.The experiment result is that when the deviation angle varies from-- 18' to +20' the relative error or output is less than 5%. 展开更多
关键词 Ultrasound blood FLow velocity FREQUENCY separation Down-bandchannel
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Abnormality of peripheral nerve conduction velocity associated with illness course, symptoms and fasting blood glucose in patients with type 2 diabetes mellitus
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作者 Suijing Cui Jinhua Qiu Weiliang Luo 《Neural Regeneration Research》 SCIE CAS CSCD 2006年第9期862-864,共3页
BACKGROUND: It has shown that abnormality of peripheral nerve conduction velocity during onset of diabetes mellitus is not related to age and sex, but to symptoms, illness course and level of fasting blood glucose. OB... BACKGROUND: It has shown that abnormality of peripheral nerve conduction velocity during onset of diabetes mellitus is not related to age and sex, but to symptoms, illness course and level of fasting blood glucose. OBJECTIVE: To measure correlation of abnormality of peripheral nerve conduction velocity with various illness courses, symptoms and levels of fasting blood glucose of patients with type 2 diabetes mellitus. DESIGN: Case analysis. SETTING: Department of Neurology, Central People's Hospital of Huizhou. PARTICIPANTS: A total of 128 patients who were diagnosed as type 2 diabetes mellitus were selected from Central People's Hospital of Huizhou from September 2001 to October 2005. There were 75 males and 53 females aged 32-83 years and the illness course ranged from 1 month to 20 years. METHODS: All 128 patients with type 2 diabetes mellitus received neuro-electrophysiological study and their clinical data were retrospectively analyzed to measure peripheral nerve conduction velocity and fasting blood glucose so as to investigate the correlation of peripheral nerve conduction velocity with clinical symptoms, illness course and levels of fasting blood glucose. MAIN OUTCOME MEASURES: Correlation of peripheral nerve conduction velocity with clinical symptoms, illness course and levels of fasting blood glucose. RESULTS: All 128 patients with type 2 diabetes mellitus were involved in the final analysis. ① Among 128 patients, 114 patients had abnormality of peripheral nerve conduction velocity; 110 patients had clinical symptoms, including 102 patients having abnormality of peripheral nerve conduction velocity; 18 patients did not have clinical symptoms, including 12 patients having abnormality of peripheral nerve conduction velocity. There were significant differences between them (χ 2=8.275, P =0.04). ② Among 128 patients, illness course of 75 patients was equal to or less than 5 years, including 27 patients having abnormality of peripheral nerve conduction velocity; illness course of 53 patients was more than 5 years, including 35 patients having abnormality of peripheral nerve conduction velocity. There were significant differences between them (χ 2=11.469, P =0.003). ③ Among 128 patients, levels of fasting blood glucose of 75 patients was equal to or lower than 11 mmol/L, including 41 patients having abnormality of peripheral nerve conduction velocity; levels of fasting blood glucose of 53 patients was higher than 11 mmol/L, including 38 patients having abnormality of peripheral nerve conduction velocity. There were significant differences between them (χ 2=4.023, P =0.134). CONCLUSION: ① Abnormality of peripheral nerve conduction velocity of patients with type 2 diabetes mellitus is related to illness courses and clinical symptoms. The longer the illness course is, the severer the abnormality of peripheral nerve conduction velocity is. Abnormality of peripheral nerve conduction velocity always occurs on patients who have clinical symptoms. ② Abnormality of peripheral nerve conduction velocity is not related to levels of fasting blood glucose. 展开更多
关键词 TYPE symptoms and fasting blood glucose in patients with type 2 diabetes mellitus Abnormality of peripheral nerve conduction velocity associated with illness course
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子宫动脉血流频谱联合e-Flow胎盘血流在妊娠期高血压103例中的应用价值
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作者 赵媛媛 王妙英 +5 位作者 王婷婷 董有伟 石丽洁 赵鹏 王海波 焦鹏增 《安徽医药》 CAS 2024年第12期2479-2482,共4页
目的研究e-Flow胎盘血流结合子宫动脉血流频谱在妊娠期高血压疾病中的应用价值。方法回顾性分析2021年5月至2023年2月邯郸市中心医院103例纳入时无高血压,后随访出现妊娠期高血压孕妇作为妊娠期高血压组,选择产检正常且无高血压的110例... 目的研究e-Flow胎盘血流结合子宫动脉血流频谱在妊娠期高血压疾病中的应用价值。方法回顾性分析2021年5月至2023年2月邯郸市中心医院103例纳入时无高血压,后随访出现妊娠期高血压孕妇作为妊娠期高血压组,选择产检正常且无高血压的110例正常孕妇作为健康组。收集妊娠期高血压组未出现高血压时以及健康组的子宫动脉血流频谱和e-Flow胎盘血流数据,获得子宫动脉阻力指数、搏动指数、收缩期峰值与舒张末期流速比值(S/D),舒张早期切迹与胎盘血管图像;采用受试者操作特征曲线(ROC曲线)分析各指标单独以及联合预测妊娠期高血压的价值。结果妊娠期高血压组搏动指数、阻力指数及S/D值高于健康组(P<0.05)。子宫动脉舒张早期切迹存在率方面,妊娠期高血压组相较于健康组更高(P<0.05)。妊娠期高血压组三级绒毛动脉计数少于健康组[(2.34±0.48)个比(4.36±0.53)个,P<0.05]。ROC曲线显示,搏动指数、阻力指数、S/D、三级绒毛动脉计数联合检查对妊娠期高血压的灵敏度、特异度为74.80%、93.30%,预测价值高于单独检查。结论子宫动脉血流频谱联合e-Flow胎盘血流能有效预测妊娠期高血压发生,可作为临床早期疾病评估的有效检查方式。 展开更多
关键词 高血压 妊娠性 脉冲波多普勒超声成像 子宫动脉 血流频谱 胎盘血流 子宫动脉搏动指数 阻力指数
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Wrist blood flow signal-based computerized pulse diagnosis using spatial and spectrum features 被引量:7
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作者 Dong-Yu Zhang Wang-Meng Zuo +2 位作者 David Zhang Hong-Zhi Zhang Nai-Min Li 《Journal of Biomedical Science and Engineering》 2010年第4期361-366,共6页
ABSTRACT Current computerized pulse diagnosis is mainly based on pressure and photoelectric signal. Considering the richness and complication of pulse diagnosis information, it is valuable to explore the feasibility o... ABSTRACT Current computerized pulse diagnosis is mainly based on pressure and photoelectric signal. Considering the richness and complication of pulse diagnosis information, it is valuable to explore the feasibility of novel types of signal and to develop appropriate feature representation for diagnosis. In this paper, we present a study on computerized pulse diagnosis based on blood flow velocity signal. First, the blood flow velocity signal is collected using Doppler ultrasound device and preprocessed. Then, by locating the fiducial points, we extract the spatial features of blood flow velocity signal, and further present a Hilbert-Huang transform-based method for spectrum feature extraction. Finally, support vector machine is applied for computerized pulse diagnosis. Experiment results show that the proposed method is effective and promising in distinguishing healthy people from patients with cho- lecystitis or nephritis. 展开更多
关键词 Pulse Diagnosis blood Flow velocity Hilbert-Huang TRANSFORM Support Vector Machine
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Possible key residues that determine left gastric artery blood flow response to PACAP in dogs 被引量:2
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作者 Mu-Xin Wei Ping Hu +4 位作者 Ping Wang Satoru Naruse Kiyoshi Nokihara Victor Wray Tsuyoshi Ozaki 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第38期4865-4870,共6页
AIM:To determine the effect of pituitary adenylate cy-clase-activating polypeptide (PACAP) on left gastric artery (LGA) flow and to unveil the structural or functional important sites that may be critical for discrimi... AIM:To determine the effect of pituitary adenylate cy-clase-activating polypeptide (PACAP) on left gastric artery (LGA) flow and to unveil the structural or functional important sites that may be critical for discrimination of different receptor subtypes. METHODS: Peptides, including PACAP-27, PACAP-38, amino acid substituted PACAP-27 and C-terminus truncated analogues PACAP (27-38), were synthesized by a simultaneous multiple solid-phase peptide synthesizer. Flow probes of an ultrasound transit-time blood flowmeter were placed around the LGA of beagle dogs. Whenpeptides were infused intravenously, the blood flow was measured.RESULTS: [Ala4, Val5]-PACAP-27 caused a concentration-dependent vasodepressor action which was similar to that caused by PACAP-27. The LGA blood flow response to [Ala4, Val5]-PACAP-27 was significantly higher than that to PACAP-27, which was similar to that to vasoactive intestinal polypeptide (VIP) at the same dose. [Ala6]-PACAP-27 did not increase the peak LGA ? ow. [Gly8]-PACAP-27 showed a similar activity to VIP. [Asn24, Ser25, Ile26]-PACAP-27 did not change the activity of peptides at all doses. CONCLUSION: NH2 terminus is more important to biological activity of peptides and specifi c receptor recognition than COOH-terminus. 展开更多
关键词 Pituitary adenylate cyclase-activating poly-peptide Pituitary adenylate cyclase-activating polypeptide 27 Pituitary adenylate cyclase-activating polypeptide P38 Left gastric artery blood fl ow
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The Flow Behavior of Red Blood Cell Reduced Deformability in Microchannel
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作者 Fen Li Rui Duan Hui Li 《医用生物力学》 EI CAS CSCD 北大核心 2019年第A01期116-117,共2页
Blood cells are mainly(~99%)comprised of red blood cells.The most remarkable properties of are their high deformability,which allow they flow through microcapillaries of diameter even smaller than their size.The RBC’... Blood cells are mainly(~99%)comprised of red blood cells.The most remarkable properties of are their high deformability,which allow they flow through microcapillaries of diameter even smaller than their size.The RBC’s remarkable mechanical properties originate from the unique architecture of its membrane.To study the mechanism of RBC’s deformability,a commonly adopted approach is to localize the cytoskeleton protein by immunofluorescence,followed by exploring the changes of cytoskeleton protein during cell deformation.During this process,the fixed treatment of RBC using GA and PFA is of great importance.However,RBC’s deformability is reduced by the fixation process and skeletal protein of membrane is changed accordingly.The flow behavior of red RBCs through the microchannel also changed.Given the difficulty of observing RBC flow in vivo,in vitro simulation by virtue of microfluidic devices provides a feasible alternative.An important physiological phenomenon of the blood flow is the formation of cell free layer(CFL),with RBCs show a tendency to concentrate towards the central axis of the pipeline and move faster than the plasma layer.However,this phenomena is weaken if the stiffness of the membrane increase,which occurs in some disease,such as hereditary spherocytosis and hereditary elliptocytosis.To study the effects of GA and PFA fix treatment on RBC deformability,a microfluidic platform is employed to measuring the CFL and flow velocity of blood flow in this work.The PDMS micro flow channel used is 100 micrometers in width and 50 micrometers in deep.The RBC suspension is fed into the flow channel by the injection pump(NE-1000.USA),and the experiments are observed and recorded by the inverted microscope(IX70,Olympus,Japan)and high-speed camera(Memrecam GX-1,NAC,Japan)system.Three GA concentrations,i.e.,0.000 5,0.000 75,and 0.001 wt.%were used.Meanwhile,the effect of PFA at a concentration of 2wt.%work with GA was also investigated.Images of the flowing RBCs are processed mainly based on Memrecam GXLink.The results show that,the diameter of the RBC be treated is bigger and the shape of the RBC is became more flat after treated.Some of RBCs lost their biconcave structure.When the RBC suspension with 5%Hct flow in the microchannel,the CFL thickness decrease after being treated.And with concentrations of GA increase,the CFL thickness become thinner.The CFL thickness decrease significantly when GA and 2 wt.%PFA work combined.The velocity of RBCs decreases after treated with the GA or/and 2wt.%PFA.GA is known to relieve the dissolution of red blood cells during fluorescence labeling.On the other hand,the crosslinking of the aldehyde group(-cho)of GA with the amino group(-nh2)of RBC membrane protein will change the conformation of the membrane protein and its visco-elastic properties in turn.Then,the transparent fluidity orrheology characteristics of RBC is altered.Since GA and PFA are commonly used to immobilize red blood cells and keep the fluorescence constant,and PFA works similarly as GA,as a result,the variation of membrane protein conformation is intensified,and the membrane becomes stiffer. 展开更多
关键词 RED blood CELL micro channel fixed treatment CELL free layer velocity distribution
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Blood Flow Simulation in the Femoral Artery
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作者 Camilo A.Naranjo Andrés F.Villa +3 位作者 Juan C.Vélez Ricardo A.Prato Alberto J.Cadena Juan P.Tello 《Journal of Electronic Science and Technology》 CAS CSCD 2018年第3期269-279,共11页
This paper presents the development of the blood flow simulation in two dimensions over the real geometry of the femoral artery. The Navier-Stokes equations are solved using the finite element method, to obtain the di... This paper presents the development of the blood flow simulation in two dimensions over the real geometry of the femoral artery. The Navier-Stokes equations are solved using the finite element method, to obtain the distributions of the blood pressure and flow velocity in multiple instants of time and different places of the femoral artery and thus determine the current condition of the blood vessels. The velocity field shows a laminar behavior,where, the velocity is higher in the center of the artery and decreases as the blood flow approaches artery walls. In spite of all artery and blood flow properties not being considered, the values of pressure and velocity obtained are within the normal ranges. Finally the model is used to verify if there exist irregularities in the blood flow in both healthy subjects and sick patients. 展开更多
关键词 blood flow femoral artery finite elements NAVIER-STOKES PRESSURE velocity
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Cerebral blood flow volume measurements of the carotid artery and ipsilateral branches using two-dimensional phase-contrast magnetic resonance angiography
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作者 Gang Guo Yonggui Yang Weiqun Yang 《Neural Regeneration Research》 SCIE CAS CSCD 2011年第30期2367-2371,共5页
The optimal velocity encoding of phase-contrast magnetic resonance angiography (PC MRA) in measuring cerebral blood flow volume (BFV) ranges from 60 to 80 cm/s. To verify the accuracy of two-dimensional (2D) PC ... The optimal velocity encoding of phase-contrast magnetic resonance angiography (PC MRA) in measuring cerebral blood flow volume (BFV) ranges from 60 to 80 cm/s. To verify the accuracy of two-dimensional (2D) PC MRA, the present study localized the region of interest at blood vessels of the neck using PC MRA based on three-dimensional time-of-flight sequences, and the velocity encoding was set to 80 cm/s. Results of the measurements showed that the error rate was 7.0±6.0% in the estimation of BFV in the internal carotid artery, the external carotid artery and the ipsilateral common carotid artery. There was no significant difference, and a significant correlation in BFV between internal carotid artery + external carotid artery and ipsilateral common carotid artery. In addition, the BFV of the common carotid artery was correlated with that of the ipsilateral internal carotid artery. The main error was attributed to the external carotid artery and its branches. Therefore, after selecting the appropriate scanning parameters and protocols, 2D PC MRA is more accurate in the determination of BFV in the carotid arteries. 展开更多
关键词 two-dimensional phase-contrast magnetic resonance angiography blood flow three-dimensional time-of-flight phase-contrast magnetic resonance angiography internal carotid artery common carotid artery external carotid artery velocity encoding
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RETINAL SPECTRAL IMAGING AND BLOOD FLOW MEASUREMENT
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作者 PAUL LEMAILLET DONALD D.DUNCAN +3 位作者 ART LOMPADO MOHAMED IBRAHIM QUAN DONG NGUYEN JESSICA C.RAMELLA-ROMAN 《Journal of Innovative Optical Health Sciences》 SCIE EI CAS 2010年第4期255-265,共11页
Measurement of both oxygen saturation and blood flow in the retinal vessels has proved to give important information about the eye health and the onset of eye pathologies such as diabetic retinopathy.In this study,we ... Measurement of both oxygen saturation and blood flow in the retinal vessels has proved to give important information about the eye health and the onset of eye pathologies such as diabetic retinopathy.In this study,we present the implementation,on a commercially available fundus camera,of a retinal imager and a retina blood flow velocimeter.The retinal imager uses division of aperture to acquire nine wavelength-dependent sub-images of the retina.Careful consideration is taken to improve image transfer by measuring the optical properties of the fundus camera and modeling the optical train in Zemax.This part of the setup is calibrated with optical phantoms of known optical properties that are also used to build a lookup table(LUT)linking phantom optical properties to measured reflectance.The retina blood flow velocimeter relies on tracking clusters of erythrocytes and uses a fast acquisition camera attached to a zoom lens,with a green illumination LED-engine.Calibration is provided using a calibrated quartz capillary tube and human blood at a known flow rate.Optical properties of liquid phantoms are retrieved from measured reflectance using the LUT,and blood flow measurements in the retina are presented. 展开更多
关键词 Retinal oximetry fundus ophthalmoscope multi-aperture camera blood flow velocity diabetic retinopathy
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A Mathematical Model for Pulsating Flow of Ionic Fluid under an Axial Electric Field: EMF Effect on Blood Flow
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作者 Mona A. EI-Naggar Medhat A. Messiery 《Journal of Physical Science and Application》 2012年第4期61-70,共10页
The present work introduces a mathematical model for ionic fluid that flows under the effect of both pulsating pressure and axial electromagnetic field. The fluid is treated as a Newtonian fluid applying Navier-Stokes... The present work introduces a mathematical model for ionic fluid that flows under the effect of both pulsating pressure and axial electromagnetic field. The fluid is treated as a Newtonian fluid applying Navier-Stokes equation. The fluid is considered as a neutral mixture of positive and negative ions. The effect of axial electric field is investigated to determine velocity profiles. Hydroelectric equation of the flow is deduced under dc and ac external electric field. Hence the effect of applied frequency (0-1 GHz) and amplitude (10-350 V/m) is illustrated. The ultimate goal is to approach the problem of EMF field interaction with blood flow. The applied pressure waveform is represented as such to simulate the systolic-diastolic behavior. Simulation was carried out using Maple software using blood plasma parameters; hence velocity profiles under various conditions are reported. 展开更多
关键词 Newtonian fluid navier-stokes ionic fluid blood flow electric field hydroelectric flow simulation velocity profiles EMF bioeffects.
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EFFECTS OF ACUPUNCTURE AT FENGCHI POINT (GB 20) ON CEREBRAL BLOOD FLOW 被引量:1
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作者 袁晓军 郝喜书 +2 位作者 赖仲平 赵晖 柳文仪 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 1998年第2期102-105,共4页
Blood velocity in the vertebral artery and the basilar artery was observed before and after acupuncture at Fengchi point (GB 20) in 97 patients by transcranial Doppler ultrasonic detecting. The results showed that the... Blood velocity in the vertebral artery and the basilar artery was observed before and after acupuncture at Fengchi point (GB 20) in 97 patients by transcranial Doppler ultrasonic detecting. The results showed that the blood velocity in patients with either high or low blood flow had significant changes after acupuncture (P 展开更多
关键词 Acupuncture Points Acupuncture Therapy Cerebrovascular Circulation ADULT Aged blood Flow velocity Cerebral Infarction Cervical Vertebrae FEMALE Humans HYPERTENSION Male Middle Aged Spinal Osteophytosis
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EFFECTS OF ELECTRO ACUPUNCTURE AND TWIRLING REINFORCING-REDUCING MANIPULATIONS ON VOLUME OF MICROCIRCULATORY BLOOD FLOW IN CEREBRAL PIA MATER
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作者 史仁华 姬广臣 +2 位作者 赵鲁鸣 王世军 董军 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 1998年第3期220-224,共5页
Effects of electroacupuncture (EA) and routine acupuncture with twirling reinforcing and reducing manipulation of the needle (RA) both at Zusanli point (St 36) on volume of microcirculatory blood flow in the cerebral ... Effects of electroacupuncture (EA) and routine acupuncture with twirling reinforcing and reducing manipulation of the needle (RA) both at Zusanli point (St 36) on volume of microcirculatory blood flow in the cerebral pia mater were observed by fenestration of the cranial bone and laser Doppler microcirculatory blood flow analyser. Results showed that both RA and EA could increase the volume of microcirculatory blood flow in the cerebral pia mater; and that the increase in the EA group was superior to that in RA group. This suggests that a moderate and effective stimulation is a key to the production of a regulative effect on the organism. 展开更多
关键词 ELECTROACUPUNCTURE Acupuncture Therapy Animals blood Flow velocity Comparative Study Female Male MICROCIRCULATION Pia Mater RABBITS Research Support Non-U.S. Gov't
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个案追踪法护理对脊柱术后患者下肢股静脉血流速度及静脉血栓栓塞症的影响
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作者 荣晓旭 朱颖 +3 位作者 梁晓莉 华婷 殷瑛 陈姝珏 《护理实践与研究》 2025年第2期291-295,共5页
目的评估个案追踪法护理对脊柱术后患者下肢股静脉血流速度及静脉血栓栓塞症(VTE)的预防效果。方法将医院2020年3月—2022年3月行脊柱手术的86例患者按照组间基本特征具有可比性的原则分为观察组和对照组,每组43例。对照组患者给予常规... 目的评估个案追踪法护理对脊柱术后患者下肢股静脉血流速度及静脉血栓栓塞症(VTE)的预防效果。方法将医院2020年3月—2022年3月行脊柱手术的86例患者按照组间基本特征具有可比性的原则分为观察组和对照组,每组43例。对照组患者给予常规护理,观察组患者实施个案追踪法护理。比较两组患者下肢股静脉血流速度变化、VTE发生率、睡眠质量、日常生活能力、护理满意程度。结果双因素重复测量的方差分析结果显示,两组患者干预前、干预后3 d、干预后1周的下肢股静脉血流速度呈现先降后升趋势,时间点之间比较差异有统计学意义(P时间<0.05);观察组患者干预后3 d、干预后1周的下肢股静脉血流速度均高于对照组,差异有统计学意义(P组间<0.05);随着观察时间的延长,组间差异均高于干预前,且干预后3 d差异最大,干预后1周差异有所减少(P交互<0.05)。观察组患者VTE发生率低于对照组,组间比较差异有统计学意义(P<0.05)。干预前,两组患者匹兹堡睡眠质量指数(PSQI)、日常生活能力量表(ADL)评分比较差异无统计学意义(P>0.05);干预后,观察组患者PSQI评分低于对照组,ADL评分高于对照组,组间比较有统计学意义(P<0.05)。观察组患者护理满意程度高于对照组,组间比较有统计学意义(P<0.05)。结论采用个案追踪法护理在脊柱术后患者中应用,可提高患者的下肢股静脉血流速度,降低VTE发生率,同时改善睡眠质量,提高日常生活能力及护理满意程度。 展开更多
关键词 个案追踪法 脊柱手术 下肢股静脉血流速度 静脉血栓栓塞症 生活质量
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丹栀逍遥散联合针刺治疗卒中后抑郁
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作者 马腾 张持萍 徐伟文 《吉林中医药》 2025年第1期64-68,共5页
目的探讨丹栀逍遥散联合针刺治疗卒中后抑郁(post-stroke depression,PSD)的临床疗效及对患者脑血管血流速度、抑郁症状、神经递质水平的影响。方法选择卒中后抑郁患者108例,随机分为对照组与观察组,各54例。2组均给予卒中内科基础治疗... 目的探讨丹栀逍遥散联合针刺治疗卒中后抑郁(post-stroke depression,PSD)的临床疗效及对患者脑血管血流速度、抑郁症状、神经递质水平的影响。方法选择卒中后抑郁患者108例,随机分为对照组与观察组,各54例。2组均给予卒中内科基础治疗,指导患者进行适当康复训练。在此基础上,对照组采用草酸艾司西酞普兰片治疗,观察组在对照组基础上予丹栀逍遥散联合针刺治疗。2组均持续治疗4周。比较2组治疗4周后临床疗效结果,治疗前、治疗2周、4周后中医证候评分、抑郁症状,治疗前、治疗4周后脑血管血流速度及神经递质水平。结果治疗4周后,观察组临床疗效结果总有效率(94.44%,51/54)高于对照组(79.63%,43/54)(P<0.05)。治疗4周后,2组中医证候评分及汉密尔顿抑郁量表(HAMD)评分均低于治疗前、治疗2周后,治疗2周后低于治疗前,且治疗2周、4周后,观察组低于对照组(P<0.05)。与治疗前比较,治疗4周后,2组脑血管血流速度、血清去甲肾上腺素(NE)、多巴胺(DA)、肾上腺素(E)水平均升高,观察组高于对照组(P<0.05)。结论丹栀逍遥散联合针刺治疗卒中后抑郁患者,能够缓解抑郁症状及相关症状,改善患者脑血管血流速度、神经递质,提高临床疗效。 展开更多
关键词 卒中 抑郁 丹栀逍遥散 针刺 血流速度 抑郁症状
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