Background Smoking and other risk factors have been well known as important factors of variant angina or coronary artery spasm （CAS）. However, clinical features related to age on coronary artery spasm have been rare...Background Smoking and other risk factors have been well known as important factors of variant angina or coronary artery spasm （CAS）. However, clinical features related to age on coronary artery spasm have been rarely evaluated. Methods We evaluated 3155 consecutive patients with insignificant coronary artery lesion. Patients underwent Acetylcholine （Ach） provocation test for induction of CAS. CAS was defined as 〉 70% luminal narrowing of coronary arteries during Ach provocation test. The results of Ach provocation test were compared among age groups; 〈 45 years （Group 1）, 45-54 years （Group 2）, 55-64 years （Group 3）, and 〉_ 65 years （Group 4）. Results Older patients had higher incidence of hypertension, diabetes, but lower incidence rate of current smoking, male sex compared with younger patients. Positive Ach provocation test finding was frequently showed with aging （47.36% vs. 58.3% vs. 62.6% vs. 61.5%; P 〈 0.001）. Multivariate logistic analysis showed that age, male, and myocardial bridge were independent predictors of CAS induced by Ach provocation test. Conclusion Our present study showed that old age was independent predictor for Ach-induced significant coronary artery spasm.展开更多
Takayasu＇s arteritis （TA） is a chronic and nonspecific in- flammatory vessel disease that involves the aorta and its major branches. TA results in stenosis, occlusion or aneu- rysmal degeneration of large arteries ...Takayasu＇s arteritis （TA） is a chronic and nonspecific in- flammatory vessel disease that involves the aorta and its major branches. TA results in stenosis, occlusion or aneu- rysmal degeneration of large arteries pathologically. Al- though TA is an unusual disease, it is more commonly ob- served to occur in Asian females compared to the general population worldwide. Aortic dissection is a very rare com- plication of TA, and only a limited number of TA cases presenting with aortic dissection have been published so far.展开更多
The pressure pulsation of axial piston pump is not only an important cause of rotation speed fluctuation,vibration noise and output stability of the hydraulic system,but also the main information source for obtaining ...The pressure pulsation of axial piston pump is not only an important cause of rotation speed fluctuation,vibration noise and output stability of the hydraulic system,but also the main information source for obtaining fault information.Hydraulic system is characterized by strong noise interference,which leads to low signal-to-noise ratio(SNR)of detection signals.Therefore,it is necessary to dig deep into the system operating state information carried by pressure signals.Firstly,based on flow loss mechanism of the plunger pump,the mapping relationship between flow pulsation and pressure pulsation is analyzed.After that,the pressure signal is filtered and reconstructed based on standard Gabor transform.Finally,according to the time-domain waveform morphology of pressure signal,four characteristic indicators are proposed to analyze the characteristics of pressure fluctuations under different working conditions.The experimental results show that the standard Gabor transform can accurately extract high-order harmonics and phase frequencies of the signal.The reconstructed time-domain waveform of pressure pulsation of the axial piston pump contains a wealth of operating status information,and the characteristics of pulsation changes under various working conditions can provide a new theoretical basis and a method support for fault diagnosis and health assessment of hydraulic pumps,motors and key components.展开更多
This paper presents an experimental study on a flat plate closed loop pulsating heat pipes. It consisted of total 40 channels with square cross section （2 × 2 mm^2, 165 mm long） machined directly on an aluminum...This paper presents an experimental study on a flat plate closed loop pulsating heat pipes. It consisted of total 40 channels with square cross section （2 × 2 mm^2, 165 mm long） machined directly on an aluminum plate（180×120×3 nm^2）, which was covered by a transparent plate. The working fluid employed was ethanol. As the results, the influence parameters of thermal performance were investigated, such as filling ratio, heat load and operational orientations etc. Filling ratio was found to be a critical parameter, and its effect was rather complicated. According to its values the PHP plate could have four distinct working zones with different operational characteristics and heat transfer performance. The effect of heat load on thermal performance was found to be positive, and in general, iucrcasing the heat load would improve heat transfer performance. In order to analyze the effect of gravity on thermal performance, three different heat modes and total seven tilt angles were tested and compared. Successful operation at all orientations with respect to gravity was also achieved.展开更多
In order to interpret the physical feature of Bessho form translating-pulsating source Green function, the phase function is extracted from the integral representation and stationary-phase analysis is carried out in t...In order to interpret the physical feature of Bessho form translating-pulsating source Green function, the phase function is extracted from the integral representation and stationary-phase analysis is carried out in this paper. The complex characteristics of the integral variable and segmentation of the integral intervals are discussed in m complex plane. In θ space, the interval [-π/2+φ,-π/2+φ-iε] is dominant in the near-field flow, and there is a one-to-one correspondence between the real intervals in m space and the unsteady wave patterns in far field. If 4τ>1(τ is the Brard number), there are three kinds of propagation wave patterns such as ring-fan wave pattern, fan wave pattern and inner V wave pattern, and if 0<4τ<1, a ring wave pattern, an outer V and inner V wave pattern are presented in far field. The ring-fan or ring wave pattern corresponds to the interval [-π+α,-π/2+φ] for integral terms about k2, and the fan or outer V wave pattern and inner V wave pattern correspond to [-π+α,-π/2) and(-π/2,-π/2+φ] respectively for terms about k1. Numerical result shows that it is beneficial to decompose the unsteady wave patterns under the condition of τ≠0 by converting the integral variable θ to m. In addition, the constant-phase curve equations are derived when the source is performing only pulsating or translating.展开更多
Long-term observations of pulse and arterial blood pressure taken from a patient＇s daily self-control diary have been analyzed in the paper. The diary was kept in the morning and in the evening. It contains regular o...Long-term observations of pulse and arterial blood pressure taken from a patient＇s daily self-control diary have been analyzed in the paper. The diary was kept in the morning and in the evening. It contains regular observational data collected during over 13 years. Statistical estimates of series and their spectral responses were obtained. A difference between the morning and evening series was noted. Spectral harmonics with the period of 7 days was typical of the evening series. The morning series are characterized by a ＂lunar＂ component with the -27.35-day period. The examined series were also compared with the daily series of atmospheric pressure and daily Wolf numbers. Seasonal pulse and arterial pressure pattern and average monthly self-control tabulated data obtained during 13 years are presented in the paper.展开更多
Objective Absence of significant epicardial coronary artery disease （CAD） in patients with acute onset of chest pain and elevation of myocardial necrosis markers is occasionally observed. The aim of this study was t...Objective Absence of significant epicardial coronary artery disease （CAD） in patients with acute onset of chest pain and elevation of myocardial necrosis markers is occasionally observed. The aim of this study was to analyse the clinical characteristics and outcome of such patients with advanced age. Methods We retrospectively analysed 4,311 patients with acute onset of chest pain plus necrosis marker elevation. Two hundred and seventy two patients without CAD on angiogram （6.3%） were identified. Out of them, 50 （1.2%） patients 〉 75 years （Group Ⅰ） were compared with （1） 222 acute coronary syndrome （ACS） patients without CAD on angiogram 〈 75 years （Group Ⅱ）, and （2） 610 consecutive patients ≥ 75 years with Non-ST-elevation Myocardial Infarction （NSTEMI） undergoing percutaneous coronary intervention （Group Ⅲ）. Results Group 1 compared to Group III patients made up for more females （64.0% vs. 49.2%; P 〈 0.0001）, and had more severe anginal symptoms on presentation [Canadian Cardiovascular Society （CCS） class Ⅰ/Ⅱ, 26.0% vs. 49.8%; P = 0.02]. Group I patients also had lower troponin levels （0.62 ± 0.8 ng/mL vs. 27 ± 74 ng/mL; P 〈 0.02）, lower leukocyte count （9.4 ± 3.13 × 10^9 vs. 12 ± 5.1 × 10^9; P = 0.001 ） and better preserved left ventricular function （56.7% ± 14.3 % vs. 45% ± 1 1%; P 〈 0.0001 ）. Event-free survival （cardiac death, myocardial infarction, recurrent angina, and re-hospitalisation） was more frequent in Group Ⅰ and Ⅱ patients compared to Group III patients （64.9%, 66.7%, and 41.6%, respectively; P 〈 0.0001）. Conclusions ACS in patients 〉 75 years without CAD is very infrequent, associated with a （1） similar outcome compared to ACS patients 〈 75 years without CAD, and （2） significant better outcome compared to NSTEMI patients 〉 75 years.展开更多
Objective:To study the effect of vascular endothelial growth factor(VEGF)and anti-VEGF on the expression of fracture healing-related factors and observe pathological changes at fractured sites. Methods:Fracture models...Objective:To study the effect of vascular endothelial growth factor(VEGF)and anti-VEGF on the expression of fracture healing-related factors and observe pathological changes at fractured sites. Methods:Fracture models were established in 105 New Zealand white rabbits and they were randomly divided into control group,VEGF group and anti-VEGF group. The relevant factors expression at fractured sites was assayed and pathological changes were observed in decalcified samples at 8,24,72 hours and 1,3,5,8 weeks after fracture. Results:After application of VGEF,the expression of BMP appeared earlier and expression time lasted longer. On the contrary,anti-VEGF completely inhibited the expression of BMP.The fractured sites were filled with fibrous callus,cartilaginous callus and bony callus at the 3rd week and woven bone was constructed at the 5th week. Fracture healing was accomplished at the 8th week in VEGF group.In anti-VEGF polyclonal antibody group, cellular necrosis increased at early period.Continuous focal necrosis was seen in the fractured sites from the 1st week to 5th week.Vascularization reduced obviously at the 3rd week. Conclusions:Fracture healing is a result of mutual regulation and coordination among many factors.VEGF may be an important factor in fracture healing.展开更多
Dear Editor,Berry syndrome is a rare combination of congenital cardiac malformations characterized by four abnormal features;namely,an aortopulmonary window(APW),aortic origin of the right pulmonary artery,hypoplasia ...Dear Editor,Berry syndrome is a rare combination of congenital cardiac malformations characterized by four abnormal features;namely,an aortopulmonary window(APW),aortic origin of the right pulmonary artery,hypoplasia or interruption of the aortic arch,with an intact ventricular septum.The disease was first reported by Berry in 1982,who estimated the incidence within the population with congenital cardiac malformations to be 0.046%(Berry et al.,1982).Until recently,展开更多
Objective: To analyze the features, diagnosis and treatment of limb arterial injuries caused by traffic accidents. Methods: A total of 43 patients with limb arterial injury admitted in our department over the past 30 ...Objective: To analyze the features, diagnosis and treatment of limb arterial injuries caused by traffic accidents. Methods: A total of 43 patients with limb arterial injury admitted in our department over the past 30 years (about 50% of them happened during the last 10 years) were analyzed retrospectively in this article. The popliteal, femoral and brachial arteries were mainly involved, accounting for 43.2 %, 20.5 % and 20.5 % respectively of all the involvements. There were 35 cases of open injury and 9 of close injury. The involved vessels were transected in 43.2 % of the cases and contused in 40.9 %. All the patients had various complications, such as fractures, dislocations and severe soft tissue injuries. The injured vessels were repaired by means of end to end anastomosis in 10 cases, autogenous vein graft in 23 cases and intraluminal hydraulic dilatation in 4 cases. Results: Successful limb salvage was achieved in 34 cases initially, whereas 10 amputations were carried out due to injuries to popliteal arteries in 7, femoral arteries in 2 and humeral artery in 1 and severe soft tissue damages in 9 cases. Twenty nine patients were followed up for 1 156 months, with the average of 48.8 months. There was good circulation in 22 cases and certain ischemia in 5 cases. Two amputations were carried out in the late stage because of popliteal artery thrombosis after repair in 2 cases. There was no death in this series. Conclusions: The limb arterial injuries caused by traffic accidents are severe and complicated. It is proposed that particular attentions should be paid to the features in diagnosis and treatment for this type of injury and special efforts should be made for both life saving and limb salvage.展开更多
The assessment and management of early-stage atherosclerosis are important for the prevention of cardiovascular disease(CVD).In this study,we used multi-contrast magnetic resonance imaging(MRI) to investigate the caro...The assessment and management of early-stage atherosclerosis are important for the prevention of cardiovascular disease(CVD).In this study,we used multi-contrast magnetic resonance imaging(MRI) to investigate the carotid plaque feature in asymptomatic,at-risk subjects;we also evaluated the correlation between MRI findings and Framingham risk score(FRS).One hundred sixty-six asymptomatic individuals with risk factors for CVD underwent multi-contrast MRI.After the arterial morphology and plaque components were outlined,the differences in carotid plaque burden among the various risk categories were analyzed.The FRS analysis showed that high-risk individuals had thicker vessel wall and higher plaque lipid content than did low risk participants.A substantial proportion of advanced carotid plaques occurred in low and intermediate-risk groups.Multi-contrast MRI may provide incremental value to the FRS in managing asymptomatic at-risk population.展开更多
文摘Background Smoking and other risk factors have been well known as important factors of variant angina or coronary artery spasm （CAS）. However, clinical features related to age on coronary artery spasm have been rarely evaluated. Methods We evaluated 3155 consecutive patients with insignificant coronary artery lesion. Patients underwent Acetylcholine （Ach） provocation test for induction of CAS. CAS was defined as 〉 70% luminal narrowing of coronary arteries during Ach provocation test. The results of Ach provocation test were compared among age groups; 〈 45 years （Group 1）, 45-54 years （Group 2）, 55-64 years （Group 3）, and 〉_ 65 years （Group 4）. Results Older patients had higher incidence of hypertension, diabetes, but lower incidence rate of current smoking, male sex compared with younger patients. Positive Ach provocation test finding was frequently showed with aging （47.36% vs. 58.3% vs. 62.6% vs. 61.5%; P 〈 0.001）. Multivariate logistic analysis showed that age, male, and myocardial bridge were independent predictors of CAS induced by Ach provocation test. Conclusion Our present study showed that old age was independent predictor for Ach-induced significant coronary artery spasm.
文摘Takayasu＇s arteritis （TA） is a chronic and nonspecific in- flammatory vessel disease that involves the aorta and its major branches. TA results in stenosis, occlusion or aneu- rysmal degeneration of large arteries pathologically. Al- though TA is an unusual disease, it is more commonly ob- served to occur in Asian females compared to the general population worldwide. Aortic dissection is a very rare com- plication of TA, and only a limited number of TA cases presenting with aortic dissection have been published so far.
基金National Natural Science Foundation of China(No.51675399)。
文摘The pressure pulsation of axial piston pump is not only an important cause of rotation speed fluctuation,vibration noise and output stability of the hydraulic system,but also the main information source for obtaining fault information.Hydraulic system is characterized by strong noise interference,which leads to low signal-to-noise ratio(SNR)of detection signals.Therefore,it is necessary to dig deep into the system operating state information carried by pressure signals.Firstly,based on flow loss mechanism of the plunger pump,the mapping relationship between flow pulsation and pressure pulsation is analyzed.After that,the pressure signal is filtered and reconstructed based on standard Gabor transform.Finally,according to the time-domain waveform morphology of pressure signal,four characteristic indicators are proposed to analyze the characteristics of pressure fluctuations under different working conditions.The experimental results show that the standard Gabor transform can accurately extract high-order harmonics and phase frequencies of the signal.The reconstructed time-domain waveform of pressure pulsation of the axial piston pump contains a wealth of operating status information,and the characteristics of pulsation changes under various working conditions can provide a new theoretical basis and a method support for fault diagnosis and health assessment of hydraulic pumps,motors and key components.
基金Supported by the Ger man National Science Foundation (DFG)(No. GR412/33)
文摘This paper presents an experimental study on a flat plate closed loop pulsating heat pipes. It consisted of total 40 channels with square cross section （2 × 2 mm^2, 165 mm long） machined directly on an aluminum plate（180×120×3 nm^2）, which was covered by a transparent plate. The working fluid employed was ethanol. As the results, the influence parameters of thermal performance were investigated, such as filling ratio, heat load and operational orientations etc. Filling ratio was found to be a critical parameter, and its effect was rather complicated. According to its values the PHP plate could have four distinct working zones with different operational characteristics and heat transfer performance. The effect of heat load on thermal performance was found to be positive, and in general, iucrcasing the heat load would improve heat transfer performance. In order to analyze the effect of gravity on thermal performance, three different heat modes and total seven tilt angles were tested and compared. Successful operation at all orientations with respect to gravity was also achieved.
基金financial support from the National Natural Science Foundation of China under Grant No. 50879090the Key Program of Hydrodynamics of China under Grant No.9140A14030712JB11044
文摘In order to interpret the physical feature of Bessho form translating-pulsating source Green function, the phase function is extracted from the integral representation and stationary-phase analysis is carried out in this paper. The complex characteristics of the integral variable and segmentation of the integral intervals are discussed in m complex plane. In θ space, the interval [-π/2+φ,-π/2+φ-iε] is dominant in the near-field flow, and there is a one-to-one correspondence between the real intervals in m space and the unsteady wave patterns in far field. If 4τ>1(τ is the Brard number), there are three kinds of propagation wave patterns such as ring-fan wave pattern, fan wave pattern and inner V wave pattern, and if 0<4τ<1, a ring wave pattern, an outer V and inner V wave pattern are presented in far field. The ring-fan or ring wave pattern corresponds to the interval [-π+α,-π/2+φ] for integral terms about k2, and the fan or outer V wave pattern and inner V wave pattern correspond to [-π+α,-π/2) and(-π/2,-π/2+φ] respectively for terms about k1. Numerical result shows that it is beneficial to decompose the unsteady wave patterns under the condition of τ≠0 by converting the integral variable θ to m. In addition, the constant-phase curve equations are derived when the source is performing only pulsating or translating.
文摘Long-term observations of pulse and arterial blood pressure taken from a patient＇s daily self-control diary have been analyzed in the paper. The diary was kept in the morning and in the evening. It contains regular observational data collected during over 13 years. Statistical estimates of series and their spectral responses were obtained. A difference between the morning and evening series was noted. Spectral harmonics with the period of 7 days was typical of the evening series. The morning series are characterized by a ＂lunar＂ component with the -27.35-day period. The examined series were also compared with the daily series of atmospheric pressure and daily Wolf numbers. Seasonal pulse and arterial pressure pattern and average monthly self-control tabulated data obtained during 13 years are presented in the paper.
文摘Objective Absence of significant epicardial coronary artery disease （CAD） in patients with acute onset of chest pain and elevation of myocardial necrosis markers is occasionally observed. The aim of this study was to analyse the clinical characteristics and outcome of such patients with advanced age. Methods We retrospectively analysed 4,311 patients with acute onset of chest pain plus necrosis marker elevation. Two hundred and seventy two patients without CAD on angiogram （6.3%） were identified. Out of them, 50 （1.2%） patients 〉 75 years （Group Ⅰ） were compared with （1） 222 acute coronary syndrome （ACS） patients without CAD on angiogram 〈 75 years （Group Ⅱ）, and （2） 610 consecutive patients ≥ 75 years with Non-ST-elevation Myocardial Infarction （NSTEMI） undergoing percutaneous coronary intervention （Group Ⅲ）. Results Group 1 compared to Group III patients made up for more females （64.0% vs. 49.2%; P 〈 0.0001）, and had more severe anginal symptoms on presentation [Canadian Cardiovascular Society （CCS） class Ⅰ/Ⅱ, 26.0% vs. 49.8%; P = 0.02]. Group I patients also had lower troponin levels （0.62 ± 0.8 ng/mL vs. 27 ± 74 ng/mL; P 〈 0.02）, lower leukocyte count （9.4 ± 3.13 × 10^9 vs. 12 ± 5.1 × 10^9; P = 0.001 ） and better preserved left ventricular function （56.7% ± 14.3 % vs. 45% ± 1 1%; P 〈 0.0001 ）. Event-free survival （cardiac death, myocardial infarction, recurrent angina, and re-hospitalisation） was more frequent in Group Ⅰ and Ⅱ patients compared to Group III patients （64.9%, 66.7%, and 41.6%, respectively; P 〈 0.0001）. Conclusions ACS in patients 〉 75 years without CAD is very infrequent, associated with a （1） similar outcome compared to ACS patients 〈 75 years without CAD, and （2） significant better outcome compared to NSTEMI patients 〉 75 years.
基金Special Funds for Major State Basic Research Projects of China(G1999054204).
文摘Objective:To study the effect of vascular endothelial growth factor(VEGF)and anti-VEGF on the expression of fracture healing-related factors and observe pathological changes at fractured sites. Methods:Fracture models were established in 105 New Zealand white rabbits and they were randomly divided into control group,VEGF group and anti-VEGF group. The relevant factors expression at fractured sites was assayed and pathological changes were observed in decalcified samples at 8,24,72 hours and 1,3,5,8 weeks after fracture. Results:After application of VGEF,the expression of BMP appeared earlier and expression time lasted longer. On the contrary,anti-VEGF completely inhibited the expression of BMP.The fractured sites were filled with fibrous callus,cartilaginous callus and bony callus at the 3rd week and woven bone was constructed at the 5th week. Fracture healing was accomplished at the 8th week in VEGF group.In anti-VEGF polyclonal antibody group, cellular necrosis increased at early period.Continuous focal necrosis was seen in the fractured sites from the 1st week to 5th week.Vascularization reduced obviously at the 3rd week. Conclusions:Fracture healing is a result of mutual regulation and coordination among many factors.VEGF may be an important factor in fracture healing.
文摘Dear Editor,Berry syndrome is a rare combination of congenital cardiac malformations characterized by four abnormal features;namely,an aortopulmonary window(APW),aortic origin of the right pulmonary artery,hypoplasia or interruption of the aortic arch,with an intact ventricular septum.The disease was first reported by Berry in 1982,who estimated the incidence within the population with congenital cardiac malformations to be 0.046%(Berry et al.,1982).Until recently,
文摘Objective: To analyze the features, diagnosis and treatment of limb arterial injuries caused by traffic accidents. Methods: A total of 43 patients with limb arterial injury admitted in our department over the past 30 years (about 50% of them happened during the last 10 years) were analyzed retrospectively in this article. The popliteal, femoral and brachial arteries were mainly involved, accounting for 43.2 %, 20.5 % and 20.5 % respectively of all the involvements. There were 35 cases of open injury and 9 of close injury. The involved vessels were transected in 43.2 % of the cases and contused in 40.9 %. All the patients had various complications, such as fractures, dislocations and severe soft tissue injuries. The injured vessels were repaired by means of end to end anastomosis in 10 cases, autogenous vein graft in 23 cases and intraluminal hydraulic dilatation in 4 cases. Results: Successful limb salvage was achieved in 34 cases initially, whereas 10 amputations were carried out due to injuries to popliteal arteries in 7, femoral arteries in 2 and humeral artery in 1 and severe soft tissue damages in 9 cases. Twenty nine patients were followed up for 1 156 months, with the average of 48.8 months. There was good circulation in 22 cases and certain ischemia in 5 cases. Two amputations were carried out in the late stage because of popliteal artery thrombosis after repair in 2 cases. There was no death in this series. Conclusions: The limb arterial injuries caused by traffic accidents are severe and complicated. It is proposed that particular attentions should be paid to the features in diagnosis and treatment for this type of injury and special efforts should be made for both life saving and limb salvage.
文摘The assessment and management of early-stage atherosclerosis are important for the prevention of cardiovascular disease(CVD).In this study,we used multi-contrast magnetic resonance imaging(MRI) to investigate the carotid plaque feature in asymptomatic,at-risk subjects;we also evaluated the correlation between MRI findings and Framingham risk score(FRS).One hundred sixty-six asymptomatic individuals with risk factors for CVD underwent multi-contrast MRI.After the arterial morphology and plaque components were outlined,the differences in carotid plaque burden among the various risk categories were analyzed.The FRS analysis showed that high-risk individuals had thicker vessel wall and higher plaque lipid content than did low risk participants.A substantial proportion of advanced carotid plaques occurred in low and intermediate-risk groups.Multi-contrast MRI may provide incremental value to the FRS in managing asymptomatic at-risk population.
