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1.
B Stephen  P Dalal  M Berger  P Schweitzer  S Hecht 《Chest》1999,116(1):73-77
OBJECTIVES: The purpose of this study was to determine whether Doppler echocardiographic assessment of right ventricular pressure at the time of pulmonary valve opening could predict pulmonary artery diastolic pressure. BACKGROUND: Doppler echocardiography has been used to estimate right ventricular systolic pressure noninvasively. Because right ventricular and pulmonary artery diastolic pressure are equal at the time of pulmonary valve opening, Doppler echocardiographic estimation of right ventricular pressure at this point might provide an estimate of pulmonary artery diastolic pressure. METHODS: We studied 31 patients who underwent right heart catheterization and had tricuspid regurgitation. Pulmonary flow velocity was recorded by pulsed wave Doppler echocardiography, and tricuspid regurgitant velocity was recorded by continuous wave Doppler echocardiography. The time of pulmonary valve opening was determined as the onset of systolic flow in the pulmonary artery. Tricuspid velocity at the time of pulmonary valve opening was measured by superimposing the interval between the onset of the QRS complex on the ECG and the onset of pulmonary flow on the tricuspid regurgitant envelope. The tricuspid gradient at this instant was calculated from the measured tricuspid velocity using the Bernoulli equation. This gradient was compared to the pulmonary artery diastolic pressure obtained by right heart catheterization. MEASUREMENTS AND RESULTS: The pressure gradient between the right atrium and right ventricle obtained at the time of pulmonary valve opening ranged from 9 to 31 mm Hg (mean, 19+/-5) and correlated closely with invasively measured pulmonary artery diastolic pressure (range, 9 to 36 mm Hg; mean, 21+/-7 mm Hg; r = 0.92; SEE, 1.9 mm Hg). CONCLUSION: Doppler echocardiographic measurement of right ventricular pressure at the time of pulmonary valve opening is a reliable noninvasive method for estimating pulmonary diastolic pressure.  相似文献   

2.
A rare case of isolated tricuspid regurgitation (TR) in a 65-year-old man is presented. Echocardiography revealed enlargement of the right atrium, dilatation of the tricuspid valve annulus without thickening or prolapse of the leaflets, and an intact atrial septum. No downward displacement of the tricuspid septal leaflet was observed by echocardiography. Mild mitral regurgitation and severe TR were detected on color flow Doppler studies. Cardiac catheterization indicated elevated right atrial pressure, with a pronounced V-wave. No left-to-right shunt was detected at the right atrium. At surgery, severe annular dilatation of the tricuspid valve (without organically diseased or deformed tricuspid leaflets) was observed, and tricuspid annuloplasty with a prosthetic ring performed. Postoperative echocardiography and right ventriculography showed trivial TR.  相似文献   

3.
By Doppler echocardiography, the performance of heart valve prostheses is assessed with the aid of maximal transprosthetic velocities, which, however, may not be representative for the full spatial velocity profile in the vicinity of mechanical valve substitutes due to flow separation by the open occluder. The purpose of this study was to determine characteristics of velocity profiles downstream of a normally functioning Bj?rk-Shiley prosthesis. In a pulsatile flow apparatus, different flow rates of 6.3 and 8.4 l/min were delivered. Using a spatially and temporally resolving ultrasonic Doppler method, velocity profiles 20 and 30 mm distal from the prosthesis were registered and displayed in a three-dimensional grid. The spatial velocity profile was found to deviate substantially from a flat profile at these transducer positions at the two flow conditions. Distal to the minor orifice, velocities measured only 70 and 80% of those downstream of the major orifice. In between, a region of relatively slow moving flow was present. The shape of the profiles remained essentially unchanged during acceleration and deceleration of flow. Thus, spatially resolved velocity profiles downstream of mechanical prostheses can be registered by an ultrasonic Doppler device. These findings may be useful for the detection of beginning malfunction both in the experimental and the clinical setting.  相似文献   

4.
Three patients with normal hearts and no pulmonary abnormality had neonatal tricuspid regurgitation causing cardiorespiratory distress and cyanosis. The signs of tricuspid regurgitation resolved over a few weeks. In the acute phase echocardiography showed gross dilatation of the right atrium and ventricle. The interatrial septum bulged into the left atrium during the whole cardiac cycle. Doppler echocardiography showed clinically significant tricuspid regurgitation, a right to left shunt through the foramen ovale, reduced flow through the pulmonary valve, and in two patients ductal flow into the pulmonary artery. In one patient tricuspid regurgitation was so great that it impeded the opening of the pulmonary valve and produced functional "atresia" of the pulmonary valve. The presence of regurgitant blood flow through the pulmonary valve showed that the "atresia" was functional rather than organic. Doppler echocardiographic study is useful in distinguishing functional neonatal tricuspid regurgitation from structural abnormality of the tricuspid valve.  相似文献   

5.
Three patients with normal hearts and no pulmonary abnormality had neonatal tricuspid regurgitation causing cardiorespiratory distress and cyanosis. The signs of tricuspid regurgitation resolved over a few weeks. In the acute phase echocardiography showed gross dilatation of the right atrium and ventricle. The interatrial septum bulged into the left atrium during the whole cardiac cycle. Doppler echocardiography showed clinically significant tricuspid regurgitation, a right to left shunt through the foramen ovale, reduced flow through the pulmonary valve, and in two patients ductal flow into the pulmonary artery. In one patient tricuspid regurgitation was so great that it impeded the opening of the pulmonary valve and produced functional "atresia" of the pulmonary valve. The presence of regurgitant blood flow through the pulmonary valve showed that the "atresia" was functional rather than organic. Doppler echocardiographic study is useful in distinguishing functional neonatal tricuspid regurgitation from structural abnormality of the tricuspid valve.  相似文献   

6.
The number of patients with atrial septal defect (ASD) who undergo intracardiac repair without cardiac catheterization has been increasing. A noninvasive quantitative method to estimate the Qp/Qs ratio in this disease is therefore needed, but no simple, accurate method has yet been reported. The purpose of this study was to devise a new clinically useful method. Study materials consisted of 15 patients with ASD who were catheterized and five post-operative patients. For this study a multigated Doppler echocardiographic instrument (Fujitsu ME 120A) was used, which allowed us to ascertain Doppler shift frequency at 64 consecutive sampling volumes up to 13 cm in depth simultaneously. In the parasternal four-chamber view, the cursor was set so as to cross obliquely the right ventricular inflow tract just below the tricuspid valve and the left atrium, just above the mitral valve. Two blood flow profiles were obtained from the flow crossing the tricuspid and mitral valves. The multigated Doppler echocardiogram was recorded on videotape and then analyzed. (1) The encircling area between the profile and the base line was measured for tricuspid and mitral flow independently throughout diastole. After summing up each area of tricuspid (TA) and mitral (MA) flow profiles, the ratio TA/MA was obtained (area calculation method). (2) The flow volume passing through each tricuspid (TF) and mitral valve (MF) was calculated from the flow profile using the "ring approach" reported by Jenni, and the ratio TF/MF was obtained (flow calculation method).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

7.
Since 1985, we have evaluated secondary tricuspid regurgitation associated with acquired mitral valve disease in patients undergoing open mitral surgery by intraoperative epicardial two-dimensional and pulsed Doppler echocardiography. We found intraoperative pulsed Doppler echocardiography to be a sensitive, safe technique allowing surgeons to evaluate the severity of tricuspid regurgitation intraoperatively, even in critically ill patients who cannot afford preoperative cardiac catheterization. To assess the severity of tricuspid regurgitation intraoperatively, the transducer was placed directly on the right atrium. The ultrasound beam was transmitted into the right atrium at right angles to the tricuspid valve orifice to record intraoperative four-chamber two-dimensional echocardiograms, which were used to detect the sites of eight sample volumes, one in the right ventricle and seven in the right atrium, for pulsed Doppler echocardiography. The pulsed Doppler signals were recorded in each sample volume before and after cardiac procedures. The pansystolic abnormal signals lasting from tricuspid valve closure to the subsequent opening and consisting of components moving away from the tricuspid valve were interpreted as tricuspid regurgitant flows. Without operative correction of the tricuspid valve, secondary tricuspid regurgitation can resolve following mitral valve surgery alone. However, to our knowledge, there are no published reports of objective findings of intraoperative changes of secondary tricuspid regurgitation. Here we present the unique intraoperative pulsed Doppler echocardiographic features of tricuspid regurgitation before and after cardiac procedures. A 30-year-old woman with preoperative diagnosis of aortic regurgitation, mitral stenosis and severe tricuspid regurgitation underwent aortic and mitral valve replacement. The intraoperative pulsed Doppler echocardiograms recorded after pericardiotomy and before cannulation of the heart showed tricuspid regurgitant flow signal in all of the seven sample volumes in the right atrium, which was interpreted as severe tricuspid regurgitation. After surgical procedures, no regurgitant flow from the tricuspid orifice to the right atrium was detected in the eight sample volumes. This suggested that preoperative secondary tricuspid regurgitation improves without operative procedures for the tricuspid valve. All intraoperative echocardiographic procedures were performed within 5 min, and no arrhythmias or other complications related to this technique were noted. Epicardial pulsed Doppler echocardiography is helpful in assessing tricuspid valve function of patients undergoing mitral valve surgery bef  相似文献   

8.
Doppler echocardiographic evaluation of the normal human fetal heart   总被引:4,自引:0,他引:4  
Pulsed wave Doppler estimates of blood flow velocity were made across the mitral, tricuspid, aortic, and pulmonary valves in a series of 120 normal fetuses (gestational age 16-36 weeks). In 36 of these the data were obtained in all four sites. The maximum and mean velocities were calculated for each valve and these values were plotted against gestational age. There was little change in these values throughout pregnancy. The orifice dimensions of the valves were measured by cross sectional echocardiography. At all ages the tricuspid orifice was larger than the mitral and the pulmonary orifice was larger than the aortic. The blood flow values for each valve were derived from the product of the mean velocity and the valve orifice dimensions. The output of the right ventricle was usually, but not always, greater than that of the left ventricle. Combined ventricular output increased from approximately 50 ml/min at 18 weeks to 1200 ml/min at term. Despite limitations in the accuracy of the technique these results form a useful basis for the analysis of blood flow in the normal fetus and for the interpretation of abnormal Doppler findings in prenatal life.  相似文献   

9.
Pulsed wave Doppler estimates of blood flow velocity were made across the mitral, tricuspid, aortic, and pulmonary valves in a series of 120 normal fetuses (gestational age 16-36 weeks). In 36 of these the data were obtained in all four sites. The maximum and mean velocities were calculated for each valve and these values were plotted against gestational age. There was little change in these values throughout pregnancy. The orifice dimensions of the valves were measured by cross sectional echocardiography. At all ages the tricuspid orifice was larger than the mitral and the pulmonary orifice was larger than the aortic. The blood flow values for each valve were derived from the product of the mean velocity and the valve orifice dimensions. The output of the right ventricle was usually, but not always, greater than that of the left ventricle. Combined ventricular output increased from approximately 50 ml/min at 18 weeks to 1200 ml/min at term. Despite limitations in the accuracy of the technique these results form a useful basis for the analysis of blood flow in the normal fetus and for the interpretation of abnormal Doppler findings in prenatal life.  相似文献   

10.
Summary We observed instantaneous blood flow velocity profiles at the right and left ventricular outflow tracts, the ascending aorta, and the lower thoracic aorta in human subjects using a newly devised method of real-time multichannel Doppler echocardiography. In 20 apparently healthy subjects, the blood flow velocity profile was successfully obtained in all cases at the right and left ventricular outflow tracts—in 13 cases at the ascending aorta, in 12 cases at the aortic arch, and in ten cases at the lower thoracic aorta. The configuration of the profile was almost flat during systole at the left ventricular outflow tract, the ascending aorta, and the descending aorta. The profile was triangular at the right ventricular outflow tract, where the velocity was faster at the ventricular septal side than at the free wall side, and it was also triangular at the aortic arch, where the velocity was faster at the inner side of the arch than at the outer side. These observations were very similar to those reported by others in previous experimental studies. Thus, the present study demonstrates that it is possible to record nonivasively the instantaneous blood flow velocity profile in humans using this new Doppler echocardiographic instrument.  相似文献   

11.
W A Zoghbi  M A Quinones 《Herz》1986,11(5):258-268
Doppler echocardiography enables noninvasive determination of blood velocity and flow area through which quantitation of blood flow in vessels and across valvular orifices can be achieved. The stroke volume is rendered as the product of the flow area and the area beneath the velocity curve; on taking the heart rate into consideration, the cardiac output can be calculated. Essentially, this method can be used in the region of all four cardiac valves, the ascending aorta and the pulmonary artery. For calculation of the mitral and tricuspid velocity, the sample volume is positioned in the region of the tips of the leaflets or in the valve anulus. The flow area is most frequently calculated from the diameter of the valve anulus under the assumption of a circular cross-section. Additionally, in some studies, with respect to correction for area changes during diastole, separation of the leaflets in the M-mode echocardiogram has been employed. Determination of the right ventricular output is accomplished through the combination of the blood flow velocity in the pulmonary artery and the cross-sectional area of this vessel, the right ventricular outflow tract or the pulmonic anulus. To calculate flow in the ascending aorta, both pulsed and continuous-wave Doppler techniques have been employed and the diameter of the ascending aorta or the aortic root is derived echocardiographically. Comparative studies of the various methods show that measurement of flow in the region of the aortic anulus yields results somewhat superior to that of the other methods. Possible sources of error in these methods result from simplifying assumptions with respect to calculation of the area of flow, that is, equating the anatomical area with the area of flow, circular or elliptical cross-sectional models, temporal constancy of the areas as well as the velocities, that is, constant position of the sample volume, flat velocity profile and neglect of angle deviations.  相似文献   

12.
BACKGROUND: Until now no diagnostic technique was available for the three-dimensional (3D) study of intracardiac blood flow abnormalities in patients with heart valve disease. 3D color Doppler is a new diagnostic technique first developed at our institution. METHODS: The 3D reconstructions of the blood flow velocity data have been obtained from conventional multiplanar transesophageal or transthoracic Doppler echocardiographic examinations. We analyzed 111 reconstructions of color Doppler data obtained from 85 patients with different heart valve diseases who underwent intraoperative transesophageal echocardiography. Sixty-nine patients had a significant mitral regurgitation, 7 mitral stenosis, 9 aortic regurgitation, 12 aortic stenosis, 14 tricuspid regurgitation. Three patients had pulmonary regurgitation associated with mitral valve disease. RESULTS: 3D color Doppler disclosed the complex spatial spreading of the blood flow abnormalities caused by heart valve disease. New patterns of intracardiac blood flow disturbances could be observed and classified. CONCLUSIONS: This paper shows the first clinical applications of 3D color Doppler in patients with heart valve disease. The new insights derived from the 3D study of intracardiac blood flow dynamics revealed a great impact of this technique on the clinical management of patients with heart valve disease.  相似文献   

13.
Pulsed Doppler echocardiography may allow noninvasive detection of tricuspid insufficiency as disturbed or turbulent systolic flow in the right atrium and pulmonary insufficiency as turbulent diastolic flow in the right ventricular outflow tract. Accordingly, six open chest mongrel dogs were examined with Doppler echocardiography before and after surgical creation of tricuspid and pulmonary insufficiency. The Doppler technique detected the appropriate lesion in all instances, with a specificity of 100 percent.In 121 patients (20 without heart disease, 101 with heart disease of various causes), pulsed Doppler echocardiography was used to detect right-sided valve regurgitation. Results were compared with right-sided pressure measurements and M mode echocardiographic findings in all, and with right ventricular angiography in 21 patients. Pulsed Doppler study detected tricuspid insufficiency in 61 of 100 patients, 12 (20 percent) of whom had clinical evidence of this lesion. Angiographic evidence of tricuspid regurgitation was present in 18 patients, 17 of whom had positive Doppler findings (sensitivity 94 percent), and absent in 3, all with negative Doppler findings. Pulmonary insufficiency was found on pulsed Doppler study in 47 of 91 patients, 3 of whom (all after pulmonary valvotomy) had clinical evidence of this lesion. Increased right ventricular systolic pressure (greater than 35 mm Hg) was noted more often in patients with (55 of 61 or 90 percent) than in those without (22 of 59 or 37 percent) tricuspid insufficiency (p <0.01). Pulmonary arterial mean pressure was elevated (22 mm Hg or less) more often in patients with (38 of 43 or 88 percent) than in those without (24 of 64 or 38 percent) pulmonary insufficiency (p <0.01).Thus, pulsed Doppler echocardiography appears to be an accurate noninvasive technique for detection of right-sided valve regurgitation. The absence of diagnostic physical findings in many of the patients indicates that the hemodynamic severity of the Doppler-detected valve insufficiency was probably insignificant. However, because of its high incidence rate (87 percent) and association with pulmonary hypertension (87 percent), pulsed Doppler detection of tricuspid or pulmonary insufficiency, or both (in the absence of pulmonary stenosis) was found superior to M mode echocardiographic measurements (right ventricular size, pulmonary valve motion) in the prediction of pulmonary hypertension.  相似文献   

14.
The pattern of normal blood flow in the right atrial cavity was studied using the newly developed real-time two-dimensional Doppler flow imaging technique as a standard reference for the Doppler diagnosis of heart diseases with intracardiac shunts at the atrial level. The study was performed primarily with use of the apical four chamber and the parasternal right ventricular inflow tract views in 21 healthy subjects. The following patterns were observed: blood from the inferior vena cava flowed up along the posterior wall of the right atrium and joined with blood from the superior vena cava in the posterocranial part of the right atrial cavity; the flow then coursed along the roof of the right atrium toward the tricuspid valve in the atrial relaxation phase. This flow was always noted along the interatrial septum in the four chamber view. During and after mid-systole of the right ventricle, additional blood flow away from the tricuspid valve appeared, moving from the valve to the central part of the right atrial cavity, that is, at the lower right of the preceding inflow; this flow was interpreted as arising from eddy currents caused by the preceding inflow. In early diastole of the right ventricle, the flow signal area along the interatrial septum and the roof of the right atrium extended into the right ventricular cavity through the tricuspid valve. In the atrial contraction phase only the blood near the tricuspid valve in the right atrial cavity appeared to flow into the right ventricular cavity. Inflow from the coronary sinus was almost undetectable.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

15.
The case of a patient with right coronary artery-right atrial fistula was reported, with special reference to the noninvasive evaluation. On two-dimensional echocardiography in the short axis view, it was observed that the fistula had an entrance from the right coronary cusp, with the body of fistula sigmoid-like appearance running along the tricuspid ring and atrioventricular groove. In the subxyphoidal approach the exit of fistula into the right atrium was demonstrated. Intrafistular blood flow and drainage flow into the right atrium were identified by color flow mapping. The potential usefulness of the combination of two-dimensional, pulsed Doppler echocardiography and color flow mapping were discussed.  相似文献   

16.
R Jacksch  K R Karsch  L Seipel 《Herz》1986,11(6):337-340
In 187 patients with combined mitral and aortic valve lesions, to assess and quantify tricuspid regurgitation, biplane right ventriculograms were obtained and Doppler echocardiography performed for study of the tricuspid valve and right atrium. After definition of regurgitant turbulance across the tricuspid valve with pulsed Doppler, on mapping the right atrium the maximal length of regurgitant flow in the right ventricular inflow tract was determined from the short-axis parasternal view. In seven of 70 patients in whom angiographically tricuspid regurgitation was not detected, Doppler echocardiography demonstrated holosystolic insufficiency of the valve. In all patients with the angiographic diagnosis of tricuspid regurgitation grades I to III, this lesion was also documented Doppler echocardiographically with only slight divergence of the regurgitant area in the right atrium as viewed from the short-axis parasternal transducer position. In all patients, the tricuspid valve was morphologically unremarkable. In 32 patients, in agreement with angiographic findings, grade I tricuspid regurgitation was diagnosed; in seven patients the angiographic severity was overestimated by one grade. In 44 patients, in agreement with angiographic findings, tricuspid regurgitation grade II was detected; in four patients the Doppler echocardiographic severity was overestimated and five patients underestimated by one grade. In 23 patients with grade II tricuspid regurgitation angiographically, there was agreement with Doppler echocardiographic findings; in two patients the severity was underestimated by one grade.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

17.
目的探讨经胸房间隔缺损封堵术对房室瓣反流的影响。方法回顾性分析2002年1月至2011年3月在南方医科大学珠江医院经胸微创房间隔缺损堵闭术患者的临床资料,其中资料完全者43例,40例在食道超声、2例在经胸超声辅助下行房间隔缺损堵闭术。患者术前、术后1个月及6个月经超声心动图检查,观察心脏各指标的变化和房室瓣反流程度。结果41例手术成功,手术成功率95.3%(41/43);1例术中改为右侧开胸小切口体外循环下房间隔缺损修补术,1例术中并发心搏骤停。1例术后并发肾功能衰竭:12例术后即时有少量残余漏,1个月后超声复查消失。术后超声随访显示:右心室、右心房直径较前缩小,左心室直径较前增大,肺动脉瓣血流速度明显降低,差异有统计学意义(P〈0.05);室间隔厚度、二尖瓣血流速度、主动脉瓣血流速度无明显改变,差异无统计学意义(P〉0.05)。房间隔缺损堵闭术后1个月、6个月,二尖瓣瓣膜反流程度较术前加重,差异有统计学意义(平均秩次:2.01VS.2.17vs1.77,x2=10.78,P=0.04);而三尖瓣的瓣膜反流程度术前与术后1个月、6个月比较,差异无统计学意义(平均秩次:1.88vs2.11US.2.01,X2=4.23,P=0.134)。结论房间隔缺损封堵术后,可引起二尖瓣反流程度的加重,但对三尖瓣的反流程度近期影响不明显;二尖瓣中度以上或三尖瓣重度反流的患者或不适宜行单纯房间缺损封堵术。  相似文献   

18.
S T Smith  K Hautamaki  J W Lewis  J Serwin  M Alam 《Chest》1991,100(2):575-576
An asymptomatic patient was discovered to have a large right atrial myxoma by transthoracic echocardiography. Preoperative considerations included the possibility of satellite lesions, left atrial origin, and a question of tricuspid valve involvement. Subsequent operative transesophageal echocardiography demonstrated single-stalk attachment in the right atrial septal wall and no satellite lesions. Doppler and color flow examination immediately following tumor removal aided in the decision not to perform tricuspid annuloplasty as there was no significant tricuspid regurgitation. The combined use of transthoracic and transesophageal echocardiography with Doppler and color flow imaging aids in the preoperative and intraoperative diagnosis and surgical management of right atrial tumors.  相似文献   

19.
An 50 year-old asymptomatic female was admitted to preoperative cardiovascular evaluation for noncardiac surgery. Two-dimensional transthoracic echocardiography demonstrated that left ventricular dimensions and ejection fraction were normal. The mitral valve was normal both in morphology and function. The attached margin of septal and anterior leaflet of the tricuspid valve was apically displaced. But right ventricle and right atrium dimensions were normal, and Doppler interrogation showed a slight tricuspid regurgitation. Two and three-dimensional transthoracic echocardiography showed prominent numerous trabeculations in the left ventricular apex. Colour flow Doppler studies confirmed the presence of blood flow within the trabeculations. Multi-plane three-dimensional transthoracic echocardiography showed a muscular band leading to left ventricular mid-caviter narrowing. Pulse wave Doppler echocardiography demonstrated that no intraventricular gradient existed. Ventricular noncompaction associated with Ebstein's malformation has been reported. But left ventricular noncompaction and mid-caviter narrowing associated with Ebstein's anomaly have not been reported so far.  相似文献   

20.
OBJECTIVE--To study the prevalence and the characteristics of physiological valve regurgitation. DESIGN--Pulsed wave Doppler echocardiography, continuous wave Doppler echocardiography and Doppler colour flow mapping were performed prospectively in healthy volunteers. SETTING--Echocardiography laboratory in a city hospital. PATIENTS--32 consecutive healthy volunteers (age 21-49 years, mean age 29.4). MAIN OUTCOME MEASURES--Identification of regurgitation with colour Doppler flow mapping and measurement of the jet area, jet length, and maximal velocity of the regurgitation. RESULTS--Regurgitation was recorded at the pulmonary (100%), tricuspid (100%), mitral (56%), and aortic valves (6%). The velocity of pulmonary and tricuspid regurgitation was similar to that predicted from the pressure gradient calculated from the Bernoulli equation. The jet area and jet length were generally small. CONCLUSION--Trivial regurgitation from the pulmonary, tricuspid, and mitral valves is common in healthy people. It is important to take such regurgitation into account when valve disease is diagnosed.  相似文献   

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