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1.
In order to differentiate the vectorcardiogram (VCG) in high posterior infarction (HPI) from VCGs of normal subjects, right ventricular hypertrophy (RVH) and primary myocardial disease (PMD), the following criteria were presented; cases satisfying the criteria could be diagnosed as high posterior infarction. In cases with posterior component/anterior component (P/L) less than 1.0 (Group A); (1)--45 degrees vector/ab less than or equal to 0.25, (2) the maximal T vector in the horizontal plane greater than or equal to + 20 degrees, (3) I (inferior component)/L (left component) less than 1.0 and (4) no anterior convexity of the afferent limb of the left sagittal QRS loop. In cases with P/A greater than or equal to 1.0 (Group B);--45 degrees vector/ab less than or equal to 0.2, (2) the maximal T vector in the horizontal plane greater than or equal to + 20 degrees, (3) I/L less than 1.0 and (4) no anterior convexity of the affernt limb of the left sagittal QRS loop. Only one false negative case in HPI was found and only seven false positive cases in normal subjects, RVH and PMD. A correct diagnosis can be made with 97.4% accuracy. These criteria for differentiation were tested by reexamining the cases with selective coronary arteriography. Five cases satisfied the criteria of this method. Complete obstruction of the circumflex coronary artery was found in four of these cases, and severe stenosis (greater than or equal to 90%) in one case. Akinesis or hypokinesis of the posterobasal segment in the left ventricle was also observed in all five cases.  相似文献   

2.
An echocardiographic (echo), vectorcardiographic (VCG) and electrocardiographic (ECG) study of the right ventricle was carried out in 27 patients with chronic obstructive pulmonary disease and cor pulmonale. The subxiphoid echocardiographic approach was applied in all patients. The right ventricular internal diameter index (RVIDd), anterior right ventricular wall thickness (RVWT) and the ratio (R) intraventricular septum thickness/anterior right ventricular wall thickness were statistically different in the 27 patients compared to the 33 normals. All 27 patients had a RVIDd greater than 1.33 cm while in only 17 (63%, P less than 0.01) of these was right ventricular hypertrophy (RVH) detected with VCG or ECg criteria. In 20 patients the RVWT was measured and in 19 of these the RVWT was greater than 0.56 cm. In only one patient was the RVWT less than 0.56 cm. VCG or ECG criteria showed RVH in only 14 (70%) of these patients. The R was measured in 18 patients. All patients had R less than 1.99 and in only 12 (67%, P less than 0.01) of these was RVH diagnosed with VCG or ECG criteria. It seems that the RVIDd, the RVWT and the R are useful indexes for the detection of right ventricular dilatation and hypertrophy. Therefore echocardiography is superior to the conventional ECG and VCG in the recognition of right ventricular hypertrophy and dilatation.  相似文献   

3.
The differentiation of posterobasal myocardial infarction (PMI) from either right ventricular hypertrophy (RVH) or normal subjects displaying an anterior loop (AL) by electrocardiography (ECG) or vectorcardiography (VCG) is difficult. M-mode echocardiography (echo) via the anterior and subxiphoid methods has been helpful in defining cardiac chamber size and wall motion abnormalities. We tested whether this relatively more direct method would better separate these entities compared with the other two techniques. ECG and VCG using established criteria failed to distinguish the three conditions effectively. By echo, distinguishing characteristics were observed in each of the groups. Thus, right ventricular diastolic dimension and wall thickness were significantly increased only in the RVH group, echo dimensions and wall motion were normal in the AL group and the posterior left ventricular systolic thickening response and ejection phase indices were significantly reduced only by the subxiphoid method in the PMI group. To test the specificity of the latter finding, posterior wall motion in three infarction groups (posterior, combined posteroinferior and inferior) were examined and suggested that the target of the subxiphoid beam focuses on a more superior posterobasal left ventricular segment than the anteriorly placed transducer. Echocardiography can differentiate PMI from either RVH or AL more directly than ECG or VCG, and may be of practical clinical importance.  相似文献   

4.
Frank vectorcardiograms (VCGs) were reviewed in 45 patients with hypertrophic cardiomyopathy (HCM), 26 with obstruction and 19 without obstruction. Twelve of the 19 patients without obstruction and five of the 26 patients with obstruction were found to have predominantly anterior QRS loops. Fourteen patients had a large left anterior QRS loop with increased anterior and leftward force; the posterior and terminal rightward force were within the normal range, and the T loops were displaced posteriorly and to the right opposite to the QRS loop. Asymmetric septal and apical hypertrophy were noted echocardiographically and/or angiographically. Increased electrical force from the asymmetric hypertrophy of the septal and apical area is proposed to explain this large left anterior loop. Three patients had a QRS loop located anteriorly and to the right with electrocardiograms (ECGs) resembling those of posterolateral myocardial infarction or right ventricular hypertrophy. These finding suggest that (1) hypertrophic cardiomyopathy may be another cause of an anterior QRS loop; (2) the recognition of the large left anterior loop in the VCG in patients with a left ventricular hypertrophy pattern in the ECG is helpful in the diagnosis of HCM, especially the nonobstructive form; and (3) hypertrophic cardiomyopathy should be considered in the differential diagnosis of myocardial infarction or right ventricular hypertrophy.  相似文献   

5.
Characteristic electrocardiographic findings of the left septal fascicular block consist of a prominent anterior QRS force. Therefore, the following criteria were proposed for the diagnosis of left septal fascicular block, based on the normal limits of the R and S waves and R/S of V1 and V2. (1) Right ventricular hypertrophy, complete right bundle branch block, preexcitation (Type A), high posterior infarction, hypertrophic cardiomyopathy and abnormality of the thorax or intrathoracic tissues which might cause marked counterclockwise rotation around the longitudinal axis of the heart, should be excluded. (2) One of the following two criteria should be satisfied. (i) R/Sv1 greater than 2, and Rv1 greater than or equal to 5 mm, (ii) R/Sv2 greater than 2, and Rv2 greater than or equal to 15 mm, or Sv2 less than 5 mm. The frequency of left septal fascicular block diagnosed by these criteria was 3.5% among all patients of a hospital mainly consisting of elderly patients. This frequency was less than that of the left anterior fascicular block or complete right bundle branch block, but it was higher than that of the complete left bundle branch block or bilateral bundle branch block.  相似文献   

6.
Twenty-eight patients with chronic pulmonary diseases were examined with standard 12-lead electrocardiogram (ECG), vectorcardiogram (VCG), and body surface ECG mapping (MAP). The electrocardiographic findings were compared with results of 99 mTc radionuclide right ventriculography or T1-201 myocardial scintigraphy. In a stepwise multiple regression analysis between the electrocardiographic parameters and right ventricular ejection fraction, only the amplitude of the negative P wave in V2 (r = 0.69), the posterior force of P loop in VCG (r = 0.71), and the size of -2SD area at 50 msec QRS potential departure map (r = 0.55) were selected as the parameters in standard ECG, VCG, and MAP, respectively. On the radionuclide ventriculography and myocardial scintigraphy, 14 patients were judged to have right ventricular overload. The criteria by VCG, and MAP had better sensitivity and specificity for right ventricle overload than those by 12-lead ECG. VCG criteria of Chou et al had sensitivity of 93% and specificity of 71%. MAP criteria, departure index of F3 or F4 less than or equal to -2, had sensitivity of 86% and specificity of 79%. The electrocardiographic findings by standard 12-lead ECG, VCG and body surface ECG mapping are useful parameters for the noninvasive detection of right ventricular overload in patients with chronic pulmonary diseases.  相似文献   

7.
Electrocardiographic tall R waves in the right precordial leads may be present in patients with posterior myocardial infarction, right ventricular hypertrophy, various conduction disturbances, and some forms of cardiomyopathy and in clinically otherwise normal subjects with prominent anterior electromotive forces. Clinical uncertainty most often arises in distinguishing possible prior posterolateral myocardial infarction (PMI) from the unusual normal variant (PAF). The ECGs and VCGs of 15 subjects with posterolateral infarction were compared with tracings from 12 subjects with no evidence of cardiac disease, all individuals demonstrating tall R waves (R/S greater than 1.0 in V1 and/or V2) in the right precordial leads on surface ECG. By standard ECG, the infarction group was characterized by taller T waves in leads V1 and V2, shorter T waves in V6, greater T2-T6 index, and a more negative two variable function as described by Nestico. By VCG, the infarction group was characterized by a more anteriorly oriented T loop, more leftward maximal frontal plane QRS vector and a lower calculated -45 degrees/ab, as described by Suzuki. An algorithm was proposed that permitted proper classification (PAF vs. PMI) based on ECG criteria in 75% of subjects with 90% accuracy. This compared favorably with performance of the Frank vectorcardiogram, including using more recently proposed criteria. Routine use of the VCG, therefore, in this clinical setting may no longer be justified.  相似文献   

8.
Athletes often exhibit ECG findings which are considered to be abnormal. Therefore, we used noninvasive graphic methods to study 42 active professional male basketball players, ranging in age from 21 to 31 years, without clinically evident heart disease. Of the 42, 11 (25%) met the Romhilt-Estes ECG voltage criteria for left ventricular hypertrophy, and 12 (29%) satisfied VCG criteria for left ventricular enlargement; nine (21%) had left ventricular hypertrophy by both methods. In 33 subjects (79%) the 0.04 sec vector in the horizontal plane was anterior, and 29 of these exhibited one or more standard criteria for right ventricular enlargement; the ECG and VCG were concordant for right ventricular hypertrophy in 16 subjects (38%). Submaximal treadmill exercise tests (Bruce protocol) were normal in eight athletes, while in one subject ventricular premature beats occurred during the test. In 24 of 25 athletes (96%) from whom phonocardiograms were obtained a third heart sound was recorded, while in 14 (56%), a fourth heart sound was present. Of the 14 athletes who had a fourth heart sound, 12 (86%) had either ECG or VCG evidence of ventricular hypertrophy. Only four of 23 athletes had an increased cardiothoracic ratio (greater than .50) on routine chest X-ray. Ten athletes and ten control subjects matched for height, weight and body surface area had echocardiograms satisfactory for analysis. The left ventricular end-diastolic dimension in the athletes averaged 53.7 +/- 1.3 (SE) mm compared with a value of 49.9 +/- 0.7 mm in the control subjects (P less than 0.02), and was increased (greater than or equal to 56 mm) in four. Left ventricular posterior wall thickness averaged 11.1 +/- 0.6 mm, compared with a value of 9.8 +/- 0.5 mm in the control subjects (P less than 0.05), and was increased (greater than or equal to 11 mm) in six athletes. The right ventricular end-diastolic dimension averaged 20.8 +/- 1.1 mm compared with a value of 12.9 +/- 2.2 mm in the controls (P less than 0.004), and was increased (greater than or equal to 23 mm) in four athletes. No athlete or control subject exhibited paradoxical septal motion. In the athletes, ejection fraction (cube method) averaged 79 +/- 2.0% and mean Vcf averaged 1.13 +/- 0.04 circ/sec; these values did not differ from those of the control subjects. Thus, both right and left ventricular enlargement ("physiological hypertrophy") are often present in the well-trained athlete, but left ventricular performance remains normal in the basal state in such individuals. We condlude that these individuals represent a selected subgroup of subjects who are variants of normal.  相似文献   

9.
The utility of vectorcardiographic relative QRS loop area criteria in identifying significant hemodynamic abnormality (a mean pulmonary artery pressure greater than 25 mmHg and/or a pulmonary to systemic flow ratio greater than 1.5) in patients with cardiac lesions associated with selective right ventricular overload was investigated in a consecutive series of patients, 291 with Heart Disease and 135 Controls. The specificity and predictive value of individual abnormally increased right quadrant areas were greater than 90% and greater than 80%, respectively. The predictive value of an isolated increase in left anterior area greater than 70% in identifying the absence of significant hemodynamic abnormality (= 91%) was similar to a negative VCG (= 80%). False positive increases in right quadrant areas were found only in association with counterclockwise transverse plane QRS loop rotation. The predictive value of a counterclockwise loop rose from 77% to 86% by increasing the diagnostic requirement for an abnormal increase in right inferior and posterior area from 20%, respectively, to 26%, respectively.  相似文献   

10.
11.
Current electrocardiographic (ECG) criteria for diagnosing right ventricular hypertrophy (RVH) have low sensitivity. In this study maximally specific and sensitive ECG criteria for RVH due to mitral stenosis (MS) were developed that incorporated the principles derived from spatial changes in the QRS complex observed on the vectorcardiogram and any existent ECG criteria that supplement the diagnostic capability of the criteria derived from the vectorcardiogram. The standard 12-lead electrocardiograms of a control group of 500 consecutively selected subjects with 50 women and 50 men in each decade between ages 20 and 69 years were compared with the electrocardiograms of a study population of 50 patients with RVH due to MS. Inclusion criteria were a diagnosis of MS by catheterization, normal coronary arteriographic and left ventriculographic findings and no other valvular abnormalities. It was hypothesized that patients with RVH resulting from MS would have QRS forces that are maximally anterior (A) and rightward (R) and minimally posterolateral (PL); thus, the A + R - PL value in the study group would be greater than that in the control group. The subsequently derived formula criterion (A + R - PL greater than or equal to 0.7 mV) and 2 additional criteria, R less than or equal to 0.2 mV in lead I and P less than 0.25 mV in leads II, III, aVF, V1 or V2, were tested in both groups. The specificity and sensitivity of each individual criterion was determined; when combined, the criteria yielded 94% specificity and 64% sensitivity. Moderate to severe RVH due to MS was detected in two-thirds of the patients using the proposed criteria.  相似文献   

12.
An analysis of the vectorcardiogram results (VCG) in 77 cases with a posterior extension of an infarct and 31 cases with an exclusively posterior infarction (EPI) has allowed us to distinguish some diagnostic criteria relative to the extension, or localisation, of an infarct in the posterior segment. The maximum anterior vector (MAV) appears late (36.5 ms +/- 5), and the amplitude of its projection onto Z is increased; the maximum vector (V max) appears early (41.5 ms +/- 4.5), and its orientation is anterior (+ 24 degrees +/- 11); the interval separating MAV from V max is reduced to 5 ms; the transition from before backwards is late (50 ms +/- 6); the ratio of anterior surface to posterior surface is increased (1.45); there is a terminal delay, most frequently occuring in the right posterior quadrant in 78 percent of cases; and finally, the T loop approaches the Z axis. Repeat electrocardiograms in patients with EPI show the most frequent changes to be represented (in 25 cases out of 31) by the following formula: AQRS " 0 degrees, R/S greater than or equal to 1 in V2, RV2 greater than RV6. The diagnosis of an exclusively posterior infarction can therefore be made with a high degree of certainty when these electrocardiographic abnormalities are associated with the clinical picture of coronary insufficiency.  相似文献   

13.
From 81,000 ECGs we collected 83 cases that fulfilled the criteria of Interatrial Conduction Disturbances with Left Atrial Retrograde Activation (IACD-LARA) (P +/- in II, III and VF with P width greater than or equal to 120 msec.). We present the detailed study of 35 cases with surface ECG and VCG and 29 cases with orthogonal ECG leads. The results are then compared against two control groups: with cardiopathy (30 cases) and without cardiopathy (25 cases). The prevalence of IACD-LARA was nearly 1% globally, and 2% among patients with valvular heart disease. The diagnostic criteria for IACD-LARA are: 1) ECG: P +/- in II, III and VF with P greater than or equal to 120 msec. with open angle (usually greater than 90 degrees) between the first and the second part of the P.2) Orthogonal ECG: P +/- in Y lead with a negative mode greater than 40 msec. 3) VCG: More than 50 msec. above the X or Z axis, duration of the P loop greater than or equal to 110 msec., open angle between the two parts of the P loop in both frontal (131.3 degrees +/- 32.3) and right sagital planes (171.2 degrees +/- 15.1), and presence of notches and slurrings in the last part of the P loop.  相似文献   

14.
The prognostic significance of electrocardiographic "extensive right ventricular infarction" diagnosed by ST elevation greater than or equal to 1 mm in right chest leads V3R to V7R during inferior/posterior infarction was evaluated in 158 consecutive patients with first anterior (n = 72) or inferior/posterior (n = 86) myocardial infarction. At follow-up the maximum observation time was 3.0 years (mean 1.8 years). A total of 49 patients died; 96% due to cardiac causes. Twelve patients (8%) died during the first 24 hours of admission. Ten-day mortality was 18% (n = 29). Using Cox multivariate analysis ST elevation in right chest leads during inferior/posterior infarction was an independent predictor of prognosis in patients surviving the initial 10 days after infarction (n = 129). For these patients the cumulative survival was better after inferior/posterior infarction with ST elevation in V3R to V7R (n = 25) compared with (1) inferior/posterior infarction without St elevation in these leads (n = 45, P = 0.09), (2) anterior infarction (n = 59, P = 0.08), and (3) all other infarctions (n = 104, P = 0.05). Infarct size estimated by the peak serum enzyme values was similar in these groups. Thus, electrocardiographic extensive right ventricular infarction predicts a good prognosis in patients alive 10 days after infarction. Compared with infarcts of similar size but with another location the prognosis is better, probably due to concomitant smaller left ventricular infarction with better left ventricular function following infarction.  相似文献   

15.
We analyzed the VCGs of 100 young subjects without apparent cardiac disease showing an ECG superior Axis Deviation, i.e. AQRS greater than - 30 degrees, and a rS aspect in V1. Our findings demonstrated that, in these subjects, the superior axis deviation is due to a distal right bundle branch block with posterior displacement of the terminal forces in 78% of the cases. The other cases being left anterior hemiblocks, either isolated (12%) or associated with a block of the anterior subdivision of the right bundle branch (10%). The differential diagnosis, easy on VCG, is sometimes very difficult on ECG. The most reliable ECG criteria to discriminate this kind of right bundle branch block from left anterior hemiblock are: intrinsic deflection in a VL-V6 greater than or equal to 0.015" (sensitivity 100%; specificity 57%), RV6/Ra VL ratio greater than 1 (sensibility 100%; specificity 50%) and the presence of a notched R wave in L2, L3 and a VF (sensitivity 90%; specificity 100%).  相似文献   

16.
Frank lead vectorcardiograms (VCG) from four carefully selected patient subgroups (226 patients) were analyzed to develop optimal criteria for the diagnosis of anterior myocardial infarction. Specificity was evaluated using 100 healthy volunteers under age 30 and 80 patients with normal left ventriculogram and normal coronary arteriograms. Sensitivity was determined using 25 patients with evolutionary ST-T wave changes (V1-2), and LDH and CPK isoenzyme evidence of acute myocardial infarction; and 21 patients with anterior wall akinesia or dyskinesia and greater than 70% occlusion of the left anterior descending coronary artery. Patients with VCG evidence of bundle branch block, left or right ventricular hypertrophy were excluded. The criterion for the diagnosis of anterior myocardial infarction which was found to give the highest sensitivity with greater than or equal to 95% specificity was: initial anterior QRS forces must not exceed 0.1 mV in maximal anterior amplitude and also must not exceed 24 msec in duration. The performance of this proposed criterion was then tested using four similarly defined patient subgroups consisting of a total of 222 patients. The incidence of false positive diagnosis in these test subgroups was less than 1% with a sensitivity of greater than 95%. The overall performance of the proposed criterion was found to be significantly superior to both the widely accepted VCG and ECG criteria for anterior myocardial infarction. Thus, this quantitative criterion using both time and duration of initial anterior forces is both a highly specific and a sensitive indicator of anterior myocardial infarction.  相似文献   

17.
计算机心电图与计算机心向量图的联合应用   总被引:1,自引:0,他引:1  
本研究利用两个计算机自动诊断系统,一个对心电图,一个对心电向量图进行分析,完成了对国际标准心电图库的联合诊断,产观察了单独诊断之间,单独诊断与联合诊断之间的差异,以进一步探讨心电图与心电向量图在诊断上的互补效应,以及CSE研究中关于联合诊断优于单独诊断的机制。国际标准心电图库由1220个病例构成,其中正常者382例,左室肥大183例,右室肥大55例,双室肥大53例,前壁心梗170例,下壁心梗273  相似文献   

18.
P2 300 selected patients, scalar electrocardiograms and contemporaneous radionuclide angiograms were analyzed retrospectively to assess the association between prominent right precordial R waves (duration greater than or equal to 0.04 second, R greater than or equal to S in lead V1 or V2), traditionally considered diagnostic of "posterior" infarction, and asynergy in various left ventricular segments. Mathematical methods for analysis of association between nonparametric variables clearly demonstrated that prominent right precordial R waves were strongly associated with asynergy of the basal lateral left ventricular wall, although asynergy of adjacent inferior and lateral segments was common. With the exclusion of right ventricular hypertrophy and bundle branch block, a prominent R wave in lead V1 exhibited a high specificity (greater than to 99%), a high positive predictive value (91%) and a low sensitivity (36%) for diagnosing basal lateral myocardial infarction. A prominent R wave in lead V2 exhibited a higher sensitivity (61%), a somewhat lower specificity (95%) and a significantly lower positive predictive value (76%). A newly developed criterion for such infarction--a prominent R wave in lead V2 and a Q wave inferior infarction--had intermediate characteristics and may be more clinically useful. The most common reasons for the decreased sensitivities of all three criteria were left ventricular hypertrophy or associated anterior myocardial infarction. These data demonstrate that prominent right precordial R waves are clinically useful in identifying inferior and lateral wall infarctions that involve the basal lateral left ventricular segment. Confusion results primarily from inappropriate use of the electrocardiographic term "posterior" for such infarctions.  相似文献   

19.
Standard electrocardiograms (ECG) and Frank vectorcardiograms (VCG) were obtained in 43 consecutive patients in sinus rhythm who had echocardiographic evidence of left atrial enlargement (left atrial internal dimension greater than 4.0 cm; x +/- 1SD = 4.7 +/- 0.5 cm). High gain VCG P loop measurements for the study group were: maximal posterior magnitude, 0.11 +/- 0.03 mv; duration, 106 +/- 14 msec and ratio of maximal posterior to maximal anterior P vector magnitudes, 3.2 +/- 1.4. Thirty of 43 (70%) patients with echocardiographic determined left atrial enlargement had VCGs diagnostic of that condition. Utilizing New York Heart Association criteria for left atrial enlargement, 17 of 43 patients (40%) had ECGs which were diagnostic. Fifteen of 43 (35%) subjects manifested both ECG and VCG criteria for left atrial enlargement and only two patients had diagnostic ECGs and normal VCGs. It is concluded that analysis of high gain VCG P loops provides a 30% higher yield for the diagnosis of echocardiographically determined left atrial enlargement when compared with P wave examination on the standard ECG.  相似文献   

20.
The ability of ECG-VCG to predict the severity of postinfarction LV asynergy was evaluated in 152 patients with previous myocardial infarction who underwent left cineventriculography in the right anterior oblique view. Various ECG and VCG signs were examined in order to predict the existence of severe asynergy in general (dyskinesia or akinesia or severe hypokinesia) and of dyskinesia in particular. In patients with inferior myocardial infarction (Group A) persistent ST segment elevation was the only specific ECG sign (100%) of severe asynergy; it had a poor sensitivity (6.2%). Four frontal VCG signs (presence of terminal bite, y- greater than 0.18 mV, maximum early superior vector along x axis = MESV greater than or equal to 1.3 mV, duration of initial superior forces = DISF greater than 50 msec) increased the sensitivity of the ECG-VCG method to 75.8% while maintaining a 100% specificity. Regarding the diagnosis of dyskinesia, only the ECG sign of persistent ST segment elevation and the VCG sign of y- greater than or equal to 0.3 mV had a 100% specificity. The sensitivity of the ECG-VCG method was 33.3% (16.6% ECG and 16.6% VCG). In patients with anterior myocardial infarction (Group B), concerning the diagnosis of severe asynergy, the ECG signs of sigma ST greater than 3 mm in anterior leads; pathologic Q wave in four or more anterior leads (including D1 and aVL); and the presence of LAH or LAH + RBBB, had a 100% specificity and a good sensitivity (60.5%). The VCG sign of a narrow horizontal QRS loop increased the sensitivity of the ECG-VCG method to 71% while maintaining a 100% specificity. As for the diagnosis of dyskinesia, the ECG signs with a 100% specificity were sigma ST greater than or equal to 5 mm in anterior leads, a pathologic Q wave in more than five anterior leads (including I and a VL) and RBBB + LAH; these variables had a sensitivity of 48.3%. The VCG sign of a narrow horizontal QRS loop increased the sensitivity of the ECG-VCG method to 79.3% while maintaining a 100% specificity. In patients with inferior plus anterior myocardial infarction (Group A + B) the signs mentioned above for each group were evaluated, confirming a 100% specificity. Regarding the diagnosis of severe asynergy, the ECG signs had a sensitivity of 61.3%, while VCG increased the sensitivity of the ECG-VCG method to 90.3%.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   

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