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41.
Takashi Oki Nobuo Fukuda Arata Iuchi Tomotsugu Tabata Hirotsugu Yamada Kazuyo Fukuda Kazuyo Manabe Susumu Ito 《Clinical cardiology》1996,19(8):639-643
Hypothesis: This study was undertaken to clarify the mechanisms of mitral regurgitation (MR) in dilated hearts. Methods: in all, 68 patients with dilated heart and MR, including 26 patients with dilated cardiomyopathy (DCM), 24 with prior anterior myocardial infarction (A-MI), and 18 with prior posteroinferior myocardial infarction (I-MI), as well as 25 normal subjects were examined by transesophageal two-dimensional and color Doppler echocardiography. Results: The maximum area of the MR signal in the DCM group correlated positively with the anteroposterior diameter of the mitral annulus at late systole. Although the coaptation edge length of the anterior and posterior mitral leaflets appeared shorter in dilated hearts than in the hearts of controls, a significant difference did not exist. The length of the coaptation edge correlated negatively with the maximum area of the MR signal in all dilated hearts, and characteristic systolic displacement of the coaptation point of both mitral leaflets occurred. The MI groups demonstrated anterior and posterior displacement in the direction of the short axis of the left ventricle in the A-MI and I-MI groups, respectively. However, the DCM group demonstrated inferior displacement toward the long axis of the left ventricle; its magnitude correlated positively with the maximum area of the MR signal. Conclusion: A major cause of MR in dilated hearts is mitral malcoaptation due to displacement of the coaptation point of the mitral leaflets along the long or short axis of the left ventricle. This is caused by left ventricular enlargement and/or asynergy of the left ventricular wall, rather than by a decrease in mitral coaptation edge length due to mitral annular dilation. 相似文献
42.
Kim SR Imoto S Ikawa H Ando K Mita K Shimizu K Taniguchi M Sasase N Matsuoka T Kudo M Kawada N Hayashi Y 《Internal medicine (Tokyo, Japan)》2008,47(21):1899-1903
A case of 22 mm hypervascular nodule in segment two of the liver but without hepatitis B or C virus infection in a 32-year-old Japanese woman with a history of alcohol abuse is presented. Imaging studies such as contrast-enhanced ultrasound, computed tomography and magnetic resonance imaging showed hypervascularity in the early phase and venous washout in the late phase. Histologically, stellate scar-like fibrous septa, pericellular fibrosis, fatty change, neutrophilic infiltration, slight increase of cell density, and diffuse capillarization of the sinusoids together with small unpaired arteries were observed. The nodule was diagnosed as focal nodular hyperplasia-like lesion in alcoholic liver cirrhosis. 相似文献
43.
Oki T Fukuda N Iuchi A Tabata T Manabe K Kageji Y Sasaki M Yamada H Ito S 《Echocardiography (Mount Kisco, N.Y.)》1996,13(6):623-626
A patient of cardiac amyloidosis was found to have mid-to late diastolic retrograde flow from the left atrium (LA) to the pulmonary vein. Congo-red staining was positive for amyloid in the rectal tissue. M-mode and two-dimensional echocardiograms revealed symmetric hypertrophy and typical speckled pattern of the left ventricle (LV). The LV pressure curve showed a dip and plateau configuration during diastole, and end-diastolic pressure was 28 mmHg. In addition, the LV pressure was high at mid-diastole, surpassing the pulmonary capillary wedge pressure from mid-to late diastole. The transmitral flow velocity revealed "restrictive" pattern, and the pulmonary venous flow velocity showed retrograde flow from the LA to the pulmonary vein during mid-diastole and atrial systole. It is suggested that recording of the pulmonary venous flow velocity by transesophageal pulsed Doppler echocardiography is useful for understanding the mechanism of the development of pulmonary congestion or edema. 相似文献
44.
Junya Fukuoka Masaki Tominaga Kazuya Ichikado Tomonori Tanaka Hidenori Ichiyasu Hirotsugu Kohrogi Shin Ishizawa Moritaka Suga 《Pathology international》2013,63(2):108-112
Human T‐cell leukemia virus type 1 (HTLV‐1) carriers are rarely subject to inflammatory disorders in multiple organs, other than the well‐known complication, adult T‐cell leukemia/lymphoma (ATLL). HTLV‐1 associated bronchiolo‐alveolar disorder (HABA) has been proposed as an immune mediated pulmonary reaction seen rarely in HTLV‐1 carriers. The reported clinico‐pathological patterns of HABA are diffuse panbronchiolitis (DPB) and lymphoid interstitial pneumonia (LIP). We here report three cases of HTLV‐1 carriers showing miliary micro‐nodules throughout both lungs. Microscopic examination in the video assisted thoracic surgery biopsies demonstrated that all cases had multiple discrete micro‐nodules which consisted of marked lymphoid infiltration, granulomas, eosinophils and a few foci of necrosis inside the granuloma. No findings indicating ATLL, other neoplastic conditions, infection or interstitial pneumonia, including DPB and LIP, were present following panels of special staining and immunohistochemical examinations. Two patients improved without treatment within one month, with no evidence of recurrence after 7 years. One patient showed slow deterioration of lung reticular shadows in spite of a low dose corticosteroid therapy (prednisolone 10 mg/day). We believe these cases may be a newly recognized variant of HABA. 相似文献
45.
Evaluation of femoral perfusion in a rabbit model of steroid‐induced osteonecrosis by dynamic contrast‐enhanced mri with a high magnetic field MRI system 下载免费PDF全文
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48.
Masaki Ohsawa Akira Okayama Tomonori Okamura Kazuyoshi Itai Motoyuki Nakamura Kozo Tanno Karen Kato Yumi Yaegashi Toshiyuki Onoda Kiyomi Sakata Hirotsugu Ueshima 《Circulation journal》2007,71(6):814-819
BACKGROUND: The extent to which atrial fibrillation (AF) contributes to mortality in the Japanese general population has not been clarified. METHODS AND RESULTS: A randomly sampled general population from all over Japan (4,154 men, 5,329 women; age > or =30 years) was enrolled. Single electrocardiogram recordings were taken in the baseline survey. Stroke death, cardiovascular deaths and all-cause deaths during the subsequent 19 years were analyzed by the presence of AF at baseline. Cox's regression analysis was carried out to estimate the hazard ratios (HRs) of each cause of death attributable to AF after adjusting for other risk factors. Prevalence of AF was 0.64% in the study. The observed person-years were 162,980 among persons without AF and 699 among persons with AF. There were 1,919 deaths. Multivariate adjusted HRs for stroke death, cardiovascular death and all-cause death were 2.69, 2.76 and 1.88, respectively (p<0.05). These HRs were 14.7, 9.63 and 4.00 among persons aged 64 years or younger (p<0.05). CONCLUSION: AF affects stroke mortality, cardiovascular mortality and all-cause mortality in the Japanese general population. Careful attention should be paid to persons with AF in order to prevent future cardiovascular events. 相似文献
49.
Oki T Iuchi A Tabata T Yamada H Manabe K Fukuda K Abe M Fukuda N Ito S 《Echocardiography (Mount Kisco, N.Y.)》1998,15(1):43-50
We recorded transmitral and pulmonary venous flow velocities using transthoracic continuous-wave and transesophageal pulsed Doppler echocardiography, respectively, in 36 patients with mitral stenosis who were in sinus rhythm to investigate the left atrial contribution to left ventricular filling in mitral stenosis. The mitral valve area was determined by transthoracic two-dimensional short-axis echocardiography. Patients were classified as having mild stenosis (± 1.5 cm2 , n = 17) or moderate stenosis (< 1.5 cm2 , n = 19). The mean pulmonary capillary wedge pressure and left atrial maximal diameter were significantly larger, and left atrial volume change during atrial contraction was significantly smaller in the moderate group than in the mild group. The percent left atrial contribution to left ventricular filling, estimated from the transmitral flow velocity, the peak atrial systolic velocity, and the percent ratio of left atrial systolic regurgitation to left atrial filling, estimated from the pulmonary venous flow velocity, were significantly lower in the moderate group than in the mild group. The percent left atrial contribution to left ventricular filling, the peak atrial systolic velocity, and the percent ratio of left atrial systolic regurgitation to left atrial filling were positively correlated with the mitral valve area and negatively correlated with the mean pulmonary capillary wedge pressure. These results suggest that the left atrial contribution to left ventricular filling in patients with mitral stenosis in sinus rhythm decreases as the severity of valve stenosis increases, and that analysis of the atrial systolic waves of the transmitral and pulmonary venous flow velocities provides important information for evaluation of left atrial systolic performance in patients with mitral stenosis. 相似文献
50.
Emi Sasagawa Hirotsugu Aiga Edith Yanira Corado Soriano Blanca Leticia Cuyuch Marroquín Marta Alicia Hernández Ramírez Ana Vilma Guevara de Aguilar José Eduardo Romero Chévez Hector Manuel Ramos Hernández Rafael Antonio Cedillos Chizuru Misago Kiyoshi Kita 《The American journal of tropical medicine and hygiene》2015,93(2):326-333
To estimate the incidence (any mother to child) and rate (from seropositive mother to child) of mother-to-child transmission of Trypanosoma cruzi, a serological census was conducted, targeting pregnant women and infants born to seropositive mothers, in four municipalities of El Salvador. Of 943 pregnant women, 36 (3.8%) were seropositive for T. cruzi. Of 36, 32 proceeded to serological tests of their infants when they became 6–8 months of age. Six infants seropositive at the age of 6–8 months further proceeded to second-stage serological test at the age of 9–16 months. As the result, one infant was congenitally infected. Thus, serological tests at the age of 6–8 months produced five false positives. To ensure earlier effective medication only for true positives, identification of seropositive infants at the age of 9–16 months is crucial. Incidence and rate of mother-to-child transmission were 0.14 (per 100 person-years) and 4.0%, respectively. Estimated number of children infected through mother-to-child transmission in El Salvador (170 per year) was much higher than that of human immunodeficiency virus (HIV; seven per year). It is recommended that serological testing for T. cruzi be integrated into those for HIV and syphilis as part of antenatal care package. 相似文献