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41.
Doppler ultrasound examination of prosthetic function and ventricular blood flow after mitral valve replacement 总被引:1,自引:0,他引:1
Two-dimensional color Doppler echocardiography enables delineation of the spatial and temporal distribution of blood flow in the heart. In this study, the method was applied for investigation of flow dynamics in multiple planes in the region of prosthetic mitral valves for comparison with that of native mitral valves. In 15 healthy subjects there was normal flow toward the transducer, coded in red, in the left ventricle along the posterolateral wall (left ventricular inflow region) and blue-coded flow away from the transducer in the left ventricular outflow region during diastole. In 40 patients with St. Jude mitral valve prosthesis and 17 with bioprosthesis the flow pattern in the left ventricle was reversed. Mitral inflow was directed against the interventricular septum, accordingly, into the left ventricular outflow region while the outflow pattern was displaced posterolaterally into the left ventricular inflow region during diastole. The angle between the aortic valve ring and the mitral annulus was significantly smaller than in the healthy subjects. The angle between the central axis of the mitral prosthesis and the mitral inflow, which was 0 degrees in healthy subjects, was increased by the medial deviation in particular, in those with mechanical St. Jude prostheses. The maximal transprosthetic velocity, measured in 70 patients, and the maximal pressure gradient calculated according to the Bernoulli equation was substantially greater than the values in healthy subjects. In contrast to findings associated with normally-functioning prostheses, in four patients with prosthetic malfunction there was a diastolic peak velocity of more than 2 m/s as well as marked turbulence in the inflow region. 相似文献
42.
Correlation of anatomic and hemodynamic features with aortic valve leaflet deformity in doubly committed subarterial ventricular septal defect 总被引:1,自引:0,他引:1
Kobayashi J Koike K Senzaki H Kobayashi T Tsunemoto M Ishizawa A Ohta Y Shimada M Omoto R 《Heart and vessels》1999,14(5):240-245
Summary The records of 153 patients with doubly committed subarterial ventricular septal defect (DCVSD) who underwent intracardiac repair were analyzed to evaluate factors responsible for aortic valve leaflet deformity. The patients were divided into two groups according to their echocardiographic and angiographic features as well as anatomic findings at operation: DCVSD without (17/153, 11.1%) and with arterial valve offsetting (136/153, 88.9%). Aortic regurgitation (AR) was much more prevalent in the patients with (50.0%) than in those without leaflet deformity (2.2%,P < 0.01). Arterial valve offsetting is one of the major contributing factors to the development of leaflet deformity, accounting for 5.9% in the patients without offsetting and 46.3% in those with offsetting (P < 0.01). Among the patients with arterial valve offsetting, the pulmonary-to-systemic pressure ratio was significantly higher (P < 0.01) in the patients without (0.76 ± 0.14) than in those with leaflet deformity (0.36 ± 0.12), suggesting that pulmonary hypertension might prevent the aortic valve leaflet from prolapsing in DCVSD. In addition, increased severity of aortic valve leaflet deformity and subsequent AR were observed with increasing age. These results suggest that aging and the presence of arterial valve offsetting as well as the absence of pulmonary hypertension might be factors responsible for aortic valve leaflet deformity and subsequent AR in DCVSD. The anatomic and hemodynamic features in DCVSD have a great impact on the development of aortic valve leaflet deformity and subsequent AR. 相似文献
43.
Ishikawa T Kobayashi Y Omoto A Adachi Y Nakagawa S Kaneko T Nishida K Miyamoto Y Chimori Y Yoshikawa T Kondo M 《Acta haematologica》1999,102(4):185-189
A 69-year-old Japanese female was admitted to our hospital due to a 2-month history of vomiting after eating. Examination of the small intestinal tract revealed a tumor with calcification in the inner portion, from the horizontal portion to the ascending portion of the duodenum, and jejunojejunostomy was performed. The pathological findings of the tumor gave a diagnosis of non-Hodgkin's lymphoma, diffuse small cleaved cell (Working Formulation classification), B cell type, of the jejunum. Calcification is rarely found in untreated malignant lymphoma and 15 cases of untreated malignant lymphoma with calcification have been reviewed. 相似文献
44.
Takeshi Imura Yuki Nagasawa Tetsuji Inagawa Naoki Imada Hiroaki Izumi Katsuya Emoto Itaru Tani Hiroyuki Yamasaki Yuichiro Ota Shuichi Oki Tadanori Maeda Osamu Araki 《Journal of Physical Therapy Science》2015,27(5):1383-1386
[Purpose] The efficacy of diffusion tensor imaging in the prediction of motor outcomes
and activities of daily living function remains unclear. We evaluated the most appropriate
diffusion tensor parameters and methodology to determine whether the region of interest-
or tractography-based method was more useful for predicting motor outcomes and activities
of daily living function in stroke patients. [Subjects and Methods] Diffusion tensor
imaging data within 10 days after stroke onset were collected and analyzed for 25
patients. The corticospinal tract was analyzed. Fractional anisotropy, number of fibers,
and apparent diffusion coefficient were used as diffusion tensor parameters. Motor
outcomes and activities of daily living function were evaluated on the same day as
diffusion tensor imaging and at 1 month post-onset. [Results] The fractional anisotropy
value of the affected corticospinal tract significantly correlated with the motor outcome
and activities of daily living function within 10 days post-onset and at 1 month
post-onset. Tthere were no significant correlations between other diffusion tensor
parameters and motor outcomes or activities of daily living function. [Conclusion] The
fractional anisotropy value of the affected corticospinal tract obtained using the
tractography-based method was useful for predicting motor outcomes and activities of daily
living function in stroke patients.Key words: Stroke, Diffusion tensor tractography, Activities of daily living function 相似文献
45.
46.
Feasibility of one‐step endoscopic metal stenting for distal malignant biliary obstruction 下载免费PDF全文
47.
48.
Itaru Yamamoto Eiji Matsuura Masahiro Horiba Kazuo Akima Kazuo Nomura Tetsushi Aizawa 《Journal of immunoassay & immunochemistry》2013,34(3):261-276
A sensitive double antibody and heterologous enzyme immunoassay for mabuterol was established. For competitive reactions, antibody raised against diazotized mabuterol-human serum albumin was incubated with a mixture of diazotized mabuterol analog (RC-1) labeled with β-D-galactosidase and standard or sample. Free and antibody-bound enzyme hapten were separated using anti-rabbit IgG immobilized on polystyrene balls. Activity of the enzyme on the solid phase was fluorometrically determined. The present immunoassay allows detection of 0.5 to 100 pg/tube of mabuterol. Pharmacokinetic behavior of this agent in human plasma and urine was studied after a single oral administration (50 yg). The maximum level was achieved after 2–3 hrs with approximately 280 pg mabuterol /ml of plasma and the half life of mabuterol was estimated to be 19.5 hrs. Cumulative amount of mabuterol in the first 72 hrs urine was 64.3 ± 13.2% of the administered dose. 相似文献
49.
50.
The aim of this study was to assess morphological differences between early-modern (Edo) Japanese and contemporary Japanese using recently uncovered human female remains at the Ikenohata-Shichikencho site in the Tokyo urban area. In this study, 30 female skeletal remains that still retained the upper and lower first molars and central incisors were selected [early-modern (Edo) Japanese group]. Forty contemporary female Japanese were selected as a control. Analyses by standard methods of geometric morphometrics revealed some morphological differences between the early-modern (Edo) Japanese group and the contemporary Japanese group. For example, the early-modern (Edo) Japanese group exhibited bimaxillary dentoalveolar protrusion, a flat occlusal plane, and a large S-N length. On the other hand, the contemporary Japanese group exhibited slight protrusion of the anterior nasal spine. These findings may be of interest to orthodontists who are studying age variation or temporal differences and could lead to a better understanding of morphological diversity and variability. 相似文献