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Mitsuhiro Tozaki Kunihiko Fukuda Masafumi Suzuki 《Magnetic resonance in medical sciences》2006,5(3):137-146
PURPOSE: The purpose of this study was to assess the relationship between the amount of scirrhous component in invasive ductal carcinoma and its MR characteristics. MATERIALS AND METHODS: We retrospectively reviewed 71 consecutive patients with invasive ductal carcinoma smaller than 25 mm (average, 16.6 mm) in diameter. The scirrhous component was defined as invasive foci in small clusters of cancer cells showing desmoplasia. Invasive ductal carcinoma was subclassified into 3 groups in accordance with the amount of the scirrhous component (scirrhous component degree; SCD): SCD I (scirrhous component less than 20%), SCD II (intermediate), and SCD III (more than 80%). Dynamic magnetic resonance (MR) imaging was performed using volumetric interpolated sequence. Prior to dynamic study, T2*-weighted first-pass perfusion images were obtained before, during, and after bolus injection of 0.1 mmol Gd-DTPA/kg. RESULTS: Twenty-eight lesions were classified as SCD I, 14 as SCD II, and 29 as SCD III. Mass margin and signal intensity loss in the perfusion study were significantly different among the 3 SCD groups (P<0.001). The kinetic patterns were significantly different among the 3 SCD groups (P=0.04), and between SCD I/II and SCD III (P=0.03). The presence of enhancing internal septations was significantly different between SCD I/II and SCD III carcinomas (P=0.05). Central enhancement was only observed in SCD I carcinoma (4%; 3/71). CONCLUSION: The histological predominance of the scirrhous component in invasive ductal carcinoma may be one explanation for the differences in morphologic and kinetic patterns on MR imaging. 相似文献
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Kengo Maeda Shinji Kume Yoshihiko Nishio Shiro Maeda Yasuhiro Nishida Mikio Suzuki Takahiro Nakaguchi Toru Kawabata Osamu Hashimoto Takashi Hisanaga Atsunori Kashiwagi Hitoshi Yasuda 《Clinical neurology》2006,46(4):266-269
We report a 53-year-old woman with severe Graves' ophthalmopathy accompanied by uncontrolled myasthenia gravis. She presented remarkable exophthalmos, chemosis, and restriction of eye movement. Despite plasma exchange, steroid pulse therapy, local injection of steroid, and irradiation, ocular symptoms did not ameliorate. Since optic neuropathy was seen, orbital decompression surgery was performed in the left eye. Bilateral chemosis was improved after the surgery. Five years after surgery, there was no ocular palsy in the operated left eye, but in the contralateral eye. For the good prognosis of the eye movement, orbital decompression might be recommended in the severe Graves' ophthalmopathy accompanied by the optic neuropathy and/or ophthalmoplegia with proptosis. 相似文献
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Yasuyuki Suzuki Kazuyuki Daitoku Masahito Minakawa Kozo Fukui Ikuo Fukuda 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2006,54(1):44-46
We report the case of a 4-year-old girl who had quadricuspid aortic valve regurgitation with tetralogy of Fallot and pulmonary
atresia. This combination is very uncommon. Aortic valve replacement was performed successfully due to aortic regurgitation
which had progressed one year after the total repair. The dilated aortic annulus plus quadricuspid aortic valve may result
in progressive aortic regurgitation for a short period. 相似文献
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Hitoshi Ogino Nongchana Klangsuk Wu Jin Christopher T. Bowles Magdi H. Yacoub 《Artificial organs》1995,19(6):525-534
Abstract: The dependence of transient pressure characteristics of a ventricular assist device (VAD) on the compliance of its housing and cannulas was investigated in a mock circulation. The peak rate of change of pressure ( dP/dt max ) values was greater in the cannulas than other compartments and was associated with valve closure-induced pressure oscillations. When cannula compliance was increased from 0.0057 to 0.0129 cm3 /mm Hg, these values decreased by ˜20%, and outflow cannula pressure oscillation frequency decreased from 17.5 Hz by 35%. This trend was also apparent in the inflow. A VAD housing compliance increase from 0.0162 to 0.0483 cm3 /mm Hg caused a dP/dt max decrease of 30% in both the blood chamber and the outflow cannula. The effect of this change on the inflow was weaker implying that housing absorbs the energy associated with outflow deceleration more effectively than the inflow. These findings suggest that increasing VAD housing and cannulas compliance can improve hydrodynamic performance. 相似文献
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Experiments were performed on spinalized rats, transected at the Cl level. The intravenous administration of TRH and its analog YM-14673 (N alpha-[(S)-4-oxo-2-azetidinyl) carbonyl]-L-histidyl-L-prolinamide dehydrate) produced marked increases in the amplitude of mono- and polysynaptic reflex potentials and those of the withdrawal flexor reflexes. The effects of YM-14673 were stronger and longer-lasting than those of TRH. The stimulant action of TRH and YM-14673 on the flexor reflexes was not antagonized by prazosin, chlorpromazine, haloperidol or cyproheptadine, suggesting no involvement of the release of catecholamines or serotonin in the stimulant effects of TRH and its analog. Therefore, YM-14673 may be beneficial for the treatment of several spinal motor neuron diseases. 相似文献
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Nishida Koyo Mihara Kiyoshi Takino Toichi Nakane Sachi Takakura Yoshinobu Hashida Mitsuru Sezaki Hitoshi 《Pharmaceutical research》1991,8(4):437-444
The effect of electric charge on the hepatic disposition of macromolecules was studied in the rat. Charged derivatives of dextran (T-70) and bovine serum albumin (BSA), mitomycin C–dextran conjugates (MMC-D), and lactosaminated BSA (Lac-BSA) were employed as model macromolecules. After intravenous injection, cationic macromolecules were rapidly eliminated from plasma because of their extensive hepatic uptake, while anionic and neutral macromolecules were slowly eliminated. Cationic macromolecules were recovered from parenchymal and nonparenchymal hepatic cells at a cellular uptake (per unit cell number) ratio of 1.4–3.2, while that of Lac-BSA was 14. During liver perfusion using a single-pass constant infusion mode, cationic macromolecules were continuously extracted by the liver, with extraction ratios at steady-state (E
ss) ranging between 0.03 and 0.54, whereas anionic and neutral macromolecules were almost completely recovered in the outflow at steady state. The E
ss for cationized BSA (Cat-BSA) and cationic MMC-Dcat were concentration dependent and decreased at low temperatures and in the presence of colchicine and cytochalasin B. The possible participation of the internalization process in the uptake of cationic macromolecules by hepatocytes was suggested. 相似文献