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21.
Yoshimasa Matsuda Shinya Ono Yosuke Otake Shinya Handa Katsumi Kose Tomoyuki Haishi Shigeto Yamada Chikako Uwabe Kohei Shiota 《Magnetic resonance in medical sciences》2007,6(3):139-146
Using 4 and 8-channel super-parallel magnetic resonance (MR) microscopes with a horizontal bore 2.34T superconducting magnet developed for 3-dimensional MR microscopy of the large Kyoto Collection of Human Embryos, we acquired T(1)-weighted 3D images of 1204 embryos at a spatial resolution of (40 microm)(3) to (150 microm)(3) in about 2 years. Similarity of image contrast between the T(1)-weighted images and stained anatomical sections indicated that T(1)-weighted 3D images could be used for an anatomical 3D image database for human embryology. 相似文献
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The energy metabolism of the brain was measured in three types of ischemic models in the cat using phosphorus-31 magnetic resonance spectroscopy. The cerebral ischemia was produced as follows. In Group 1, two balloons were inflated in the left subclavian artery and the brachiocephalic trunk. In Group 2, the left middle cerebral artery was occluded through a transorbital approach. A combination of the two was employed in Group 3. Phosphorus-31 magnetic resonance spectra were obtained serially during 2 hours of ischemia. Immediately after occlusion, peaks of phosphocreatine and adenosine triphosphate decreased, whereas the peak of inorganic phosphate increased and split in two. Intracellular pH determined by chemical shift of the inorganic phosphate peak decreased. These changes were more pronounced in Group 3 when compared with the other groups. Histological study showed no infarction in Group 1 and infarcted areas in Groups 2 and 3. The size of the infarcted area in Group 3 was larger than that in Group 2. These results suggest that the model of middle cerebral artery occlusion potentiated with the occlusion of the brachiocephalic trunk and the left subclavian artery by balloon catheters is a reliable stroke model and that phosphorus-31 magnetic resonance spectroscopy is useful to understand the pathophysiological state of cerebral ischemia in vivo. 相似文献
24.
Kazunari Yamaguchi Tsukasa Inaoka Ryutaro Ohtsuka Tomoya Akimichi Tetsuro Hongo Toshio Kawabe Minato Nakazawa Makoto Futatsuka Kiyoshi Takatsuki 《Cancer science》1993,84(7):715-719
Seven hundred and twenty-three serum samples from individuals in 13 Gidra-speaking villages in Western Province, Papua New Guinea were tested for evidence of infection with human T- lymphotropic virus type I (HTLV-I), human immunodeficiency virus type I (HIV-I), hepatitis B virus (HBV) and hepatitis C virus (HCV). No samples were positive for antibodies to HIV-I. Antibodies to HTLV-I were found in 13 samples (1.8%), HBV surface antigens (HBsAg) were found in 86 samples (11.9%), and antibodies to HCV were found in 30 samples (4.1%). Six (46.2%) of 13 HTLV-I positive samples were positive for HCV or HBsAg. The seropositive rate varied in different villages and the incidence of HTLV-I and HCV was higher in coastal and riverine areas than inland. 相似文献
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Four cases of trigeminal schwannoma with different clinical presentations are reported. Two patients had root-type tumors and two ganglion-type tumors. Computed tomography demonstrated the mass in each case, but extension of the tumor into Meckel's cave, displaced but uninvolved seventh and eighth cranial nerves, extension of the tumor into the orbit or into the infratemporal fossa, and other anatomical details were far more clearly shown by magnetic resonance imaging, which provided confirmation of the mass lesions in the base of the brain and within the posterior fossa. 相似文献
27.
W Sakamoto K Fujie H Handa T Ogihara M Mino 《International journal for vitamin and nutrition research. Internationale Zeitschrift für Vitamin- und Ern?hrungsforschung. Journal international de vitaminologie et de nutrition》1990,60(4):338-342
Rat peritoneal macrophages, which were induced by intraperitoneal injection of vitamin E for 6 successive days, contained 387.6 to 569.0 ng alpha-tocopherol/10(6) cells and produced 0.9 to 1.5 nmol O2-/min/10(6) cells following stimulation by phorbol myristate acetate (PMA). On the other hand, control macrophages contained 1.7 ng alpha-tocopherol/10(6) cells and produced 3.9 to 4.5 nmol O2-/min/10(6) cells. The particulate fraction of macrophages from vitamin E-treated rats contained 285.2 to 294.4 ng alpha-tocopherol/10(6) cells and showed scarcely any protein kinase C activity, whereas the specific activity of control rats showed 323 to 357 pmol/min/mg protein. From these results, we concluded that vitamin E seems to decrease O2- production from macrophages stimulated with PMA through inhibition of protein kinase C. 相似文献
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S. Nakasu Y. Nakasu M. Nakajima M. Yokoyama M. Matsuda J. Handa 《Acta neurochirurgica》1996,138(6):763-770
Summary Cell kinetic study plays an important role in treatment planning of brain tumour patients. MIB-1 antibody has recently become available, which detects Ki-67 antigen even in the formalin-fixed paraffin-embedded specimens. We performed MIB-1 immunostaining in 50 meningiomas and 50 neurinomas, and estimated the cell cycle time (tc) and potential doubling time (Tpot) from MIB-1 staining index (MIB-1 SI) and mitotic index (MI). MIB-1 SI logarithmically correlated with MI in both meningiomas and neurinomas. The tc and the Tpot were expressed as a function of the mitosis time (tm), while the tm is known to be around one hour and not exceeding two hours. When the tm was assumed to be one hour, the average tcs of meningiomas and neurinomas were 6.53±3.56 days and 7.67±3.27 days, respectively. The Tpots were447 × (MIB-1 SI)–1.29 × tm in meningiomas, and490 × (MIB-1 SI)
–0.98
× tm in neurinomas.The tumour doubling times (Tds) were calculated from serial imaging studies in 22 neurinomas and 15 meningiomas. The Tds were formulated as794 × (MIB-1 SI)
–0.83 in meningiomas and1380 × (MIB-1 SI)
–0.97 in neurinomas. Most of the Tds correlated well with the Tpots in meningiomas and neurinomas, and exceeded values of the Tpot when the tm is assumed to be one hour, although a few tumours showed unexpectedly longer Tds. The Tpot and the tc estimated from MIB-1 SI and MI are clinically useful parameters for predicting the growth potential of meningiomas and neurinomas where no other simple methods are available. 相似文献