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1.
Shiro Akinaga Tadashi Ashizawa Katsushige Gomi Hiroe Ohno Makoto Morimoto Chikara Murakata Masami Okabe 《Cancer chemotherapy and pharmacology》1992,29(4):266-272
Summary Novel derivatives of K-252a, (8R*,9S*,11S*)-(–)-9-hydroxy-9-methoxycarbonyl-8-methyl-2,3,9,10-tetrahydro-8, 11-epoxy-1H,8H,11H-2,7b,11a-triazadibenzo [a,g]-cycloocta[cde]trinden-1-one, an inhibitor of protein kinases and calmodulin-dependent phosphodiesterase, were synthesized and evaluated for their antitumor activity in vitro and in vivo. Of ten derivatives tested, four were active against the P388 murine leukemia i. p.-i. p. system, although K-252a was inactive. Among these derivatives, KT6124 was selected for further biological evaluation studies because its efficacy was the highest. KT6124 was also active against sarcoma 180 and B16 melanoma. It exerted a relatively broad spectrum of antiproliferative activity against 20 human tumor cell lines in vitro. To determine the mechanism(s) of action underlying the antitumor activity of KT6124, we tested the drug for inhibition of protein kinases, including Ca2+-and phospholipid-dependent protein kinase (PKC), in intact A431 human epidermoid carcinoma cells in comparison with the PKC-inhibitory activity of K-252a. KT6124 did not antagonize the action of phorbol 12-myristate 13-acetate (PMA) in A431 cells, whereas K-252a did, suggesting that KT6124 may not act on protein kinases in the cells. The interaction of KT6124 with DNA in living cells was examined by the alkaline elution method. KT6124 apparantly exhibited DNA scission both dose-and time-dependently in the target cells. The DNA breakage was dependent on proteinase K treatment, suggesting its possible interaction with DNA-related enzyme(s). These results indicate that KT6124 exerts antitumor activity by acting on DNA or on DNA-related enzyme(s) in tumor cells rather than via the inhibition of protein kinases. 相似文献
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3.
Shuichi Sato Fumiko Nasu Katsutoshi Motegi 《Journal of oral and maxillofacial surgery》2002,60(8):867-872
PURPOSE: The purpose of this study was to examine changes of chewing movement and masticatory efficiency during the natural course of nonreducing disc displacement of the temporomandibular joint (TMJ). PATIENTS AND METHODS: The subjects were 15 patients who had been diagnosed with nonreducing disc displacement of the TMJ but had received no treatment. Chewing movement and masticatory efficiency were examined at the initial visit and at a mean follow-up of 21.7 months, using mandibular kinesiography and adenosine triphosphate ebteric-coated granules. As a control, 23 persons who had no current or previous TMJ symptoms were studied. RESULTS: The patients' clinical signs and symptoms tended to be alleviated during the follow-up period. In normal controls, chewing movement showed lateral excursion to the chewing side on both the right and left sides. In patients, chewing movement at the initial visit showed lateral excursion to the chewing side during chewing on the TMJ affected side, but no such deviation was noted during chewing on the TMJ unaffected side in the horizontal plane. However, chewing movement at follow-up became similar to that of controls. In patients, masticatory efficiency became better during the natural course, although that at follow-up did not always reach the control's level. CONCLUSION: In untreated patients with nonreducing disc displacement of the TMJ, chewing movement and masticatory efficiency tend to improve spontaneously. 相似文献
4.
Pure motor hemiplegia (PMH) is, in most cases, caused by a lacunar infarction. However, pure motor monoparesis (PMM), i.e., isolated motor involvement with spasticity in one limb, has drawn little attention. We studied prospectively 5 patients with PMM and found that it was always due to a mass lesion in the contralateral superficial cerebral hemisphere. Our observation suggests that PMM should not be regarded as simply a variant of PMH. 相似文献
5.
Toyohiro Kagawa Fumiko Fukunari Tomoko Shiraishi Miwako Yamasaki Takahiro Ichihara Yuka Kihara Ryousuke Zeze Kentaro Nogami Kenji Yuasa 《Oral Radiology》2006,22(2):47-51
Objectives To develop a simple image viewer that utilizes image files in general-purpose formats that are written from the original 3DX
volume data.
Methods We used FLASH MX2004 for Macintosh to develop a simple image viewer. In developing the software for the simple image viewer,
we decided that the viewer should provide the following features: (1) be available to both Windows OS and Mac OS, (2) allow
interlocking of the 3D images, (3) display image enlargement, and (4) allow distance measurements. The accuracy of the distance
measurements was evaluated.
Results The procedure was as follows: (1) write 3D images in jpeg format to a folder on i-VIEW; (2) place the folder containing the
3D images into the directory of the simple image viewer software on a PC; (3) start the software and open the window to input
the folder name containing the 3D images; and (4) display the 3D images. Our viewer had features such as image enlargement,
interlocking 3D images, drawing, and distance measurements. No significant differences were shown between the measurements
made by our simple viewer and the actual values of the images in any direction.
Conclusions Our image-viewing software for 3DX is beneficial for clinical use. 相似文献
6.
Toshiya Inada M.D. Fumiko Minagawa B.A. Satoru Iwashita M.D. Tatsuji Tokui M.D. 《Psychiatry and clinical neurosciences》1994,48(4):729-735
Abstract: In order to examine the characteristics of potential difficult-to-manage psychiatric cases, seven potential subgroups were extracted from the criminal offenders who were sent to the division of psychiatric diagnosis, Tokyo District Public Prosecutors Office for Pre-Prosecution Psychiatric Justice (PPPJ). The following criteria were used to select the potential subgroups: offenders who had experienced compulsory discharge from a mental hospital, those who had experienced Involuntary Admission to the mental hospital by the Prefectural Governor at least twice, those who had experienced admission to mental hospitals on more than 5 occasions, those who had been put on PPPJ previously for other criminal matters at least 3 times, those who had previously attempted suicide, and those who had committed homicide or arson. From the results of this study, it could be concluded that at least two types of "difficult-to-manage" psychiatric cases exist in the criminal offenders. 相似文献
7.
Observation on the effects of Chinese medicine zhenxuanyin for improving cerebral blood flow in rats with cerebral ischemia. 总被引:1,自引:0,他引:1
W Jingyi M Yasuhiro H Naoya R C Seok Y Yoshiharu T Nagara T Fumiko M Shigeru K Junji 《中医杂志(英文版)》1997,17(4):299-303
Zhenxuanyin [symbol: see text] is composed of pure Chinese medicinal herbs, such as gastrodia tuber, poria cocos, ligusticum wallichii etc. 4-verssel occlusion (4VO) model rats were reperfused after 30 minutes' complete occlusion, and Zhenxuanyin was administered 3 times a day. 24 hours later, 123I-IMP uptake in the brain was evaluated as an index of cerebral blood flow (CBF). The results show that Zhenxuanyin (0.03 g/kg, 0.3 g/kg, 1 g/kg, or 3 g/kg a day) can greatly improve the blood flow in the main cerebral regions, and 0.3 g/kg can increase cerebral blood flow (CBF) to the normal level. 相似文献
8.
K Ashizawa K Uchikawa T Hattori Y Ishibashi T Sato Y Miyake 《Journal of pharmaceutical sciences》1989,78(11):893-899
(6R,7R)-7-[2-(5-Amino-1,2,4-thiadiazol-3-yl)-(Z)-2-methoxy- iminoacetamid]-3- [(4-carbamoyl-1-quinuclidinio)methyl]-8-oxo-5-thia-1-azabicyclo [4,2,0]oct-2-ene-2-carboxylate (1; E1040) was isolated as alpha-(decahydrate), beta-(pentahydrate), and gamma-form (anhydrate) crystals and the X-ray amorphous form. The relationship between the pseudopolymorphic crystal forms of this compound and water content was studied by X-ray diffractometry, coulometric moisture analysis, thermal analysis, and hygroscopic and vacuum-freeze-drying experiments. The phase transition of crystalline 1 clearly indicated the effect of water content on dehydration. During dehydration, hydrated alpha-form (decahydrate) crystals and beta-form (pentahydrate) crystals became anhydrate gamma-form crystals, with the diffraction angle shifting toward shorter spacing accompanied by line broadening. These results indicate conversion of hydrate 1 crystals to the anhydrous form and contraction of the crystal lattice. It was estimated that the decahydrate (alpha-form) crystals contain 8 mol/mol crystal water and 2 mol/mol adhesion water, and that the pentahydrate (beta-form) crystals contain 4 mol/mol crystal water and 1 mol/mol adhesion water. These estimates were made by comparing the data from equilibrium hydration experiments and vacuum-freeze-drying experiments. It thus follows that gamma-form crystals are anhydrate and the X-ray amorphous form exists in either the hydrous or anhydrous form. 相似文献
9.
10.
Shuichi Matsumura Sawako Ii Haruo Shigeno Toshiyuki Tanaka Fumiko Okuda Yukimasa Shimura Kazunobu Toshima 《Macromolecular chemistry and physics.》1993,194(12):3237-3246
As a design for a biodegradable functional polymer, compositionally homogeneous poly[(sodium acrylate)-co-(vinyl alcohol)] [P(SA-co-VA)], containing varying amounts of vinyl alcohol groups as biodegradable segments were prepared and their biodegradability and builder performance in detergent formulations were analyzed with respect to the successive vinyl alcohol length. It was found that the acrylate copolymers having more than 80 mol-% vinyl alcohol content showed biodegradability. That is, P(SA-co-VA) having a vinyl alcohol chain length of more than about 5–6 is cleaved by PVA-degrading microbes. This indicates that the vinyl alcohol blocks, which act as biodegradable segments, should be incorporated into the polymer chain in such a manner that they are accepted as substrates by the PVA-degrading enzymes. 相似文献