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31.
Fuyumi Yamamoto Hiroshi Kasai Tadayoshi Bessho Myung-Hee Chung Hideo Inoue Eiko Ohtsuka Tomokatsu Hori Susumu Nishimura 《Cancer science》1992,83(4):351-357
Here we report the finding of enzymatic activity that specifically cleaves DNA containing 8-hydroxyguanine (oh8 Gua) residues in various mammalian cells. To detect this activity, we used a synthetic double-stranded DNA containing a single oh8 Gua at a defined position as the substrate, and analyzed the products of enzymatic digestion by polyacrylamide gel electrophoresis. Two cleavage sites near the oh8 Gua residue were detected with partially purified fractions from cow brain and rat liver, and also with preparations from all mammalian tissues examined. These results suggest that enzymatic activity for the removal of oh8 Gua from DNA is widely distributed in mammalian cells. 相似文献
32.
Shiro Nakaike Takehiro Yamagishi Kayoko Nanaumi Susumu Otomo Shigeru Tsukagoshi 《Cancer science》1992,83(4):402-409
A novel antitumor compound, N-β-dimethylaminoethyl 9-carboxy-5-hydroxy-10-methoxybenzo[a]-phenazine-6-carboxamide sodium salt (NC-190), was evaluated for antitumor activity in vitro against cultured tumor cell lines, and the kinetics of cell killing was elucidated. NC-190 strongly inhibited the growth of all of 3 murine tumor cell lines, 7 human tumor cell lines and 2 normal cell lines. With continuous exposure, the 50% inhibition concentrations were in the range of 0.005–0.06 μg/ml, except for KATO-III (2.15 μ g/ml). By colony-forming assay, concentrations of NC-190 giving 90% cell kill (IC90 ) at various exposure times were obtained with HeLa S3 cells. The plot of IC90 exposure time on a log-log scale was linear for NC-190 with a slope of -1, which is typical for cell cycle phase-nonspecific agents. A 2 h treatment with NC-190 induced a rapid reduction in cell viability at doses of more than 3 μ g/ml. At the dose where colony formation was completely inhibited, cell viability was persistently reduced to below 20% during the cell culture period. NC-190 cauced a dose- and time-dependent reduction in DNA synthesis. The inhibitions of RNA and protein synthesis were less than that of DNA synthesis. Spectroscopic studies of NC-190 mixed with calf thymus DNA demonstrated that NC-190 was capable of interacting with DNA. However, DNA thermal denaturation studies suggested that intercalation of NC-190 was weak in comparison with those of classical intercalating drugs. 相似文献
33.
Toshiharu Yamagishi Susumu Ishikawa Ichiro Yoshida Akio Ohtaki Toru Takahashi Satoshi Ohki Shuji Sakata Yasuo Morishita 《Surgery today》1997,27(9):874-875
We describe our technique for performing direct thoracoscopic closure of a congenital partial pericardial defect, which was
successfully employed in a 15-year-old boy. This is the first such report of a procedure that is noninvasive and may therefore
become the treatment of choice for patients with a small congenital pericardial defect. 相似文献
34.
Y Katayama T Umekawa Y Ishikawa M Kodama M Takada Y Katoh K Kataoka K Kohri M Iguchi T Kurita 《Nihon Hinyōkika Gakkai zasshi. The japanese journal of urology》1990,81(1):89-95
Bone mineral contents of calcium urolithiasis patients (105 males and 52 females) were measured by the microdensitometry (MD) method, and the patients were divided into the MD normal group and the MD abnormal group. The patients were also divided into the group (21 males and 3 females) treated with thiazides for 1 year or more and the nontreated group to examine various factors in blood and urine. [Nontreated group] The rate of MD abnormality was higher in younger males. The rate tended to increase with age in females. Alkaline phosphatase values were significantly higher in MD abnormal group males than in MD normal group males. Urinary calcium excretion and PTH values were significantly higher in MD abnormal group females than in MD normal group females. Comparison of hypercalciuria and normocalciuria revealed no significant difference between the MD normal rate and the MD abnormal rate. Comparison of single of stone formers and recurrent stone formers also revealed no significant difference between the MD normal rate and the MD abnormal rate. [Treated group] PTH and alkaline phosphatase values were significantly higher in the treated group than in the nontreated group. Alkaline phosphatase values were significantly higher in the MD abnormal group. From the viewpoint of stone recurrence prevention, the monitoring of bones where the majority of calcium in the body is present is considered important besides behavior of calcium in blood and urine. 相似文献
35.
Nine patients with small hepatocellular carcinomas, ranging up to 2 cm in size (phi: 1.7 +/- 0.2 cm, mean +/- SD), have been encountered, and in two of these patients the cancer was not identifiable by intraoperative ultrasonography. Thus to achieve a better detection of such small hepatic cancers, enhanced intraoperative ultrasonography was tested. Detection by enhanced intraoperative ultrasonography proved successful in all cases. These preliminary results indicate the potential of carbon dioxide as a contrast agent to enhance intraoperative visualization of small liver cancers. 相似文献
36.
Pyomyositis is a bacterial infection with abscess formation affecting large skeletal muscles. It is predominantly caused by Staphylococcus aureus. The disease is common in tropical areas, but rare in temperate climates. We report a patient with multiple myeloma who developed a giant elastic tumor on the right thigh and a hen egg-sized tumor on the right upper arm. MR imaging revealed cystic spaces in the femoral quadriceps and brachial biceps muscles. A large amount of pus with foul smell was removed by incision, drainage and aspiration of the two tumors. The lesions were successfully treated with intravenous administration of antibiotics. Repeated bacterial cultures yielded only Bacteroids fragilis. To our knowledge, this is the first report of pyomyositis due to Bacteroides fragilis. 相似文献
37.
A 62-year-old woman with diabetic triopathy developed widespread erythematous macules, numerous pustules, and a high fever after she underwent electric coagulation for vitreous hemorrhage. She was administered several drugs at that time. After discontinuation of the drugs, the eruption disappeared, and the fever returned to normal within two weeks. A positive patch test with isepamicin sulfate highly suggested that the symptoms described above were due to drug allergy. Cadralazine, which was positive in the drug lymphocyte stimulation test (DLST), could not be excluded from the causative drugs. A false-positive DLST with ofloxacin was confirmed by an accidental challenge test. To our knowledge, this is the first report of acute generalized exanthematous pustulosis due to isepamicin sulfate and/or cadralazine. 相似文献
38.
We studied choline acetyltransferase (CAT) activity in a rat model of brachial plexus injury. In experiment 1, we found that the CAT activity was remarkably high in the anterior roots and low in the posterior roots. In experiment 2, nerve root segments were extracted and examined for CAT activity in the root avulsion group (group A) and the plexus severance group (group B). CAT activity decreased day by day in group A, reaching about 1/20 of the normal 5 days postoperatively. By contrast, in group B activity decreased only slightly, and even at 90 days postoperatively was about 6,000 cpm (one-half normal level). As a result, CAT activity enabled us to distinghish postganglionic from preganglionic injury of the cervical roots. Furthermore, it was a useful adjunct for minimizing nerve loss in intercostal nerve transfer, distinguishing motor and sensory branches of the intercostal nerve, and evaluating the motor nerve activity. © 1995 Wiley-Liss, Inc. 相似文献
39.
K. Kohri T. Umekawa Y. Ishikawa Y. Katayama M. Kodama M. Takada Y. Katoh K. Kataoka M. Iguchi T. Kurita 《International urology and nephrology》1990,22(1):13-23
Factors relating alterations in plasma and urine composition to recurrence of urinary stones during drug therapy were investigated
by using a multiple regression analysis technique. These factors were influenced not only by the efficacy of the drugs but
also by other factors (plasma or urinary constituents and overall health of the patients, etc.). In order to study the effect
of drug therapy or other treatment on the alteration of plasma and urine constituents, multiple regression analysis is more
appropriate than Student's pairedt-test which has been used by some workers. These two analytical methods yield different results even if used on the same data. 相似文献
40.
Kazuhiro Sakata Akio Ohtaki Masaaki Aiba Susumu Ishikawa Yoshimi Otani Yasuo Morishita 《Surgery today》1997,27(1):88-89
We report herein the case of a 77-year-old man with a left ventricular tumor originating from the papillary muscle of the left ventricular wall, in whom a successful tumor resection with mitral valve replacement was performed. The pathological diagnosis of the tumor was confirmed as cardiac fibroma. His postoperative course was uneventful and he is currently well with no signs of recurrence 2 years after surgery. 相似文献