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71.
M Kurihara S Shimauchi K Ohyama T Yamakawa H Watanabe S Hirakawa S Ohkuma 《Yakugaku zasshi : Journal of the Pharmaceutical Society of Japan》1990,110(10):783-787
One mol perchloric acid-soluble fraction (PASF) obtained from ascitic fluid of a patient (blood group B) with metastatic omentum tumor from ovarian cancer was a glycoprotein fraction containing 35.4% carbohydrate and exhibited A, B and Thomsen-Friedenreich (T) activities. This fraction was separated into three fractions, Frs. 1-3, by a gel filtration with Bio-Gel A-1.5 m column. Among these fractions, Fr. 1 which was obtained in a 5.5% yield to PASF, was a glycoprotein fraction with a high molecular weight, 23.3% carbohydrate and A, B and T activities. Other minor fraction, Fr. 2, and the major fraction, Fr. 3, contained 43.2% and 43.9% carbohydrate, but did not show A, B and T activities, respectively. 相似文献
72.
Structural determination of geometrical isomers of microcystins LR and RR from cyanobacteria by two-dimensional NMR spectroscopic techniques 总被引:6,自引:0,他引:6
K Harada K Ogawa K Matsuura H Murata M Suzuki M F Watanabe Y Itezono N Nakayama 《Chemical research in toxicology》1990,3(5):473-481
A nondestructive method using a combination of three 2D NMR techniques, DQF-COSY (double quantum filter correlation spectroscopy), HMQC (1H-detected multiple quantum coherence), and HMBC (heteronuclear multiple bond correlation), were developed for structural determination of microcystins, toxic heptapeptides produced by cyanobacteria. With this procedure we were able to assign all carbons and protons of microcystins LR (1) and RR (2), thus determining the constituent amino acid sequences. The procedure was also applied to the microcystin-associated nontoxic minor components, which have molecular weights and amino acid compositions similar to those of 1 and 2 and toxicities different from those of 1 and 2. From detailed analysis of these spectra we rapidly deduced that the minor components are geometrical isomers with respect to C-7 of the diene in Adda of the parent toxins. The structures were finally confirmed to be 3 and 4 by ROESY (rotating frame nuclear Overhauser and exchange spectroscopy) technique. 相似文献
73.
74.
J Shimizu Y Watanabe M Oda Y Hayashi T Iwa R Kamimura T Takashima 《Nihon Kyōbu Shikkan Gakkai zasshi》1991,29(10):1349-1353
A case of pulmonary varices in a 73-year-old female is presented. Routine chest X-ray revealed a mass in the right hilar region. CR tomogram showed a round, clearly defined mass at the right hilum. Computed tomography demonstrated marked enlargement of the proximal portion of the pulmonary vein at the entrance of the left atrium, which was suspected to be pulmonary varices. The diagnosis was confirmed by pulmonary angiography. During the arterial phase no abnormal findings were seen, but during the venous phase the veins of the right upper and middle lobes were found to be draining into the dilated pulmonary vein and then into the left atrium. Thus, the diagnosis of pulmonary varices was established. CT and angiography are the most useful methods for definitive diagnosis of pulmonary varices. 相似文献
75.
The in vitro antimicrobial activity of AO-128, an inhibitor of alpha-D-glucosidase, was evaluated against anaerobic bacteria of 45 reference strains (12 genera, 44 species). AO-128 inhibited no strains tested at a concentration of 1,600 micrograms/ml. The results strongly suggested that this compound would not have any influence on the human intestinal microflora, a majority of which is composed of anaerobic bacteria. 相似文献
76.
T Kubota H Yamaguchi M Watanabe T Yamamoto T Takahara T Takeuchi T Furukawa S Kase S Kodaira K Ishibiki 《Japanese journal of cancer research》1992,83(3):300-303
We implanted normal peripheral blood lymphocytes (PBL) from healthy donors and splenic tissues from patients with gastric cancers into the severe combined immunodeficient (SCID) mouse, demonstrating that SCID mouse with splenic tissue can produce a high level of human immunoglobulin G (IgG). The normal PBLs at 10(7) and 10(8)/mouse were implanted intraperitoneally, and three splenic tissues with a size of 3 x 3 x 3 mm from gastric cancer patients were inoculated subcutaneously into the bilateral backs of the mice. At 2, 4, 6 and 8 weeks after inoculation, mice were killed, and the human IgG was assessed by an ELISA method. SCID mice with splenic tissue revealed high human IgG levels from 2 weeks after inoculation and approximately 2 mg of IgG per ml was observed at 8 weeks post-implantation, while the IgG levels in mice treated with PBLs were limited. Since the half life of the extrinsic human IgG was 10.2 days, the high level of human IgG in the SCID mice was supposed to be produced by human plasma cells in the splenic tissue from gastric cancer patients. This model was thought to be adequate for evaluating human immunological functions in vivo. 相似文献
77.
M Tanaka E Takeuchi T Watanabe S Tamaki K Tajima T Maseki A Usui Y Hirate M Sawazaki T Abe 《[Zasshi] [Journal]. Nihon Kyōbu Geka Gakkai》1992,40(1):61-65
There is no definitive surgical procedure for acquired lesions of the tricuspid valve (TV). From Feb, 1978, through March, 1990, the surgical treatment for the organic lesions of TV was performed in 10 patients, repair in 6 and TV replacement in 4. TV was repaired by commissurotomy, annuloplasty or valvuloplasty, or combination of them. When residual significant tricuspid regurgitation (TR) and/or stenosis (TS) was detected by intraoperative pulsed Doppler echocardiography after reparative procedures, TV was replaced. Follow-up periods ranged from 1 to 12 years (mean, 45.3 months). There was no early death, and late death was noted in one patient 32 months after operation. Preoperatively, 7 patients were in NYHA class IV and 3 in class III. Out of survivors, 7 are in class I and 2 in class II because of progression of mitral stenosis or coronary artery disease. Following surgery, the patients exhibited significant decrease in the cardiothoracic ratio (69.3 +/- 7.2 to 56.9 +/- 6.4%; p less than 0.01) and in the mean right atrial pressure (11.4 +/- 3.6 to 8.6 +/- 3.1 mmHg; p less than 0.05). The postoperative right ventriculography showed mild to moderate TR in 3 of 6 patients who underwent TV repair. In conclusion, TV repair could be a reasonable procedure for the organic TV lesions, although careful follow-up is recommended for residual TR. 相似文献
78.
M Ohno T Yamamoto S Watanabe 《The Journal of pharmacology and experimental therapeutics》1992,263(3):943-950
In order to elucidate the roles of hippocampal N-methyl-D-aspartate-type excitatory amino acid receptors in working and reference memory in rats, the effects of intrahippocampal injections of selective and competitive N-methyl-D-aspartate receptor antagonists such as CGS 19755 (cis-4-phosphonomethyl-2-piperidine carboxylic acid), 3-[(+-)-2-carboxypiperazin-4-yl]propyl-1-phosphonic acid and 2-amino-5-phosphonovaleric acid on this behavior were examined with a three-panel runway task. The results were compared with the effect of the muscarinic receptor antagonist scopolamine. In the working memory task, CGS 19755 and 3-[(+-)-2-carboxypiperazin-4-yl]propyl-1-phosphonic acid at 10 and 32 ng/side, injected bilaterally into the dorsal hippocampus before testing, produced a significant increase in the number of errors (attempts to pass through two incorrect panels of the three panel-gates at four choice points). This also occurred after the rats were given systemic injection of these drugs at 3.2 and 10 mg/kg. In the reference memory task, neither CGS 19755 nor 3-[(+-)-2-carboxypiperazin-4-yl]propyl-1-phosphonic acid affected the number of errors, whether given at doses up to 32 ng/side intrahippocampally or up to 10 mg/kg systemically. Working memory errors also increased significantly after intrahippocampal injections of d-2-amino-5-phosphonovaleric acid at 100 and 320 ng/side, but were not affected by I-2-amino-5-phosphonovaleric acid at doses up to 1 microgram/side. On the other hand, intrahippocampal scopolamine at 1.0 and 3.2 micrograms/side increased significantly working memory errors, without affecting reference memory errors.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
79.
Pigeons were trained to perform simultaneous pattern and color discrimination tasks. After their training was completed, bilateral electrolytic lesions were made in the ventral lateral geniculate nucleus (GLv). Following the surgery, they were retrained to their preoperative performance levels. Lesions of GLv caused no deficits in pattern discrimination performance. The birds which had been trained for discrimination of red vs. magenta showed a slight decline in their performance. This impaired performance on color discrimination was not, however, as severe as that of a bird with lesions in the nucleus rotundus. These results suggest that GLv plays some role in the detection of short wavelengths of light. 相似文献
80.