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991.
D K Swanson P D Myerowitz B Hasegawa M S Van Lysel K M Watson D W Frantz S Banaszak E Hausman-Stokes W W Peppler J T Dobbins 《The Journal of surgical research》1983,34(6):524-532
Standard angiography demonstrates the anatomy of arterial occlusive disease but does not define its physiological significance. However, measurement of flow in a compromised vessel at rest and following peripheral dilatation provides important physiological information. Using digital subtraction angiography, femoral arterial flows determined by the cross-correlation transit time technique were compared to measurements by electromagnetic flowmeter. Thirty-five femoral arterial flow measurements were obtained in nine dogs instrumented with an electromagnetic flow probe and balloon occluder. Renografin 76 (7 cc) was power-injected at 14 cc/sec into the distal abdominal aorta. Angiographic flow measurements correlated well with electromagnetic flowmeter measurements (r = 0.94, standard deviation of the difference (SDD) = 15 ml/min). Intravenous studies provided somewhat poorer correlation due to difficulties in defining dimensions (r = 0.72, SDD = 36). Paired contrast injections (2 injections in succession) in 11 studies increased flow from an average of 80 to 250 ml/min (a 210 +/- 100% increase), providing an estimate of a vessel's capacity to provide increased flow during peripheral dilatation. Thus, reliable angiographic flow determinations may be obtained by arterial and intravenous contrast injections, adding physiological information to anatomical definition. 相似文献
992.
993.
Changes in distribution of hepatic blood flow induced by intra-arterial infusion of angiotensin II in human hepatic cancer 总被引:7,自引:0,他引:7
Y Sasaki S Imaoka Y Hasegawa S Nakano O Ishikawa H Ohigashi K Taniguchi H Koyama T Iwanaga T Terasawa 《Cancer》1985,55(2):311-316
Changes in the distribution of the hepatic blood flow induced by intra-arterial infusion of angiotensin II (AT-II) were studied in human hepatic cancers using extremely short-lived radioisotope (RI) (krypton 81 m [81mKr]; half-life, 13 seconds). After the start of continuous infusion of AT-II, the radioactivity of the tumor showed about a two-fold increase, whereas that of the nontumor region decreased to about one half as much as the level before the infusion. Consequently, the mean ratio of the arterial blood flow in the tumor region to that in the nontumor region (T/N ratio) increased to 3.30 (P less than 0.001). The T/N ratio showed a peak before the peripheral blood pressure reached the maximum, and thereafter tended to decrease. Intra-arterial infusion of AT-II raised the T/N ratio more obviously than did intravenous infusion of the drug, with less rise in the peripheral blood pressure. It is believed that intra-arterial infusion chemotherapy with local use of AT-II enables better accessibility of chemotherapeutic drugs to tumors. 相似文献
994.
Glucocorticoids were injected sc into rat foetuses through the uterine wall on day 19 of intrauterine development; two days later the foetuses were removed and their adrenal glands were weighed. Some betamethasone derivatives produced marked adrenal hypertrophy in the foetuses. Structural characteristics of the effective compounds were 17alpha-esterification and 16beta-methylation. 9alpha-Halogenation and 21-esterification of glucocorticoids were not essential for producing the hypertrophy. Propionic acid at the C-17 position was more effective than valeric and acetic acids in producing the hypertrophy. The effect of betamethasone 17, 21-dipropionate was dose-responsive and prevented by simultaneous administration of betamethasone 21-disodium phosphate. Results obtained with decapitated or encephalectomized foetuses suggested that the hypertrophy produced was not due to a direct action of the glucocorticoids on the adrenal gland, but mediated by the hypothalamo-pituitary system. 相似文献
995.
996.
Comparative studies on antitumor activity of Klebsiella O3 lipopolysaccharide and its polysaccharide fraction in mice 总被引:2,自引:0,他引:2
T Hasegawa M Ohta N Kido N Kato K Miyamoto R Koshiura 《Japanese journal of pharmacology》1985,38(4):355-360
The antitumor activity of the polysaccharide fraction (OPS) obtained by the acid hydrolysis of Klebsiella O3 lipopolysaccharide (KO3 LPS) isolated from the culture supernatant of the decapsulated mutant strain LEN-1 (03: K1-) against both allogeneic tumor and syngeneic tumor systems in mice was compared with that of KO3 LPS. OPS prolonged the life span of MM2-bearing C3H/He mice by intraperitoneal (i.p.) pre- and post-treatment at the doses of 100 and 1000 mg/kg. However, large amounts of OPS were needed to show the antitumor activity as compared with KO3 LPS. OPS showed no growth inhibitory activity against Meth-A sarcoma in BALB/c mice by i.p., intravenous (i.v.) or intratumoral (i.t.) administration. When 1000 mg/kg of OPS was i.p. administered once a day for 10 days, OPS significantly inhibited the tumor growth of Sarcoma-180 solid type tumor. On the other hand, KO3 LPS significantly suppressed the growth of Meth-A tumor by i.t. administration at the doses of 0.3 and 1.0 mg/kg and showed complete regression in 8 and 9 out of 10 mice, respectively. In MM2 tumor, KO3 LPS also showed complete regression in all mice post-treated by i.p. administration at the dose of 1.0 mg/kg. These results suggest that OPS has antitumor activity on the tumors used in this study, but the activity was less than that of KO3 LPS. 相似文献
997.
F Taguchi K Hasegawa D Nagaki 《The Kitasato archives of experimental medicine》1966,39(1):Suppl:1-Suppl:2
998.
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