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81.
Inhibition of HIV-1 infectivity with curdlan sulfate in vitro 总被引:5,自引:0,他引:5
Y Kaneko O Yoshida R Nakagawa T Yoshida M Date S Ogihara S Shioya Y Matsuzawa N Nagashima Y Irie 《Biochemical pharmacology》1990,39(4):793-797
Polymethoxylated flavones and C-glycosyl derivatives isolated from medicinal plants besides other flavonoid compounds were studied for their influence on lipid peroxidation induced by FeSO4+ cysteine in rat liver microsomes. A number of hydroxyflavones (e.g. luteolin); C-glycosyl-flavones (e.g. orientin); methoxyflavones (e.g. gardenin D) and flavonols (e.g. datiscetin), as well as the flavanol leucocyanidol and the biflavone amentoflavone behaved as inhibitors of non-enzymic lipid peroxidation. Structure-activity relationships were established and it was observed that the structural features for active polyhydroxylated compounds were different from those of polymethoxylated flavones, antiperoxidative flavonoids possessing a high lipophilicity. 相似文献
82.
83.
Y Kita Y Higashi M Kuze H Ito T Takeda H Takeuchi O Yoshida 《Hinyokika kiyo. Acta urologica Japonica》1992,38(3):277-280
Transurethral lithotripsy (TUL) was performed in the cases in which the ureteral calculi were not destroyed by the extracorporeal shock-wave lithotriptor (Dornier HM-3, EDAP LT 01). Preoperative placement of double-J ureteral catheter (D-J catheter) caused ureteral dilation, allowing smooth insertion of the ureteroscope. We divided the 55 TUL cases into two groups, those with (27) or without (28) a D-J catheter placed preoperatively, and compared requirement of ureteral bougination, difficulty of ureteroscope insertion and duration of operation between the two groups. In all cases with a D-J catheter, ureteral bougination was not necessary, the insertion of ureteroscope was easier and the duration of operation was shorter than the cases without a D-J catheter. Bladder irritable symptoms were seen in some cases with a D-J catheter but did not require removal of the D-J catheter. On the follow-up term after TUL, there was no difference in the incidence of postoperative fever or postoperative ureteral stenosis, between the cases with and those without a D-J catheter. 相似文献
84.
J Yoshida T Wakabayashi M Mizuno K Sugita H Seo M Oshima M Tadokoro S Sakuma 《Neurologia medico-chirurgica》1992,32(3):125-129
Iodine-131-labeled G-22 monoclonal antibody F(ab')2 fragment reaching specifically with a glioma-associated surface glycoprotein was administered to 12 glioma patients to investigate its use in radioimaging of intracranial gliomas. No immediate or delayed side effects were attributable to antibody injection. Nine patients received the radiolabeled complex intravenously. The images of low-grade gliomas were generally poor and disappeared within 4 days. High-contrast images were obtained beyond the 7th day in high-grade gliomas except one case in the pineal region. Three patients received intraventricular or intratumoral administration. Clear images of all tumors were demonstrated from the 2nd until later than the 7th day. One patient with cerebrospinal fluid (CSF) dissemination of brainstem glioma demonstrated negative CSF cytology after intraventricular administration. 相似文献
85.
Two variant cells lines resistant to the nitrosourea derivative ACNU ((1-4-amino-2-methyl-5-pyrimidinyl)-methyl-3-(2-chloroethyl)-3-nitrosourea hydrochloride), namely C6/ACNU and 9L/ACNU, were selected in vivo from rat brain tumors. Stable resistance to ACNU proved to be a characteristic of these cell lines, whether they were grown in vivo or in vitro. These cell lines exhibited a different pattern of cross-resistance to a wide range of chemotherapeutic agents with dissimilar chemical structures and mechanisms of action as compared with that of other ACNU-resistant cell lines established in vitro. Distinct cross-resistance was observed in both the C6/ACNU and 9L/ACNU cell lines to chloroethyl-nitrosoureas such as BCNU (carmustine), CCNU (lomustine), and methyl CCNU and, additionally, to vincristine, vinblastine, Adriamycin (doxorubicin), and arabinosylcytosine, but not to bleomycin, methotrexate, cis-platinum, and 5-fluorouracil. This might point to a multifactorial mechanism of drug resistance in ACNU-resistant cell lines derived from rat C6 and 9L brain tumor cells. 相似文献
86.
I Hisatome N Sasaki M Yamakawa M Kobayashi Y Tanaka H Kosaka A Yoshida H Kotake H Mashiba A Takeda 《Nephron》1992,61(2):196-199
Two patients with diabetes mellitus had persistent hypouricemia due to increased urate clearance; the degree of the apparent renal hypouricemia with uricosuria was quite mild. At the onset of diabetes, their serum urate levels were normal. Even after good diabetes control in both cases, hypouricemia continued. Based on the pharmacological evaluation in both patients, pyrazinamide administration could partially decrease urate clearance, however, suppression by pyrazinamide was less than in normal subjects, and probenecid increased urate clearance. These results suggest that the present cases had a renal abnormality affecting tubular presecretory reabsorption of urate, which might be due to diabetes mellitus. 相似文献
87.
We successfully performed arterial embolization of an arteriovenous fistula between the left gastric artery and vein. The increased blood flow in the portal vein via the left gastric vein and the arteriovenous fistula induced severe portal hypertension. After obliteration of the left gastric artery, the arteriovenous fistula was not opacified on angiography and the portal hypertension improved. 相似文献
88.
S M Pham Y Yoshida R Aeba B G Hattler Y Iwaki A Zeevi R L Hardesty B P Griffith 《The Journal of heart and lung transplantation》1992,11(6):1017-1024
Interleukin-6 (IL-6) is one of the cytokines produced by human alveolar macrophages, lung parenchyma, and other cells in response to injury and infection. We hypothesized that IL-6 is released from poorly preserved lung grafts and may serve as a marker of preservation injury. Sixteen patients who received lung allografts were enrolled in this study. The average ischemic time was 284 +/- 78 minutes. Serum IL-6 level was measured before and at 4 and 24 hours after reperfusion of the grafts by an enzyme-linked immunosorbent assay. Preservation injury was assessed by (1) the need for prolonged intubation (> 7 days), (2) the arterial/alveolar oxygen tension ratio (PaO2/PAO2 ratio) at 4 hours after graft reperfusion (only in heart-lung or double lung recipients), (3) the presence of diffuse alveolar damage on first lung biopsy, and (4) the 30-day graft survival rate. IL-6 level peaked at 4 hours after reperfusion and returned to baseline at 24 hours. The patients were divided into group I (n = 6) and group II (n = 10), depending on whether the 4-hour IL-6 level was more than 1000 pg/ml or less than 500 pg/ml, respectively. Group I patients required longer intubation (p < 0.01) and had a lower PaO2/PAO2 ratio (p < 0.001), more diffuse alveolar damage (p < 0.01), and a lower graft survival rate (p < 0.01) than those of group II. No bacterial, fungal, or viral infection was found during postoperative week 1 in either group.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
89.
S J Liu Q S Qu X P Xu Y T Liu S N Yin Y Takeuchi T Watanabe O Inoue M Yoshida M Ikeda 《American journal of industrial medicine》1992,22(3):313-323
A factory survey was conducted in three provinces in China from 1985 to 1989. The time-weighted average toluene concentrations in breathing zone air were monitored by diffusive sampling, whereas hippuric acid (HA) concentrations in shift-end urine samples were measured by high performance liquid chromatography (HPLC). Exposed workers (456 men and women) were those for whom toluene (up to 548 ppm toluene) accounted for greater than or equal to 90% of total exposure (by vapor concentration in ppm), whereas 517 nonexposed controls were recruited from the same factories or from factories of the same region. There was a linear correlation between the intensity of toluene exposure and HA concentration in the shift-end urine. Comparison of the results with findings in the literature shows that the toluene-induced increase in urinary HA concentration among workers in China is significantly smaller than the published values, whereas HA concentrations in urine samples from nonexposed controls are comparable to the levels previously reported. 相似文献
90.
Miya Yoshino Hidetoshi Yamazaki Hisahiro Yoshida Shumpei Niida Shin-Ichi Nishikawa Kazuo Ryoke Takahiro Kunisada Shin-Ichi Hayashi 《Journal of bone and mineral research》2003,18(1):108-116
Alveolar bone resorption by osteoclasts is essential for tooth eruption. Osteoclast-deficient Csfm(op) homozygous (op/op) mice, which lack functional macrophage colony-stimulating factor (M-CSF), suffer from osteopetrosis and completely lack tooth eruption. Although osteoclasts appear, and osteopetrosis is cured with age in op/op mice, tooth eruption is never seen. This fact suggests that there is a critical period when osteoclasts are required for tooth eruption. In this study, to detect the critical period, we administered an antagonistic antibody directed against c-Fms, a receptor for M-CSF, to inbred C57BL/6 mice for various periods. Administration of this antibody decreased tartrate-resistant acid phosphatase-positive (TRAP) osteoclasts, and incisor eruption was completely inhibited by continual administration of this antibody from embryonic day 15.5 (E15.5) until postnatal day 12.5 (D12.5). A 1-day delay of this administration abolished the inhibition of incisor eruption. The number of TRAP-positive osteoclasts was significantly reduced between E16.5 and E18.5 in the mice treated with antibody from E15.5 compared with those treated from E16.5. These results indicate that this period, during which the number of osteoclasts decreases significantly, is critical for inhibiting incisor eruption in C57BL/6 mice. 相似文献