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71.
Yoshimatsu H Itateyama E Kondou S Tajima D Himeno K Hidaka S Kurokawa M Sakata T 《Diabetes》1999,48(12):2286-2291
72.
The authors examined the effect of bilateral jugular vein ligation (JVL) on local cerebral blood flow (CBF). Local CBF was measured in the neocortex of the frontal lobe over a 1-week period in 10 freely moving male rats. Measurements were taken with the hydrogen clearance method before and after the rat underwent either an operation of bilateral JVL or a sham operation. After the sham operation, blood flow values did not change significantly compared with preoperative values. Blood flow values decreased rapidly in rats with JVL. For 3 hours after surgery, JVL values were significantly lower (p <0.05) than preoperative values were, then gradually they recovered and reached preoperative values within 48 hours. Histopathologic study showed no remarkable parenchymal damages in the brain of rats with JVL. These results show that bilateral JVL produces a reversible decrease in the CBF and does not cause histopathologic brain damages. 相似文献
73.
Takeda T Sakata A Matsuoka T 《Progress in neuro-psychopharmacology & biological psychiatry》1999,23(6):1157-1169
1. Occurrence of miniature endplate potentials (MEPP) in the sartorius muscle of Rana catesbiana in high Mg2+ Ringer solution were observed in standard intracellular recording. Intervals and amplitudes of sequentially occurring MEPP were registered and analyzed. 2. Interval histograms of a time series of MEPP showed exponential-like pattern as reported in the classical study by Fatt and Katz (1952). The cumulative distribution of the intervals plotted in logarithmic axes showed two distinct phases. In shorter intervals (< 1s), curve along exponential decay was observed, and in longer intervals (> or = 1s) linear decay can be seen. The latter power-law relation gave dimensions of 4.111 +/- 0.812 (mean and S.D.). Self-similarity in longer range implies a time-scale invariant nature and may suggest fractal nature in restoration process of synaptic vesicles, while exponential decay in the short time interval range implies random release of transmitter packet from the readily releasable pool. 3. Fluctuation of amplitudes in sequentially occurred MEPP were analyzed according to Higuchi's cumulative route-length analysis. The estimates for sequential amplitude curve showed the power-law relation in a logarithmic plot whose inclination (= D) estimated with linear regression analysis was 1.996 +/- 0.007 (mean and S.D.). This results indicate that fluctuation in the amplitude of MEPP shows possible maximum complexity as a graphic curve in 2-D plane. Similar result was obtained for fluctuation of intervals of successively occurring MEPP. 相似文献
74.
BACKGROUND/AIM: An angiolipoma is a common benign neoplasm with a characteristic vascular component that occurs in the subcutaneous tissue and rarely in the gastrointestinal tract. We report on a 69-year-old man with a submucosal angiolipoma in the cecum. METHODS: This patient was treated with a laparoscopy-assisted ileocecostomy, and a side-to-side anastomosis was performed extracorporeally. RESULTS: A light microscopic study supported the diagnosis of an angiolipoma of the colon. After 5 years of follow-up, the patient has no symptoms or signs of recurrence. CONCLUSION: The colonic angiolipoma was successfully removed using a minimally invasive laparoscopic technique. Copyright Copyright 1999 S. Karger AG, Basel 相似文献
75.
Yamasaki K Kaneko M Matsuda K Sakata SF Tamaki N 《Journal of nutritional science and vitaminology》1999,45(5):621-632
The characteristic cyclic variation in feed intake of rats fed a Zn-deficient diet (Mills et al, Am J Clin Nutr 22: 1240-1249 (1969)) followed a Cosinor curve, as determined by computer analysis (Tamaki et al, Br J Nutr 73: 711-722 (1995)). The values of amplitude for the feed-intake cycle had a positive correlation to their own day-to-day variations and to the correlation value of their own simulated cycles (r2 = 0.764, df = 50, p < 0.001 and r2 = 0.682, df = 50, p < 0.001, respectively). The cyclic variation in feed intake was accompanied by a cyclic variation in body-weight change in rats fed the Zn-deficient diet, and cyclic variation in body-weight change occurred similarly in pair-fed control rats. There were no differences in the mesors of body-weight change cycles of Zn-deficient rats and pair-fed control rats (Zn-deficient rats: 2.5 +/- 1.0 g/d, pair-fed rats: 2.8 +/- 1.0 g/d, mean +/- SD, df = 18, t = -0.674, ND). Rats fed the Zn-deficient diet were given different amounts of Zn supplementation by daily subcutaneous injection. The amplitude of the feed-intake cycle was decreased with increasing Zn supplementation (r2 = 0.919, df = 5, p < 0.001). The concentration of Zn for the appearance of the feed-intake cycle was estimated to be 71.6 +/- 6.6 micrograms/d per rat. The Zn level in the serum showed a significant decrease in the Zn-deficient diet groups, but the supplement of Zn did not vary in the Zn-deficient rats injected with up to 47.3 micrograms/d per rat. From these results, an analysis of the feed-intake cycle allowed us to estimate the quantitative Zn-deficient status of rats. 相似文献
76.
Seasonal variation of saponins, sucurose and monosaccharides in cultivated ginseng roots 总被引:1,自引:0,他引:1
Yield of methanolic extract of fresh roots of Ginseng harvested in winter was found to be more than two-fold grater than from roots collected in summer; this remarkable increase is mainly due to the large increase of sucrose in roots in winter. On the other hand, biologically active dammarane-saponins in the roots increase in summer. These results indicate that roots should be harvested in summer for the production of high quality Ginseng extracts. 相似文献
77.
Tsuda Hiroyuki; Sakata Takao; Tamano Seiko; Okumara Masanao; Ito Nobuyuki 《Carcinogenesis》1983,4(5):523-528
Sequential observations were carried out on the induction ofpreneoplastic lesions in the liver and the kidney. Rats wereinitially given N-ethyl-N-hydroxyethylnitrosamine (EHEN) intheir drinking water (0.1%) for 3 days (Group 1), 1 week (Group2) or 2 weeks (Group 3) or tap water (Group 4). Rats in Groups1 3 were subjected to partial hepatectomy and unilateralnephrectomy (right side) 2 weeks after the end of EHEN treatment.Rats from these groups were killed in week 10, 20, 30 and 40of the experiment. In the liver, the effect of EHEN in the inductionof -glutamyltranspeptidase (-GT) positive foci and hyperplasticnodules (HN) was clearly dependent on the length of treatment.The preneoplastic lesions increased with the lapse of observationtime. Changes measured as number of -GT positive foci were 1040times greater than those measured as HN, especially among thesmall size range. Values for changes in Group 1 given 0.1% EHENfor 3 days were very low, indicating that this dose is closeto the threshold. Two rats with hepatocellular carcinoma inGroup 3 given EHEN for 2 weeks survived until week 40. In thekidney, tubular epithelial proliferations composed of cellswith slightly basophilic cytoplasm and slightly atypical nucleiwere tentatively named atypical cell foci (ACF). EHEN inducedACF, renal cell adenomas and renal cell carcinomas. The increasein the induction of ACF was dependent on the length of observationperiod but not on the length of treatment. Even though controlrats (not treated with EHEN) also had ACF, their quantitativevalues were far less than the groups given EHEN and killed atweek 40, indicating that a large number of ACF were inducedby EHEN. Therefore, EHEN is good for experimental inductionof preneoplastic lesions in the liver and kidney of rats. Theexperimental schedule for Groups 1 and 2 could be used as ashort-term screening test for promoters and the schedule forGroup 3 as an assay for inhibitors. 相似文献
78.
T Motohiro M Aramaki K Oda A Kawakami T Koga S Tomita Y Sakata F Yamashita K Tanaka Y Matsukuma 《The Japanese journal of antibiotics》1992,45(12):1684-1699
Cefprozil (CFPZ), a newly developed cephalosporin in fine granular form, was administered to pediatric patients with skin and soft tissue infections. MICs were determined for 6 drugs including CFPZ, cephalexin (CEX), cefaclor (CCL), ampicillin (ABPC), methicillin (DMPPC), cloxacillin (MCIPC) against 53 clinical isolates of Staphylococcus aureus from these patients. An inoculum size of 10(6) CFU/ml was used in the MIC-determinations. CFPZ was given to 73 patients with ages ranging from 6 months to 10 years and 8 months and 71 cases were evaluable for clinical effects as follows; impetigo (65), Staphylococcal scalded skin syndrome (1), furuncle (1), subcutaneous abscess (3), and periproctal abscess (1). To study clinical efficacy, bacteriological effects and safety of this drug, a mean dose of 8.4 mg/kg with 3-4 daily dosages (57 cases of t.i.d. and 14 cases of q.i.d.) was administered for an average of 6 days. The results obtained are summarized as follows. 1. With regard to the 53 isolates of S. aureus, MICs of CFPZ against 52 strains (98.1%) ranged from 0.78 to 3.13 micrograms/ml. 45 strains (84.9%) were inhibited at 0.78 micrograms/ml. MIC90 of CFPZ was 1.56 micrograms/ml, but MIC against 1 strain of Methicillin-resistant S. aureus (MRSA) was 100 micrograms/ml. The MIC90 of CEX and CCL were 6.25 micrograms/ml and MIC of CEX and CCL against 1 MRSA strain were 200 and 100 micrograms/ml, respectively. The MIC90 of ABPC, DMPPC and MCIPC were 6.25, 3.13 and 0.39 micrograms/ml, respectively. CFPZ showed the second highest activity after MCIPC against S. aureus. 2. CFPZ showed very good clinical responses and clinical effects in 71 patients all of whom judged by doctors in charge as having "good" or better responses. 3. For impetigo patients, the evaluable cases by score 3, 5 and 7 days after administration of the drug were 52, 39 and 20 patients, respectively. The efficacy rates on these days were 90.4, 100 and 100%, respectively. The efficacy rate at a daily dose of 30.1-45.0 mg/kg on day 3 was 17.2% higher than that at 22.5-30.0 mg/kg, and the "excellent" response rate of 30.1-45.0 mg/kg group was 45.3% greater. Because of these results, it is expected that good clinical effects can be obtained at a daily dose of 22.5-30.0 mg/kg of CFPZ, but better responses can be expected at 30.1-45.0 mg/kg in 3-4 divided doses given for 5 days. 4. Bacteriological effects of CFPZ were determined against 60 strains of S. aureus.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
79.
80.
Yasuhide Yamada Yuh Sakata Kenichi Tsushima Taro Satoh 《International journal of clinical oncology / Japan Society of Clinical Oncology》1997,2(1):10-14
Background We studied the relationship between the augmentative effects of leucovorin (LV) on 5-fluorouracil (5-FU) and the inhibition
rate of thymidylate synthase (TS) activity in Colon 26 murine colon carcinoma cells and L1210 murine leukemia cells.
Methods In cytotoxic and TS inhibition studies, cells were exposed for 24 hours to varied concentrations of 5-FU alone or in combination
with 1 or 10 μmol/L LV. Cytotoxicity was determined by colony forming efficiency or trypan blue dye exclusion, and TS inhibition
rate was determined by [6-3H]-5-FdUMP binding assay. A growth inhibition curve was constructed for longer exposures.
Results For tumor cell growth inhibition and cytotoxicity, the augmentative effect was observed when the lower 5-FU concentrations
(0.1 μg/mL) were used. There was no difference in the effects between the low (1 μmol/L) and high (10 μmol/L) LV doses. Normally,
TS enzyme levels rise acutely when cells are exposed to 5-FU. Both cell lines displayed an increase in TS after exposure to
5-FU. This exposure to 5-FU resulted in the maintenance of free enzyme. LV was able to increase the ternary complex and TS
inhibition rate with little induction of TS, however, the inhibition rate was not dependent on doses of LV.
Conclusions It was concluded that the augmentative effect of LV at a concentration of 0.1 μg/mL 5-FU occurred at the clinically achievable
levels of 1 μmol/L of LV, and there was no difference in the effect between the low and high doses. TS was inhibited effectively
by 5-FU and the addition of LV, without a marked induction of TS. 相似文献