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71.
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
72.
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
73.
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
74.
75.
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
76.
Treatment of Lethal Midline Granuloma Type Nasal T-Cell Lymphoma 总被引:7,自引:0,他引:7
Kohichi Sakata Masato Hareyama Atushi Ohuchi Mitsuo Sido Hisayasu Nagakura Kazuo Morita Yasuaki Harabuchi Akikatsu Kataura 《Acta oncologica (Stockholm, Sweden)》1997,36(3):307-311
Nasal T-cell lymphoma of the LMG type (LMG-NTL) is characterized by progressive, unrelenting ulceration, and necrosis of the nasal cavity and midline facial tissues. The clinical behavior of this tumor in 16 patients is compared with that of a nasal lymphoma of non-LMG-NTL type (non-LMG-NTL) in 8 patients and a paranasal sinus lymphoma (PSL) in 6 patients. All patients had stage I or II disease. Fourteen of the 16 patients with LMG-NTL received chemotherapy before and/or after radiotherapy. Cause-specific 5-year survival rates for patients with LMG-NTL, non-LMG-NTL, and PSL were 22%, 75%, and 67%, respectively. Seven patients with LMG-NTL, had complete response, although 3 recurred, whereas it was incomplete in 9 patients. The data indicates that it is desirable to deliver 50 Gy or more to achieve in-field control of LMG-NTL. 相似文献
77.
Radiotherapy of Vertebral Hemangiomas 总被引:2,自引:0,他引:2
Koh-Ichi Sakata Masato Hareyama Atushi Oouchi Mitsuo Sido Hisayasu Nagakura Mituharu Tamakawa Hidenari Akiba Kazuo Morita 《Acta oncologica (Stockholm, Sweden)》1997,36(7):719-724
Between 1975 and 1996, 14 patients (11 females, 3 males) with vertebral hemangioma received treatment with radiotherapy. Thirteen patients had a history of back pain or lumbago and 2 patients had neurological symptoms such as sensory impairment or paraplegia. The standard dose administered was 36 Gy in 18 fractions (five treatments per week). In the 13 patients with pain, this was completely or partially relieved. The condition of a man with hypesthesia of the legs deteriorated and a woman with paraplegia who was treated with decompressive laminectomy followed by radiotherapy recovered completely after irradiation. CT scan before irradiation showed thickened trabeculae as small punctate areas of sclerosis in all patients. At MR imaging before irradiation, T2-weighted MR images showed areas of high intensity in all patients and MR images demonstrated lesion enhancement. However, none of the patients who were treated successfully with radiation demonstrated any changes of the affected vertebra in the conventional radiographic films, CT scan or MR imaging, even 5 years after irradiation. Radiological imaging is indispensable for the diagnosis of vertebral hemangiomas but does not appear to be useful for evaluating the effects of radiotherapy. 相似文献
78.
In epidemiologic studies, many serum samples obtained from a large population have to be processed for measurement of fat-soluble vitamins. Quantification results by a high performance liquid chromatography (HPLC) should be stable in both intra- and inter-run, and a quality control may be performed by a X-R control chart. The present study shows that serum retinol, alpha-tocopherol, alpha-carotene, beta-carotene, and lycopene could be measured simultaneously, by 1) use of photodiode-array (POD) detector, 2) selection of some optimal analytical conditions (e.g. column, mobile phase, column temperature), 3) applying 2 internal standards, and 4) monitoring by a X-R control chart. The present procedure yielded relatively low coefficients of variations (CVs) compared to some reported figures. However, determination of CVs only does not ensure the accuracy and precision of an assay system, and application of a X-R control chart may be necessary for a good quality control of measurement, such as serum fat-soluble vitamins. 相似文献
79.
The neural basis of individual differences in behavior has been studied primarily by analyzing the properties of specific neural areas. However, because of the organization of the nervous system, it is also plausible that differences in behavior are mediated by differences in the interactivity or functional connectivity among brain nuclei in particular neural circuits. In the leopard gecko, Eublepharis macularius, the temperature of the egg during incubation not only determines gonadal sex, but also shapes the sociosexual behaviors, reproductive physiology, and hormone sensitivity of adult animals. In this study the effects of both incubation temperature and gonadal sex on functional connectivity among limbic brain areas were examined. Functional connectivity was assessed by analyzing covariance patterns in metabolic capacity, as revealed by quantitative cytochrome oxidase histochemistry. It was hypothesized that incubation temperature and gonadal sex affect the propensity to display aggressive or sexual behaviors by altering the functional connectivity within relevant neural circuits. The correlations of metabolic capacity between the anterior hypothalamus and both the septum and preoptic area were significant only in relatively aggressive individuals, suggesting that these circuits may regulate the phenotypic variation in aggressiveness caused by incubation temperature. The correlations between the ventromedial hypothalamus and both the dorsal ventricular ridge and septum were significant only in females, suggesting that these circuits may modulate female-typical sexual behaviors. Correlations among preoptic, hypothalamic and amygdalar areas tended to be distributed across both sexes, suggesting that there may be shared pathways underlying the expression of male-typical and female-typical behaviors. 相似文献
80.
We previously reported that brain angiotensin II type 2 (AT2) receptors contribute to the hyperthermia induced by intrahypothalamic (intrapreoptic (i.p.o.)) administration of prostaglandin E2 (PGE2) in rats. The present study was carried out to investigate the role of angiotensin II (ANG II) receptors in the cardiovascular and adrenocorticotropic hormone (ACTH) responses induced in rats by i.p.o. injection of PGE2. PGE2 (100 ng) produced marked increases in blood pressure, heart rate, and plasma ACTH concentration. These changes were significantly enhanced by i.p.o. treatment with an AT1-receptor antagonist, losartan, while an AT2-receptor antagonist, CGP 42112A, had no effect. In contrast, losartan, but not CGP 42112A, reduced the pressor and ACTH responses to i.p.o. injection of a large dose of "exogenous" ANG II (25 ng). These results suggest that while "endogenous" ANG II exerts inhibitory effects on both the cardiovascular and the ACTH responses to i.p.o. PGE2 by way of preoptic AT1-receptors, a large dose of exogenous ANG II produces effects opposite to those induced by the endogenous ANG II that is released locally and in small amounts by i.p.o. PGE2. 相似文献