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151.
The dominant non-gibberellin-responding dwarf mutant (D8) of maize accumulates native gibberellins 总被引:9,自引:1,他引:9 下载免费PDF全文
Fujioka S Yamane H Spray CR Katsumi M Phinney BO Gaskin P Macmillan J Takahashi N 《Proceedings of the National Academy of Sciences of the United States of America》1988,85(23):9031-9035
The endogenous gibberellins (GAs) were examined from young vegetative shoots of the dominant mutant, Dwarf-8, a GA-nonresponder, and normal maize; GA44, GA17, GA19, GA20, GA29, GA1, and GA8, members of the early-13-hydroxylation pathway, were identified from both kinds of shoots by full-scan mass spectra and Kovats retention indices. In addition, we report the identification of 3-epi-GA1, GA3, GA4, GA5, GA7, GA9, GA12, GA15, GA24, GA34, and GA53 by using the same criteria. [1,7,12,18-14C4]GA53 and -GA44, [17-2H2]GA19, and [17-13C,3H2]GA20, -GA29, -GA1, -GA8, and -GA5 were used as internal standards to determine the endogenous levels of these GAs by measurement of isotope dilution, using capillary gas chromatography and selected ion monitoring. Shoots of Dwarf-8 accumulate relatively high levels of GA20, GA1, and GA8. The accumulation of GA1 appears to be related to gene dosage. Since Dwarf-8 contains the same pattern of GAs as normals (including GA1 and GA3), the genetic control point probably lies after GA1 (and GA3). Thus Dwarf-8 may be a GA receptor mutant or a mutant that controls a product downstream from the binding of the bioactive GA to a receptor. 相似文献
152.
Effects of season, temperature, and photoperiod on plasma melatonin rhythms in the goldfish, Carassius auratus 总被引:1,自引:0,他引:1
Abstract: Effects of season, environmental temperature, and photoperiod on plasma melatonin concentrations were studied in the goldfish, Carassius auratus. When goldfish were reared under natural conditions, melatonin levels at mid-dark exhibited seasonal changes, with higher levels obtained in June and September than in December and March. When fish were kept under light: dark (LD) cycle of 12: 12 at 5, 15, or 25°C during March-April, temperature-dependent increases in melatonin levels at mid-dark were observed. When animals were maintained under LD 16: 8 or LD 8: 16 in combination with temperature changes (5, 15, and 25°C) during January-February, the duration of nocturnal elevation in melatonin was controlled by the length of the scotophase while the amplitude was influenced by environmental temperature. These results indicate that plasma melatonin profiles in the goldfish exhibit seasonal changes that are regulated by both photoperiod and temperature. 相似文献
153.
Caliskan D Oncu B Kose K Ocaktan ME Ozdemir O 《Journal of psychosomatic obstetrics and gynaecology》2007,28(4):195-200
The aims of this study were to evaluate and compare the depression scores of pregnant and non-pregnant women, and to identify the factors associated with depression scores in the two groups. This community-based study was conducted in a primary health care center catchment area in Ankara (population: 17,838) in January 2003. At the beginning of the study, the trimesters of all pregnant women (n = 66) were determined and as a control group (n = 138), two non-pregnant women matched for age and parity characteristics living in the same area were selected for each pregnant woman. Each participant completed a questionnaire and the Beck Depression Inventory (BDI). One-way ANOVA, univariate correlation, and multiple linear regression analyses were used in statistical evaluation. Depression scores of pregnant and non-pregnant women, and women at different trimesters of pregnancy were similar. Using a cut-off score > or = 18 on the BDI, 26.5% of non-pregnant women, 27.3% of pregnant women, 25.0% of pregnant women in their first and second trimester, and 30.0% of third trimester pregnant women were found to be depressive. According to multiple linear regression analysis, age, age at marriage, and the number of people living in the home were associated with depression in both groups. Depression scores were similar in pregnant women and non-pregnant controls. There were different associations between depression score and the study groups' characteristics. 相似文献
154.
Origuchi T Arima K Kawashiri SY Tamai M Yamasaki S Nakamura H Tsukada T Aramaki T Furuyama M Miyashita T Kawabe Y Iwanaga N Terada K Ueki Y Fukuda T Eguchi K Kawakami A 《Modern rheumatology / the Japan Rheumatism Association》2012,22(4):584-588
Recently, it was reported that remitting seronegative symmetrical synovitis with pitting edema (RS3PE) syndrome could be complicated with solid tumors. In a retrospective, multicenter study between October, 2003 and September, 2010, we investigated the characteristics of patients with paraneoplastic RS3PE syndrome who fulfilled following criteria: (1) bilateral pitting edema of hands or feet or both, (2) sudden onset of polyarthritis, and (3) age >50?years, (4) seronegativity for rheumatoid factor (RF). A total of 33 cases fulfilled the above criteria. Eight patients (seven men and one woman) developed cancer within 2?years of RS3PE syndrome onset. There was no significant difference between the neoplastic and nonneoplastic groups in the proportions of patients with fever, symmetrical polyarthritis, pitting edema, and good response to corticosteroids. Serum matrix metalloproteinase 3 (MMP-3) level (median 437.3?ng/ml) in the paraneoplastic RS3PE patients was significantly higher than that in patients without neoplasia (median 114.7?ng/ml) (p?0.05). We found that high serum MMP-3 is characteristic of patients with paraneoplastic RS3PE syndrome. 相似文献
155.
Ken Tanigawa Katsumi Eguchi Yoshio Kitamura Atsushi Kawakami Hiroaki Ida Shunichi Yamashita Naofumi Matsunaga Kuniaki Hayashi Shigenobu Nagataki 《Arthritis \u0026amp; Rheumatology》1992,35(4):476-480
Objective. Early diagnosis of Takayasu arteritis in the acute stage (prepulseless stage) is extremely difficult. Identification of a useful approach to detecting the initial changes of arteritis is therefore desirable. Methods. Careful clinical examination of a young woman with persistent fever and dry cough revealed faintly audible bruits at the cervical, supraclavicular, and abdominal regions. Aortographic features suggested thickening of the wall of the descending thoracic aorta. Magnetic resonance imaging (MRI) of this area was diagnostic. Results. MRI demonstrated involvement of the ascending aorta and right main pulmonary artery. Steroid therapy (prednisolone 60 mg/day) induced dramatic clinical and radiologic improvement in 2 months. Conclusion. This is the first report of MRI-documented reduction in the thickness of the walls of both the aorta and the pulmonary artery following steroid therapy. 相似文献
156.
Harutoshi Matsumoto Saeko Ando Eri Yoshimoto Takamasa Numano Nahida Sultana Katsumi Fukamachi Munekazu Iinuma Kensuke Okuda Kazunori Kimura Masumi Suzui 《Oncology Letters》2022,23(3)
Musa basjoo (MB) is a species of the banana plant belonging to the genus Musa that has been used as a folk medicine. However, evidence-based biological activities and the molecular mechanism of action of MB are unknown. Thus, the aim of the present study was to examine whether the crude dried leaf extracts of MB inhibit the growth of colorectal (HT29 and HCT116) and other types (HepG2, MCF-7 and PC-3) of human cancer cell lines. Crude extracts of MB inhibited the growth of cells with IC50 values of 136 µg/ml (acetone extract, HT29), 51 µg/ml (acetone extract, HCT116), 45 µg/ml (acetone extract, HepG2), 40 µg/ml (acetone extract, MCF-7), 29 µg/ml (acetone extract, PC-3), 175 µg/ml (methanol extract, HT29), 137 µg/ml (methanol extract, HCT116), 102 µg/ml (methanol extract, HepG2), 85 µg/ml (methanol extract, MCF-7), and 85 µg/ml (methanol extract, PC-3) in colony formation assays, and 126 µg/ml (acetone extract, HT29), 68 µg/ml (acetone extract, HCT116), 260 µg/ml (methanol extract, HT29), and 216 µg/ml (methanol extract, HCT116) in MTT assays. Thin layer chromatography analysis revealed the potential existence of aromatic compounds in the acetone extract of MB. Flow cytometric analysis indicated that the percentage of cells in G1 increased, and this was associated with a concomitant decrease of cells in the S and/or G2-M phases of the cell cycle. When colorectal cancer cells were treated with acetone extract of MB, there was a marked decrease in the levels of expression of the cyclin D1, cyclin E, cdk2 and cdk4 proteins and a marked increase in the levels of the expression of the p21CIP1, p27KIP1, and p53 proteins, but those of apoptosis-associated protein PARP did not change. There was a tendency for acetone extract of MB to inhibit xenograft tumor growth in mice. Collectively, the crude extracts of MB contain active components that exert growth inhibition of human cancer cells. This is the first systematic study of the anticancer activity of MB and may broaden insights into the possible clinical approach of specific herbal medicines. 相似文献
157.
Katsumi Eguchi Tomoki Origuchi Hiroyuki Takashima Kokichi Iwata Shigeru Katamine Shigenobu Nagataki 《Arthritis \u0026amp; Rheumatology》1996,39(3):463-466
Objective. To investigate the association between human T lymphotropic virus type I (HTLV-I) infection and rheumatoid arthritis (RA) in Nagasaki, an area highly endemic for HTLV-I infection. Methods. Sera from 113 female patients with RA and 19,796 female blood donors were screened for anti–HTLV-I antibodies with a gelatin particle agglutination kit and confirmed using an immunoblotting kits. Results. The age-adjusted summary odds ratio of HTLV-I infection among RA patients, as compared with blood donors, was 2.8 (95% confidence interval [95% CI] 1.8–4.6). The etiologic fraction, i.e., the proportion of RA in the study population that is attributable to HTLV-I infection, was estimated to be 13.2% (95% CI 5.1–21.2). There was no significant difference in the clinical and laboratory findings between HTLV-I–infected and HTLV-I–uninfected RA patients. Conclusion. These epidemiologic findings support the idea that HTLV-I infection is a risk factor for RA, and suggest that ∼13% of the cases of RA in females living in Nagasaki are associated with HTLV-I infection. 相似文献
158.
159.
160.
Hideyuki Ogawa Toshiyuki Ishikawa Kouhei Matsushita Katsumi Matsumoto Tomoaki Ishigami Teruyasu Sugano Kazuaki Uchino Satoshi Umemura Shinichi Sumita Kazuo Kimura Takeshi Nakagawa Makoto Shimizu Hideo Nishikawa Atsunobu Kasai Yukio Kioka 《Circulation journal》2008,72(5):700-704
BACKGROUND: Several preliminary studies have indicated that atrial pacing can prevent atrial tachyarrhythmias. The suggested mechanisms by which pacing may be effective include suppression of premature atrial beats. METHODS AND RESULTS: The Atrial Pacing Preference (APP; Guidant, St Paul, MN, USA) algorithm allows the pacemaker to maintain a pacing rate slightly higher than the sinus rate. The preventive effects of APP on paroxysmal atrial fibrillation (AF) were studied in 51 patients (70+/-11 years). Nine patients did not complete the protocol. The pacemaker was programmed in random order to APP off and APP on at 3 different settings (ie, 8, 16 and 32 cycles) for 4 weeks each, using a cross-over design. Percentage atrial pacing was lower in APP off than at the other settings. Premature beat counts were greater in APP off than at the other settings. There was a significant difference in mode switch episode counts between APP off and the most effective setting (3,818+/-15,356 vs 596+/-1,719; p<0.01). CONCLUSIONS: The APP algorithm is a promising method for preventing atrial tachyarrhythmia in patients with an implanted pacemaker and AF. Optimizing the setting of the APP algorithm is an important issue in the prevention of AF. 相似文献