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141.
A new indole alkaloid glucoside, named palicoside, has been isolated from the leaves of PALICOUREA MARCGRAVII (Rubiaceae) collected in Brazil. The structure was established by spectroscopic methods and its chemical conversion to strictosamide. 相似文献
142.
T Watanabe H Matsuki T Ogawa Y Kawanishi H Kasuga 《The Tokai journal of experimental and clinical medicine》1989,14(5-6):367-373
Inhibition ELISA assay was used to examine the cross-reaction of the polyclonal anti-desmosine antiserum produced in rabbit against molecules possessing a "pyridinium ring" as their core structure i.e. isodesmosine, pentasine, pyridinoline and 2'-deoxypyridinoline, highly purified with column chromatography, and structurally unrelated substances, i.e. cysteic acid, taurine and 2-aminopyridine (core structure of desmosine). No cross-reaction was observed to the pyridinoline, 2'-deoxypyridinoline possessing "pyridinium ring" and derived from collagen cross-links, structurally unrelated cysteic acid and taurine, nor core structure of 2-aminopyridine. The antiserum specifically recognized the molecules derived from the elastin cross-links. Using the ELISA assay system with antisera and amino acids analysis, 10 micrograms of desmosine were extracted from 1.0 mg of the hydrolysate of commercial elastin. 相似文献
143.
144.
A case of leiomyoma of the lamina muscularis mucosae of the esophagus with a complication of carcinoma in situ of the overlying mucosa 总被引:3,自引:0,他引:3
An extremely rare case of leiomyoma originating in the lamina muscularis mucosae of the esophagus with a complication of carcinoma in situ in its overlying mucosa was reported. The patient was a 53-year-old male who complained of a feeling of abdominal fullness. A small, elevated tumor was found in the middle portion of the esophagus by esophagoscopy. Biopsy specimens showed it to be squamous cell carcinoma. The resected material revealed the tumor mass to be composed of both a leiomyoma, measuring 0.8 x 0.6 x 0.25 cm, which continued from the lamina muscularis mucosae, and carcinoma in situ and dysplasia in the overlying mucosa of the leiomyoma. The mucosa apart from that covering the leiomyoma was intact. It was speculated that chronic stimulation of the epithelium covering the leiomyoma might have induced the dysplasia and carcinoma in situ. 相似文献
145.
Shimazoe T Nakamura S Kobayashi K Watanabe S Miyasaka K Kono A Funakoshi A 《Neuroscience》2004,123(1):201-205
The role of 5-HT1A and 5-HT1B receptors in entrainment function was studied in Otsuka Long Evans Tokushima fatty (OLETF) rats and control Long Evans Tokushima Otsuka (LETO) rats. Light-induced (100 lux, 30 min) Fos expression in the suprachiasmatic nucleus was studied. Light-induced Fos expression was significantly decreased in OLETF rats compared to that in LETO rats. The decrease of light-induced Fos expression in OLETF rats was significantly reversed by pretreatment with the 5-HT1B receptor antagonist, isamoltan (3 mg/kg, i.p.). Simultaneous administration of CGS12066B (5 mg/kg, i.p.), a 5-HT1B agonist, blocked the reversal effect of isamoltan on Fos expression. Fos expression was not changed in LETO rats by pretreatment with isamoltan (3 mg/kg, i.p.). The Fos expression in LETO and OLETF rats was significantly decreased by pretreatment with the 5-HT1A antagonist, WAY-100,635. Phase shifts in locomotor activity paralleled the Fos expression. Light-induced phase shifts of locomotor activity in OLETF rats were significantly smaller than those in LETO rats. The phase shifts were significantly increased by isamoltan (3 mg/kg, i.p.) in OLETF rats. These results suggest that 5-HT1B receptors are involved in the reduced entrainment function of OLETF rats. 相似文献
146.
Mika Tanaka Masahiro Umezaki Kazumi Natsuhara Taro Yamauchi Tsukasa Inaoka Tetsuro Hongo Megumi Nagano Chiho Watanabe Ryutaro Ohtsuka 《American journal of human biology》2005,17(6):696-703
Pacific Islands populations can be broadly divided into Austronesians (AN) and Non-Austronesians (NAN); obesity and type 2 diabetes are prevalent in the former, although leptin levels in both groups have seldom been investigated. Thirty-seven (20 male and 17 female) adult pairs, matched by age and percent body fat, from AN-speaking Balopa and NAN-speaking Huli, all of whom migrated to settle in Port Moresby, the capital of Papua New Guinea, were selected for comparison of their serum leptin concentrations. The Balopa did not differ significantly from the Huli in age (30.5 +/- 9.7 and 30.0 +/- 8.7 years for males, 33.7 +/- 8.9 and 34.1 +/- 7.5 years for females, respectively) or percent body fat (19.4 +/- 5.6 and 18.8 +/- 4.6 for males, 34.1 +/- 6.2 and 33.3 +/- 5.0 for females), although the BMI of females was lower in the Balopa (26.4 +/- 4.9) than in the Huli (29.7 +/- 4.7) (P = 0.02). In both ethnic groups, females had markedly higher leptin concentrations than males, but there was no significant inter-group difference in males (3.5 +/- 2.6 and 3.1 +/- 4.7 ng/ml, P = 0.14) or females (22.7 +/- 12.9 and 19.7 +/- 11.9 ng/ml, P = 0.40), after controlling for lifestyle factors and serum lipids. Multiple regression analysis revealed that significant predictors of leptin concentration were % body fat (beta = 0.58), sex (male, 0; female, 1; beta = 0.27), and smoker status (non-smoker, 0; smoker, 1; beta = -0.15) (R(2) = 0.80), implying that the leptin concentration was primarily determined by lifestyle-derived body fatness. In conclusion, the NAN populations do not endogenously differ in leptin status from the AN populations, who have been recognized as a typical group with a "thrifty" genotype. 相似文献
147.
Wakabayashi Y Watanabe H Inoue J Takeda N Sakata J Mishima Y Hitomi J Yamamoto T Utsuyama M Niwa O Aizawa S Kominami R 《Nature immunology》2003,4(6):533-539
The gene Bcl11b, which encodes zinc finger proteins, and its paralog, Bcl11a, are associated with immune-system malignancies. We have generated Bcl11b-deficient mice that show a block at the CD4-CD8- double-negative stage of thymocyte development without any impairment in cells of B- or gammadelta T cell lineages. The Bcl11b-/- thymocytes showed unsuccessful recombination of V(beta) to D(beta) and lacked the pre-T cell receptor (TCR) complex on the cell surface, owing to the absence of Tcrb mRNA expression. In addition, we saw profound apoptosis in the thymus of neonatal Bcl11b-/- mice. These results suggest that Bcl11b is a key regulator of both differentiation and survival during thymocyte development. 相似文献
148.
Okamoto E Watanabe K Hashiba K Inoue T Iwazawa E Momoi M Hashimoto T Mitamura Y 《ASAIO journal (American Society for Artificial Internal Organs : 1992)》2002,48(5):495-502
An implantable secondary battery is one of the key components in a total artificial heart system. Because a 2 year cycle life is required, the cycle life of the secondary battery as well as its charge and discharge properties are important parameters for selection of an appropriate battery. We carried out cycle life tests on four kinds of rechargeable batteries (a Ni-MH secondary battery, a Ni-Cd secondary battery, a Li-ion battery with a graphite anode, and a Li-ion battery with a nongraphitizable carbon electrode) to determine their suitability as implanted back-up batteries. Each of the batteries was charge/discharge cycled at 37 degrees C to 39 degrees C using a charge current of 1 C ampere, and they were each fully discharged under either pulsatile discharge loads, which mimicked pulsatile operation, or a nonpulsatile load equivalent to the average of the pulsatile loads. The two Li-ion batteries made by different manufacturers both met the minimum requirement of cycle life of more than 1,500 cycles, considering safety coefficient regardless of the discharge pattern. In addition, the temperature increase of these Li-ion batteries (3 degrees C) was lower than that of Ni-Cd and Ni-MH batteries (15-25 degrees C). Out of these four batteries, the two Li-ion batteries are the most suitable for use in a totally implantable artificial heart system. 相似文献
149.
150.
N Ida S Sakurai T Hosaka K Hosoi T Kunitomo Y Matsuura M Kohase 《Journal of immunological methods》1990,133(2):279-284
An enzyme-linked immunosorbent assay has been developed to measure human interleukin-6. The assay, based on the avidin-biotin amplified two-step sandwich method, is quick (requiring 4.5 h), sensitive (detecting 9.5 pg/ml) and satisfactory in reproducibility and specificity. It shows good correspondence with the results of bioassays, and it is not affected by serum and plasma components. These results indicate that this ELISA is suitable for application to clinical samples, which is a major advantage over the widely used bioassays. 相似文献