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排序方式: 共有2046条查询结果,搜索用时 15 毫秒
61.
Mase Kaori Saito Chie Usui Joichi Arimura Yoshihiro Nitta Kosaku Wada Takashi Makino Hirofumi Muso Eri Hirawa Nobuhito Kobayashi Masaki Yumura Wako Fujimoto Shouichi Nakagawa Naoki Ito Takafumi Yuzawa Yukio Matsuo Seiichi Yamagata Kunihiro 《Clinical and experimental nephrology》2022,26(11):1092-1099
Clinical and Experimental Nephrology - The life prognosis of elderly patients with myeloperoxidase–anti-neutrophil cytoplasmic antibodies-associated vasculitis (MPO-AAV) has been improved by... 相似文献
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Shin-ichiro Nitta Mari Hashimoto Yasuhiro Kazuki Shoko Takehara Hiraku Suzuki Mitsuo Oshimura Hidetaka Akita Kan Chiba Kaoru Kobayashi 《The AAPS journal》2018,20(3):61
Cytochrome P450 3A (CYP3A) enzymes metabolize approximately half of all drugs on the market. Since the endogenous compounds 4β-hydroxycholesterol (4β-HC) and 25-hydroxycholesterol (25-HC) are generated from cholesterol via CYP3A enzymes, we examined whether the plasma levels of 4β-HC and 25-HC reflect hepatic CYP3A4 activity by using a CYP3A-humanized mouse model, in which the function of endogenous Cyp3a was genetically replaced by human CYP3A. CYP3A-humanized mice have great advantages for evaluation of the relationship between hepatic CYP3A protein levels and plasma and hepatic levels of 4β-HC and 25-HC. Levels of CYP3A4 protein in the liver microsomes of CYP3A-humanized mice were increased by treatment with pregnenolone-16α-carbonitrile, a CYP3A inducer. Hepatic and plasma levels of 4β-HC and 25-HC normalized by cholesterol were significantly correlated with hepatic CYP3A4 protein levels. In addition, in vitro studies using human liver microsomes showed that the formation of 4β-HC was strongly inhibited by a CYP3A inhibitor, while the inhibitory effect of the CYP3A inhibition on the formation of 25-HC was weak. These results suggested that CYP3A mainly contributed to the formation of 4β-HC in human liver microsomes, whereas other factors may be involved in the formation of 25-HC. In conclusion, the in vivo studies using CYP3A-humanized mice suggest that plasma 4β-HC and 25-HC levels reflect hepatic CYP3A4 activity. Furthermore, taking the results of in vitro studies using human liver microsomes into consideration, 4β-HC is a more reliable biomarker of hepatic CYP3A activity. 相似文献
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Teruhiko Imamura Nikhil Narang Daisuke Nitta Takeo Fujino Ann Nguyen Gene Kim Jayant Raikhelkar Daniel Rodgers Takeyoshi Ota Valluvan Jeevanandam Gabriel Sayer Nir Uriel 《Artificial organs》2020,44(12):e509-e519
Cannula position in HeartMate II and HeartWare left ventricular assist devices (LVADs) is associated with clinical outcome. This study aimed to investigate the clinical implication of the device positioning in HeartMate 3 LVAD cohort. Consecutive patients who underwent HeartMate 3 LVAD implantation were followed for one year from index discharge. At index discharge, chest X-ray parameters were measured: (a) cannula coronal angle, (b) height of pump bottom, (c) cannula sagittal angle, and (d) cannula lumen area. The association of each measurement of cannula position with one-year clinical outcomes was investigated. Sixty-four HeartMate 3 LVAD patients (58 years old, 64% male) were enrolled. In the multivariable Cox regression model, the cannula coronal angle was a significant predictor of death or heart failure readmission (hazard ratio 1.27 [1.01-1.60], P = .045). Patients with a cannula coronal angle ≤28° had lower central venous pressure (P = .030), lower pulmonary capillary wedge pressure (P = .027), and smaller left ventricular size (P = .019) compared to those with the angle >28°. Right ventricular size and parameters of right ventricular function were also better in the narrow angle group, as was one-year cumulative incidence of death or heart failure readmission (10% vs. 50%, P = .008). Narrow cannula coronal angle in patients with HeartMate 3 LVADs was associated with improved cardiac unloading and lower incidence of death or heart failure readmission. Larger studies to confirm the implication of optimal device positioning are warranted. 相似文献
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A quantitative 1H-NMR method (qHNMR) was used to measure the amygdalin content of Persicae semen, Armeniacae semen, and Mume fructus, in each of which amygdalin constitutes a major component. The purity of amygdalin was calculated from the ratio of the intensity of the amygdalin H-2 signal at δ 6.50 ppm in pyridine-d 5 to that of the hexamethyldisilane (HMD) signal at 0 ppm. The HMD concentration was corrected by the International System of Units (SI) traceability with certified reference material (CRM)-grade bisphenol A. qHNMR revealed the amygdalin contents to be 2.72 and 3.13 % in 2 lots of Persicae semen, 3.62 and 5.19 % in 2 lots of Armeniacae semen, and 0.23 % in Mume fructus. Thus, we demonstrated the utility of this method for the quantitative analysis of crude drugs. 相似文献
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J.K. Friedman C.H. Nitta K.M. Henderson S.J. Codianni L. Sanchez J.M. Ramiro-Diaz T.A. Howard W. Giermakowska N.L. Kanagy L.V. Gonzalez Bosc 《Vascular pharmacology》2014,60(1):17-24
Sleep apnea (SA), defined as intermittent respiratory arrest during sleep, is associated with increased incidence of hypertension, peripheral vascular disease, stroke, and sudden cardiac death. We have shown that intermittent hypoxia with CO2 supplementation (IH), a model for SA, increases blood pressure and circulating ET-1 levels, upregulates lung pre-pro ET-1 mRNA, increases vasoconstrictor reactivity to ET-1 in rat small mesenteric arteries (MA) and increases vascular reactive oxygen species (ROS). NFAT activity is increased in the aorta (AO) and MA of mice exposed to IH in an ET-1-dependent manner, and the genetic ablation of the isoform NFATc3 prevents IH-induced hypertension. We hypothesized that IH causes an increase in arterial ROS generation, which activates NFATc3 to increase vasoconstrictor reactivity to ET-1. In support of our hypothesis, we found that IH increases ROS in AO and MA. In vivo administration of the SOD mimetic tempol during IH exposure prevents IH-induced increases in NFAT activity in mouse MA and AO. We found that IH causes an NFATc3-dependent increase in vasoconstrictor reactivity to ET-1, accompanied by an increase in vessel wall [Ca2+]. Our results indicate that IH exposure causes an increase in arterial ROS to activate NFATc3, which then increases vasoconstrictor reactivity and Ca2+ response to ET-1. These studies highlight a novel regulatory pathway, and demonstrate the potential clinical relevance of NFAT inhibition to prevent hypertension in SA patients. 相似文献
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Naoki Yanagisawa Takashi Muramatsu Yasuyuki Yamamoto Ken Tsuchiya Kosaku Nitta Atsushi Ajisawa Katsuyuki Fukutake Minoru Ando 《Clinical and experimental nephrology》2014,18(4):600-605