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61.
Kimura T Sonoda Y Iwai N Satoh M Yamaguchi-Tsukio M Izui T Suda M Sasaki K Nakano T 《Experimental hematology》2000,28(6):635-641
Erythropoietin (EPO) is the principal regulator for the production of adult-type definitive erythrocytes (EryD). EPO not only stimulates both the proliferation and differentiation of EryD progenitors, but also maintains the viability of EryD progenitors. Compared to the abundant knowledge about the function of EPO in EryD production, the roles of EPO in the production of embryonic-type primitive erythrocytes (EryP) are less clear.The effects of EPO on EryP proliferation and differentiation were investigated using EryP purified from developing mouse embryos and the cells obtained from mouse embryonic stem cells using an in vitro differentiation induction.Immature EryP of both in vivo and in vitro origin responded to EPO stimulation and underwent apoptosis with EPO deprivation. In contrast, there were no significant differences between the cultures with and without EPO, when fully mature EryP were examined, that is, EryP lost its dependency on EPO stimulation with maturation.These results show that EPO functions as a survival factor for immature embryonic EryP as well as immature EryD progenitors. 相似文献
62.
Nakaichi Tetsu Yamashita Shozo Kawakami Wataru Yamamoto Haruki Sasaki Masayuki Yokoyama Kunihiko 《Annals of nuclear medicine》2020,34(8):583-594
Annals of Nuclear Medicine - This study aimed to evaluate the accuracy of six threshold-based segmentation methods with different target-to-background ratios (TBR), images with different voxel... 相似文献
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Plasma lipids and osteoporosis in postmenopausal women 总被引:18,自引:0,他引:18
Yamaguchi T Sugimoto T Yano S Yamauchi M Sowa H Chen Q Chihara K 《Endocrine journal》2002,49(2):211-217
Many clinical studies have shown that osteoporosis is associated with atherosclerosis and cardiovascular death. Although both high plasma levels of low density lipoprotein cholesterol (LDL-C) and low plasma levels of high density lipoprotein cholesterol (HDL-C) are known to be risk factors for atherosclerosis, it is unclear whether such lipid derangements are also associated with the pathogenesis of osteoporosis. In this study, we evaluated the relationships between plasma levels of total C, LDL-C, HDL-C, or triglyceride (TG) versus bone mineral density (BMD) at the lumbar spine, femoral neck, radius, or total body as well as the presence of vertebral fractures in 214 Japanese postmenopausal women (age range, 47-86 years, mean 62.7). Multiple regression analysis was performed between BMD at each skeletal site versus each lipid level adjusted for age, years after menopause, body mass index (BMI), and %fat. Plasma LDL-C levels were significantly and inversely correlated with the absolute values of both one-third radial (1/3R) and distal radial (UDR) BMD (p<0.01), and tended to be inversely correlated with the absolute values of L-BMD (p=0.051). In contrast, plasma HDL-C levels were significantly and positively correlated with the absolute values of L, 1/3R and UDR BMD (p<0.05). On the other hand, plasma TG levels were significantly lower in women with vertebral fractures than in those without fractures (97.0+/-36.5 vs. 126.4+/-65.8 mg/dl, mean+/-SD, p<0.05). When multivariate logistic regression analysis was performed with the presence of vertebral fractures as a dependent variable and each lipid level adjusted for age, years after menopause, BMI, and %fat as independent variables, TG alone was selected as an index affecting the presence of vertebral fractures (odds ratio: 0.51, 95% confidential interval: 0.29-0.89 per SD increase, p<0.05). Our study showed that plasma LDL-C and HDL-C levels were inversely and positively correlated with both R- and L-BMD values, respectively, while low plasma TG levels were associated with the presence of vertebral fractures in postmenopausal women. Thus, plasma lipids might be related to bone mass and bone fragility, and might be the common factor underlying both osteoporosis and atherosclerosis. 相似文献
66.
Miwako Takeda Takafumi Abe Yuta Toyama Kazumichi Tominaga Shozo Yano Toru Nabika Masayuki Yamasaki 《Journal of Rural Medicine》2022,17(2):67
Objective: Although oral health and skeletal muscle status are known to be risk factors for type 2 diabetes mellitus (T2DM), there is limited information on their combined effects among community-dwelling older adults. The purpose of this study was to investigate the association between oral health and skeletal muscle status among older adults with T2DM in Japan.Participants and Methods: This cross-sectional study included data from individuals aged ≥60 years. T2DM was defined as a glycosylated hemoglobin A1c level ≥48 mmol/mol (≥6.5%) or the use of hypoglycemic agents. For oral health status, dental hygienists assessed the number of teeth (NT) and masticatory function (MF). Skeletal muscle status was assessed using skeletal muscle mass index (SMI) and handgrip strength (HGS). Logistic regression analysis examined T2DM in nine-category combinations of oral health status (each of the three categories in NT and MF) and skeletal status (each of the three categories in SMI and HGS).Results: T2DM was prevalent in 83 participants (16.4%) and was significantly associated with low NT and SMI (odds ratio [OR] = 5.93, 95% confidence interval [CI]: 1.37–25.73) and low MF and SMI (OR = 4.48, 95% CI: 1.23–16.35) compared to high NT and SMI and high MF and SMI, respectively.Conclusion: Our findings indicate that low muscle mass with tooth loss or masticatory dysfunction is associated with T2DM among community-dwelling older adults. This suggests that maintaining oral health and muscle mass may be an effective strategy for the prevention of T2DM. 相似文献
67.
Hideaki Miyamoto Hiroaki Ikematsu Satoshi Fujii Shozo Osera Tomoyuki Odagaki Yasuhiro Oono Tomonori Yano Atsushi Ochiai Yutaka Sasaki Kazuhiro Kaneko 《International journal of colorectal disease》2014,29(9):1069-1075
Purpose
Laterally spreading tumors (LST) have been recognized worldwide. The aim of our retrospective study was to evaluate the clinicopathological differences of LST arising in the colon and rectum.Methods
We investigated the clinical records of consecutive patients with LST that were endoscopically or surgically resected at our hospital between February 2006 and March 2011. LST were classified into three types: granular-homogenous (LST-GH), granular-nodular mixed (LST-GM), and nongranular (LST-NG) types. We also defined the hardly elevated flat lesion with a dilated pit pattern that occurs at the margins of LST as the “skirt.” The clinicopathological characteristics of the LST arising in the colon and rectum, including the presence of the skirt, were compared.Results
A total of 496 colorectal LST in 435 patients were examined. LST-GM was predominant in the rectum, whereas LST-NG was predominant in the colon (p?0.001). The mean tumor size was larger in the rectum (39.3?±?17.9 mm) than the colon (25.8?±?13.6 mm) (p?0.001). Low-grade dysplasia frequency was lower in the rectum than the colon (4 vs. 37 %, p?0.001). The skirt was identified in 15 lesions (3.0 %), with a higher incidence in the rectum than the colon (17 vs. 0.5 %, p?0.001). The skirt was found only in LST-GM.Conclusions
A greater proportion of LST-GM, greater mean size, and lower incidence of low-grade dysplasia were found in rectal LST. The skirt was a novel and unique finding, primarily observed in rectal LST-GM cases. 相似文献68.
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