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Trace element concentrations in body tissues of healthy centenarians have not been widely analyzed, yet they can be used as
reference data leading to improved assessment of the aging process and monitoring of the micronutrient status of this age
group. The present study sought to assess trace element concentrations and behaviors in the fingernails of healthy Chinese
centenarians. The effects of gender on element concentrations, which also play an important role in determining the lifespan,
were also investigated. Trace elements (Ba, Cd, Co, Cr, Cu, Fe, Li, Mn, Mo, Ni, Pb, Se, Sr, and Zn) in the fingernails of
78 healthy Chinese centenarians were determined by inductively coupled plasma mass spectrometry. The overall reference values
obtained in milligram per kilogram are as follows: Ba, 5.10; Cd, 0.031; Co, 0.101; Cr, 0.82; Cu, 3.71; Fe, 154.35; Li, 0.31;
Mn, 3.09; Mo, 0.040; Ni, 0.95; Pb, 1.86; Se, 0.44; Sr, 6.20; and Zn, 147.96. Data analysis showed that only Cr and Se concentrations
show a normal distribution, and no significant difference between male and female groups was found for any element except
Cr. Result also revealed that sufficient Se, Co, and Zn as well as lower or lack of exposure to Cr contribute positively to
the lifespan of centenarians. The results suggest that regulating in vivo contents of trace elements, especially Se, Co, and
Zn, is reasonable to intervene with geriatric diseases. 相似文献
65.
L. W. Zhu P. Zhao X. A. Cai X. P. Zeng G. Y. Ni J. Y. Zhang L. L. Zou T. T. Mei M. H. Yu 《Trees - Structure and Function》2012,26(2):535-542
Stem CO2 efflux (E
s) has been estimated from a temperature-related equation, but sap flux often affects measurements of E
s, which leads to misunderstanding real stem respiration. In order to observe the relationship between E
s and stem temperature and to analyze the effect of sap velocity on E
s, stem temperature, E
s and sap flux were measured from a subtropical Schima superba plantation in South China on three trees for consecutive 3 days in July and October 2009. Stem temperature, E
s and sap velocity were significantly higher in July than in October. Stem temperature could explain 17–41 and 54–75% variations
of E
s in July and October, respectively. A negative relationship between E
s and stem temperature was found during 1800–2300 hours in July. The daytime E
s was 9.2, 4.3 and 2.4% higher than the predicted for three trees in July, and this occurred only on Tree 1 in October. Sap
velocity was positively correlated with E
s for three trees in July, and the increase of E
s with the increase of sap velocity was only observed on Tree 1 in October. These results demonstrated that the occurrence
of sap flux could account for the increase of daytime E
s, and the effect of sap velocity on E
s varied with the seasons from the S. superba stem. 相似文献
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ObjectiveClient adherence is vital for effective methadone maintenance treatment (MMT). This study explores the pattern and associated factors of client adherence, drop-out and re-enrolment in the Chinese MMT programme over the period of 2006–2013.MethodsThis retrospective study was conducted in 14 MMT clinics in Guangdong Province, China. We employed Kaplan-Meier survival analysis to estimate the rates of drop-out and re-enrolment of MMT clients and multivariate Cox regression to identify associated factors.ResultsAmong 1,512 study participants, 79% have experienced ‘drop-out’ during the 7-year study period. However, 82% ‘dropped-out’ clients resumed treatment at a later time. Low education level (junior high or below versus otherwise, HR = 1.21, 1.05–1.40), low methadone dosage in the first treatment episode (<50 ml versus ≥50 ml, HR = 1.84, 1.64–2.06) and higher proportion of positive urine test (≥50% versus<50%, HR = 3.72, 3.30–4.20) during the first treatment episode were strong predictors of subsequent drop-outs of the participants. Among the ‘dropped-out’ clients, being female (HR = 1.40, 1.23–1.60), being married (HR = 1.19, 1.09–1.30), and having a higher proportion of positive urine tests in the first treatment episode (≥50% versus<50%, HR = 1.35, 1.20–1.51) had greater likelihood of subsequent re-enrolment in MMT. Clients receiving lower methadone dosage (first treatment episode <50 ml versus ≥50 ml, HR = 1.12, 1.03–1.23; the last intake before drop-out <50 ml versus ≥50 ml, HR = 1.16, 1.04–1.30) were also more likely to re-enrol.ConclusionPersistent cycling in-and-out of clients in MMT programmes is common. Insufficient dosage and higher proportion of positive urine samples in the first treatment episode are the key determinants for subsequent client drop-out and re-enrolment. Interventions should target clients in their early stage of treatment to improve retention in the long term. 相似文献
67.
Zou Ya-Jie Wang He-Xiang Zhang Jin-Xia 《International journal of peptide research and therapeutics》2019,25(4):1389-1396
International Journal of Peptide Research and Therapeutics - A novel peroxidase has been isolated from fresh fruiting bodies of the mushroom Pleurotus pulmonarius, with a purification protocol of... 相似文献
68.
Longhua Liu Louise D. Zheng Peng Zou Joseph Brooke Cayleen Smith Yun Chau Long 《Cell cycle (Georgetown, Tex.)》2016,15(15):2033-2041
Obesity and related metabolic disorders constitute one of the most pressing heath concerns worldwide. Increased adiposity is linked to autophagy upregulation in adipose tissues. However, it is unknown how autophagy is upregulated and contributes to aberrant adiposity. Here we show a FoxO1-autophagy-FSP27 axis that regulates adipogenesis and lipid droplet (LD) growth in adipocytes. Adipocyte differentiation was associated with upregulation of autophagy and fat specific protein 27 (FSP27), a key regulator of adipocyte maturation and expansion by promoting LD formation and growth. However, FoxO1 specific inhibitor AS1842856 potently suppressed autophagy, FSP27 expression, and adipocyte differentiation. In terminally differentiated adipocytes, AS1842856 significantly reduced FSP27 level and LD size, which was recapitulated by autophagy inhibitors (bafilomycin-A1 and leupeptin, BL). Similarly, AS1842856 and BL dampened autophagy activity and FSP27 expression in explant cultures of white adipose tissue. To our knowledge, this is the first study addressing FoxO1 in the regulation of adipose autophagy, shedding light on the mechanism of increased autophagy and adiposity in obese individuals. Given that adipogenesis and adipocyte expansion contribute to aberrant adiposity, targeting the FoxO1-autophagy-FSP27 axis may lead to new anti-obesity options. 相似文献
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表没食子儿茶素没食子酸酯研究进展 总被引:15,自引:2,他引:15
近些年发现,茶叶中的表没食子儿茶素没食子酸脂具有降低血脂、除去胆固醇、抑制细菌和病毒、抗氧化、抗突变、抗肿瘤等多方面的重要生理功能。 相似文献