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991.

Background

We sought to develop a new equation to estimate glomerular filtration rate (GFR) in Chinese elderly population.

Methods

A total of 668 Chinese elderly participants, including the development cohort (n = 433), the validation cohort (n = 235) were enrolled. The new equation using the generalized additive model, and age, gender, serum creatinine as predictor variables was developed and the performances was compared with the CKD-EPI equation.

Results

In the validation data set, both bias and precision were improved with the new equation, as compared with the CKD-EPI equation (median difference, −1.5 ml/min/1.73 m2 vs. 7.4 ml/min/1.73 m2 for the new equation and the CKD-EPI equation, [P<0.001]; interquartile range [IQR] for the difference, 16.2 ml/min/1.73 m2 vs. 19.0 ml/min/1.73 m2 [P<0.001]), as were accuracies (15% accuracy, 40.4% vs. 30.6% [P = 0.02]; 30% accuracy, 71.1% vs. 47.2%, [P<0.001]; 50% accuracy, 90.2% vs. 75.7%, [P<0.001]), allowing improvement in GFR categorization (GFR category misclassification rate, 37.4% vs. 53.2% [P = <0.001]).

Conclusions

A new equation was developed in Chinese elderly population. In the validation data set, the new equation performed better than the original CKD-EPI equation. The new equation needs further external validations. Calibration of the GFR referent standard to a more accurate one should be an useful way to improve the performance of GFR estimating equations.  相似文献   
992.
Photosynthesis Research - Non-photochemical quenching (NPQ) in photosynthetic organisms provides the necessary photoprotection that allows them to cope with largely and quickly varying light...  相似文献   
993.
Chen  Chun-Yen  Lin  Pei-Hsuan  Chen  Kun-Hung  Cheng  Yi-Sheng 《Plant molecular biology》2020,104(4-5):483-498
Plant Molecular Biology - The phytohormone ethylene is widely involved in many developmental processes and is a crucial regulator of defense responses against biotic and abiotic stresses in plants....  相似文献   
994.

Leaf senescence, which affects plant growth and yield in rice, is an ideal target for crop improvement and remarkable advances have been made to identify the mechanism underlying this process. We have characterized an early senile mutant es5 (early leaf senescence 5) in rice exhibiting leaf yellowing phenotype after the 4-leaf stage. This phenotype was confirmed by the higher accumulation of reactive oxygen species (ROS) and malondialdehyde (MDA), the disintegration of chloroplasts, reduction in chlorophyll content and photosynthetic rate and up-regulation of senescence-associated genes (SAGs) like Osh36, OsI57, and OsI85. Positional cloning revealed that the es5 phenotype is the result of one base substitution in ES5, encoding phosphatidylserine synthase (PSS) family protein, which is involved in the base-exchange type reaction to synthesize the minor membrane phospholipid phosphatidylserine. Functional complementation of ES5 in the es5 plants completely restored the wild-type phenotype. Ultra-high-performance liquid chromatography (UHPLC) analysis showed that es5 plants had increased levels of phosphatidylserine (PS) and decreased level of phosphatidylcholine (PC). These results provide evidence about the role of PS in rice leaf senescence.

  相似文献   
995.
微生物作为生物群体的重要组成成员,其生长受外界物化条件(如温度、盐度、pH等)影响较大。温泉作为极端水生环境之一,属于相对稳定且较为特殊的生态系统,使生长于其中的微生物可能具有适应高温等特殊生境的独特生存生理机制,具体表现为微生物物种及其活性次级代谢产物呈现出一定的多样性与新颖性。本文从菌株物种多样性分析及其酶活性研究方面,综述了近5年来国内温泉微生物相关研究进展,以期为温泉等极端环境微生物资源开发与保护提供参考。  相似文献   
996.
Yang  Meifang  Wei  Ming  Wang  Chengjian  Lu  Yu  Jin  Wanjun  Gao  Xi  Li  Cheng  Wang  Langhong  Huang  Linjuan  Wang  Zhongfu 《Glycoconjugate journal》2020,37(2):165-174
Glycoconjugate Journal - The study of carbohydrates requires large amounts of glycans. N-Glycans can be synthesized but generating large quantities of N-glycans with diverse structures remains...  相似文献   
997.
998.
Sexual patterns of teleosts are extremely diverse and include both gonochorism and hermaphroditism. As a protogynous hermaphroditic fish, all orange-spotted groupers (Epinephelus coioides) develop directly into females, and some individuals change sex to become functional males later in life. This study investigated gonadal restructuring, shifts in sex hormone levels and gene profiles of cultured mature female groupers during the first (main) breeding season of 2019 in Huizhou, China (22° 42′ 02.6″ N, 114° 32′ 10.1″ E). Analysis of gonadal restructuring revealed that females with pre-vitellogenic ovaries underwent vitellogenesis, spawning and regression and then returned to the pre-vitellogenic stage in the late breeding season, at which point some changed sex to become males via the intersex gonad stage. A significant decrease in the level of serum 17β-estradiol (E2) was observed during ovary regression but not during sex change, whereas serum 11-ketotestosterone (11-KT) concentrations increased significantly during sex change with the highest concentration in newly developed males. Consistent with serum hormone changes, a significant decrease in cyp19a1a expression was observed during ovary regression but not during sex change, whereas the expression of cyp11c1 and hsd11b2 increased significantly during sex change. Interestingly, hsd11b2 but not cyp11c1 was significantly upregulated from the pre-vitellogenic ovary stage to the early intersex gonad stage. These results suggest that a decrease in serum E2 concentration and downregulation of cyp19a1a expression are not necessary to trigger the female-to-male transformation, whereas increased 11-KT concentration and upregulation of hsd11b2 expression may be key events for the initiation of sex change in the orange-spotted grouper.  相似文献   
999.
Cheng  Yikang  Zhang  Hui  Zang  Runguo  Wang  Xixi  Long  Wenxing  Wang  Xu  Xiong  Menghui  John  Robert 《Plant and Soil》2020,449(1-2):51-63
Plant and Soil - Soil phosphorus is a key driver of plant biodiversity and aboveground biomass (AGB) in tropical forests. A plant community’s ability to exploit such limiting resources may be...  相似文献   
1000.
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