Maroni和Boaz公式评估慢性肾脏病患者蛋白质及磷摄入量

目的:探索Boaz公式是否可以真实反应中国慢性肾脏病(CKD) 3～5D期患者磷摄入量; Maroni公式是否能准确预测CKD 3～5期患者蛋白质摄入量。方法:于2016年3月～2017年6月于中国医科大学附属第一医院肾内科,运用CKD-EPI公式估算患者肾小球滤过率(e GFR)判断其肾功能,选取确诊CKD 3～5D期的住院患者110例。肾内科医师筛选符合入选及排除标准患者介绍给营养师进行营养宣教、膳食调查,比较患者蛋白质及磷实际摄入量与推荐及评估摄入量关系。结果:CKD 3～5期患者蛋白质实际摄入量符合推荐摄入量,但其均高于Maroni公式评估摄入量,且有统计学差异(P<0. 05); CKD 3～4期及CKD 5D期患者磷实际摄入量在标准范围内,CKD 5期低于推荐量,各期均与Boaz公式评估摄入量无统计学差异(P> 0. 05);结论:大部分CKD患者都能按指南推荐量合理控制饮食; Maroni公式可能不适用于评估我国CKD患者蛋白质摄入量,而Boaz公式适合评估磷摄入量。

日粮磷水平对泌乳奶牛生产性能及磷排放的影响

【目的】研究日粮磷水平对奶牛生产性能及磷排放量的影响,为中国奶牛饲养标准中磷需要量的制定提供数据参考。【方法】采用单因子试验设计,30头中国荷斯坦奶牛随机被分为3组,每组10头,分别饲喂干物质基础磷含量分别为0.32%、0.44%和0.56%的日粮,试验期75 d;其中,预试期15 d,正式期60 d,正式期最后5 d为采样期。【结果】磷的不同摄入量对采食量、生产性能及乳成分无显著影响(P>0.05),血清中钙、磷、碱性磷酸酶、羟脯氨酸以及唾液磷含量均处于正常值。0.32%磷日粮组每天通过粪尿向环境排磷量分别比0.44%和0.56%的磷日粮组少20.40 g(P<0.01)和45.84 g(P<0.01);其中,粪中水溶性磷排放量分别比0.44%和0.56%磷日粮组少15.24 g(P<0.01)和45.61 g(P<0.01),奶牛的饲养成本每天分别降低了0.60元/头和0.40元/头。【结论】日粮干物质基础磷水平为0.32%时对中国泌乳奶牛生产性能无不利影响,且显著降低粪磷含量,增加奶牛养殖的经济效益和生态效益。

慢性肾脏病患者饮食磷摄入现状及与钙磷代谢相关性研究

目的探讨慢性肾脏病患者饮食磷摄入情况,并分析饮食中磷摄入量对血营养指标及钙磷代谢相关指标的影响。方法以2018年12月至2019年11月成都市某医院诊治的慢性肾脏病患者为研究对象,进行基本资料收集、3 d 24 h膳食调查、营养状态评估及血生化指标检测,采用描述流行病学分析方法对慢性肾脏病患者饮食磷摄入量进行分析。结果共对151例慢性肾脏病患者进行研究,患者年龄25~75岁,以60~75岁为主,占64.9%,男女性别比为1.25∶1,疾病分期以3期为主,占49.0%,原发病以肾小球肾炎为主,占70.9%,主观营养评估(SGA)法评定结果以B级(可疑营养不良)为主,占86.1%。饮食磷摄入量以中等水平(600~800 mg/d)为主,占58.6%,其次是高水平(>800 mg/d),占23.6%,摄入量低水平(<600 mg/d)的占17.8%。不同饮食磷摄入量的慢性肾脏病患者白蛋白、前白蛋白、血磷、血磷钙乘积指标差异均有统计学意义(均P<0.01),转铁蛋白、血钙水平在不同饮食磷摄入量慢性肾脏病患者中的差异均无统计学意义(均P>0.05)。血磷及血钙磷乘积与饮食磷摄入量呈正相关(rs=0.736、0.809,均P<0.05)。结论饮食磷摄入量对慢性肾脏病患者的营养状况和磷代谢有一定影响,慢性肾脏病患者应注意按营养师的指导注意挑选钾含量较低的食物,在保证机体生理需求前提下,有效控制磷的摄入量,预防高磷血症的发生。

Nitrogen and phosphorus intake by phytoplankton in the Xiamen Bay

This paper describes a time series experiment examining the nitrogen and phosphorus intake of natural phytoplankton communities by a microcosms approach.Seawater samples containing natural phytoplankton communities were collected from waters around Baozhu Islet in inner Xiamen Bay and around Qingyu Islet in the outer bay.The goal was to elucidate the relationship between phytoplankton population enhancement,the biological removal of nitrogen and phosphorus from the seawater,and the phytoplankton nitrogen and phosphorus intake ratio based on nitrogen and phosphorus removal from seawater by phytoplankton,to provide a basis for detecting prewarning conditions for red tide and the assessment of red tide events.Two key results were obtained:1.During the experiment,the nitrogen and phosphorus seawater concentrations in samples from these two sites were negatively and closely correlated to the logarithm of the phytoplankton cell concentration and to the value of the apparent oxygen increment.The ratio of the intake coefficients was 3.5:1 for phosphorus and 1.1:1 for nitrogen for the phytoplankton between these samples from around Baozhu Islet and Qingyu Islet,respectively.This indicates that the intake capabilities of phytoplankton for nitrogen in the two waters are essentially identical.However,for phosphorus,the capability was much higher in the Baozhu Islet waters than the Qingyu Islet waters.In other words,the phytoplankton in Qingyu Islet waters produced more biomass while consuming the same amount of phosphorus as the other waters;2.The phytoplankton nitrogen and phosphorus intake ratio from the Baozhu Islet and Qingyu Islet waters was 20:1 and 36:1,respectively.The latter waters had a significantly higher ratio than the former and both were higher than the Redfield Ratio.These results indicate that nitrogen and phosphorus intake ratios by phytoplankton can vary significantly from region to region.