Longitudinal changes in body weight of breastfeeding mothers in the first year after delivery and its relationship with human milk composition:a combined longitudinal and cross-sectional cohort study

Objective:Postpartum weight retention(PPWR)is a common problem among women after childbirth.The main objectives of this study are to understand the changes in body weight of breastfeeding mothers during long-term follow-up and preliminarily explore the relationship between maternal body weight and human milk composition,including macronutrients,leptin,and adiponectin.Methods:The study included a longitudinal cohort(122 mothers),and a cross-sectional cohort(37 mothers).The human milk,maternal weight,and dietary surveys were collected in the longitudinal cohort at different follow-up time points(1-14 days postpartum,2-4 months postpartum,5-7 months postpartum,and 12-17 months postpartum).The maternal body weight was analyzed using the responses in the survey questionnaires.A milk analyzer based on the mid-infrared spectroscopy(MIRS)was used to determine milk composition,and nutrition analysis software evaluated dietary intakes.In the cross-sectional cohort,participating mothers were asked to provide blood and human milk samples and pertinent information related to maternal body composition.Maternal body composition was measured by bioelectrical impedance analysis(BIA),while ELISA analyzed leptin and adiponectin in milk and serum.Results:At 5-7 months postpartum,the PPWR of breastfeeding mothers was(2.46±3.59)kg.At 12-17 months postpartum,the PPWR was(0.98±4.06)kg.PPWR was found to be negatively correlated with milk fat content within 14 days postpartum and positively correlated at 2-4 months postpartum.In addition,the maternal weight and body muscle mass were positively correlated with leptin and adiponectin in milk.Plasma leptin was positively correlated with the mother’s body weight,body mass index(BMI),FAT percentage,and body fat mass,while plasma adiponectin did not correlate with any parameter.The results also indicate that the PPWR did not correlate with leptin and adiponectin in plasma or milk.Conclusions:Breastfeeding mothers may retain considerable weight gain one year after delivery.Human milk composition may be related to changes in maternal body weight.Leptin and adiponectin in breast milk and leptin in plasma are associated with the maternal body composition.This study supports the notion that maternal nutritional status may affect offspring health through lactation,and future research should focus on exploring weight management of postpartum mothers.

The levels of osteopontin in human milk of Chinese mothers and its associations with maternal body composition

Objective:This study explored the content and change trend of osteopontin(OPN)in breast milk and analyzed the relationship between OPN in breast milk and maternal body composition.Methods:Breast-feeding mothers were recruited in Xinhua Hospital to collect breast milk and provide pertinent information.The content of OPN in breast milk was determined by enzyme-linked immunosorbent assay(ELISA).Determination of protein content in human milk was performed via the BCA method.The maternal body composition was determined by the bioelectrical impedance method.Serum glucocorticoid receptorα,adiponectin,insulin,and leptin were determined by ELISA.SPSS 25 was used for statistical analysis.Results:In the longitudinal cohort,106 mothers provided 318 milk samples at different lactation periods.The results indicate that the OPN showed dynamic changes.OPN levels were(343.2±163.5)mg/L during 1-14 days postpartum,(228.4±121.5)mg/L during 2-4 months postpartum,and(204.8±100.6)mg/L during 5-7 months postpartum.The content of OPN was very high in the first 1-14 days postpartum and then decreased.Compared with early postpartum milk,the OPN content of mature milk showed a significant relationship with maternal weight-related parameters.Additional body composition analysis was performed in 88 women at the mature milk phase.The results show that the OPN in milk is related to the mother’s body composition,especially the content of skeletal muscle mass,but not to relevant humoral factors.Conclusions:The levels of OPN in human milk of Chinese mothers showed dynamic changes with the extension of lactation time.The OPN in human milk was related to the mother’s body composition but not related to related humoral factors.

High level of deoxycholic acid in human bile does not promote cholesterol gallstone formation

AIM:To study whether patients with excess deoxycholic acid (DCA) differ from those with normal percentage of DCA with respect to biliary lipid composition and cholesterol saturation of gallbladder bile. METHODS:Bile was collected during operation through puncturing into the gallbladder from 122 cholesterol gallstone patients and 46 gallstone-free subjects undergoing cholecystectomy.Clinical data,biliary lipids,bile add composition, presence of crystals and nucleation time were analyzed. RESULTS:A subgroup of gallstone patients displayed a higher proportion of DCA in bile than gallstone free subjects. By choosing a cut-off level of the 90th percentile,a group of 13 gallstone patients with high DCA levels (mean 50 percent of total bile acids) and a large group of 109 patients with normal DCA levels (mean 21 percent of total bile acids) were obtained.The mean age of the patients with high DCA levels was higher than that of the group with normal levels (mean age:62 years vs45 years) and so was the mean BMI (28.3 vs.24.7).Plasma levels of cholesterol and triglycerides were slightly higher in the DCA excess groups compared with those in the normal DCA group.There was no difference in biliary lipid composition,cholesterol saturation,nucleation time or occurrence of cholesterol crystals in bile between patients with high and normal levels of DCA. CONCLUSION:Gallstone patients with excess DCA were of older age and had higher BMI than patients with normal DCA.The two groups of patients did not differ with respect to biliary lipid composition,cholesterol saturation,nucleation time or occurrence of cholesterol crystals.It is concluded that DCA in bile does not seem to contribute to gallstone formation in cholesterol gallstone patients.

人胎盘谷胱甘肽S-转移酶的纯化和性质

将人胎盘组织粗匀浆经105000×g超速离心后,用S-已基谷胱甘肽-琼脂糖-6B亲和层析一步纯化法获得电泳纯的人胎盘GST(简称GST-π)。其比活性较粗匀浆高194.7倍,回收率为50％。再经DE_(52)交换柱进一步纯化,用KCl浓度梯度洗脱后为单一锐峰,等电聚集电泳呈一条带,等电点(pI)为4.60。GST-π经TSKgel-G3000SW柱高效液相层析,也为单一对称锐峰,测得其分子量为45.2kD;在SDS-PAGE电泳也为单一区带,测得其亚基单位的分子量为22.5kD。GST-π氨基酸组成分析可检出十六种氨基酸,其中以谷氨酸、亮氨酸、丙氨酸、天冬氨酸及甘氨酸含量较高。 GST-π酶动力学研究证明GST-π以GST和CDNB为底物时km值分别为0.16mmol/L和0.55mmol/L,经测定表明,GST-π的最适作用pH值为7.5,在pH6.5—9的范围内较为稳定,体外GST-π在温度超过25℃对容易失活。以GST-π为抗原,得到兔抗人GST-π抗血清,其效价为1:32,与人肝GSTs不发生免疫交叉反应。

Impact of enteral nutrition on energy metabolism in patients with Crohn's disease

AIM: To investigate the impact of enteral nutrition(EN) on the body composition and metabolism in patientswith Crohn's disease(CD). METHODS: Sixty-one patients diagnosed with CD were enrolled in this study. They were given only EN(enteral nutritional suspension, TPF, non-elemental diet) support for 4 wk, without any treatment with corticosteroids, immunosuppressive drugs, infliximab or by surgical operation. Body composition statistics such as weight, body mass index, skeletal muscle mass(SMM), fat mass, protein mass and inflammation indexes such as C-reactive protein(CRP), erythrocyte sedimentation rate(ESR) and CD activity index(CDAI) were recorded before and after EN support. RESULTS: The 61 patients were divided into three groups according to CDAI before and after EN support: A(active phase into remission via EN, n = 21), B(remained in active phase before and after EN, n = 19) and C(in remission before and after EN, n = 21). Patients in group A had a significant increase in SMM(22.11 ± 4.77 kg vs 23.23 ± 4.49 kg, P = 0.044), protein mass(8.01 ± 1.57 kg vs 8.44 ± 1.45 kg, P = 0.019) and decrease in resting energy expenditure(REE) per kilogram(27.42 ± 5.01 kcal/kg per day vs 22.62 ± 5.45 kcal/kg per day, P < 0.05). There was no significant difference between predicted and measured REE in active CD patients according to the HarrisBenedict equation. There was no linear correlation between the measured REE and CRP, ESR or CDAI in active CD patients. CONCLUSION: EN could decrease the hypermetabolism in active CD patients by reducing the inflammatory response.

基于SVM的9电极人体成分分析模型

为提高体成分模型的精度,提出了一种基于支持向量机(Support Vector Machine,SVM)的9电极人体成分分析模型。在8电极测量模型的基础上,在腹部增加一个电极,利用9个测量电极以提高测量数据的准确性。采用SVM方法对受试人群数据进行分组,针对各个分组建立体成分分析模型。人体实验结果表明,所提模型的测量结果更加准确,且对模型经验参数不敏感。

Effect of insulin on hyperkalemia during anhepatic stage of liver transplantation

AIM:To investigate the effectiveness of insulin on decreasing serum potassium concentration during anhepatic stage of orthotopic liver transplantation. METHODS:Sixteen patients with serum potassium concentrations greater than 4.0 mmol/L at the onset of anhepatic stage were randomized into two groups.The patients in control group (n=8) received no treatment, while those in treatment group (n=8) received an intravenous bolus injection of regular insulin (20U) 10 min into the anhepatic stage,followed by a glucose infusion (500mL 50g/L dextrose) over 15 min. RESULTS:In control group,potassium concentration underwent no changes whereas in treatment group,it decreased from 4.8±0.48 mmol/L to 4.19±0.55 mmol/L (mean±SD) within 15 min and to 3.62±0.45 mmol/L 60 min after the therapy.The potassium concentration was lower in treatment group than in control group within 30 min of treatment (3.94±0.57 vs 4.47±0.42 mmol/L, respectively;P<0.05),and increased similarly 30 s after graft reperfusion in both groups of patients,but remained lower in treatment group (5.81±2.78 vs 7.44±1.75 mmol/L, respectively;P<0.05).The potassium concentration returned to pre-reperfusion levels within 5 min after graft reperfusion. CONCLUSION:In patients undergoing orthotopic liver transplantation,the administration of insulin rapidly decreases serum potassium concentration even in the absence of the liver,suggesting an important contribution by extrahepatic tissues in insulin-stimulated uptake of potassium.

不同骨量老年男性血清vaspin水平变化及意义

目的观察不同骨量老年男性血清内脏脂肪特异性丝氨酸酶抑制剂(vaspin)水平变化,并探讨其意义。方法选择在日照市人民医院健康查体的60~80岁的老年男性210例为研究对象,根据骨密度(BMD)将其分为正常组、骨量减少组、骨质疏松组。收集其基础资料(年龄、身高、体质量),测定血清学指标[血清Ca、血清P、血脂(TG、TC、LDL、HDL)、空腹葡萄糖(Glu)]及骨代谢五项,后者包括甲状腺旁腺素(PTH)、25羟维生素D[25(OH)D]、骨钙素(OC)、血清1型胶原C末端肽(CTX)、1型胶原N端前肽(P1NP);应用ELISA试剂盒检测血清vaspin水平;应用双能X线骨密度仪(DXA)检测股骨颈(FN)和腰椎(LS)两个部位的BMD;应用生物电阻抗法(BIA)测定人体成分组成,计算骨骼肌指数(SMI)。采用Spearman相关分析不同骨量老年男性血清vaspin水平与上述各指标的关系。将单因素分析中有统计学意义的因素纳入多因素logistic回归,分析其与老年男性骨质疏松症的关系。结果骨量减少组及骨质疏松组血清vaspin水平显著低于正常组,其中以骨质疏松组水平最低(P均<0.05)。在老年男性骨质疏松组,血清vaspin水平与HDL、P1NP、FNBMD及SMI呈正相关(r=0.676,P=0.007;r=0.548,P=0.016;r=0.683,P=0.003;r=0.510,P=0.025),与CTX呈负相关(r=-0.645,P=0.008)。在骨量减少组,血清vaspin水平与HDL、P1NP、FN BMD及SMI呈正相关(r=0.349,P=0.041;r=0.339,P=0.045;r=0.483,P=0.035;r=0.450,P=0.039),与CTX呈负相关(r=-0.441,P=0.040)。logistic回归分析结果表明,血清vaspin水平(OR=0.774,95%CI:0.655~0.856,P=0.002)是老年男性骨质疏松症的保护因素。结论骨量减少及骨质疏松老年男性血清vaspin水平降低,高水平血清vaspin可能是老年男性骨质疏松症的保护因素。

Transition to adulthood: A critical role for exercise in building overall well-being

A growing number of multidisciplinary studies have reported the beneficial effects of physical activities towards the development of overall well-being and the reduction of chronic illnesses. Physical inactivity is a serious worldwide problem and is considered the key lifestyle factor that negatively influences health and function of individuals. Here we propose that growth kinetics of body and mind and associated disproportionate physical activity may have considerable effects on the increased physical and mental illnesses and premature death rates currently observed in mid to late adulthood people. Children and young adults, being in exponential growth phase and self-motivated to engage in physical activity, possess more cognition, resilience, and mind-body-emotion-spirit integration. In contrast, as our body transitions into adulthood, there is a decline in the growth of body and mind. Furthermore, in this period, adults experience the increased stressors of career and financial demands, time pressure, and family responsibilities. The decline in growth combined with prolonged stress appears to result in reduced cognition, resilience, and mind-body-emotion-spirit integration, leading to sedentary and other faulty lifestyles, which could further lead to a predisposition to maladaptive behaviours and various chronic diseases at a later stage. In agreement with this, currently more than two thirds of the adult population across the world are physically inactive and are failing to perform the daily recommended guidelines of moderate to vigorous exercise. As negative changes and faulty lifestyles begin to occur during and after adulthood transition, creating awareness in people between 29 to 35 years of age about mindful exercise should be considered a national priority. This would allow adults to achieve overall well-being, and increased productivity and life expectancy, reducing health care-associated economic burden placed on the nation.

体检人群体成分及肥胖率的检测分析

目的检测体检人群身体组成成分,分析体检人群不同年龄段身体成分差异,分析人群超重率、肥胖率以及体重指数的影响因素。方法选取2016年至2023年体检人群为研究对象,根据性别及年龄分组,使用人体成分分析仪测定BMI、肌肉量、体脂率、脂肪量等身体组分,分析不同年龄段的身体组分是否具有差异,用不同方法判定人群的超重率、肥胖率是否有差异。结果男性各年龄段之间的BMI、脂肪量、体脂率、肌肉量、腰臀比等指标均具有统计学差异(P<0.001),女性各年龄段之间BMI、脂肪量、体脂率、肌肉量、腰臀比等指标均具有统计学差异(P<0.001)。BMI、脂肪量、体脂率、肥胖度等指标在男性、女性之间均具有统计学差异(P<0.001)。男性和女性在分别使用BMI法和BFP法判定的超重率和肥胖率时,判定方法不同,超重率和肥胖率不同。经多重线性回归分析,年龄、体脂率、脂肪量是影响体重指数的主要因子。结论体检人群超重率、肥胖率均较高,且男性远高于女性,存在健康风险,应调整饮食和生活习惯,适当增加运动,保护身体建康,并引起公共卫生领域的关注。

甘南藏族人体组成成分分析

目的揭示甘南藏族人体组成成分特点。方法采用生物电阻抗法,测量了甘南藏族410例成人(男性221,女性189)人体组成成分。运用SPSS 20.0统计学软件对数据进行处理。结果相关分析结果显示,男性总肌肉量、推定骨量、躯干肌肉量随年龄增长而减小,水分率、内脏脂肪等级及躯干脂肪率随年龄增长而增大;女性身高及躯干肌肉量随年龄增长而减小,体重、总体脂率、身体质量指数(BMI)、内脏脂肪等级、右上肢脂肪率、右上肢肌肉量、左上肢脂肪率及左上肢肌肉量、右下肢脂肪率、左下肢脂肪率、左下肢肌肉量及躯干脂肪率随年龄增长而增大。单因素方差分析显示,男性水分率、内脏脂肪等级、躯干脂肪率及躯干肌肉量4项指标值年龄组间差异均具有统计学意义,其余14项指标值年龄组间差异均无统计学意义;女性体重、身高、总体脂率、总肌肉量、推定骨量、BMI、内脏脂肪等级、右上肢脂肪率、右上肢肌肉量、左上肢脂肪率、左上肢肌肉量、右下肢脂肪率、左下肢脂肪率、左下肢肌肉量、躯干脂肪率及躯干肌肉量16项指标值年龄组间差异具有统计学意义,其余2项指标值年龄组间差异均无统计学意义。u检验结果表明,男性体重、总肌肉量、推定骨量、水分率、四肢肌肉量及躯干肌肉量高于女性,女性总体脂率、四肢脂肪率、内脏脂肪率及躯干脂肪率高于男性。根据BMI判定,甘南藏族男性、女性超重;根据体脂肪率,甘南藏族男性属于非肥胖,女性属于肥胖。结论在13个族群中,甘南藏族男性、女性BMI、总体脂率较大。

人体成分与脂肪细胞因子在妊娠期糖尿病患者中的关系研究

目的:探讨妊娠期女性的人体成分与脂肪细胞因子在妊娠期糖尿病(GDM)风险之间的关系。方法:选择本院常规产前检查单胎自然受孕GDM孕妇90例为GDM组,另选择同期单胎正常妊娠孕妇219例为对照组(NGT组)。在妊娠24~28周时,用生物阻抗法测定其人体成分。分析孕前体质量指数(BMI)、体脂百分比(FMP)、去脂体质量百分比(FFMP)、细胞外液/细胞内液(ECW/ICW)、体脂指数(FMI)等人体成分与GDM的关系。所有入组孕妇同期采用酶联免疫吸附法(ELISA)检测循环脂联素、脂肪酸结合蛋白4(FABP4)、瘦素以及空腹胰岛素(FINS)水平,并分析其与人体成分各指标的关系。结果:①GDM组脂联素低于NGT组,而瘦素高于NGT组(P<0.05)。②GDM组FMP、ECW/ICW、FMI显著高于NGT组(P<0.05),单因素回归分析显示孕前BMI、FMP、FMI、ECW/ICW是GDM的危险因素(OR>1,P<0.05)。而多因素分析显示仅FMP升高与GDM发病风险显著相关,是其发病的独立危险因素(OR>1,P<0.05),FFMP、MP、PP、M/F是GDM的保护因素(OR<1,P<0.05)。③GDM组,胰岛素抵抗指数(HOMA-IR)与FMI呈正相关(r>1,P<0.05),与PP呈负相关(r<1,P<0.05)。④ROC曲线显示,孕前BMI、FMP、ECW/ICW、FMI对GDM的诊断价值相似,孕前BMI、FMP和FMI相比差异无统计学意义(P>0.05),但略优于ECW/ICW(P<0.001)。结论:妊娠期的人体成分与患GDM的风险有关。FMP升高与发展为GDM的风险增加有关,FMP越高,GDM的风险越高。孕前BMI、FMP、FMI对GDM的诊断效能相似。

围绝经期及绝经后期女性人体体成分与腰椎骨密度的相关分析

目的探讨围绝经期及绝经后期女性人体体成分与腰椎骨密度(bone mineral density,BMD)之间的关系,进一步分析该人群骨量减少的影响因素。方法招募2021年10月至2024年3月于首都医科大学附属北京妇产医院内分泌科就诊的围绝经期及绝经后期女性300例为研究对象。采用定量电子计算机断层扫描技术(quantitative computed tomography,QCT)测量腰椎骨密度,根据测量结果分为骨量正常组和骨量减少组,采用肌肉功能分析仪测定所有受试者的体质量、脂肪、下肢肌肉、膝关节活动等人体成分情况,采用更年期症状全面评估量表采集所有研究对象的年龄、绝经状态及活动类型。采用单因素方差分析比较骨量正常组和骨量减少组的人体体成分之间的差异性,采用多因素Logistic回归分析探讨骨量减少的危险因素。结果300例研究对象中,围绝经期女性148例(49%),平均年龄(51.40±5.03)岁;绝经后期女性152例(51%),平均年龄(53.59±6.04)岁。绝经后期女性的骨密度低于围绝经期女性,差异有统计学意义(P<0.05)。骨量减少组118例(39%),骨量正常组182例(61%)。骨量减少组女性年龄、脂肪百分比、绝经后期占比和无锻炼占比均高于骨量正常组,差异有统计学意义(P<0.05);而下肢肌肉分布系数、下肢肌力和有锻炼占比均低于骨量正常组,差异有统计学意义(P<0.05)。Spearman相关性分析结果表明围绝经期和绝经后期女性BMD与年龄、脂肪百分比、绝经后期占比均呈显著负相关(r=-0.492、-0.125、-0.287,P<0.05),而与下肢肌肉分布系数、下肢肌力、有锻炼占比均呈显著正相关(r=0.143、0.180、0.193,P<0.05)。二元Logistic回归分析结果显示,年龄大、脂肪百分比大、下肢肌肉分布少、锻炼少是骨量减少的危险因素(P<0.05)。结论与围绝经期女性相比,绝经后期女性的腰椎骨密度明显降低,围绝经期及绝经后期女性腰椎骨密度与人体体成分及活动类型密切相关,其中年龄大、脂肪百分比大、下肢肌肉分布少、锻炼少是骨量减少的危险因素(P<0.05)。建议临床医生关注此时期女性的腰椎骨密度及人体体成分的变化,以便通过及时合理的干预措施来提高她们的生活质量,预防骨质疏松的发生。

不同杀菌温度炖煮燕窝对小鼠体成分的调节作用

为研究不同杀菌温度对燕窝功能特性的影响,以不同杀菌温度炖煮燕窝为研究对象,将40只7周龄C57BL/6N雄性小鼠随机分为空白对照组、干燕窝组、95℃杀菌炖煮燕窝组、115℃杀菌炖煮燕窝组,口服给予小鼠炖煮燕窝匀浆90 d,通过测定小鼠的体成分、能量代谢及肠道菌群,探究炖煮燕窝对小鼠生长特性的影响。结果表明,95℃杀菌炖煮燕窝可以显著提升小鼠的瘦肉率,降低小鼠的脂肪含量;对小鼠基础代谢无显著影响,在属水平上,可以显著提高小鼠肠道菌群中毛螺菌和乳酸菌的相对丰度,降低脱硫弧菌的相对丰度;且小鼠体成分与肠道菌群具有显著相关性,小鼠瘦肉率含量与灌服95℃杀菌炖煮燕窝的小鼠肠道菌群相对丰度呈正相关,小鼠脂肪含量与灌服95℃杀菌炖煮燕窝的小鼠肠道菌群相对丰度呈负相关,95℃杀菌炖煮燕窝可以通过调节小鼠肠道菌群改变小鼠体成分含量。综上,95℃杀菌炖煮燕窝可改变小鼠体成分含量,提高肠道菌群的丰富度和多样性,有效改善小鼠肠道菌群结构,通过相关性分析发现肠道菌群的改善是调控体成分的潜在机制。

克罗恩病患者身体成分改变的研究

克罗恩病(Crohn’s disease,CD)是一种以复发和缓解交替进行为特点的炎症性肠病,病程渐进且尚不能完全治愈。近年来CD患者身体成分的改变日益受到关注,内脏脂肪或肌肉质量的变化可反映患者的营养状态,并可能影响疾病的进展情况。明确身体成分改变与疾病炎症状态及预后之间的联系,提前采取干预措施预防或逆转不良变化趋势,将对CD的临床管理产生重要影响,且有望为CD患者提供新的治疗方法。本文对CD患者身体成分改变的研究现状与进展作一概述,以帮助临床优化疾病管理策略,为改善患者预后提供新思路。

上海城市公共开放空间夏季小气候及舒适度

基于2006年5—8月上海城区5种类型公共开放空间(广场、喷泉、草坪、廊道、林地)的空气温度、相对湿度、风速和辐射强度等小气候指标,分析了各空间类型对小气候的调节作用,并采用体感气象指数(discomfortindex,DI)作为评价指标,比较了各空间类型对人体舒适程度影响的差异.结果表明:上海市5种类型公共开放空间的平均温度、相对湿度等小气候因子存在一定差异;平均气温依次为广场>草坪>喷泉>廊道>林地;平均空气相对湿度依次为林地>廊道>喷泉>草坪>广场;广场面积、喷泉水体附近的风速及风向、草坪的草种类型、廊道的宽度及乔木盖度、林地的盖度及乔木林冠层高度等非气候指标分别与各自空间的气候指标呈显著相关.与其他3种空间类型相比,林地和廊道具有明显的遮荫、降温、增湿作用,对小气候的调节能力更佳.

人体组成的活体测量技术及评价

人体组成的活体测量技术是人体组成学研究的重要内容,近年来有了长足的发展。我们概述了人体组成活体测量技术的现状,介绍了目前常用的测量方法,如人体测量法、代谢产物方法、密度测定法、稀释方法、总体钾法、中子活化分析法、生物电阻抗测定法、双能源X线吸收测定法、影像学方法和红外线干涉法等,并就这些技术的原理、方法、应用进行了简述。

渐变的光周期和温度对布氏田鼠能量代谢和身体成分的影响

为探讨在同时逐渐缩短光照时间和降低温度的过程中,动物能量代谢水平和身体成分的适应性变化,我们以成年雄性布氏田鼠为对象,测定了温度为20℃和光周期为12L∶12D (对照组),以及从温度为20℃和长光照条件(16L∶8D)逐渐转换到温度为4℃和短光照条件(8L∶16D)的过程中(实验组),其体重、静止代谢率和能量摄入的变化,以及经过8周驯化后身体器官和组织重量的变化。结果发现:实验组动物的体重增长率低于对照组。在驯化期间,静止代谢率无组内和组间差异。实验组动物的干物质摄入、能量摄入和消化能等组内差异不明显,但对照组动物在驯化的第8周显著降低。实验组动物的能量摄入水平在驯化后显著升高;小肠和胃的干重,以及小肠和心脏等器官的湿重也都显著高于对照组。结果表明,布氏田鼠能够采取降低体重、增加能量摄入和调整体内某些器官和组织重量的方式来适应变化的环境条件。

甘肃兰州市区城镇居民体成分分析

目的分析甘肃兰州市区城镇成人居民体成分和脂肪分布随年龄变化的特点及发展趋势,为改善居民的身体状况提供理论依据。方法采用生物电阻抗法(日本产MC-180型人体成分分析仪)对1357名男女居民进行测试,对测试结果进行统计学分析。结果 20~79岁年龄段男女性居民体脂率、腰臀比(WHR)随年龄的增长而递增。蛋白质总量、肌肉总量、推定骨量、身体水分、身体质量指数(BMI)值随年龄的增长呈先升后降的趋势。内脏脂肪男、女性均随年龄的增长而增长,皮下脂肪男性随年龄的增长呈先升后降的趋势,女性则随年龄的递增而递增。结论男性居民在20~岁年龄段后、女性在40~岁年龄段后出现了腹内型肥胖,男性在30~岁年龄段后,女性在60~岁年龄段后出现超重,超出了警戒范围。

磁共振图像实现人体体成分数字化的研究

采用对人体无任何辐射的磁共振(MR)方法对人体进行全身扫描,结合各种图像软件Photoshop,Matlab对 获得的磁共振图像(MRI)进行数字化分析,获得人体内各种组织质量,并用获得的结果与生物电阻抗人体成分测试仪 Inbody3.0及皮褶法测试的结果进行比较,表明体脂肪质量生物电阻抗法与MRI分析法的测量结果差别为Δm(脂肪)= (0.3±1.65)/kg,Δw(脂肪)=(0.5±2.24)%,皮褶法与MRI分析法结果的Δw(脂肪)=(3±3.62)%,说明生物电阻抗 法比皮褶法的测量结果更加准确,其原理更为科学.