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Height/Length and Weight Growth Curves and Growth References of Children Aged 0 - 7 in Chongqing by GAMLSS
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作者 Qian Chen Jiaxiu Liu +1 位作者 Kaocong Tian Zhaohai Liu 《Health》 2020年第2期86-98,共13页
Aim: Using the generalised additive model for location, the scale and shape (GAMLSS), the standard of height (length), weight and percentage curve of children were formulated to understand the growth law in Chongqing ... Aim: Using the generalised additive model for location, the scale and shape (GAMLSS), the standard of height (length), weight and percentage curve of children were formulated to understand the growth law in Chongqing and to provide a reference for clinical and preventive health care work of paediatrics in West China. Methods: Data were collected from the health clinic dataset of children aged 0 - 7 years in the Department of Child Health Care of a Third-Class A hospital in Chongqing from 2010 to 2017. By applying the GAMLSS technology and taking D(μ, σ, ν, τ) as the specific distribution form, BCT as the link function, P-spline function and cubic splines function as the smoothing function, the unit value of age-specific standard deviation of height (length) and weight were obtained, and the percentile map was drawn. Results: Based on the principle of minimum AIC and SBC values, BCT distribution was chosen as the model of the link function. Fitting results of height (length) and weight parameters of boys and girls, standard deviation tables of age and percentile curves were obtained. Conclusions: This study was an exploration of using GAMLSS method to establish a reference value range in the field of children’s growth and development in China. It could supplement the relevant data of Chongqing area for Reference standard for growth and development of children under 7 years of age in China, and also provide a reference for the rational diagnosis of children’s short stature and malnutrition in Chongqing. 展开更多
关键词 CHILDREN HEIGHT weight growth Curve GAMLSS
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Statural and Weight Growth of Low Birth Weight at 9 Months
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作者 Modou Gueye Amadou Sow +6 位作者 Djibril Boiro Youssouf Mmadi Ibrahim Aissatou Cisse Bathily Benjeloun Amane Assane Sylla Papa Moctar Faye Ousmane Ndiaye 《Open Journal of Pediatrics》 2022年第1期19-25,共7页
Introduction: Low birth weight (LBW) is defined as a birth weight 2500 g at birth, regardless of the term of pregnancy. The objective of this study is to evaluate their stature and weight growth from 0 to 9 months of ... Introduction: Low birth weight (LBW) is defined as a birth weight 2500 g at birth, regardless of the term of pregnancy. The objective of this study is to evaluate their stature and weight growth from 0 to 9 months of corrected age (CA) in Senegal. Methodology: This is a prospective, descriptive, and analytical cohort follow-up up to 9 months of CA including all live newborns of LBW hospitalized and followed up from 01 August 2019 to 31 May 2020. World Health Organization growth charts were used to assess stature and weight growth. Results: During the study 136 LBW newborns were included. The mean gestational age was 32 weeks of amenorrhea. At discharge, 46 children (33.82%) were exclusively breastfed. At birth, the mean weight was 1487 g (3<sup>rd</sup>-10<sup>th</sup> percentile) and the mean height was 41.52 cm (10<sup>th</sup>-25<sup>th</sup> percentile). At 9 months of CA, the mean weight was 8119 g (median) and the mean height was 74 cm (median). The children had achieved satisfactory growth in weight (84%) and height (89%). At 9 months of CA, 27% of the children were behind in one of the four areas of psychomotor development. Conclusion: At the end of 9 months of CA, stature and weighted growth was normal. 展开更多
关键词 LOW-BIRTH-weight growth STATURE weight CHILD Senegal
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Enhanced Efficiency of Milk Utilization for Growth in Surviving Low-Birth-Weight Piglets 被引量:4
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作者 Reza Rezaei Darrell A. Knabe +2 位作者 Xilong Li Shuo Feng Guoyao Wu 《Journal of Animal Science and Biotechnology》 SCIE CAS 2011年第2期73-83,共11页
This study determined effects of birth weights (0.70 to 1.09, 1.10 to 1.49, 1.50 to 1.89, and ≥ 1.90 kg) on the efficiency of milk utilization for growth in sow-reared piglets. One-hundred-sixty piglets from 18 mul... This study determined effects of birth weights (0.70 to 1.09, 1.10 to 1.49, 1.50 to 1.89, and ≥ 1.90 kg) on the efficiency of milk utilization for growth in sow-reared piglets. One-hundred-sixty piglets from 18 multiparous sows ( Landrace × Large White) were individually weighed immediately after birth ( day 0) and at 7-day intervals for 35 days. Milk consumption of piglets was determined weekly using the weigh-suckle-weigh method. Deaths of piglets were recorded daily. Piglets with the lightest birth weight had the highest incidence of mortality. Birth weights between 0.70 and 1.89 kg were positively as- sociated with average dally gains (ADG, g/day ) during the suckling period ( P 〈 0.01 ). Compared with piglets having birth weights of 1.50 to 1.89 kg, birth weights ≥ 1.90 kg did not confer any additional benefit on preweaning survival or ADG. Colostrum or milk consumption per kilogram of body weight among low-, normal-, and large-birth-weight piglets did not differ in the first week. At days 14 to 35, milk consumption of piglets ( g/kg BW/day ) increased (e 〈 0. 01 ) but the ratio of gain to milk consumption decreased ( P 〈 0.01 ) progressively, as their birth weights increased from 0.70 to ≥1.90 kg. Additionally, surviving low-birth-weight piglets had a higher relative growth rate (%/day ) than normal-and large-birth- weight piglets. Based on these novel findings, it is imperative that great efforts be made to improve the survival of low-birth-weight piglets so as to increase the efficiency of nutrient utilization by both lactating sows and suckling piglets. 展开更多
关键词 birth weight growth rate MORTALITY PIGLETS
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EFFECT OF RATION, TEMPERATURE AND BODY WEIGHT ON GROWTH OF BLACK PORGY,SPARUS MACROCEPHALUS (B.) 被引量:1
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作者 李军 徐世宏 徐长安 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 1997年第4期289-295,共7页
Growth of black porgy. Sparus macrocephalus was studied experimentally at four ration lerels from starvation to sltiation and tour temperatures ranging from 14.8 to 26.8℃ .At maximum rations. the specific growth rate... Growth of black porgy. Sparus macrocephalus was studied experimentally at four ration lerels from starvation to sltiation and tour temperatures ranging from 14.8 to 26.8℃ .At maximum rations. the specific growth rate (SGR) increased with temperature and was a negative linear function of body weight. The relationship betaren SGR and ration levels was a decelerating curve. Stepwise mpgression was used to derelop the predictive models for the specific growth rates. Maintenance rations and optimum ratlons both increased with increased temperature. The relationship between maintenance. optimum rations and body welght wds influenced by temperuture. Conversion efficiencies increased with ration from zero at maintenance ration to a peak at the optimum ration, then declined with further inceased ration. 展开更多
关键词 RATION TEMPERATURE body weight growth SPARUS MACROCEPHALUS
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Therapeutic effect of nerve growth factor on cerebral infarction in dogs using the hemisphere anomalous volume ratio of diffusion-weighted magnetic resonance imaging 被引量:9
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作者 Yong Wang Hui Zhang +5 位作者 Zhe Wang Zuojun Geng Huaijun Liu Haiqing Yang Peng Song Qing Liu 《Neural Regeneration Research》 SCIE CAS CSCD 2012年第24期1873-1880,共8页
A model of focal cerebral ischemic infarction was established in dogs through middle cerebral artery occlusion of the right side.Thirty minutes after occlusion,models were injected with nerve growth factor adjacent to... A model of focal cerebral ischemic infarction was established in dogs through middle cerebral artery occlusion of the right side.Thirty minutes after occlusion,models were injected with nerve growth factor adjacent to the infarct locus.The therapeutic effect of nerve growth factor against cerebral infarction was assessed using the hemisphere anomalous volume ratio,a quantitative index of diffusion-weighted MRI.At 6 hours,24 hours,7 days and 3 months after modeling,the hemisphere anomalous volume ratio was significantly reduced after treatment with nerve growth factor. Hematoxylin-eosin staining,immunohistochemistry,electron microscopy and neurological function scores showed that infarct defects were slightly reduced and neurological function significantly improved after nerve growth factor treatment.This result was consistent with diffusion-weighted MRI measurements.Experimental findings indicate that nerve growth factor can protect against cerebral infarction,and that the hemisphere anomalous volume ratio of diffusion-weighted MRI can be used to evaluate the therapeutic effect. 展开更多
关键词 diffusion-weighted MRI nerve growth factor hemisphere anomalous volume ratio cerebral infarction treatment NEUROPROTECTION brain regeneration neural regeneration
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Evaluation of Growth of Agricultural Listed Companies Based on AHP Weighting Method
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作者 Hong LU Yan CHENG +2 位作者 Huan GAO Changhai ZHOU Qinqin WANG 《Asian Agricultural Research》 2014年第12期23-25,共3页
Agriculture is the foundation of national economy,and agricultural development is related to the rapid development of long-term stability of the society and economy. Agriculture includes farming,forestry,animal husban... Agriculture is the foundation of national economy,and agricultural development is related to the rapid development of long-term stability of the society and economy. Agriculture includes farming,forestry,animal husbandry,and fisheries. Agricultural listed company as an agricultural enterprise " leader",which directly affects the development of the entire growth of the agricultural industry development and policy,so the study of agricultural listed company's growth is particularly important. This paper uses AHP weighting method to evaluate 2012 financial data on the growth of agricultural listed companies. 展开更多
关键词 AHP weighting method AGRICULTURAL LISTED COMPANIES
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贵州地方鸡种体重生长曲线的拟合分析
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作者 龙霞 李维 +5 位作者 杨书含 李辉 吴胜 田应平 田旭玲 肖涛 《畜牧与兽医》 CAS 北大核心 2024年第1期1-5,共5页
为探究贵州省赤水乌骨鸡、黔东南小香鸡、乌蒙乌骨鸡、威宁鸡和贵州黄鸡这5个地方鸡种生长发育规律,采用Logistic、Gompertz和von Bertalanffy 3种非线性模型对5个地方鸡种的生长曲线进行拟合,选取5个品种鸡各60只,公母各30只,测定0、2... 为探究贵州省赤水乌骨鸡、黔东南小香鸡、乌蒙乌骨鸡、威宁鸡和贵州黄鸡这5个地方鸡种生长发育规律,采用Logistic、Gompertz和von Bertalanffy 3种非线性模型对5个地方鸡种的生长曲线进行拟合,选取5个品种鸡各60只,公母各30只,测定0、2、4、6、8、10、12、14、16、18周龄时的体重。结果:5个品种鸡的生长趋势一致,3个模型均能较好地拟合5个品种鸡的生长变化情况,拟合度均在0.98以上,其中von Bertalanffy模型对5个品种鸡的生长曲线拟合效果最好;同时期的鸡体重以贵州黄鸡最重,黔东南小香鸡最轻,赤水乌骨鸡、乌蒙乌骨鸡和威宁鸡相近;5个品种鸡的拐点周龄分别为9.2、7.9、7.3、8.9和8.4,拐点体重分别为870.71、509.18、708.29、834.35和945.52 g。通过拟合的生长曲线模型对鸡体重进行评估,可为贵州省地方鸡的科学饲养、品种资源利用及选育提供依据。 展开更多
关键词 地方鸡 品种 体重 生长曲线 拟合分析 贵州
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INFLUENCES OF MOLECULAR WEIGHT AND BRANCHING PARAMETER OF LACQUER POLYSACCHARIDE ON THE GROWTH OF LEUCOCYTES
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作者 张俐娜 丁琼 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1995年第2期107-111,共5页
A method of determining branching parameter of lacquer polysaccharide wasestablished by acid-base back-titration of terminal uronic acid of branches. The branchingfactors obtained are in agreement with the values dete... A method of determining branching parameter of lacquer polysaccharide wasestablished by acid-base back-titration of terminal uronic acid of branches. The branchingfactors obtained are in agreement with the values determined by colorimetric method withcarbazole and the results estimated by using Zimm-Stockmayer equation from viscositydata. Influences of molecular weights and branching factors of five fractions of lacquerpolysaccharide on the bioactivities were studied. The results show that the polysaccharideshave bioactivities in motivating the growth of leucocytes, and the effect increases with thedecrease of molecular weight and branching factor in the range studied (17×10~4 >M_w>4×10~4). 展开更多
关键词 Lacquer polysaccharide Molecular weight Branching parameter Structure-activity relation Bioactivity growth of leucocyte
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Feeding Behavior, Body Weight and Growth Rate during Post-Deprivation Period in Rats
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作者 Antonio López-Espinoza Alma Gabriela Martínez Moreno +6 位作者 Virginia Gabriela Aguilera Cervantes Elia Valdé s Miramontes Luis Alfonso Mojica Contreras Monica Navarro-Meza Claudia Patricia Beltrán-Miranda Ana Cristina Espinoza-Gallardo 《Food and Nutrition Sciences》 2015年第14期1307-1315,共9页
Deprivation is an environmental experience that organisms are continually exposed to. However, few studies analyze deprivation effects on the consumption pattern during the post-deprivation period systematically. The ... Deprivation is an environmental experience that organisms are continually exposed to. However, few studies analyze deprivation effects on the consumption pattern during the post-deprivation period systematically. The aim of this study was to evaluate the deprivation effect on feeding pattern, growth rate and body weight during post-deprivation. Sixteen albino rats (3 months old at the beginning of the experiment) were exposed to 72-hour total food deprivation every 15 days. Food and water were freely available during non-deprivation periods. Rats completed three cycles comprised by a free access period followed by food deprivation. Once deprivation was removed, food and water consumption increased and then decreased, while body weight was recovered. Growth rate increased after every deprivation period and reached similar levels to those presented by the control group. Depriving rats from one commodity (i.e., food) cause them to restrain their consumption of the other freely available commodity (i.e., water). Results confirm that food deprivation modifies growth rate, water and food consumption. Additionally, during post-deprivation period, differences between males and females were not registered. 展开更多
关键词 Body weight FOOD INTAKE Water INTAKE Post-Deprivation PERIOD growth Rate
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重度子痫前期患者孕晚期血清尿素氮/肌酐比值与胎儿体重的关系研究
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作者 张孝认 周旭平 +1 位作者 徐琼飞 吴巧萍 《浙江医学》 CAS 2024年第20期2167-2172,共6页
目的探讨重度子痫前期(PE)患者孕晚期血清尿素氮(BUN)/肌酐(Cr)比值与胎儿体重的关系。方法采用病例对照研究,选取2021年1月至2022年12月宁波市医疗中心李惠利医院及宁波大学附属妇女儿童医院收治的孕晚期重度PE患者200例,另选取同期入... 目的探讨重度子痫前期(PE)患者孕晚期血清尿素氮(BUN)/肌酐(Cr)比值与胎儿体重的关系。方法采用病例对照研究,选取2021年1月至2022年12月宁波市医疗中心李惠利医院及宁波大学附属妇女儿童医院收治的孕晚期重度PE患者200例,另选取同期入院待产的非高血压孕妇200例作为对照。收集孕妇临床资料,抽取空腹静脉血5 mL检测BUN、Cr等生化指标,观察重度PE患者BUN/Cr比值变化及胎儿体重特点;重度PE患者中发生胎儿生长受限(FGR)58例作为FGR组,未发生FGR 142例作为非FGR组,比较两组间BUN/Cr比值等血清生化指标及临床特点差异,分析重度PE患者孕晚期血清BUN/Cr比值对FGR发生的影响,血清BUN/Cr比值与胎儿出生体重的相关性。结果与非高血压组比较,重度PE组BUN/Cr比值较高,胎儿FGR发生率较高,胎儿出生体重较小,差异均有统计学意义(均P<0.05);BUN/Cr比值是重度PE患者发生FGR的独立危险因素(OR=1.176,95%CI:1.100~1.258,P<0.001);孕前BMI、孕期增重、分娩孕周与胎儿出生体重均呈正相关(r=0.158、0.173、0.798,P=0.027、0.014、<0.001),BUN/Cr、尿酸水平与胎儿出生体重均呈负相关(r=-0.477、-0.226,P<0.001、0.001);排除孕前BMI、孕期增重、分娩孕周及尿酸水平对胎儿出生体重的影响外,BUN/Cr比值与胎儿出生体重呈负相关(r=-0.389,P<0.001)。结论重度PE患者血清BUN/Cr比值与胎儿出生体重呈负相关,是重度PE患者发生FGR的独立危险因素。 展开更多
关键词 子痫前期 胎儿生长受限 出生体重 尿素氮 肌酐
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贵州北部云南光唇鱼野外和驯养种群的生长模式研究
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作者 肖贵榜 张浩然 +6 位作者 廖丽 陆武军 毛茜 陈兴科 周林 鲍娟 王礼节 《贵州农业科学》 CAS 2024年第5期68-75,共8页
【目的】探明贵州北部云南光唇鱼(Acrossocheilusyunnanensis)自然栖息环境和驯养条件下体长与体重的关系,分析其群体生长规律,为当地云南光唇鱼资源的保护和开发提供参考。【方法】测定野外种群和驯养种群个体的体长、体重,利用单因素... 【目的】探明贵州北部云南光唇鱼(Acrossocheilusyunnanensis)自然栖息环境和驯养条件下体长与体重的关系,分析其群体生长规律,为当地云南光唇鱼资源的保护和开发提供参考。【方法】测定野外种群和驯养种群个体的体长、体重,利用单因素方差分析、t检验、幂函数回归等方法分析有关指标。【结果】云南光唇鱼野外种群体长为80~171 mm,平均体长为(134.55±20.34)mm;驯养种群体长为150~245 mm,平均体长为(167.51±15.18)mm;平均体长驯养种群显著大于野生种群。云南光唇鱼野生种群体重为21~112 g,平均体重为(69.92±18.99)g;驯养种群体重为52.9~143.0 g,平均体重为(78.03±18.42)g;驯养种群平均体重显著大于野生种群。云南光唇鱼野外种群体长和体重均呈左偏分布,驯养种群均呈右偏分布。从变异系数看,云南光唇鱼野外种群体长和体重整齐度均低于驯养种群。云南光唇鱼体长-体重关系式野生种群为W=0.0011L^(1.9896)(n=100,R^(2)=0.9847),驯养种群为W=0.0002L^(2.2119)(n=100,R^(2)=0.7758)。野生种群与驯养种群体长与体重参数a值和b值分别为0.000005~0.009397和1.5176~2.8341。野生种群与驯养种群的参数a值呈由高到低的变化趋势,参数b值呈与a值相反的变化趋势。单因素方差分析表明,云南光唇鱼野外种群与驯养种群各阶段体长与体重关系参数a值、b值差异不显著。t检验表明,野外种群b值与3差异极显著,驯养种群b值与3差异不显著。【结论】贵州北部云南光唇鱼野外种群生长为负异速生长,人工驯养条件下为等速生长。贵州北部云南光唇鱼野生环境优于驯养试验环境,天然栖息环境和驯养环境的综合环境条件均较差。 展开更多
关键词 云南光唇鱼 野生种群 驯养种群 生长模式 体长-体重相关性(LWR) 芙蓉江
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动物源营养液对卷叶霸王空气凤梨新叶生长及矿质元素含量影响
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作者 尹金华 汪华清 张惠贻 《热带农业科学》 2024年第7期42-46,共5页
为分析动物源营养液在空气凤梨上的应用效果,以‘卷叶霸王’空气凤梨为研究对象,以清水作对照,研究动物源营养液、磷酸二氢钾、尿素喷施后对空气凤梨新叶生长、单株增重、光泽度及矿质元素含量等的影响。结果表明,动物源营养液中含有钙... 为分析动物源营养液在空气凤梨上的应用效果,以‘卷叶霸王’空气凤梨为研究对象,以清水作对照,研究动物源营养液、磷酸二氢钾、尿素喷施后对空气凤梨新叶生长、单株增重、光泽度及矿质元素含量等的影响。结果表明,动物源营养液中含有钙、镁、铁、锌、硼和锰等矿质元素,空气凤梨在各种处理后3月内都没有新根萌出,均未出现肥害与微量元素中毒现象,光泽度没有明显差异。2.50‰营养液处理的第1小叶生长率增加41.58%,增加幅度最大。0.10‰动物源营养液处理单株增重率最高,2.50‰、0.50‰营养液处理次之;不同浓度动物源营养液处理间单株增重率差异不显著。与CK相比,3.33‰营养液处理、1.00‰营养液处理显著增加空气凤梨新叶内钙、镁、铁和锰含量,3.33‰动物源营养液处理的钙含量增加27.80%,镁含量增加23.71%,铁含量增加10.75%,锰含量增加104.41%。3.33‰营养液处理新叶内钙、镁、锰和硼含量显著高于1.00‰营养液处理,但铁和锌含量显著低于1.00‰营养液处理,生产上可以将动物源营养液作为卷叶霸王空气凤梨新型叶面营养肥进行合理开发与利用。 展开更多
关键词 动物源营养液 空气凤梨 新叶生长 单株增重 矿质元素含量
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肉羊不同杂交组合生长曲线模型筛选及分析
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作者 沈嘉玘 孙渭博 +8 位作者 施海娜 梁永虎 杨博辉 岳耀敬 袁超 郭婷婷 文亚洲 卢曾奎 张利平 《家畜生态学报》 北大核心 2024年第2期28-32,96,共6页
为研究肉羊不同杂交组合生长发育规律及评价适宜推广的杂交模式,以引进品种澳洲白、杜泊和萨福克羊为父本,湖羊为母本进行杂交试验。测定不同杂交组合1~6月龄体重,利用Brody、Logistic、Gompertz和Von Bertalanffy 4种模型分别拟合各杂... 为研究肉羊不同杂交组合生长发育规律及评价适宜推广的杂交模式,以引进品种澳洲白、杜泊和萨福克羊为父本,湖羊为母本进行杂交试验。测定不同杂交组合1~6月龄体重,利用Brody、Logistic、Gompertz和Von Bertalanffy 4种模型分别拟合各杂交组合体重发育过程,分析体重参数和模型估计值,评价杂交优势。结果表明:4种模型的拟合度(R^(2))均在0.95以上,其中Von Bertalanffy模型估计值最接近各个杂交组合的实测值,拟合效果最佳,拐点体重介于7.64~9.98 kg之间,拐点日龄在25~35 d之间。澳湖、杜湖和萨湖3个杂交组合最大日增重均在200 g左右(P>0.05),表明三者体重发育相近且适宜推广。Von Bertalanffy模型符合杂交羔羊体重实际生长现状,可为杂交羔羊早期体重发育评估提供依据。 展开更多
关键词 肉羊 杂交组合 体重 生长曲线模型 拟合分析
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基于熵权-模糊综合评价法的无人机多光谱春玉米长势监测模型研究
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作者 赵经华 马世骄 房城泰 《农业机械学报》 EI CAS CSCD 北大核心 2024年第8期214-224,共11页
为实现春玉米长势的快速监测,实时掌握田间作物的生长状况,本文以新疆维吾尔自治区克拉玛依地区种植的春玉米作为研究对象,利用无人机多光谱影像对春玉米进行长势监测。基于地面采集的春玉米叶片叶绿素含量、叶面积指数、地上部生物量... 为实现春玉米长势的快速监测,实时掌握田间作物的生长状况,本文以新疆维吾尔自治区克拉玛依地区种植的春玉米作为研究对象,利用无人机多光谱影像对春玉米进行长势监测。基于地面采集的春玉米叶片叶绿素含量、叶面积指数、地上部生物量和株高等数据,结合熵权法(EWM)和模糊综合评价法(FCE)建立综合长势指标CGMI_(EWM)和CGMI_(FCE)。通过无人机遥感影像数据构建光谱指数,并利用皮尔逊相关性分析法和方差膨胀因子确定模型最佳输入变量。采用偏最小二乘法(PLS)、随机森林回归(RF)及粒子群算法(PSO)优化RF模型建立春玉米长势反演模型,结合模型精度评价指标,最终确定春玉米空间影像长势分布图。结果表明,以CGMI_(EWM)和CGMI_(FCE)构建综合长势指标的相关性均高于单一长势指标的相关性;利用CGMI_(FCE)长势指标结合PSO-RF模型反演春玉米长势的效果最优,其决定系数(R^(2))为0.823,均方根误差(RMSE)为0.084%,相对分析误差(RPD)为2.345;研究区春玉米长势集中在生长正常(ZZ)等级,说明全区春玉米长势较为稳定。研究结果可为春玉米的田间管理提供科学依据。 展开更多
关键词 春玉米 熵权法 模糊综合评价法 综合长势指标 多光谱 无人机监测
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数字经济空间关联与区域经济增长——来自中国省域层面的经验证据
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作者 李磊 袁世昌 《新疆财经大学学报》 2024年第3期28-39,共12页
文章通过构建有向加权的空间关联网络刻画省域间数字经济空间关联关系,实证检验网络节点特征对区域经济增长的影响。研究发现:2013—2021年,我国数字经济整体发展水平显著提升,但区域间发展差异突出。我国省际数字经济空间关联网络的通... 文章通过构建有向加权的空间关联网络刻画省域间数字经济空间关联关系,实证检验网络节点特征对区域经济增长的影响。研究发现:2013—2021年,我国数字经济整体发展水平显著提升,但区域间发展差异突出。我国省际数字经济空间关联网络的通达性不强,呈现地理聚集性,具有典型的“核心-边缘”特征,由东部发达地区构成的净受益板块对数字资源的“虹吸效应”明显。此外,网络中节点地位的差异性明显,具有明显的层级分化特征,节点地区有向转变中心性和控制力对区域经济增长有显著的正向影响,说明数字经济产生的区域联动效应和关联溢出效应对提升经济发展水平具有重要的驱动作用。 展开更多
关键词 数字经济 空间关联 有向加权网络 社会网络分析 经济增长
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不同育幼方式及出生体重对大熊猫幼仔生长发育的影响
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作者 吴凯 赖加莹 +8 位作者 魏明 张亚辉 曾宪垠 魏荣平 曹晓涵 胡正泉 曾文 王承东 孔繁丽 《兽类学报》 CAS CSCD 北大核心 2024年第2期217-223,共7页
本研究以2012—2019年出生的80只大熊猫幼仔为研究对象,搜集幼仔早期发育(0~120日龄)过程中日增重、乳饲喂量及眼和耳发育情况等生长发育指标数据,分析了出生体重([50,100)g,n=7;[100,150)g,n=25;[150,200)g,n=37;[200,250)g,n=11)、喂... 本研究以2012—2019年出生的80只大熊猫幼仔为研究对象,搜集幼仔早期发育(0~120日龄)过程中日增重、乳饲喂量及眼和耳发育情况等生长发育指标数据,分析了出生体重([50,100)g,n=7;[100,150)g,n=25;[150,200)g,n=37;[200,250)g,n=11)、喂养方式(全母兽哺育,n=12;全人工育幼,n=10;人工与母兽交替育幼,n=58)和胎产仔数(单胎,n=14;双胎,n=66)对幼仔生长发育的影响。结果显示:(1)单胎幼仔的出生体重显著高于双胎幼仔(P<0.05);(2)幼仔早期生长发育状况与其育幼方式和出生体重密切相关(R2>0.9737),出生体重越高,幼仔体重增长率越快;(3)出生体重越轻的幼仔缩水量越少,但缩水量占出生体重比更高。此外,出生体重超轻的幼仔,其耳朵与眼睛的发育更慢。本研究可为大熊猫育幼方式的选择和改进提供一定的数据支撑。 展开更多
关键词 熊猫幼仔 育幼 出生体重 缩水量 生长发育
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塔里木鸽生长发育规律及生长曲线拟合分析
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作者 王钧冉 穆艾太尔·木塔力甫 +12 位作者 赵天心 王清正 王惠娥 杨宝钰 孙啸渊 杨娜 王亚茹 汤驰 依那木江·亚力买买提 努尔玛奴·克里木 热孜亚古丽·司马义勒 吾买尔江·艾孜木 格明古丽·木哈台 《特产研究》 2024年第3期85-92,共8页
为探究塔里木鸽早期生长发育规律,了解其品种特性。本研究采用亲鸽自繁自养的模式,测量0~28日龄乳鸽的体重、体尺指标进行关联性分析,利用Logistic、Gompertz和Von Bertalanffy 3种非线性生长模型对0~28日龄乳鸽体重进行曲线拟合分析。... 为探究塔里木鸽早期生长发育规律,了解其品种特性。本研究采用亲鸽自繁自养的模式,测量0~28日龄乳鸽的体重、体尺指标进行关联性分析,利用Logistic、Gompertz和Von Bertalanffy 3种非线性生长模型对0~28日龄乳鸽体重进行曲线拟合分析。结果显示,塔里木鸽累计体重持续增长,21日龄体重达到最大值,21日龄后体重小幅度降低。相对生长率随着体重增加持续降低,乳鸽7日龄绝对生长量最大,28日龄体重为负增长。不同日龄乳鸽的体重与各项体尺性状均呈极显著正相关(P<0.01),3种非线性模型均能较好的模拟塔里木鸽生长曲线,但Gompertz模型的拟合度最佳(R~2=0.988),拐点日龄为7.541 d,拐点体重为139.57 g,最大日增重为20.795 g,与实际测量值最为接近。塔里木鸽早期生长速度快,生长曲线呈“S”形,符合家禽生长发育的一般规律。Gompertz模型对塔里木鸽生长发育的体重拟合效果最佳,可根据此模型制定科学饲养管理模式,最大程度发挥其生产性能,为品种开发利用提供依据。 展开更多
关键词 塔里木鸽 体尺 体重 生长发育规律 生长曲线 关联性分析
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12种竹子的叶表型变异及其与环境因子的关系 被引量:1
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作者 冯云 张韫 +2 位作者 范少辉 刘广路 魏松坡 《西北林学院学报》 CSCD 北大核心 2024年第1期147-153,共7页
为了解不同竹种的叶表型变异特点及其受环境因子的影响,筛选出与抗寒性相关的叶表型性状,选取并测定分布在河南博爱和山东青岛的12种竹子的叶表型性状(长、宽、厚、长/宽、鲜质量、饱和鲜质量和干质量),进行变异分析、主成分分析、性状... 为了解不同竹种的叶表型变异特点及其受环境因子的影响,筛选出与抗寒性相关的叶表型性状,选取并测定分布在河南博爱和山东青岛的12种竹子的叶表型性状(长、宽、厚、长/宽、鲜质量、饱和鲜质量和干质量),进行变异分析、主成分分析、性状与环境因子的相关性分析并解析性状间的异速生长关系。结果表明,由博爱引至青岛后(温度降低但降雨量增加),蓉城竹和筠竹的叶表型性状在两地间均无显著性差异(P>0.05);黄秆乌哺鸡竹等8个刚竹属竹种至少有1个叶表型性状显著减小(P<0.05);福建茶秆竹、狭叶青苦竹有多个叶表型性状显著增大(P<0.05)。所有竹种叶质量的变异系数>20%,且青岛竹种叶质量的变异系数大于博爱,主成分分析也表明叶质量基本可以反映叶表型性状的全部信息。所有竹种的叶厚与温度因子显著正相关,与降雨量呈显著负相关(P<0.05),表现出了与环境相适应的变异特点。异速生长分析表明,12种竹子引至青岛后,叶厚与叶质量的生长速率增加,且叶质量的生长速率大于叶厚。研究结果表明,相比刚竹属竹种,福建茶秆竹与狭叶青苦竹对温度降低但降雨增加的青岛适应性更强,且叶质量是叶表型变异的主要因子,可作为竹类植物耐寒性的重要评价指标。 展开更多
关键词 竹子 叶片 表型性状 变异系数 叶质量 异速生长
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重组人生长激素治疗特发性矮小症的效果分析
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作者 余珊 聂小红 《中国社区医师》 2024年第18期56-58,共3页
目的:探讨重组人生长激素在特发性矮小症患儿中的应用效果。方法:选取2020年5月—2022年3月麻城市人民医院收治的特发性矮小症患儿68例作为研究对象,根据随机数字表法分为对照组与观察组,各34例。对照组给予常规营养治疗,观察组在对照... 目的:探讨重组人生长激素在特发性矮小症患儿中的应用效果。方法:选取2020年5月—2022年3月麻城市人民医院收治的特发性矮小症患儿68例作为研究对象,根据随机数字表法分为对照组与观察组,各34例。对照组给予常规营养治疗,观察组在对照组基础上给予重组人生长激素治疗。比较两组生长速度、体质量、血清胰岛素样生长因子-1(IGF-1)水平、胰岛素样生长因子结合蛋白-3(IGFBP-3)水平、维生素D水平及并发症发生情况。结果:治疗前,两组生长速度、体质量比较,差异无统计学意义(P>0.05);治疗后,两组生长速度、体质量高于治疗前,且观察组高于对照组,差异有统计学意义(P<0.001)。治疗前,两组IGF-1、IGFBP-3、维生素D水平比较,差异无统计学意义(P>0.05);治疗后,两组IGF-1、IGFBP-3、维生素D水平均高于治疗前,且观察组高于对照组,差异有统计学意义(P<0.001)。两组并发症总发生率比较,差异无统计学意义(P>0.05)。结论:重组人生长激素治疗特发性矮小症的效果较好,能够促进患儿生长发育,提高生长相关因子水平,且安全性较高。 展开更多
关键词 特发性矮小症 重组人生长激素 体质量 生长速度
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昆明犬幼犬生长发育规律研究
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作者 王孝义 徐虎 +5 位作者 李悦 万九生 鲁绍雄 曹振辉 王毅航 李杰 《养殖与饲料》 2024年第10期10-15,共6页
[目的]为揭示昆明犬幼犬的生长发育规律,进一步提升育种创新水平。[方法]选择24只8~27周龄昆明犬为试验对象,测定8个体尺指标(体高、体长、胸围、腹围、胸深、胸宽、荐高和管围)及体质量,并分析6个体尺指数(体长指数、胸围指数、胸宽指... [目的]为揭示昆明犬幼犬的生长发育规律,进一步提升育种创新水平。[方法]选择24只8~27周龄昆明犬为试验对象,测定8个体尺指标(体高、体长、胸围、腹围、胸深、胸宽、荐高和管围)及体质量,并分析6个体尺指数(体长指数、胸围指数、胸宽指数、体躯指数、臀高指数和管围指数)与体尺、体质量间的Pearson相关性。[结果]随着周龄的增加,昆明犬幼犬体尺、体质量逐步升高,且公犬的生长速度总体要快于母犬;生长强度呈现出先高后低的趋势,在0~8周龄最高;绝对生长呈现出先升高后降低的规律,在12~14周龄最大。不同生长阶段幼犬的体尺指数变化幅度在4.26%~21.70%。除腹围与管围、胸宽、体高、胸深、荐高、体长的Pearson相关性不显著外,其他指标间均存在极显著相关性。其中,荐高与体高、体长的相关系数分别为0.979和0.880,体质量与8个体尺指标的相关系数为0.353~0.740,均达到极显著水平。[结论]昆明犬幼犬主要部位生长发育均衡;加强幼犬0~8周龄的饲养管理有利于挖掘其生长潜能;根据体尺、体质量间的相关性可精简测定指标、优化选育方案。 展开更多
关键词 昆明犬幼犬 体尺 体质量 体尺指数 相关性 生长发育规律
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