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思维能力的成长评估 预览
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作者 谢小庆 《考试研究》 2020年第1期52-59,共8页
在快速变化的21世纪,学校最重要的任务是发展学生的思维能力。思维能力主要包含三项内容:第一,交流沟通能力;第二,逻辑推理能力;第三,审辩式思维。对体现在认知技能方面的思维能力,可以进行客观化测试。在思维能力评估中,不仅需要进行&q... 在快速变化的21世纪,学校最重要的任务是发展学生的思维能力。思维能力主要包含三项内容:第一,交流沟通能力;第二,逻辑推理能力;第三,审辩式思维。对体现在认知技能方面的思维能力,可以进行客观化测试。在思维能力评估中,不仅需要进行"达标评估",还需要重视"成长评估"。 展开更多
关键词 思维能力 审辩式思维 成长 成长评估
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A low-dimensional crystal growth model on an isotropic and quasi-free sustained substrate
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作者 卢晨曦 余森江 +3 位作者 李领伟 杨波 陶向明 叶高翔 《中国物理B:英文版》 SCIE EI CAS CSCD 2020年第3期420-426,共7页
A new crystal growth theoretical model is established for the low-dimensional nanocrystals on an isotropic and quasifree sustained substrate. The driven mechanism of the model is based on the competitive growth among ... A new crystal growth theoretical model is established for the low-dimensional nanocrystals on an isotropic and quasifree sustained substrate. The driven mechanism of the model is based on the competitive growth among the preferential growth directions of the crystals possessing anisotropic crystal structures, such as the hexagonal close-packed and wurtzite structures. The calculation results are in good agreement with the experimental findings in the growth process of the lowdimensional Zn nanocrystals on silicone oil surfaces. Our model shows a growth mechanism of various low-dimensional crystals on/in the isotropic substrates. 展开更多
关键词 crystal growth low-dimensional nanocrystals isotropic substrates preferential growth
Fibroblast growth factor signaling in non-alcoholic fatty liver disease and non-alcoholic steatohepatitis: Paving the way to hepatocellular carcinoma 预览
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作者 Matthias Ocker 《世界胃肠病学杂志:英文版》 SCIE CAS 2020年第3期279-290,共12页
Metabolic disorders are increasingly leading to non-alcoholic fatty liver disease,subsequent steatohepatitis,cirrhosis and hepatocellular carcinoma.Fibroblast growth factors and their receptors play an important role ... Metabolic disorders are increasingly leading to non-alcoholic fatty liver disease,subsequent steatohepatitis,cirrhosis and hepatocellular carcinoma.Fibroblast growth factors and their receptors play an important role in maintaining metabolic homeostasis also in the liver and disorders in signaling have been identified to contribute to those pathophysiologic conditions leading to hepatic lipid accumulation and chronic inflammation.While specific and well tolerated inhibitors of fibroblast growth factor receptor activity are currently developed for(non-liver)cancer therapy,treatment of non-alcoholic fatty liver disease and nonalcoholic steatohepatitis is still limited.Fibroblast growth factor-mimicking or restoring approaches have recently evolved as a novel therapeutic option and the impact of such interactions with the fibroblast growth factor receptor signaling network during non-alcoholic fatty liver disease/non-alcoholic steatohepatitis development is reviewed here. 展开更多
关键词 FIBROBLAST GROWTH FACTOR FIBROBLAST GROWTH FACTOR receptor Non-alcoholic fatty liver disease Non-alcoholic steatohepatitis Fibrosis Cirrhosis Hepatocellular carcinoma
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Variation analysis of growth traits of four poplar clones under different water and fertilizer management 预览
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作者 Ammar Khalil Mohamed Ahmed Luping Jiang +5 位作者 Fang Wang Song Chen Xueyan Zhou Xiaona Pei Xiyang Zhao Guanzheng Qu 《林业研究:英文版》 CAS CSCD 2020年第1期45-55,共11页
To determine appropriate quantities of water and fertilizer required for early growth of hybrid poplar cuttings,we recorded the growth traits of four clones grown under four factors(irrigation and nitrogen,phosphorus,... To determine appropriate quantities of water and fertilizer required for early growth of hybrid poplar cuttings,we recorded the growth traits of four clones grown under four factors(irrigation and nitrogen,phosphorus,and potassium fertilizers),each with four levels,using an orthogonal experimental design.A logistic model was used to estimate growth in height.The growth curves for tree height were sigmoid,and the model R^2 values were greater than 0.9,which indicated that the fit was highly significant.ANOVA results for tree height and basal diameter indicated that all sources of variance showed significant differences(p<0.001).The average tree height and basal diameter for all the four clones under the different treatments ranged from 155.39 to 235.04 cm,and from 13.71 to 17.42 mm,respectively.A highly positive correlation between the extreme k value and tree height was observed,suggesting that the k value was an accurate estimation of tree height.For model parameters,the earliest average time point for the onset of the rapid growth period of poplar clones was 131 d,and the highest average increment in tree height during the rapid growth period was 138.78 cm.The highest average tree height for all clones under each factor was 219,210.51,200,and 201 cm when treated with either 1200 mL of water applied every third day,3 g of nitrogen,0 g of phosphorus,or 0 g of potassium,respectively.The most suitable treatment for the early growth of hybrid poplar cuttings,as suggested by the developed logistic model,was 1200 mL of water applied every third day and three applications of 1 g nitrogen(in the form of CH4N2O). 展开更多
关键词 FERTILIZER management GROWTH TRAIT LOGISTIC model POPLAR RAPID GROWTH Variation
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Role of neurotrophic factors in enhancing linear axonal growth of ganglionic sensory neurons in vitro 预览
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作者 Michele Fornaro Alessia Giovannelli +4 位作者 Angelica Foggetti Luisa Muratori Stefano Geuna Giorgia Novajra Isabelle Perroteau 《中国神经再生研究:英文版》 SCIE CAS CSCD 2020年第9期1732-1739,共8页
Neurotrophins play a major role in the regulation of neuronal growth such as neurite sprouting or regeneration in response to nerve injuries. The role of nerve growth factor, neurotrophin-3, and brain-derived neurotro... Neurotrophins play a major role in the regulation of neuronal growth such as neurite sprouting or regeneration in response to nerve injuries. The role of nerve growth factor, neurotrophin-3, and brain-derived neurotrophic factor in maintaining the survival of peripheral neurons remains poorly understood. In regenerative medicine, different modalities have been investigated for the delivery of growth factors to the injured neurons, in search of a suitable system for clinical applications. This study was to investigate the influence of nerve growth factor, neurotrophin-3 and brain-derived neurotrophic factor on the growth of neurites using two in vitro models of dorsal root ganglia explants and dorsal root ganglia-derived primary cell dissociated cultures. Quantitative data showed that the total neurite length and tortuosity were differently influenced by trophic factors. Nerve growth factor and, indirectly, brain-derived neurotrophic factor stimulate the tortuous growth of sensory fibers and the formation of cell clusters. Neurotrophin-3, however, enhances neurite growth in terms of length and linearity allowing for a more organized and directed axonal elongation towards a peripheral target compared to the other growth factors. These findings could be of considerable importance for any clinical application of neurotrophic factors in peripheral nerve regeneration. Ethical approval was obtained from the Regione Piemonte Animal Ethics Committee ASLTO1(file # 864/2016-PR) on September 14, 2016. 展开更多
关键词 brain-derived neurotrophic factor DIRECTIONALITY dorsal root ganglia explant nerve growth factor nerve regeneration neurite growth enhancement neurotrophic factors NEUROTROPHIN-3 sensory neurons TORTUOSITY
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Vascular endothelial growth factor concentration in vitreous humor of patients with severe proliferative diabetic retinopathy after intravitreal injection of conbercept as an adjunctive therapy for vitrectomy
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作者 Bing Li Meng-Da Li +3 位作者 Jun-Jie Ye Zhe Chen Zi-Jian Guo Yu Di 《中华医学杂志:英文版》 SCIE CAS CSCD 2020年第6期664-669,共6页
Background:Proliferative diabetic retinopathy(PDR)is a progressive stage of diabetic retinopathy featured by the formation of neovascular and proliferative membrane.Vascular endothelial growth factor(VEGF)acts as a pi... Background:Proliferative diabetic retinopathy(PDR)is a progressive stage of diabetic retinopathy featured by the formation of neovascular and proliferative membrane.Vascular endothelial growth factor(VEGF)acts as a pivot factor in the development of neovascularization.This study was to investigate the changes of intravitreal VEGF concentrations of severe PDR after intravitreal injection of conbercept(IVC)and its potential advantages to the following vitrectomy.Methods:This was a prospective,interventional,randomized controlled study.Sixty eyes(60 patients)with severe PDR and 20 eyes from 20 patients with rhegmatogenous retinal detachment complicated with proliferative vitreoretinopathy were enrolled in this study.PDR eyes were randomly assigned to three groups by sortation randomization method with 20 eyes in each based on the interval of preoperative IVC(group A:7 days,group B:14 days,group C:non-IVC).Another 20 eyes without diabetes were enrolled as the non-diabetic control group(group D),receiving PPV directly.Vitreous specimens of all 80 patients were collected and evaluated afterwards.The intravitreal VEGF concentration of the four groups,and the total surgical time and the intraoperative bleeding rate of the PDR groups were recorded.Results:The mean intravitreal VEGF concentrations of groups A-D were 66.6±43.3,93.1±52.3,161.4±106.1 and 1.8±1.2 pg/mL,respectively.It increased significantly in PDR patients(groups A,B and C)(P=0.002,<0.001,and<0.001,respectively).PDR patients with preoperative IVC(groups A and B)presented significantly lower VEGF concentrations(P<0.001 and 0.001),intraoperative bleeding rates(P=0.004)and total surgical time(P<0.001,P=0.003)compared with group C.No statistical differences were presented between groups A and B on the three parameters.Conclusion:Seven days and 14 days of preoperative IVC are equally efficient and safe for the vitrectomy of severe PDR patients through decreasing vitreous VEGF concentrations,intraoperative bleeding rate and total surgical times. 展开更多
关键词 Anti-vascular endothelial growth factor Diabetic retinopathy/proliferative diabetic retinopathy Vitreous humor Vascular endothelial growth factor
Biological characteristics of dynamic expression of nerve regeneration related growth factors in dorsal root ganglia after peripheral nerve injury 预览
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作者 Yin-Ying Shen Xiao-Kun Gu +3 位作者 Rui-Rui Zhang Tian-Mei Qian Shi-Ying Li Sheng Yi 《中国神经再生研究:英文版》 SCIE CAS CSCD 2020年第8期1502-1509,共8页
The regenerative capacity of peripheral nerves is limited after nerve injury.A number of growth factors modulate many cellular behaviors,such as proliferation and migration,and may contribute to nerve repair and regen... The regenerative capacity of peripheral nerves is limited after nerve injury.A number of growth factors modulate many cellular behaviors,such as proliferation and migration,and may contribute to nerve repair and regeneration.Our previous study observed the dynamic changes of genes in L4–6 dorsal root ganglion after rat sciatic nerve crush using transcriptome sequencing.Our current study focused on upstream growth factors and found that a total of 19 upstream growth factors were dysregulated in dorsal root ganglions at 3,9 hours,1,4,or 7 days after nerve crush,compared with the 0 hour control.Thirty-six rat models of sciatic nerve crush injury were prepared as described previously.Then,they were divided into six groups to measure the expression changes of representative genes at 0,3,9 hours,1,4 or 7 days post crush.Our current study measured the expression levels of representative upstream growth factors,including nerve growth factor,brain-derived neurotrophic factor,fibroblast growth factor 2 and amphiregulin genes,and explored critical signaling pathways and biological process through bioinformatic analysis.Our data revealed that many of these dysregulated upstream growth factors,including nerve growth factor,brain-derived neurotrophic factor,fibroblast growth factor 2 and amphiregulin,participated in tissue remodeling and axon growth-related biological processes Therefore,the experiment described the expression pattern of upstream growth factors in the dorsal root ganglia after peripheral nerve injury.Bioinformatic analysis revealed growth factors that may promote repair and regeneration of damaged peripheral nerves.All animal surgery procedures were performed in accordance with Institutional Animal Care Guidelines of Nantong University and ethically approved by the Administration Committee of Experimental Animals,China(approval No.20170302-017)on March 2,2017. 展开更多
关键词 axon GROWTH bioinformatic ANALYSIS dorsal root ganglia GROWTH factors INGENUITY Pathway ANALYSIS NERVE regeneration peripheral NERVE INJURY rat SCIATIC NERVE crush INJURY transcriptome sequencing upstream regulators
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Growth Performance, Undergrowth Diversity and Carbon Sequestration Potentials of Tree Species Stand Combinations, Ghana 预览
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作者 Samuel Novor Simon Abugre 《林学期刊(英文)》 2020年第1期135-154,共20页
The limited number of studies on mixed plantations makes it difficult to accurately predict success of mixed-species combination especially with regards to growth, undergrowth diversity and carbon sequestration potent... The limited number of studies on mixed plantations makes it difficult to accurately predict success of mixed-species combination especially with regards to growth, undergrowth diversity and carbon sequestration potentials. This study therefore provides information on the effects of Ceiba pentandra, Terminalia superba, Cedrela odorata and Khaya anthotheca in three different stand combinations on growth, undergrowth diversity and carbon sequestration potential. A 15-year-old coupe of 32 ha of mixed tree species stand combinations was selected for the study. The coupe was stratified based on the species combinations. Nested sub-plots (25 m × 25 m) were randomly laid in different species stand combinations for growth data collection. In each nested sub-plot, 1 m × 1 m plots were also randomly laid for undergrowth diversity study. The results revealed that two species stand combination of Ceiba pentandra and Terminalia superba performed better in terms of growth, carbon sequestration and carbon content as compared to the other species stand combinations. The saplings on the other hand, were more diverse under the three species stand combination plots. Also, the effective number of species, species richness, evenness, and dominance were higher in the four species stand combination plots. Generally, Ceiba pentandra and Terminalia superba are compatible as it produced the highest growth and carbon sequestration potential. 展开更多
关键词 Species Combination Growth FLORISTIC Composition Carbon Content SAPLINGS
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Elevated VEGF-A & PLGF concentration in aqueous humor of patients with uveal melanoma following Iodine-125 plaque radiotherapy
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作者 Meng-Xi Chen Yue-Ming Liu +2 位作者 Yang Li Xuan Yang Wen-Bin Wei 《国际眼科杂志:英文版》 SCIE CAS 2020年第4期599-605,共7页
AIM: To measure the concentration of vascular endothelial growth factor-A(VEGF-A), and placental growth factor(PLGF) in aqueous humor of uveal melanoma patients before and after Iodine-125 plaque therapy(IPT), determi... AIM: To measure the concentration of vascular endothelial growth factor-A(VEGF-A), and placental growth factor(PLGF) in aqueous humor of uveal melanoma patients before and after Iodine-125 plaque therapy(IPT), determine the postoperative fluctuation and evaluate associated factors in vivo.METHODS: Participants were 18 Chinese patients with uveal melanoma who were elected to IPT. Undiluted aqueous humor samples were collected at Iodine plaque implant and removal time, then stored immediately at-80℃ until assayed. The concentration of VEGF-A, PLGF and other 7 cytokines comprising interleukin-2(IL-2), IL-8, IL-10, interferon(IFN)-γ, programmed death(PD)-1, transforming growth factor(TGF)-β1 and insulin-like growth factor(IGF)-1 in aqueous humor was measured using Raybiotech immunoassay kit, a high throughput strategy. The VEGF-A and PLGF levels were compared across preoperation and postoperation subgroups, as well as those of other 7 interleukins. Correlation and grouped analyses were conducted to determine the independent effects of clinical parameters and other cytokines on VEGF-A and PLGF concentration or fluctuation. This study set a self-control design.RESULTS: VEGF-A(P=0.038) and PLGF(P=0.026) were the only two increased cytokines after IPT. Preoperative and postoperative level of VEGF-A and PLGF(r=0.575, P=0.013;r=0.987, P<0.001) correlated with each other significantly. Level of VEGF-A(r=0.626, P=0.005;r=0.588, P=0.01) and PLGF(r=0.616, P=0.007;r=0.588, P=0.01) had positive correlation with tumor thickness consistently. Elevated VEGF-A or PLGF level were strong predictive factors of each other(P=0.007, OR=60.0). The elevated VEGF-A group showed a higher postoperative level of IFN-γ(P=0.005), IL-2(P<0.001) and IL-10(P=0.004) in aqueous humor. When the elevated PLGF group got similar results that a higher postoperative level of IFN-γ(P=0.007), IL-2(P<0.001) and IL-10(P=0.013) in aqueous humor. CONCLUSION: This study reveals that VEGF-A and PLGF in aqueous humor significantly increased with tumor thicknes 展开更多
关键词 uveal melanoma vascular endothelial growth factor-A radioplaque therapy placental growth factor
铝胁迫下一氧化氮对巨尾桉生长及生理的影响 预览
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作者 罗文姬 罗必敬 +2 位作者 蒋霞 侯文娟 王凌晖 《热带作物学报》 CSCD 北大核心 2020年第1期77-82,共6页
酸铝抑制植物生长是全球关注的热点。以往关于酸铝胁迫的研究主要在禾本科和豆科植物上,而对经济用材林木较少。为此,本研究以巨尾桉广林9号为供试材料,在无铝(0 mmol/L)和铝胁迫(5 mmol/L)2种情况下,设置一氧化氮(NO)3个水平(0、10、50... 酸铝抑制植物生长是全球关注的热点。以往关于酸铝胁迫的研究主要在禾本科和豆科植物上,而对经济用材林木较少。为此,本研究以巨尾桉广林9号为供试材料,在无铝(0 mmol/L)和铝胁迫(5 mmol/L)2种情况下,设置一氧化氮(NO)3个水平(0、10、500μmol/L),以期探究铝胁迫下外源施加NO对巨尾桉生长和生理方面的影响。试验结果表明:(1)5 mmol/L铝处理下的巨尾桉根、茎、叶生物量分别显著减少了11.57%、12.04%和37.37%,叶片叶绿素a、叶绿素a+b和类胡萝卜素含量积累也受抑制;(2)铝胁迫下叶片细胞膜透性显著增大,膜脂过氧化的产物丙二醛(MDA)显著增加了43.12%,细胞可溶性糖和蛋白含量分别显著减少了9.43%、42.27%;(3)适量添加NO(10μmol/L)可提高铝胁迫下光合色素含量,提高最大的叶绿素a达41.23%,MDA含量明显降低了27.66%,提高可溶性糖和可溶性蛋白含量,以达到调节活性氧代谢来维持细胞膜结构稳定的效果,从而使生物量显著提高了10.19%;(4)NO浓度过高(500μmol/L SNP)时反而对巨尾桉有毒害作用,生物量下降了15.17%,说明NO具有双重性。综上所述,铝胁迫对巨尾桉生长、渗透调节物质和抗氧化酶等生理特性均产生了抑制作用,而适当添加外源NO可以缓解铝对巨尾桉的毒害作用。 展开更多
关键词 巨尾桉 铝胁迫 一氧化氮 生长 生理
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宁夏扬黄灌区有机肥配施氮肥对滴灌春玉米生长和产量的影响
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作者 王艳丽 吴鹏年 +2 位作者 王西娜 李培富 朱旭 《玉米科学》 CAS CSCD 北大核心 2020年第1期151-159,共9页
通过两年田间定位试验,采用裂区设计,设有机肥为主处理,氮肥为副处理,研究滴灌条件下有机肥与氮肥配施对玉米生长和产量的影响,滴灌条件下砂质土壤春玉米田有机肥和氮肥配施的最佳施用量,为土壤培肥、化肥减施以及提高宁夏扬黄灌区玉米... 通过两年田间定位试验,采用裂区设计,设有机肥为主处理,氮肥为副处理,研究滴灌条件下有机肥与氮肥配施对玉米生长和产量的影响,滴灌条件下砂质土壤春玉米田有机肥和氮肥配施的最佳施用量,为土壤培肥、化肥减施以及提高宁夏扬黄灌区玉米产量提供理论依据。结果表明,玉米产量以有机肥3 000 kg/hm~2配施300 kg/hm~2氮肥处理最高,比不施肥处理增产50.65%;其次为有机肥4 500 kg/hm~2配施300 kg/hm~2氮肥和有机肥4 500 kg/hm~2配施225 kg/hm~2氮肥处理,分别较不施肥增产48.78%和46.83%。根据宁夏中部干旱带扬黄灌区土壤培肥和玉米增产需要,建议推荐有机肥施用量为3 000~4 500 kg/hm~2,配施氮肥用量225~300 kg/hm~2。 展开更多
关键词 玉米 有机肥 氮肥 生长 产量
Mechanism and mitigation of spontaneous Ga whisker growth on Cr2GaC
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作者 ZHANG PeiGen DING JianXiang +5 位作者 LIU YuShuang YANG Li TIAN WuBian OUYANG Jian ZHANG YaMei SUN ZhengMing 《中国科学:技术科学英文版》 SCIE EI CAS CSCD 2020年第3期440-445,共6页
Spontaneous growth of A-element whiskers on Mn+1AXn(MAX for short) phase materials poses a barrier to their practical applications, since it casts doubts on their stability. In this study, Ga whisker growth on sintere... Spontaneous growth of A-element whiskers on Mn+1AXn(MAX for short) phase materials poses a barrier to their practical applications, since it casts doubts on their stability. In this study, Ga whisker growth on sintered Cr2GaC samples was investigated. The elemental source for spontaneous growth of Ga whiskers is identified as the free Ga contained in the Cr2GaC material, not the lattice atoms from Cr2GaC grains, which removes the doubts on the stability of Cr2GaC material. The growth behavior and morphologies of the Ga whiskers follow a new catalysis-based model, with cleavage planes of Cr2GaC grains involved as nucleation sites. This model explains and predicts well the growth behavior of the whiskers. The mitigation strategy based on this model is in principle simple: to prevent free Ga in Cr2GaC material or limit it to a certain level;to avoid cleavage plane of Cr2GaC grains;to achieve high density of the Cr2GaC material. 展开更多
关键词 MAX phase whisker growth nucleation model mitigation strategy
中国九市七岁以下儿童生长迟缓状况调查研究
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作者 张亚钦 李辉 +10 位作者 武华红 宗心南 李一辰 李佳 相晓妹 张晶 童梅玲 曹中强 林穗方 陈为 朱克 《中华儿科杂志》 CAS CSCD 北大核心 2020年第3期194-198,199,200,共7页
目的调查分析中国9个城市(简称九市)7岁以下儿童生长迟缓的发生情况。方法采用分层整群抽样方法,于2016年6—11月在北京、哈尔滨、西安(北片),上海、南京、武汉(中片),广州、福州、昆明(南片)九市对7岁以下的110499名儿童体格生长情况... 目的调查分析中国9个城市(简称九市)7岁以下儿童生长迟缓的发生情况。方法采用分层整群抽样方法,于2016年6—11月在北京、哈尔滨、西安(北片),上海、南京、武汉(中片),广州、福州、昆明(南片)九市对7岁以下的110499名儿童体格生长情况进行横断面调查。以2009年中国儿童生长标准为参照,身高低于同性别同年龄身高标准第3百分位判定为生长迟缓,位于第3~10百分位判定为身高偏矮。检出率按性别、地区、年龄等分组,组间生长迟缓检出率比较采用χ2检验。结果九市7岁以下儿童应调查113084名,实际调查110499名,调查率97.7%。生长迟缓总检出率为1.9%(2141/110499);城区低于郊区[1.6%(904/55524)比2.3%(1237/54975),χ2=56.246,P<0.01];男、女差异无统计学意义[1.9%(1121/57921)比1.9%(1020/52578),χ2=0.003,P=0.965];生长迟缓检出率在0~<3岁随年龄略下降[从0~<1岁组1.8%(312/17080)至2~<3岁组1.2%(168/13740)],之后略提高,6~<7岁为2.2%(240/11073)。不同地区比较,南片高于北、中片[城区3.3%(557/16664)比0.9%(193/20374)、0.8%(154/18486),郊区4.7%(769/16276)比1.1%(241/21924)、1.4%(227/16775),χ2=437.736、646.533,P均<0.01];而城区北、中片差异无统计学意义(χ2=1.429,P=0.232),郊区中片略高于北片(χ2=5.130,P=0.024)。九市中广州市生长迟缓率最高(6.1%,613/10019),各城市比较差异有统计学意义(χ2=1559.64,P<0.01)。生长迟缓程度构成显示以临界和轻度为主(78.4%,1679/2141),重度较少(7.2%,154/2141)。身高偏矮儿童检出率为5.2%(5721/110499)。结论九市7岁以下儿童生长迟缓处于较低流行状态,且检出生长迟缓儿童多为轻度。生长迟缓检出率郊区高于城区,男女差别不明显,南片地区高于北、中片地区。 展开更多
关键词 儿童 生长 生长迟缓 检出率
光照对唐娜彩叶凤梨生长和叶片营养的影响 预览
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作者 李萍 杨庆华 《现代农业科技》 2020年第2期110-112,119,共4页
彩叶凤梨属植物是凤梨科中一个以观叶为主的类群,株型饱满、叶片宽短且叶色鲜艳为其主要观赏特征,而光照条件对上述性状起着十分关键的作用。本试验以唐娜彩叶凤梨为研究对象,设置A(夏季最高光强4万~5万lx)、B(最大光强1.6万~1.8万lx)... 彩叶凤梨属植物是凤梨科中一个以观叶为主的类群,株型饱满、叶片宽短且叶色鲜艳为其主要观赏特征,而光照条件对上述性状起着十分关键的作用。本试验以唐娜彩叶凤梨为研究对象,设置A(夏季最高光强4万~5万lx)、B(最大光强1.6万~1.8万lx)、C(最大光强6 000~8 000 lx)3种不同光照强度处理4个月后,观测植株的生长、生物量、营养元素和光合色素的变化。结果表明,处理A植株生长最佳,表现为叶片数量多、株型紧凑、叶片宽短;研究还发现,植物可通过调整根冠比、体内光合色素的含量以及增加体内游离氨基酸等小分子物质的浓度来适应高光强,从而提高植物的光合作用,促进植物生长。 展开更多
关键词 唐娜彩叶凤梨 光照强度 生长发育 营养元素
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周期性饥饿再投喂对长蛸存活、生长以及肌肉脂肪酸和氨基酸的影响 预览
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作者 宋旻鹏 汪金海 +2 位作者 陈智威 李希豹 郑小东 《水生生物学报》 CAS CSCD 北大核心 2020年第2期372-378,共7页
在19.8—22.2℃条件下,采用周期性饥饿再投喂的方法,研究不同投喂模式对长蛸[Octopus minor,初始体重(94.29±9.35)g,初始胴背长(53.25±5.25)mm]的存活、生长以及脂肪酸和氨基酸的影响。实验分为4个组包括对照组(持续投喂)、S... 在19.8—22.2℃条件下,采用周期性饥饿再投喂的方法,研究不同投喂模式对长蛸[Octopus minor,初始体重(94.29±9.35)g,初始胴背长(53.25±5.25)mm]的存活、生长以及脂肪酸和氨基酸的影响。实验分为4个组包括对照组(持续投喂)、S1F5组(周期性饥饿1d再投喂5d)、S2F4组(周期性饥饿2d再投喂4d)和S3F3组(周期性饥饿3d再投喂3d),持续24d。实验结果如下:随饥饿时间的延长,增重率、肝体比、体重变化量以及终末体重四个指标均呈现出先上升后下降的趋势,其中S1F5组的值均显著高于对照组,而S3F3组的值除肝体比外均显著低于对照组。长蛸的成活率随饥饿时间的增长呈现出下降趋势,但各实验组均与对照组差异不显著;摄食量随饥饿时间的延长,表现出上升趋势,且三个实验组的值均显著高于对照组。在长蛸肌肉脂肪酸中,饱和脂肪酸(SFA)、不饱和脂肪酸(UFA)、单不饱和脂肪酸(MUFA)以及多不饱和脂肪酸(PUFA)的含量均与对照组差异不显著,但S1F5组的值与对照组相比出现了一定程度的升高;在氨基酸含量上,各实验组的必需氨基酸总量(TEAA)、氨基酸总量(TAA)以及必需氨基酸总量/氨基酸总量(TEAA/TAA)的值均与对照组差异不显著。综上所述,S1F5组和S2F4组长蛸出现了补偿生长现象,且S1F5组长蛸具备超补偿生长能力。因此,在长蛸的人工养殖过程中,为保证其养殖效果,建议采用周期性饥饿1d再投喂5d的投喂模式。 展开更多
关键词 长蛸 饥饿再投喂 存活 生长 脂肪酸 氨基酸
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西北太平洋北方拟黵乌贼耳石外部形态特性分析 预览
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作者 任品 陆化杰 +4 位作者 唐悦 宁欣 刘凯 陈子越 陈新军 《水产学报》 CAS CSCD 北大核心 2020年第1期49-60,共12页
根据2018年9-11月我国鱿钓船在西北太平洋采集的339尾北方拟黵乌贼样本,对其耳石外形生长特征进行了研究。结果发现,北方拟黵乌贼具有长窄的吻区和宽大的翼区。主成分分析表明,耳石总长(TSL)、吻侧区长(RLL)、侧区长(LDL)、翼区长(WL)... 根据2018年9-11月我国鱿钓船在西北太平洋采集的339尾北方拟黵乌贼样本,对其耳石外形生长特征进行了研究。结果发现,北方拟黵乌贼具有长窄的吻区和宽大的翼区。主成分分析表明,耳石总长(TSL)、吻侧区长(RLL)、侧区长(LDL)、翼区长(WL)和最大宽度(MW)可以作为北方拟黵乌贼耳石外形变化的特征因子。协方差分析表明,MW、LDL和WL与胴长的关系存在性别间显著性差异,TSL和RLL则不存在显著性差异;MW、RLL、TSL、LDL和WL与体质量的关系均存在性别间显著性差异。AIC(Akaike’s information criterion)分析表明,TSL、RLL与胴长的生长关系最适合用线性函数表示,雄性个体的MW、LDL和雌雄个体的WL与胴长的关系最适合用幂函数表示,而雌性个体的LDL则最适合用指数函数表示。雄性个体的LDL和MW与体质量的关系最适合用指数函数表示,雌性个体的LDL、MW和TSL最适合用线性函数表示,而其余特征参数则均最适合用幂函数表示。随着胴长增加,耳石绝对尺寸都逐渐增大,但耳石的形态结构比例基本不变:背区、侧区、吻侧区、翼区的长度与耳石总长之比基本保持一致,分别为35.66%、55.84%、75.23%和85.82%左右。 展开更多
关键词 北方拟黵乌贼 耳石形态特征 生长特性 西北太平洋
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继续教育专职班主任队伍建设的探索与实践——以浙江大学继续教育学院为例 预览
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作者 周晶 朱再法 《继续教育研究》 2020年第2期9-12,共4页
通过对班主任队伍的组织架构、管理模式、培养方法进行调查分析,为建设一支规范化、专业化、精细化的班主任队伍提供理论支撑,并对存在的问题提供解决方案与建议。文章以浙江大学继续教育学院的班主任队伍为样本,通过对继续教育学院班... 通过对班主任队伍的组织架构、管理模式、培养方法进行调查分析,为建设一支规范化、专业化、精细化的班主任队伍提供理论支撑,并对存在的问题提供解决方案与建议。文章以浙江大学继续教育学院的班主任队伍为样本,通过对继续教育学院班主任、培训学员、任课教师及关联部门的问卷调查,广泛搜集信息、资料和建议。通过研究分析,建议进一步提高对班主任工作重要性的认识,提高站位,明确角色定位,理清工作边界,对班主任进行统一管理,分层级培养,通过合理有效的激励机制,推进班主任队伍高质量建设。 展开更多
关键词 继续教育 班主任 模式 稳定 成长
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微生态制剂在葡萄上的促生防病效果 预览
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作者 善文辉 胡海瑶 +6 位作者 王红丽 王金娥 汪海霞 袁云刚 赵强 张文波 王琦 《果树学报》 CAS CSCD 北大核心 2020年第3期404-410,共7页
【目的】明确微生态制剂绿康威和绿地康对葡萄的田间促生防病效果,为实现葡萄的安全高效生产提供依据。【方法】在包头市以‘巨峰’和‘寒香蜜’葡萄为材料,比较微生态制剂和杀菌剂单独或交替使用的5个处理在生长量、产量和果实品质、... 【目的】明确微生态制剂绿康威和绿地康对葡萄的田间促生防病效果,为实现葡萄的安全高效生产提供依据。【方法】在包头市以‘巨峰’和‘寒香蜜’葡萄为材料,比较微生态制剂和杀菌剂单独或交替使用的5个处理在生长量、产量和果实品质、对霜霉病的防效上的差别。【结果】微生态制剂的使用能显著促进‘巨峰’和‘寒香蜜’茎粗、茎长的生长,提高叶片叶绿素含量,同时增加产量和百粒质量,而对叶长、叶宽的影响不稳定,对可溶性固形物含量无影响。生长季在地上部和地下部同时使用绿康威和绿地康7次,对‘巨峰’葡萄的霜霉病防效最好,可达75.68%;而田间常规用药防效仅为38.74%,单独地下部施用绿地康的防效为57.66%。【结论】地上部和地下部同时使用微生态制剂对葡萄促生长和霜霉病绿色防控有良好效果。 展开更多
关键词 葡萄 微生态制剂 生长量 葡萄霜霉病 产量
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黑点青鳉的生长和摄食行为发育 预览
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作者 陈剑明 陈雅飞 +2 位作者 徐永健 宁燕 戴铃灵 《水产学报》 CAS CSCD 北大核心 2020年第1期71-78,共8页
针对黑点青鳉实验室养殖成活率低的问题,对其摄食行为发育进行研究,了解其早期阶段的摄食行为发育状况,为人工养殖提供理论依据。通过单摄像机结合镜面成像的方法,对黑点青鳉胚后发育阶段90 d摄食行为的观察与分析,研究了投喂卤虫无节... 针对黑点青鳉实验室养殖成活率低的问题,对其摄食行为发育进行研究,了解其早期阶段的摄食行为发育状况,为人工养殖提供理论依据。通过单摄像机结合镜面成像的方法,对黑点青鳉胚后发育阶段90 d摄食行为的观察与分析,研究了投喂卤虫无节幼体条件下黑点青鳉的生长特征和摄食行为发育。结果显示,幼体体长平均生长率为2.579%/d,体长与日龄间关系为y=3.132+0.383x-0.004x~2+0.00003x~3,R~2=0.98。通过各项摄食行为指标将其幼体生长发育分为3期6个阶段:仔鱼期(0~10 d)分为前仔鱼期(0~4 d)和后仔鱼期(5~10 d),稚鱼期(11~30 d)分为前稚鱼期(11~18 d)、中稚鱼期(19~24 d)和后稚鱼期(25~30 d),幼鱼期(31~65 d)。黑点青鳉幼体出膜4 d后开始投喂初孵卤虫,至10 d所有鱼苗均能捕食。黑点青鳉仔鱼期幼体死亡率较高,但摄食能力稳步提升,至该期末,摄食成功率提升至45%~55%,摄食效率达0.5~0.6个/min;稚鱼期幼体的各项摄食指标均有大幅度提升,对饵料的响应时间不断缩短,摄食速率提高,响应距离也逐渐增长,摄食量增大,摄食成功率已提升至90%~95%;幼鱼期各项摄食指标已接近成鱼,摄食效率达9个/min以上,摄食功能已趋于完善。研究表明,黑点青鳉在仔鱼期对卤虫无节幼体的响应距离短、摄食速率低下,摄食成功率与摄食效率均处于较低水平,随着其自身的发育以及摄食能力的稳定提升,摄食成功率和摄食效率逐步提高,成活率趋于稳定。养殖期间,通过密切注意黑点青鳉的摄食行为变化,改变投喂的数量和频次,使更多的仔鱼尽快过渡到稚鱼期,可能是提高养殖成活率的一条有效途径。 展开更多
关键词 黑点青鳉 仔稚鱼期 生长 摄食行为 发育 生态毒理学
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麻地膜对设施樱桃番茄(Solanum lycopersivon)生长及产量的影响
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作者 安霞 金关荣 +6 位作者 李鲁峰 李文略 骆霞虹 陈常理 朱关林 楼旭平 许亚俊 《分子植物育种》 CAS CSCD 北大核心 2020年第3期1034-1038,共5页
为了明确麻地膜覆盖在设施大棚内对樱桃番茄生长及产量的影响,本研究采用‘浙樱粉1号’为实验材料,设置3个处理:麻地膜覆盖、塑料地膜覆盖及对照(不覆盖),比较了不同覆盖措施对‘浙樱粉1号’株高、茎粗、单株鲜重、结果数量及樱桃番茄... 为了明确麻地膜覆盖在设施大棚内对樱桃番茄生长及产量的影响,本研究采用‘浙樱粉1号’为实验材料,设置3个处理:麻地膜覆盖、塑料地膜覆盖及对照(不覆盖),比较了不同覆盖措施对‘浙樱粉1号’株高、茎粗、单株鲜重、结果数量及樱桃番茄鲜果重的影响。结果表明,在设施大棚内采用麻地膜覆盖增加了‘浙樱粉1号’株高、茎粗、结果数量及樱桃番茄鲜果重。麻地膜覆盖对设施大棚内种植的樱桃番茄有增产作用,麻地膜的推广应用可以减少塑料地膜对环境污染,利于农业的可持续发展。 展开更多
关键词 麻地膜 樱桃番茄(Solanum lycopersivon) 生长 产量
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