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2020 2

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NPY 1

产后服务 1

剖宫产术后 1

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大菱鲆 1

差异表达 1

扫描探针显微镜 1

投喂 1

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肠道生理 1

育龄妇女 1

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Postnatal feeding with high-fat diet induces obesity and precocious puberty in C57BL/6J mouse pups: a

null

《医学前沿（英文）》 2017年第11卷第2期页码 266-276 doi: 10.1007/s11684-017-0530-y

摘要：

Childhood obesity and obesity-related metabolic complications are induced by a high-fat postnatal diet. The lack of a suitable animal model, however, remains a considerable challenge in obesity studies. In the current study, we provided high-fat diet (HFD) to dams during lactation and to pups after weaning. We also developed a novel model of C57BL/6J mouse pups with HFD-induced postnatal obesity. Results showed that feeding with HFD induces fat deposition and obesity in pups. Furthermore, HFD more potently increased the body weight (BW) of male than female pups. HFD-fed female pups were obese, underwent precocious puberty, and showed increased kisspeptin expression in the hypothalamus. However, parental obesity and precocious puberty exerted no synergistic effects on the HFD-induced postnatal weight gain and puberty onset of the pups. Interestingly, some HFD-fed litters with normal BW also exhibited precocious puberty. This finding suggested that diet composition but not BW triggers puberty onset. Our model suggests good construction validity of obesity and precocious puberty. Furthermore, our model can also be used to explore the mutual interactions between diet–induced postnatal childhood obesity and puberty.

关键词： postnatal HFD feeding obesity kisspeptin HPG axis precocious puberty

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Influence of glucose feeding on the ligninolytic enzyme production of the white-rot fungus Phanerochaete

ZHOU Xiaoyan, WEN Xianghua, FENG Yan

《环境科学与工程前沿（英文）》 2007年第1卷第1期页码 89-94 doi: 10.1007/s11783-007-0017-1

摘要： The present work studied the influence of glucose feeding on the ligninolytic enzyme production of in a nitrogen-limited (C/N ratio is 56/8.8 mmol/L) medium. Several sets of shaking flask experiments were conducted. The results showed that 2 g/L glucose feeding on the first day of the culture (24 h after the inoculation) stimulated both fungal biomass growth and enzyme production. The manganese peroxidase (MnP) activity was 2.5 times greater than that produced in cultures without glucose feeding. Furthermore, the glucose feeding mode in fed-batch culture was also investigated. Compared to cultures with glucose feeding every 48 h, cultures with glucose feeding of 1.5 g/L (final concentration) every 24 h produced more enzymes. The peak and total yield of MnP activity were 2.7 and 3 times greater compared to the contrast culture, respectively, and the enzyme was kept stable for 4 days with an activity of over 200 U/L.

关键词： enzyme production fed-batch culture nitrogen-limited inoculation mmol/L

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Sustainable intensification of agriculture is key to feeding Africa in the 21st century

Shenggen FAN

《农业科学与工程前沿（英文）》 2020年第7卷第4期页码 366-370 doi: 10.15302/J-FASE-2020342

摘要：

Africa in facing numerous challenges in the 21st century in feeding its rapidly increasing population. Land resources have become limited due to urbanization and industrialization. The existing agricultural land has been degraded and soil fertility has declined due to unsustainable farming practices. Despite of progress made in the past several decades, hunger and malnutrition in Africa still hinder health, human development and economic growth, which will become even worse in the future if proper measures are not taken. Sustainable intensification is the only solution to tackling both environmental sustainability including climate change and malnutrition, i.e., to produce more foods in terms of nutrients human body needs with less natural resources and carbon emissions. To achieve this vision, innovations in technologies, policies and institutions are essential. The Chinese experience in Agricultural Green Development (AGD) can be shared with Africans when the region is pursuing its sustainable intensification strategy.

关键词： Africa sustainable intensification Agricultural Green Development climate change malnutrition

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以喂养方式视角浅析新时期城市基层计生优质服务

严小青

《中国工程科学》 2014年第16卷第5期页码 24-30

摘要：

通过选取杭州市上城区社区卫生院109 例婴儿及其母亲为调查对象，利用SPSS18.0 软件分别从一般参考量、影响喂养方式相关性因素以及基层计生优质服务需求进行数据统计分析，从而得到影响母乳喂养因素、喂养方式与婴儿体格关系以及服务需求重点，从而提出要从卫生计生联手、育医结合，立足基层架构群众满意服务网络；探索途径、优化服务，实现流动人口优质服务一盘棋；强化队伍、创新机制，探索建立科学规范服务考核评估体系三方面全面提升新时期基层计生优质服务水平。

关键词：喂养方式统计分析计生优质服务

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HEMIPTERAN-TRANSMITTED PLANT VIRUSES: RESEARCH PROGRESS AND CONTROL STRATEGIES

《农业科学与工程前沿（英文）》 2022年第9卷第1期页码 98-109 doi: 10.15302/J-FASE-2021389

摘要：

About 80% of plant viruses are transmitted by specific insect vectors, especially hemipterans with piercing-sucking mouthparts. Many virus-transmitting insects are also important crop pests that cause considerable losses in crop production. This review summarizes the latest research findings on the interactions between plant viruses and insect vectors and analyzes the key factors affecting insect transmission of plant viruses from the perspectives of insect immunity, insect feeding, and insect symbiotic microorganisms. Additionally, by referring to the latest applications for blocking the transmission of animal viruses, potential control strategies to prevent the transmission of insect-vectored plant viruses using RNAi technology, gene editing technology, and CRISPR/Cas9+ gene-driven technology are discussed.

关键词： control strategies / feeding / immunity / insect vector / microorganism / plant virus

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大菱鲆神经肽Y基因克隆及其在工厂化养殖饥饿-投喂策略中的表达特征分析

韩建,刘滨,姜志强,穆小生,雷霁霖

《中国工程科学》 2014年第16卷第9期页码 42-49

摘要：

本文通过逆转录聚合酶链式反应（RT-PCR）和末端快速扩增技术（RACE）克隆了大菱鲆神经肽Y（NPY）基因全长为729 bp 的互补脱氧核糖核酸（cDNA）序列，其中5′非翻译区（5′-UTR）为70 bp，3′非翻译区（3′-UTR）为359 bp，开放阅读框（ORF）为300 bp。ORF编码含有99 个氨基酸的蛋白质多肽，N端28 个氨基酸为信号肽，信号肽后是由36 个氨基酸组成的NPY成熟肽。针对大菱鲆NPY蛋白质与其他物种的同源性进行比较，结果显示大菱鲆NPY与其他物种的同源性在53.9 %~98 %，特别是与同属于鲆鲽鱼类的牙鲆和美洲拟鲽的同源性高达97 %~98 %，表现出很高的保守性。采用实时定量PCR对大菱鲆NPY基因的表达特征进行分析，结果表明，大菱鲆NPY基因在神经组织和外围组织中都有表达，其中在下丘脑中的表达量最高。饥饿实验中，随着饥饿的进行，NPY的表达量显著变化（P<0.05），呈现先升高再降低，再显著升高并维持一段高水平表达后，再次下降的趋势，饥饿后再投喂会使NPY的表达量升高，并且饥饿时间越长，再投喂后NPY的表达水平越高，但是再投喂2 h 后表达量还会再次下降至相似的水平，这都预示着NPY是一种摄食刺激因子，并且是一种短期的调控机制。

关键词：大菱鲆 NPY 饥饿投喂差异表达

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北京市剖宫产育龄妇女产后避孕意愿分析

沈洁,高丽丽,潘迎

《中国工程科学》 2014年第16卷第5期页码 16-19

摘要：

为了了解北京市剖宫产术后妇女的避孕意愿及其影响因素，在北京市城、近、郊区采用分层整群抽样方法随机抽取2011 年7 月—2011 年12 月期间接受剖宫产手术的产妇364 名，进行问卷调查。采用卡方检验和多因素Logistic 回归方法对问卷调查结果进行分析。结果显示，被调查妇女平均年龄为（31±4.53）岁，剖宫产术后计划恢复性生活时间中位数为7 周。96.43 %的妇女对于产后可以采用的避孕方法并不清楚。仅有27.74 %的妇女表示产后会尽早或立即采取避孕措施，避孕套是妇女首选的产后避孕方法，占75.27 %。72.25 %的妇女没有避孕计划或要等到产后3 个月才开始避孕。62.64 %的妇女在剖宫产术后接受了避孕指导，医生推荐的产后避孕方法中避孕套占首位。医生强调剖宫产术后避孕的重要性、妇女具备正确产后避孕知识是妇女剖宫产术后尽早开始避孕的保护因素。剖宫产妇女对产后避孕服务有较高需求，希望在产前保健或产后访视时能得到专业人员的产后避孕咨询指导。剖宫产术后再次妊娠存在健康风险，剖宫产妇女产后尽早落实避孕措施应引起高度关注。建议尽快针对剖宫产妇女开展产后避孕服务，摸索适合北京的服务模式，以满足需求，减少产后非意愿妊娠的发生，降低剖宫产术后人工流产的风险。

关键词：育龄妇女剖宫产术后产后服务避孕

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Developmental expression of CAPON and Dexras1 in spinal cord of rats

LI Xin, CHENG Chun, CHEN Mengling, GAO Shangfeng, ZHAO Jian, NIU Shuqiong, SHEN Aiguo

《医学前沿（英文）》 2008年第2卷第1期页码 75-81 doi: 10.1007/s11684-008-0014-1

摘要： To study the expression of the carboxy-terminal PSD-95/DLG/ZO-1 ligand of nNOS (CAPON) and Dexras1 mRNA during development in the spinal cord of rats, real-time polymerase chain reaction (Real-time PCR), as a quantitative method, was used to study the developmental expression of CAPON and Dexras1 mRNA level in the spinal cord. The spatial expression of CAPON and Dexras1 mRNA was examined by a combination of hybridization (ISH) and immunofluorescence. During the development of the spinal cord, CAPON mRNA was expressed in low levels from embryo day 14 to day 18. At postnatal day 1, it reached the peak and was expressed in the part which will become the dorsal horn when mature. It then decreased gradually until postnatal week 12, when it presented in the ventral horn. At embryo day 14, Dexras1 mRNA was expressed at low levels, increased during embryo day 16 to day 18 and peaked at postnatal day 1. Spatiotemporal expression of Dexras1 mRNA was similar to CAPON as confirmed by correlation analysis and colocalization. CAPON and neuronal nitric oxide synthase (nNOS) was expressed within the same cells of the dorsal horn at postnatal day 1 but had different subcellular localizations. Co-expression of CAPON and Dexras1 mRNA in myeloid tissue during development process of rat indicates that the adaptor protein, CAPON may play a probable role in differentiation of neurons, synaptic plasticity and synaptogenesis by regulating nNOS to activate Dexras1.

关键词： CAPON ISH differentiation postnatal different subcellular

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大面积扫描探针显微镜研制

路小波,陆祖宏,周庆,王国著

《中国工程科学》 2004年第6卷第9期页码 50-55

摘要：

介绍了一种大面积扫描探针显微镜。仪器采用大范围扫描与高精度微动扫描相分离、X-Y扫描与纵向检测相分离的方案，同时具备较大扫描范围和较高的分辨率，扫描重复性好，大面积扫描范围220mm×290mm×60mm，重复性2～3 μm，并可实现探针的自动逼近、光学显微镜自动聚焦和图像自动拼接。

关键词：扫描探针显微镜自动逼近自动聚焦图像拼接

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Aerobic granular sludge formation based on substrate availability: Effects of flow pattern and fermentation pretreatment

Quan Yuan, Hui Gong, Hao Xi, Kaijun Wang

《环境科学与工程前沿（英文）》 2020年第14卷第3期 doi: 10.1007/s11783-020-1226-0

摘要： Penetration depth and substrate characters affect AGS formation and performance. The relationship between substrate gradient and particle size affects AGS stability. The fermentation process is proposed as a pretreatment to improve AGS stability. The influences of flow patterns (mixed-flow and plug-flow) and fermentation pretreatment on aerobic granular sludge (AGS) formation with various substrate availability levels were investigated by running four identical laboratory-scale sequencing batch reactors (R1–R4), comparing two anaerobic feeding strategies and three kinds of substrates. R1 achieved faster granulation with a fast influent fill step followed by a modified anaerobic mixed-flow phase, but the AGS showed poorer stability with a cracked structure and a high suspended solids concentration in the effluent. The anaerobic plug-flow feeding mode (with influent fed slowly from the bottom) in R2 provided deeper penetration depth for the substance to reach the core of AGS and accordingly strengthen AGS stability. An acidogenic up-flow sludge bed reactor was introduced as a pretreatment to improve the AGS performance by enhancing glucose pre-fermentation (R4). AGS fed with mixed volatile fatty acids (VFA) after glucose fermentation showed similar performance compared with the reactor fed with acetate in the aspects of stability, structure, size distribution and nitrogen removal efficiency, and 74% similarity in the microbial community. For actual wastewater with low VFA concentrations, fermentation treatment was suggested as a promising pretreatment for stable AGS granulation and operation.

关键词： Anaerobic plug-flow feeding mode Anaerobic mixed-flow mode Fermentation pretreatment Substrate gradient Penetration depth

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FBRM and PVM investigations of the double feed semi-batch crystallization of 6-aminopenicillanic acid

Min SU, Lin WANG, Hua SUN, Jingkang WANG

《化学科学与工程前沿（英文）》 2009年第3卷第3期页码 282-288 doi: 10.1007/s11705-009-0018-7

摘要： 6-Aminopenicillanic acid (6-APA) is a crucial pharmaceutical intermediate in the chemistry of semi-synthetic antibiotics. The focused beam reflectance measurement (FBRM) technology and particle vision measurement (PVM) technology were employed to the processes of online-monitoring of 6-APA crystallization behavior in a double-feeding semi-batch crystallizer. Experiments were carried out with four kinds of double-feeding policies and the results were compared with the traditional single-feeding. Records and analysis of FBRM indicated that the nucleation of double feeding policy was much higher than single policy, and chord length of 6-APA was almost determined and had little change after the nucleation peak. Ostwald ripening process had no significant effect on further growth of 6-APA crystal. PVM images showed that the crystal habit of 6-APA was continuously changed during the crystallization process. The development of (002) face in the final crystal for the five feeding policies were different.

关键词： 6-aminopenicillanic acid crystallization double-feeding FBRM PVM crystal habit

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高纤维日粮对猪营养和代谢的影响综述

Atta K. Agyekum, C. Martin Nyachoti

《工程（英文）》 2017年第3卷第5期页码 716-725 doi: 10.1016/J.ENG.2017.03.010

摘要：

目前，大量的低成本、纤维类的副产物被添加到猪的日粮中以减少猪的养殖成本。然而，由于猪不能有效降解膳食纤维，因此富含纤维的日粮营养价值偏低。此外，高纤维日粮会降低营养物质的利用率和猪的生长性能。最近的研究结果不一致，甚至互相矛盾，而且纤维来源、纤维类型和纤维水平也会影响高纤维日粮的负效应。另外，测定膳食纤维及其纤维组成的分析方法会经常干扰纤维对猪生长和生理反应的影响。虽然已经有一些改善纤维对猪的消极影响、提高日粮的营养价值的方法被逐渐应用，如外源纤维降解酶广泛应用于提高营养物质利用率和猪的生长性能。但是，与研究结果并不一致，还需要阐明外源纤维降解酶在猪的代谢和生理反应中的作用方式。另外，膳食纤维日益成为促进猪的肠道健康和改善妊娠母猪福利的方法。本文对膳食纤维及其对猪的营养、肠道生理和母猪福利的影响进行了讨论。同时，本文建议要对膳食纤维和外源酶如何提高猪对高纤维原料的利用率方面进行深入的研究。

关键词：肠道生理高纤维日粮营养物质利用猪母猪福利

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Control of the agglomeration of crystals in the reactive crystallization of 5-(difluoromethoxy)-2-mercapto-1

Yongli WANG, Shuyuan MA, Xiaodong Lü, Chuang XIE

《化学科学与工程前沿（英文）》 2012年第6卷第4期页码 423-431 doi: 10.1007/s11705-012-1211-7

摘要： 5-(Difluoromethoxy)-2-mercapto-1 -benzimidazole (DMB) was precipitated by adding acetic acid to the DMB sodium salt solution. The spherical agglomeration of DMB during the reactive crystallization in a batch crystallizer was monitored by real-time Particle Video Microscope (PVM). We found that the low feeding rate of acetic acid, high crystallization temperature, low agitation rate or adding seed crystal can facilitate the formation of spherical agglomerates. By using a simple model, the mean crystal agglomerate size of DMB thus predicted is generally in agreement with the experimental data. In addition, the crystallization process of DMB was optimized by a new control strategy of supersaturation to avoid disadvantages brought by agglomeration.

关键词： 5-(difluoromethoxy)-2-mercapto-1H-benzimidazole (DMB) reactive crystallization agglomeration feeding rate crystallization temperature agitation rate