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41.
杨兰伟 《农业图书情报学刊》2005,17(2):103-105
本文针对农业专业图书馆转型期面临的挑战、困难 ,论述了专业图书馆必须坚持内涵发展、协调发展、稳定发展、重点发展 ,才能保证它的可持续发展 相似文献
42.
Takele Feyera Sigrid J W Skovmose Signe E Nielsen Darya Vodolazska Thomas S Bruun Peter K Theil 《Journal of animal science》2021,99(2)
This study aimed to determine the optimal supply of lactation feed during the transition period to minimize farrowing duration (FD) and maximize colostrum yield (CY) and quality with the overall aim of reducing piglet mortality. A total of 48 sows were stratified for body weight and assigned to six levels of feed supply (1.8, 2.4, 3.1, 3.7, 4.3, and 5.0 kg/d) from day 108 of gestation until 24 h after the onset of farrowing. The number of total born, live-born, and stillborn piglets; birth time and birth weight of each piglet; and frequency of farrowing assistance (FA) was recorded, and blood samples were obtained from newborn piglets at birth. Live-born piglets were further weighed at 12 and 24 h after birth to record weight gain, which in turn was used to estimate intake and yield of colostrum. Colostrum samples were collected at 0, 12, 24, and 36 h after the onset of farrowing. FD was shortest (4.2 h) at intermediate (3.7 kg/d), longest (7.1 to 7.6 h) at low (1.8 and 2.4 kg/d), and intermediate (5.6 to 5.7 h) at high (4.3 and 5.0 kg/d) feed intake (P = 0.004; mean comparison). FA was lowest (0.7% to 0.8%) at intermediate feed intake (3.7 and 4.3 kg/d) and substantially elevated (4.3% to 4.7%) at both lower and higher feed intake (P = 0.01; mean comparison). The cubic contrast revealed 4.1 kg/d as the optimal feed intake to achieve the shortest FD and to minimize FA. Newborn piglets from second-parity sows were less vital than piglets from gilts as evaluated by blood biochemical variables immediately after birth. CY was greatest at 3.1 kg/d (P = 0.04), whereas the cubic contrast revealed 3.0 kg/d as the optimal feed intake to maximize CY. Concentrations of colostral components were affected by the diet, parity, and their interaction except for lactose concentrations. In conclusion, the study demonstrated the importance of proper feed level during the transition period on sow productivity. Moreover, this study estimated 4.1 and 3.0 kg/d as the optimal feed intake during the transition period to improve farrowing characteristic and CY, respectively, and these two feed intake levels supplied daily 38.8 MJ metabolizable energy (ME) and 23.9 g standardized ileal digestible (SID) lysine (3.0 kg/d) or 53.0 MJ ME and 32.7 g SID lysine (4.1 kg/d). The discrepancy of optimal feed intake for optimal farrowing and colostrum performance suggests that it may be advantageous to lower dietary lysine concentration in the diet fed prepartum. 相似文献
43.
L. R. Raposo C. Roma‐Rodrigues P. Faísca M. Alves J. Henriques M. C. Carvalheiro M. L. Corvo P. V. Baptista A. J. Pombeiro A. R. Fernandes 《Veterinary and comparative oncology》2017,15(3):952-967
Here we describe the establishment of a new canine mammary tumour (CMT) cell line, FR37‐CMT that does not show dependence on female hormonal signaling to induce tumour xenografts in NOD‐SCID mice. FR37‐CMT cell line has a stellate or fusiform shape, displays the ability to reorganize the collagen matrix, expresses vimentin, CD44 and shows the loss of E‐cadherin which is considered a fundamental event in epithelial to mesenchymal transition (EMT). The up‐regulation of ZEB1, the detection of phosphorylated ERK1/2 and the downregulation of DICER1 and miR‐200c are also in accordance with the mesenchymal characteristics of FR37‐CMT cell line. FR37‐CMT shows a higher resistance to cisplatin (IC50>50 µM) and to doxorubicin (IC50>5.3 µM) compared with other CMT cell lines. These results support the use of FR37‐CMT as a new CMT model that may assist the understanding of the molecular mechanisms underlying EMT, CMT drug resistance, fostering the development of novel therapies targeting CMT. 相似文献
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45.
徐亮 《信阳农业高等专科学校学报》2006,16(2):115-116
青少年健康成长的外部环境包括家庭、社会和学校。必须排除外部不利因素对青少年健康成长的影响,优化家庭、社会、学校教育环境,营造有利于青少年健康成长的和谐氛围。 相似文献
46.
富宇 《农业图书情报学刊》2012,24(10):149-151
图书馆是构建社会主义和谐社会,建设和谐文化的重要组成部分。从图书馆文化责任的内涵出发,分析了图书馆在构建和谐社会中的重要性,论述了如何充分发挥图书馆的文化责任,为构建和谐社会出力献策。 相似文献
47.
学习型社会条件下成人教育师资队伍建设的思考 总被引：1，自引：0，他引：1
学习型社会的建立离不开成人教育,成人教育的发展与功能的发挥离不开具有成教特色的师资队伍。针对当前我国成教师资队伍的现存问题,广辟渠道,充实和稳定师资队伍;创新成教教师继续教育机制,增强教师的基本素质;倡导建立教师学习型组织,促进教师的自我发展;完善竞争和激励机制,激发教师工作热情是学习型社会成教师资队伍建设的必需环节和有效策略。 相似文献
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49.
张燕 《农业图书情报学刊》2007,19(7):66-68,71
主要分析了在建设社会主义“新农村”过程中,文化建设对农村整体发展的意义;讨论作为文化传播者和信息导航员的图书馆,如何培养农民的信息意识,引导农民过健康积极向上的生活,促进图书馆文化信息资源在农业发展中的利用。 相似文献
50.
狗牙根果岭的交播技术 总被引：5，自引：2，他引：5
主要介绍狗牙根果岭的交播技术 ,包括草种选择和配比、种子直播、交播前后的管理措施 ,并讨论了狗牙根果岭的春季过渡技术等。 相似文献