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1.
根据云南省推广甘蔗收获机械的实际情况,从农户层面探究推广中存在的主要问题,分析宣传推广效果不佳的具体原因,从多个角度提出增强推广应用效果的可行性建议,为促进甘蔗收获机械在云南地区的应用提供参考。 相似文献
2.
以不同血缘及不同世代的遗传育种材料为母本、高频孤雌生殖诱导系辽诱1和CAU5等为父本杂交诱导产生的单倍体子粒为实验材料,研究秋水仙素浓度为0.625 mg/mL的条件下,用喷淋加倍设备对试验材料进行8 h喷淋的加倍效果。结果表明,喷淋秋水仙素后,郑单958的S2代的材料加倍率最高,为33.75%;第2位的是L3258×H71,是NSS种质S0代材料,其加倍率为13.02%;第3位的是D299/PH4CV,为NSS种质S1代材料,加倍率为10.34%。研究表明,喷淋秋水仙素的加倍效果与遗传背景关系紧密,喷淋秋水仙素加倍率总体由高到低的顺序为郑单958NSS种质(SS+NSS)种质SS种质欧洲杂交种,喷淋秋水仙素对全部试验材料的加倍率都有提高作用,比自然加倍提高0.83~5.08倍。利用该喷淋设备加倍单倍体子粒,具有节约用药量、操作简便、便于大规模生产应用、减少人员对秋水仙素的接触、废液回收方便、有利于保护环境等优点。 相似文献
3.
Recent breakthroughs in CRISPR technology allow specific genome manipulation of almost all crops and have initiated a revolution in precision crop breeding. Rationally-based regulation and widespread public acceptance are needed to propel genome-edited crops from laboratory to market and to translate this innovative technology into agricultural productivity. 相似文献
4.
农畜产业作为内蒙古地区的优势产业,对区内经济发展起着关键的作用。为此,本文分析内
蒙古积极发展农畜产品生产加工基地的优势,结合发展的现状,提出积极发展农畜产品生产加工输出
基地的对策,为产业稳定发展提供理论参考和借鉴。 相似文献
5.
农业生产基地项目具有影响范围大、产品服务多元化等特点,涉及行业类别较多,其环境影响评价文件也相对复杂。环境影响评价报告编制单位应充分与建设方进行沟通,熟悉项目建设内容,挖掘项目可能的产生污染的环节和设施,明确环境影响范围和环境敏感点,并对项目损益进行两方面的分析。 相似文献
6.
7.
牧草种子基地建设基本经验和措施初探 总被引:5,自引:4,他引:1
牧草种子基地建设是我国重大生态建设的基础性建设项目。该项目的建立,对满足生态建设和退耕还草、退牧还草的种子需要具有重要意义。通过4年多的建设和实践证明:牧草种子基地建设一定要建立在有可靠、准确、翔实的基础资料和科学、合理的设计之上。按照建设方案和遵守规章制度是项目建设的基本要求,科学的管理和经营是基地长期存在的必要条件。要根据目前种子市场,正确处理和调整好牧草种子与牧草及草产品之间的关系,采用先进的管理措施,多方位、多思路求发展,才能提高牧草种子基地的经济效益,逐步促使牧草种子基地规范化、标准化。 相似文献
8.
Assessing the influence of mechanical ventilation on blood gases and blood pressure in rattlesnakes 下载免费PDF全文
Mads F Bertelsen Rasmus Buchanan Heidi M Jensen Cleo AC Leite Augusto S Abe Søren S Nielsen Tobias Wang 《Veterinary anaesthesia and analgesia》2015,42(4):386-393
ObjectiveTo characterize the impact of mechanical positive pressure ventilation on heart rate (HR), arterial blood pressure, blood gases, lactate, glucose, sodium, potassium and calcium concentrations in rattlesnakes during anesthesia and the subsequent recovery period.Study designProspective, randomized trial.AnimalsTwenty one fasted adult South American rattlesnakes (Crotalus durissus terrificus).MethodsSnakes were anesthetized with propofol (15 mg kg−1) intravenously, endotracheally intubated and assigned to one of four ventilation regimens: Spontaneous ventilation, or mechanical ventilation at a tidal volume of 30 mL kg−1 at 1 breath every 90 seconds, 5 breaths minute−1, or 15 breaths minute−1. Arterial blood was collected from indwelling catheters at 30, 40, and 60 minutes and 2, 6, and 24 hours following induction of anesthesia and analyzed for pH, PaO2, PaCO2, and selected variables. Mean arterial blood pressure (MAP) and HR were recorded at 30, 40, 60 minutes and 24 hours.ResultsSpontaneous ventilation and 1 breath every 90 seconds resulted in a mild hypercapnia (PaCO2 22.4 ± 4.3 mmHg [3.0 ± 0.6 kPa] and 24.5 ± 1.6 mmHg [3.3 ± 0.2 kPa], respectively), 5 breaths minute−1 resulted in normocapnia (14.2 ± 2.7 mmHg [1.9 ± 0.4 kPa]), while 15 breaths minute−1 caused marked hypocapnia (8.2 ± 2.5 mmHg [1.1 ± 0.3 kPa]). Following recovery, blood gases of the four groups were similar from 2 hours. Anesthesia, independent of ventilation was associated with significantly elevated glucose, lactate and potassium concentrations compared to values at 24 hours (p < 0.0001). MAP increased significantly with increasing ventilation frequency (p < 0.001). HR did not vary among regimens.Conclusions and clinical relevanceMechanical ventilation had a profound impact on blood gases and blood pressure. The results support the use of mechanical ventilation with a frequency of 1–2 breaths minute−1 at a tidal volume of 30 mL kg−1 during anesthesia in fasted snakes. 相似文献
9.
N.J. Cave S.T. Koo 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2015,29(3):781-785
Background
Electrochemical approach to the assessment of acid‐base states should provide a better mechanistic explanation of the metabolic component than methods that consider only pH and carbon dioxide.Hypothesis/Objectives
Simplified strong ion equation (SSIE), using published dog‐specific values, would predict the measured serum pH of diseased dogs.Animals
Ten dogs, hospitalized for various reasons.Methods
Prospective study of a convenience sample of a consecutive series of dogs admitted to the Massey University Veterinary Teaching Hospital (MUVTH), from which serum biochemistry and blood gas analyses were performed at the same time. Serum pH was calculated using the SSIE, and published values for the concentration and dissociation constant for the nonvolatile weak acids (Atot and K a), and subsequently was compared with the dog''s actual pH . To determine the source of discordance between and , the calculations were repeated using a series of substituted values for Atot and K a.Results
The did not approximate the for any dog (P = 0.499, r 2 = 0.068), and was consistently more basic. Substituted values Atot and K a did not significantly improve the accuracy (r 2 = 0.169 to <0.001). Substituting the effective SID produced a strong association between and (r 2 = 0.977).Conclusions and clinical importance
Using the simplified strong ion equation and the published values for Atot and K a does not appear to provide a quantitative explanation for the acid‐base status of dogs. Efficacy of substituting the effective SID in the simplified strong ion equation suggests the error lies in calculating the SID. 相似文献10.