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1.
国有林场是我国生态文明建设的主力军。随着我国城市化建设步伐的不断加速,生态环境问题业日益突出,如何在保护生态环境的同时,加快经济建设的发展,成为当今林业领域的热点研究问题。本文从国有林场改革的意义、公益性国有林场的特点、国有林场改革的思路及建议、国有林场发展的方向及途径、国有林场可持续发展的措施等方面进行了探讨,以期为国有林场的发展提供借鉴。 相似文献
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基于国家治理论阐述了政府审计与国家经济安全之间的内在逻辑机理关系,认为政府审计应从以公民需求为导向,引入市场机制,健全审计问责机制三个层面出发,充分发挥政府审计“免疫系统”的防御、稳定、监视三大基本功能,并以此来构建维护国家经济安全的政府审计模型,最终实现维护国家经济安全的目标。 相似文献
3.
基于状态机的植物生长模型可视化研究 总被引:3,自引:4,他引:3
在分析植物生长形态生理变化的基础上,揭示植物生长时空状态的变化规律,提出基于状态机的植物生长模型,并引入随机矢量真实预测植物的生长。根据该模型构建植物生长的可视化算法,合理组织有关植物生长的数据,并开发一个原型系统验证了该模型的有效性。 相似文献
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为今后奶牛改良工作成果的巩固和推广提供依据,对国家奶牛良种补贴项目在泾阳实施的效果与措施进行总结.结果表明:累计使用良种冷冻精液细管23.7万支,生产改良奶牛3.15万头,且已有1.1万头的优质母牛已正式进入产奶阶段.良种补贴后代奶牛的头胎日产奶量达到27 kg左右,比同期母亲日产奶量高2 kg~3 kg;生奶平均乳... 相似文献
6.
青海省海北州是草资源较为丰富的地区,畜牧业经济在全州国民经济中占主导地位。通过调研,基本摸清了海北州草资源使用情况和存在的问题,并提出了相应的意见及建议,以期为海北州畜牧业发展再上新台阶奠定基础。 相似文献
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Suckling both, or only one contralateral mammary gland during 15 days postpartum was utilized to study lactogenic hormone binding to mammary microsomal membranes and quantitative mammary morphology in ewes. Binding of radiolabeled human growth hormone was specific for lactogenic hormones. Non-radiolabeled human growth hormone, ovine and bovine prolactin and human placental lactogen effectively competed with radiolabeled human growth hormone for binding sites but ovine and bovine growth hormone were completely ineffective. Specific binding of radiolabeled human growth hormone to 600 μg of membrane protein averaged 23 ± 3% in all lactating glands. Neither days postpartum nor treatment of contralateral mammary glands substantially altered hormone binding in lactating glands. Specific human growth hormone binding (6 ± 0.5%) in non-suckled glands (15 days postpartum both udder halves) was significantly lower (P<0.01) than in lactating tissue but only a moderate and variable reduction in specific binding was measured in membranes from glands non-suckled for 15 days but contralateral to a suckled gland (14 ± 4%). Specific binding was approximately doubled in assays with 600 compared with 300 μg of membrane protein and the pattern of binding among variously suckled glands was not changed by treatment of membranes with 4 M MgCl2 prior to assay. Most secretory cells from all lactating glands had rounded, basally displaced nuclei, apical fat globules, secretory vesicles and abundant densely stained basal cytoplasm (ergastoplasm). Alveolar lumenal area was maximal (50% of tissue area) and stromal tissue area was minimal. After 15 days of non-suckling (both udder halves) mammary cells were engorged with lipid, ergastoplasm was reduced and nuclei were irregularly shaped and randomly displaced compared with lactating tissue. In addition, lumenal area was reduced and stromal tissue more evident. Lack of suckling for 5 days had little apparent effect on mammary cytology. Like lactogenic hormone binding, mammary tissue morphology was only moderately altered by 15 days of non-suckling when the remaining gland was suckled. RNA concentration was lowest (2.1 ± 0.3 mg/g) in mammary tissue from ewes in which neither gland was suckled for 15 days postpartum but non-suckling interval had no significant effect when contralateral glands were suckled. DNA concentration was not significantly influenced by suckling treatments. Relative lactogenic hormone binding closely corresponded to changes in cytological and biochemical indices of secretory cell function. 相似文献
9.
中国国家重点保护野生植物现状 总被引:19,自引:0,他引:19
顾云春 《中南林业调查规划》2003,22(4):1-7
国家林业局于1996年始在全国范围内组织了国家重点保护野生植物资源调查,历时5年,被调查的野生植物物种共191种(含变种)。调查表明,盐桦(Betula halophila)、金平桦(Betula jinpingensis)、秤锤树(Sinojachia xylocarpa)3树种此次调查未找到。原产地野生仅存1~10株的木本植物有12种:普陀鹅耳枥(Carpinus putoensis)、绒毛皂荚(Gleditia japonica var.velutina)、丹霞梧桐(Firmiana danxiaensis)、广西火桐(Erythropsis kwangsiensis)、百山祖冷杉(Abies beshanzuensis)、羊角槭(Acer yangjuechi)、云南蓝果树(Nyssa yunnanensis)、猪血木(Euryodendron excelsum)、天目铁木(Ostrya rehderiana)、华盖木(Manglietiastrum sinicum)、滇桐(Craigia yunnanensis)、膝柄木(Bhesa sinensis)。原产地野生仅存11~100株的木本植物有9种:峨眉拟单性木兰(Parakmeria omeiensis)、天台鹅耳枥(Carpinus tientaiensis)、景东翅子树(Pterospermum kingtungense)、巧家五针松(Pinus squamata)、紫檀(Pterocarpus indicus)、梓叶槭(Acer catalpifolium)、异形玉叶金花(Mussaenda anomala)、广西青梅(Vatica guangxiensis)、毛枝五针松(Pinus wangii)。仅存50000株以下的国家重点保护的野生植物共有85种,占191种的44.5%,形势异常严峻。报告分析了不同区域和空间野生植物分布的差异、存在的问题,并提出了5点建议。 相似文献
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《The Journal of Applied Poultry Research》2015,24(2):233-239
Formal systems of inquiry are of limited value when working with rural communities in developing countries. The current research used alternative systems of inquiry and learning that involved applying participatory epidemiology (PE) techniques to collect veterinary information about Newcastle disease (ND) in rural areas. Results indicated that poultry constituted the largest proportion (42.4%) of livestock species kept, and the poultry diseases that local farmers callbingiri, ciwon-sufe,dankanoman-kaji, dangari, andgurdumu are consistent with modern veterinary knowledge of Newcastle disease, respiratory disease, coccidiosis, fowl pox, and ectoparasitism, respectively.Tsuwen zaki (lion's testicle;Cucumuis pustulatus) andgarafuni (balsam pear;Momordica balsamina) are traditional remedies used to prevent Newcastle disease. Local farmers are knowledgeable about common disease that affect their poultry; they have good diagnostic abilities and can recognize clinical signs. There should be improved veterinary outreach to share some of this information via active community participation, and PE should be incorporated into state and national disease surveillance systems. 相似文献