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81.
82.
农村小规模养猪存在的问题与对策 总被引:1,自引:1,他引:0
农村小规模养猪,仍是养猪业的主体。文章以广西荔浦县为例,分析农村小规模养猪存在水平低、防疫意识弱、管理不善等诸多问题,并针对问题,提出系列对策:必须具备养殖技术知识;建设符合要求猪舍,搞好清洁卫生并定期消毒;加强品种意识;坚持以防为主,治疗为辅的原则;科学饲养,科学管理。 相似文献
83.
可持续发展是烟草行业现代化的发展方向,也是增强烟草行业核心竞争力的重要主题。笔者分析了2017—2020年云南省烟叶可持续发展规范(STP)的实施情况及对云南烟叶出口量的影响,总结了领导机制的建设、专项资金的灵活使用、人才队伍的建设、数字化管理平台的构建方面的主要做法。认为云南STP的实施间接地影响了全省烟叶安全性、生产方式及生产管理理念,云南烟叶出口适销率逐年上升。结合云南烟叶生产实际,为保障STP生产管理的有效实施,提出建立STP行业标准、强化劳动用工规范、推进质量追溯、以绿色销售拉动绿色生产。 相似文献
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我国是世界水果生产大国,随着近年来果园生草覆盖技术的推广,果园割草机快速发展迫在眉睫。分析和阐述了我国果园割草机切割装置、行走系统、仿形装置等关键部件,以及导航、避障和自动识别等关键技术的相关发展,同时介绍和分析了国内外割草机的发展现状,结合牵引式、自走式等割草机类别,归纳了部分国内外具有代表性的割草机机型、特点及存在的问题。结合矮砧密植与乔砧适植两种果园种植模式,总结了我国割草机发展过程中农机农艺结合较差、研发制造水平较低、机具作业速度与割刀工作速度匹配不当、高新技术应用欠缺等问题,提出了在割草机应用中应注重与农艺相结合,提升设计研发与生产制造水平,注重解决割草机作业速度与割刀工作速度的匹配,加强高新技术应用,尽早实现割草机自动化、智能化、信息化应用,推进果园机械化除草进程。 相似文献
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AIM:To explore the relationship between change of serum melatonin (MT) and pathogenesis of hepatic encephalopathy (HE). METHODS: Changes of MT level in sera of cirrhosic patients with HE and without HE were determined by ELISA, normal serum served as control. The change of serum MT level in exacerbation and remission in HE was also determined.RESULTS:MT level in patients with HE was higher than that withour HE (P<0.01). MT levels of both groups were higher than that of normal group (P<0.01). They were (308.53±59.07) ng/L, (139.85±34.59)ng/L,(77.73±28.41)ng/L, respectively. Serum MT level in exacerbation was higher than that in remission (P<0.01), they were (301.52±66.42)ng/L and (147.81±23.31) ng/L, respectively. CONCLUSION: The elevation of MT content in sera may be closely related to the onset of hepatic coma. 相似文献
88.
AIM:To investigate the relationship between trace elements and oxidative stress in diabetic diaphragm. METHODS: Contents of copper(Cu), manganese(Mn), zinc(Zn), iron(Fe),cadmium(Cd),chromium(Cr),cobalt(Co),molybdenum(Mo) and lithium(Li) in the alloxan-induced diabetic rat diaphragm muscles were measured by atomic absorption spectrophotometer, andtheir superoxide dismutase(SOD) activities and malondiadehyde(MDA) contents were detected. RESULTS: The contents of Cu, Zn, Cr and Li were lower and the Fe and Cd were higher in diabetic rat diaphragm muscles than that of the control group, but there were no significant differences in Mn, Co and Mo, between control and diabetic group. SOD activities decreased significantly and MDA contents increased significantly in diaphragm of diabetic rats as compared with the control group.In addition,in diabetic rats diaphragm, there was a positive correlation between Zn and SOD, and negative correlation between Zn and MDA, and Cd and SOD. CONCLUSION: Changes of the contents of Cu, Zn, Fe, Cd, Cr, Li and the increase of oxidative stress in diaphragm were found in the early diabetes, and Zn, Cd play an importment role in oxidative stress of diabetic diaphragm. 相似文献
89.
Neurovascular unit (NVU) is composed of neurons, endothelial cells, pericytes, astrocytes, macrophages/microglia, smooth muscle cells, extracellular matrix, etc, and plays vital roles in maintenance of the normal brain tissue function and cellular homeostasis. Cerebral ischemia caused by stroke can harm various components of NVU. Repairing damaged NVU and maintaining its structural and functional integrity are an effective way to improve stroke treatment. Resent research has found that rapamycin not only enhances autophagy of neurons but also effectively repairs the injuried components of NVU , thereby reducing neural damage after stroke. In this paper, the mechanisms of rapamycin underlying the repair of injured NVU after ischemic stroke is reviewed to provide guidance for its application in the treatment of stroke. 相似文献
90.
AIM To evaluate the effect of swimming on experimental endometriosis in rats. METHODS 80 female SD rats were divided into 8 groups, including control group, model group and animals performed light exercise (swimming once a week), moderate exercise (swimming 3 times a week), and intense exercise (swimming 5 times a week) before or after endometriosis induction,10 rats in each group. The mRNA and protein expressions of fatty acid synthase (FAS), matrix metalloproteinase 9 (MMP9) and proliferating cell nuclear antigen (PCNA) in endometrium of rats were detected. RESULTS The swimming before the induction of the edometriosis lesions did not prove to have aprophylactic role against endometriosis, whereas the swimming after induction of the lesions had a beneficial effect regardless of frequency, with a greater reduction in the groups practicing moderate and intense activity (P< 0. 05), an increase in FAS levels and a decrease in MMP9 and PCNA levels were also observed (P< 0. 05). CONCLUSION Swimming after induction of the edometriosis is beneficial for the treatment of endometriosis, the mechanism may be related to the expression of FAS, MMP9 and PCNA protein. 相似文献