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181.
锌素营养对作物叶片解剖结构的影响   总被引:12,自引:0,他引:12  
采用水培方法,调节锌素营养供应,观察芹菜、玉米、小麦幼苗生长及幼苗叶片解剖结构。结果看出,锌素营养不足时植株含匀量降低,生长受到抑制:叶肉细胞收缩,细胞间隙增大,叶肉细胞中叶绿体数量减少。禾本科作物维管柬鞘细胞中叶绿体减少尤为明显,但对叶绿体的体积无影响;辅导组织发育受到抑制,机械组织不发达。锌素营养过剩时细胞结构破坏,叶肉细胞严重收缩,叶绿体明显减少。  相似文献   
182.
以大五星枇杷为对照,调查了引种四川的5个日本枇杷品种的植物学性状,测定果实维生素C、总酸、总糖及可溶性固形物等含量。结果表明,引进品种里见和有间综合性状表现最好,除可食率低于大五星外,单株产量与大五星无显著差异,单果重、维生素C、可溶性固形物含量等都高于大五星,适合在四川地区种植。  相似文献   
183.
Infectious bovine keratoconjunctivitis (IBK) is an acute disease caused by Moraxella bovis (Mb). Several factors may predispose animals to an IBK outbreak; one commonly observed is infection with bovine herpes virus type 1 (BHV-1). The aim of this study was to investigate the dynamics of BHV-1 virus infection and its relation with clinical cases of IBK in weaned calves from a beef herd with a high prevalence of lesions caused by Mb. Sampling was carried out in six stages and included conjunctival swabs for isolating Mb as well as blood samples for identifying antibodies specific for BHV-1. A score for IBK lesions after observing each eye was determined. The findings of this study showed a high prevalence of BHV-1 virus infection (100% of animals were infected at the end of the trial); 67% of animals were culture-positive for Mb, but low rates of clinical IBK (19% of calves affected) were detected at the end of the trial. These results suggest that infection with BHV-1 did not predispose these animals to IBK, and that Mb infection produced clinical and subclinical disease in the absence of BHV-1 co-infection.  相似文献   
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Repair of hernias of the abdominal wall of horses is often augmented by inserting a prosthetic mesh. In this review, we describe the various characteristics of prosthetic meshes used for hernia repair and present 2 systems that are used by surgeons in the human medical field to classify techniques of prosthetic mesh herniorrhaphy. Both of these classification systems distinguish between onlay, inlay, sublay, and underlay placements of mesh, based on the location within the abdominal wall in which the prosthetic mesh is inserted. We separate the published techniques of prosthetic mesh herniorrhaphy of horses using this classification system, ascribing names to the techniques of herniorrhaphy where none existed, and report the success rates and complications associated with each technique. By introducing a classification system widely used in the human medical field and illustrating each technique in a figure, we hope to clarify inconsistent nomenclature associated with prosthetic mesh herniorrhaphy performed by veterinary surgeons.  相似文献   
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拉旦 《青海草业》2019,(1):30-31,16
为积极探索构建粮饲兼顾、农牧结合、循环发展的新型草牧业结构和模式,在青海半农半牧地区推广青稞秸秆利用,减少秸秆浪费和营养流失,切实提高青稞秸秆价值,促进农牧民稳步持续增收,掌握青稞秸秆加工利用技术意义重大。  相似文献   
189.
草业是青海经济开发与生态环境治理的基础   总被引:8,自引:0,他引:8  
拉元林 《草业科学》2002,19(4):7-10
分析了青海经济开发与生态环境失调产生的问题及生态环境失调的主要原因,指出在经济发展中忽视生态环境治理和在生态环境治理上实行重林轻草违背自然规律的失误,草业是青海经济开发与生态环境治理的基础。  相似文献   
190.
The addition of 0.5% (v/v) of Equex STM Paste (Nova Chemical Sales, Scituate Inc., MA, USA), whose active ingredient is sodium dodecyl sulphate (SDS), to a Tris–egg yolk extender was demonstrated to improve the longevity of frozen–thawed dog spermatozoa during in vitro incubation at 38°C. The aim of the first experiment was to compare the effects of two SDS‐containing compounds, Equex STM Paste and Equex Pasta (Minitüb, Tiefenbach, Germany), when added to a Tris–egg yolk based extender, on the post‐thaw longevity of dog spermatozoa, as well as on the intracellular Ca2+ concentration of spermatozoa, during post‐thaw incubation at 38°C. The post‐thaw sperm survival and longevity, as well as the quality of the sperm movement, were significantly better when using Equex STM Paste. Such prolonged sperm longevity, however, was associated to a higher intracellular Ca2+ concentration in a large subpopulation of the live spermatozoa. A second experiment was aimed to evaluate the effects of sperm dilution immediately post‐thaw with a Tris buffer containing glucose or fructose. The two Tris buffers were no different for any of the sperm parameters studied. The aim of a third experiment was to evaluate the sperm longevity, motility patterns and intracellular Ca2+ concentration of cryopreserved dog spermatozoa during post‐thaw incubation in capacitating conditions [canine capacitating medium (CCM) with or without 5 μg/ml of heparin]. Heparin had no significant effects on any of the sperm parameters evaluated. During the first 8 h of incubation, the majority of the live spermatozoa had a high intracellular Ca2+ content. However, after 8–10 h of incubation, it had significantly declined. The highest proportion of fast motile sperm, and the highest curvilinear velocity, average path velocity and amplitude of lateral head displacement for the total motile sperm were observed during the 2–4‐h incubation period. It was concluded that: (a) the addition of 0.5% (v/v) of Equex STM Paste to a Tris–egg yolk based extender significantly improved the post‐thaw longevity of dog spermatozoa, but the same concentration of Equex Pasta had no significant beneficial effects; (b) sperm dilution after thawing with a Tris buffer containing glucose or fructose made no difference in post‐thaw sperm longevity; (c) the addition of 5 μg/ml of heparin to CCM had no significant capacitating effects on frozen–thawed dog spermatozoa.  相似文献   
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