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161.
Copper is one of the essential trace elements, which plays an important part in growth and development of animals. To solve the shortcomings of high inorganic copper doses in practical production,development and effective utilization of new organic copper source has become the focus of the current industry. The author introduced the nutrition function, distribution, absorption, transshipment and excretion of copper in the body,summarized the research situation and application prospects of different copper sources in livestock production, hoping to provide the reference for popularization and application of organic copper in actual production.  相似文献   
162.
为了探索 cpxR 对鼠伤寒沙门菌的黏菌素耐药相关基因 pmrB 和 phoQ 的调控作用,用overlapping PCR扩增得到 cpxR 、 pmrB 和 cpxR 、 phoQ 共表达基因 cpxR - pmrB 、 cpxR - phoQ ,用2倍微量肉汤稀释法对构建的 pmrB 、 phoQ 单基因过表达菌株JSΔ acrB Δ cpxR :: kan /p pmrB (JSΔΔ/p B )、JSΔ acrB Δ cpxR :: kan /p phoQ (JSΔΔ/p Q )和 cpxR - pmrB 、 cpxR - phoQ 共表达菌株JSΔ acrB Δ cpxR :: kan /p cpxR - pmrB (JSΔΔ/p RB )、JSΔ acrB Δ cpxR :: kan /p cpxR - phoQ (JSΔΔ/p RQ )进行黏菌素最小抑菌浓度(MICs)的测定,同时以各菌株在LB中的OD 600 nm 值绘制生长曲线,以各菌株在不同浓度的黏菌素中的存活率绘制杀菌曲线。结果:成功构建的鼠伤寒沙门菌 pmrB 、 phoQ 的单基因过表达菌株JSΔΔ/p B 、JSΔΔ/p Q 和 cpxR - pmrB 、 cpxR - phoQ 共表达菌株JSΔΔ/p RB 、JSΔΔ/p RQ 的MIC结果显示,JSΔ acrB Δ cpxR :: kan /p cpxR (JSΔΔ/p R )的MIC值较JS下降93.75%,与本实验室前期研究结果一致。JSΔΔ/p B 、JSΔΔ/p Q 的MIC值较JS均上升3倍,而JSΔΔ/p RB 、JSΔΔ/p RQ 的MIC值较JS分别降低50%和75%。生长曲线结果显示JSΔΔ/p R 的生长活性最低,JSΔΔ/p B 、JSΔΔ/p Q 、JSΔΔ/p RB 和JSΔΔ/p RQ 的生长活性均低于JSΔ acrB Δ cpxR :: kan /pHisA(JSΔΔ/pHisA)。黏菌素的杀菌曲线结果显示JSΔΔ/p B 和JSΔΔ/p Q 在不同浓度的黏菌素中的存活率显著高于黏菌素较敏感的JSΔΔ/p RB 和JSΔΔ/p RQ 。上述结果表明:CpxR能够通过PmrB和PhoQ调控鼠伤寒沙门菌对黏菌素的敏感性。  相似文献   
163.
The purpose of this report was to discuss the diagnosis, treatment, and outcome of a cat with an orbital lacrimal gland adenocarcinoma. A 14.5‐year‐old spayed female domestic shorthair cat was evaluated for a firm swelling at the left dorsotemporal orbital rim. The orbital mass was excised with preservation of the globe, and adjunctive cryotherapy was performed. A definitive diagnosis of lacrimal gland adenocarcinoma was obtained after histopathologic evaluation and histochemical staining with periodic acid–Schiff and mucicarmine. Thirteen months postoperatively, tumor regrowth occurred with a much larger osteolytic lesion, and a second surgery was performed consisting of tumor excision with implantation of carboplatin‐impregnated calcium sulfate hemihydrate beads. The cat has remained free of recurrence 11 months after the second surgery (26 months after initial diagnosis and surgery). A feline orbital lacrimal gland adenocarcinoma was successfully managed utilizing globe‐preserving surgical excision with adjunctive cryotherapy and subsequent carboplatin‐impregnated bead implantation. Orbital lacrimal gland adenocarcinoma in cats may not be as aggressive as other forms of periocular, head, and neck adenocarcinomas.  相似文献   
164.
【目的】通过现场试验、测试,对二塘沟水库右坝肩主要工程地质问题进行准确评价分析,为设计提供合理的地质参数和建议。【方法】以二塘沟水库右岸坝肩区为主要研究对象,进行现场岩石鉴定试验,钻孔压水试验,平洞岩石构造观测试验,室内岩石化学成分分析试验等。【结果】二塘沟水库右岸地形较为陡峭,岩性主要为层状凝灰岩夹凝灰质砂岩和砂岩。水库右坝肩整体构造发育:岩体完整性较差,靠近断层附近透水性和深度较大。据钻孔和平洞揭露,岩体强风化层厚2~3m,岩体较破碎。据钻孔水质分析得知,右岸地下水硫酸根离子含量514.37mg/L,具有结晶类硫酸盐型腐蚀性。【结论】二塘沟水库右坝肩岩体存在较深和较长的中等透水带、裂隙密集带和断层破碎带岩石碎屑水溶盐含量较高,岩体和地下水中硫酸盐对混凝土存在腐蚀性问题。  相似文献   
165.
实验以香椿(Toona sinensis)种子为材料,研究硫酸卡那霉素处理对其生理特性的影响,研究的主要因素包括:过氧化物酶的活性、丙二醛的含量和电导率。结果表明:适当浓度的硫酸卡那霉素处理对香椿种子活力有很大的提升,低浓度或过高浓度影响不大。  相似文献   
166.
Sulfur (S) availability in soils of agriculturally cultivated locations in the intermediate midhill zone of the Jammu region of India is a major concern. The total S content ranged between 193 and 774 mg kg?1. The organic S and nonsulfate S were relatively higher and contributed on average 49.05 and 46.71% of total S, respectively. Inorganic sulfate S contributed least to the total S (0.93 to 11.98%), water‐soluble S from 2.21 to 14.82%, and adsorbed S from 7.15 to 50.26%. All the forms of S except adsorbed S correlated positively and significantly with organic carbon content of soils. The multiple regression analysis revealed that the organic carbon content had greater impact on different S forms followed by clay content. Among different forms of S, total S was correlated positively and significantly with organic S (r = 0.983??) and nonsulfate S (r = 0.980??).  相似文献   
167.
《Plant Production Science》2013,16(4):332-338
Abstract

The spikelet number (SPN) is an important wheat yield component decided before anthesis. Our objective was to determinethe effect of nitrogen (N) from urea and ammonium sulfate split-applied at different rates before anthesis on the SPN in the recent Egyptian cultivars Sakha93 and Sakha94 and two commonly used cultivars in pots. The response of SPN to applied Nfrom ammonium sulfate was higher than that from urea in all four cultivars used. However, there was no difference in the responses of SPN to absorbed N from the two fertilizers in any of the cultivars. The SPN per applied and absorbed N was thehighest in Sakha94 among the four cultivars. These cultivar differences in the SPN were due to the difference in the spikenumber. The results suggested that the N from ammonium sulfate has a greater effect on SPN than that from urea in recent Egyptian cultivars.  相似文献   
168.
以氨基葡萄糖盐酸盐为原料,通过甲醇钠方法制备氨基葡萄糖硫酸钠盐。氨基葡萄糖盐酸盐先与甲醇钠反应生成氨基葡萄糖碱,再与三氧化硫反应,得白色粉末状产品。经物理和化学分析,其[α]  相似文献   
169.
The growing problem of antimicrobial resistance affects veterinarians on a daily basis. Antimicrobial stewardship and responsible prescribing are essential for a future with effective antimicrobials, as it is unlikely that new antimicrobials will become available for use in horses in the near future. Extended-spectrum β-lactamase (ESBL) producing Enterobacteriaceae, methicillin-resistant Staphylococcus aureus (MRSA) and Salmonella spp. are pathogens of significant concern but there are also other opportunistic pathogens such as Pseudomonas spp., α-haemolytic Streptococcus spp., Enterococcus spp. and Acinetobacter spp. which, due to their high intrinsic resistance, have limited treatment options in adult horses. It is essential that highest priority critically important antimicrobials such as ceftiofur, enrofloxacin, rifampicin and polymyxin B are used prudently in horses and ideally based on culture and antimicrobial susceptibility testing (AST). For example, the use of polymyxin B at a low anti-endotoxic dose rather than at a higher antimicrobial dose in horses for the treatment of systemic inflammatory response syndrome is a potential driver for resistance to colistin (polymyxin E), an antimicrobial used as a last resort in the treatment of multidrug resistant (MDR) Enterobacteriaceae infections in humans. Serum procalcitonin levels are used in humans to distinguish noninfectious inflammatory conditions from inflammation caused by bacteria and other infectious agents and are also used to guide cessation of antimicrobial treatment. Although no such studies have been performed in horses, this or other markers may prove to be helpful in guiding antimicrobial treatment decisions in the future. Optimising sampling techniques and good communication with the microbiology laboratory are essential for generating the accurate culture and AST results that underpin appropriate antimicrobial use. Additionally, there is clearly a need for national and international harmonisation of laboratory methods in order to improve the reliability and consistency of results reported by different laboratories.  相似文献   
170.
硫酸铈作为松香酯化催化剂的研究   总被引:13,自引:4,他引:13  
研究了硫酸铈(Ce(SO4)2·4H2O)对松香酯化反应的催化作用,系统探讨各反应因素对酯化反应的影响。研究发现它具有较高的催化活性,而且反应后处理程序简单。  相似文献   
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