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61.
Background: Bearded dragons are one of the most popular pet lizard species, and biochemical reference values are useful for health management of these reptiles. Objectives: The objectives of this study were to measure plasma biochemical values in healthy captive bearded dragons, determine reference values, and evaluate the effects of sex and season on the results. Methods: Blood samples were collected from 100 captive healthy bearded dragons in Tokyo during the summer and winter. Plasma biochemical measurements were performed using a dry‐slide automated biochemical analyzer. The data were then compared based on sex and season using 2‐way ANOVA. Results: Globulin, cholesterol, and calcium concentrations of females were higher in both summer and winter compared with the values obtained for males. Both males and females had higher uric acid concentrations in winter than in summer. When compared with males, females had a higher chloride concentration in summer and a higher total protein concentration and aspartate aminotransferase activity in winter. Potassium concentration in males was lower in winter than in summer, whereas in females cholesterol concentration was lower in winter than in summer. Conclusions: Biochemical values that differed based on sex and season in bearded dragons were similar to those in other lizards. These differences reflect physiologic differences in reproductive status in females and seasonal changes in temperature and hydration status. Plasma biochemical values established for bearded dragons in this study will be useful in the diagnostic assessment of captive animals.  相似文献   
62.
对近3年<兽医临床诊断学>教学改革的效果进行了分析,具体包括教学方法改革效果、实践教学改革效果、考核方式改革效果以及其他方面的改革效果,旨在为兽医临床诊断学及其他课程教学提供有益参考.  相似文献   
63.
64.
稻草还田模式对稻田土壤速效氮、钾含量及晚稻生长的影响   总被引:11,自引:0,他引:11  
肖小平  汤海涛  纪雄辉 《作物学报》2008,34(8):1464-1469
设计了高桩翻耕抛栽、覆盖免耕抛栽和高桩免耕抛栽3种模式的田间小区试验。结果表明, 不同稻草还田模式对土壤NH4+-N含量影响较大, 对土壤速效钾含量和土壤NO3--N含量影响不大; 高桩翻耕模式的土壤NH4+-N、速效钾含量平均值比高桩免耕和覆盖免耕模式分别提高40.8%、7.5%和36.7%、2.0%; 高桩翻耕能促进水稻群体生长, 增加叶片叶绿素含量, 充分利用光能, 增强光合作用; 稻草还田以高桩翻耕模式的增产效果最好, 比高桩免耕、覆盖免耕分别增产5.8%和9.0%。以高桩翻耕稻草还田模式对土壤速效氮、钾含量及晚稻产量的影响最好。  相似文献   
65.
• Developed a two-step synthetic route to anti-plant-virus candidate NK0238. • NK0238 exhibited a broad antivirus spectrum in greenhouse. • NK0238 showed comparable antivirus activities as controls in field trials. • NK0238 was safe to birds, fish, bees and silkworms. • NK0238 has a very good prospect in commercial development. It has previously been shown that tryptophan, the biosynthesis precursor of Peganum harmala alkaloids, and its derivatives have anti-TMV activity both in vitro and in vivo. Further exploration of this led to the identification of NK0238 as a highly effective agent for the prevention and control of diseases caused by plant viruses, but the existing routes are unsuitable for its large-scale synthesis. This study optimized a route for two-step synthesis of this virucide candidate via reaction of l-tryptophan with triphosgene to produce l-tryptophan-N-carboxylic anhydride, which then reacts with n-octylamine to give NK0238 at up to 94% yield and nearly 97% HPLC purity. In addition, the route was used for the preparation of NK0238 on a>40 g scale permitting further assessment of its antivirus activity in the greenhouse and field experiments, and toxicity tests. NK0238 exhibited useful antiviral activities against a variety of viruses both in greenhouse and field experiments. The toxicity tests showed that NK0238 was not acutely toxic to birds, fish, honey bees and silkworms. The optimized route provides a solid foundation for its large-scale synthesis and subsequent efficacy and toxicity studies, its excellent activity and safety make NK0238 a promising drug candidate for further development.  相似文献   
66.
黄土高原不同粮草种植模式土壤碳氮及土壤酶活性   总被引:3,自引:0,他引:3  
通过在陇中黄土高原半干旱区对苜蓿(Medicago sativa)-作物轮作地进行长期定位试验,探讨不同种植模式对土壤碳氮形态及其相关酶活性的影响。6种种植模式分别为苜蓿-苜蓿、苜蓿-休闲、苜蓿-小麦(Triticum aestivum)、苜蓿-玉米(Zea mays)、苜蓿-马铃薯(Solanum tuberosum)和苜蓿-谷子(Setaria italica)。结果表明,苜蓿-作物种植模式不利于土壤总有机碳的积累,而苜蓿翻耕后保持休闲则可维持较高的有机碳含量;与苜蓿连作相比,苜蓿-作物种植模式的土壤有机碳降低了1.60%~23.11%,全氮含量增加了3.81%~21.83%。不同作物对土壤养分吸收利用状况不同,进而引起土壤酶发生变化。与苜蓿连作相比,苜蓿粮食作物种植模式在降低土壤过氧化氢酶和蛋白酶活性的同时,提高了土壤硝酸还原酶活性;其中土壤过氧化氢酶活性和蛋白酶活性分别降低了5.20%~12.30%和15.03%~43.43%,硝酸还原酶活性提高了1.26%~28.79%。苜蓿连作和苜蓿-粮食作物种植模式间的土壤脲酶活性无显著差异(P0.05),但均高于苜蓿-休闲处理。相关性分析结果表明,土壤脲酶活性与土壤有机碳、全氮含量呈显著正相关(P0.05),可作为衡量土壤肥力的指标。  相似文献   
67.
对柑橘大实蝇成虫羽化期、田间消长规律及活动习性的研究,结果表明:1、三个观察点成虫羽化始见日至羽化高峰的时间都在5-10天左右,羽化期为16-19天,2011年麻阳的成虫始见日和羽化高峰期比2010年提前了5-8天,2011年长沙的羽化始见日和羽化高峰期都比麻阳稍早2-4天。2、成虫从羽化至基本死亡共持续84天。成虫在田间的始见日和高峰期分别处在5月下旬和6月中下旬,2010年成虫的田间始见日和高峰期都比2011年迟5至7天。3、成虫在交配产卵前,很少飞往柑橘树上,而在橘园及周围杂草或灌木丛中觅食、栖息;当气温超过30℃,成虫飞往橘园周边高大乔木或草丛中避暑,下午16∶00以后飞往柑橘树上产卵。  相似文献   
68.

Background

It has been shown that the prevalence of both clinical attachment loss (CAL) ≥1 mm and pocket probing depth (PPD) ≥4 mm is relatively high even in younger dogs, but also that only a minority of the dogs have such clinical signs of periodontal disease (PD) in more than a few teeth. Hence, a minority of dogs carry the major PD burden. These epidemiological features suggest that screening for PD in larger groups of dogs, allowing for rapid assessment of treatment planning, or for the selection of dogs with or without PD prior to be included in experimental trials, should be possible. CAL is the central variable in assessing PD extent and severity while PPD is the central variable used in treatment planning which make these two variables obvious in a screening protocol with the dual aim of disease identification and treatment planning. The main purpose of the present study in 98 laboratory Beagle dogs was to construct a fast, simple and accurate screening tool, which is highly sensitive for the identification of dogs with PD.

Results

Examination of the maxillary P4, P3, P2, I1 and C would, in this population, result in the identification of 85.5% of all dogs and 96% of all teeth positive for CAL ≥1 mm, and 58.9% of all dogs and 82.1% of all teeth positive for PD ≥4 mm.Examination of tooth pairs, all C’s, maxillary I2, M2 and the mandibular P4 would, in this population result in identification of 92.9% of all dogs and 97.3% of all teeth positive for PD ≥4 mm, and 65.5% of all dogs and 83.2% of all teeth positive for CAL ≥1 mm. The results presented here only pertain to the present study population.

Conclusions

This screening protocol is suitable for examination of larger groups of laboratory Beagle dogs for PD and our findings indicate that diseased dogs are identified with a high degree of sensitivity. Before this screening can be used in clinical practice, it has to be validated in breeds other than Beagle dogs and in populations with larger age variation.  相似文献   
69.
动物专用头孢喹诺的研究进展   总被引:2,自引:0,他引:2  
头孢喹诺是动物专用的第4代头孢菌素类抗生素,具有广泛的抗菌和强大的杀菌作用。其抗菌活性极强,对临床分离的各种革兰氏阳性菌、革兰氏阴性菌的MIC50、MIC90值均较小;其药动学特点优良,吸收快,达峰时间短,生物利用度较高,药时曲线下面积较大,表现分布容积也很大;头孢喹诺毒性低,在动物的可食用组织中残留较少,安全性较高。国外已将该药应用于猪、牛的呼吸系统感染及牛乳房炎的治疗。为指导头孢喹诺在我国兽医临床上的合理应用,现对其抗菌活性、药动学、残留及毒性、临床应用等最新资料进行综述。  相似文献   
70.
沙罗拉纳(sarolaner)属异恶唑啉类化合物,是一种新型广谱杀虫药.沙罗拉纳已被证实通过特异性阻断昆虫γ-氨基丁酸受体和谷氨酸门控氯离子通道而显示出抗寄生虫活性.本文综述了近年来沙罗拉纳在国外伴侣动物体外寄生虫防治中的开发及临床应用情况,旨在为该药的深入研究和国内开发应用提供参考.近年来,该药主要用于犬猫等伴侣动物...  相似文献   
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