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排序方式: 共有456条查询结果,搜索用时 15 毫秒
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Stan Veytsman DVM Pierre Amsellem DVM MS DACVS-SA Brian D. Husbands DVM DACVIM Aaron K. Rendahl BA BS PhD Philip J. Bergman DVM MS PhD DACVIM Guillaume Chanoit DEDV MSc PhD DECVS/DACVS-SA Colleen Hickey DVM Kristy R. Cash DVM Karl C. Maritato DVM DACVS-SA Francesco Collivignarelli MS PhD Jolle Kirpensteijn DVM PhD DECVS/DACVS-SA 《Veterinary surgery : VS》2023,52(1):42-50
444.
为了对卷烟烟气安全性评价及烟叶生产合理选择农药品种提供数据支撑,向3R4F 标准卷烟中添加126种农药混合标准溶液,采用色谱、色谱-串联质谱联用法测定卷烟燃吸后每种农药在主流烟气、侧流烟气、烟灰和烟蒂中的迁移量。结果表明:1)126种农药在烟灰中均无迁移,在主流烟气、侧流烟气和烟蒂中的平均迁移率为侧流烟气(10.81%)>主流烟气(7.11%)>烟蒂(5.04%),平均总迁移率为22.96%。2)126种农药在主流烟气、侧流烟气、烟蒂中的平均迁移率以异狄氏剂最高,分别为31.67%、48.94%和17.32%;以溴氰菊酯最低,分别为0.04%、0.09%和0.03%。3)8类农药在主流烟气、侧流烟气、烟蒂中的平均迁移率,抑芽剂类分别为13.16%、21.74%和10.27%,有机氯杀虫剂、除草剂及拟除虫菊酯类杀虫剂分别为8.67%~10.11%、15.72%~17.28%和5.65%~6.74%,有机磷杀虫剂和杀菌剂、杂环类杀虫剂、氨基甲酸酯类杀虫剂分别为1.70%~5.26%、1.90%~6.11%和1.22%~4.55%。结论:不同农药在卷烟燃吸过程中的迁移行为差异较大。 相似文献
445.
【目的】比较浸泡和粉碎2种不同加工方式的玉米粒对绵羊的自由采食和消化的影响。为提高绵羊对玉米颗粒的消化和饲养提供参考依据。【方法】选取6只3岁、体重为(55.0±3.8)kg的健康小尾寒羊公羊,随机分为3组,每组2只。按照3×3拉丁方设计,在3个试验期给各组绵羊分别饲喂组成相同(70%混合精料+30%粉碎玉米秸秆,其中玉米含量55%)、但玉米处理不同的日粮(1、2和3),即整粒玉米为对照组(日粮1)、粉碎玉米(日粮2)、浸泡60~72 h的整粒玉米(日粮3)。【结果】3种日粮的干物质自由采食量分别为(1 566.9±121.6)、(1 579.6±98.5)和(1 466.1±101.2)g/羊/d,日粮3比日粮1和2分别显著降低6.4%(P<0.05)和7.2%(P<0.05)。干物质表观消化率分别为(57.92±0.63)、(62.63±0.53)和(66.39±0.75)%,日粮3比日粮1和2分别显著增加14.6%(P<0.05)和6.0%(P<0.05)。干物质消化量分别为(907.5±59.4)、(989.3±92.5)和(953.4±78.5)g/羊/d,日粮3比日粮1和2分别显著增加5.0%(P<0.05)和减少3.6%(P<0.05)。但日粮3和日粮2比日粮1粗纤维消化率和消化量均无显著差异(P > 0.05)。【结论】日粮中使用浸泡玉米饲喂绵羊会降低绵羊的自由采食量,但同时会提高绵羊的表观消化率,表明浸泡玉米饲喂更有利于促进绵羊的消化。 相似文献
446.
土壤含水量(soil water content, SWC)和土壤含盐量(soil salt content, SSC)是影响作物生长和农业生产力的重要因素。光学卫星图像已成为SWC和SSC估计的主要数据源。然而,在SWC或SSC变化较大地区,土壤水分和盐分会影响对方对光谱反射率的响应,使得SSC和SWC的反演精度较差。对此,该研究提出了一个半解析性的反射率模型—RVS模型,来模拟植被光谱反射率(Rv)对作物根区土壤含水量和含盐量的响应;并通过构建的RVS模型,对植被覆盖区域的土壤含水量和土壤含盐量进行同步监测。研究表明:RVS模型在反演研究区土壤含盐量和含水量时,精度较为可靠(水分:决定系数R2为0.63~0.74,均方根误差为0.017~0.028;盐分:决定系数R2为0.68~0.75,均方根误差为0.0525~0.0617)。在作物生长过程中,植被光谱反射率对深层土壤的含水量和含盐量的响应比对浅层土壤的含水量和含盐量的响应更加明显,而且随着作物的生长,影响光谱反射率的主导因素从土壤水分慢慢转向土壤盐分和水盐相互作用。该研究在一定程度上揭示了土壤水分、盐分、水盐交互作用对作物光谱反射率的干扰过程,实现土壤水分和盐分的同步监测,对实现区域尺度上土壤含盐量和含水量的精准监测具有一定的意义。 相似文献
447.
Late onset cerebellar cortical degeneration in a koala 总被引:1,自引:1,他引:0
M Kuwamura F Murai S Nishioka M Aoki F Ohashi J Yamate T Kotani BA Summers 《Australian veterinary journal》2009,87(8):342-344
A 10-year-old male koala started to fall from the tree while sleeping. Subsequently, the koala often fell down while walking and showed a gait abnormality, abnormal nystagmus and hypersalivation. At 12 years of age, the koala became ataxic and seemed blind. At 13 years of age, the koala exhibited signs of dysstasia and was euthanased. Necropsy revealed marked symmetrical atrophy of the cerebellum. Histopathologically, a severe loss of Purkinje and granule cells was evident in the cerebellum, while the molecular layer was more cellular than normal with cells resembling small neurons, which were positively stained with parvalbumin immunohistochemistry. Reactive Bergmann glial cells (astrocytes) were present adjacent to the depleted Purkinje cell zone. The very late onset and slow progression of the cerebellar cortical degeneration in this case is particularly interesting and appears to be the first report in the koala. 相似文献
448.
MANDI J. LOPEZ DVM MS PhD Diplomate ACVS KECHIA M. DAVIS DVM Diplomate ACVS SUSAN L. JEFFREY‐BORGER BA MS DVM MARK D. MARKEL DVM PhD Diplomate ACVS CHRISTY RETTENMUND DVM 《Veterinary surgery : VS》2009,38(8):920-926
Objectives— To determine interobserver repeatability of measurements on computed tomography (CT) images of lax canine hip joints at different ages and in the presence of degenerative joint disease at maturity. Study Design— Longitudinal observational investigation. Animals— Sibling crossbreed hounds. Methods— Pelvic CT was performed at 20, 24, 32, 48, 68, and 104 weeks of age. Measures were performed on 3 contiguous two‐dimensional (2D) transverse CT images of both hips at each time point by 3 investigators. Center‐edge angle (CEA), horizontal toit externe angle (HTEA), ventral (VASA), dorsal (DASA), and horizontal (HASA) acetabular sector angles, acetabular index (AI), and percent femoral head coverage (CPC) were measured. Interobserver repeatability was quantified with the intraclass correlation coefficient (ICC). Satisfactory repeatability was considered when ICC≥0.75. Results— DASA, CEA, and CPC were repeatable in all age groups. HASA and HTEA were repeatable for all but 1 time point. At 20 weeks of age, all measures but AI were repeatable, and at 104 weeks of age, DASA, CEA, CPC, and HASA were repeatable. Measures were repeatable in hips with and without degenerative changes with the exceptions of AI and HASA in normal hips and VASA and HTEA in osteoarthritic hips. Conclusions— Most 2D CT measurements examined were repeatable regardless of age or joint disease. Clinical Relevance— Two‐dimensional CT measures may augment current techniques for assessing joint changes in lax canine hips. 相似文献
449.
The objective of this study was to compare the efficiency of oestrus induction protocols on Kilis dairy goats kept on a goat farm situated close to Kilis, Turkey. Eighty goats were assigned randomly into four groups of 20 animals each in a factorial arrangement: (i) untreated control (CON), (ii) melatonin implant (MEL), (iii) CIDR-G (CIDR) and (iv) melatonin implant plus CIDR-G (MC). Experiments were performed in mid-anoestrus season under natural photoperiod environment. The differences among treatment groups in oestrus response were significant. Oestrus response was higher in the MC group than in other groups (p < 0.05). A significant difference was observed in the time interval from cessation of treatment to the onset of oestrus among treatments. The CIDR-G treatment reduced intervals from buck introduction to oestrus. The time to onset of oestrus in both the MC and CIDR groups was significantly shorter, compared with the MEL and CON groups (p < 0.05). The number of does kidding and fertility were not different among treatment groups (p > 0.05). Fecundity was similar among goats in all groups. Prolificacy and twining rates showed similar trends as fecundity rates, with no differences (p > 0.05) between treatments. The results of this study showed that oestrus in Kilis does can be effectively induced by using melatonin and CIDR combined treatment, and fertility will not be adversely affected. However, this treatment did not improve fecundity, prolificacy and twining rates. 相似文献
450.
Lori M MacDougall DVM James A Hethey BSc Alex Livingston† BSc BVetMed PhD Diplomate ECVPT FRCVS Christopher Clark‡ BA VetMB MVetSc Diplomate ACVIM Cindy L Shmon DVM MVSc Diplomate ACVS & Tanya Duke-Novakovski BVetMed DVA Diplomate ACVA Diplomate ECVAA 《Veterinary anaesthesia and analgesia》2009,36(5):512-522