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31.
Magnetoelectronics 总被引:4,自引:0,他引:4
GA Prinz 《Science (New York, N.Y.)》1998,282(5394):1660-1663
An approach to electronics is emerging that is based on the up or down spin of the carriers rather than on electrons or holes as in traditional semiconductor electronics. The physical basis for the observed effects is presented, and the initial successful applications of this technology for information storage are reviewed. Additional opportunities for the exploitation of this technology, which are currently under study, are described. 相似文献
32.
Schenker R Bowman D Epe C Cody R Seewald W Strehlau G Junquera P 《Veterinary parasitology》2007,145(1-2):90-93
Two studies were performed to examine the efficacy of milbemycin oxime against fourth-stage larvae or adults of Toxocara cati. In the study to determine efficacy against fourth-stage larvae, 20 domestic shorthair cats were inoculated with 500 embryonated eggs. Four weeks after inoculation, the animals were allocated to two groups, and cats in one group were treated with medicated tablets containing 4 mg milbemycin oxime and 10mg praziquantel (MILBEMAX) and cats in the other group with placebo tablets. Seven days after treatment the animals were euthanatized and necropsied for worm counting. The number of worms found was significantly (p=0.0002) lower in cats treated with medicated tablets than in cats treated with placebo tablets. The reduction in the number of worms was 96.53%. In the study to determine efficacy against mature adult worms, 13 kittens were inoculated with T. cati embryonated eggs. On day 45 after inoculation and after the infection had been confirmed through faecal examinations for 11 out of the 13 animals, the 11 infected animals were allocated to two groups and treated as in the first study. Seven days after treatment, all animals were euthanatized and necropsied for worm counting. The number of worms found was significantly (p=0.0043) lower in kittens treated with medicated tablets than in kittens treated with placebo tablets. The reduction in the number of worms was 95.90%. No adverse effects were recorded during either study. It is concluded that the milbemycin oxime-praziquantel tablets that were used are efficacious for the control of T. cati infections in cats. 相似文献
33.
Femtosecond laser pulses and coherent two-phonon Raman scattering were used to excite KTaO3 into a squeezed state, nearly periodic in time, in which the variance of the atomic displacements dips below the standard quantum limit for half of a cycle. This nonclassical state involves a continuum of transverse acoustic modes that leads to oscillations in the refractive index associated with the frequency of a van Hove singularity in the phonon density of states. 相似文献
34.
Jonathan N. King Mike Martin Valrie Chetboul Luca Ferasin Anne T. French Günther Strehlau Wolfgang Seewald Sarah G. W. Smith Simon T. Swift Susan L. Roberts Andrea M. Harvey Christopher J. L. Little Sarah M. A. Caney Kerry E. Simpson Andrew H. Sparkes Eleanor J. Mardell Eric Bomassi Claude Muller John P. Sauvage Armelle Diqulou Matthias A. Schneider Laurence J. Brown David D. Clarke Jean‐Francois Rousselot 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2019,33(6):2559-2571
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B.C. Hosking D.P. Dobson P.A. Stein R. Kaminsky B. Bapst D. Mosimann P.C. Mason W. Seewald G. Strehlau H. Sager 《Veterinary parasitology》2009,160(3-4):251-257
Monepantel is the first compound from the recently discovered amino-acetonitrile derivative (AAD) class of anthelmintics to be developed for use in sheep. Nine dose confirmation studies were conducted in Australia, New Zealand and Switzerland to confirm the minimum therapeutic oral dose of monepantel to control fourth stage (L4) gastro-intestinal nematode larvae in sheep (target species were Haemonchus contortus, Teladorsagia (Ostertagia) circumcincta, Teladorsagia trifurcata, Trichostrongylus axei, Trichostrongylus colubriformis, Trichostrongylus vitrinus, Cooperia curticei, Cooperia oncophora, Nematodirus battus, Nematodirus filicollis, Nematodirus spathiger, Chabertia ovina and Oesophagostomum venulosum). In each study, sheep infected with a defined selection of the target nematodes were treated with 2.5 mg monepantel/kg liveweight. Following euthanasia and worm counting, efficacy was calculated against worm counts from untreated control groups. The results demonstrate high (95 < 100%) efficacy of monepantel when administered orally to sheep at 2.5 mg/kg for most species tested. Efficacy levels against N. spathiger and O. venulosum were variable and failed to meet the required regulatory standard (≥90%) in some studies. Efficacy was demonstrated against L4 stages of nematodes known to be resistant to either benzimidazole and/or levamisole anthelmintics (macrocyclic lactone resistant isolates were not available for testing). The broad-spectrum activity of monepantel against L4 larvae of common gastro-intestinal nematodes in sheep and its favorable safety profile represents a significant advance in the treatment of parasitic gastro-enteritis in this animal species. No adverse effects related to treatment with monepantel were observed. 相似文献
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[目的]为研究饲料中添加小苏打对甘南地区荷斯坦牛产奶量的影响。[方法]选用27头健康、年龄、泌乳期一致的荷斯坦牛27头,随机分为3组,每组9头,设为对照组、试验A组、试验B组。分别饲喂8 kg青干草1、kg马铃薯;配合精料(见表2);配合精料(见表2)+150 g小苏打。[结果]试验A、B组比对照组日均多产奶3.75 kg和4.3 kg,分别提高了28%和32.1%(P〈0.05),差异显著,试验B组较A组提高了0.55 kg(P〉0.05),差异不显著。试验A、B组比对照组日均毛收入提高了7.53和9.65元,试验B组较A组日均毛收入提高了2.12元。[结论]在荷斯坦牛饲料中添加150 g小苏打能有效提高产奶量。 相似文献
40.
通过对欧山F1和山谷型藏羊羔羊进行屠宰试验,结果得出:9月龄欧山F1羔羊宰前平均活重为38.25 kg,比本地山谷型藏羊羔羊宰前平均活重高10.17 kg,差异极显著(P<0.01)。欧山F1羔羊胴体重和屠宰率分别为15.14 kg和39.58%,比对照组高4.58 kg(P<0.01)和1.96个百分点,差异极显著。欧山F1羔羊净肉率、后腿比例和腰肉比例分别为29.65%、38.18%和12.99%,高于山谷型藏羊4.01、7.78和2.68个百分点;欧山F1羔羊GR值和眼肌面积分别为8.23 mm和12.74 cm2,高于山谷型藏羊1.48 mm和4.38 cm2。 相似文献