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31.
Twelve adult cattle were electrically stunned head-only (400 V, 2.5 A, 50 Hz) behind the ears for four seconds. Within ten seconds of stun initiation, the carotid arteries, jugular veins, trachea and oesophagus were severed. Twenty seconds after the stun initiation, ten animals received an electro-immobilization current (80 V peak, 14.3 Hz, 5 ms square wave, 300 mA) nose to anus for periods ranging from 30-37 seconds. Electroencephalographic (EEG) traces were recorded before and after the stun up until electroimmobilization and at cessation of electro-immobilization by means of implanted electrodes, and animal movement was recorded on videotape. Before the stun, the EEG trace was within a window of sensibility (10-40 microV amplitude). During the stun, the amplitude increased and sometimes exceeded 500 microV. At the end of electro-immobilization, EEG amplitude was less than 10 microV, indicating insensibility. This amplitude was reached in the two non-immobilized animals 57 seconds and 63 seconds after stun initiation. During stunning, the forelegs and hindlegs usually tucked under the animals. Various degrees of foreleg extension then occurred. From about ten seconds post-stun, paddling movements occurred, at which time the EEG trace showed large-amplitude waves characteristic of a stunned animal. During immobilization, the animals stiffened and breathing stopped. After immobilization weak muscle spasms occurred that did not interfere with dressing operations. Non-immobilized animals moved excessively, inhibiting dressing. It is concluded that adult cattle rendered insensible by stunning do not recover sensibility during the stun/throat-cut/immobilization operation and therefore this procedure is humane. 相似文献
32.
High-resolution measurements of the kinetic energies of hydrogen atom fragments formed during ultraviolet photolysis of imidazole, pyrrole, and phenol in the gas phase confirm that N(O)-H bond fission is an important nonradiative decay process from their respective 1pisigma* excited states. The measurements also reveal that the respective cofragments (imidazolyl, pyrrolyl, and phenoxyl) are formed in very limited subsets of their available vibrational states. Identification of these product states yields uniquely detailed insights into the vibronic couplings involved in the photoinduced evolution from parent molecule to ultimate fragments. 相似文献
33.
Buescher JM Liebermeister W Jules M Uhr M Muntel J Botella E Hessling B Kleijn RJ Le Chat L Lecointe F Mäder U Nicolas P Piersma S Rügheimer F Becher D Bessieres P Bidnenko E Denham EL Dervyn E Devine KM Doherty G Drulhe S Felicori L Fogg MJ Goelzer A Hansen A Harwood CR Hecker M Hubner S Hultschig C Jarmer H Klipp E Leduc A Lewis P Molina F Noirot P Peres S Pigeonneau N Pohl S Rasmussen S Rinn B Schaffer M Schnidder J Schwikowski B Van Dijl JM Veiga P Walsh S Wilkinson AJ Stelling J Aymerich S 《Science (New York, N.Y.)》2012,335(6072):1099-1103
34.
Moho offset across the northern margin of the tibetan plateau 总被引:9,自引:0,他引:9
Anomalous double-pulse teleseismic P-wave arrivals were observed at one station near the northern margin of the Tibetan Plateau. The azimuthal dependence of the waveform distortion and its absence at nearby stations indicated that the distortion was produced by receiver-side crustal heterogeneity. Modeling of the three-component data revealed a 15- to 20-kilometer Moho offset that occurs over a narrow lateral range of less than 5 kilometers. This east-west-striking offset separates the thick Tibetan Plateau crust from the Qaidam Basin crust. Such a sharp crustal thickness change implies a weak Tibetan Plateau crust that thickens vertically in response to penetration by India from the south and to blockage caused by a strong Qaidam Basin crust to the north. 相似文献
35.
J. J. Bass B.Sc. Ph.D. A. J. Peterson B.Sc. Ph.D. C. E. Devine B.Sc. Ph.D. 《Australian veterinary journal》1976,52(11):517-518
Ninety bull calves were made cryptorchid by forcing the testes into the abdominal cavity and ablating the scrotum with elastrator rings. Normal spermatogenesis was seen following histological examination of some of the testes approximately 17 months after the operation. No effect on bull behaviour was noted in the cryptorchids although plasma testosterone levels were lower than those reported for bulls. It is possible that this method may leave some of the cryptorchids fertile. 相似文献
36.
Devine MD 《Pest management science》2005,61(3):312-317
Herbicide-tolerant (HT) varieties of corn, soybean, canola (oilseed rape) and cotton have been grown since the mid-1990s, and have been widely adopted by farmers in several countries. HT genes have been inserted into or selected for in many other species, including almost all major crop species in the world and many minor crops and ornamental species. In some cases this has been done specifically to introduce the HT trait, whereas in others the HT gene has been used as a selectable marker (eg the bar gene, conferring glufosinate-ammonium tolerance). However, in very few cases have the HT crops generated been commercialized, despite the weed-control advantages that many such crops would offer. There are several reasons for this, including the high research and development costs associated with developing the new HT crop cultivars, the high cost of obtaining regulatory clearance for the HT crops or products derived from them, international trade issues relating to genetically modified crops, and issues surrounding the expanded herbicide registration for the new use and the potential impact of this on the existing registration status of the herbicide. New HT crops are unlikely to be developed unless they offer a sufficiently large advantage to farmers and a substantial assured market to justify the associated development and regulatory costs. 相似文献
37.
Cranial tibial thrust: a primary force in the canine stifle 总被引:5,自引:0,他引:5
A cranially directed force identified within the canine stifle joint was termed cranial tibial thrust. It was generated during weight bearing by tibial compression, of which the tarsal tendon of the biceps femoris is a major contributor, and by the slope of the tibial plateau, found to have a mean cranially directed inclination of 22.6 degrees. This force may be an important factor in cranial cruciate ligament rupture and in generation of cranial drawer sign. 相似文献
38.
Altered target sites as a mechanism of herbicide resistance 总被引:4,自引:0,他引:4
Over 200 distinct herbicide resistant weed biotypes have evolved worldwide. In most of these, resistance is conferred by an altered target site, i.e. a modified target protein with reduced affinity for the herbicide(s) in question. This has been documented for herbicides that target most major known sites of action, including those that inhibit photosynthetic electron transfer at photosystem II, acetyl-CoA carboxylase, acetolactate synthase, and tubulin polymerization. Patterns of cross-resistance to structurally similar herbicides and those from other chemical classes that target the same site vary, depending on the mutation and its effect on protein steric and electronic properties. Mechanisms of target site-based herbicide resistance are reviewed, with emphasis on the biochemical and molecular basis for resistance. 相似文献
39.
Shukla A Nycholat C Subramanian MV Anderson RJ Devine MD 《Journal of agricultural and food chemistry》2004,52(16):5144-5150
The aryloxyphenoxypropionic acid (AOPP) and cyclohexanedione (CHD) herbicides inhibit the first committed enzyme in fatty acid biosynthesis, acetyl CoA carboxylase (ACCase). The frequent use of AOPP and CHD herbicides has resulted in the development of resistance to these herbicides in many grass weed species. New herbicides that inhibit both the susceptible and resistant forms of ACCase in grass weeds would have obvious commercial appeal. In the present study, an attempt was made to identify molecules that target both the herbicide-sensitive and -resistant forms of ACCase. Seven experimental compounds, either CHD-like or AOPP-CHD hybrids, were synthesized and assayed against previously characterized susceptible and resistant forms of ACCase. All seven compounds inhibited ACCase from sensitive biotypes of Setaria viridis and Eleusine indica (I50 values from 6.4 to >100 microM) but were not particularly potent compared to some commercialized herbicides (I50 values of 0.08-5.6 microM). In almost all cases, the I50 values for each compound assayed against the resistant ACCases were higher than those against the corresponding sensitive ACCase, indicating reduced binding to the resistant ACCases. One compound, a CHD analogue, was almost equally effective against the resistant and susceptible ACCases, although it was not a very potent ACCase inhibitor per se (I50 of 51 and 76 microM against susceptible ACCase from S. viridis and E. indica, respectively). The AOPP-CHD hybrid molecules also inhibited some of the resistant ACCases, with I50 values ranging from 6.4 to 50 microM. These compounds may be good leads for developing ACCase inhibitors that target a wider range of ACCase isoforms, including those found in AOPP- and CHD-resistant weed biotypes. 相似文献
40.
Ronan A. Mullins MVB DECVS Carlos Sanchez Villamil DVM Laura E. Selmic BVetMed MPH DACVS-SA DECVS Michael S. Tivers BVSc PhD DECVS J. Brad Case DVM MS DACVS Ameet Singh BSc DVM DVSc DACVS Kelley M. Thieman Mankin DVM MS DACVS Davina M. Anderson MA VetMB PhD DSAS DECVS Robert N. White BSc BVetMed DSAS DECVS SFHEA Kathryn M. Pratschke MVB MVM DECVS Hilde de Rooster DVM MVM PhD DECVS Anne Kummeling DVM PhD DECVS Donald A. Yool BVMS PhD DECVS SFHEA Melanie Olive DVM Jean-Philippe Billet Dr vét DECVS Ines Gordo DVM MS Herve Brissot DV DECVS Cameron Broome BVSc DVCS FANZCVS Barbara M. Kirby DVM MS DACVS DECVS 《Veterinary surgery : VS》2020,49(5):958-970