Baylisascaris larva migrans   总被引：4，自引：0，他引：4  

K R Kazacos  W M Boyce 《Journal of the American Veterinary Medical Association》1989,195(7):894-903

  相似文献   

The preservation of Brucella melitensis Rev. I vaccine     

W J Morgan  K J Boyce  A D Casey 《Research in veterinary science》1970,11(3):285-287

  相似文献   

Comparative properties of N-acetyl derivatives of oxime N-methylcarbamates and aryl N-methylcarbamates as insecticides and acetylcholinesterase inhibitors     

J. J. K. Boulton  C. B. C. Boyce  P. J. Jewess  R. F. Jones 《Pest management science》1971,2(1):10-15

N-acylation of aryl N-methylcarbamates is known to reduce their mammalian toxicity considerably without adversely affecting their insecticidal activity. It has now been found that N-acylation of several insecticidal oxime carbamates results in loss of toxicity both to insects and mammals. Kinetic data for base-catalysed solvolysis and inhibition of acetylcholinesterase, together with published work on metabolism, are combined to provide a rationale for this unexpected observation and to account for the selective toxicity of aryl N-acetyl-N-methylcarbamates.  相似文献   

Complication after the use of a combination of lignocaine and xylazine for epidural anaesthesia in a mare     

JB CHOPIN  JD WRIGHT 《Australian veterinary journal》1995,72(9):354-355

  相似文献   

The effect of fertility control on the transmission of bovine tuberculosis in wild brushtail possums     

DSL Ramsey  JD Coleman  MC Coleman  P Horton 《New Zealand veterinary journal》2013,61(5):218-223

AIM: To determine the effect of fertility control on the rate of transmission of bovine tuberculosis (Tb), caused by Mycobacterium bovis, in brushtail possums (Trichosurus vulpecula).

METHODS: At two study sites with a history of Tb infection in the resident possum population, a sample of adult male and female possums (n=50), determined by palpation to be Tb-free, was surgically sterilised by gonadectomy. A sample of untreated Tb-free male and female possums (n=54) served as controls. Each study site was trapped every 2 months over a 3-year period, and the Tb status of the individuals in the trial assessed. At the conclusion of the trial, all remaining experimental individuals were killed, necropsied and examined for characteristic lesions typical of Tb. The rate of transmission of Tb infection was estimated using the incidence of tuberculous cases in the experimental animals and comparing it between sites, sex and sterilisation treatment.

RESULTS: Sterilisation by gonadectomy resulted in a reduction in the rate of transmission of Tb in male possums by 53%, but a corresponding increase in sterilised females for reasons that are still unclear. However, this interaction was statistically weak (p=0.10). When the sexes were combined, there was no overall effect of sterilisation on the rate of transmission of Tb (p=0.43). Sterility treatment notwithstanding, there was a highly significant difference in the rate of transmission between the sexes (p=0.01), being almost one order of magnitude higher in untreated males compared with untreated females.

CONCLUSIONS: Although lacking strong statistical support, these results suggest that fertility control that targets endocrine control of fertility may provide some additional benefits for disease control over that achieved by reductions in population density, by reducing the rate of transmission of M. bovis in male possums. However, additional studies are needed to confirm the validity of these results. The large difference in the rate of transmission of M. bovis in untreated males compared with untreated females suggests that transmission of Tb among males may be an important driver of the dynamics of Tb infection in possums.  相似文献   

Hypoventilation,cardiac dysrhythmia,and cardiac arrest following acute Brunfelsia species (Yesterday,today, tomorrow) intoxication in a dog     

JD Crowley  KA Thomas  SL Donahoe  G Child  MC Hickey  ET Mooney 《Australian veterinary journal》2019,97(6):202-207

  相似文献   

A dielectric omnidirectional reflector   总被引：3，自引：0，他引：3  

Y Fink  JN Winn  S Fan  C Chen  J Michel  JD Joannopoulos  EL Thomas 《Science (New York, N.Y.)》1998,282(5394):1679-1682

A design criterion that permits truly omnidirectional reflectivity for all polarizations of incident light over a wide selectable range of frequencies was used in fabricating an all-dielectric omnidirectional reflector consisting of multilayer films. The reflector was simply constructed as a stack of nine alternating micrometer-thick layers of polystyrene and tellurium and demonstrates omnidirectional reflection over the wavelength range from 10 to 15 micrometers. Because the omnidirectionality criterion is general, it can be used to design omnidirectional reflectors in many frequency ranges of interest. Potential uses depend on the geometry of the system. For example, coating of an enclosure will result in an optical cavity. A hollow tube will produce a low-loss, broadband waveguide, whereas a planar film could be used as an efficient radiative heat barrier or collector in thermoelectric devices.  相似文献   

Femtosecond dynamics of electron localization at interfaces     

N Ge  CM Wong  RL Lingle  JD McNeill  KJ Gaffney  CB Harris 《Science (New York, N.Y.)》1998,279(5348):202-205

The dynamics of two-dimensional small-polaron formation at ultrathin alkane layers on a silver(111) surface have been studied with femtosecond time- and angle-resolved two-photon photoemission spectroscopy. Optical excitation creates interfacial electrons in quasi-free states for motion parallel to the interface. These initially delocalized electrons self-trap as small polarons in a localized state within a few hundred femtoseconds. The localized electrons then decay back to the metal within picoseconds by tunneling through the adlayer potential barrier. The energy dependence of the self-trapping rate has been measured and modeled with a theory analogous to electron transfer theory. This analysis determines the inter- and intramolecular vibrational modes of the overlayer responsible for self-trapping as well as the relaxation energy of the overlayer molecular lattice. These results for a model interface contribute to the fundamental picture of electron behavior in weakly bonded solids and can lead to better understanding of carrier dynamics in many different systems, including organic light-emitting diodes.  相似文献   

A long-snouted predatory dinosaur from africa and the evolution of spinosaurids     

PC Sereno  AL Beck  DB Dutheil  B Gado  HCE Larsson  GH Lyon  JD Marcot  OWM Rauhut  RW Sadleir  CA Sidor  DD Varricchio  GP Wilson  JA Wilson 《Science (New York, N.Y.)》1998,282(5392):1298-1302

Fossils discovered in Lower Cretaceous (Aptian) rocks in the Tenere Desert of central Niger provide new information about spinosaurids, a peculiar group of piscivorous theropod dinosaurs. The remains, which represent a new genus and species, reveal the extreme elongation and transverse compression of the spinosaurid snout. The postcranial bones include blade-shaped vertebral spines that form a low sail over the hips. Phylogenetic analysis suggests that the enlarged thumb claw and robust forelimb evolved during the Jurassic, before the elongated snout and other fish-eating adaptations in the skull. The close phylogenetic relationship between the new African spinosaurid and Baryonyx from Europe provides evidence of dispersal across the Tethys seaway during the Early Cretaceous.  相似文献   

Tracking the long-term decline and recovery of an isolated population     

RL Westemeier  JD Brawn  SA Simpson  TL Esker  RW Jansen  JW Walk  EL Kershner  JL Bouzat  KN Paige 《Science (New York, N.Y.)》1998,282(5394):1695-1698

Effects of small population size and reduced genetic variation on the viability of wild animal populations remain controversial. During a 35-year study of a remnant population of greater prairie chickens, population size decreased from 2000 individuals in 1962 to fewer than 50 by 1994. Concurrently, both fitness, as measured by fertility and hatching rates of eggs, and genetic diversity declined significantly. Conservation measures initiated in 1992 with translocations of birds from large, genetically diverse populations restored egg viability. Thus, sufficient genetic resources appear to be critical for maintaining populations of greater prairie chickens.  相似文献