Genetic manipulation in potato withAgrobacterium rhizogenes     

G. Ooms  M. E. Bossen  M. M. Burrell  A. Karp 《Potato Research》1986,29(3):367-379

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Rabies in two privately owned domestic rabbits     

Karp BE  Ball NE  Scott CR  Walcoff JB 《Journal of the American Veterinary Medical Association》1999,215(12):1824-7, 1806

Two privately owned domestic rabbits (Oryctolagus cuniculus) in Maryland were found to be infected with the raccoon variant of the rabies virus in 1998. Both rabbits had an acute onset of anorexia and paralysis or paresis of the left forelimb; 1 also developed head tremors and a head tilt. One of the rabbits became ill 25 days after being attacked by a raccoon (Procyon lotor) and was euthanatized 3 days after onset of illness. The other rabbit, which was housed in an outdoor hutch, died 4 days after onset of clinical signs; the source of infection in that rabbit remains unknown. Currently, there is not a rabies vaccine approved for use in rabbits; thus, the only way to prevent the infection in rabbits is to prevent exposure. Veterinarians in rabies-enzootic areas should be familiar with the clinical signs of rabies in rabbits and should caution rabbit owners about the need to protect their pets from contact with wildlife.  相似文献   

Somaclonal variation as a tool for crop improvement     

Angela Karp 《Euphytica》1955,85(1-3):295-302

Summary Somaclonal variation is a tool that can be used by plant breeders. The review examines where this tool can be applied most effectively and the factors that limit or improve its chances of success. The main factors that influence the variation generated from tissue culture are (1) the degree of departure from organised growth, (2) the genotype, (3) growth regulators and (4) tissue source. Despite an increasing understanding of how these factors work it is still not possible to predict the outcome of a somaclonal breeding programme. New varieties have been produced by somaclonal variation, but in a large number of cases improved variants have not been selected because (1) the variation was all negative, (2) positive changes were also altered in negative ways, (3) the changes were not novel, or (4) the changes were not stable after selfing or crossing. Somaclonal variation is cheaper than other methods of genetic manipulation. At the present time, it is also more universally applicable and does not require containment procedures. It has been most successful in crops with limited genetic systems and/or narrow genetic bases, where it can provide a rapid source of variability for crop improvement.  相似文献   

Denver earthquakes     

Karp E  Simon RB 《Science (New York, N.Y.)》1970,167(3924):1518-1519

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Consumer Versus Resource Control in Freshwater Pelagic Food Webs     

MT Brett  CR Goldman 《Science (New York, N.Y.)》1997,275(5298):384-386

Models predict that food-web structure is regulated by both consumers and resources, and the strength of this control is dependent on trophic position and food-web length. To test these hypotheses, a meta-analysis was conducted of 11 fish (consumer)-by-nutrient (resource) factorial plankton community experiments. As predicted, zooplankton biomass was under strong consumer control but was weakly stimulated by nutrient additions; phytoplankton biomass was under strong resource control with moderate control by fish. However, the phytoplankton and zooplankton responses to nutrient additions did not follow theoretical predictions based on the number of trophic levels in the food web.  相似文献   

Detection of traces of tetracyclines from fish with a bioluminescent sensor strain incorporating bacterial luciferase reporter genes   总被引：3，自引：0，他引：3  

Pellinen T  Bylund G  Virta M  Niemi A  Karp M 《Journal of agricultural and food chemistry》2002,50(17):4812-4815

Bioluminescent Escherichia coli K-12 strain for the specific detection of the tetracycline family of antimicrobial agents was optimized to work with fish samples. The biosensing strain contains a plasmid incorporating the bacterial luciferase operon of Photorhabdus luminescens under the control of the tetracycline responsive element from transposon Tn10 (Korpela et al. Anal. Chem. 1998, 70, 4457-4462). The extraction procedure of oxytetracycline from rainbow trout (Oncorhynchus mykiss) tissue was optimized. There was neither need for centrifugation of homogenized tissue nor use of organic solvents. The lowest levels of detection of tetracycline and oxytetracycline from spiked fish tissue were 20 and 50 microg/kg, respectively, in a 2-h assay. The optimized assay protocol was tested with fish that were given a single oral dose of high and low concentrations of oxytetracycline. The assay was able to detect oxytetracycline residues below the European Union maximum residue limits, and the results correlated well with those obtained by conventional HPLC (R = 0.81).  相似文献   

Evaluation of a regimen using a progesterone releasing intravaginal device (CIDR) and PMSG as a treatment for post partum anoestrus in dairy cattle     

TF. JUBB  P. BRIGHTLING  J. MALMO†  MT. LARCOMBE  GA. ANDERSON  SJ. HIDES‡ 《Australian veterinary journal》1989,66(10):334-336

Anoestrous dairy cows in seasonally calving herds in the Macalister Irrigation District of Gippsland, Victoria were treated at the start of the mating period with a progesterone releasing intravaginal device (CIDR). The CIDR was inserted for 7 days and 400 IU of PMSG was injected intramuscularly at removal. There was no clinically useful difference among cows receiving the CIDR, a placebo and untreated cows in the interval from treatment to either first oestrus or conception, the conception rate to first service or percent pregnant by the end of mating. Analyses of data from 2-year-old cows, older cattle, cows calved at least 45 days or cows calved at least 55 days and cows treated 3 weeks after the start of mating did not show improved reproductive performance following treatment with the CIDR.  相似文献   

Intrauterine Idiopathic Amputation of the Head of a Porcine Foetus     

JS Agerholm  MT Garoussi 《Reproduction in domestic animals》2013,48(3):e38-e40

An anencephalic full‐term porcine foetus accompanied by a mummified head was submitted for examination. The neck almost entirely lacked skin and was covered by granulation tissue as were the exposed parts of the spine and spinal cord. The case represents a rare case of intrauterine amputation. A definitive cause could not be established because the placenta was not available. The most likely cause is strangulation of the neck. Such strangulation could be due to a defect of the allantoamnion with herniation of the foetal head or entanglement by amniotic constriction bands.  相似文献   

Rapid detection of tetracyclines and their 4-epimer derivatives from poultry meat with bioluminescent biosensor bacteria     

Virolainen NE  Pikkemaat MG  Elferink JW  Karp MT 《Journal of agricultural and food chemistry》2008,56(23):11065-11070

Tetracycline (TC) specific luminescent bacterial biosensors were used in a rapid TC residue assay sensitized to meet the EU maximum residue limit (MRL) for TC residues in poultry muscle tissue (100 microg kg(-1)) by membrane-permeabilizing and chelating agents polymyxin B and EDTA. Sensitivities of 5 ng g(-1) for doxycycline, 7.5 ng g(-1) for chlortetracycline, and 25 ng g(-1) for tetracycline and oxytetracycline were reached. Except for doxycycline, the MRLs of these tetracyclines include their 4-epimer metabolites. In the biosensor assay, all four 4-epimers showed induction capacity and antimicrobial activity, and antimicrobial activity was also observed in the inhibition assay, although with lower efficiency than that of the corresponding parent compound in both assays. The biosensor assay is an inexpensive and rapid high-throughput screening method for the detection of 4-epimer TC residues along with their parent compounds.  相似文献   

Identification and geographical distribution of pyrethroid resistance mutations in the poultry red mite Dermanyssus gallinae     

Evangelia Katsavou  Spyros Vlogiannitis  Eleanor Karp‐Tatham  Damer P Blake  Aris Ilias  Christina Strube  Ilias Kioulos  Wannes Dermauw  Thomas Van Leeuwen  John Vontas 《Pest management science》2020,76(1):125-133

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