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151.
Effects of Age and Pretreatment of Tissue-Cultured Potato Plants on Subsequent Minituber Production 总被引:1,自引:0,他引:1
Mirko Milinkovic Corina B. Horstra Brendan C. Rodoni Marc E. Nicolas 《Potato Research》2012,55(1):15-25
Potato (Solanum tuberosum L.) plantlets were conditioned in tissue culture to produce more minitubers when planted in a greenhouse. Tissue-cultured
potato plantlets, varieties Coliban and Russet Burbank, were grown for 4, 10, or 12 weeks under three temperature regimes
(22/18 °C, 16/10 °C, and 10/2 °C day/night) and a photoperiod of 16, 12, or 8 h in different stages of growth. Duration, temperature,
and photoperiod of the in vitro period affected plantlet morphology and the total number of minitubers produced per plant
in a greenhouse. Extending the growing period and introducing a hardening period with low temperatures (16/10 °C) during the
in vitro production stage resulted in 97% more minitubers (4.94 vs 2.50 minitubers per plant for the control) in variety Coliban
and up to 71% (6.50 vs 3.80 minitubers per plant for the control) in variety Russet Burbank. The total number of minitubers
produced per plant did not change significantly for both varieties when a shorter photoperiod was used instead of the standard
16-h day during the growing period in vitro. Results presented in this experiment demonstrate that the number of minitubers
can be substantially increased through the introduction of an induction period as an interstage between the in vitro stages
of potato plantlet production and minituber production. 相似文献
152.
Alessandro Busetti Thomas P. Thompson Diana Tegazzini Julianne Megaw Christine A. Maggs Brendan F. Gilmore 《Marine drugs》2015,13(6):3581-3605
The marine brown alga Halidrys siliquosa is known to produce compounds with antifouling activity against several marine bacteria. The aim of this study was to evaluate the antimicrobial and antibiofilm activity of organic extracts obtained from the marine brown alga H. siliquosa against a focused panel of clinically relevant human pathogens commonly associated with biofilm-related infections. The partially fractionated methanolic extract obtained from H. siliquosa collected along the shores of Co. Donegal; Ireland; displayed antimicrobial activity against bacteria of the genus Staphylococcus; Streptococcus; Enterococcus; Pseudomonas; Stenotrophomonas; and Chromobacterium with MIC and MBC values ranging from 0.0391 to 5 mg/mL. Biofilms of S. aureus MRSA were found to be susceptible to the algal methanolic extract with MBEC values ranging from 1.25 mg/mL to 5 mg/mL respectively. Confocal laser scanning microscopy using LIVE/DEAD staining confirmed the antimicrobial nature of the antibiofilm activity observed using the MBEC assay. A bioassay-guided fractionation method was developed yielding 10 active fractions from which to perform purification and structural elucidation of clinically-relevant antibiofilm compounds. 相似文献
153.
Schultz PH Hermalyn B Colaprete A Ennico K Shirley M Marshall WS 《Science (New York, N.Y.)》2010,330(6003):468-472
As its detached upper-stage launch vehicle collided with the surface, instruments on the trailing Lunar Crater Observation and Sensing Satellite (LCROSS) Shepherding Spacecraft monitored the impact and ejecta. The faint impact flash in visible wavelengths and thermal signature imaged in the mid-infrared together indicate a low-density surface layer. The evolving spectra reveal not only OH within sunlit ejecta but also other volatile species. As the Shepherding Spacecraft approached the surface, it imaged a 25- to-30-meter-diameter crater and evidence of a high-angle ballistic ejecta plume still in the process of returning to the surface--an evolution attributed to the nature of the impactor. 相似文献
154.
Bach JE Kukanich B Papich MG McKiernan BC 《Journal of the American Veterinary Medical Association》2004,224(7):1113-1119
OBJECTIVE: To evaluate the bioavailability and pharmacokinetic characteristics of 2 commercially available extended-release theophylline formulations in dogs. DESIGN: Randomized 3-way crossover study. ANIMALS: 6 healthy adult dogs. PROCEDURE: A single dose of aminophylline (11 mg x kg(-1) 15 mg x lb(-1)], i.v., equivalent to 8.6 mg of theophylline/kg 13.9 mg x lb(-1) or extended-release theophylline tablets (mean dose, 15.5 mg x kg(-1) [7.04 mg x lb9-1), PO) or capsules (mean dose, 15.45 mg x kg(-1) [7.02 mg x lb(-1)], PO) was administered to all dogs. Blood samples were obtained at various times for 36 hours after dosing; plasma was separated and immediately frozen. Plasma samples were analyzed by use of fluorescence polarization immunoassay. RESULTS: Administration of theophylline i.v. best fit a 2-compartment model with rapid distribution followed by slow elimination. Administration of extended-release theophylline tablets and capsules best fit a 1-compartment model with an absorption phase. Mean values for plasma terminal half-life, volume of distribution, and systemic clearance were 8.4 hours, 0.546 L x kg(-1), and 0.780 mL x kg(-1) x min(1), respectively, after i.v. administration of theophylline. Systemic availability was > 80% for both oral formulations. Computer simulations predicted that extended-release theophylline tablets or capsules administered at a dosage of 10 mg x kg(-1) (4.5 mg x lb(-1)), PO, every 12 hours would maintain plasma concentrations within the desired therapeutic range of 10 to 20 microg x mL(-10. CONCLUSIONS AND CLINICAL RELEVANCE: Results of these single-dose studies indicated that administration of the specific brand of extended-release theophylline tablets or capsules used in this study at a dosage of 10 mg x kg(-1), PO, every 12 hours would maintain plasma concentrations within the desired therapeutic range (10 to 20 microg x mL(-1)) in healthy dogs. 相似文献
155.
Abutarbush SM Carmalt JL Wilson DG O'Connor BP Clark EG Naylor JM 《The Canadian veterinary journal. La revue veterinaire canadienne》2004,45(1):48-50
Two beef cows were presented with a history of anorexia and abdominal pain. Both cows were euthanized. Necropsy revealed the presence of a segmental area of ulceration, necrosis, and intraluminal blood clots in the jejunum. Jejunal hemorrhage syndrome is an emerging disease and has not been reported previously in beef cattle. 相似文献
156.
Surveillance for porcine proliferative enteropathy in Alberta by using routine diagnostic laboratory data 下载免费PDF全文
Wilson JB Honour S Pauling GE O'Connor B Benjamin M Paradis MA Dick CP 《The Canadian veterinary journal. La revue veterinaire canadienne》2002,43(8):604-606
Data from the Food Safety Division, Alberta Agriculture, Food and Rural Development were analyzed to determine the frequency of diagnosis of porcine proliferative enteropathy (PPE) relative to the diagnosis of other porcine enteric infections between 1993 and 1997. Next to colibacillosis, PPE was the most commonly diagnosed enteric disease among those reported. 相似文献
157.
We installed 12 pond levelers to counter flooding by beavers and developed a cost–benefit analysis for these sites in Alberta, Canada. We also documented beaver management approaches throughout Alberta. Over 3 years, one site required regular maintenance until we designed a modified pond leveler; another required minor modifications. Others required almost no maintenance. Based on a “willingness-to-pay” (WTP) of $0 and discount rate of 3%, installing pond levelers resulted in a present value net benefit of $81,519 over 3 years and $179,440 over 7 years. Scenarios incorporating discount rates of 3% and 7%, horizons of either 3 or 7 years, and varying WTPs resulted in significant net benefits. Provincially, municipalities employed up to seven methods to control beavers: most commonly lethal control and dam removal. Total annual costs provided by 48 municipalities and 4 provincial parks districts were $3,139,223; however, cost-accounting was sometimes incomplete, which makes this a conservative estimate. 相似文献
158.
Nene V Wortman JR Lawson D Haas B Kodira C Tu ZJ Loftus B Xi Z Megy K Grabherr M Ren Q Zdobnov EM Lobo NF Campbell KS Brown SE Bonaldo MF Zhu J Sinkins SP Hogenkamp DG Amedeo P Arensburger P Atkinson PW Bidwell S Biedler J Birney E Bruggner RV Costas J Coy MR Crabtree J Crawford M Debruyn B Decaprio D Eiglmeier K Eisenstadt E El-Dorry H Gelbart WM Gomes SL Hammond M Hannick LI Hogan JR Holmes MH Jaffe D Johnston JS Kennedy RC Koo H Kravitz S Kriventseva EV Kulp D Labutti K Lee E Li S Lovin DD 《Science (New York, N.Y.)》2007,316(5832):1718-1723
We present a draft sequence of the genome of Aedes aegypti, the primary vector for yellow fever and dengue fever, which at approximately 1376 million base pairs is about 5 times the size of the genome of the malaria vector Anopheles gambiae. Nearly 50% of the Ae. aegypti genome consists of transposable elements. These contribute to a factor of approximately 4 to 6 increase in average gene length and in sizes of intergenic regions relative to An. gambiae and Drosophila melanogaster. Nonetheless, chromosomal synteny is generally maintained among all three insects, although conservation of orthologous gene order is higher (by a factor of approximately 2) between the mosquito species than between either of them and the fruit fly. An increase in genes encoding odorant binding, cytochrome P450, and cuticle domains relative to An. gambiae suggests that members of these protein families underpin some of the biological differences between the two mosquito species. 相似文献
159.
Abutarbush SM O'Connor BP Clark C Sampieri F Naylor JM 《The Canadian veterinary journal. La revue veterinaire canadienne》2004,45(4):315-317
Two horses had a history of ataxia and weakness or recumbency. One recovered and was diagnosed with West Nile virus (WNV) infection by serologic testing. The other was euthanized; it had meningoencephalomyelitis, WNV was detected by polymerase chain reaction. West Nile virus infection is an emerging disease. Year 2002 is the first year in which cases have been seen in Saskatchewan. 相似文献