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31.
All transgenic cultivars of potatoes registered in Canada and the United States have been modified to express a synthetic cry3A gene as a means of conferring resistance against the Colorado potato beetle, an important economic pest of potatoes. A PCR method was developed to amplify a 499 bp region of the synthetic cry3A gene. Using this method, synthetic cry3A could be detected in six different transgenic cultivars. Positive results could be confirmed with PvuII restriction digestion of the PCR-generated amplicon, which resulted in two fragments that were 283 and 216 bp in size. Of the 52 tuber extracts tested with this method, no false positive or false negative results were obtained, suggesting the method could be used with a high degree of accuracy. The absolute limit of detection was the number of cry3A copies present in one or perhaps two haploid copies of the potato genome. The practical limit of detection in tubers on a fresh weight basis was 0.02% for the NL 10-SUP and 0.01% for the remaining cultivars. Synthetic cry3A could also be detected in processed food products such as potato chips, shoestring potatoes, and frozen French fries. The method was suitable for screening potato tuber lots and some processed foods for the presence of synthetic cry3A. 相似文献
32.
Victor I. Okereke E. Robert Baumann T. Al Austin Donna Schulze Lutz 《Water, air, and soil pollution》1988,37(3-4):325-341
The impact of a flood control, low flow argumentation reservoir in the Midwestern part of the United States on BOD, COD, and ammonia was evaluated in this paper. Fifteen years of weekly water quality data (9 yr before impoundment and 6 yr after impoundment) from four sampling stations upstream and downstream of the reservoir were available for analysis. The annual loading rates of these parameters (kg ha?1 vr?1) were found to correlate well with annual runoff (cm yr?1). Besides, the reservoir was found to have had a significant and beneficial impact on the downstream loading rates of BOD and COD, which were reduced by 55 and 75%, respectively. As for ammonia, the results of this study indicate that its annual loadings at downstream locations were not significantly affected by the reservoir. Average non-point source contributions of BOD and ammonia loadings into the system were found to be about 80 and 55%, respectively. 相似文献
33.
Keld Sorensen PhD Dean P. Neely VMD PhD William Read Paul M. Grappell MD 《Journal of Equine Veterinary Science》1990,10(6):417-421
An assay for the determination of the concentration of an equine fetal protein (EQFP) in pregnant mares serum was developed and used to quantitate more than 2000 serum samples from Thoroughbred mares during pregnancy. The concentration of EQFP increased throughout pregnancy. Mares with unproblematic (normal) pregnancies were used to establish the reference values at given gestational ages (GA). Mares with pregnancy failures (n=58) were found to have EQFP concentrations outside the reference values established at given GA's; 10 were high and 48 were low. Twin pregnancies (n=21), placentitis and impending abortion (n=71) were associated with elevated concentration. Twin pregnancies were detected by elevated EQFP concentration, in one case as early as 12 days after breeding. 相似文献
34.
A modified lateral spinal decompression technique was performed in 61 dogs with thoracolumbar disc protrusion. Myelography combined with plain radiography and neurological examination determined the side of greatest compression in 93 per cent of the dogs. Disc material was retrieved in 98 per cent of the cases. Of the 35 non-ambulatory dogs, 95 per cent regained the ability to walk. The recovery time was three weeks. 相似文献
35.
S M Stover B J Johnson B M Daft D H Read M Anderson B C Barr H Kinde J Moore J Stoltz A A Ardans 《Equine veterinary journal》1992,24(4):260-263
Twenty-one horses had a complete unilateral humeral fracture during race training or racing at a California racetrack during the period 24 February 1990 to 10 July 1991. Fractures occurred approximately equally in left and right limbs, and in males and females. Most fractures occurred during training, and in 2- and 3-year-old horses. Only 5 of 16 Thoroughbred horses with known racing records had previously raced more than once, and their mean time between races was less than the time between their last race and fracture (P = 0.07). Ten of 13 humeri studied further had gross evidence of periosteal callus bridging one portion of the fracture line, indicative of a pre-existing stress fracture. 相似文献
36.
37.
T A Puglisi R W Green C L Hall W K Read R A Green C H Tangner F A Mann H P Hobson 《American journal of veterinary research》1986,47(8):1863-1869
A double-blind study, using metrizamide, iohexol, or Ringer's solution (control) as cisternal myelographic agents, was performed on 25 dogs. Before myelographic examination was done, each dog was subjected to physical, clinical pathologic, and neurologic examinations, as well as examinations by electroencephalography and computerized tomography. These were repeated 24 hours after completion of the myelographic examination. The group of dogs given metrizamide (group II) had a significantly greater occurrence of seizure activity (6 of 10) than did the control dogs (group I; 0 of 5) or dogs given iohexol (group III; 0 of 10; P less than 0.003). In group II, the CSF microprotein concentration was significantly greater 24 hours after myelography was done than were the values in groups I and III (P less than 0.003). Myelograms of the group II dogs (metrizamide) and group III dogs (iohexol) had similar diagnostic qualities. At 24 hours after myelographic examination was done, computerized tomography scan revealed that each dog given metrizamide and iohexol had myelographic contrast material in the brain and cervical spinal cord parenchyma. Seemingly, iohexol has good diagnostic quality, but is less epileptogenic than metrizamide when used in cervical myelographic examinations of dogs. 相似文献
38.
39.
R. A. Read W. T. Reynolds D. J. Griffiths † J. S. Reilly 《Australian veterinary journal》1982,58(6):269-271
SUMMARY A case of vaginal prolapse in a South Australian Sea Lion is described. Conservative treatment proved unsuccessful, and an ovariohysterectomy was performed. Problems concerning anaesthesia, surgery and post-operative management of this marine species are discussed. 相似文献
40.
Giardia isolates from eight horses from New York State (NY), USA and two horses from Western Australia (WA) were genetically characterized at the SSU-rDNA and triose-phosphate isomerase (TPI) genes. Phylogenetic analysis of the TPI gene provided strong support for the placement of both isolates of Giardia from horses in WA and a single isolate from a horse in NY within the assemblage AI genotype of G. duodenalis. Another two isolates from horses in NY placed within the assemblage AII genotype of G. duodenalis. Phylogenetic analysis of the TPI gene also provided strong bootstrap support for the placement of four G. duodenalis isolates from horses in NY into a potentially host-specific sub-assemblage of assemblage BIV. The results of this study are consistent with previous studies showing that assemblages AI and AII of G. duodenalis provide the greatest potential zoonotic risk to humans. Horses may therefore constitute a potential source for human infection of Giardia either directly or via watersheds. 相似文献