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1.
Daily subcutaneous BST injection in lactating cows, bulls and castrated male dwarf goats did not induce significant changes in the pharmacokinetic parameters of antipyrine (AP) and sulphadimidine (SDD). Similarly, no changes were obtained after injection of slow-release BST formulations in lactating cows and non-lactating female goats. In contrast to androgenic hormones, both zeranol and proligestone had no effect upon the disposition of AP and SDD, although both synthetic hormones did induce enhanced plasma somatotropin concentrations. In goats, metabolic effects induced by zeranol and BST included significant reductions in plasma urea values, whereas plasma creatinine levels were somewhat lower after daily BST administration.  相似文献   
2.
Efficacy of moxidectin injection (ProHeart 6 Sustained Release Injectable for Dogs, Fort Dodge Animal Health) against naturally acquired infections of Trichuris vulpis was compared with that of milbemycin oxime/lufenuron tablets (Sentinel Flavor Tabs, Novartis Animal Health). Eighteen dogs infected with T. vulpis were ranked by egg counts and randomly allocated to treatment with moxidectin (170 micro g/kg), milbemycin (500 micro g/kg)/lufenuron (10 mg/kg), or to an untreated control group (six dogs per treatment). Dogs were euthanized for worm counting 7 days after treatment. Efficacy of milbemycin/lufenuron against T. vulpis was 99.6 %, compared with 67.5 % for moxidectin. The commercial formulation of milbemycin oxime/lufenuron provided excellent control of whipworm infection, whereas moxidectin demonstrated variable efficacy against this parasite.  相似文献   
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Long base line interferometry: a new technique   总被引:1,自引:0,他引:1  
The technique of using magnetic-tape recorders and atomic frequency standards to operate two widely separated radio telescopes as a phase-coherent interferometer when the stations have no radio-frequency connecting link has been successfully tested at the National Research Council of Canada's Algonquin Radio Observatory.  相似文献   
5.
"Dark beams" are nonuniform optical beams that contain either a one-dimensional (1D) dark stripe or a two-dimensional (2D) dark hole resulting from a phase singularity or an amplitude depression in their optical field. Thus far, self-trapped dark beams (dark solitons) have been observed using coherent light only. Here, self-trapped dark incoherent light beams (self-trapped dark incoherent wavepackets) were observed. Both dark stripes and dark holes nested in a broad partially spatially incoherent wavefront were self-trapped to form dark solitons in a host photorefractive medium. These self-trapped 1D and 2D dark beams induced refractive-index changes akin to planar and circular dielectric waveguides. The experiments introduce the possibility of controlling high-power coherent laser beams with low-power incoherent light sources such as light emitting diodes.  相似文献   
6.
A coppicing technique was used to assess the incidence of latent and missed infection around 76 outbreaks of cocoa swollen shoot disease found during routine surveys of cocoa farms in Ghana. When all apparently healthy trees were coppiced within at least 27 m of trees found with symptoms, some failed to regenerate, with overall mortalities of 15% and 19% in progenies of Upper Amazon and West African Amelonado parentage, respectively. Many of the regenerating shoots developed stem and/or leaf symptoms of swollen shoot disease within 3 years of coppicing. There were great differences between sites, with overall incidences of infection of 21% and 16% in the Amazon and Amelonado plantings, respectively. The infections revealed by coppicing were not usually grouped closely around trees originally found with symptoms. Gradients of infection were seldom evident and the overall incidence of infection within 3 m of the initial outbreak areas (17%) was little greater than that beyond (14%). The original inspections of the standing trees detected only c. 12% and 18% of all the infected trees present at the Amazon and Amelonado sites, respectively. These results emphasize the limitations of routine inspections in determining the true incidence of infection. They have an important bearing on the conduct and effectiveness of the eradication measures adopted in Ghana and are discussed in relation to the future policy for limiting spread.  相似文献   
7.
Congenital porto-systemic shunts in sixteen dogs and three cats   总被引:1,自引:0,他引:1  
Congenital porto-systemic shunts in sixteen dogs and three cats are described. A major symptom was hepato-encephalopathy. In most cases diagnosis was based on elevated venous ammonia levels, abnormal ammonia tolerance and results of operative mesenteric portography. Clinical signs, laboratory findings, results of portography, and pathologic findings in the liver and the central nervous system are described. A diagnostic schedule is proposed to aid in recognition of this syndrome.  相似文献   
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Aritua  Legg  Smit  & Gibson 《Plant pathology》1999,48(5):655-661
A study compared the spread of sweet potato virus disease (SPVD) into crops of two moderately resistant and initially SPVD-free sweet potato cultivars in northern and southern Mpigi, Uganda. Whiteflies, the vector of sweet potato chlorotic stunt crini virus (SPCSV), a component cause of SPVD, were similarly abundant in farmers' sweet potato fields around Namulonge in northern Mpigi, and Kanoni in southern Mpigi. However, mean incidence of SPVD in farmers' crops neighbouring the trials was higher at Kanoni (13.3%) than at Namulonge (2.8%). Furthermore, spread of SPVD into initially SPVD-free sweet potato plots of two only moderately resistant cultivars was greater in plots at Kanoni than in plots at Namulonge. The SPVD-resistant New Kawogo was the most common cultivar grown in farmers' fields at Namulonge and had few diseased plants, whereas susceptible cultivars with relatively high incidences of disease predominated at Kanoni. Final SPVD incidence in each trial was positively correlated with a measure combining the proximity and level of inoculum in surrounding fields. The study demonstrates the importance of local SPVD inoculum in determining the rate of spread of the disease into fields and implies that the widespread cultivation of a resistant variety limits infection of susceptible cultivars grown nearby.  相似文献   
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