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21.
AG Loeser Z Shen DS Dessau DS Marshall CH Park P Fournier A Kapitulnik 《Science (New York, N.Y.)》1996,273(5273):325-329
Angle-resolved photoemission experiments reveal evidence of an energy gap in the normal state excitation spectrum of the cuprate superconductor Bi2Sr2CaCu2O8+delta. This gap exists only in underdoped samples and closes around the doping level at which the superconducting transition temperature Tc is a maximum. The momentum dependence and magnitude of the gap closely resemble those of the dx2-y2 gap observed in the superconducting state. This observation is consistent with results from several other experimental techniques, which also indicate the presence of a gap in the normal state. Some possible theoretical explanations for this effect are reviewed. 相似文献
22.
Serum chloramphenicol concentrations in preruminant calves: a comparison of two formulations dosed orally 总被引:1,自引:0,他引:1
E. M. HUFFMAN C. H. CLARK J. D. OLSON L. BALL 《Journal of veterinary pharmacology and therapeutics》1981,4(3):225-231
Serum concentrations of chloramphenicol were determined after oral doses (55 mg/kg body weight) were administered to 7–9 day old Holstein-Friesian calves. Chloramphenicol in an oral solution produced greater serum concentrations than did an equivalent dose of chloramphenicol in capsules ( P <0.005). A second dose of each formulation administered 12 h after the first dose elevated serum chloramphenicol concentrations significantly ( P <0.001). The average serum chloramphenicol concentration exceeded 5 μg/ml of serum 1 h after administration of the solution compared with 4 h for the capsules. Average serum chloramphenicol concentration was greater than 5 μg/ml for at least 12 h after the dose was administered for both formulations. Of the eight calves receiving repeat doses of chloramphenicol, seven (87.5%) developed diarrhea in 76 ± 8.6 h. Six of the eight calves (75%) died during or shortly after the period of chloramphenicol administration. 相似文献
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M.R.M. CLARK 《EPPO Bulletin》1981,11(3):317-322
Artificial field inoculation showed that in one year out of two, Fusarium roseum caused significant yield loss in barley grown from organomercury-treated seed. No significant yield loss occurred in either year as a result of inoculation with Fusarium nivale. Results from field, pot and blotter tests suggested that inoculation with F. nivale and sometimes F. roseum could at times be associated with increased vigour in barley. There was a fairly consistent trend particularly with F. nivale for this to occur to a greater extent in plants from untreated seed than in those from treated seed. Similarly, any reductions in vigour associated with inoculation with more pathogenic strains of either species occurred only, or to a greater extent, in plants from treated seed. There was some evidence of an increased capacity for regenerative root and shoot growth in barley plants damaged by Fusarium inoculation, and it is suggested that increased growth may be associated with increases in percentage dry weights of the shoot 8 but not 18 days after inoculation. In the absence of inoculation, the effect of seed treatment was to increase grain yields, though this was not clearly associated with the increases it sometimes caused in emergence and in 1000-grain weight. 相似文献
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The effects of 3 ovine and one bovine strains of Bacteroides nodosus on the severity of foot-rot, bodyweight and wool growth were compared in Merino sheep in a field experiment. Based on the severity of the induced foot lesions, one strain was classed as virulent (causing underrunning lesions in most feet), one was benign (causing lesions of the interdigital skin only), and 2, including the bovine strain, were of intermediate virulence (causing underrunning lesions in a small proportion of feet). Differences among strains in their effect on foot-rot severity and bodyweight were significant when compared over the whole experimental period, but were not significant at any single time of measurement, because of large differences between replicates. Bodyweight loss and severity of foot-rot caused by the virulent strain were significantly greater than that caused by the benign strain. The intermediate strains lay between these 2 extremes in terms of both bodyweight and foot-rot scores but were not significantly different from either in a statistical sense. Total greasy wool weight did not differ among groups over the whole experiment, but the rate of wool growth during the period when foot lesions were most prevalent and severe was reduced appreciably by the virulent strain and to a lesser extent by the intermediate strains. 相似文献
26.
K. SAOULIDIS S. C. KYRIAKIS S. KENNEDY S. LEKKAS CH. C. MILIOTIS G. ALLAN G. C. BALKAMOS P. A. PAPOUTSIS 《Zoonoses and public health》2002,49(4):202-205
Post‐weaning multisystemic wasting syndrome (PMWS) and porcine dermatitis and nephropathy syndrome (PDNS) are two recently described conditions of pigs at the late nursery and fattening stages. The aim of this short communication was to describe the first reported occurrence of these conditions and of porcine circovirus type 2 (PCV2) infection in Greece. The clinical signs, gross post‐mortem changes and histopathological changes observed in affected pigs, were similar to those previously described for both PDNS and PMWS. As in previous reports, the lesions were associated with PCV2 infection, which was demonstrated by immunohistochemical and in situ hybridization methods. 相似文献
27.
GARY J. SPODNICK DVM Diplomate ACVS MICHAEL M. PAVLETIC DVM Diplomate ACVS GEOFFREY N. CLARK DVM Diplomate ACVS SCOTT H. SCHELLING DVM Diplomate ACVP KARL H. KRAUS dvm ms Diplomate acvs 《Veterinary surgery : VS》1993,22(6):436-443
Controlled tissue expansion using a 100 cc rectangular silicone elastomer expander was performed in the mid-antebrachium and mid-crus of eight adult mixed-breed dogs. Two expander inflation schedules were followed. Group 1 dogs (n = 4) underwent expander inflation using 10 cc sterile saline every other day, and group 2 dogs (n = 4) underwent expander inflation using 15 cc sterile saline every other day until the nominal volume (100 cc) was attained. Significant mean postexpansion increases in skin surface area of 94.1 cm2 (35.9%) and 108.9 cm2 (37.3%) were measured in the antebrachium and crus, respectively (p < .05). In a second procedure, the expanders were removed and skin flaps were developed from the redundant tissue generated during the expansion process. Single pedicle advancement flaps and transposition flaps were used to cover surgically created defects measuring 5 times 10 cm in the antebrachium and cms. Single pedicle advancement flaps consistently measured 10 × 10 cm and could be advanced to cover defects involving one third of the mid-antebrachial or mid-crural circumference. Transposition flaps were rotated up to 170 and the donor site defects were easily closed under minimal or no tension. Complications included an abscess in one dog and seroma formation in four dogs. Differences in success or complication rates between group 1 dogs and group 2 dogs were not observed; an accelerated inflation schedule using 15 cc sterile saline every other day was recommended. 相似文献
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