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1.
Three third trimester fetuses were exposed to a subgroup 2, type 7 adenovirus (adeno 7) by intraamnionic infection. The virus caused preterm delivery of two clinically ill calves and one stillbirth. The two premature calves died 12 and 72 hours after birth. An elevated serum neutralizing antibody titer (1:256) to adenovirus 7 was found in one principal calf at birth. Adenovirus 7 was recovered from several tissues of the live calves and the spleen of the stillborn calf. Fetuses exposed by intraamniotnic injection with virus carrier only, were born healthy after normal gestational periods and no viruses were isolated from the tissues. Clinically ill calves were weak, severely depressed and unable to stand and nurse. Gross postmortem lesions were nonspecific and consisted of petechial and ecchymotic hemorrhages and edema of the gastrointestinal tract. Histopathological lesions included vasculitis, necrosis of the mucosa of the forestomach, mild gastroenteritis and acute, nonsuppurative focal necrosis of the liver, kidney and adrenal gland. Intranuclear inclusion bodies were seen in pericytes, macrophages, hepatocytes, epithelial cells of adrenal cortical sinusoids of the zona glomerulosa and zona fasciculata and renal tubular epithelium. 相似文献
2.
A survey of the aerobic bacteria in the feces of captive raptors 总被引:5,自引:0,他引:5
Feces of 47 captive raptors belonging to the order Falconiformes or Strigiformes were cultured for bacteria. Gram-negative bacteria, which were cultured from the feces of 45 of the 47 raptors, were the most common isolates. A wide variety of species were identified, including a newly described genus (Moellerella wisconsensis), two newly described species (Escherichia fergusonii and Proteus penneri), and a member of a newly described enteric group (CDC Enteric group 41). Additional organisms identified that have not been reported in previous bacteriological surveys of raptors were Salmonella heidelberg, Salmonella braenderup, Morganella morganii, Yersinia ruckeri, Serratia spp., and Kluyvera sp. Escherichia coli, isolated from the feces of 42 of the 47 raptors, was the most frequently recovered. Streptococcus faecalis, the second most common isolate, was cultured from 30 birds. Several differences were observed between fecal bacteria isolated from raptors fed commercially prepared chicken and those isolated from raptors not fed chicken. The most obvious difference was that birds fed chicken had more varied gram-negative bacterial species and in greater numbers per fecal sample. The potential for the isolated bacteria from raptors as pathogens in humans and avian species is discussed. 相似文献
3.
E Stauber M Papageorges R Sande L Ward 《Journal of the American Veterinary Medical Association》1990,196(6):939-940
A 10-year-old female cockatiel in a thin and depressed condition and with a 1 X 2-cm soft abdominal swelling was hospitalized. Radiography revealed a well-circumscribed mass containing punctate areas of mineralization, displacing the gizzard cranially in the caudodorsal portion of the abdomen. There was bilateral, symmetric, generalized, increased medullary opacity of the radius, ulna, carpometacarpus, femur, tibiotarsus, and tarsometatarsus. These findings were compatible with polyostotic hyperostosis secondary to an estrogen-secreting tumor. Euthanasia and necropsy were requested. A small area of neoplastic cells in the oviduct was identified histologically, but most of the tissue mass consisted of necrotic cellular debris. There was no metastasis. Sagittal secretions of decalcified radiopaque bones revealed up to 60% filling of medullary cavities with bone spicules. Although clinical and radiographic findings were compatible with an estrogen-secreting tumor, osteopetrosis, metastatic neoplasia, hypertrophic osteopathy, and metabolic bone disease were included in the initial differential diagnosis. The absence of metastasis and the confinement of the tumor within the oviduct would have made surgical removal a possible approach to treatment. 相似文献
4.
Changes in the macro-pore structure of restored soil caused by compaction beneath heavy agricultural machinery: a morphometric study 总被引:2,自引:0,他引:2
B. Schäffer M. Stauber R. Müller & R. Schulin 《European Journal of Soil Science》2007,58(5):1062-1073
Compaction can seriously degrade soil in modern agriculture. Soil that has been temporarily removed and stored is particularly sensitive to compaction when restored, although little is known about the structural changes in such soils under mechanical loads. We investigated the structural changes in a restored soil that had been gently cultivated for several years and then was trafficked by a heavy combine harvester, analysing the macro‐pore structure by quantitative morphometry of three‐dimensional microcomputed tomography images. Increased trafficking caused decreases in both the porosity and connectivity of the macro‐pores. The fraction of spherical pores (and thus the convexity of the pore space) and the mean pore separation were increased. Trafficking had no clear effect on the orientation of pores. While the mean pore diameter tended to decrease, biopores were more stable than interaggregate pores originating from the packing of soil aggregates. This is relevant for the development of structural stability in restored soils, as the macro‐pores consist mainly of interaggregate pores initially, whereas biopores develop and increase in proportion only gradually over time. Quantitative morphometry provides valuable morphological indices for the objective assessment of the macro‐pore structure and changes induced by compaction. 相似文献
5.
Eperythrozoon coccoides: influence on course of infection of Plasmodium chabaudi in mouse 总被引:2,自引:0,他引:2
Mice infected with Plasmodium chabaudi obtained from two sources were found to be contaminated with Eperythrozoon coccoides. At each transfer of blood parasitized with plasmodia, eperythrozoa were also passed. In the presence of these organisms, the malarial infection assumed a low-level, chronic course infrequently resulting in death of the mice. When the eperythrozoa were eliminated through treatment with oxophenarsine hydrochloride, the malarial infection took an acute course always ending in death. 相似文献
6.
C M Shropshire E Stauber M Arai 《Journal of the American Veterinary Medical Association》1992,200(7):936-939
Pairs of budgerigars were given samples, by gavage, of plants considered potentially toxic to pet birds. Samples were prepared by flash-freezing and powdering fresh plant material in liquid nitrogen and resuspending the material in deionized water for administration. Of the 19 plants tested, only 6 induced clinical signs of illness; these plants included yew, oleander, clematis, avocado, black locust, and Virginia creeper (Taxus media, Nerium oleander, Clematis sp, Persea americana, Robinia pseudoacacia, Parthenocissus quinquefolio). 相似文献
7.
Fine structure constant defines visual transparency of graphene 总被引:1,自引:0,他引:1
Nair RR Blake P Grigorenko AN Novoselov KS Booth TJ Stauber T Peres NM Geim AK 《Science (New York, N.Y.)》2008,320(5881):1308
There are few phenomena in condensed matter physics that are defined only by the fundamental constants and do not depend on material parameters. Examples are the resistivity quantum, h/e2 (h is Planck's constant and e the electron charge), that appears in a variety of transport experiments and the magnetic flux quantum, h/e, playing an important role in the physics of superconductivity. By and large, sophisticated facilities and special measurement conditions are required to observe any of these phenomena. We show that the opacity of suspended graphene is defined solely by the fine structure constant, a = e2/hc feminine 1/137 (where c is the speed of light), the parameter that describes coupling between light and relativistic electrons and that is traditionally associated with quantum electrodynamics rather than materials science. Despite being only one atom thick, graphene is found to absorb a significant (pa = 2.3%) fraction of incident white light, a consequence of graphene's unique electronic structure. 相似文献
8.
A M Hargis E Stauber S Casteel D Eitner 《Journal of the American Veterinary Medical Association》1989,194(1):64-66
Avocados of 2 varieties were mashed and administered via feeding cannula to 8 canaries and 8 budgerigars. Two control budgerigars were given water via feeding cannula. Six budgerigars and 1 canary died within 24 to 47 hours after the first administration of avocado. Deaths were associated with administration of both varieties of avocado. Higher dose was associated with greater mortality. The 2 budgerigars given water were normal throughout the observation period. Results indicated that avocados are highly toxic to budgerigars and less toxic to canaries. Postmortem findings observed in some birds included subcutaneous edema in the pectoral area and hydropericardium. 相似文献
9.
A surgical procedure that ensures intraamnionic inoculation of the bovine fetus is described. Right flank surgical operation was performed, using a "grid"-type entry though the abdominal muscles. A portion of the uterus containing 1 fetal leg was presented for inoculating the test material between the hooves. The procedure was rapid and simple to do and was safe for both the dam and the fetus. 相似文献
10.