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排序方式: 共有203条查询结果,搜索用时 15 毫秒
1.
Severe mortality in broiler chickens associated with Mycoplasma synoviae and Pasteurella gallinarum.
Severe economic loss due to high mortality and condemnation rates occurred on two commercial broiler facilities. Chickens had moderate-to-severe airsacculitis, pericarditis, perihepatitis, tracheitis, and synovitis. Pasteurella gallinarum was isolated from 16 of 18 pericardia, four of 14 livers, 11 of 16 air sacs, six of seven joints and one of 28 tracheas in pure culture. In addition, Mycoplasma synoviae was isolated from trachea and air sac. Lesions were suggestive of an Escherichia coli septicemia, but E. coli was isolated from only four of 28 tracheas and one of 14 livers in pure culture. A coronavirus was isolated from trachea and lung. Whether this coronavirus represented a vaccine or field strain of infectious bronchitis was not determined. These findings suggested that the severe lesions were due to a concomitant infection with an atypical strain of P. gallinarum. 相似文献
2.
Shapiro JL Julian RJ Hampson RJ Trenton RG Yo IH 《The Canadian veterinary journal. La revue veterinaire canadienne》1988,29(8):636-639
A diagnosis of toxic necrotizing cholangiohepatitis was made in approximately 35% of a flock of 23,000 commercial broiler chickens. Affected chickens were small, and had discrete green foci throughout the liver. Seven to twelve days prior to shipping the flock to slaughter, premixes containing oxytetracycline, monensin, and 3-nitro-4-hydroxyphenylarsonic acid had been added to the ration because the birds had wet droppings and were growing slowly. The 3-nitro-4-hydroxyphenylarsonic acid had been inadvertently incorporated at ten times the recommended level. Liver and kidney of affected birds had elevated levels of total arsenic, and special strains demonstrated arsenic in necrotic foci in liver. Histologically there was marked dilation of intrahepatic bile ducts, and patchy necrosis and hyperplasia of the bile duct epithelium. Damage to bile ducts may have been a toxic manifestation of altered metabolism and excretion of the three drugs being fed to birds suffering from intercurrent diarrhea and/or undefined interactions among the drugs. 相似文献
3.
Shapiro JL Rostkowski C Little PB Smith-Maxie L Julian RJ Van Dreumel AA 《The Canadian veterinary journal. La revue veterinaire canadienne》1985,26(5):155-158
Caprine β-mannosidosis, a fatal inherited deficiency of the lysosomal enzyme β-mannosidase, was diagnosed in neonatal female Nubian crossbred twin kids from a small herd near Guelph, Ontario. The kids had been tetraplegic since birth, with whole body tremors, abnormal nystagmus and an intention tremor of the head. 相似文献
4.
5.
Blue-green algae: why they become dominant 总被引:26,自引:0,他引:26
J Shapiro 《Science (New York, N.Y.)》1973,179(71):382-384
The injection of carbon dioxide and the addition of nitrogen and phosphorus to a lake population dominated by blue-green algae results in a rapid shift to dominance by green algae. The basis for the change and its implications are discussed. 相似文献
6.
7.
Shapiro HL 《Science (New York, N.Y.)》1944,99(2576):373-376
8.
H. Bair‐Brake T. Bell A. Higgins N. Bailey M. Duda S. Shapiro H. E. Eves N. Marano G. Galland 《Zoonoses and public health》2014,61(2):97-104
Bushmeat, defined as meat derived from wild animals, is a potential source of zoonotic pathogens. Bushmeat from restricted animals is illegal to import into the United States under US federal regulations. We reviewed US Centers for Disease Control and Prevention (CDC) port of entry surveillance records from September 2005 through December 2010 and conducted focus group studies to describe trends in and reasons for bushmeat importation into the United States. In total, 543 confiscated bushmeat items were recorded. Half of the confiscated bushmeat items identified were rodents. Africa was the most frequent continent of origin. Seasonality was evident, with bushmeat confiscations peaking in late spring to early summer. Four times more bushmeat was confiscated during an enhanced surveillance period in June 2010 compared with the same period in previous years, suggesting that routine surveillance underestimated the amount of bushmeat detected at US Ports of Entry. Focus groups held in three major US cities revealed that bushmeat importation is a multifaceted issue. Longstanding cultural practices of hunting and eating bushmeat make it difficult for consumers to acknowledge potential health and ecologic risks. Also, US merchants selling African goods, including bushmeat, in their stores have caused confusion among importers as to whether importation is truly illegal. Enhancing routine surveillance for bushmeat and consistent enforcement of penalties at all ports of entry, along with health education aimed at bushmeat importers, might be useful to deter illegal importation. 相似文献
9.
Rensing SA Lang D Zimmer AD Terry A Salamov A Shapiro H Nishiyama T Perroud PF Lindquist EA Kamisugi Y Tanahashi T Sakakibara K Fujita T Oishi K Shin-I T Kuroki Y Toyoda A Suzuki Y Hashimoto S Yamaguchi K Sugano S Kohara Y Fujiyama A Anterola A Aoki S Ashton N Barbazuk WB Barker E Bennetzen JL Blankenship R Cho SH Dutcher SK Estelle M Fawcett JA Gundlach H Hanada K Heyl A Hicks KA Hughes J Lohr M Mayer K Melkozernov A Murata T Nelson DR Pils B Prigge M Reiss B Renner T Rombauts S Rushton PJ 《Science (New York, N.Y.)》2008,319(5859):64-69
We report the draft genome sequence of the model moss Physcomitrella patens and compare its features with those of flowering plants, from which it is separated by more than 400 million years, and unicellular aquatic algae. This comparison reveals genomic changes concomitant with the evolutionary movement to land, including a general increase in gene family complexity; loss of genes associated with aquatic environments (e.g., flagellar arms); acquisition of genes for tolerating terrestrial stresses (e.g., variation in temperature and water availability); and the development of the auxin and abscisic acid signaling pathways for coordinating multicellular growth and dehydration response. The Physcomitrella genome provides a resource for phylogenetic inferences about gene function and for experimental analysis of plant processes through this plant's unique facility for reverse genetics. 相似文献
10.
Rogers AE Cappallo RJ Hinteregger HF Levine JI Nesman EF Webber JC Whitney AR Clark TA Ma C Ryan J Corey BE Counselman CC Herring TA Shapiro II Knight CA Shaffer DB Vandenberg NR Lacasse R Mauzy R Rayhrer B Schupler BR Pigg JC 《Science (New York, N.Y.)》1983,219(4580):51-54
The Mark III very-long-baseline interferometry (VLBI) system allows recording and later processing of up to 112 megabits per second from each radio telescope of an interferometer array. For astrometric and geodetic measurements, signals from two radio-frequency bands (2.2 to 2.3 and 8.2 to 8.6 gigahertz) are sampled and recorded simultaneously at all antenna sites. From these dual-band recordings the relative group delays of signals arriving at each pair of sites can be corrected for the contributions due to the ionosphere. For many radio sources for which the signals are sufficiently intense, these group delays can be determined with uncertainties under 50 picoseconds. Relative positions of widely separated antennas and celestial coordinates of radio sources have been determined from such measurements with 1 standard deviation uncertainties of about 5 centimeters and 3 milliseconds of arc, respectively. Sample results are given for the lengths of baselines between three antennas in the United States and three in Europe as well as for the arc lengths between the positions of six extragalactic radio sources. There is no significant evidence of change in any of these quantities. For mapping the brightness distribution of such compact radio sources, signals of a given polarization, or of pairs of orthogonal polarizations, can be recorded in up to 28 contiguous bands each nearly 2 megahertz wide. The ability to record large bandwidths and to link together many large radio telescopes allows detection and study of compact sources with flux densities under 1 millijansky. 相似文献