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531.
As part of the diagnostic workup following an episode of fetal loss, it is generally recommended that fetal tissue be submitted for chromosome analysis and that the fetus be photographed and radiographed. Our recent clinical experience has suggested that, in those fetuses where size is compatible, xeroradiography may be superior to standard radiography. Xeroradiography utilizes principles similar to those in film radiology, with low-energy photon beams and relatively long exposure times. The physical characteristics of the beam and imaging system provide optimal soft tissue visualization. We have found this technique to be of use in studying a broad variety of abortuses with abnormalities. Examples of fetal abnormalities in which we have used this technique include acardia, neural tube defects, nuchal cystic hygroma, and arthrogryposis. In fetuses weighing 500-1,000 gm, the exposure settings are 25 MA, 1 second, 40 KVP. For larger fetuses the KVP should be increased by 1 or 2. This technique has not been useful for a complete body view of large fetuses due to the size limitations of the xeroradiographic cassette itself. 相似文献
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Plant-nematode populations associated with uncultivated vegetation, adjacent strawberry plants, and alternate crop sites were studied at three locations in Minnesota. At one site (Forest Lake), Paratylenchus projectus, Meloidogyne hapla, and Pratylenchus tenuis were frequently associated with the roots of native vegetation. These nematode species were also present in adjacent strawberry beds. Among alternate crops observed, oats and muskmelon usually supported the fewest nematodes although moderate densities of Xiphinema americanum and P. tenuis were found at one location in plots planted to oats. Pratylenchus tenuis was also found on rye at one location. 相似文献
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J. F. Crow 《Genetics》1996,144(3):855-859
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A high striatum: cerebellum ratio of 77Br-p-bromospiperone (77Br-BrSp) was observed in rat brain following tail vein injection of the drug. Striatal 77Br-BrSp was stereospecifically displaced by the isomers of flupenthixol. After chronic haloperidol administration striatal dopamine receptor supersensitivity was demonstrated both by increased 3H-spiperone binding to striatal membranes in vitro and by increased striatal 77Br-BrSp content. These results confirm and extend previous findings and enhance interest in the use of 77Br-BrSp for the in vivo assessment of central dopamine receptors in man. 相似文献