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41.
Staining patterns suggest that in the adeno-associated satellite virion there exist quasi single-stranded regions which are renatured after extraction to exhibit double strandedness. 相似文献
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Immunohistochemical absence of adrenergic neurons in the dorsal part of the solitary tract nucleus in sudden infant death 总被引:1,自引:0,他引:1
F Chigr M Najimi D Jordan L Denoroy J Pearson M Tommasi R Gilly N Kopp 《Comptes rendus de l'Académie des sciences. Série III, Sciences de la vie》1989,309(12):543-549
The immunohistochemical distribution of TH and PNMT containing neuronal elements was investigated utilizing peroxidase anti-peroxidase methods in newborn control and sudden infant death syndrome (SIDS) brainstems. The TH immunoreactive neurons, within the medulla oblongata, displayed a similar distribution in both control and SIDS tissue. However, PNMT immunoreactive neurons seen in the dorsal part of the nucleus of tractus solitarius in control tissue were not observed in SIDS tissue. This alteration of adrenergic neurons in the dorsal part of NTS (region reported to be implicated in the control of blood pressure and respiration) could explain the cardiorespiratory disorders in SIDS. 相似文献
49.
Large-scale mapping and chromosome jumping in the q27 region of the human X chromosome 总被引:2,自引:0,他引:2
We have used pulsed field gel electrophoresis for further physical mapping studies in the q27 region of the human X chromosome. We show that the DXS 102 locus and the F9 gene are separated by only 300 kb despite a genetic distance of 1.4 cM; this linkage orients our large-scale map and shows that the mcf.2 transforming sequence is telomeric to F9. A BssHII complete-digest jumping library was used to jump toward the DXS 105 locus; a 130-kb jump was achieved and the corresponding "linking clone" was obtained. 相似文献
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Construction and characterization of two infectious molecular clones of encephalomyocarditis virus. 总被引:5,自引:4,他引:1 下载免费PDF全文
We constructed and characterized two infectious molecular clones of encephalomyocarditis (EMC) virus. Both constructs, pDL and pDA, were assembled from five overlapping cDNA clones derived from the diabetogenic variant of EMC virus (EMC-D) and from two synthetic oligonucleotide cartridges. pDA contained a single point mutation at position 1720 within the "puff" region of capsid protein 1AB that was derived from the nondiabetogenic variant of EMC virus (EMC-B). This point mutation resulted in an amino acid substitution of arginine (EMC-B) for lysine (EMC-D). Our construction illustrates two novel findings: (i) that the problem of stably cloning long poly(C) tracts of EMC virus can be circumvented by the use of a shortened, synthetic, poly(dC-dG) oligonucleotide cartridge, and (ii) that a single point mutation in the puff region of the capsid protein 1AB leads to change in its electrophoretic mobility and to a change in the plaque size of recombinant virus. 相似文献