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The myc family of proto-oncogenes consists of several members that possess regions of sequence homology and some have known similarities in structure and function. We have isolated an 8.8-kb EcoRI fragment from a human genomic library by hybridization to a 28-base oligonucleotide probe derived from a region of the second exon of MYC, which is highly conserved in the myc gene family. Sequence analysis of this myc-like (MYCLK1) DNA fragment has revealed the existence of a region with 85% homology to the 28-base oligonucleotide probe. An open reading frame of 207 nucleotides containing the region of homology was found. We have mapped MYCLK1 to human chromosome 7 at band p15 by chromosome in situ hybridization; this site is distinct from the map location of previously characterized myc genes. Whether MYCLK1 represents a new functional member of the myc family of proto-oncogenes remains to be determined. 相似文献
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Injection of norepinephrine (NE) into the paraventricular nucleus of the hypothalamus has been shown to elicit eating in satiated rats. In the present study, the monoamine oxidase inhibitor tranylcypromine (TCP), which is known to release endogenous NE, was found to produce a similar effect in rats maintained and tested on a palatable milk-mash combination diet. The effect of this antidepressant drug was positively correlated in magnitude with the NE effect in the same animals. It was selectively antagonized by central injection of drugs which block α-adrenergic receptors. Local pretreatment with NE synthesis inhibitors similarly blocked the TCP eating response but had no effect on eating elicited by exogenous NE. It is suggested from these results that TCP is stimulating eating through the release of endogenous NE from adrenergic neurons innervating the region of the paraventricular nucleus. 相似文献
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Successful infection of the common marmoset (Callithrix jacchus) with human varicella-zoster virus. 总被引:1,自引:0,他引:1 下载免费PDF全文
P J Provost P M Keller F S Banker B J Keech H J Klein R S Lowe D H Morton A H Phelps W J McAleer R W Ellis 《Journal of virology》1987,61(10):2951-2955
The common marmoset, Callithrix jacchus, can be infected with human varicella-zoster virus (VZV), both wild-type strain KMcC and attenuated vaccine strain Oka/Merck. Infection was accomplished with either whole-cell-associated or cell extract VZV by combined oral-nasal-conjunctival application and was characterized by substantial and persistent anti-VZV antibody responses. The infectivity of VZV for marmosets was destroyed by treatment of inocula with heat or UV light. Diluted inocula with as few as 40 PFU/ml were infectious for marmosets. The lungs were demonstrated to be a major site of viral replication; both the presence of viral antigens and signs of pneumonia were demonstrated in lung tissues. Four serial passages of VZV KMcC were carried out in C. jacchus by a process of in vitro isolation and culturing of VZV from infected lung tissue and reapplication of the cultured isolates to fresh animals. The isolated viruses were identified as VZV both serologically and by restriction endonuclease analyses. The C. jacchus infectivity model should prove useful for determining the efficacy of subunit and live recombinant VZV vaccines as well as for the study of zoster. 相似文献