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OBJECTIVE: Hematopoietic stem cells are important clinically, both as targets of disease and as reagents for cellular therapy. Studies in hematopoietic stem cell biology have been hampered by difficulties in purifying and manipulating these cells. To facilitate these studies, we sought to develop a system for targeting genes of interest to the hematopoietic stem cell compartment in transgenic mice. MATERIALS AND METHODS: We used Sca-1, a glycosyl phosphatidylinositol-anchored protein expressed on the surface of all hematopoietic stem cells in commonly used inbred mouse strains. We created a mutant Sca-1 allele in which the enhanced green fluorescent protein (EGFP) cDNA is integrated into the Sca-1 locus by homologous recombination in embryonic stem cells. RESULTS: EGFP protein is detectable in all hematopoietic tissues of mice heterozygous for the mutant Sca-1 allele. Growth and development of these mice are normal. No adverse effects of long-term, high-level EGFP expression were noted. Sca-1 positive cells coexpress EGFP in all tissues and lineages examined, as predicted by the targeting strategy. Sca-1 and EGFP expression are coordinately up-regulated in splenocytes from mutant mice. The Lin(-)EGFP(+) bone marrow population contains all progenitor activity in Sca-1(+)(/EGFP) mice. The Lin(-)EGFP(+) bone marrow cells are equivalent to Lin(-)Sca-1(+) cells in long-term repopulation and serial transplantation assays. CONCLUSION: The hematopoietic stem cell compartment appears to be targeted in Sca-1(+)(/EGFP) mutant mice. This system should be useful for studying the normal biology of hematopoietic stem cells and for targeting other genes to this cellular compartment. 相似文献
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Structure of genes for virus-associated RNAI and RNAII of adenovirus type 2. 总被引:31,自引:0,他引:31 下载免费PDF全文
G Akusj?rvi M B Mathews P Andersson B Vennstr?m U Pettersson 《Proceedings of the National Academy of Sciences of the United States of America》1980,77(5):2424-2428
A DNA sequence, 552 base pairs in length, encoding the two "virus-associated" (VA) RNAs of adenovirus type 2 is presented. Comparison of the oligonucleotide maps of VA RNAI and VA RNII with the established sequence permits identification of the genes for these RNAs. VA RNAI is 157-160 nucleotides long and VA RNAII 158-163 nucleotides long, depending on the exact length of their heterogeneous 3' end. The genes are separated by a spacer of about 98 nucleotides. The RNAs exhibit scattered regions of primary sequence homology and can adopt secondary structures which resemble each other closely in their configuration and stability. VA RNAII is also capable of assuming a different configuration that is energetically more favorable. The data suggest that the two RNA genes may have arisen by duplication of an ancestral gene and that the folding of the RNA chain may be of importance for the function of VA RNAs. Hypothetical RNA polymerase III recognition sequences and the coding potential of the region are discussed. 相似文献
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H M Mathews J A Fried I G Kagan 《The American journal of tropical medicine and hygiene》1975,24(3):417-421
Soluble antigens were prepared from Plasmodium falciparum and P. vivax and were evaluated in the indirect hemagglutination test. These antigens, attached to aldehyde-fixed type "O" erythrocytes, detected antibodies in more than 91% of infections with the homologous Plasmodium species. Detection rates in infections caused by the heterologous species ranged from 72% to 76%. Positive reactions occurred in less than 2% of sera from persons without malaria infection. 相似文献
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Hormone profile in lepromatous leprosy. A preliminary study 总被引:2,自引:0,他引:2
R Rolston M Mathews P M Taylor T S Koshy 《International journal of leprosy and other mycobacterial diseases : official organ of the International Leprosy Association》1981,49(1):31-36
In a preliminary study, 11 male patients with lepromatous leprosy were evaluated with regard to endocrinopathy and hormonal status. Basal circulating hormone levels were estimated with a view to correlating the biochemical findings and clinical features. Thyroid hormones T3 and T4, Free Thyroxine Index (FTI), TSH, and cortisol were within normal limits, indicating that further study of these hormones would not be worthwhile. The finding of elevated levels of prolactin as well as the gonadotrophins LH and FSH, however, promises to yield more valuable information if studied in greater detail in a larger group of patients. 相似文献
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Christenson Catherine Martinez-Vazquez Pablo Breidenstein Max Farhang Borzoo Mathews Jackson Melia Umberto Jensen Erik Weber Mathews Donald 《Journal of clinical monitoring and computing》2021,35(6):1421-1428
Journal of Clinical Monitoring and Computing - Comparison of two depth of anesthesia indices, qCON (Conox) and PSI (Sedline), during desflurane sedation and their sensitivity to random ketamine... 相似文献
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