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271.
W. V. Murray P. Lalan A. Gill M. F. Addo J. M. Lewis D. K. H. Lee R. Rampulla M. P. Wachter J. D. Hsi D. C. Underwood 《Bioorganic & medicinal chemistry letters》1992,2(12):1775-1779
A novel series of substituted piperidine-2-ones has been identified as antagonists of angiotensin II. These compounds showed high affinity for the receptor in bovine adrenal cortex binding assays with IC50's as low as 20nM. They are potent inhibitors of angiotensin II induced contractions in rabbit aortic rings, with pA2 values as high as 9. A number of these compounds are also orally active as antihypertensives in spontaneously hypertensive rat preparations. 相似文献
272.
S. S. Bhagwat C. Boswell C. Gude N. Contardo D. S. Cohen J. Mathis R. Dotson W. Lee S. Shetty 《Bioorganic & medicinal chemistry letters》1992,2(12):1619-1622
(3-Pyridinyl)alkanoic acids substituted at the 4-position with an (arylsulfonamido)alkyl group were synthesized and found to behave as platelet thromboxane receptor antagonists (TxRAs) and thromboxane synthase inhibitors (TxSIs). The compounds behaved as agonists at the vascular receptor for thromboxane A2. 相似文献
273.
The molecular mechanism of microtubule bundling has been enveloped in controversy for the past few years. At the centre of the debate are MAPs: are they necessary for the formation of microtubule bundles? In this article, Gloria Lee and Roland Brandt weigh the evidence and propose that microtubule stability might be the crucial factor in microtubule bundling. Perhaps then MAPs might act as spacer molecules between microtubules. 相似文献
274.
Characterization of a pyridine-degrading branched Gram-positive bacterium isolated from the anoxic zone of an oil shale column 总被引:1,自引:0,他引:1
Sung-Taik Lee Seung-Bong Lee Yong-Ha Park 《Applied microbiology and biotechnology》1991,35(6):824-829
Summary From the anoxic zone of an oil shale leachate column three pyridine-degrading bacterial strains were isolated. Two strains were Gram-negative facultative anaerobic rods and one strain was a branched Gram-positive bacterium. The branched Gram-positive strain had the best pyridine-degrading ability. This organism was aerobic, non-motile, catalase positive, oxidase negative, and had no flagellum. The G+C content of the DNA was 66.5 mol%. The major menaquinone was MK-8(H2). The main cellular fatty acids were saturated and monounsaturated straight chains. This organism contained mycolic acid, meso-diaminopimelic acid, arabinogalactan and glycolyl residues in the cell wall. Due to morphological, physiological and chemotaxonomic characteristics this strain was placed in the genus Rhodococcus. The optimum culture conditions were as follows: temperature 32° C, pH 8.0 and 0.1% v/v of pyridine as sole carbon, energy and nitrogen source. Utilization of pyridine by a batch fermentor culture of Rhodococcus sp. was characterized by a specific growth rate of 0.13 h–1, growth yield of 0.61 mg cell·mg pyridine–1 and a doubling time of 5.3 h–1.
Offprint requests to: S.-T. Lee 相似文献
275.
H. Nquyen H.H. Le R.Y. Lee M. Staufenbiel J.M. Palacios G. Mengod H. Lübbert 《Neurochemistry international》1991,19(4):433-436
We have previously isolated serotonin 5-HT1C receptor cDNA clones. In contrast to most other receptors coupled to GTP binding proteins, the 5-HT1C receptor gene contains several introns in its coding region. A similar exon-intron distribution is found in the 5-HT2 receptor gene. The presence of large introns tempted us to test whether exchange of exons contributes to serotonin receptor heterogeneity. Therefore, blots with RNAs from different regions of the brain and brain slices were hybridized in situ with probes representing individual exons. We did not find any evidence for the exchange of exons which should result in an unequal distribution of hybridization signals found with the exon-specific probes. With the methodology used we should be able to see differential splicing in the form where individual exons are used alternatively resulting in mRNAs coding for different serotonin receptor types. We would not, however, see if a given exon can be modified by the alternative use of several splice-junctions. 相似文献
276.
277.
278.
Overexpression of transforming growth factor-beta in transgenic mice carrying the human T-cell lymphotropic virus type I tax gene. 总被引:4,自引:0,他引:4 下载免费PDF全文
S J Kim T S Winokur H D Lee D Danielpour K Y Kim A G Geiser L S Chen M B Sporn A B Roberts G Jay 《Molecular and cellular biology》1991,11(10):5222-5228
Human T-cell lymphotropic virus type I (HTLV-I) has been associated with an adult form of T-cell leukemia as well as tropical spastic paraparesis, a neurodegenerative disease. Adult T-cell leukemia patients express high levels of the type 1 isoform of transforming growth factor-beta (TGF-beta 1), which is mediated by the effects of the HTLV-I Tax transactivator protein on the TGF-beta 1 promoter. To understand further the regulation of TGF-beta 1 expression by Tax, we examined its expression in transgenic mice carrying the HTLV-I tax gene. We show that tumors from these mice and other tissues, such as submaxillary glands and skeletal muscle, which express high levels of tax mRNA selectively express high levels of TGF-beta 1 mRNA and protein. Moreover, TGF-beta 1 significantly stimulated the incorporation of tritiated thymidine into one of three cell lines derived from neurofibromas of tax-transgenic mice, which suggests that the excessive production of TGF-beta 1 may play a role in tumorigenesis and that these mice may serve as a useful model for studying the biological effects of TGF-beta in vivo. 相似文献
279.
Transactivation of the grp78 promoter by malfolded proteins, glycosylation block, and calcium ionophore is mediated through a proximal region containing a CCAAT motif which interacts with CTF/NF-I. 总被引:8,自引:1,他引:7 下载免费PDF全文
S K Wooden L J Li D Navarro I Qadri L Pereira A S Lee 《Molecular and cellular biology》1991,11(11):5612-5623