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Robert Rosen 《Bulletin of mathematical biology》1960,22(2):199-205
An error appearing in the proof of Theorem 4 of a previous paper of the author’s (1959,Bull. Math. Biophysics,21, 289–97) is pointed out, and a new proof of the theorem is supplied. We also obtain a corollary from Theorem 3 ofloc. cit. which reveals the existence of a hitherto unrecognized class of codes. 相似文献
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Kern, Jerome (Pacific Research Section, Honolulu, Hawaii), and Leon Rosen. Identification of enteroviruses by hemagglutination-inhibition. J. Bacteriol. 91:1936-1942. 1966.-Approximately 40% of a group of 906 enterovirus isolates cytopathic for monkey cell cultures were found to possess hemagglutinins for human erythrocytes when tested at temperatures of 4 and 37 C and at pH 5.8 and 7.3. The hemagglutinating isolates could be classified by relatively simple techniques into 18 serotypes. Four of these serotypes, echovirus type 24 and coxsackievirus B types 1, 5, and 6, had not previously been known to include hemagglutinating strains. One serotype, Toluca-3, represented a previously unrecognized enterovirus, and two other serotypes may also represent previously unrecognized enteroviruses. 相似文献
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A 2 year survey of ixodid ticks in the Judean area of Israel between 1983 and 1985 showed that sheep were parasitized by the following species:Rhipicephalus sanguineus group (30.6%),Rhipicephalus bursa (25.3%),Haemaphysalis cretica (20.5%),Haemaphysalis otophila (20.1%) andHyalomma anatolicum excavatum (3.1%). Three other species,Hyalomma marginatum rufipes, Boophilus annulatus andAmblyomma lepidum were also present but in very low numbers. A total of 50 816 specimens (78.1% adult ticks) were collected from the sheep. In the field, a total of 4780 ticks (8.7% adults) were collected and 64.3% consisted ofR. bursa. Other species found wereH. cretica (14.5%),H. a. excavatum (13.7%),H. otophila (3.4%),R. sanguineus group (1.9%) and 1.7% wasIxodes eldaricus. The number of ticks collected varied from year to year and seasonal activity was observed in all species except forH. a. excavatum. In all species, males outnumbered females, with the exception ofH. cretica. The seasonal occurrence, tick ecology and disease relationship is discussed for each species. 相似文献
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Lipopolysaccharide induction of tissue factor gene expression in monocytic cells is mediated by binding of c-Rel/p65 heterodimers to a kappa B-like site. 总被引:10,自引:2,他引:8 下载免费PDF全文
P A Oeth G C Parry C Kunsch P Nantermet C A Rosen N Mackman 《Molecular and cellular biology》1994,14(6):3772-3781
Exposure of monocytic cells to bacterial lipopolysaccharide (LPS) activates the NF-kappa B/Rel family of proteins and leads to the rapid induction of inflammatory gene products, including tissue factor (TF). TF is the primary cellular initiator of the coagulation protease cascades. Here we report the characterization of a nuclear complex from human monocytic cells that bound to a kappa B-like site, 5'-CGGAGTTTCC-3', in the 5'-flanking region of the human TF gene. This nuclear complex was activated by LPS with kinetics that preceded induction of the TF gene. In vitro binding studies demonstrated that the TF site bound translated c-Rel and p65 homodimers but not p50/p65 heterodimers or p50 homodimers. Base-pair substitutions in the TF site indicated that the presence of a cytosine at position 1 precluded binding of NF-kappa B. In fact, under low-ionic-strength conditions, the TF complex did not migrate with translated p50/p65 dimers but instead comigrated with c-Rel/p65 dimers. Antibodies against the NF-kappa B and Rel proteins and UV cross-linking studies revealed the presence of c-Rel and p65 and the absence of p50 in the TF complex and further showed that c-Rel/p65 heterodimers selectively bound to the TF kappa B-like site. Functional studies indicated that the TF site conferred LPS inducibility on a heterologous promoter and was transactivated by c-Rel or p65. Taken together, our results demonstrated that binding of c-Rel/p65 heterodimers to a novel kappa B-like site mediated LPS induction of TF gene expression in monocytic cells. 相似文献