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排序方式: 共有432条查询结果,搜索用时 515 毫秒
1.
A retrovirus carrying the polyomavirus middle T gene induces acute thrombocythemic myeloproliferative disease in mice. 总被引:2,自引:0,他引:2
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A Fusco G Portella M Grieco G Tajana G Di Minno N Polli A Pinto 《Journal of virology》1988,62(1):361-365
Mice inoculated with an artificially constructed retrovirus carrying the middle T gene of polyomavirus develop acute myeloproliferative disease with severe thrombotic and hemorrhagic disorder and impaired platelet function. The megakaryocytic lineage appears to be a target for polyoma-murine leukemia virus infection and middle T gene expression. This newly described disease represents a unique model system for studying disorders of the megakaryocytic lineage. 相似文献
2.
We have isolated the delta-globin gene of the New-World spider monkey,
Ateles geoffroyi, and compared its nucleotide sequence with those of other
primate delta- and beta-globin genes. Among primate delta-globin genes, the
rate of nonsynonymous substitutions is much less than the rate of
synonymous substitutions. This suggests that primate delta- globin genes
may remain under evolutionary conservation, perhaps because hemoglobin A2
has an as yet unknown physiological importance.
相似文献
3.
P Ruggeri C della Valle R De Fusco L Paladino 《Bollettino della Società italiana di biologia sperimentale》1991,67(10-11):955-960
In this work we determined the hydrocarbon , sterol and triterpenoid composition of two plants used as antibacterial drug in traditional peruvian medicine, Berberis rariflora and Chenopodium multifidum. In both plants the presence of unsaturated hydrocarbons is very low, whereas the presence of odd hydrocarbons is considerable. The delta 7 sterols are more abundant than delta 5 sterols. We found also a great presence of stigmasterol derivatives in both plants, whereas lanosterol derivates are more abundant in B. rariflora. The microbiological tests shows for both plants an evident antibacterial activity against Gram(+) bacteria. 相似文献
4.
A mos oncogene-containing retrovirus, myeloproliferative sarcoma virus, transforms rat thyroid epithelial cells and irreversibly blocks their differentiation pattern. 总被引:8,自引:1,他引:7
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A Fusco G Portella P P Di Fiore M T Berlingieri R Di Lauro A B Schneider G Vecchio 《Journal of virology》1985,56(1):284-292
5.
Biochemical pathways in prokaryotes can be traced backward through evolutionary time 总被引:10,自引:0,他引:10
For the first time, a credible prokaryotic phylogenetic tree is being
assembled by Woese and others using quantitative sequence analysis of
oligonucleotides in the highly conservative rRNA. This provides an
evolutionary scale against which the evolutionary steps that led to the
arrangement and regulation of contemporary biochemical pathways can be
measured. This paper presents an emerging evolutionary picture of aromatic
amino acid biosynthesis within a large superfamily assemblage of
prokaryotes that is sufficiently developed to illustrate a new perspective
that will be applicable to many other biochemical pathways.
相似文献
6.
Nadia Mastroianni Maurizio De Fusco Massimo Zollo Giulia Arrigo Orsetta Zuffardi Alberto Bettinelli Andrea Ballabio Giorgio Casari 《Genomics》1996,35(3):486
Electrolyte homeostasis is maintained by several ion transport systems. Na–(K)–Cl cotransporters promote the electrically silent movement of chloride across the membrane in absorptive and secretory epithelia. Two kidney-specific Na–(K)–Cl cotransporter isoforms are known, so far, according to their sensitivity to specific inhibitors. We have cloned the human cDNA coding for the renal Na–Cl cotransporter selectively inhibited by the thiazide class of diuretic agents. The predicted protein sequence of 1021 amino acids (112 kDa) shows a structure common to the other members of the Na–(K)–Cl cotransporter family: a central region harboring 12 transmembrane domains and the 2 intracellular hydrophilic amino and carboxyl termini. The ex- pression pattern of the human Na–Cl thiazide-sensitive cotransporter (hTSC, HGMW-approved symbol SLC12A3) confirms the kidney specificity. hTSC has been mapped to human chromosome 16q13 by fluorescencein situhybridization. The cloning and characterization of hTSC now render it possible to study the involvement of this cotransport system in the pathogenesis of tubulopathies such as Gitelman syndrome. 相似文献
7.
In Drosophila pseudoobscura, the amylase (Amy) multigene family is
contained within a series of inversions, or gene arrangements, on the third
chromosome. The Standard (ST), Santa Cruz (SC), and Tree Line (TL)
inversions are central to the phylogeny of arrangements, and have clusters
of other arrangements derived from them. The gene arrangements belonging to
each of these three clusters have a characteristic number of Amy genes,
ranging from three in ST to two in SC to one in TL. This distribution
pattern can reflect a history of either duplications or deletions, although
the data available in the past did not permit a decision between these
alternatives. We provide unambiguous evidence that three Amy genes were
present before the divergence of the ST, SC, and TL arrangements. Thus, the
current status of the Amy multigene family is the result of deletions in
the TL and SC arrangements, which created three new pseudogenes: TL
Amy2-psi, TL Amy3-psi, and SC Amy3- psi. Analysis of pseudogene sequences
revealed that, in the SC and ST arrangements, pseudogene evolution has been
retarded, most likely due to the homogenization effect of gene conversion.
Finally, by determining the original copy number, we have reconstructed the
evolutionary history of the Amy multigene family and linked it with the
evolution of the central gene arrangements.
相似文献
8.
The ability of a menhaden oil (MO) diet to influence cercarial penetration into mouse tail skin was evaluated. Male CD-1 mice 4-6 wk old (15.2 g average weight) were fed a 0, 10%, or 20% MO-supplemented diet for 2 wk. After this time mice were infected with either 65 +/- 3 or 145 +/- 3 [35S]methionine/cysteine-labeled cercariae for 1 hr by tail immersion. Twenty-four hours and 7 days later groups of mice were killed and their tail skin removed and autoradiographed. At 24 hr postinfection, mice fed a 20% MO diet had significantly higher cercarial penetration than controls and 10% MO diets (56% +/- 5.2 vs. 44% +/- 2.9, P = 0.02, 1-tailed t-test). After 7 days mice fed a 20% MO diet retained more radioactive foci than controls or 10% MO diets (21% +/- 2.0 vs. 15% +/- 1.3, P = 0.01, 1-tailed t-test). 相似文献
9.
The application of sensory methodology for measuring deodorizing effect of an air conditioner equipped with electric plasma was introduced. Deodorizing effect was measured using chemical and sensory methods at different time (0, 30 and 60 min) and mode (control, blowing and cooling) of an air conditioner. Smoke from a roll of cigarette in a closed room was used as a source of odor and the concentrations of acetic acid and ammonia were measured as odorous chemical components. As one of the sensory methods triangle test was used and as a first step to obtain deodorizing effects by triangle test, the threshold of each panelist was obtained as the log dilution ratio of odor concentration at which the difference from odorless air was detected. The odor concentration at each time and mode was calculated using the threshold of the panel and the deodorizing effect was obtained on the basis of the odor concentration. In addition to a triangle test, scaling methods such as category scaling or magnitude estimation were used to measure deodorizing effect of an air conditioner. Deodorizing effects by scaling methods were calculated based on odor intensity with time at each mode. The regression analysis was done between the efficacy of deodorizing effect by sensory test and those by acetic acid and ammonia, the R2 values of the regression equations for triangle test, category scale, and magnitude estimation were 0.84, 0.72 and 0.69, respectively. Deodorizing effect by triangle test explained the decrease of acetic acid and ammonia better than those by category scaling or magnitude estimation while high cost and time consuming labor involved in triangle tests reduced the merit. The results of this study demonstrated that various sensory methods could be used to measure deodorizing effect of air conditioners and further researches on fast and reliable methods are needed to establish the official procedures. 相似文献
10.