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1.
Tumor necrosis factor induces acute phase proteins in rats 总被引:2,自引:0,他引:2
I Gresser F Delers N Tran Quangs S Marion R Engler C Maury C Soria J Soria W Fiers J Tavernier 《Journal of biological regulators and homeostatic agents》1987,1(4):173-176
Inoculation of WAG rats with recombinant mouse tumor necrosis factor results in a rapid and marked increase in several acute phase proteins in the serum (haptoglobin, alpha 1 acid glycoprotein, alpha 2 macroglobulin) and in the plasma (fibrinogen). We conclude that TNF may play an important role in the inflammatory response in vivo and possibly in the pathogenesis of inflammatory disorders. 相似文献
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Arsenio Fernández-López Carlos Soria Victoria Revilla Tomás Gómez Pedro Calvo 《Neurochemical research》1994,19(4):445-449
At 4 days after the implantation of two subcutaneous 75 mg morphine pellets in the back skin, rats were morphine-dependent. In the three layers studied in the occipital cortex we found that the values of the 2-adrenergic agonist [3H]bromoxidine binding increased with respect to animals implanted with placebo pellets. Typical behavioral and physiological symptoms of the abstinence syndrome appeared 30 minutes after administration of naloxone, [3H]bromoxidine binding values being similar to those obtained in animals implanted with placebo pellets. The pattern of response of the [3H]bromoxidine binding was similar in the hippocampus and the superficial gray layer of the superior colliculus of the mesencephalon, but the differences were not statistically significant in these areas. This paper concludes that exist brain regional differences in the 2-adrenoreceptors response under morphine-treatment and possibly under naloxone-induced morphine abstinence syndrome. 相似文献
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The phylogeny of Greya Busck (Lepidoptera: Prodoxidae) was inferred from
nucleotide sequence variation across a 765-bp region in the cytochrome
oxidase I and II genes of the mitochondrial genome. Most parsimonious
relationships of 25 haplotypes from 16 Greya species and two outgroup
genera (Tetragma and Prodoxus) showed substantial congruence with the
species relationships indicated by morphological variation. Differences
between mitochondrial and morphological trees were found primarily in the
positions of two species, G. variabilis and G. pectinifera, and in the
branching order of the three major species groups in the genus. Conflicts
between the data sets were examined by comparing levels of homoplasy in
characters supporting alternative hypotheses. The phylogeny of Greya
species suggests that host-plant association at the family level and larval
feeding mode are conservative characters. Transition/transversion ratios
estimated by reconstruction of nucleotide substitutions on the phylogeny
had a range of 2.0-9.3, when different subsets of the phylogeny were used.
The decline of this ratio with the increase in maximum sequence divergence
among taxa indicates that transitions are masked by transversions along
deeper internodes or long branches of the phylogeny. Among transitions,
substitutions of A-->G and T-->C outnumbered their reciprocal
substitutions by 2-6 times, presumably because of the approximately 4:1
(77%) A+T-bias in nucleotide base composition. Of all transversions,
73%-80% were A<-->T substitutions, 85% of which occurred at third
positions of codons; these estimates did not decrease with an increase in
maximum sequence divergence of taxa included in the analysis. The high
frequency of A<-->T substitutions is either a reflection or an
explanation of the 92% A+T bias at third codon positions.
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The life-history parameters reproduction rate, developmental time and age specific survival of the western flower thrips,Frankliniella occidentalis (Pergande) [Thysanoptera: Thripidae], were determined on susceptible and resistant cucumber (Cucumis sativus L.) genotypes. Both newly emerged andF. occidentalis females of mixed ages showed a substantial reduction (36 to 50%) of the reproduction rate on all resistant genotypes, in
particular after the second day. On the resistant genotypes 9127 and 9140,F. occidentalis had a prolonged developmental period. This was primarily due to a prolongation of the second larval stage. On all resistant
genotypes,F. occidentalis suffered from high (82 to 97%) preadult mortality, predominantly at the second larval stage. It is conclude that the resistant
genotypes do not cause an immediate intoxication of adult nor preadult thrips stages. 相似文献
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