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51.
52.
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
53.
54.
Hybertson Brooks M.; Bursten Stuart L.; Leff Jonathan A.; Lee Young M.; Jepson Eric K.; Dewitt Chris R.; Zagorski John; Cho Hyun G.; Repine John E. 《Journal of applied physiology》1997,82(1):226-232
Hybertson, Brooks M., Stuart L. Bursten, Jonathan A. Leff,Young M. Lee, Eric K. Jepson, Chris R. Dewitt, John Zagorski, Hyun G. Cho, and John E. Repine. Lisofylline prevents leak, but not neutrophil accumulation, in lungs of rats given IL-1intratracheally. J. Appl. Physiol.82(1): 226-232, 1997.Interleukin-1 (IL-1) is increased in lunglavages from patients with the acute respiratory distress syndrome, andadministering IL-1 intratracheally causes neutrophil accumulation and aneutrophil-dependent oxidative leak in lungs of rats. In the presentstudy, we found that rats pretreated intraperitoneally with lisofylline[(R)-1-(5-hydroxyhexyl)-3,7-dimethylxanthine (LSF)], an inhibitor of lysophosphatidic acid acyl transferase, which reduces the production of unsaturated phosphatidic acid species,did not develop the lung leak or the related ultrastructural abnormalities that occur after intratracheal administration of IL-1.However, rats pretreated with LSF and then given IL-1 intratracheally did develop the same elevations of lung lavage cytokine-induced neutrophil chemoattractant (CINC) levels and the same increased numbersof lung lavage neutrophils as rats given IL-1 intratracheally. Lungs ofrats given IL-1 intratracheally also had increased unsaturated phosphatidic acid and free acyl (linoleate, linolenate) concentrations compared with untreated rats, and these lipid responses were prevented by pretreatment with LSF. Our results reveal that LSF decreases lungleak and lung lipid alterations without decreasing neutrophil accumulation or lung lavage CINC increases in rats given IL-1 intratracheally. 相似文献
55.
Jane C. Schneider Hugly Suzanne Chris R. Somerville 《Plant Molecular Biology Reporter》1995,13(1):11-17
Twenty-one mutants ofArabidopsis thaliana were isolated that developed chlorosis or necrosis upon incubation at low temperature (10°C to 15°C). Crosses among mutants
in different phenotypic classes showed that mutants in three of four classes were found in a small number of loci.
This article is reproduced fromWeeds World, vol. 1. For electronic access toWeeds World, see PMBR 12(4):302–303. 相似文献
56.
Accuracy of predicting protein secondary structure and solvent accessibility from sequence information has been improved significantly by using information contained in multiple sequence alignments as input to a neural 'network system. For the Asilomar meeting, predictions for 13 proteins were generated automatically using the publicly available prediction method PHD. The results confirm the estimate of 72% three-state prediction accuracy. The fairly accurate predictions of secondary structure segments made the tool useful as a starting point for modeling of higher dimensional aspects of protein structure. © 1995 Wiley-Liss, Inc. 相似文献
57.
Carrie Haskell-Luevano Lakmal W. Boteju Victor J. Hruby 《Letters in Peptide Science》1995,1(4):163-170
Summary Nitrogen indole protection of the -methyltryptophan side-chain residue is important for avoiding undesired side reactions during peptide synthesis. Of great importance is the choice of a side-chain protecting group for orthogonal peptide synthesis and its stability under a variety of chemical conditions required for synthesis of the four isomers of this unusual amino acid. We report here the successful use of the mesitylenesulfonyl (Mts) protecting group for -methyltryptophan in the synthesis of melanotropin and CCK peptide analogues and the ready cleavage of this protecting group under HF conditions. 相似文献
58.
Defective regulation of the cytosolic Ca2+ activity in parathyroid cells from patients with hyperparathyroidism 总被引:2,自引:0,他引:2
Rolf Larsson Chris Wallfelt Håkan Abrahamsson Erik Gylfe Sverker Ljunghall Jonas Rastad Patrik Rorsman Leif Wide Göran Åkerström 《Bioscience reports》1984,4(11):909-915
The parathyroid hormone (PTH) release and cytosolic Ca2+ activity were determined in normal bovine parathyroid cells and parathyroid cells obtained from patients with hyperparathyroidism (HPT). There was a sigmoid relation between the cytosolic Ca2+ activity and the extracellular calcium concentration between 0.5 and 6.0 mmol/l. The PTH release was inhibited in parallel with the rise in the cytosolic Ca2+ activity. Both the hormone release and the cytosolic Ca2+ activity were lower in cells from human adenomas and hyperplastic glands~ and in comparison with the bovine preparations these ceils had higher set points for the cytosolic Ca2+ activity and PTH release. There was a close correlation between the individual set points for the cytosolic Ca2+ activity and PTH release in a material containing both normal and pathological cells. The results indicate that the abnormal PTH release characteristic of HPT is due to a defective regulation of the cytosolic Ca2+ activity. 相似文献
59.
60.
Peter van der Meijden Chris van der Drift Godfried D. Vogels 《Archives of microbiology》1984,138(4):360-364
The conversion of methanol by cell-free extracts of the acetogenic bacterium Eubacterium limosum was studied. Incubation of mixed cell-free extracts of both E. limosum and Methanobacterium formicicum resulted in methane formation from methanol in the presence of ATP and 2-mercaptoethanesulfonic acid. The separate extracts were not able to perform this reaction. Addition of ferredoxin obtained from Methanosarcina barkeri to the mixed extracts resulted in increased methane formation. The enzyme, responsible for methanol binding in cell-free extract of E. limosum, was inactivated by FAD under N2 and exhibited maximal activity under an atmosphere of H2. This enzyme contains a firmly bound cobalamin which was methylated by methanol in the presence of ATP. It was demethylated in the presence of methylcobalamin: coenzyme M methyltransferase obtained from M. barkeri under concomitant formation of methylated coenzyme M. These properties are similar to those of methanol: 5-hydroxybenzimidazolylcobamide methyltransferase from M. barkeri. It was proposed that methylotrophic acetogens and methylotrophic methanogens use similar enzymes in the first step of methanol conversion.Abbreviations HS-CoM
2-mercaptoethanesulfonic acid
- CH3S-CoM
2-(methylthio)ethanesulfonic acid
- BrES
2-bromoethanesulfonic acid
- TES
N-tris(hydroxymethyl)-methyl-2-aminoethanesulfonic acid
- MT1
methanol: 5-hydroxybenzimidazolylcobamide methyltransferase
- MT2
methylcobalamin
- HS-CoM
methyltransferase
- DMBI
5,6-dimethylbenzimidazole and HBI, 5-hydroxybenzimidazole, are -ligands of corrinoids
- (S-CoM)2
2,2-dithiodiethanesulfonic acid 相似文献