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1.
Volatile components of field- and glass greenhouse-grown tomatoes(Lycopersicon esculentum MILL., variety, V. R. Moscow) of differentmaturities were studied by gas-liquid and thin-layer chromatography.The following components were separated and identified: isobutylalcohol, isopentyl alcohol, hexyl alcohol, 2-methyl-3-hexanol,isovaleraldehyde, caproaldehyde, benzaldehyde, furfural, isopentylacetate, isopentyl butyrate, isopentyl isovalerate, butyl hexanoate,hexyl hexanoate, methyl salicylate and -pinene. Chromatogramswere consistent for both field- and greenhouse-grown tomatoesat all stages of maturity. Except for isovaleraldehyde and hexylalcohol, the biosynthesis of volatile components increased alongwith the growth of fruit. Isovaleraldehyde and hexyl alcohol,presumed to give the "green leafy" aroma of tomatoes, were foundto be in their highest concentrations at the breaker and thelarge-green stages, respectively.
1This research was supported by a research grantUI 00449fromthe National Center for Urban and Industrial Health, U. S. PublicHealth Service. 相似文献
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3.
Evidence for Linkage of Bipolar Disorder to Chromosome 18 with a Parent-of-Origin Effect 总被引:16,自引:8,他引:8 下载免费PDF全文
O. Colin Stine Jianfeng Xu Rebecca Koskela Francis J. McMahon Michele Gschwend Carl Friddle Chris D. Clark Melvin G. McInnis Sylvia G. Simpson Theresa S. Breschel Eva Vishio Kelly Riskin Harriet Feilotter Eugene Chen Susan Shen Susan Folstein Deborah A. Meyers David Botstein Thomas G. Marr J. Raymond DePaulo 《American journal of human genetics》1995,57(6):1384-1394
A susceptibility gene on chromosome 18 and a parent-of-origin effect have been suggested for bipolar affective disorder (BPAD). We have studied 28 nuclear families selected for apparent unilineal transmission of the BPAD phenotype, by using 31 polymorphic markers spanning chromosome 18. Evidence for linkage was tested with affected-sib-pair and LOD score methods under two definitions of the affected phenotype. The affected-sib-pair analyses indicated excess allele sharing for markers on 18p within the region reported previously. The greatest sharing was at D18S37: 64% in bipolar and recurrent unipolar (RUP) sib pairs (P = .0006). In addition, excess sharing of the paternally, but not maternally, transmitted alleles was observed at three markers on 18q: at D18S41, 51 bipolar and RUP sib pairs were concordant for paternally transmitted alleles, and 21 pairs were discordant (P = .0004). The evidence for linkage to loci on both 18p and 18q was strongest in the 11 paternal pedigrees, i.e., those in which the father or one of the father's sibs is affected. In these pedigrees, the greatest allele sharing (81%; P = .00002) and the highest LOD score (3.51; θ = 0.0) were observed at D18S41. Our results provide further support for linkage of BPAD to chromosome 18 and the first molecular evidence for a parent-of-origin effect operating in this disorder. The number of loci involved, and their precise location, require further study. 相似文献
4.
This paper deals with stochasticm-compartmental systems with continuous time-dependent infusions into all compartments and reversible time-independent flows
between any two compartments. A methodology for the first two moments of the distribution of the number of units in the different
compartments at any point in time is outlined without resorting to the usual techniques of generating functions and inverse
Laplace transforms. A possible application to a systems analysis of the kidney transplant system is discussed. 相似文献
5.
报道了7个楼梯草属和赤车属植物(荨麻科)新纪录,它们分别为锐齿楼梯草(E. cyrtandrifolium),变黄楼梯草(E. xanthophyllum),对叶楼梯草(E. sinense),宽叶楼梯草(E. platyphyllum),托叶楼梯草(E. nasutum),短叶赤车(P. brevifolia)和华南赤车(P. grijsii)。列出了各个物种的标本引证和地理分布情况。 相似文献
6.
越南苦苣苔科植物四新记录种 总被引:2,自引:0,他引:2
报道了4个苦苣苔科(Gesneriaceae)植物在越南的分布新记录,其中1种为半蒴苣苔属(Hemiboea)的红苞半蒴苣苔(H.rubribracteata),2种为报春苣苔属(Primulina Hance)的文采报春苣苔(P.wentsaii)和疏花报春苣苔(P.laxi flora),还有1种为吊石苣苔属(Lysionotus)的桂黔吊石苣苔(L.aesch ynanthoides)。文中列出了每个种的标本引证和地理分布情况。 相似文献
7.
Hiscock SJ McInnis SM Tabah DA Henderson CA Brennan AC 《Journal of experimental botany》2003,54(380):169-174
Senecio squalidus (Oxford Ragwort) is being used as a model species to study the genetics and molecular genetics of self-incompatibility (SI) in the Asteraceae. S. squalidus has a strong system of sporophytic SI (SSI) and populations within the UK contain very few S alleles probably due to a population bottleneck experienced on its introduction to the UK. The genetic control of SSI in S. squalidus is complex and may involve a second locus epistatic to S. Progress towards identifying the female determinant of SSI in S. squalidus is reviewed here. Research is focused on plants carrying two defined S alleles, S(1) and S(2). S(2) is dominant to S(1) in pollen and stigma. RT-PCR was used to amplify three SRK-like cDNAs from stigmas of S(1)S(2) heterozygotes, but the expression patterns of these cDNAs suggest that they are unlikely to be directly involved in SI or pollen-stigma interactions in contrast to SSI in the Brassicaceae. Stigma-specific proteins associated with the S(1) allele and the S(2) allele have been identified using isoelectric focusing and these proteins have been designated SSP1 (Stigma S-associated Protein 1) and SSP2. SSP1 and SSP2 cDNAs have been cloned by 3' and 5' RACE and shown to be allelic forms of the same gene, SSP. The expression of SSP and its linkage to the S locus are currently being investigated. Initial results show SSP to be expressed exclusively in stigmas and developmentally regulated, with maximal expression occurring at and just before anthesis when SI is fully functional, SSP expression being undetectable in immature buds. Together these data suggest that SSP is a strong candidate for a Senecio S-gene. 相似文献
8.
Irradiation of puparia in Mediterranean fruit fly, Ceratitis capitata (Wiedemann), sterile insect release programs can negatively affect adult fly performance. Emergence, survivorship, lure attraction, and mating competition tests were performed on irradiated and unirradiated Mediterranean fruit flies in Hawaii. Unirradiated flies of the Vienna-7 (tsl) strain had higher emergence, flight ability, and survivorship compared with irradiated flies. In general, unirradiated flies were more responsive to trimedlure, but this effect was not consistent for all strains at every age. Laboratory strains, of both unirradiated and irradiated flies, responded to trimedlure at a younger age than wild flies, which may be a result of inadvertent selection for decreased development time in laboratory-reared flies. Mating competition tests with irradiated and unirradiated flies showed no significant differences. Costs associated with the irradiation process and the development of alternative control techniques are discussed. 相似文献
9.
The success of the sterile insect technique (SIT) depends critically upon mating between released sterilized males and wild females. In Hawaii, improvements in the efficiency of sterile males were attempted on two separate fronts – mating enhancement and survival improvement. In the former, two methods have been investigated – selective breeding and aromatherapy. In the latter, flies which survived in field cages for several days were selected and bred to produce progeny with enhanced survival ability compared to control flies. Regarding mating selection, standard laboratory-reared males that successfully mated with wild females in field cages were allowed to breed. F1 offspring were inbred, then the selection procedure was repeated for four additional cycles. In the aromatherapy procedure, laboratory-reared males were exposed to ginger root oil for several hours 1 day prior to testing in field cages. Compared to controls, the selected flies improved the mating competitiveness of male flies ca. 3-fold, irradiation reduced this increase to ca. 2.5-fold. Exposing the selected, hybrid strain raised the fitness of the lab males to ca. 9-fold that of wild males. In the ongoing survival selection study, we have obtained lines in which the selected males survived ca. 2-fold better than laboratory control males over several days in an outdoor field cage, with food and water provided. The goal is to combine the traits of higher survival and mating ability into a single strain for SIT release. 相似文献
10.
Brittney McInnis Stevan Marcus 《Biochemical and biophysical research communications》2010,399(4):665-669
In the fission yeast, Schizosaccharomyces pombe, cyclic AMP (cAMP)-dependent protein kinase (PKA) is not essential for viability under normal culturing conditions, making this organism attractive for investigating mechanisms of PKA regulation. Here we show that S. pombe cells carrying a deletion in the adenylate cyclase gene, cyr1, express markedly higher levels of the PKA catalytic subunit, Pka1, than wild type cells. Significantly, in cyr1Δ cells, but not wild type cells, a substantial proportion of Pka1 protein is hyperphosphorylated. Pka1 hyperphosphorylation is strongly induced in cyr1Δ cells, and to varying degrees in wild type cells, by both glucose starvation and stationary phase stresses, which are associated with reduced cAMP-dependent PKA activity, and by KCl stress, the cellular adaptation to which is dependent on PKA activity. Interestingly, hyperphosphorylation of Pka1 was not detected in either cyr1+ or cyr1Δ S. pombe strains carrying a deletion in the PKA regulatory subunit gene, cgs1, under any of the tested conditions. Our results demonstrate the existence of a cAMP-independent mechanism of PKA catalytic subunit phosphorylation, which we propose could serve as a mechanism for inducing or maintaining specific PKA functions under conditions in which its cAMP-dependent activity is downregulated. 相似文献