Library

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 11
    Electronic Resource
    Electronic Resource
    Amsterdam : Elsevier
    Phytochemistry 16 (1977), S. 315-317 
    ISSN: 0031-9422
    Keywords: Gramineae ; Zea mays L. ; amino acid composition ; isoelectric focusing. ; maize ; protein bodies ; zein
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Biology , Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 12
    Electronic Resource
    Electronic Resource
    Springer
    Sexual plant reproduction 1 (1988), S. 202-207 
    ISSN: 1432-2145
    Keywords: Asparagus ; DNA complexity ; DNA content ; Male and female mRNAs
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary As a first approach in investigating the genetical bases of sexual dimorphism in the dioecious plant Asparagus offcinalis L. at the molecular level, we have determined DNA content per cell, DNA sequence complexity and mRNA activities in both developing and mature male and female flowers of Asparagus. 2C DNA content (around 3.9 pg) was independent of sex and rather low when compared to other Liliiflorae; sequence complexity, however, showed a high proportion of repeated sequences. Polyadenylated mRNA from male and female flowers at young and mature stages of development were assayed by in vitro translation in the presence of [35S]methionine, and the synthesized proteins were analysed by two-dimensional gel electrophoresis. Results have shown that there are no appreciable differences in polypeptide patterns from male and female flowers at a young stage of development, while specific sequences of mRNA are produced only very late during the development, most likely linked to the appearance of mature pollen grains and mature megagametophy tes.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 13
    Electronic Resource
    Electronic Resource
    Springer
    Sexual plant reproduction 3 (1990), S. 236-243 
    ISSN: 1432-2145
    Keywords: Asparagus ; Growth regulators ; Peroxidases ; Sex differentiation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Using an immunological method we assayed the levels of auxin, abscisic acid and three cytokinins (transzeatin riboside, dihydrozeatin riboside, isopentenyladenosine) in flowers of female and male plants of Asparagus officinalis L. at different stages of development. The largest differences between the sexes were found for auxin: auxin content was found to be about three times higher in young male flowers than in female flowers at a corresponding developmental stage. In order to identify some of the biochemical markers linked to sex differentiation, we also examined peroxidase isoenzyme patterns during flower development. We found five flower-specific peroxidase bands, three of which appear to be localized in the anthers. In young flowers still sexually undifferentiated in their morphology these bands are present in both sexes. They subsequently rapidly disappear in the female flower (approximately at the same time as when anther development is blocked), while they persist for a much longer time in the male. The temporary presence of these peroxidase isoenzymes in female young flowers together with the large difference in auxin content indicate that the stage of the young flower is a crucial moment in the process of sex determination.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 14
    Electronic Resource
    Electronic Resource
    Amsterdam : Elsevier
    BBA Section Nucleic Acids And Protein Synthesis 324 (1973), S. 254-266 
    ISSN: 0005-2787
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Biology
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 15
    Electronic Resource
    Electronic Resource
    Amsterdam : Elsevier
    BBA Section Nucleic Acids And Protein Synthesis 324 (1973), S. 72-77 
    ISSN: 0005-2787
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Biology
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 16
    Electronic Resource
    Electronic Resource
    Springer
    International archives of occupational and environmental health 67 (1995), S. 41-46 
    ISSN: 1432-1246
    Keywords: N,N-Dimethylformamide ; Urine ; DMF-mercapturic acid ; N-methylformamide ; Formamide
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Some methods for analysing N,N-dimethylformamide and its metabolites [hydroxymethyl-N-methylformamide, hydroxymethylformamide and N-acetyl-S-(N-methylcarbamoyl)cysteine] in the urine of exposed workers are described. Unchanged dimethylformamide was measured after pretreatment of urine (2 ml) with silica gel cartridges and elution with methanol. The gas chromatographic analysis using a nitrogen phosphor detector made it possible to detect N,N-dimethylformamide in urine even when workers were exposed to low concentrations of the solvent (about 1 mg/m3). N-Hydroxymethyl-N-methylformamide and N-hydroxymethylformamide were analysed as N-methylformamide and formamide respectively after direct injection of urine into the gas chromatograph. The injection port temperature played an important role in the gas chromatographic determination of these products. Reliable results were obtained when direct or split injections were performed at 250°C. The splitless injection gave the same reliable results at 150°C. In urine samples from occupationally non-exposed persons, N-methylformamide could not be detected. In contrast, formamide (or its precursor, hydroxymethylformamide) was present in every urine sample. Our results in respect of 19 urine samples analysed with the injection port of the gas chromatograph at 250°C gave a mean of 8.6 mg/l of formamide. N-Acetyl-S-(N-methylcar-bamoyl)cysteine was determined using a modified method for analysing organic acid in urine samples. The metabolite was extracted with ethyl ether in an acid environment, treated with a silylating reagent and measured by gas chromatography/mass spectrometry.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 17
    Electronic Resource
    Electronic Resource
    Springer
    International archives of occupational and environmental health 68 (1996), S. 22-26 
    ISSN: 1432-1246
    Keywords: Nitrous oxide ; Blood ; Urine ; Environment ; Theatre personnel ; General population
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Nitrous oxide (N2O) was assayed in 676 urine samples and 101 blood samples provided after exposure by operating theatre personnel from nine hospitals. The blood and urine assays were repeated in 25 subjects 18 h after the end of exposure. For 80 subjects, environmental N2O was also measured during intraoperative exposure. Mean urinary N2O in the 676 subjects at the end of exposure was 40 μg/l (range 1–3805 μg/l); in 10 of the 676 subjects, urinary N2O was in the range 279–3805 μg/l (mean 1202 μ/l). The 98th percentile was 120 μg/l. Mean blood N2O at the end of exposure, measured in 101 subjects, was 21 μg/l (median 16 μg/l, range 1–75 μg/l). Blood and urine N2O (1.5 μg/l and 4.9 μg/l, respectively) in 25 subjects, 18 h after exposure, was significantly higher than in occupationally non-exposed subjects (blood 0.91 μg/l, urine 1 μg/l). Environmental exposure was significantly related to blood and urinary N2O (r = 0.59 andr = 0.64, respectively). Blood and urinary N2O were significantly related to each other (r = 0.71), and were equivalent to about 25% of the environmental exposure level. The mean urinary N2O of 1202 μg/l in 10/676 subjects was not related to environmental exposure in the operating theatre. The highest urinary N2O levels measured in these 10/676 subjects could be explained by an asymptomatic urinary infection.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 18
    ISSN: 1432-1246
    Keywords: Styrene ; Biological monitoring ; Blood ; Alveolar air ; Normal population
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Blood styrene was measured by a gas chromatography-mass spectrometry method in 81 “normal people” and in 76 workers exposed to styrene. In the normal subjects, styrene was also tested in alveolar and environmental air. Styrene was found in nearly all (95%) blood samples. Average styrene levels in the normal subjects were 221 ng/1 in blood (Cb), 3 ng/1 in alveolar air (Ca) and 6 ng/1 in environmental air (Ci). Styrene levels did not differ significantly between smokers and non-smokers, 95% of values being below 512 ng/1 in Cb, 7 ng/1 in Ca and 15 ng/l in Ci. In workers with an average exposure to styrene of 204 μg/l, at the end of the workshift, mean blood styrene concentration was 1211 μg/l. In blood samples collected at the end of the Thursday shift, styrene levels were significantly higher (1590 μg/1) than those found at the end of the Monday shift (1068 μg/l. A similar difference was found in samples taken the morning after exposure (60 and 119 μg/l, respectively). Significant correlations between blood and environmental styrene were found both at the end of the shift and the morning after exposure (r=0.61 and 0.41, respectively). In workers occupationally exposed to styrene, 16 h after the end of the workshift, blood styrene (94 μg/l) was significantly higher than that found in the normal subjects (0.22 μg/l). The half-life of blood styrene was 3.9 h.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 19
    Electronic Resource
    Electronic Resource
    Springer
    Theoretical and applied genetics 52 (1978), S. 263-267 
    ISSN: 1432-2242
    Keywords: Zein synthesis ; Gene regulation ; Opaque-2 ; linkage relationships
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The synthesis of at least 15 zein polypeptides is under the control of regulatory gene loci. One of these, Opaque-2 (chromosome 7, position 16) strongly reduces the zein accumulation without modifying the zein molecular components. The linkage relationship between the regulatory gene 02 and the 5 structural loci (Zp1, Zp2, Zp3, Zp6, Zp12) segregating with sample Mendelian ratios have been studied. Zp1, Zp2, Zp3 are closely linked to each other; moreover this gene cluster is located on chromosome 7 at 5.5 cM from the Opaque-2 locus. The structural loci Zp6 and Zp12 are not linked with each other, with the 02 locus or with Zp1, Zp2, Zp3. From our data it follows that the zein structural genes are located in at least three positions on the maize genome. The scattering in the genome of the genes controlled by the Opaque-2 locus suggests a transacting role for this regulatory element.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 20
    ISSN: 1432-2242
    Keywords: Maize endosperm ; Zein ; High-lysine genes ; Storage proteins
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary This paper describes a new dominant mutation of maize, Mc, which interferes in the endosperm with the synthesis of storage proteins. The mutant is characterized by an opaque phenotype; it reduces the deposition of zein and it increases the level of methionine. The mutation is specifically related to storage protein synthesis since soluble and insoluble carbohydrates are present at normal levels. The main interest of this mutant lies in its synergistic interaction with opaque-2 in repressing zein synthesis. In the double mutant o2Mc the accumulation of zein is reduced to less than 10% of that of the normal endosperm. The control on zein synthesis exerted by the double mutant is at the level of production or stability of translatable zein mRNAs. The double mutant o2Mc germinates well offering the opportunity of using it in biochemical and molecular studies related to storage protein synthesis; the reduced endosperm weight of o2Mc negates its practical utilization in breeding maize for quality.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...