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  • Spektralphotometrie  (167)
  • Drosophila melanogaster  (67)
  • Springer  (234)
  • American Institute of Physics (AIP)
  • American Meteorological Society (AMS)
  • Nature Publishing Group
  • 1975-1979  (234)
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  • Springer  (234)
  • American Institute of Physics (AIP)
  • American Meteorological Society (AMS)
  • Nature Publishing Group
  • Wiley-Blackwell  (4)
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  • 1
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    Development genes and evolution 187 (1979), S. 151-165 
    ISSN: 1432-041X
    Keywords: Oogenesis ; Embryogenesis ; Two-dimensional gels ; Protein synthesis ; Drosophila melanogaster
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Protein synthesis in egg follicles and blastoderm embryos ofDrosophila melanogaster has been studied by means of two-dimensional gel electrophoresis. Up to 400 polypeptide spots have been resolved on autoradiographs. Stage 10 follicles (for stages see King, 1970) were labelled in vitro for 10 to 60 min with35S-methionine and cut with tungsten needles into an anterior fragment containing the nurse cells and a posterior fragment containing the oocyte and follicle cells. The nurse cells were found to synthesize a complex pattern of proteins. At least two proteins were detected only in nurse cells but not in the oocyte even after a one hour labelling period. Nurse cells isolated from stages 9, 10 and 12 follicles were shown to synthesize stage specific patterns of proteins. Several proteins are synthesized in posterior fragments of stage 10 follicles but not in anterior fragments. These proteins are only found in follicle cells. No oocyte specific proteins have been detected. Striking differences between the protein patterns of anterior and posterior fragments persist until the nurse cells degenerate. In mature stage 14 follicles, labelled in vivo, no significant differences in the protein patterns of isolated anterior and posterior fragments could be detected; this may be due to technical limitations. At the blastoderm stage localized synthesis of specific proteins becomes detectable again. When blastoderm embryos, labelled in vivo, are cut with tungsten needles and the cells are isolated from anterior and posterior halves, differences become apparent. The pole cells located at the posterior pole are highly active in protein synthesis and contribute several specific proteins which are found exclusively in the posterior region of the embryo. In this study synthesis of specific proteins could only be demonstrated at those developmental stages which are characterized by the presence of different cell types within the egg chamber, while no differences were detected when stage 14 follicles were cut and anterior and posterior fragments analyzed separately. The differences in the pattern of protein synthesis by pole cells and blastoderm cells indicate that even the earliest stages of determination are reflected by marked changes at the biochemical level.
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  • 2
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    Development genes and evolution 187 (1979), S. 167-177 
    ISSN: 1432-041X
    Keywords: Pyrimidine biosynthesis ; rudimentary mutants ; Drosophila melanogaster
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The X-linkedrudimentary (r) mutants ofDrosophila melanogaster are pyrimidine auxotrophs and require exogenous pyrimidines (Nørby, 1970; Falk, 1976). We have established a set ofrudimentary cell lines that are derived from embryos, homozygous for eitherr 1 orr 36. The enzymatic activities of the pyrimidine synthesizing enzymes were measured in the mutant lines. We have further investigated the nutritional requirements of the mutant cells in vitro by using a pyrimidine free culture medium. Ther 1 cell lines were found to express 3–7%dihydroorotase (DHOase) activity as compared to a wildtype cell line. Reducedaspartate transcarbamylase (ATCase) activity was measured in somer 1 cell lines whereas wildtypecarbamylphosphate synthetase (CPSase) activity is expressed in allr 1 cell lines. Ther 36 cell line expresses wildtype activity ofDHOase andCPSase. ATCase activity was found to be reduced to 10% of the wildtype activity. The mutant cell lines do not proliferate in pyrimidine free minimal medium and cell proliferation is obtained by the addition of crude RNA. Proliferation of ther 1 cells is restored by the supplementation of the minimal medium withdihydroorotate whereas proliferation of ther 36 cells is restored by supplementation with eitherdihydroorotate orcarbamylaspartate. The results demonstrate that therudimentary phenotypesr 1 andr 36 are expressed at the cellular level and that the two mutant cell types behave as cellular pyrimidine auxotrophs in vitro.
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  • 3
    ISSN: 1573-4927
    Keywords: sepiapterin synthase ; variegation ; purple ; Drosophila melanogaster ; pteridine eye pigments ; drosopterin
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract A variegated position effect on the autonomous gene, purple, has been studied enzymologically in Drosophila melanogaster. Sepiapterin synthase, the enzyme system associated with pr +, was examined for activity in different developmental stages of the fly. The results indicate that T(Y:2) pr c5, cn/prc4 cn flies (flies in which pr + has been translocated and which exhibit variegation) have a reduced amount of enzyme activity as compared with both Oregon-R and pr 1 flies. This reduction in activity was not found in larval stages, which suggests that the inactivation process probably occurs in late larval or early pupal stages. The phenotype of the variegated adult has white eyes with red-colored spots and patches where drosopterins occur. The phenotype of the fly carrying the translocation is modified by the presence of additional Y chromosomes. This extends the observation from other systems that extra heterochromatin acts to suppress the variegated position effect. The advantages of studying the variegation by measuring enzyme activity, as well as the phenotypic expression, are several; for example, the developmental time at which variegation occurs may be estimated even though drosopterin synthesis is not occurring.
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  • 4
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    Biochemical genetics 17 (1979), S. 1131-1144 
    ISSN: 1573-4927
    Keywords: Drosophila melanogaster ; enzyme polymorphism ; G6PD ; 6PGD ; enzyme activity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract The electrophoretic variants of G6PD and 6PGD isolated from the Bogota Drosophila melanogaster population were characterized developmentally and biochemically. Changes in in vitro enzyme activity during development were comparable to those found for other dehydrogenases: an increase in the larval and adult stage and a decrease in the pupal stage. During the whole life cycle the “S” enzyme of both loci showed a higher activity than the “F” enzyme. MgCl2 had a stimulating effect on the activity of both enzymes whereas their heat stability was decreased. The allozymes of 6PGD had different Vmax's but were comparable with respect to Km values, pH optimum, and stability at 45 C. the allozymes of G6PD showed different Vmax's and differed in stability at 35 C, but had similar Km values and pH optima. As the difference in stability was probably due to differences in molecular structure of the allozymes, the differences in activity found at high pH and high MgCl2 concentration were most probably due to this difference in stability.
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  • 5
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    Biochemical genetics 17 (1979), S. 1-22 
    ISSN: 1573-4927
    Keywords: Drosophila melanogaster ; esterase 6 ; allozymes ; biochemical properties
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Biochemical properties of esterase 6 in Drosophila melanogaster were investigated using partially purified preparations from three genotypes, 1/1, 1/2, and 2/2. The molecular weight of the enzyme is estimated to be about 90,000, and treatment with sodium dodecylsulfate cleaves the enzyme into four units with a molecular weight of about 22,000. The activity toward 28 naturally occurring esters was assayed and shown to vary considerably with substrate, the 1/1 preparation having in general higher activity than 1/2 and 2/2, which were very similar. Heat sensitivity, the effect of metal ions, and the effects of the presence or absence of an end product were also studied. The differences demonstrated between allozymes would allow considerable scope, under appropriate conditions, for differential selection to operate between genotypes.
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  • 6
    ISSN: 1573-4927
    Keywords: Drosophila melanogaster ; phosphoglucomutase ; polymorphism ; enzyme kinetics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Phosphoglucomutase (PGM) of adult stage in Drosophila melanogaster has been characterized by gel filtration, ion-exchange chromatography, and isoelectric focusing. The two common electrophoretic variants, PGMA and PGMB, differ with respect to their kinetic and stability parameters. PGMA is more thermostable than PGMB but shows the same pH optimum, equal dependence on Mg2+, and identical molecular weight. There is no significant kinetic difference between the two allozymes at the optimum pH value, but at pH 6.0 the K m value for glucose-1,6-diphosphate of PGMB is significantly higher than that of PGMA. This difference might explain the observed selective advantage of the Pgm A allele in population studies.
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  • 7
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    Biochemical genetics 17 (1979), S. 97-104 
    ISSN: 1573-4927
    Keywords: Drosophila melanogaster ; form II RNA polymerase initiation sites ; chromomeres
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract The in vitro incorporation of γ-32P-labeled nucleoside triphosphates into RNA by Drosophila melanogaster form II RNA polymerase from template sites which afford protection from the initiation inhibitor, polyriboinosinic acid (poly [I]), is used as a method for enumerating a specific class of transcription initiation sites on D. melanogaster DNA. Such sites number about 4000 per haploid genome for D. melanogaster. This value is in good agreement with the number of functional genetic units in the D. melanogaster genome as determined by classical cytogenetics.
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  • 8
    ISSN: 1573-4927
    Keywords: Drosophila melanogaster ; Malpighian tubules ; purine transport ; eye color mutants ; riboflavin
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Uptakes of guanine into Malpighian tubules of wild-type Drosophila and the eye color mutants white (w), brown (bw), and pink-peach (p p) have been compared. Tubules for each of these mutants are unable to concentrate guanine intracellularly. The transport of xanthine and riboflavin is also deficient in w tubules. The transport of guanosine, adenine, hypoxanthine, and guanosine monophosphate is similar in wild-type and white Malpighian tubules. These data and other information about these mutants make it likely that these pteridine-deficient eye color mutants do not produce pigments because of the inability to transport a pteridine precursor. This view supports the hypothesis that mutants which lack both pteridine and ommochromes do so because precursors to both classes of pigments share a common transport system.
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  • 9
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    Biochemical genetics 17 (1979), S. 149-158 
    ISSN: 1573-4927
    Keywords: xanthommatin synthesis ; scarlet mutants ; Drosophila melanogaster ; temperature-sensitive mutants
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Six new EMS-induced scarlet mutants were selected. Four of these were partially pigmented, with xanthommatin levels ranging from 12% to 45% of normal. In one (st 754ts), pigment production was temperature sensitive; the level of xanthommatin changed from less than 10% of normal at 29 C to more than 70% at 18 C. In all of the new mutants tested, the level of early pupal 3-hydroxykynurenine was as low as low as that in st 1. Thus reduced larval accumulation of this metabolite also appears to be a characteristic feature of scarlet mutants. Temperature-pulse and temperature-shift experiments were carried out with st 754ts to determine the temperature-sensitive period for the scarlet gene during development. The major sensitive period commenced prior to the onset of pigmentation and was over before adult emergence. Thus the initiation of xanthommatin synthesis is not brought about by the activation of the scarlet gene. In similar experiments carried out with a temperature-sensitive white mutant (w bl), a similar temperature-sensitive period was obtained.
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  • 10
    ISSN: 1573-4927
    Keywords: Drosophila melanogaster ; biopterin synthesis ; oxidation of dihydropterins
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract An enzyme which has been named “biopterin synthase” has been discovered in Drosophila melanogaster. This enzyme, which has been purified 200-fold from extracts of Drosophila, catalyzes the conversion of sepiapterin to dihydrobiopterin, or oxidized sepiapterin to biopterin. The K m values for the two substrates are 63 µm for sepiapterin and 10 µm for oxidized sepiapterin. NADPH is required in this enzymatic reaction. An analysis of enzyme activity during development in Drosophila indicates a correlation between enzyme activity and biopterin content at various development stages. Another enzyme, called “dihydropterin oxidase,” was also discovered and partially purified. This enzyme catalyzes the oxidation of dihydropterin compounds to the corresponding pterin compounds. For example, sepiapterin (a dihydropterin) is oxidized to oxidized sepiapterin in the presence of this enzyme. The only dihydropterin that has been tested that is not a substrate for this enzyme is dihydroneopterin triphosphate, the compound thought to be a precursor for all naturally occurring pterins and dihydropterins. Since the action of dihydropterin oxidase is reduced significantly when the concentration of oxygen is very low, it is likely that this enzyme uses molecular oxygen as the oxidizing agent during the oxidation of dihydropterins. Neither NAD+ or NADP+ is required. In the presence of the two enzymes dihydropterin oxidase and biopterin synthase, sepiapterin is converted to biopterin. However, in the presence of biopterin synthase alone, sepiapterin is converted to dihydrobiopterin.
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  • 11
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    Theoretical and applied genetics 55 (1979), S. 231-238 
    ISSN: 1432-2242
    Keywords: Drosophila melanogaster ; Scute locus ; Maps ; Operon-like model
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The functional expression of 12 scute alleles in homozygotes and compounds of Drosophila melanogaster at 14°, 22°, 30°C is analysed. Based on the data obtained, linear maps for bristles and mutations are built. The basic features of the maps, clustering and polarity, are invariable with respect to temperature, scute gene dosage and cross direction. In addition local dominance of the norm over bristle reduction was produced by the scute mutation; different types of complementation reactions were established for each bristle. The gene scute is treated as an operon-like system, composed of 3–4 cistrons with each controlling the formation of bristles on a particular region of the fly's body. This model argues well with the structure of maps constructed and implies a post-translational level of initial events of bristle-formation process.
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  • 12
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    Fresenius' Zeitschrift für analytische Chemie 298 (1979), S. 367-372 
    ISSN: 1618-2650
    Keywords: Best. von Lanthaniden, Europium, Dysprosium, Erbium, Samarium in Uran ; Spektralphotometrie ; Atomabsorption ; Graphitofen
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Summary Studies were conducted on the assay of Sm, Eu, Dy and Er separated from uranium using aqueous standards by electrothermal AAS with Massmann type graphite furnace. The working curves were found to be linear in the ranges Sm (1–10 μg/ml), Eu (0.05–0.6 μg/ml), Dy (0.1–0.8 μg/ml) and Er (0.1–1.0 μg/ml). The values obtained for synthetic samples agreed favourably with those obtained by emission spectrographic method. Experiments using pyrolytic carbon coated tubes with and without pretreatment by La, Ta and Y have shown an enhancement with treatment upto a maximum of 15% and improve the memory effect marginally. The effect of Ta treatment was found to be singularly useful in improving the general behaviour of Sm. The interference effects of lanthanides, other than the analyte, were found to be negligible. However, the presence of uranium was found to affect the absorbance. The absorbance of Eu was found to be nearly independent of uranium after an initial increase. On the other hand, the absorbance of other elements studied was found to drastically decrease after an initial enhancement. Detailed investigations of temperature dependence of absorbance were carried out using Eu, Dy and Er. The differences in the behaviour of these elements is attributed to probable differences in the modes of their atomization.
    Notes: Zusammenfassung Die Untersuchungen wurden mit Hilfe des Graphitrohrofens nach Maßmann durchgeführt. In folgenden Bereichen ergaben sich lineare Eichkurven: Sm 1–10 μg/ml, Eu 0,05–0,6 μg/ml, Dy 0,1–0,8 μg/ml, Er 0,1μ-1,0 μg/ml. Die aus synthetischen Proben erhaltenen Ergebnisse stimmten gut mit den durch Emissionsspektrographie erhaltenen überein. Versuche wurden mit Röhren mit pyrolytischen Kohlenstoffüberzug mit und ohne Vorbehandlung durch La, Ta und Y durchgeführt und ergaben eine bis 15%ige Steigerung durch die Behandlung sowie eine mäßige Besserung des Memoryeffektes. Eine Behandlung mit Ta war besonders für Sm vorteilhaft. Störungen durch andere Lanthanide waren vernachlässigbar. Uran beeinflußte jedoch die Absorption. Im Falle von Eu zeigte sich nach anfänglicher Zunahme fast eine Unabhängigkeit, während bei den anderen untersuchten Elementen nach anfänglicher Zunahme eine beträchtliche Abnahme auftrat. Mit Eu, Dy und Er wurde ebenfalls die Temperaturabhängigkeit der Absorption untersucht. Festgestellte Unterschiede im Verhalten werden auf unterschiedliche Atomisierung zurückgeführt.
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  • 13
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    Fresenius' Zeitschrift für analytische Chemie 294 (1979), S. 284-284 
    ISSN: 1618-2650
    Keywords: Best. von Uran(VI) mit Chlorphosphonazo III ; Spektralphotometrie ; Trioctylamin-Extraktion
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
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  • 14
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    Fresenius' Zeitschrift für analytische Chemie 294 (1979), S. 285-285 
    ISSN: 1618-2650
    Keywords: Best. von Phosphat in Ferrosilicium ; Spektralphotometrie ; Cer/Xylenolorange, indirekt
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
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  • 15
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    Fresenius' Zeitschrift für analytische Chemie 294 (1979), S. 413-413 
    ISSN: 1618-2650
    Keywords: Best. von Kobalt mit Pyridin und Azid ; Spektralphotometrie ; Aussalzungsmittel, Mischkomplex
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
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  • 16
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    Fresenius' Zeitschrift für analytische Chemie 295 (1979), S. 270-270 
    ISSN: 1618-2650
    Keywords: Best. von Cer(IV) ; Spektralphotometrie ; indirekt, Fe(III)-Resacetophenonoximat-Komplex
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    Topics: Chemistry and Pharmacology
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  • 17
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    Fresenius' Zeitschrift für analytische Chemie 299 (1979), S. 264-266 
    ISSN: 1618-2650
    Keywords: Best. von Kohlenhydraten in Huminsäuren ; Spektralphotometrie ; Anthronmethode
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Eine modifizierte Anthronmethode zur Bestimmung des Kohlenhydratgehaltes in Fraktionen von Huminsäure-Blei(II)-Chelatverbindungen, die mit chemischen und gelchromatographischen Methoden getrennt wurden, wird beschrieben. Um die Störung der Methode durch die Absorption der Huminsäuren, die mit abnehmender Wellenlänge ansteigt, gering zu halten, wird die Extinktion des Anthron-Kohlenhydrat-Reaktionsproduktes bei 620 nm gemessen. Die Huminsäurekonzentration darf 0,1 g/dl nicht überschreiten. Da die molare Extinktion des Anthron-Reaktionsproduktes von der Art des Kohlenhydrates abhängt, wird der Kohlenhydratgehalt auf das Hauptkohlenhydrat des Huminsäurehydrolysats berechnet (d.h. Glucose).
    Notes: Summary A modified anthrone method is described for the determination of carbohydrates in fractions of lead(II)-chelate compounds of humic acids separated with chemical as well as gel-chromatographic methods. To reduce the disturbance of the method by the absorption of humic acids increasing with the decrease of wavelength, the absorbance of the anthronecarbohydrate reaction products is measured at 620 nm and the humic acid concentration is not allowed to exceed 0.1 g/dl. Because the molar absorptivity of the anthrone reaction-products depends on the type of carbohydrate investigated, the content is calculated for the main carbohydrate of the humic-acid hydrolysate (i.e. glucose).
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  • 18
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    Fresenius' Zeitschrift für analytische Chemie 295 (1979), S. 366-370 
    ISSN: 1618-2650
    Keywords: Best. von Quecksilber, Silber mit Formazanen ; Spektralphotometrie ; chelatbildende Ionenaustauscher
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Die Darstellung substituierter Formazane und ihre chemische Fixierung an Cellulose, amino- und chlormethyliertem Polystyrol wird beschrieben. Die Kapazitäten der Austauscher liegen zwischen 0,05 mÄq/g (Cellulose) und 0,6 mÄq/g (Polystyrol). In neutralem Medium zeigen sie eine besondere Affinität zu Hg(II), Pd(II) und Ag(I), aber keine Affinität zu Cu(II). Weiterhin wurde eine spektrophotometrische Bestimmung von Hg(II) und Ag(I) mit dem wasserlöslichen Formazan (FII)-NO2 ausgearbeitet [Hg(II): ɛ546=23 000 l Mol−1 cm−1, Ag(I): ɛ546 =38 000 l Mol−1 cm−1].
    Notes: Summary The preparation of substituted formazans and their fixation on cellulose, amino- and chloromethylated polystyrene is described. The capacities of the exchangers vary from 0.05 meq/g (cellulose) to 0.6 meq/g (polystyrene). They show in neutral medium greater affinity to Hg(II), Pd(II) and Ag(I), but no affinity to Cu(II). Further, a spectrophotometric determination of Hg(II) and Ag(I) with the watersoluble formazan (FII)-NO2 has been worked out. [Hg(II): ɛ546=23 000 l Mol−1 cm−1, Ag(I): ɛ546=38 000 l Mol−1 cm−1].
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  • 19
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    Fresenius' Zeitschrift für analytische Chemie 294 (1979), S. 356-360 
    ISSN: 1618-2650
    Keywords: Spektralphotometrie ; Mechanisierung, Prinzip, Optimierung
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Das Prinzip der Automatisierung der photometrischen Analyse mit kontinuierlichem Reagentienfluß und die speziellen Vorteile der Verwendung von Bausteinen der Flüssigkeits-Chromatographie werden ausführlich diskutiert. Die Optimierung folgender Parameter wird besprochen: Verweilzeit (Reaktionszeit), Einspritzmenge, Pumpgeschwindigkeit, Säulenabmessungen, Partikeldurchmesser.
    Notes: Summary The principle of automation of photometric analysis by the continuous flow method and the particular advantages of the use of component parts of liquid chromatography are discussed in detail. The optimization of the following parameters is pointed out: residence (reaction) time, injection volume, pumping rate, column dimensions and particle diameter.
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  • 20
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    Fresenius' Zeitschrift für analytische Chemie 295 (1979), S. 47-47 
    ISSN: 1618-2650
    Keywords: Best. von Vanadium in Stahl ; Spektralphotometrie ; Hydroxyphenyl-p-tolylbenzamidin
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
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  • 21
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    Fresenius' Zeitschrift für analytische Chemie 295 (1979), S. 393-397 
    ISSN: 1618-2650
    Keywords: Best. von Tensiden in Wasser ; Spektralphotometrie ; Aniontenside, Reinigungsstufen
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Aniontenside werden an Feststoffen der Gewässer wie auch der Kläranlagen adsorbiert und teilweise angereichert. Ihre analytische Bestimmung erfordert eine mehrstufige Vorarbeit. Sie führt über die Extraktion des Probengutes, die Abtrennung der Tenside von Störstoffen durch Ausblasen (grobe Vorreinigung) und die chromatographische Reinigung der Rohfraktion auf Kieselgelschichten. Die Konzentration der reinen Tensidfraktion kann colorimetrisch oder IR-spektrometrisch bestimmt werden.
    Notes: Summary Anion tensides are adsorbed on solids in surface waters and sewage treatment plants and enriched to some extent. Their analytical determination requires multi-stage preparations, including sampling, separation of the tensides from disturbing material by air stripping (rough preliminary cleaning), and chromatographic cleaning of the raw fraction on silica gel. The concentration of the pure tenside fraction can be determined colorimetrically or by way of IR spectrometry.
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  • 22
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    Fresenius' Zeitschrift für analytische Chemie 297 (1979), S. 159-160 
    ISSN: 1618-2650
    Keywords: Best. von Vanadium(V) mit p-Hydroxybenzaldehyd und Hydroxyamidin ; Spektralphotometrie
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    Topics: Chemistry and Pharmacology
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  • 23
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    Fresenius' Zeitschrift für analytische Chemie 298 (1979), S. 158-158 
    ISSN: 1618-2650
    Keywords: Best. von Palladium, Ruthenium ; Spektralphotometrie ; Isonitrosodibenzoylmethan
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    Topics: Chemistry and Pharmacology
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  • 24
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    Fresenius' Zeitschrift für analytische Chemie 298 (1979), S. 160-160 
    ISSN: 1618-2650
    Keywords: Best. von Ruthenium(III) mit 3-Hydroxy-3-(p-dimethylaminophenyl)-1-phenyltriazen ; Spektralphotometrie
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  • 25
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    Fresenius' Zeitschrift für analytische Chemie 296 (1979), S. 45-45 
    ISSN: 1618-2650
    Keywords: Best. von o-Dichlorbenzol ; Spektralphotometrie ; UV
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  • 26
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    Fresenius' Zeitschrift für analytische Chemie 296 (1979), S. 46-46 
    ISSN: 1618-2650
    Keywords: Best. von p-Methylaminophenolsulfat, Metol ; Spektralphotometrie
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    Topics: Chemistry and Pharmacology
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  • 27
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    Fresenius' Zeitschrift für analytische Chemie 296 (1979), S. 406-407 
    ISSN: 1618-2650
    Keywords: Best. von Ligninsulfonsäure, Huminsäure in Wasser ; Spektralphotometrie ; UV
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    Fresenius' Zeitschrift für analytische Chemie 296 (1979), S. 383-385 
    ISSN: 1618-2650
    Keywords: Best. von Bor in Silicaten ; Spektralphotometrie ; Pyrohydrolyse, Carminsäure
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    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Summary This simple method for the determination of boron takes a total time of 20 min. Samples are mixed with CaF2 suprapur in the ratio 3∶1 and pyrohydrolized in a Leco induction furnace for 15 min under steam of H2O. The BF3 liberated is collected in a NaOH-Na2CO3 solution (10 g NaOH +1 g Na2CO3 per liter). This solution is filled up to 200 ml with twice distilled water; 2 ml of this solution is mixed with conc. sulphuric acid and carminic acid solution and filled up to 50 ml. The absorption is measured by a Zeiss Elko II photometer with filter S 59. Analyses of four internations reference samples show excellent precision with a relative standard deviation of less than 5% (e.g. for a boron content of 2.1 ppm in granite G-2).
    Notes: Zusammenfassung Die Borbestimmung mit dieser schnellen und einfachen Methode benötigt ca. 20 min. Die Proben werden mit CaF2 Suprapur im Verhältnis 3∶1 vermischt und in einem Leco-Induktionsofen 15 min unter Einleitung von Wasserdampf pyrohydrolysiert. Das entstandene BF3 wird in einer NaOH-Na2CO3-Lösung(10 g NaOH+1 gNa2CO3pro Liter) aufgefangen. Diese Lösung wird mit zweifach destilliertem Wasser auf 200 ml aufgefüllt; 2 ml dieser Lösung werden mit konz. Schwefelsäure und Carminsäure-Lösung versetzt und auf 50 ml aufgefüllt, bevor ihre Absorption mit einem Zeiss — Elko II — Photometer mit Filter S 59 gemessen wird. Analysen von 4 internationalen Referenzproben zeigen eine hohe Präzision mit einer relativen Standardabweichung von weniger als 5% (z. B. für einen Gehalt von 2,1 ppm Bor im Granit G-2 des USGS).
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    Fresenius' Zeitschrift für analytische Chemie 296 (1979), S. 407-408 
    ISSN: 1618-2650
    Keywords: Best. von N-p-Tolylbenzohydroxamsäure ; Spektralphotometrie
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    Fresenius' Zeitschrift für analytische Chemie 296 (1979), S. 414-415 
    ISSN: 1618-2650
    Keywords: Best. von Quecksilber(II) mit 3-Methyl-5-pyrazolon-4-dithiocarbonsäure ; Spektralphotometrie
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    Behavior genetics 9 (1979), S. 123-128 
    ISSN: 1573-3297
    Keywords: Drosophila melanogaster ; phototaxis ; X chromosome
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    Topics: Biology , Psychology
    Notes: Abstract Strains ofDrosophila melanogaster differ in their phototactic responses to red light (654 nm). Genes located on all three major chromosomes are involved in influencing the response, but the X chromosome and third chromosome account for most of the variation in phototaxis.
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    Behavior genetics 9 (1979), S. 129-134 
    ISSN: 1573-3297
    Keywords: Drosophila melanogaster ; D. simulans ; larval feeding behavior ; egg-to-adult viability ; isofemale line
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    Topics: Biology , Psychology
    Notes: Abstract Larval feeding behavior of isofemale lines of the sibling speciesDrosophila melanogaster andD. simulans was investigated. This behavior was measured as the number of cephalopharyngeal retractions of individual larvae per 30 sec period (CPR score) in different generations (G0, G1, and G14). In addition, egg-to-adult viability was estimated in each isofemale line. The results were as follows: (1) In either species, there was variation of CPR score among individuals and among isofemale lines. Although no differences of CPR score were found among experimental groups (generations) and between species, there was a significant difference among isofemale lines. (2) The behavioral trait was stable through generations in each isofemale line. (3) This behavior was correlated with egg-to-adult viability, showing that it is important for the development of the fly.
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    Behavior genetics 9 (1979), S. 209-217 
    ISSN: 1573-3297
    Keywords: Drosophila melanogaster ; D. simulans ; D. pseudoobscura ; pupation height ; geotaxis ; species differences ; selection for pupation height
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    Topics: Biology , Psychology
    Notes: Abstract Pupation heights of various natural and laboratory populations ofDrosophila melanogaster, D. simulans, andD. pseudoobscura were observed in the laboratory under conditions of continuous darkness or continuous light. Generally higher mean pupation heights were observed under conditions of darkness.D. melanogaster tended to pupate higher than theD. pseudoobscura populations, andD. pseudoobscura tended to pupate higher thanD. simulans. The order of these species differences was similar whether pupation was measured in light or in darkness. Results of selection for pupation height inD. melanogaster suggest the presence of genetic variation for this character. The possibility that a relationship exists between adult and larval behaviors was explored by measuring the pupation heights of larvae from strains selected for geotactic behavior as adults, and also by measuring geotaxis of adults from strains selected for pupation height.
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    Behavior genetics 9 (1979), S. 257-275 
    ISSN: 1573-3297
    Keywords: sexual behavior ; Drosophila melanogaster ; genetic mosaics ; ontogeny of behavior ; wing vibration
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    Topics: Biology , Psychology
    Notes: Abstract The sex appeal of aDrosophila melanogaster female is defined here as the stimulus (or set of stimuli) which induces wing vibration in courting males. A quantitative measure of sex appeal is the cumulative duration of wing vibration induced by a given female averaged over several consecutive test intervals using different standardized male testers (sex appeal parameter, SAP). By use of SAP, both males and females are found to have the same amount of sex appeal on the first day after eclosion. However, males rapidly lose it by the next day, so that mature males become distinct from females. We report the ontogeny of the male's response to sex appeal. By the SAP method, we also demonstrate that the male's response is dependent on his previous encounter with females. The sex appeal of 287 gynandromorphs was examined in order to localize the sex appeal focus by means of blastoderm fate mapping. Most mosaic flies were classified as either positive (femalelike, with high SAPs) or negative (malelike, with SAPs of zero). Sixteen percent of the gynandromorphs had intermediate levels of SAP, inducing only short vibrations, a response which males rarely give to normal females. Assuming that the gynanders with such intermediate sex appeal must have both female and male foci, distances to the foci from external landmarks were calculated. The center of the focus seems to be an internal structure mapping to the ventroposterior region of the blastoderm fate map, close to the primordia of the anterior sternites. The focus might include a large mesodermal area, but only part of it must have a female genotype for the sex appeal to be expressed. A possible involvement of the fat bodies in production of the sex appeal stimulus is discussed in relation to these findings. Consistent with this conclusion is the fact that females whose abdomens were amputated still retain enough sex appeal to induce male wing vibrations.
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    ISSN: 1573-3297
    Keywords: aristal morphology ; Drosophila melanogaster ; artificial selection ; geotaxis ; mating behavior
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    Topics: Biology , Psychology
    Notes: Abstract The aristae ofDrosophila have been shown to play a role in mating behavior and geotaxis. Two populations ofD. melanogaster were selected for increased and decreased numbers of major aristal branches. Selection was successful and resulted in two lines differing by an average of six aristal branches. Hybridization analyses of selected lines revealed that genes influencing aristal branching are located on both the X chromosome and the autosomes. Polygenic control of aristal morphology is indicated by a gradual response to selection and low realized heritabilities. When selection was relaxed for 19 generations, the number of aristal branches did not revert to the number in the control line. Changes in aristal branching did not appear to have a consistent influence on geotaxis, although there was a tendency for flies with fewer aristal branches to be geonegative. Neither mating speed nor ethological isolation between the two populations was affected by selection. It is concluded that the number of aristal branches inDrosophila is a neutral trait (i.e., not subject to natural selection) under laboratory conditions. Correlations between aristal morphology and behavior found in other selection experiments by previous investigators were likely due to linkage disequilibria.
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    Behavior genetics 9 (1979), S. 407-412 
    ISSN: 1573-3297
    Keywords: Drosophila melanogaster ; oviposition site preference ; substrate temperature ; heritability
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    Topics: Biology , Psychology
    Notes: Abstract Drosophila melanogaster females from a multifemale stock (SC-1) showed strong oviposition site preference (OSP) in a continuous gradient of substrate temperatures (18–31°C). Flies reared at 25°C had an OSP ( $$\bar X$$ ±SE) of 25.2±0.2°C, whereas flies reared at 18°C had an OSP of 23.5±.2°C. Flies reared from egg to adult at one temperature and exposed as adults for 4 days to another temperature had OSPs intermediate between these extremes. This second 4-day exposure seemed to have a greater effect on OSP than the first rearing temperature. Selection experiments failed to produce significant change in mean OSP in eight generations, indicating a low heritability of temperature OSP in this stock.
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    Behavior genetics 9 (1979), S. 425-429 
    ISSN: 1573-3297
    Keywords: random mating ; Drosophila pseudoobscura ; pheromones ; Drosophila melanogaster
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    Topics: Biology , Psychology
    Notes: Abstract Inbreeding, up to 12 generations of single-pair matings, did not cause significant deviation from random mating among two sets of strains inDrosophila pseudoobscura. This contrasts with reports that inbreedingD. melanogaster induces negative assortative mating among lines.
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    Behavior genetics 9 (1979), S. 543-553 
    ISSN: 1573-3297
    Keywords: Drosophila melanogaster ; divergent selection ; locomotor activity ; heritability
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    Topics: Biology , Psychology
    Notes: Abstract Selection for high and low locomotor activity has been applied in two base populations ofDrosophila melanogaster of distinct geographical origin. From each base population a high and a low line were selected, in which anesthesia was performed with ether. In addition, from one of the base populations a high line and a low line were selected under CO2 narcosis. Locomotor activity was measured in an apparatus consisting of rows of 20 tubes in a line. Heritabilitities in the base populations determined in progeny tests were approximately 10%. Divergent directional selection was successful with realized heritabilities of similar value.
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    ISSN: 1573-3297
    Keywords: Drosophila melanogaster ; locomotor activity ; mating preference ; sexual isolation ; fertility ; selected lines
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    Topics: Biology , Psychology
    Notes: Abstract Tests for reproductive isolation between lines selected for locomotor activity were performed. Three sets of selection lines were used, each consisting of lines selected for low and high locomotor activity from the same base population. Females preferred high-activity males in almost every case. However, in one of the sets temporary sexual isolation was found between flies of the high and low lines. This was accompanied in the low-activity females with a higher fertility when they were mated with their own males. After further selection the partial isolation disappeared.
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    Behavior genetics 9 (1979), S. 563-570 
    ISSN: 1573-3297
    Keywords: Drosophila melanogaster ; locomotor activity ; genetic analysis ; X chromosome ; selected lines
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    Topics: Biology , Psychology
    Notes: Abstract Divergent directional selection produced three pairs of lines each consisting of a line with high and a line with low locomotor activity. Reciprocal crosses between the high and low lines of one of these pairs showed that a considerable part of the activity differences was contributed by differences between the X chromosomes. This was confirmed by a substitution of the three large chromosomes, between the low and the high lines. The two large autosomal chromosomes had only minor effects. Interactions between chromosomes were sometimes significant. Low-activity alleles tended to be dominant over alleles for high activity.
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    Fresenius' Zeitschrift für analytische Chemie 294 (1979), S. 286-286 
    ISSN: 1618-2650
    Keywords: Best. von Aminen mit Isothiocyanatodioxotolyldihydrobenzisochinolin ; Spektralphotometrie
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    Topics: Chemistry and Pharmacology
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    Fresenius' Zeitschrift für analytische Chemie 294 (1979), S. 285-285 
    ISSN: 1618-2650
    Keywords: Best. von Eisen(III), Chrom(VI) mit Helasolviolett 4R ; Spektralphotometrie
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    Fresenius' Zeitschrift für analytische Chemie 295 (1979), S. 119-121 
    ISSN: 1618-2650
    Keywords: Best. von Wolfram(VI) mit Thioglykolsäure ; Spektralphotometrie ; Chelatbildung, Carbonsäuren
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    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung W(VI) bildet mit Thioglykolsäure und Glykolsäure mäßig stabile Fünfringchelate der Zusammensetzung WR2, mit Glycin ein sehr schwaches WR. Chelate mit den Sechsringbildnern 3-Mercaptopropionsäure und o-Mercaptobenzoesäure sind nicht nachweisbar. Das Thioglykolsäurechelat kristallisiert aus Methanol als gelbes Na-Salz WO2(SCH2COONa)2·2CH3OH und ist mit Di-phenylguanidin als Ionenpaar in Butanol extrahierbar. Die photometrische Wolframbestimmung mit Thioglykolsäure in wäßriger Lösung erreicht eine Bestimmungsgrenze von $$\underline c $$ = 0,92 ppm W (P=99,9%;M=2) und eine Standardabweichung vons=0,24 ppm W (f=21).
    Notes: Summary W(VI) forms moderately stable, five-membered ring chelates of the composition WR2 with thioglycolic and glycolic acid, and a very weak WR with glycine. Chelation with the six-ring forming 3-mercaptopropionic acid and o-mercaptobenzoic acid could not be detected. The chelate with thioglycolic acid crystallizes from methanol as the yellow sodium salt WO2(SCH2COONa)2·2CH3OH and can be extracted into butanol as an ion pair with diphenylguanidine. The photometric determination of tungsten with thioglycolic acid has a determination limit of $$\underline c $$ = 0.92 ppm W (P=99.9%;M=2) and a standard deviations=0.24 ppmW (f=21).
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    Fresenius' Zeitschrift für analytische Chemie 295 (1979), S. 122-124 
    ISSN: 1618-2650
    Keywords: Best. von Sulfat in Umweltmaterial ; Wasser ; Spektralphotometrie ; Durchflußsystem
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    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Summary Sulphate in various environmental samples was determined by measuring the optical absorbance upon reaction with the barium(II) dimethylsulphonazo(III) complex. The measurement took place in a flow-through system. Interferences from phosphate, metal ions and others were eliminated. The results of a turbidimetric measurement, a spectrophotometric measurement with thorin, an automatic titration and the proposed method are compared. The latter allows the determination of sulphate in the range of 1.4–60 μmol·l−1. The standard deviation is 0.3–0.6 μmol·l−1, depending on the type of sample (water) analysed. A determination takes 1.5min.
    Notes: Zusammenfassung Sulfat wurde in verschiedenen Umweltproben durch Messung der Extinktion nach Reaktion mit dem Barium(II)-dimethylsulfonazo(III)-komplex im Durchflußsystem bestimmt. Störungen von Phosphat, Metallionen, u.a. wurden beseitigt. Die Ergebnisse einer turbidimetrischen, einer photometrischen, einer automatischen Titration und der vorgeschlagenen Methode werden verglichen. Die Methode ermöglicht die Sulfatbestimmung im Bereich von 1,4–60 μmol·l−1. Die Standardabweichung beträgt 0,3–0,6 μmol· l−1 je nach Typ des Probematerials (Wasser). Eine Bestimmung erfordert 1,5min.
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    Fresenius' Zeitschrift für analytische Chemie 295 (1979), S. 271-271 
    ISSN: 1618-2650
    Keywords: Best. von Blei in Wasser, Abwasser, Staub ; Spektralphotometrie ; Dithizon
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    Fresenius' Zeitschrift für analytische Chemie 295 (1979), S. 413-413 
    ISSN: 1618-2650
    Keywords: Best. von Platin(IV) mit Chlorpromazin ; Spektralphotometrie
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    Fresenius' Zeitschrift für analytische Chemie 297 (1979), S. 419-419 
    ISSN: 1618-2650
    Keywords: Spektralphotometrie ; Bouguer-Lambert-Beersches Gesetz, neues Konzept
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    Fresenius' Zeitschrift für analytische Chemie 298 (1979), S. 160-160 
    ISSN: 1618-2650
    Keywords: Best. von Phenothiazinen ; Spektralphotometrie ; Silicowolframsäure
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    Fresenius' Zeitschrift für analytische Chemie 294 (1979), S. 43-44 
    ISSN: 1618-2650
    Keywords: Best. von Salicylaldehyd ; Spektralphotometrie ; konz. Schwefelsäure
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    Fresenius' Zeitschrift für analytische Chemie 294 (1979), S. 46-46 
    ISSN: 1618-2650
    Keywords: Best. von Osmium mit N-Benzoyl-o-tolylhydroxylamin ; Spektralphotometrie
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    Fresenius' Zeitschrift für analytische Chemie 294 (1979), S. 415-416 
    ISSN: 1618-2650
    Keywords: Best. von Albumin in Serum ; Spektralphotometrie ; Isothiocyanatodioxo-tolyldihydro-benzisochinolin, Rinderserum
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    Fresenius' Zeitschrift für analytische Chemie 299 (1979), S. 128-128 
    ISSN: 1618-2650
    Keywords: Best. von Ruthenium mit 2-Methyl-1,4-naphtochinon-monoxim ; Spektralphotometrie ; Extraktion
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    Fresenius' Zeitschrift für analytische Chemie 295 (1979), S. 412-413 
    ISSN: 1618-2650
    Keywords: Best. von Palladium(II), Ruthenium(III) mit Isonitrosobenzoylacetone ; Spektralphotometrie
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    Fresenius' Zeitschrift für analytische Chemie 297 (1979), S. 384-387 
    ISSN: 1618-2650
    Keywords: Best. von Uran ; Spektralphotometrie ; Spuren, Extraktion mit Triphenylarsinoxid in Chloroform
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    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Es wurde eine einfache, vielseitig anwendbare spektralphotometrische Uranbestimmung für U6+-Mengen bis in den ng-Bereich ausgearbeitet, bei der über 60 Kationen und etwa 20 Anionen in weiten Grenzen nicht stören. Das mit Triphenylarsinoxid in CHCl3 aus der zu untersuchenden Lösung extrahierte Uran wird mit oxalsäurehaltiger 5,5 M HClO4 zurückextrahiert und in den Arsenazo III-Komplex überführt. Die mit diesem Schritt verbundene Aufkonzentrierung erlaubt noch bis zu 0,01 μg Uran in 200 ml Ausgangslösung spektralphotometrisch bei 655 nm zu bestimmen. Im günstigsten Arbeitsbereich beträgt die relative Standardabweichung ±1%. 4 Probelösungen können in 1 h analysiert werden.
    Notes: Summary A simple and versatile spectrophotometric method for the determination of uranium down to the μg range was worked out. About 60 cations and 20 anions were found not to cause interferences in a wide concentration range. U6+ is extracted with triphenylarsine oxide in chloroform, back-extracted with 5.5 M perchloric acid containing oxalic acid and converted to the arsenazo III-complex. The concentration step involved allows the spectrophotometric determination of 0.01 μg of uranium in 200 ml of original solution at 655 nm. A standard deviation of ±1 % can be achieved and it is possible to analyse about 4 solutions per hour.
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    Fresenius' Zeitschrift für analytische Chemie 298 (1979), S. 156-157 
    ISSN: 1618-2650
    Keywords: Best. von Sulfat in Wasser ; Spektralphotometrie ; Ionenaustausch, Dimethylsulfonazo(III)
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    Fresenius' Zeitschrift für analytische Chemie 298 (1979), S. 150-154 
    ISSN: 1618-2650
    Keywords: Best. von Kupfer mit Fluoronen ; Spektralphotometrie ; Übersicht über die Fluorone
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    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Fluorone, Verbindungen des 2,3,7-Trihydroxyisoxanthenons-(6), eignen sich als empfindliche Reagentien für die spektralphotometrische Analyse zahlreicher Metallionen im sichtbaren Teil des Spektrums. Neben einigen grundsätzlichen Anmerkungen zur Herstellung, zu den Eigenschaften und Reaktionen der Fluorone mit Metallionen wird die Verwendung des Cyclohexylfluorons (CHF) für die photometrische Bestimmung von Cu(II)-Ion beschrieben; hierbei ergibt sich ein molarer Extinktionskoeffizient von 191000 l/Mol · cm und eine Standardabweichung von ±0,2 ng/ml. Der Anwendungsbereich liegt bei 6–60 ng Cu/ml. Bi, Fe(II/III) und Sb müssen zuvor abgetrennt werden.
    Notes: Summary Fluorones, derivates of 2,3,7-trihydroxyisoxanthenone-(6), are sensitive reagents for the spectrophotometric determination of many metal ions in aqueous solution. Besides some principal remarks on the synthesis, properties and reactions of fluorones, the application of cyclohexylfluorone for the determination of Cu(II) ion is described in detail. This method is applicable in the concentration range 6–60 ng of Cu/ml. The molar absorptivity is 1910001/Mol · cm and the standard deviation is ±0.2 ng/ml. Bi, Fe(II, III) and Sb have to be separated prior to the determination.
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    Development genes and evolution 184 (1978), S. 41-56 
    ISSN: 1432-041X
    Keywords: Drosophila melanogaster ; Female germ line ; Mosaics ; Stem cell divisions ; Metafemale ; Sterility
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    Topics: Biology
    Notes: Summary Our report presents an analysis of the development and dynamics of the female germ line inDrosophila. Females were produced that were mosaic either for attached-X chromosomes $$(\widehat{XX})$$ and a ring-X (triplo-X-diplo-X), or for $$\widehat{XX}$$ and a marked Y-chromosome $$(\widehat{XX}/Y - \widehat{XX}/O)$$ . The germ-line and genitalia of these females were analysed by direct microscopic observation or by examination of the progeny. Eggs derived from triplo-X germ cells were hardly capable of supporting development, with most of the zygotes dying during embryonic development. The analysis of the germ line was therefore carried out mainly by direct observation of histochemically stained developing oocytes in the ovaries of mosaic females. The total germ cell population of both ovaries of a female was mosaic in 22–29% of the tested animals. From this frequency of mosaicism we estimated the number of functional primordial germ cells to be betwen 3 and 6 cells at the blastoderm stage. At this stage the cell lineages for the left and right ovary are not yet separated. The germ cell population of individual ovarioles was frequently mosaic which shows that the few stem cells in an ovariole are recruited as a group and are not clonal descendants of a single ancestor cell per ovariole. An analysis of the sequential pattern of oocyte-nurse cell cysts in mosaic ovarioles revealed that neighbouring cysts tend to be of the same genotype. This suggests that the stem cells of the adult ovaries preferentially divide in bursts, one of them giving rise to two, three and sometimes even more cystocytes in a row. In addition, the foci for lethality and sterility of the triplo-X condition were determined. Non-mosaic triplo-X females (metafemales) are hardly viable and invariably sterile. Using our mosaics, the focus forlethality could be mapped to a region very near the ventral prothoracic discs. The focus forsterility resides in the genitalia, since flies with triplo-X genitalia never laid any eggs, regardless of the genotype of their ovaries.
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  • 58
    ISSN: 1573-4927
    Keywords: Drosophila melanogaster ; GTP cyclohydrolase ; development ; pteridine biosynthesis ; mutants
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    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract The reaction catalyzed by GTP cyclohydrolase is the first unique step of pteridine biosynthesis in Drosophila melanogaster and is therefore likely to be an important control point. GTP cyclohydrolase activity varies during development, showing two distinct peaks of activity—one at pupariation and a much larger peak at emergence. Most of the early pupal enzyme is located in the body region, whereas in late pupal and early adult life most of the activity is found in the head. Mixing experiments indicate that developmental changes in activity are not due to changes in the level of a direct effector of GTP cyclohydrolase. The mutants raspberry and prune show an increased GTP cyclohydrolase activity at pupariation relative to wild type, but a decreased enzyme activity at emergence. The changes in GTP cyclohydrolase activity are reflected in changes in pteridine levels in these mutants. Several lines of evidence suggest that neither locus is the structural gene for GTP cyclohydrolase. The raspberry and prune gene products may play a specific role in regulating GTP cyclohydrolase activity during development.
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  • 59
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    Biochemical genetics 16 (1978), S. 1113-1134 
    ISSN: 1573-4927
    Keywords: Drosophila melanogaster ; isozymes ; position effect ; segmental aneuploidy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract A deoxyribonuclease, called DNase-1, that is active at acid pH in the presence of EDTA has been studied in Drosophila melanogaster. The locus for the enzyme maps genetically to 61.8 on the right arm of the third chromosome. Cytogenetically, DNase-1 has been localized to within five to ten bands between 90C-2 and 90E. This analysis utilizes both electrophoretic variants and the Y-autosome translocations of Lindsley et al. (1972). DNase-1 is present in all stages of the life cycle, and the paternal genome actively contributes DNase-1 to the embryo between 0 and 1 hr after fertilization.
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  • 60
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    Biochemical genetics 16 (1978), S. 159-170 
    ISSN: 1573-4927
    Keywords: alcohol dehydrogenase ; allozyme properties and amounts ; Drosophila melanogaster
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    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Among strains of Drosophila melanogaster each derived from a single fertilized female taken from natural populations, there is variation in both alcohol dehydrogenase (ADH) activity and the amount of ADH protein. The correlation between ADH activity and number of molecules over all strains examined is 0.87 or 0.96 in late third instar larvae depending on whether the substrate is 2-propanol or ethanol. With respect to the two common electrophoretic allozymic forms, F and S, segregating in these populations, the FF strains on the whole have higher ADH activities and numbers of ADH molecules than the SS strains. Over all strains examined, enzyme extracts from FF strains have a mean catalytic efficiency per enzyme molecule higher than that of enzyme extracts from SS strains when ethanol is the substrate, and much higher when 2-propanol is the substrate. One FF strain had an ADH activity/ADH protein ratio characteristic of SS strains.
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  • 61
    ISSN: 1573-4927
    Keywords: Drosophila melanogaster ; alcohol tolerance ; alcohol utilization ; alcohol dehydrogenase ; aldehyde oxidase ; allozymes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Alcohol dehydrogenase is necessary for ethanol detoxification and metabolic utilization. It has been generally assumed that aldehyde oxidase (AO) produced by the Aldox locus (3–56.7) is necessary for a further transformation of acetaldehyde into acetate. We find that various mutant strains (ma-l or Aldox n) which do not produce an active enzyme show about the same tolerance to alcohol as do wild strains. This physiological paradox is probably to be explained by the discovery of another locus (not localized) which produced a small amount of AO in all tested strains. The adaptive significance of the genetically polymorphic Aldox locus is probably to be looked for in physiological pathways other than ethanol metabolism.
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  • 62
    ISSN: 1573-4927
    Keywords: nonelectrophoretic structural variability ; Drosophila melanogaster ; phosphoglucomutase ; genetic polymorphism ; heat denaturation study
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract A simple procedure is described to detect genetic heterogeneity within electrophoretic classes at a locus in Drosophila, based on electrophoresis and heat denaturation studies. Temperature-resistant (tr) and temperature-sensitive (ts) isoelectrophoretic alleles at the phosphoglucomutase locus (Pgm) are present at polymorphic frequencies in natural and in laboratory populations of Drosophila melanogaster.
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  • 63
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    Biochemical genetics 16 (1978), S. 333-342 
    ISSN: 1573-4927
    Keywords: β-hydroxy acid dehydrogenase ; chromosome ; dosage compensation ; Drosophila melanogaster
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract A mutant Had nl was induced in Drosophila melanogaster and found to be deficient in β-hydroxy acid dehydrogenase. This mutation was utilized to study the genetics and physiological expression of Had +. Had+ was mapped to the X chromosome at 54.4 and seems to be the structural gene for the enzyme. Enzyme activity in male and female flies indicates that the gene shows both dosage compensation independent from dose effect and differential activity during ontogeny. Electrophoretic mobility data indicate that the enzyme is a dimer which forms by random association of subunits. The fact that the mutant shows no detrimental effect implies that the enzyme is dispensable, at least under laboratory conditions. The biological and technical implications of this gene-enzyme system are discussed.
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  • 64
    ISSN: 1573-4927
    Keywords: Drosophila melanogaster ; 6-phosphogluconate dehydrogenase ; Pgd n lethal alleles ; rescue by dietary supplements ; hexose monophosphate shunt
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract The genetic rescue of Pgd n lethal alleles, accomplished by combining them with mutations lacking glucose-6-phosphate dehydrogenase activity, has led to the hypothesis that Pgd n lethality may be due to the accumulation of 6-phosphogluconate. In this article we report the rescue of Pgd n /Y males by dietary supplements (fructose and linolenate) designed to minimize 6-phosphogluconate production.
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  • 65
    ISSN: 1573-4927
    Keywords: Drosophila melanogaster ; 6-phosphogluconolactonase ; hexose monophosphate shunt ; Pgd n Zw n mutants
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Using a double mutant strain, Pgd n Zw n , we have developed an assay for 6-phosphogluconolactonase activity and have demonstrated its occurrence in adult Drosophila melanogaster.
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  • 66
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    Biochemical genetics 16 (1978), S. 769-775 
    ISSN: 1573-4927
    Keywords: hidden variation ; α-GPDH ; Drosophila melanogaster
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract The level of hidden variation in populations of Drosophila melanogaster at the Gpdh + locus was determined by thermal stability studies of the protein. The results indicate a lack of variation using these methods both in and between the two common electrophoretic variants. It is suggested that α-GPDH is conserved in primary structure, which may be related to its critical role in flight muscle metabolism.
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  • 67
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    Biochemical genetics 16 (1978), S. 855-865 
    ISSN: 1573-4927
    Keywords: kynurenine hydroxylase ; cinnabar locus ; EMS mutagenesis ; Drosophila melanogaster
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract A study was undertaken to isolate mutations affecting the temporal appearance of kynurenine hydroxylase in Drosophila melanogaster. Such mutations, lacking or having reduced enzyme activity at the larval or pupal stage only, could represent changes in regulatory functions. Mutagenesis was carried out using EMS. Potential mutations were isolated from mass F1 cultures. The screening of large numbers of individuals was made possible by the use of the mutant red, which allowed visual classification for the presence or absence of the enzyme at both stages. From a series of six mutagenesis experiments 111,561 chromosomes were tested, and 122 phenotypically mutant F1 individuals were found. From these, 38 inheritable mutations were isolated which, by phenotypic observation, lacked or had reduced enzyme activity at the larval and pupal stages. Assay of enzyme activity levels in several of the mutants confirmed the phenotypic data. All of the 27 mutations that could be tested further are recessive and behave as cinnabar alleles. Complementation tests were performed between these 27 mutant stocks, and no complementation in the production of eye color has been seen between the mutants examined. When extended collection periods were used, a significantly higher percentage of inheritable mutations was isolated from the first 3 days of the screen. Over 80% of the F1 phenotypic mutants could be classified as mosaics, which indicates that cinnabar can be autonomous under certain conditions. The failure to isolate mutations in possible regulatory function is discussed.
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  • 68
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    Fresenius' Zeitschrift für analytische Chemie 293 (1978), S. 416-416 
    ISSN: 1618-2650
    Keywords: Best von Vitamin D2 ; Spektralphotometrie ; HCl, Tetrachloräthan
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    Topics: Chemistry and Pharmacology
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  • 69
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    Fresenius' Zeitschrift für analytische Chemie 293 (1978), S. 416-416 
    ISSN: 1618-2650
    Keywords: Best. von Pikrinsäure ; Spektralphotometrie ; Zink und Ammoniumchlorid
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  • 70
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    Fresenius' Zeitschrift für analytische Chemie 292 (1978), S. 43-44 
    ISSN: 1618-2650
    Keywords: Best. von Uran(VI) mit Arsenazo III ; Spektralphotometrie ; starksaure Lösung
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    Topics: Chemistry and Pharmacology
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  • 71
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    Fresenius' Zeitschrift für analytische Chemie 292 (1978), S. 46-47 
    ISSN: 1618-2650
    Keywords: Best. von Thallium(I), Dimethylthalliumverbindungen ; Spektralphotometrie
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  • 72
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    Fresenius' Zeitschrift für analytische Chemie 292 (1978), S. 233-235 
    ISSN: 1618-2650
    Keywords: Spektralphotometrie ; Ableitungen höherer Ordnung, Analogdifferenzierer, Derivativverfahren
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Es wird über eine neu entwickelte Analog-Recheneinheit berichtet, mit der man Ableitungen von Spektren und anderen Meßsignalen erstmalig bis zur 7. Ordnung on-line verwirklichen kann. Wie die Prüfungen ergaben, ist die optimale Auflösung in den meisten Fällen mit der 4. Ableitung erreicht. Dann sind nämlich alle Schultern und Wendepunkte der Kurven in bipolare Signale übergeführt. Eine Aufstellung der wichtigsten bisherigen Anwendungsgebiete wird gegeben.
    Notes: Summary This report deals with a newly developed analogue computing accessory by which derivations of spectra and other electric signals up to the seventh order were realized on-line. A thorough study of this apparatus showed that in most cases fine-resolving is reached by the fourth derivation. In this case, all shoulders and points of inflections are resolved to bipolar signals. A number of examples for applying derivative spectrophotometry of higher order (DSHO-method) is also given.
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    Fresenius' Zeitschrift für analytische Chemie 292 (1978), S. 400-402 
    ISSN: 1618-2650
    Keywords: Bestimmung von Meclozin, Pyridoxin in pharmazeutischen Produkten ; Spektralphotometrie ; Orthogonalfunktion
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Summary A rapid spectrophotometric method for the analysis of tablets containing the title compounds without preliminary separation is developed. Thus, pyridoxine is determined by measurement at λ max while the six-points quadratic orthogonal polynomial has been used to determine meclozine. The mean percentage recoveries (8 determinations) were found to be 101.71±0.64 and 99.77±0.62% (P=0.05) for meclozine and pyridoxine hydrochlorides, respectively. Neither the Vierordt's nor the absorbance ratio methods gave accurate results as the proposed method. The method was applied successfully to the analysis of market preparations.
    Notes: Zusammenfassung Es wurde ein Verfahren zur schnellen Bestimmung der beiden Verbindungen ohne Vortrennung ausgearbeitet. Pyridoxin wird durch Messung beim Absorptionsmaximum von 292 nm bestimmt, Meclozin wird mit Hilfe eines quadratischen Sechspunkte-Orthogonalpolynoms berechnet. Die Wiederfindungsrate (8 Bestimmungen) lag bei 101,71±0,64 bzw. 99,77±0,62% (P=0,05). Vergleichsbestimmungen nach der Methode von Vierordt und dem Verfahren der Extinktionsverhältnisse gaben weniger genaue Resultate. Die vorgeschlagene Methode wurde mit gutem Erfolg auf handelsübliche Präparate angewendet.
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  • 74
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    Fresenius' Zeitschrift für analytische Chemie 293 (1978), S. 220-221 
    ISSN: 1618-2650
    Keywords: Best. von Magnesium ; Spektralphotometrie ; Trimethin-Reagentien aus Aminochalkogenuracilen
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Bekanntlich werden Trimethinfarbstoffe, als Reagentien für die photometrische Magnesiumbestimmung, durch die Kondensation von Malonaldehyd und Barbitursäure bzw. ihren Derivaten hergestellt. Auf ähnliche Weise erhält man mit 4(6)-Amino(2)-chalkogeno-uracilen und Malonaldehyd die Ammoniumsalze der Trimethinfarbstoffe, die sich ohne weitere Aufarbeitung als Reagentien für die photometrische Bestimmung einsetzen lassen. Die Herstellung der Verbindungen wird beschrieben.
    Notes: Summary It is known that trimethine dyes used for the photometrie determination of magnesium ions can be prepared by the condensation of malonicaldehyde with barbituric acid or its derivatives; In a similar way it is possible to use 4(6)-amino-2-chalcogeno-uracils giving with malonicaldehyde ammonium salts of the trimethine dyes, which are suited for the photometric determination without further manipulations. The preparation is described.
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  • 75
    ISSN: 1618-2650
    Keywords: Best. von Nickel, Kobalt mit 2-Carboxy-2′-hydroxy-3′,5′-dimethylazobenzol-4-sulfonsäure ; Spektralphotometrie
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    Topics: Chemistry and Pharmacology
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    Fresenius' Zeitschrift für analytische Chemie 292 (1978), S. 302-303 
    ISSN: 1618-2650
    Keywords: Best. von Aldehyden, aromat. mit Barbitursäure ; Spektralphotometrie. Best. von Barbitursäure mit p-Dimethylaminobenzaldehyd ; Spektralphotometrie
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    Fresenius' Zeitschrift für analytische Chemie 292 (1978), S. 359-361 
    ISSN: 1618-2650
    Keywords: Best. von Uran in Wasser ; Spektralphotometrie ; Arsenazo, Fällg. mit Al-Phosphat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Zur schnellen und genauen Bestimmung von Uranspuren in natürlichen, auch salzhaltigen Wässern, wird Uran durch Spurenfällung mit Aluminiumphosphat abgetrennt. Durch Auflösen des mit Zinkpulver vermengten Niederschlages erfolgt Reduktion zu U(IV), das mit Arsenazo III bestimmt wird. Der Extinktionskoeffizient beträgt 97000 cm2/Mol.
    Notes: Summary For the precise and accurate determination of uranium in natural, even saline, waters, it is separated by coprecipitation with Al-phosphate. The precipitate is mixed with zinc powder, dissolved and thus reduced to U(IV), which is determined with Arsenazo III. The molar absorptivity is 97000 cm2/mol.
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  • 78
    ISSN: 1618-2650
    Keywords: Best. von Phosphat neben Silicium, Arsen, Germanium ; Spektralphotometrie ; Extraktion mit Benzophenon, Molybdatmethode
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Summary A new type of separation of phosphate ion, along with its spectrophotometric determination, was established by liquid-liquid extraction, where the yellow heteropoly acid formed by the reaction with ammonium molybdate in acid solution is quantitatively extracted into molten benzophenone at a temperature of about 60° C. When cooled down to room temperature, the benzophenone extract converts from the liquid state to the solid state. The resulting solidified extract is dissolved in methyl propionate, and the phosphate ion in the solvent is determined spectrophotometrically by the blue heteropoly acid method. Possible interference by Si, As and Ge is eliminated by the separation procedure.
    Notes: Zusammenfassung Bei dem beschriebenen Verfahren wird die mit Ammoniummolybdat in saurer Lösung gebildete gelbe Heteropolysäure bei 60° C in geschmolzenes Benzophenon extrahiert. Dieses wird durch Abkühlen verfestigt, in Methylpropionat gelöst und in dieser Lösung das Phosphat spektralphotometrisch als blaue Heteropolysäure bestimmt. Si, As und Ge, die ebenfalls mit Molybdat reagieren, werden durch die Extraktion abgetrennt.
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  • 79
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    Behavior genetics 8 (1978), S. 53-64 
    ISSN: 1573-3297
    Keywords: Drosophila melanogaster ; geotaxis ; chromosome analysis ; dominance effects
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Psychology
    Notes: Abstract Positive and negative geotactic maze behaviors were selected in strains of Drosophila melanogaster, for over 40 generations on 15-unit classification mazes. A chromosome substition analysis of these behaviors was undertaken to determine which of the three major chromosomes is most important in causing the differences in geotactic maze behavior between the divergent strains. By following the appropriate mating scheme, every possible homozygous chromosomal combination of the X, II, and III chromosomes from the geopositive and geonegative strain was produced. Heterozygous combinations were also produced to test for dominance and interchromosomal interactions. The results indicate that all three chromosomes are involved in geotactic behavior. The order of importance was II〉III〉X. Dominance effects were found in females for the X chromosome from the geopositive strain and for the III chromosome from the geonegative strain. No evidence for interchromosomal interactions was uncovered.
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  • 80
    ISSN: 1573-3297
    Keywords: minority mating advantage ; Drosophila melanogaster ; mating behavior ; male courtship cues ; habituation by female
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Psychology
    Notes: Abstract Alleles at the brown locus ofDrosophila melanogaster combined with homozygous scarlet provide a useful model to demonstrate minority advantage of males in mating. Heterozygotes with orange (O) eyes equal in numbers to homozygotes with red (R) eyes (10∶10 in both sexes) displayed no bias favoring either eye color, but each eye color was favored when males occurred in a minority ratio (2∶18). In direct observation of single females with equal numbers of males (3∶3) as controls,O males courted less and more slowly thanR males, but females mated with either type without bias. When unequal (4∶1), the minority males were successful at more than twice the frequency expected. Whether successful or not, the minority males did not change their level of courtship, and thus cannot be said to compensate for their frequency in any way. The time between first courtship and mating was less for the minority males than for the majority males. We discard the hypothesis that the minority male will be accepted immediately or ahead of a majority male, because the opposite tended to occur: that if a minority male courted first he was less likely to be successful than if he waited until the majority courted. Our results then are in conformity with the hypothesis that a female samples males and their courtship cues, thus becoming habituated to the majority of the first courting male, but she accepts a male with a cue different from that which she originally detected but avoided. That male is most often the minority.
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  • 81
    ISSN: 1573-3297
    Keywords: Drosophila melanogaster ; olfactory response ; genetics ; chemical odorants ; odor-specific variant
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    Topics: Biology , Psychology
    Notes: Abstract Homozygous second chromosome lines were extracted from a natural population ofDrosophila melanogaster and tested for their olfactory responses to ethyl acetate. The chromosome lines were highly heterogeneous for this behavior, and the variability was also specific to other esters and ketones such as ethyl propionate, 2-butanone, 2-pentanone, and 3-pentanone. The responses to these odorants negatively correlated with the response to another odorant, lactic acid. A large part of this odorant-specific variation seemed to be controlled by genes located on the right arm of the second chromosome.
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    Behavior genetics 8 (1978), S. 475-479 
    ISSN: 1573-3297
    Keywords: Drosophila melanogaster ; selective breeding ; digging ; pupation site
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    Topics: Biology , Psychology
    Notes: Abstract The genetics of the digging behavior ofDrosophila melanogaster larvae was studied through selective breeding. Selection for low digging activity was successful, but selection for high digging activity was not. Selection for low and high digging activity affected another behavior, namely the choice of a pupation site. Digging behavior appears to be under polygenic control.
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    Behavior genetics 8 (1978), S. 487-502 
    ISSN: 1573-3297
    Keywords: Drosophila melanogaster ; ebony mutant ; black mutant ; β-alanine ; mating behavior ; aggression ; phenocopy ; dark strains ; light strains ; territorialism ; arena behavior ; spatial isolation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Psychology
    Notes: Abstract Effects of β-alanine on mating behavior and aggression were studied inDrosophila melanogaster using the following competitive pairs: (1) homozygous black (b/b) flies, in which β-alanine synthesis is decreased, vs. alanine is blocked vs. wild-type (e +/e+) flies; (2) dark flies, in which β-alanine incorporation is reduced, owing mainly to chromosome 3, vs. light flies collected from the same population as were the dark flies; (3) homozygous black (b/b) flies, in which β-alanine synthesis is decreased, vs. β-alanine-injectedb/b flies, which are phenocopies of wild-type flies. The behavior of mixed-sex groups was studied in a large, illumination-graded observation chamber containing food and in small uniformly illuminated cells also containing food. The relative competitive mating abilities of these types were measured in both experimental conditions. Uninjected black flies, but not injected ones, showed weak and unsteady gait and weak wing extension. In ebony these abnormalities were more extreme. Dark flies did not show these abnormalities. Accelerated sexual maturation was indicated in males by early onset of courtship and enhanced territorial aggression and in females by earliness of mating. Such acceleration was observed in ebony and dark flies, compared with light flies, and among β-alanine-injectedb/b flies competing with uninjected black flies. Ebony males, although maturing earlier than wild-type males, were less successful than wild-type males in mating. This difference was even greater when the flies were all allowed to mature before competing. Ebony females outmated wild-type females. Dark flies outmated light flies, and β-alanine-injectedb/b males outmated uninjected black males, especially in bright light. Ebony flies mated much longer than wild-type flies, and black flies mated slightly longer than injectedb/b flies. There was some spatial isolation of ebony from wild type, dark from light, and β-alanine-injected from uninjectedb/b flies in the illumination-graded observation chamber. Ebony flies more than wild type concentrated near food. Flies were attracted to the current of moist inlet air. They were also attracted to deposited excrement, and males defended such deposits as a mating area, thus showing rudiments of arena behavior in which a mating area away from the oviposition site is defended. Usually, however, the defended area focused on food.
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    Fresenius' Zeitschrift für analytische Chemie 293 (1978), S. 115-117 
    ISSN: 1618-2650
    Keywords: Best. von Palladium(II) mit Formazanen ; Spektralphotometrie
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    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Die o-Cl-substituierten Formazane-I und -II werden erstmalig dargestellt und ihre Eignung als photometrische Reagentien für Palladium überprüft. Formazan-I reagiert nur im Dioxan-WasserGemisch bei pH 3,5 zu einem grünen 1∶2-Pd-Komplex, während Formazan-II einen wasserlöslichen Komplex bildet, mit maximaler Absorption bei pH 3 (λmax= 633 nm, ɛ623=11.5·1031 Mol−1 cm−1 Das Beersche Gesetz ist im Bereich von 0,02–11 μg Pd/ml erfüllt.
    Notes: Summary The o-Cl substituted formazans I und II where newly synthesized and their application to the spectrophotometric determination of palladium has been evaluated. Formazan I reacts only in dioxanwater medium at pH 3.5 resulting in a green 1∶2 Pd-complex, whereas formazan II forms a water-soluble complex with maximum absorption at pH 3 (λmax= 633 nm, ɛ623=11.5×1031 Mol−1 cm−1). This system obeys Beer's law from 0.02–11 μg Pd/ml.
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    Fresenius' Zeitschrift für analytische Chemie 292 (1978), S. 29-33 
    ISSN: 1618-2650
    Keywords: Best. von Carbamaten, N-monosubstitutierte ; Spektralphotometrie ; Fearon-Reaktion
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung N-Monosubstituierte Carbamate werden mit 1,3-Diaminopropan in Gegenwart geringer Mengen Natriumhydroxid zu einem Harnstoffderivat umgesetzt, das seinerseits mit Hilfe der „Carbamid-Reaktion“ nach Fearon bestimmt wird. Die Erfassungsgrenze liegt für N-Methylcarbamate im Bereich von 20 nmol. Im Falle der N-Methylcarbamate ließ sich das Harnstoff-Zwischenprodukt als N-Methyl-N′-(3-aminopropyl)-harnstoff identifizieren; diese Substanz entsteht bei der Amidierung in nahezu quantitativer Ausbeute.
    Notes: Summary N-Monosubstituted carbamates are converted to urea derivates by reaction with 1,3-diaminopropane in the presence of small amounts of sodium hydroxide. The urea derivatives are determined by Fearon's “carbamide reaction”. The detection limit for N-methylcarbamates is in the range of 20 nmoles. In the case of N-methylcarbamates, N-methyl-N′-(3-aminopropyl)-urea was found to be the intermediate urea derivative, which is formed in nearly quantitative yield.
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    Fresenius' Zeitschrift für analytische Chemie 292 (1978), S. 299-299 
    ISSN: 1618-2650
    Keywords: Best. von Titan ; Spektralphotometrie ; Salicylsäure als Reagens
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
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    Fresenius' Zeitschrift für analytische Chemie 289 (1978), S. 282-284 
    ISSN: 1618-2650
    Keywords: Best. von Aromat. Aldehyden mit Diphenylamin ; Spektralphotometrie ; allg. Verfahren
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Summary Aromatic aldehydes and some of their binary mixtures can be determined spectrophotometrically with diphenylamine in the presence of hydrochloric acid. Errors are in the range of 6–10%. Various other organic compounds do not interfere.
    Notes: Zusammenfassung Aromatische Aldehyde und einige ihrer binären Gemische können mit Diphenylamin in salzsaurer Lösung spektralphotometrisch bestimmt werden. Fehler sind im Bereich von 6–10%. Eine große Zahl anderer organischer Verbindungen stört nicht.
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    Fresenius' Zeitschrift für analytische Chemie 289 (1978), S. 285-285 
    ISSN: 1618-2650
    Keywords: Best. von Ameisensäurederivaten ; Spektralphotometrie ; Decarbonylierung
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
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    Fresenius' Zeitschrift für analytische Chemie 290 (1978), S. 47-47 
    ISSN: 1618-2650
    Keywords: Best. von Wolfram ; Spektralphotometrie ; SalicylsÄure als Reagens
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
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    Fresenius' Zeitschrift für analytische Chemie 290 (1978), S. 104-105 
    ISSN: 1618-2650
    Keywords: Best. von Kallikrein in Plasma ; Spektralphotometrie ; chromogenes Peptidsubstrat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
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    Fresenius' Zeitschrift für analytische Chemie 290 (1978), S. 116-117 
    ISSN: 1618-2650
    Keywords: Best. von Säure-Base-Gleichgewichten ; Spektralphotometrie ; Mehrwellenlängen
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    Fresenius' Zeitschrift für analytische Chemie 290 (1978), S. 117-118 
    ISSN: 1618-2650
    Keywords: Spektralphotometrie ; Spektrometrische Titration ; Molekülstruktur ; Lösung
    Source: Springer Online Journal Archives 1860-2000
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    Fresenius' Zeitschrift für analytische Chemie 290 (1978), S. 118-119 
    ISSN: 1618-2650
    Keywords: Kinetische Analyse ; Spektralphotometrie ; Mehrwellenlängen ; Stopped-flow
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    Fresenius' Zeitschrift für analytische Chemie 290 (1978), S. 126-127 
    ISSN: 1618-2650
    Keywords: Spektralphotometrie ; Zentrifugalanalysator, Küvetten längs zum Lichtstrahl
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  • 95
    ISSN: 1618-2650
    Keywords: Best. von Proteolytischen Enzymen, Arylamidasen in Liquor ; Spektralphotometrie
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    Fresenius' Zeitschrift für analytische Chemie 290 (1978), S. 174-175 
    ISSN: 1618-2650
    Keywords: Best. von Lipase in Serum ; Spektralphotometrie ; Zentrifugalanalysator
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    Fresenius' Zeitschrift für analytische Chemie 290 (1978), S. 179-180 
    ISSN: 1618-2650
    Keywords: Best. von D-Xylose ; Spektralphotometrie ; Xylose-NADP-oxidoreductase
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
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    Fresenius' Zeitschrift für analytische Chemie 293 (1978), S. 286-289 
    ISSN: 1618-2650
    Keywords: Best. von Fluorid mit Thoriumnitrat ; Spektralphotometrie ; Alizarin S als Indicator, automatisch
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Für Fluoridgehalte zwischen 1 und 20 mg in 85 ml Lösung wurde die photometrische Titration mit Thoriumnitrat und Alizarin S automatisiert und die Arbeitsbedingungen optimiert. Ausgewählte Matrixeinflüsse werden eingehender untersucht. Dieses Verfahren ist besonders für die Bestimmung von Fluorid aus Peroxid-Aufschlüssen geeignet.
    Notes: Summary The photometric titration of fluoride with thorium nitrate and Alizarin S as indicator has been automated and optimized for fluoride levels between 1 and 20 mg/85 ml solution. The interference of several ions has been investigated. This procedure is particularly useful for the determination of fluoride after fusion with peroxides as fluxing agents.
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    Fresenius' Zeitschrift für analytische Chemie 293 (1978), S. 411-412 
    ISSN: 1618-2650
    Keywords: Best. von Aminen, aliphat, primär ; Spektralphotometrie ; o-Phthaldialdehyd und Mercaptoäthanol
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
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    Fresenius' Zeitschrift für analytische Chemie 292 (1978), S. 293-295 
    ISSN: 1618-2650
    Keywords: Best. von Chlorid in Mineralien, Gesteinen ; Spektralphotometrie ; Pyrohydrolyse
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Summary This simple method for the determination of chloride takes a total time of 15 min. Samples are mixed with silica in the ratio 1∶1, and the chloride is liberated in an induction furnace by pyrohydrolysis within ca. 10 min. The chloride is collected in a 0.020 M sodium-hydroxide solution. This solution is filled up to 200 ml with twice distilled water and absorption is measured with ferric ammonium sulphate and mercury(II) thiocyanate solution by a Zeiss Elko II photometer. Analysis of three international reference samples show excellent accuracy with a standard deviation of less than 4% (e.g. for a chloride content of 117 ppm in Andesite AGV-1).
    Notes: Zusammenfassung Diese einfache Methode zur Bestimmung des Chloridions benötigt eine Gesamtzeit von 15 min. Die Proben wurden mit Kieselsäure im Verhältnis 1∶1 vermischt und in einem Induktionsofen 10 min lang pyrohydrolysiert. Das entstandene HCl wurde in einer 0,020 M Nariumhydroxidlösung aufgefangen. Diese Lösung wurde mit zweifach dest. Wasser auf 200 ml aufgefüllt, mit Eisenammoniumsulfat- und Quecksilberthiocyanatlösung versetzt und deren Absorption mit einem Zeiss-Elko II-Photometer gemessen. Die Analysen von 3 internationalen Referenzproben zeigen eine hohe Präzision mit einer relativen Standardabweichung von weniger als 4% (z. B. für einen Gehalt von 117 ppm Chlor in Andesit AGV-1).
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