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71.
K. K. Wu D. J. Heinz H. K. Meyer S. L. Ladd 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1980,56(6):241-244
Summary Five Hawaiian commercial sugarcane (Saccharum sp. hybrids) clones were crossed in a full diallel. Four morphological characters were studied in the progeny: number of millable stalks per plant, stalk diameter, stalk length, and sucrose content. A fifth character, plant volume, was calculated from stalk number, stalk diameter and stalk length. The five selected parental clones were treated as fixed variables in the analysis. General combining ability (gca) was significant for all five characters; specific combining ability (sca) was significant for stalk diameter, stalk length, and plant volume. The variance for gca was large in all progeny populations. However, the variance for sca was large in the progeny of only some clones and/or for some individual characters. Parents were evaluated on the basis of their general combining ability: clone H49-3533 had high gca for sucrose content, while clone H53-5356 had high gca for plant vigor.Published with the approval of the Director as Journal Series Paper No. 455, Experiment Station, Hawaiian Sugar Planters' Association. 相似文献
72.
Rainer Renkawitz Susan A. Gerbi Karl Heinz Glätzer 《Molecular & general genetics : MGG》1979,173(1):1-13
Summary In this report we show by hybridization of restriction fragments and by Miller spreads that the unit repeat of the fly Sciara coprophila is only 8.4 kb which is the smallest known for a multicellular eukaryote. The 8.4 kb EcoR1 fragment containing a complete unit of Sciara rDNA was cloned in pBR322, and mapped by the method of Parker (1977) and also by double digestion. The coding regions for 28S, 18S, and 5.8S RNA were localized by the method of Berk and Sharp (1977). From these data we conclude that the nontranscribed spacer, external transcribed spacer, and internal transcribed spacer are all shorter than in other organisms, thereby giving rise to the shorter overall rDNA repeat unit of Sciara.At least 90% of the Sciara rDNA repeats are homogeneous, with a length of 8.4 kb, but a 700 bp ladder of minor bands can also be found in digestions of total genome DNA. This profile of major and minor bands is identical between the X and X chromosomes, as seen by a comparison of several genotypes.There are only 45 rRNA genes per X chromosome of Sciara (Gerbi and Crouse, 1976). These can easily be counted by low magnification Miller speads which show that virtually all gene copies are actively being transcribed in the stage of spermatogenesis examined. This is the first demonstration for any reiterated gene family where all copies are shown to be simultaneously active.Present address same as last author 相似文献
73.
A severe and a mild potato spindle tuber viroid isolate differ in three nucleotide exchanges only 总被引:5,自引:0,他引:5
Hans J. Gross Ursula Liebl Heidemarie Alberty Guido Krupp Horst Domdey Karla Ramm Heinz L. Sänger 《Bioscience reports》1981,1(3):235-241
Fingerprint analyses of two potato spindle tuber viroid (PSTV) isolates causing severe and mild symptoms~ respectively, in tomato exhibited defined differences in the RNase T1 and RNase A fingerprints. The complete sequencing of the mild isolate and the comparison of its primary structure with the previously established one of the pathogenic type strain revealed that oligonucleotides CAAAAAAG, CUUUUUCUCUAUCUUACUUG, and AAAAAAGGAC in the severe strain are replaced by CAAUAAG, CUUUUUCUCUAUCUUUCUUUG, AAU, and AAGGAC in the 'mild' strain. Thus, three nucleotide exchanges at different sites of the molecule may change a pathogenic viroid to a practically non-pathogenic isolate. The possible correlation between the secondary structure in a defined region of the PSTV molecule and its pathogenicity for tomato is discussed. 相似文献
74.
Summary In the American cockroach, the distribution and connections of neuronal elements of the terminal ganglion-proctodeal nerve-hindgut system were investigated by means of immunohistochemical methods and axonal CoCl2 iontophoresis. Proctolinlike immunoreactivity was localized within neurons of the terminal ganglion projecting into the proctodeal nerve on the one hand, and in nerve cells without a direct connection to this system on the other. Immunohistochemically, in whole mount preparations fibres of the proctodeal nerve and terminal structures in the hindgut musculature exhibit strong proctolinlike immunoreactivity. At the light- and electron-microscopic levels the pathways of about 30 somata of the proctodeal neural system were characterized by cobalt chloride iontophoresis. The relationships of cobalt filled and immunoreactive neuronal structures are discussed.For the preparation of tritiated proctolin we thank Dr. S. Reißmann, WB Biochemie, Sektion Biologie, FSU JenaThe authors wish to thank G. Schörlitz, Film- und Bildstelle, FSU Jena, for photographs of whole mount preparations and Ms. A. Zinßer and Mrs. B. Cosack for excellent technical assistance. 相似文献
75.
Bart Marescau Armand Lowenthal Eddy Esmans Yves Luyten Frank Alderweiereldt Heinz Georg Terheggen 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1981,224(2):185-195
Liquid column chromatographic studies of monosubstituted guanidino compounds, which are excreted in the urine of patients with hyperargininaemia are reported. The guanidino-positive peaks, with the highest excretion values, were isolated from urine and the isolated compounds were identified by thin-layer chromatography and gas chromatography—mass spectrometry. Guanidinoacetic acid, N-α-acetylarginine, argininic acid, γ-guanidinobutyric acid, arginine and α-keto-δ-guanidinovaleric acid were found to be excreted at high levels in the urine of patients with hyperargininaemia compared with controls. 相似文献
76.
K. K. Wu D. J. Heinz H. K. Meyer S. L. Ladd 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1977,51(1):29-33
Summary An approximate method to determine sample size for the estimation of population variance, 2, is given. The estimate of 2 is denoted as s2 . Based on the assumption of a normal distribution for (s2/2–1), the sample size is approximately equal to 20,000 z2
p,/k2; where z is a standard normal deviate, p is the probability that s2 ( 100¦s2 – 2¦/2) is less than, or equal to, a critical value k, and k (measured as gDs2) is the desired precision of s2 .The expected value of s2, with respect to sample size, and the expected cumulative frequencies of s2 over sample size for various k values are given. Their goodness of fit to the observed results was satisfactory except for populations that were different from normal. The observed values were taken from a study on four yield components in five sugarcane polycross progenies, grown in two contrasting environments over 2 years in three selection stages.The expected s2 was found to be independent of the population coefficient of variance.Research suppoted in part by USDA, ARS, grant #12-14-5001-34. Published with the approval of the Director as Paper No. 412 in the Journal Series of the Experiment Station, Hawaiian Sugar Planters' Association. 相似文献
77.
78.
Heinz Egge Jean Claude Michalski Gerard Strecker 《Archives of biochemistry and biophysics》1982,213(1):318-326
Three oligosaccharides isolated from the urine of a patient suffering from mannosidosis, a Man9GlcNAc, a Man8GlcNAc, and a Man7GlcNAc, were analyzed by electron impact mass spectrometry at 20 eV after reduction with NaB2H4 and permethylation. Molecular ions were observed at 2144, 1940, and 1736, respectively. In the high-mass range very intense ions were found at M-45. The mass spectrum of the homogenous decasaccharide Man9GlcNAc1D contains ions that could be attributed to specific parts of each of the three antennae of the molecule. Thus characteristic key ions were recognized. With the aid of these key ions the spectra of the nona- and octasaccharide mixtures could be evaluated in a qualitative and a semiquantitative way. In the nonasaccharide all three possible isomers that can be produced by cleavage of one of the three terminal α-mannoses are present, although in differing amounts. However, only five of the six possible isomers of the octasaccharide could be detected. 相似文献
79.
Noemi Luknar-Gabor Ursula Fenger Christoph Wagener Heinz Breuer 《Biochemical and biophysical research communications》1982,109(4):1270-1275
A variant of the carcinoembryonic antigen (CEA) with lower molecular weight than a CEA reference preparation has been separated from CEA. Using a polyclonal, spleen absorbed anti-CEA antiserum, the variant crossreacts with reference CEA in immunodiffusion. The CEA-activity of the variant has been demonstrated using an enzyme-immunoassay with monoclonal CEA specific antibodies. There is sufficient immunological evidence that this variant is a distinct antigen different from the crossreactive antigens described so far. The reactivity of the polyclonal anti-CEA antiserum with the CEA variant was abolished by absorption against the immobilized variant. 相似文献
80.
Heinz Düttmann 《Journal of Ornithology》1992,133(4):365-380
Zusammenfassung Brandentenküken verfügen über drei verschiedene Taucharten, die sich nach Ausführung und Tauchdauer deutlich unterscheiden lassen. Während das Nahrungstauchen in der 6. Lebenswoche eingestellt wird, bleiben Tauchbaden und Fluchttauchen lebenslang erhalten. Neben dem Nahrungstauchen werden weitere Techniken des Nahrungserwerbs in Abhängigkeit vom Nahrungsangebot und dem Entwicklungsstand unterschiedlich häufig angewendet. Der zeitliche Aufwand für die Nahrungsaufnahme ist in den ersten 2 Lebenswochen maximal. Anschließend nimmt er, bei schneller als bei kontinuierlich ab. Kälteperioden führen zu einer weiteren Reduzierung. Die Schlafhäufigkeit sinkt nach einer anfänglichen Zunahme (bis 10. Lebenswoche) ab. Kälteperioden bewirken eine Zunahme. Unter 3 verschiedenen Schlafhaltungen wird bis zur 12. Lebenswoche das Schlafen im Liegen bevorzugt. Danach nimmt es zugunsten des einbeinigen Schlafens im Stehen, das erstmals in der 7. Lebenswoche auftritt, ab. Kälteperioden stellen die ursprünglichen Häufigkeitsverhältnisse zwischen beiden Schlafhaltungen wieder her. Brandentenküken bilden in den ersten Lebenswochen Schlafhaufen. Ihre Häufigkeit sinkt bis zur 12. Lebenswoche kontinuierlich auf Null ab.
Ontogenetic changes in sleeping, diving and foraging behaviour in Shelduck (Tadorna tadorna) ducklings
Summary Shelduck ducklings show different types of diving behaviour: diving for food, flight-diving and dashing and diving in comfort situations. These types differ by diving duration and the behaviour of the ducks. In diving for food diving duration and frequency decrease during the first 6 weeks. After this, no food diving was observed. Other feeding methods include sieving, upending, pecking on the surface of water, feeding on plants and foot-trampling. Except for feeding on plants, which was first observed in the 10th week, all feeding methods are present in one day old ducklings. The share of foraging time is highest during the first 2 weeks of life. Afterwards it decreases (in females faster than in males) from about 50 to 20 %. During cold weather, it was still lower whereas resting and sleeping behaviour increased. After an increase during the first 10 weeks of life, the share of resting decreases to 25–40 % of observation time. Shelduck ducklings have 3 different sleeping postures: lying, standing on one leg, standing on two legs. During the first weeks of life ducklings only sleep standing on two legs or lying on the ground, the latter is being clearly preferred. Standing on one leg appeared in the 7th week. Its frequency increased and it became the most prominent resting pattern. Only during cold spells shelducks do return to sleep by lying on the ground. Under such conditions also sleeping in contact with one another reoccurs, which is typical for ducklings during their first weeks of life.相似文献