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181.
Summary A fragile site at the long arms (q21) of chromosome 16 was found in two persons, each of whom became the parent of a child with a de novo structural chromosome abnormality—a balanced autosomal translocation and an autosomal deletion. The question of an increased risk of structural chromosome abnormalities in the offspring of persons with fragile site long arm 16 is discussed. 相似文献
182.
Jens Kvist Nielsen 《Entomologia Experimentalis et Applicata》1978,24(1):41-54
Feeding responses of four Chrysomelidae to six less acceptable plants and to compounds from them were investigated by means of leaf disc tests. Significant differences were found between responses of different species, and plants containing potent feeding inhibitors were always rejected. Cucurbitacins are potent feeding inhibitors to Phyllotreta nemorum, and this species does not eat Iberis species containing these compounds. Cardenolides are potent feeding inhibitors to P. undulata, P. tetrastigma and Phaedon cochleariae, and these three species do not eat the cardenolide containing Cheiranthus and Erysimum.Six different glucosinolates all proved to be stimulatory when applied to pea leaf discs. Although the glucosinolates differed somewhat in their ability to stimulate feeding, no correlation is found between content of glucosinolates and acceptability of the investigated plants. Application of sinigrin to Iberis and Cheiranthus did not improve their acceptability. The presence of glucosinolates is necessary for feeding to occur, but it is less important which glucosinolates are present.Cardenolides and cucurbitacins are suggested to be a second generation of protective compounds in Cruciferae, glucosinolates being the first.
The Danish Natural Science Research Council supported the research. 相似文献
Zusammenfassung Der Einfluss einiger sekundärer Pflanzenstoffe aus Cruciferen auf die Futteraufnahme von vier Chrysomeliden, die auf dieser Pflanzenfamilie vorkommen, wurde mittels Blattscheiben-Tests untersucht. Cucurbitacine sind starke Frasshemmstoffe für Phyllotreta nemorum, weniger starke Hemmstoffe für P. undulata und schwache Hemmstoffe für P. tetrastigma und Phaedon cochleariae. Iberis-Arten, die Cucurbitacine enthalten, werden von P. nemorum und P. undulata abgelehnt, von den beiden anderen Arten aber akzeptiert. Cardenolid-Glykoside vom Strophanthidin-Typ sind starke Frasshemmstoffe für P. undulata, P. tetrastigma und Phaedon cochleariae. Diese Arten lehnen Cheiranthus-und Erysimum-Arten, die solche Stoffe enthalten, ab. Die Futteraufnahme von P. nemorum wird von diesen Stoffen nicht beeinflusst; P. nemorum akzeptiert Cheiranthus- und Erysimum-Arten.Futteraufnahme fand bei Abwesenheit von Senfölglukosiden nicht statt. Sechs verschiedene Senfölglukoside waren alle imstande, das Aufnehmen von Erbsen-Blattscheiben zu stimulieren. Gewisse Unterschiede in der stimulierenden Wirkung der einzelnen Glukoside wurden gefunden. Das Vorkommen bestimmter Glukoside und die Akzeptabilität der Pflanzen zeigten aber keine Korrelation. Anwesenheit oder Abwesenheit von Frasshemmstoffen beeinflusst die Akzeptabilität der Pflanzenarten mehr als die Anwesenheit bestimmter Senfölglukoside.Wenn Senfölglukoside als eine erste Generation von Abwehrstoffen in Cruciferen aufgefasst werden, können Cucurbitacine in Iberis und Cardenolid-Glykoside in Cheiranthus und Erysimum als eine zweite betrachtet werden.
The Danish Natural Science Research Council supported the research. 相似文献
183.
Renewed examinatinon with improved banding techniques of a boy previously reported to have the karyotype 46, XY,del(12)(p11) revealed a translocation 46, XY,t(10;12)(p13;p11), and reexamination of a boy previously reported to have the karyotype 46,XY/46,XY,del(5)(p13) showed the same mosaicism, but with a significantly lower frequency of cells with del(5)(p13), 8% compared with 23% at the time of birth. The decrease of the frequency of cells with chromosome abnormality in mixoploids during the first years of life as found in the present case as well as in prevously reported cases is discussed. 相似文献
184.
ESTIMATION OF NORADRENALINE AND ITS MAJOR METABOLITES SYNTHESIZED FROM [3 H]TYROSINE IN THE RAT BRAIN
M Nielsen 《Journal of neurochemistry》1976,27(2):493-500
Abstract— A new procedure is described for the estimation of [3H]noradrenaline (NA) and its major metabolites free and conjugated 3-methoxy-4-hydroxyphenylglycol (MOPEG) and free and conjugated 3,4-dihydroxyphenylglycol (DOPEGI in the rat brain. The procedure involves adsorption on to alumina, cation exchange chromatography. enzymatic hydrolysis of conjugates and thin-layer-chromatography after intraventricular (IVT) or intravenous injection of [3H]tyrosine. In a time-course study the formation and accumulation of the metabolites have been measured from 15min to 23h after IVT injection of [3H]tyrosine. [3H]MOPEG and [3H]DOPEG were found in almost equal amounts during the synthesis phase of [3H]NA as well as during the storage and disappearance phase of [3H]NA. The maximum levels of conjugated [3H]MOPEG and conjugated [3H]DOPEG were found 2 h after IVT [3H]tyrosine. At this time interval the levels of free [3H]MOPEG and free [3H]DOPEG amounted to 25% and 11%, respectively of the corresponding conjugates. Increasing doses of IVT injected [3H]tyrosine (10-90 °Ci) revealed that the accumulation of [3H]NA and metabolites was linear up to about 50 °Ci. Following intravenous instead of IVT injection of [3H]tyrosine. much higher doses (325 °Ci) were needed to obtain measurable amounts of total [3H]MOPEG and [3H]DOPEG-SO4 in the rat brain. The formation of labelled NA metabolites from [3H]NA in the rat brain in vim measured as total [3H]MOPEG and [3H]DOPEG-SO4 was influenced by drugs affecting [3H]NA synthesis, release and metabolism. Synthesis inhibition with a-methyltyrosine (250mg-kg?1) or FLA-63 (30mg-kg?1) and inhibition of monoamine oxidase with pargyline (75mg-kg?1) or clorgyline (2mg-kg?1) strongly decreased the accumulation of total [3H]MOPEG and [3H]DOPEG-SO4. Noradrenaline receptor blockade with phenoxybenzamine (20mg-kg?1) increased both total [3H]MOPEG and [3H]DOPEG-SO4 to about 160% of the control values. NA release and uptake inhibition induced by d-amphetamine (10mg-k?1) or phenylethylamine (two doses of 80mg-kg?1) decrease strongly the levels of [3H]NA and [3H]DOPEG-SO4. whereas total [3H]MOPEG was only very slightly decreased or even increased as compared to controls. 相似文献
185.
Summary A family with autosomal reciprocal translocation t(4;13) (q25;q31) with a sibship comprising 2 children with unbalanced karyotypes, der(13) partial trisomy 4q, 1 child with the balanced translocation, and 2 abortions were studied. The segregation risk of unbalanced derivation in reciprocal translocations is discussed. The clinical picture of the 2 children with partial trisomy 4q is compared with similar cases. 相似文献
186.
Summary The incidence of Edwards' syndrome was found to be 1 per 4857 newborn children of 34000 consecutively newborn children in two Danish counties. Six of the 7 cases were born during the months of February through April.The incidence was high compared with the expected incidence of Edwards' syndrome of approximately 1 per 10000. This might be due to clustering in the area studied during the period 1967 to 1973.The finding of variations in incidence of children with Edwards' syndrome in different parts of the world, as well as the finding of seasonal variation in birth of such children, indicates that some of the etiological factors of nondisjunction of chromosome 18 are of an environmental nature. 相似文献
187.
Johannes Nielsen 《Human genetics》1975,26(3):215-222
Summary The purpose of making chromosome investigations of newborn children as well as ethical problems in such studies and in follow-up studies of children with chromosome abnormalities is discussed, and a survey of 6 chromosome studies from a total of 47145 newborn children is presented.It is stressed that more chromosome studies of newborn children are needed for several reasons, but one of the main reasons is to study the development of children with different chromosome abnormalities, especially those with sex-chromosome abnormalities and compare them with controls. 相似文献
188.
Johannes Nielsen 《Human genetics》1975,29(2):155-159
189.
Nils Milman Niels Graudal Lillian Staub Nielsen Bjørn Mathiassen Palle Tauris Birgit Lund Jørgen Schøler Kristensen Kirsten Fenger 《Human genetics》1990,85(2):228-232
Summary Pedigree studies were performed based on one Faroese and four Danish probands with overt idiopathic hemochromatosis (IH). The study consisted of HLA typing and determination of biochemical iron status indicators (serum transferrin saturation, serum ferritin). In total, 130 persons were evaluated. The screening identified 6 homozygous (h/h) subjects with preclinical IH, 46 heterozygous (h/n), and 8 normal (n/n) subjects, while 39 subjects were classified as normal or heterozygous (n/h?). One family demonstrated both a homozygous x heterozygous as well as a heterozygous x heterozygous mating. Recombination between the HLA region and IH locus occurred possibly in three subjects in three different families. The significance of detailed screening in families with probands with IH is discussed. 相似文献
190.
Purification and properties of yeast glycogen phosphorylase a and b 总被引:10,自引:0,他引:10