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41.
Karien E. De Rooij Pia A. M. De Koning Gans Raymund A. C. Roos Gert-Jan B. Van Ommen Johan T. Den Dunnen 《Human genetics》1995,95(3):270-274
The mutation causing Huntington disease (HD) has been identified as an expansion of a polymorphic (CAG)
n
repeat in the 5 part of the huntingtin gene. The specific neuropathology of HD, viz. selective neuronal loss in the caudate nucleus and putamen, cannot be explained by the widespread expression of the gene. Since somatic expansion is observed in affected tissue in myotonic dystrophy, we have studied the length of the (CAG)
n
repeat in various regions of the brain. Although we have not found clear differences when comparing severely and mildly affected regions, we have observed a minor increase in repeat length upon comparison of affected brain samples with cerebellum or peripheral blood. Hence, although further somatic amplification seems to occur in affected areas of the brain, the differences between affected and unaffected regions are too small to make this mechanism an obvious candidate for the cause of differential neuronal degeneration in HD. 相似文献
42.
Therapy of bovine ocular squamous-cell carcinoma with local doses of interleukin-2: 67% complete regressions after 20 months of follow-up 总被引:1,自引:1,他引:0
F. W. Willem Den Otter Graham Hill Wim R. Klein Jan Willem Koten Peter A. Steerenberg Pieter H. M. De Mulder Christopher Rhode Rachel Stewart Joop A. J. Faber E. Joost Ruitenberg Victor P. M. G. Rutten 《Cancer immunology, immunotherapy : CII》1995,41(1):10-14
We have tested the therapeutic potency of peritumorally injected low doses of interleukin-2(IL-2). Seventy tumours of the bovine ocular squamous-cell carcinoma (BOSCC), 1–3 cm in diameter, were treated with 5000, 20 000 or 200 000 U IL-2 from Eurocetus (Chiron) to find the optimal dose for treatment. Injections were given peritumorally on Monday to Friday on 2 consecutive weeks. The size of the tumours was measured before treatment and 1, 3, 4, 9 and 20 months after treatment. After 9 months complete regression was observed in 89% of the tumours treated with 5000 U IL-2, 80% treated with 20 000 U and 67% treated with 200 000 U. After 20 months, there was complete regression of 35%, 31% and 67% of the tumours respectively. The 9-and 20-month results of the 200 000-U treatment are significantly better than those of the 5000-U and 20 000-U treatments taken together. This protocol may be useful to treat advanced inoperable tumours (e.g. of the nasopharynx or skin) of human patients. 相似文献
43.
44.
M. F. Claridge J. Den Hollander D. Haslam 《Entomologia Experimentalis et Applicata》1984,36(2):107-114
A morphometric analysis of biotypes 1, 2 and 3 from the International Rice Research Institute, Philippines, reared respectively on rice cultivars TN1, Mudgo and ASD7, showed significant differences, but some overlap between them. When the three biotypes were each reared for a single generation on TN1, morphometric differences were very greatly reduced and the distributions widely overlapped.Biotypes 2 and 3 were significantly less fecund than biotype 1 when reared on their normal host varieties. When all were reared on TN1, biotype 3 showed a somewhat lower fecundity than did 1 and 2, but the difference was less than previously reported.It is concluded that the evidence for the association of morphometric differences with virulence characteristics inN. lugens is not proved. Equally there is no evidence that morphometric data may be used to identify field populations with distinct patterns of virulence.
La signification des différences morphométriques et de fécondité entre des biotypes deNilaparvata lugens
Résumé Ce que l'on a appelé des biotypes deN. lugens sont des populations caractérisées par différents types de virulence à l'égard de différents cultivars résistants de riz, mis en évidence par des essais variétaux systématiques. Différents chercheurs ont tenté de trouver des caractères morphologiques pour identifier ces biotypes.Nous avons fait une analyse morphométrique des biotypes 1, 2 et 3 de l'International Rice Research Institute (IRRI) Philippines. Quand ils sont élevés sur leur propre varieté — biotype 1 sur TN1, 2 sur Mudgo, 3 sur ASD7 — des différences significatives sont observées, bien qu'il y ait un chevauchement considérable. Quand les 3 populations biotypes sont élevées sur la variété sensible TN1, les différences morphométriques sont réduites et le chevauchement fortement augmenté. Nous pourrions alors conclure qu'une part importante de la différenciation morphométrique est due à des facteurs écologiques et non à des différences génétiques entre les populations. Des chercheurs avaient indiqué des différences de fécondité entre les biotypes de l'IRRI, le biotype 3 étant significativement moins fécond; les résultats publiés son contradictoires. Nos observations suggèrent une certaine diminution de la fécondité pour le biotype 3 élevé sur TN1, mais plus limitée que les autres auteurs ne l'avaient envisagée.Nous en concluons qu'il n'y a pas de véritable preuve pour étayer l'hypothèse que les biotypes deN. lugens sont caractérisés par des paramètres morphométriques génétiquement déterminés. Il est alors fallacieux de suggérer que de tels caractères pourraient être utilisés pour identifier des populations avec différents types de virulence. Nous repoussons aussi l'hypothèse que les biotypes représentent une étape dans le processus de spéciation.相似文献
45.
46.
S. Takagi H. Sakata T. Yoshida K. Den T.K. Fujii H. Amemiya M. Tomita 《Prostaglandins & other lipid mediators》1978,15(5)
ONO-802 was used in the form of vaginal suppositories for the termination of early pregnancy in 63 healthy volunteers. Fifty-four (86%) of the 63 cases had complete abortions and remaining 9 (14%) had incomplete abortions.One (1.6%) of the 63 cases complained of nausea and vomiting, and 3 (4.8%) complained of headaches. No other side effects were observed.These results suggest that ONO-802 is acceptable in the form of vaginal suppositories for the termination of early pregnancy. 相似文献
47.
Single bilayer vesicles were prepared by sonication of 5 mol% 1-palmitoyl lysophosphatidylcholine and 95 mol% egg phosphatidylcholine. Incubation with lysophospholipase results in a fast hydrolysis of 80–90% of lysophosphatidylcholine. The remaining lysophosphatidylcholine is only very slowly hydrolysed. There results are interpreted as lysophosphatidylcholine being asymmetrically distributed over the two halves of the bilayer. The slow phase of lysophosphatidylcholine hydrolysis sets an upper limit to the rate of transbilayer movement of lysophosphatidylcholine. The half time of this process at 37° C is estimated to be about 100 h. Incorporation of cholesterol in the vesicles reduces the distributional asymmetry of lysophosphatidylcholine to the extent of an outside-inside ratio of 60 : 40. [14C]Lysophosphatidylcholine introduced into the outer monolayer of such vesicles by intervesicular transfer of lysophosphatidylcholine remains virtually completely available for hydrolysis by lysophospholipases, corroborating the interpretation that transbilayer movement of lysophosphatidylcholine in these vesicles is an extremely slow process.In handshaken liposomes consisting of 5 mol% 1-palmitoyl lysophosphatidylcholine and 95 mol% egg phosphatidylcholine 15–20% of lysophosphatidylcholine is readily available for exogenous lysophospholipase. This pool may represent lysophosphatidylcholine in the outer monolayer of the liposomes. 相似文献
48.
Intercropping as a method to reduce crop losses is an old technique, especially in the tropics. During 1977 and 1978 intercropping experiments of Brussels sprouts with Spergula arvensis showed a significant pest reducing effect. Mamestra brassicae and Evergestis forficalis populations showed a strong reduction, whereas Pieris rapae did not seem to respond to intercropping. Late cabbage root fly infestation of the sprout buttons was reduced drastically. Brevicoryne brassicae incidence was decreased in dense intercropping plots only. Injury due to caterpillar feeding showed a grading response to intercropping density, as did the total caterpillar populations. Log dose-effect regression lines allow a comparison of various intercropping densities with other control methods on insect pest population reducing potential.
Zusammenfassung Durch Untersaaten können Ertragsverluste an Kulturpflanzen reduziert werden. Das ist ein altes, bewährtes Verfahren, besonders in den Tropen. Die Einsaat von Spergula arvensis in Rosenkohlbeständen führte in 2-jährigen Untersuchungen zur signifikanten Verringerung des Schädlingsbefalls. Während die Populationen von Mamestra brassicae und Evergestis forficalis stark zurückgingen, blieb die von Pieris rapae unbeeinflusst. Eine Abnahme von Brevicoryne brassicae konnte nur in Parzellen mit hohen Spergula-Dichten festgestellt werden. Die Abundanz der Raupen sowie die Beschädigungsintensität durch diese, zeigten eine Abhängigkeit von der Untersaatdichte. Die Regressionsgerade Untersaatdichte zur Effektivität erlaubt einen Vergleich verschiedener Spergula-Dichten mit anderen Methoden, die das Schädlingspotential reduzieren.相似文献
49.
W E Borrias M Hagenaar R Van Den Brekel C Kühlemeijer P J Weisbeek 《Journal of virology》1979,31(2):288-298
Mutants of bacteriophage G4 were isolated and characterized, and their mutations were mapped. They constitute six different genes, namely, A, B, E, F, G, and H. The functional relationship with bacteriophage phi X174 was determined by complementation experiments using amber mutants of phi X and amber mutants of G4. Bacteriophage phi X was able to use the products of G4 genes E, F, G, and H. In bacteriophage G4, however, only the phi X gene H product was functional. 相似文献
50.
Summary A malformed male newborn with partial trisomy for the distal part of the long arm chromosome 14 (14q2314qter) is described. This anomaly arose as a segregation product of a balanced t(14q-, 11q+), translocation in the father. 相似文献