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81.
The isolation and identification of four polyacetylenes is reported from the roots of Leuzea carthamoides. The compounds belong to a uniform series of thiophene acetylenes two of the compounds are new, whereas two are already known. 相似文献
82.
J. C. Sanford K. A. Skubik B. I. Reisch 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1985,69(5-6):571-574
Summary Experiments were conducted to test the validity of previous reports of pollen-mediated plant transformation utilizing genomic donor DNA. Multiple Mendelian markers were employed in Zea mays L. and Lycopersicon esculentum Mill, to detect transformation events. Pollen from multiple recessive (recipient) lines was incubated with genomic DNA from multiple dominant (donor) lines, under various conditions. Treated pollen was subsequently used for pollinations on multiple recessive females, and resulting seeds were screened for transformation events. Over 200 crosses were made in tomato, and over 80 crosses were made in corn. Over 600 resulting seedlings were tested in tomato and over 800 seeds were screened in corn. Because multiple markers were used, 4,937 potential transformation events were screened. No clear-cut transformation events were observed. Therefore, using well-defined multiple markers, we have been unable to confirm the earlier claims of high efficiency pollen-mediated transformation employing genomic donor DNA. 相似文献
83.
R V Carsia N M Reisch M J Fennell H Weber 《Proceedings of the Society for Experimental Biology and Medicine. Society for Experimental Biology and Medicine (New York, N.Y.)》1987,185(2):223-232
The effect of orchiectomy and androgen replacement on cockerel adrenocortical function was investigated. Orchiectomized cockerels (2 weeks old) were implanted with Silastic tubing containing various amounts of one of the following steroids: cholesterol, testosterone (T), androstenedione (A4), and 5 alpha-dihydrotestosterone (DHT). Birds were administered additional implants, containing doses of steroids equivalent to those of the initial implants, at 4 and 8 weeks of treatment (i.e., 6 and 10 weeks of age). Sham-operated cockerels administered empty implants served as intact controls for comparison of data. Animals were killed after 10 weeks of treatment (12 weeks old). Trunk plasma corticosterone (B) and plasma T, and B production by collagenase-isolated adrenocortical cells incubated briefly (2 hr) with or without steroidogenic agents were measured by radioimmunoassay. Orchiectomy with implantation of the inert sterol, cholesterol (hereafter referred to as orchiectomy), did not alter plasma B concentrations and did not affect basal cellular B production or cellular B production induced by a maximal steroidogenic concentration of ACTH or that maximally supported by 25-hydroxycholesterol. However, orchiectomy did lower maximal 8-bromo-cyclic AMP-induced B production by 30%. Low-implant doses of A4 (1-cm implant) and T (0.3-cm implant), that maintained comb growth, lowered plasma B concentrations by 24-42%, whereas a high-implant dose of T (3-cm implant) and all implant doses of DHT had no effect on plasma B concentrations. Thus, androgen replacement had different effects on plasma B depending on the type of androgen and the implant dose. In contrast, androgen replacement consistently suppressed basal and maximal ACTH-induced cellular B production regardless of the type of androgen. Furthermore, the degree of suppression was dose-dependent. These results suggest that the differential effect of androgen replacement on plasma B concentrations was due to differences in the clearance of circulating B and/or differences in blood volume. In addition, the present study suggests that in the absence of the testes, androgens are suppressants of adrenocortical cell function in the domestic fowl. 相似文献
84.
J. C. Sanford Y. S. Chyi B. I. Reisch 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1984,68(3):269-275
Summary Experiments were conducted to determine if egg transformation could be achieved in Zea mays L. as described by Pandey in Nicotiana L. Multiple recessive and multiple dominant marker stocks were employed, as well as a tester and a donor line for the En transposable element. Recipient tester females were pollinated with dominant donor pollen, which was applied in several treatment combinations. The pollination treatments included: 1) pollen irradiated at 20, 30, 40, 80, and 100 Krad; 2) pollen irradiated with the same doses, mixed with non-irradiated recipient pollen; 3) pollen irradiated at 80 Krad, followed by self pollination delayed 18 h; 4) non-irradiated donor pollen mixed with non-irradiated recipient pollen. Zero seed were produced from 100 pollinations with irradiated pollen. There were 258 pollinations made with irradiated donor plus self pollen mixtures, producing over 21,300 seed. Of these seed, 3 were unexpected. One was clearly from pollen contamination, one was clearly derived from a pre-meiotic mutation, and the third occurred as a mutant sector in the seed's endosperm. There were 56 pollinations with non-irradiated pollen mixtures, producing over 5,000 seed. Among these seed, there were 7 unexpected seed. Three of these were clear-cut cases of heterofertilization. Four progeny were dominant for all seed and seedling markers except one endosperm marker. These cases appear to represent spontaneous recessive endosperm mutations. More than 59,000 potential transformation events were screened producing only 6 apparent mutations. It is concluded that if egg transformation occurs in Zea mays, it is a very rare event, and is not likely to be useful in corn improvement.Approved by the Director of the New York State Agricultural Experiment Station for publication as Journal Paper No. 3556 相似文献
85.
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88.
A diprenylated chromenoflavanone has been characterized from the root bark of Amorpha fruticosa. 相似文献
89.
Zusammenfassung Topochemisch konnten im Kaninchenthymus Ketosteroide nachgewiesen werden, für deren Vorhandensein die chemische Analyse von Thymuslipidextrakten Hinweise ergeben hatte. Die Darstellung der Ketosteroide erfolgte mit der NAHD-Reaktion (Camber, 1949). Diese Befunde dürften als spezifisch gelten, da eine Verfälschung durch freie Gewebsaldehyde, Plasmalogene (Gomori, 1952) und Corticosteroide (Khanolkar et al., 1958) ausgeschlossen wurde.Mit Hilfe der Camber-Methode konnten Granula bestimmter Zellen des Kaninchenthymus selektiv dargestellt werden, die auf Grund morphologischer Kriterien in zwei Gruppen unterteilt wurden. Die Zellen liegen im gesamten Thymusparenchym sowie im Bindegewebe der Septen und der sogenannten Kapsel. Prädilektionsorte stellen die Umgebung der Hassallschen Körperchen, die Mark-Rinden-Grenze, der intra- und perivasale Raum sowie die subkapsuläre Zone dar.Beide Zellgruppen sind Sudan III-, PAS- und Eosin-positiv, besitzen eine ausgeprägte gelbgrüne Eigenfluoreszenz und können differentialdiagnostisch gegen Mastzellen abgegrenzt werden. Elektronenmikroskopisch zeigen beide Zellgruppen zahlreiche Übereinstimmungen mit Reifestadien eosinophiler Knochenmarkszellen.
Topochemical demonstration of carbonyl compounds in the thymus
Summary Ketosteroids were demonstrated topochemically in the rabbit thymus following indications given by chemical analysis of thymus lipid extracts. They were revealed by means of the NAHD-reaction (Camber, 1949). The results are thought to be specific, because adulteration by free tissue aldehydes, plasmalogens (Gomori, 1952) and corticosteroids (Khanolkar et al., 1958) can be excluded.The Camber-method selectively reveals the presence of two groups of morphologically differentiable granules in specific rabbit thymus cells which are distributed throughout the entire thymic parenchyme as well as in the connective tissue of the septa and the in so-called capsule. They are mainly seen in the vicinity of Hassall's bodies, in the zone between medulla and cortex, the intra- and perivascular space and in the subcapsular space.Both cell groups are Sudan III-, PAS- and eosin-positive, show intensive yellow-green primary fluorescence and can be distinguished from mast cells by differential diagnosis.Electron microscopy reveals that both cell groups show many similarities with the maturation phase of bone marrow eosinophils.
Institut für Pharmazeutische Chemie der Westfälischen Wilhelms-Universität Münster. 相似文献
90.
Glacial refugia and postglacial expansion of the alpine–prealpine plant species Polygala chamaebuxus
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Tobias Windmaißer Stefan Kattari Günther Heubl Christoph Reisch 《Ecology and evolution》2016,6(21):7809-7819
The shrubby milkwort (Polygala chamaebuxus L.) is widely distributed in the Alps, but occurs also in the lower mountain ranges of Central Europe such as the Franconian Jura or the Bohemian uplands. Populations in these regions may either originate from glacial survival or from postglacial recolonization. In this study, we analyzed 30 populations of P. chamaebuxus from the whole distribution range using AFLP (Amplified Fragment Length Polymorphism) analysis to identify glacial refugia and to illuminate the origin of P. chamaebuxus in the lower mountain ranges of Central Europe. Genetic variation and the number of rare fragments within populations were highest in populations from the central part of the distribution range, especially in the Southern Alps (from the Tessin Alps and the Prealps of Lugano to the Triglav Massiv) and in the middle part of the northern Alps. These regions may have served, in accordance with previous studies, as long‐term refugia for the glacial survival of the species. The geographic pattern of genetic variation, as revealed by analysis of molecular variance, Bayesian cluster analysis and a PopGraph genetic network was, however, only weak. Instead of postglacial recolonization from only few long‐term refugia, which would have resulted in deeper genetic splits within the data set, broad waves of postglacial expansion from several short‐term isolated populations in the center to the actual periphery of the distribution range seem to be the scenario explaining the observed pattern of genetic variation most likely. The populations from the lower mountain ranges in Central Europe were more closely related to the populations from the southwestern and northern than from the nearby eastern Alps. Although glacial survival in the Bohemian uplands cannot fully be excluded, P. chamaebuxus seems to have immigrated postglacially from the southwestern or central‐northern parts of the Alps into these regions during the expansion of the pine forests in the early Holocene. 相似文献