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61.
Von H. Karg M. Hartl B. Hoffmann D. Schams W. Schmidt Von O. Günzler E. Huber S. Müller 《Reproduction in domestic animals》1976,11(1):7-18
1. Durch intramuskulare Injektion von 0,5 mg des Prostaglandinanalogs ICI 80 996 beim Rind während der Gelbkörperphase des Zyklus kann nach 15–24 Stunden ein Abfall der Progesteronwerte unter 1 ng/ml Blutplasma und damit eine nachhaltige Luteolyse erreicht werden. Die sich anschließende Brunst ist ovulatorisch und feral. Das Präparat wird ohne Nebenwirkungen vertragen. 2. Durch zweimalige Injektion (d. h. je 1 mal 0,5 mg i. m.) im Abstand von 11 Tagen kann dieser Luteolyseeffekt zu Brunstsynchronisationen herangezogen werden; dabei ist eine Zykluskontrolle oder Brunstbeobachtung nicht erforderlich. 3. in 8 Feldversuchen konnte bei 213 Tieren ein Synchronisationserfolg von 90,6 % und, nach KB in der 1. induzierten Brunst, ein Konzeptionsergebnis von 54,7 % (bzw. von 60,1 %, wenn man die Auswertung auf die erfolgreich synchronisierten Tiere beschränkt) erzielt werden. Die KB bei 119 nicht behandelten Kontrolltieren, die in 5 dieser 8 Versuche zur Verfugung standen, war zu 60,3 % erfolgreich. 4. In einem Problembestand konnte die Fertilitätslage durch das biotechnische Vorgehen der Prostaglandinanwendung unmittelbar nicht verbessert werden 5. Die palpatorischen Ovarbefunde zum Zeitpunkt der KB ergaben, daß Tiere mit aprungbereiten Follikeln'zu 65 %, mit kleinen, nicht reifen Follikeln zu 50,8 % und mit bereitsgesprungenen Follikeln zu 15,8 % konzipierten. 6. Die bei einem Teil der Versuche eingesetzte zusdtzliche Behandlung mit 1,0 bzw. 1,5 mg des Gonadotropin-Releasinghormons (LRH-Hoechst 471) i. m. zum Zeitpunkt der Besamung zeigte bezüglich des Konzeptionsergebnisses eine positive Tendenz. 相似文献
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Promoter anchored amplified polymorphism based on random amplified polymorphic DNA (PAAP-RAPD) in cotton 总被引:1,自引:0,他引:1
Non-coding sequences account for a majority of the higher plant genome, some of which have important effects in gene regulation
and plant development. In an effort to develop molecular marker systems to search for polymorphisms associated with high fiber
yield and quality in cotton, we have developed a methodology that could specifically target the regulatory regions of the
cotton genome. In this study we designed 10-nucleotide degenerate promoter primers based on conserved core promoter sequences
and tested their applicability in PCR amplifications in combination with 10-mer random amplified polymorphic DNA (RAPD) primers.
The amplified markers are called promoter anchored amplified polymorphism based on RAPD (PAAP-RAPD). Forty cotton genotypes
with diverse genetic and geographical backgrounds were used to test the PAAP-RAPD system using polyacrylamide gel electrophoresis.
Based on PAAP-RAPD markers amplified from 12 primer combinations, the 40 genotypes were classified into five distinctive groups:
two Upland cotton (Gossypium hirsutum) groups from China, another two Upland cotton groups from the USA, and one group from American Pima cotton (G. barbadense). The groupings are in general consistent with their genetic and geographical origins. Thirty-six PAAP-RAPD and RAPD fragments
were cloned and four of them were further subjected to sequence analysis. Signal scanning using software PLACE confirmed that
they contained an array of cis-regulatory sequences in addition to the core promoter sequences. The results demonstrate the
potential application of PAAP-RAPD as a new marker system specifically targeting regulatory regions of the plant genome. 相似文献
65.
Max Hoffmann 《Journal of pest science》1970,43(5):74-75
Ohne Zusammenfassung 相似文献
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The cultivation of autumn sown sugar beet (winter beet) is supposed to result in a marked yield increase compared with spring sown sugar beet. Although the importance of the growth stage reached before winter for the survival of autumn sown sugar beet has already been shown, it is not clear to which extent osmotic and potentially frost protecting compounds may contribute to winter hardiness. The study thus aimed to analyse the acclimatization process of sugar beet to low temperatures and to identify compounds which are important for survival of frost. Field trials with autumn sown sugar beet were conducted at eleven environments in Germany from 2009/10 to 2012/13, which were accompanied by greenhouse experiments with controlled temperature regimes. In the field trials, the survival rates after winter varied from 0 % to 99 %, but only in four environments differences between the five genotypes occurred. During acclimatization, betaine, glutamine, proline and raffinose were markedly accumulated and osmolality was enhanced. In particular betaine, amino acids and osmolality showed a positive correlation to the survival rate and were thus identified as potentially frost protecting substances for sugar beet. In contrast, raffinose and proline seem to act rather as stress indicators as they were negatively related to survival. Possible frost protecting substances were identified which can be used in breeding to improve the winter hardiness of sugar beet. 相似文献
70.
The conservation of threatened frugivorous primates (e.g. chimpanzees) and birds in the Albertine Rift Ecoregion rainforests requires the conservation of food tree species aided by an understanding of their natural regeneration and population trends. However, little is known of the population structure and regeneration patterns of a wide range of multiple-use tree species in many of these forests. 相似文献