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1.
2.
The activity of five experimental fungicides combining structural elements responsible for sterol C-14 demethylase inhibition and sterol nuclear double-bond transformations has been investigated by examining sterol accumulation in Ustilago maydis (DC.) Corda, inhibition of sterol-biosynthesis enzymes in Saccharomyces cerevisiae Meyer using a cell-free system and protective activity in cereals against Erysiphe graminis DC. and Puccinia coronata Corda. Combining the fenpropidin/fenpropimorph basic structure with a pyridine moiety offered no advantage in fungicidal activity. However, the combination of the pyrifenox structure with a morpholine moiety yielded a compound which was a good inhibitor of C-14 demethylase and Δ8 → Δ7 isomerase in vitro and gave good cereal protection.  相似文献   
3.
Hohmann J  Forgo P  Szabó P 《Fitoterapia》2002,73(7-8):749-751
Investigation of the alkaloid fraction of the bulbs of Hymenocallis x festalis yielded a new natural product, 3-methoxy-8,9-methylenedioxy-3,4-dihydrophenanthridine (1). The structure was elucidated on the basis of spectroscopic data.  相似文献   
4.
Zusammenfassung Bei 112 Linien 25 verschiedener BTT-Systeme erwies sich die genetische Stabilität der Systeme in den meisten Fällen als gut bis sehr gut, gemessen an der Frequenz disom-fertiler Rekombinanten. In speziellen Kreuzungstests ergaben sich Hinweise auf mögliche Stabilitätsstörungen durch Pollentransmission des Zusatzchromosoms nur bei einem von neun geprüften Systemen.Die Vitalität der trisomen Pflanzen bei den verschiedenen BTT-Systemen ist sehr unterschiedlich und von der jeweils vorliegenden Segmentzusammensetzung des Zusatzchromosoms abhängig. Bezogen auf diploide Pflanzen gibt es alle Übergänge von Subletalität bis hin zu annähernd normaler Vitalität. Leistungsfähige BTT-Systeme sind relativ selten und können mit ausreichender Wahrscheinlichkeit nur entwickelt werden, wenn von einer genügend breiten Basis von Translokations-undmsg-Linien ausgegangen wird.
Studies on the stability and viability in systems of balanced tertiary trisomy in barley
Summary The genetic stability of 112 stocks out of 25 different BTT systems proved to be, in most cases, good to very good, in terms of the frequency of disomic fertile recombinants. There is only rare indication of instability caused by pollen transmission of the extra chromosome: In special crossing tests only one out of nine BTT systems tested showed transmission.The viability of trisomic plants is very diverse in the different BTT systems and depends on the specific segmental composition of the extra chromosome. As compared with normal diploids there are all types of trisomics ranging from sublethal to nearly normal ones. Efficient BTT systems are comparatively rare. They can be developed with good expectation provided a sufficiently broad basis of translocation andmsg lines is used.

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Herrn Professor Dr. Dr. h. c. mult.H. Stubbe zum 85. Geburtstag gewidmet.  相似文献   
5.
Processed aconite drugs are widely used in Eastern medicine as painkillers and antirheumatic agents. It is known that the traditional processing of aconite drugs increases the amount of lipo-alkaloids. In order to obtain information about the pharmacological potential of these compounds, semisynthesis of 9 aconitine-derived lipo-alkaloids was carried out and their COX-1, COX-2 and LTB4 formation inhibitory activities were investigated. It was found that compounds esterified with unsaturated fatty acids demonstrated significant COX-2 inhibitory effects, while in the COX-1 assay only 14-benzoylaconine-8-O-eicosapentaenoate exerted remarkable activity. The inhibition of LTB4 formation was pronounced in cases of long chain fatty acid derivatives.  相似文献   
6.
Nociceptive neuronal circuits are formed during embryonic and postnatal times when painful stimuli are normally absent or limited. Today, medical procedures for neonates with health risks can involve tissue injury and pain for which the long-term effects are unknown. To investigate the impact of neonatal tissue injury and pain on development of nociceptive neuronal circuitry, we used an animal model of persistent hind paw peripheral inflammation. We found that, as adults, these animals exhibited spinal neuronal circuits with increased input and segmental changes in nociceptive primary afferent axons and altered responses to sensory stimulation.  相似文献   
7.
耐盐性Imt1基因表达载体的构建及其在酵母中的高效表达   总被引:2,自引:0,他引:2  
 将Imt1(Inositol O-methyltransferase,肌醇甲基转移酶)构建成酵母表达载体pBD#-3,在酵母双突变体gpd#+(-)(glycerol 3-phosphate-dehydrogenase,3-磷酸甘油脱氢酶)中高效表达,使gpd#+(-)突变株对氯化钠的耐性由2.5%提高到5.0%。生化分析表明,在每mg干酵母细胞内积累高达2.2nmol的Ononitol(芒柄醇)含量。Western blot分析证明了Imt1基因的表达。这一研究为植物耐盐基因工程开辟了一条新途径。  相似文献   
8.
Plant and animal species present on a coal fly ash slurry pond site and a dry deposit site were surveyed and sampled during a two-day period in October. Elemental analyses were determined for most of the species encountered. A total of 48 plant species were observed on the two sites, with 35 species on the wet site, and 20 on the dry site. Eighteen terrestrial and 7 aquatic animal species were found on the wet site, exclusive of vertebrates which were not studied with the exception of a carp (Cyprinus carpio). Eleven terrestrial invertebrates and one aquatic species were observed on the dry site. Neutron activation analysis was carried out for: Se, Hg, Cr, Ni, Zn, Co, Sb, Cd, and As. Using literature values for phytotoxicity, we conclude that, in general, plants did not accumulate toxic levels of metals. Only one plant (Impatiens biflora Willd.) showed a significant level of Cd. Of 20 plants analyzed on the wet site, 10 had excessive Se concentrations (>5 ppm); on the dry site 6 out of 18 had high Se values. In animals (Gryllus sp.; Melanoplus sp.; Trachelipus sp.; Lumbricus terrestris; Physa integra; Cyprinus carpio) the trace metal concentration was generally in between that of control animals and that of the fly ash itself. One exception included Zn, which, although the most variable element examined, was concentrated in all the terrestrial animals to levels higher than in fly ash. Crickets are the most consistent bioconcentrators with Cr, Se, and Zn at higher levels than for control animals. All animal species studied accumulated Se compared to controls.  相似文献   
9.
Zusammenfassung Nach Einwirkung von Nitrosomethylharnstoff (NMH) auf Gerstenkaryopsen wurden die Prozentsätze geschädigter Zellen mit Chromosomenaberrationen in der mittleren Anaphase bis frühen Telophase für Wurzel- und Sproßmeristem im 1. Mitosezyklus der Keimung ermittelt. Eine geringfügig stärkere Wirkung auf das Wurzelmeristem ist nicht signifikant.Eine Vorbehandlung mit Äthylendiaminotetraessigsäure (ÄDTE) sensibilisierte die Chromosomen gegenüber der radiomimetischen Wirkung von NMH in beiden Meristemen. Der durch ÄDTE verursachte Sensibilisierungseffekt betraf das Wurzelmeristem in signifikant stärkerem Maße als das Sproßmeristem.Unterschiede in der Permeabilität und im Mitoserhythmus zwischen Sproß-und Wurzelmeristem konnten als mögliche Ursachen der beobachteten Differenzen ausgeschlossen werden. Es wird vermutet, daß die ermittelten Differenzen in kausalem Zusammenhang mit stoffwechselphysiologischen Verschiedenheiten zwischen beiden Meristemen stehen.Die Befunde zeigen, daß im Wurzelmeristem ermittelte Chromosomenaberrationsfrequenzen nicht ohne weiteres auf das Sproßmeristem übertragen werden dürfen, wie das vielfach geschieht.
Summary The percentages of damaged cells with chromosomal bridges or fragments in the middle ana- to early telophase were determined in barley seeds treated with nitrosomethylurea (NU), after various recovery times in the first mitotic cycle, both for shoot and root meristems. A slightly higher effect in the root meristem is not significant.Pretreatment with ethylenediaminetetraacetic acid (EDTA) sensitized the chromosomes against the radiomimetic effects of NU in both meristems. This EDTA-dependent sensitization affected the root meristem to a significantly greater extent than the shoot meristem.Differences in permeability or in duration of mitosis could be excluded as a possible cause for the observed differences. It appears probable that the found differences are caused by specific metabolic features of both meristems.These findings indicate that one cannot infer, as sometimes done, the situation in the shoot meristem directly from the known frequencies of chromosomal aberrations in the root.

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10.
The efficacy of a combination of milbemycin oxime and praziquantel in preventing the establishment of experimentally induced heartworm (Dirofilaria immitis) infection was investigated in a study involving 24 young domestic short-hair cats. The animals were inoculated with 50 infective larvae on day 0. Subsequently they were divided into two groups of 12 animals each. The animals in group 1 were treated once with medicated tablets containing 4 mg milbemycin (minimum dose 2 mg/kg body weight) and 10 mg praziquantel (MILBEMAX) on day 30 after infection. Cats in group 2 received placebo tablets on the same day. On day 183 post-infection a blood sample was taken from each animal before euthanasia and necropsy. The blood samples were tested for the presence of microfilariae and the necropsied animals were examined for the presence of adult worms. Microfilariae were not found in any of the investigated cats. No heartworms were found in the animals in group 1 (treated with medicated tablets). Out of the 12 placebo-treated cats 1 was heartworm-free, whereas all the others were found to be infected with 1-3 adult heartworms.  相似文献   
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