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41.
This article represents only a brief glimpse into one of the fascinating aspects of the chemistry of electronically excited molecules. More exhaustive coverage of synthetic applications of photochemical reactions may be found in texts and reviews. We summarize here by noting that classification of reliable photoreactions is possible, but that the most effective application of the classification scheme requires a familiarity with some of the special features of the chemistry of electronically excited states. Thus, knowledge of the properties of singlet and triplet states, the factors which determine photochemical efficiency and reactivity, and the special technical aspects of photochemical procedures such as selective direct and phtosensitized excitation and photoexcitation at low temperatures or solid matrices make photochemistry a useful tool for the construction of organic molecules. It is our hope that the material and flavor of this article will whet the intellectual and experimental appetites of researchers who are concerned with various aspects of the synthesis of oganic molecules. 相似文献
42.
Three rhesus monkeys Macaca mulatta, formerly dependent on morphine, had increased sensitivity to nalorphine's effect of suppressing operant responding for food, as compared with two monkeys with no history of morphine exposure. Within the dose range employed, nalorphine injections produced emesis, salivation, and hyperirritability in formerly morphine-dependent monkeys but not in controls. 相似文献
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Gerardo Domingo Lucio Cervigni Ivan Schuster Everaldo Gonçalves de Barros Maurílio Alves Moreira 《Euphytica》2004,135(1):99-105
The purpose of this work was to identifymicrosatellite markers linked to a gene forresistance to Heterodera glycinesIchinohe (Soybean Cyst Nematode – SCN) insoybean cultivar Hartwig. ABC1F2 mapping population derivedfrom a cross between Hartwig (resistant)and the Brazilian soybean line Y23(susceptible) was used. About 200microsatellite or simple sequence repeat(SSR) primer pairs were tested in a bulkedsegregant analysis (BSA). Those thatshowed clear polymorphisms were amplifiedin the BC1F2 population, whichhad been previously inoculated andevaluated for resistance/susceptibility toSCN Race 3. Three SSR markers linked toSCN resistance were detected in thepopulation. Two of them, Satt 038 and Satt163, flanking a dominant resistant gene(d/a = –0.90), explained 37% of thephenotypic variance. This gene was mappedat the edge of molecular linkage group G. Broad and narrow sense heritabilities wereestimated to be 50.54% and 37.73%,respectively. A selection efficiency of91.18% was obtained with the simultaneoususe of the two markers. The identified SSRmarkers will be useful tools for assistingthe selection of homozygous genotypes andfor expediting the introgression of the SCNresistance locus from cv. Hartwig tosoybean elite cultivars. 相似文献
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Resistance of Fasciola hepatica to triclabendazole 总被引:1,自引:0,他引:1
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A possibility was shown, how to quantify the water content of nitrogen and COD (Chemical Oxygen Demand) from intensive fish production, independent of flow rate and feeding time. The nitrogen excretion could be reduced 50% by feeding a protein reduced fish feed (A: 38.4% XP) compared with an fish feed B contending 47.9% protein (XP). The excretion-compartments were evaluated with the waste water parameter COD. Doing this, it could be shown that the COD input by feed A is reduced 20% in opposite to feed B. Further more the separation of fish faeces would achieve an COD reduction from about 50% to 70%. 相似文献
50.
Serum and Tissue Steroid Hormone Levels in Canine Mammary Tumours: Clinical and Prognostic Implications
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FL Queiroga D Pérez‐Alenza A González‐Gil G Silván L Peña JC Illera 《Reproduction in domestic animals》2015,50(5):858-865
Hormonal dependency of canine mammary tumours (CMT) has been studied over the last few decades. However, studies assessing the prognostic and predictive potential of serum and/or tissue steroid hormone levels are still scarce in CMT. To the best of our knowledge, this is the first report relating serum and tissue levels of steroid hormones and prognosis in dogs. Serum and tumour tissue from 45 female dogs with spontaneous CMT were included in the study. Moreover, serum and normal mammary tissue from 13 healthy female dogs were also included as controls. Steroid hormones were determined by competitive enzyme immunoassay. Overall, levels of steroid hormones in serum and tissue homogenates were significantly different between malignant and benign mammary tumours (p < 0.01), except for progesterone (P4) serum levels that revealed no statistical differences between groups. In malignant tumours, oestrone sulphate (SO4E1), dehydroepiandrosterone (DHEA), androstenedione (A4), testosterone (T) and P4 elevated tissue concentrations were significantly associated with tumour relapse and/or distant metastasis during follow‐up. A significant association was found between elevated tissue SO4E1 (p = 0.003), 17β‐oestradiol (E2) (p = 0.036), DHEA (p = 0.022), A4 (p = 0.001) and P4 (p = 0.013) concentrations and shorter disease‐free survival and overall survival in female dogs with malignant mammary tumours. The high levels of tissue steroids found in cases of poor prognosis open the possibility of additional new therapeutic approaches. Future clinical trials will be needed to clarify the usefulness of targeting steroid hormones in the treatment of this neoplastic disease. 相似文献