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1.
A collecting expedition has been carried out in the inland areas of the Basilicata Region, South Italy. Each of the 14 selected municipalities was subdivided in three strata based on the geographical distribution of population and orography: 1. city boundaries, 2. group of country houses, 3. isolated farm houses. Five sites were selected within each stratum/town for a total of 185 sites. In 101 sites crop species germplasm was collected and the farmer-maintainers were interviewed. Altogether 350 accessions were collected, the most common species were Capsicum annuum, Lycopersicon esculentum and Phaseolus vulgaris. A significant number of landraces are still preserved on farm, mostly in isolated farm houses (average age of farmers: 60?years) adopting traditional farming systems but a number of young farmers were also present. Perspectives for on farm conservation and management are discussed and public economic support for “farmer-maintainers” proposed.  相似文献   
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The new diterpenes brussonol (1) and iguestol (6alpha,11-dihydroxy-12-methoxy-abieta-8,11,13-triene) (2) with an icetexane and a dehydroabietane skeleton, respectively, have been isolated from hairy root cultures of Salvia broussonetii. Other previously known diterpenes, 7-oxodehydroabietane, 11-hydroxy-12-methoxyabietatriene, taxodione, inuroyleanol, ferruginol, deoxocarnosol 12-methyl ether, cryptojaponol, pisiferal, sugiol, isomanool, 14-deoxycoleon U, 6alpha-hydroxydemethylcryptojaponol, demethylsalvicanol, and demethylcryptojaponol, were also obtained from these roots. The insect antifeedant and toxic effects of several of these compounds were investigated against the insect pests Spodoptera littoralis and Leptinotarsa decemlineata. Additionally, their comparative cytotoxic effects were tested on insect Sf9 and mammalian CHO cells. Demethylsalvicanol (4) was a moderate antifeedant to L. decemlineata, whereas brussonol (1) was inactive. 14-Deoxycoleon U (15) was the strongest antifeedant, whereas demethylcryptojaponol (11) was toxic to this insect. None of these compounds had antifeedant or negative effects on S. littoralis ingestion or weight gains after oral administration. Demethylcryptojaponol (11) was cytotoxic to mammalian CHO and insect Sf9 cell lines, followed by the icetexane derivative brussonol (1), with moderate cytotoxicity in both cases. The remainder of the test compounds showed a strong selective cytotoxicty to insect Sf9 cells, with demethylsalvicanol (4) being the most active.  相似文献   
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The red kite (Milvus milvus) occurs in a relatively small area in the southwestern Palearctic region, with population strongholds in Central Europe. Following strong human persecutions at the beginning of the 20th century, populations have receded, particularly in peripheral areas and islands. In order to describe and compare levels of genetic diversity and phylogeographic patterns throughout its entire distribution in Europe, sequence variation of a 357 bps part of the mitochondrial DNA control region was assessed in eight populations and 105 individuals. Overall, results indicate that population declines have affected red kite mtDNA variation. We found low levels of genetic diversity (values of nucleotide diversity ranging from 0 in Majorca island to 0.0062 in Central Europe), with only 10 distinct haplotypes, separated by low levels of genetic divergence (mean sequence divergence = 0.75%). Highest haplotype and nucleotide diversities match with demographic expectations, and were found in Central European and Central Spanish samples, where present strongholds occur, and lowest values in the declining southern Spanish and insular samples. Φst estimates indicated moderate gene flow between populations. Phylogeographic patterns and mismatch distributions analyses suggest central European regions may have been colonized from southern glacial refugia (in the Italian or Iberian peninsulas). Interspecific phylogenetic comparisons and divergence date estimates indicated the genetic split between the red kite and its closely related species, the black kite (Milvus migrans), might be relatively recent. The low level of genetic variation found in the red kite mitochondrial control region, compared to the black kite, is likely the result of relatively recent divergence (associated with founder events), successive bottlenecks and small population sizes. As there are several ongoing projects aimed at reinforcing populations in countries such as the United Kingdom, Italy or Spain, our results may prove useful for the genetic management of the species.  相似文献   
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Three known Cinchona alkaloids of the quinine type, quinine (1), cupreine (2), cinchonine (3), and the possible artifact cinchonine-HCl (3-HCl), along with two new ones, acetylcupreine (4) and N-ethylquinine (5), have been isolated from the bark of Remijia peruviana (Rubiaceae). Their stereochemical structures were established by high resolution NMR spectroscopy. Alkaloids 2-4 had antifeedant effects on Leptinotarsa decemlineata with varying potencies. Compound 4 was cytotoxic to both insect Sf9 and mammalian CHO cells after 48 h of incubation, while 3-HCl had stronger and selective cytotoxicity to Sf9. Quinine 1 had a moderate to low effect on Trypanosoma cruzi. Tumoral cells were also affected by these alkaloids, with 4 and 3-HCl being the most cytotoxic to all the cell lines tested. Overall, the 8R, 9S configurations, as in 3 and 3-HCl, as well as the C-6'acetylated alkaloid 4, with an 8S, 9R configuration, showed stronger biological effects.  相似文献   
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In a total of 2653 slaughter pigs of the breeds Large White, Pi?train and Belgic Land Race the hearts were examined grossly ad histopathologically as to the occurrence of endocardiosis of the atrioventricular valves. This lesion occurred with high incidence. Endocardiosis of the V. mitralis was diagnosed in 63.2% and endocardiosis of the V. tricuspidalis in 17.7% of pigs. In 33.6% of animals the valves proved to be normal. Possible pathogenetic factors are briefly discussed.  相似文献   
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The silphinenes are tricyclic sesquiterpenes that have antifeedant and toxic effects in insects and structural similarity to the known GABA antagonist, picrotoxinin. In murine synaptoneurosomes, silphinenes block GABA-stimulated influx of 36Cl with EC50s in the range of 10-30 μM. In insects, silphinenes were tested in neurophysiological recordings of central neurons from third instar Drosophila melanogaster larvae. Silphinenes reversed the blockage of neuronal firing induced by GABA, but had little effect below 100 μM. The structure-activity profile observed in the murine chloride flux assay was also observed in the larval neurophysiological assay, indicating little selectivity for the silphinenes. A reference silphinene was equally active on nerve preparations from the rdl strain of D. melanogaster, which is resistant to channel-blocking antagonists via an altered GABA receptor. This latter finding suggests that silphinenes interact with the insect GABA receptor in a manner somewhat different from PTX, and that rdl resistance in the field may have little effect on silphinene efficacy.  相似文献   
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Ten accessions of wild Borago officinalis were collected during missions in the course of a research activity carried out on plants producing nutraceutical compounds. The aim was to identify populations that produce a higher content of γ-linolenic acid, as this compound has important therapeutic properties and has been used in medical tests to treat rheumatoid arthritis, eczema, and psoriasis with good therapeutical results. The present study reports on the characterization of both the polyunsaturated fatty acid composition and on genetic diversity estimated by means of AFLP markers in several B. officinalis accessions collected in Southern Italy and grown in isolation by means of screen houses specifically designed for each single population. Polyunsaturated fatty acid were found in different amounts in all investigated accessions. The populations were very variable at the molecular level, and the analysis of relationships based on AFLP data, showed that similarity based on Jaccard’s index ranged between 0.330 and 0.742. Our investigations allowed us to identify a population that may be considered as a good source of GLA.  相似文献   
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