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21.
Evidence of hexaploid karyotype in shortnose sturgeon 总被引:1,自引:0,他引:1
Francesco Fontana Leonardo Congiu Vincent A Mudrak Joseph M Quattro Theodore I J Smith Kent Ware Serge I Doroshov 《Génome》2008,51(2):113-119
A karyotype analysis by several staining techniques was carried out on triplicate samples of the shortnose sturgeon, Acipenser brevirostrum. The chromosome number was found to be 2n = 372 +/- 6. A representative karyotype of 374 chromosomes was composed of 178 metacentrics/submetacentrics and 196 telocentrics/acrocentrics and microchromosomes. The signals of fluorescent in situ hybridization (FISH) with a HindIII satellite DNA probe were visible on 14 chromosomes. The signals obtained with a PstI satellite DNA probe appeared on 12 chromosomes. The FISH with a 5S rDNA probe revealed fluorescent signals on 6 chromosomes. These last results, compared with 2 signals in species with about 120 chromosomes and 4 in species with 240, support the hypothesis that A. brevirostrum is a hexaploid species, probably of hybrid origin. Based on these results, we propose a model explaining speciation events occurring in sturgeons by hybridization, genome duplication, and diploidization. 相似文献
22.
With the aim of elaborating a breeding plan on a captive stock of the highly endangered Adriatic sturgeon (Acipenser naccarii), a total of 10 polymorphic microsatellite loci were isolated from an enriched library. The results of cross amplification
of additional 8 loci previously isolated from A. oxyrinchus, A. fulvescens and Scaphyrinchus platorhynchus are also reported. Given the tetraploid condition of the species the genetic variability was estimated basing on the number
of alleles per individuals and the average band sharing. 相似文献
23.
It has been claimed that weak extremely low frequency electromagnetic fields (ELF‐EMFs) can affect biochemical reactions and a wide‐ranging body of literature is available on this topic. Nevertheless, the physical nature of these effects remains largely unknown. We investigated the influence of ELF‐EMF on glutamic acid solutions using Fourier transform infrared‐attenuated total reflectance (FTIR‐ATR) spectra. Samples were exposed for 10, 20, or 30 min to a weak EMF generated by Helmoltz coils, and then placed in a spectrometer. After exposure, those solutions that had a pH lower than the isoelectric point tended to show a shift toward the deprotonation of the carboxylic group, while solutions having a pH greater than the isoelectric point showed the deprotonation of the residual amine group. Moreover, at low pH values, we also detected a shift of the δantisym band of the amine. The effects lasted a few minutes after exposure before the native configuration was restored. The spectral modifications were observed after each independent exposure to EMFs, and the same effects were seen by varying the frequencies in the range of 0–7 kHz. Therefore, the hypothesis of the existence of a resonant frequency that has been proposed elsewhere cannot be supported by the results of this study. The most surprising characteristic of this effect is the long‐lasting nature of the perturbation, which is hard to be explained in terms of short‐living excitations in biological matter. Bioelectromagnetics 32:218–225, 2011. © 2010 Wiley‐Liss, Inc. 相似文献
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P. Pani A. Columbano S. Dessì M. Porcu L. Congiu 《Chemico-biological interactions》1976,15(2):107-116
The effect of lead nitrate, an inhibitor of the hepatic drug-metabolizing enzyme system upon the acute hepatotoxicity of dimethylnitrosamine (DMN) was studied.Lead pretreatment significantly prevented polysomal disaggregation induced by the nitrosamine. Cell necrosis, evaluated morphologically and by the release of serum glutamic-pyruvic transaminase (GPT), was also diminised.The metabolism of DMN in rats pretreated with lead nitrate was investigated by following its clearance from blood and by determining, in vitro the demethylation of the nitrosamine. Lead increased, although not significantly, the clearance of DMN from blood, but it lowered the activity of DMN-demethylase 24 h after its administration.Finally, lead lowered the lethal effects of DMN. The mechanism by which lead influenced DMN toxicity is discussed. 相似文献
28.
Filomena De Biasio Lea Riviello Daniele Bruno Annalisa Grimaldi Terenzio Congiu Yu Feng Sun Patrizia Falabella 《Insect Science》2015,22(2):220-234
Odorant‐binding proteins (OBPs) are soluble proteins mediating chemoreception in insects. In previous research, we investigated the molecular mechanisms adopted by aphids to detect the alarm pheromone (E)‐β‐farnesene and we found that the recognition of this and structurally related molecules is mediated by OBP3 and OBP7. Here, we show the differential expression patterns of 5 selected OBPs (OBP1, OBP3, OBP6, OBP7, OBP8) obtained performing quantitative RT‐PCR and immunolocalization experiments in different body parts of adults and in the 5 developmental instars, including winged and unwinged morphs, of the pea aphid Acyrthosiphon pisum. The results provide an overall picture that allows us to speculate on the relationship between the differential expression of OBPs and their putative function. The expression of OBP3, OBP6, and OBP7 in the antennal sensilla suggests a chemosensory function for these proteins, whereas the constant expression level of OBP8 in all instars could suggest a conserved role. Moreover, OBP1 and OBP3 are also expressed in nonsensory organs. A light and scanning electron microscopy study of sensilla on different body parts of aphid, in particular antennae, legs, mouthparts, and cornicles‐cauda, completes this research providing a guide to facilitate the mapping of OBP expression profiles. 相似文献
29.
A new series of 2-amino-6-(2-alkyl or arylidenehydrazinyl)-4-(dialkylamino)pyrimidine-5-carbonitriles, 5-24, were synthesized in satisfactory overall yield, using 2-amino-4-(dialkylamino)-6-hydrazino-5-pyrimidinecarbonitriles 3, 4, as key intermediates, by applying classical synthetic methods to construct the hydrazone moiety at C-6 of the pyrimidine ring. Hydrazinopyrimidine derivatives 5-24 were evaluated for their in vitro anticancer activity toward cell lines of nine different types of human cancers. Some of the newly prepared compounds demonstrated inhibitory effects on the growth of a wide range of cancer cell lines generally at 10(-5)M level and in some cases at 10(-7)M concentrations. 相似文献
30.
Cenzo Congiu Valentina Onnis Loredana Vesci Massimo Castorina Claudio Pisano 《Bioorganic & medicinal chemistry》2010,18(17):6238-6248
A series of 3,5-diaryl-4,5-dihydropyrazole regioisomers, and their 1-acetylated derivatives, bearing a 3,4,5-trimethoxyphenyl moiety combined with a variety of substituted phenyl rings, was synthesized and evaluated for antitumor activity. Results of the in vitro assay against a non-small cell lung carcinoma cell line (NCI-H460) showed several compounds to be endowed with cytotoxicity in micromolar to sub-micromolar range, depending on substitution pattern and position of aryl rings on 4,5-dihydropyrazole core. Potent and selective activity was also observed in the NCI 60 human cancer cell line panel. 5-(3,4,5-Trimethoxyphenyl)pyrazolines 31 and 39 were found to possess potent antiproliferative activity against SR and MDA-MB-435, with GI50 inhibitory values in nanomolar range. Structure–activity relationships revealed that introduction of a (hydroxy)acetyl group at N-1 of inactive 5-(3,4,5-trimethoxyphenyl)pyrazolines, results in a clear in vitro activating effect. Compound 31 (IC50 = 5.16 μM) showed inhibition of tubulin polymerization comparable to that of CA-4 (IC50 = 4.92 μM). 相似文献