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1.
The surnames of populations of the municipalities with Cimbro and Mòcheno origins are compared with each other and with other municipalities of the neighbourhood. This study starts from the supposition that a community of surnames shares a common cultural origin, maintained by reciprocal mobility. The analysis has been carried out by using estimates of the similarities between populations, the topological representations obtained by them and the spatial autocorrelation. On the whole, this research shows no evidence of peculiar distinctions between the populations that share Cimbro and Mòcheno origins compared to the neighbouring ones. Moreover, there is not any evident process of undifferentiated diffusion along all the directions. On the contrary, it is emphasized that belonging to the same geographic region and to the same administrative subdivision mostly influences the similarity between populations. The exception is the Cimbro municipality of Luserna, which presents a peculiar structure of surnames different from other municipalities of the same territory.  相似文献   
2.
Based on literature review and malacological collections, 168 native freshwater bivalve and five invasive species have been recorded for 52 hydrographic regions in South America. The higher species richness has been detected in the South Atlantic, Uruguay, Paraguay, and Amazon Brazilian hydrographic regions. Presence or absence data were analysed by Principal Coordinate for Phylogeny-Weighted. The lineage Veneroida was more representative in hydrographic regions that are poorer in species and located West of South America. The Mycetopodidae and Hyriidae lineages were predominant in regions that are richest in species toward the East of the continent. The distribution of invasive species Limnoperna fortunei is not related to species richness in different hydrographic regions there. The species richness and its distribution patterns are closely associated with the geological history of the continent. The hydrographic regions present distinct phylogenetic and species composition regardless of the level of richness. Therefore, not only should the richness be considered to be a criterion for prioritizing areas for conservation, but also the phylogenetic diversity of communities engaged in services and functional aspects relevant to ecosystem maintenance. A plan to the management of this fauna according to particular ecological characteristics and human uses of hydrographic regions is needed.  相似文献   
3.
A simple, accurate and precise high-performance liquid chromatographic method with fluorescence detection was developed and validated for the determination of gemifloxacin (GEM) in rat plasma using furosemide as internal standard (I.S.). Plasma samples were pretreated by direct deproteinization and all samples and standard solutions were chromatographed at 45°C using triethylamine solution (0.5%, v/v, pH 3.0±0.1), methanol and acetonitrile (63:30:7, v/v/v) as the mobile phase. Chromatographic resolution was achieved using a RP-C(18) column (Atlantis, Waters, 150 mm × 4.6 mm, 5 μm) at a flow rate of 1.0 mL min(-1) and an injection volume of 30 μL. The analytes were measured by fluorescence detection with excitation and emission wavelengths of 344 nm and 399 nm, respectively. The retention times for GEM and I.S. were approximately 7.5 and 12.6 min, respectively. The lower limit of quantitation (LLOQ) was 20 ng mL(-1) and the calibration curves were linear over a concentration range of 20-5000 ng mL(-1). The intra- and inter-day precisions, expressed by relative standard deviation (R.S.D.) were lower than 6.24% and 4.49%, respectively. The accuracy ranged from 91.3% to 112% and from 98.8% to 106% for the lower and upper limit of quantitation of the calibration curve, respectively. Ratio of peak area of analyte to I.S. was used for quantification of plasma samples. No interferences from endogenous substances were found. The recovery of GEM and I.S. from plasma was greater than 90%. Drug stability in plasma was shown at room temperature for 4h, after three freeze-thaw cycles for 24h, in freezer at -80°C for 60 days, and in the autosampler after processing for 12h. The utility of the assay was confirmed by the successful analysis of plasma samples from GEM pharmacokinetics studies in the rats after intravenous administration.  相似文献   
4.
Serum proteins may often serve as indicators of disease and is a rich source for biomarker discovery. However, the large dynamic range of proteins in serum makes the analysis very challenging because high-abundant proteins tend to mask those of lower abundance. A prefractionation step, such as depletion of a few high-abundant proteins before protein profiling, can assist in the discovery and detection of less abundant proteins that may prove to be informative biomarkers. In the present study, five different depletion columns were investigated considering efficiency, specificity, and reproducibility. Our research included quantitative determination of total protein, albumin, and immunoglobulin G (IgG) concentrations, one- and two-dimensional gels and mass spectrometric analysis of the serum samples before and after the depletion step. Our results showed that all five depletion columns tested removed albumin and IgG with high efficiency. We found that based on reproducibility and binding specificity, the Multiple Affinity Removal Column that removed a total of six high-abundant proteins (albumin, IgG, antitrypsin, IgA, transferring, and haptoglobin) offered the most promising depletion approach. Among the disposable (single-use) products, the ProteoExtract Albumin/IgG Removal kit displayed the best results. Depleted serum from the Multiple Affinity Removal column was further evaluated by 2-D gel electrophoresis (2-DE) analysis, and the results indicated increased resolution and improved intensity of low-abundant proteins in a reproducible fashion. Our study provides a comprehensive investigation of commercially available depletion columns and will be of high importance for future proteomic studies on serum samples.  相似文献   
5.
Seventy-six 2-phenylbenzimidazole derivatives were synthesized and evaluated in cell-based assays for cytotoxicity and antiviral activity against a panel of 10 RNA and DNA viruses. The most commonly affected viruses were, in decreasing order, CVB-2, BVDV, Sb-1, HSV-1, and YFV, while HIV-1 and VSV were not affected, and RSV, VV and Reo-1 were only susceptible to a few compounds. Thirty-nine compounds exhibited high activity (EC50 = 0.1–10 μM) against at least one virus, and four of them were outstanding for their high and selective activity against VV (24, EC50 = 0.1 μM) and BVDV (50, 51, and 53 with EC50 = 1.5, 0.8, and 1.0 μM, respectively). The last compounds inhibited at low micromolar concentrations the NS5B RdRp of BVDV and also of HCV, the latter sharing structural similarity with the former. The considered compounds represent attractive leads for the development of antiviral agents against poxviruses, pestiviruses and even HCV, which are important human and veterinary pathogens.  相似文献   
6.
A methodology for the rapid and quantitative analysis of phosphorylation sites in proteins is presented. The coupling of capillary high-performance liquid chromatography (HPLC) to electrospray ionization mass spectrometry (ESI-MS) allowed one to distinguish phosphorylation sites based on retention time and mass difference from complex peptide mixtures. The methodology was first evaluated and validated for a mixture of non-, mono-, and dityrosine-phosphorylated synthetic peptides, corresponding to the tryptic fragment 485–496 (ALGADDSYYTAR) of the human protein tyrosine kinase ZAP-70. The limits of detection for the non-, mono- and diphosphorylated peptides were about 15, 40 and 100 fmol, respectively, when using a 300 μm I.D. column. Application of the method was extended to identify phosphopeptides generated from a trypsin digest of recombinant autophosphorylated ZAP-70, in particular with respect to quantifying the status at the regulatory phosphorylation sites Tyr-492 and Tyr-493. Combination of chromatographic and on-line tandem mass spectrometry data allowed one to ascertain the identity of the detected peptides, a prerequisite to analyses in more complex biological samples. As an extension to the methodology described above, we evaluated the feasibility of interfacing capillary HPLC to matrix assisted laser desorption ionisation time-of-flight mass spectrometry (MALDI-TOF-MS), using a micromachined piezoelectric flow-through dispenser as the interface. This enabled direct arraying of chromatographically separated components onto a target plate that was precoated with matrix for subsequent analysis by MALDI-TOF-MS without further sample handling.  相似文献   
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Objectives

Furocoumarins (psoralens and angelicins) have been already used under ultraviolet A light (UVA) for the treatment of skin diseases and cutaneous T‐cell lymphoma. Besides their high anti‐proliferative activity, some severe long‐term side effects have been observed, for example genotoxicity and mutagenicity, likely strictly related to the formation of crosslinks. It has been demonstrated that blue light (BL) activation of 8‐methoxypsoralen, an FDA‐approved drug, leads to less mutagenic monoadducts in the DNA. So far, in this work the less toxic and more penetrating BL is proposed to activate 4,6,4′‐trimethylangelicin (TMA), an already known UVA photoactivatable compound.

Materials and methods

Photocleavage, crosslink formation and oxidative damage were detected in pBR322 plasmid DNA treated with 300.0 μmol/L TMA activated with various exposures of BL. Anti‐proliferative activity, reactive oxygen species (ROS) formation and activation status of some signalling pathways involved in cell growth and apoptosis were verified on DU145 cells treated with 5.0 μmol/L TMA plus 2.0 J/cm2 of BL.

Results

Under BL‐TMA, no mutagenic crosslinks, no photocleavage and neither photooxidative lesions were detected on isolated plasmid DNA. TMA showed high anti‐proliferative activity on DU145 cells through induction of apoptosis. Besides ROS generation, the proapoptotic effect seemed to be related to activation of p38 and inhibition of p44/42 phosphorylation. Interestingly, the decrease in nuclear β‐catenin was coupled with a significant dropping of CD44‐positive cells.

Conclusion

Overall, our results indicate that TMA can be activated by BL and may be considered for targeted phototherapy of prostate cancer lesions.
  相似文献   
10.
The quillwort Isoëtes cangae is a critically endangered species occurring in a single lake in Serra dos Carajás, Eastern Amazon. Low genetic diversity and small effective population sizes (N e) are expected for narrow endemic species (NES). Conservation biology studies centered in a single species show some limitations, but they are still useful considering the limited time and resources available for protection of species at risk of extinction. Here, we evaluated the genetic diversity, population structure, N e, and minimum viable population (MVP) of Icangae to provide information for effective conservation programs. Our analyses were based on 55 individuals collected from the Amendoim Lake and 35,638 neutral SNPs. Our results indicated a single panmictic population, moderate levels of genetic diversity, and N e in the order of thousands, contrasting the expected for NES. Negative FIS values were also found, suggesting that Icangae is not under risk of inbreeding depression. Our findings imply that Icangae contains enough genetic diversity to ensure evolutionary potential and that all individuals should be treated as one demographic unit. These results provide essential information to optimize ex situ conservation efforts and genetic diversity monitoring, which are currently applied to guide Icangae conservation plans.  相似文献   
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