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1.
Environmental factors affecting essential oils variability in Thymus piperella L. are studied. The relationship between the bioclimatics index and edaphic factors with three chemotypes is determined through the application of multivariate analysis (CANOCO) and other statistical processes to both ecological and the essential oil data set components. Chemotype p-cymene γ-terpinene carvacrol shows a positive relationship with the aridity index (Ia) and Altitude. The p-cymene thymol chemotype is related to factors affecting water balance in both the soils and plants. The influence of climatic factors over p-cymene carvacrol is less evident. The compound p-cymene, common to the three chemical groups and the most abundant of all, presents positive correlation with the organic matter in the soil.  相似文献   
2.
Essential oil (EO) extracts coming from two representative populations of Mentha suaveolens Ehrh . subesp. suaveolens in Eastern Iberian Peninsula were analyzed by gas chromatography coupled with mass spectrometry and flame ion detector. Plant sampling was carried out in the morning and evening in order to study diurnal variation in EO profiles. Likewise, leaves and inflorescences were analyzed separately. Two chemotypes corresponding to each one of the populations were identified, with piperitenone oxide (35.2 – 74.3%) and piperitone oxide (83.9 – 91.3%), respectively, as major compounds. Once different chemotypes were identified, canonical correspondence analysis was employed to evaluate the effect of the bioclimatic and edaphic factors recorded in each location on the observed differences. Statistical analysis suggested that these chemotypes were closely related to specific environmental factors, mainly the bioclimatic ones. Concretely, piperitenone oxide chemotype can be associated to supramediterranean bioclimatic conditions and soils with major salinity and water field capacity. On the other hand, the most volatile fraction (hydrocarbon monoterpenes) reached its higher level in the morning; specifically, a noticeable amount of limonene was found in morning samples of flowers (4.8 – 10.6%). This fact can be related to ecological role of volatile compounds in order to attract pollinator insects.  相似文献   
3.
The essential oil composition of Lantana camara, Eucalyptus camaldulensis and Eriocephalus africanus was analyzed by means of GC and GC–MS and bioassayed in order to determine their activity against Amaranthus hybridus and Portulaca oleracea. E. camaldulensis essential oil, with spathulenol as the main compound, was the most effective, completely inhibiting germination and seedling growth on both weeds. The essential oil of E. africanus, rich in artemisia ketone, showed activity similar to that of E. camaldulensis on A. hybridus, but it was not so effective against P. oleracea, and L. camara essential oil, with high percentages in sesquiterpene hydrocarbons, also showed higher phytotoxic activity against A. hybridus, inhibiting its germination and seedling length; however, it showed no effect against P. oleracea germination, whereas was effective in significantly reducing its seedling growth at all concentrations assayed. The results suggest the possible use of these essential oils as natural herbicides.  相似文献   
4.
The relative efficiency of a reduced index (IR) relative to a full index (IF) was compared in an experiment with Tribolium. The selection objective included pupal length, adult weight, and egg mass. The reduced index was based on pupal length and adult weight, whereas the full index was based on these traits and also on egg mass. There were five generations of selection with four replicates, and a selected proportion of 20%. For each replicate, an unselected control was produced. Responses were significant in the IF and IR lines. Responses for the selection objective differed significantly between lines (p < 0.01). The efficiency of the IR line relative to the IF line was 0.52, similar to the expected efficiency of 0.51. The IF and IR lines did not differ significantly for pupal length nor adult weight, whereas the response for egg mass in the IF line was significantly different from the response in the IR line. Realized heritability was greater in the IF line (0.63 ± 0.05) than in the IR line (0.37 ± 0.16). The deleted trait (egg mass) has high heritability and genetic and phenotypic correlations nearly equal to zero with the other two traits included in the selection criterion. The results show the importance of including index traits with high genetic value that are independent of other traits, and they could be useful in breeding programs simultaneously considering production and reproduction traits with nearly zero correlations between them.  相似文献   
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Planta - Transgenic papaya callus lines expressing the components of the S3Pvac vaccine constitute a stable platform to produce an oral vaccine against cysticercosis caused by Taenia solium or T....  相似文献   
7.
Toll-like receptors trigger the innate immune response by activating various cell types such us macrophages and lymphocytes. We genotyped SNV of TLR3, TRL7, TLR8 and TLR10 in 863 Spanish and 150 Italian patients with Meniere’s disease (MD) and 1,013 controls by using Taqman assays. Real-Time qPCR was used to measure the expression level of TLR10 in peripheral blood leukocytes. The overall dataset showed that the C allele and the CC genotype of rs11096955 in TLR10 gene were more commonly observed in controls than patients (corrected p?=?1?×?10?3, OR?=?0.68 [95 % confidence interval, 0.54–0.84] for CC genotype; corrected p?=?1.5?×?10?5, OR?=?0.75 [0.66–0.85] for allele C). Moreover, the CC genotype was more frequent in patients with uni- (19 %) than bilateral sensorineural hearing loss (SNHL) (13 %). Logistic regression demonstrated that the time since the onset of MD, Tumarkin crises, hearing stage and rs11096955 were independent factors influencing the risk of bilateral SNHL. In addition, rs11096955 influenced hearing loss progression in patients with bilateral MD. No change in expression of TLR10 was observed according to CC, CA or AA genotypes. Our data suggest that allelic variants of TLR10 gene may influence the susceptibility and time-course of hearing loss of MD in the European population.  相似文献   
8.

Background

Autoimmunity appears to be associated with the pathophysiology of Meniere''s disease (MD), an inner ear disorder characterized by episodes of vertigo associated with hearing loss and tinnitus. However, the prevalence of autoimmune diseases (AD) in patients with MD has not been studied in individuals with uni or bilateral sensorineural hearing loss (SNHL).

Methods and Findings

We estimated the prevalence of AD in 690 outpatients with MD with uni or bilateral SNHL from otoneurology clinics at six tertiary referral hospitals by using clinica criteria and an immune panel (lymphocyte populations, antinuclear antibodies, C3, C4 and proinflammatory cytokines TNFα, INFγ). The observed prevalence of rheumatoid arthritis (RA), systemic lupus erythematosus (SLE) and ankylosing spondylitis (AS) was higher than expected for the general population (1.39 for RA, 0.87 for SLE and 0.70 for AS, respectively). Systemic AD were more frequently observed in patients with MD and diagnostic criteria for migraine than cases with MD and tension-type headache (p = 0.007). There were clinical differences between patients with uni or bilateral SNHL, but no differences were found in the immune profile. Multiple linear regression showed that changes in lymphocytes subpopulations were associated with hearing loss and persistence of vertigo, suggesting a role for the immune response in MD.

Conclusions

Despite some limitations, MD displays an elevated prevalence of systemic AD such as RA, SLE and AS. This finding, which suggests an autoimmune background in a subset of patients with MD, has important implications for the treatment of MD.  相似文献   
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10.
The aim of this work is to prepare tretinoin/dimethyl-beta-cyclodextrin complexes and fully characterize them through various analytical techniques. According to the phase solubility studies performed, the equilibrium for maximum complexation is reached in about 8 days presenting an AL-type diagram (soluble complexes) corresponding mainly to 1:1 stoichiometry (K s = 13,600 M−1), although the possibility of the presence of 1:2 complexes was mathematically proven. Differential scanning calorimetry, X-ray diffraction and all the other analytical techniques have proven the presence of true complex formation in all the preparation methods tested. H-NMR and FTIR spectra allowed the selection of the best complexation method. The comparison between Raman spectra revealed that the more relevant feature is the band at 1,573 cm−1, which corresponds to the entire delocalization of the superconjugated system, and after inclusion is observed as a positive frequency shift. Based on these results and the data obtained by molecular modelling calculations, it is proposed that the structure of the drug included into the cyclodextrin corresponds to the side chain including the functional group COOH. The complex was also analysed by atomic force microscopy to determine its size distribution which was heterogeneous and polymodal. However, it could be observed that they all have the same phase constitution.  相似文献   
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