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101.
Carboxylic acids play an important role in both aerobic and anaerobic metabolic pathways of both the snail and the parasite. Monitoring the effects of infection by schistosome on Biomphalaria alexandrina carboxylic acids metabolic profiles represents a promising additional source of information about the state of metabolic system. We separated and quantified pyruvic, fumaric, malic, oxalic, and acetic acids using ion-suppression reversed-phase high performance liquid chromatography (HPLC) to detect correlations between these acids in both hemolymph and digestive gland gonad complex (DGG's) samples in a total of 300 B. alexandrina snails (150 infected and 150 controls) at different stages of infection. The results showed that the majority of metabolite pairs did not show significant correlations. However, some high correlations were found between the studied acids within the control group but not in other groups. More striking was the existence of reversed correlations between the same acids at different stages of infection. Some possible explanations of the underlying mechanisms were discussed. Ultimately, however, further data are required for resolving the responsible regulatory events. These findings highlight the potential of metabolomics as a novel approach for fundamental investigations of host-pathogen interactions as well as disease surveillance and control.  相似文献   
102.
A novel series of cationic surfactants was prepared based on Mannich base (produced from the condensation of piperidine and/or morpholine as secondary amine and paraformaldehyde in the presence of 8-hydroxyquinoline). The chemical structures of the synthesized cationic surfactants were confirmed using elemental analyses, FTIR spectroscopy and 1H NMR. Surface activities of the prepared surfactants were measured including: surface tension (gamma), critical micelle concentration (CMC), effectiveness (pi(CMC)), efficiency (Pc20), maximum surface excess (Gamma(max)), minimum surface area (A(min)), interfacial tension (gamma(IT)), emulsification power and foaming power at 25 degrees C. The structural influences on their surface activities and adsorption free energy were discussed. The synthesized cationic surfactants were evaluated for their biocidal activity towards Gram +ve bacteria (Staph. Cocu., Bacillus), Gram -ve bacteria (Salmonella, E. coli), fungi (A. terrus., A. flav.) and yeast (Candida) at 1.0, 2.5 and 5.0mg/mL, respectively. The target compounds showed good inhibition towards Gram +ve bacteria, Gram -ve bacteria and yeast. Meanwhile, excellent fungicidal results were obtained against the various types of fungi under investigation.  相似文献   
103.
Most autoimmune disease are driven by a dysfunction in T and B cells, but B cells are still an interesting area of research, perturbations in their development are implicated in autoimmune diseases. B cell differentiating factor (BCDF) plays a part in the differentiation of B cells. The aim was To assess the levels of BCDF, IgM and IgG in SLE patients and whether they have any peculiarity in the clinical context of SLE. Thirty six patients with SLE and 24 healthy volunteers as control were enrolled in the study. BCDF was measured using Sandwich ELISA, total human IgM and IgG were measured by calorimetric methods. The mean concentrations of BCDF and IgM were significantly higher in patients with SLE as compared with controls (P?<?0.001 and P?<?0.0001 respectively). No significant difference was observed as regard IgG. We observed positive correlation between BCDF and IgM (r?=?0.281, P?=?0.03), and between IgG and IgM, duration of the disease (r?=?0.468, P?=?0.004, r?=?0.337, P?=?0.008 respectively). Moreover we observed lower IgM level in patients with discoid lesion (P?=?0.009) and lower IgG level in those with hematologic manifestations (P?=?0.02). ROC analysis revealed area under curve (AUC) 0.861 for BCDF and 0.902 for IgM, they can delineate SLE from controls at a cut-off value of 98.5?pg/ml, and 18?mg/dl IgM respectively.

Conclusion

BCDF and IgM are increased in SLE patients and are promissing diagnostic markers for SLE.  相似文献   
104.
Abiotic stresses present a real environmental problem in agriculture field. In our paper, we examine the significance of arbuscular mycorrhizal fungi (AMF) and soil amendment with water retaining superpolymers (hydrogel) on growth and physiology performance of olive plantlets. Our experiment was carried out in nursery conditions, to test the impact of hydrogel (TH) and mycorrhizal fungi (TM), used individually or combined (THM), and compare them with non inoculated plants (TC), to understand and reduce the water stress damage in olive plantlets (cv. Chemlali). We also evaluate interactions between hydrogel, mycorrhizal treatments and water regimes. Results of mycorrhization (M%) show that roots colonized by Rhizophagus irregularis of well-watered plants were about 40.87%. In combined treatment (THM), M% was about 32.14%. Compared to TC treatment, TM treatment enhances significantly the dry weights of the whole plant under the two water regimes. The TM treatment had the highest relative water content (66.50%) and Chl (a?+?b) (0.83 mg g??1) in stressed conditions. We found also that under water stress, the maximal quantum efficiency of the photosystem II measurements in leaves were significantly improved by 50.70% in TH treatment compared to control. For phenolic contents, TH treatment decreased significantly total phenols by 50.10% compared to TC. Our study gives evidence that the use of AMF and the hydrogel separately or in combination may enhance the capacity to avoid drought damages of olive plantlets and improve olive performances.  相似文献   
105.
Six flavonoid glycosides: quercetin 3-glucoside, quercetin-3-rutinoside; 3-glucoside, 3-rutinoside, 3-7-diglucoside and 3-rhamnogalactoside of isorhamnetin were extracted and identified from the leaves and branches of Egyptian material ofBalanites aegyptiaca. Only isorhamnetin: 3-rutinoside and 3-rhamnogalactoside were recorded from the fruits of the same plant.—Phytochemical aspects ofBalanites aegyptiaca and some genera ofZygophylaceae s. l. viz.Nitraria, Fagonia, Zygophyllum, Seetzenia andTribulus support its affinities with that family.  相似文献   
106.
Plant growth promoting bacteria (PGPB) may help to reduce the toxicity of heavy metals on plants growing in polluted soils. In this work, Sulla coronaria inoculated with four Cd resistant bacteria (two Pseudomonas spp. and two Rhizobium sullae) were cultivated in hydroponic conditions treated by Cd; long time treatment 50 µM CdCl2 for 30 days and short time treatment; 100 µM CdCl2 for 7 days. Results showed that inoculation with Cd resistant PGPB enhanced plant biomass, thus shoot and root dry weights of control plants were enhanced by 148 and 35% respectively after 7 days. Co-inoculation of plants treated with 50 and 100 µM Cd increased plant biomasses as compared to Cd-treated and uninoculated plants. Cadmium treatment induced lipid peroxidation in plant tissues measured through MDA content in short 7 days 100 µM treatment. Antioxidant enzyme studies showed that inoculation of control plants enhanced APX, SOD and CAT activities after 30 days in shoots and SOD, APX, SOD, GPOX in roots. Application of 50 µM CdCl2 stimulated all enzymes in shoots and decreased SOD and CAT activities in roots. Moreover, 100 µM of CdCl2 increased SOD, APX, CAT and GPOX activities in shoots and increased significantly CAT activity in roots. Metal accumulation depended on Cd concentration, plant organ and time of treatment. Furthermore, the inoculation enhanced Cd uptake in roots by 20% in all treatments. The cultivation of this symbiosis in Cd contaminated soil or in heavy metal hydroponically treated medium, showed that inoculation improved plant biomass and increased Cd uptake especially in roots. Therefore, the present study established that co-inoculation of S. coronaria by a specific consortium of heavy metal resistant PGPB formed a symbiotic system useful for soil phytostabilization.  相似文献   
107.
Technical limitations are associated with conducting successful in situ hybridization. In this study, three cell types including a tumor neuroblastoma cell line (Neuro-2a), an oligodendrocyte primary culture, and a nonneuronal acute lymphoblastic leukemia cell line (Reh) were used to conduct successful nonradioactive in situ hybridization. Two cDNA probes were used. A 1 kb probe was used to identify the expression of proteolipid protein (PLP) mRNA in a primary culture of oligodendrocytes. A 760 bp cDNA was used to identify the expression of ubiquitin C-terminal hydrolase (UCH-L1) mRNA in Neuro-2a and Reh cells. The probes were labeled with digoxigenin-11-dUTP, denatured, and hybridized with cells fixed on coverslips. The efficiency of the labeling was tested using dot blot analysis by comparing the intensity of our labeled probes with known concentration of the probe labeled by the provider. The nonspecific signals were washed off, followed by detection of a signal specific to the gene. The specificity of the probes was determined by treating the cells with RNase A, hybridizing with bacterial Dig-labeled cDNA (pBR322) and hybridizing the tissues in the absence of labeled probe. During the labeling step, we found that addition of co-precipitants, such as tRNA or glycogen, during precipitation of the labeled probe followed by overnight incubation at -20 C is essential for good recovery of labeled cDNA. Dissolving the labeled probe in a buffer solution containing sodium dodecyl sulfate improves the quantity of the labeling. At the cellular level, prehybridization treatments optimize the permeability of the cell and allow efficient penetration of the labeled probe. Fixing with paraformaldehyde or an ethanol-acetic acid mixture can preserve the structure of cultured cells. To increase the signal to noise ratio, cells were treated with 0.2 N HC1 followed by extensive washes using a solution with a high salt concentration and containing dextran sulfate. This treatment significantly improves the signal and reduces the background in cell cultures, but not in tissue sections. The ability to reuse the labeled probe-hybridization mixture is another advantage for using nonradioactive in situ hybridization.  相似文献   
108.
The plasmid profile of two thermophilic bacterial strains isolated from recreation thermal springs in Jordan has been investigated. These strains are Streptococcus thermophilus and Bacillus sp1, which have been isolated from Zerka – Maeen and Himma hot springs respectively. Supercoiled and circular plasmid forms were detected, explaining the effect of DNA conformation on the mobility of the plasmid in the agarose gel electrophoresis. Two plasmids have been isolated and characterized by restriction endonucleases to facilitate their use as cloning vectors in thermophilic strains. The sizes of the plasmids were approximately 3 kb (from Streptococcus thermophilus) and 7 kb (from Bacillus spl). These plasmids were then digested with three different restriction enzymes (EcoRI, Bam HI, and HindIII), one of which was found to possess a single site for both plasmids, this enzyme is EcoRI.  相似文献   
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