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61.
Peptidoglycan recognition proteins (PGRPs) are non-specific immune molecules of insects, and vertebrates etc., but are not present in plants and nematodes. In the current experiment, a PGRP DNA sequence (2,910 bp containing four exons) was identified from genomic DNA library of Asian corn borer, Ostrinia furnacalis, and a full-length cDNA programming PGRP was cloned (designed as OfPGRP-S) with an open reading frame of 579 bp, having 192 amino acid. This inferred amino acid sequence showed maximum similarity to known lepidopteran PGRPs. Quantitative real-time PCR investigation disclosed the level of mRNA of OfPGRP-S to be constitutively expressed in the whole developmental stages and with higher expression in the mature larvae. Even more the OfPGRP-S was mainly expressed in immune capable organs i.e., fat body and midgut, and was strongly induced by injecting gram-positive bacteria i.e., Staphylococus aureus. Recombinant protein OfPGRP-S could bind to S. aureus and Bacillus thuringiensis which enhance proPO activation in the presence of these microbes. The results indicated that OfPGRP-S is an inducible protein acting as a receptor-type PGRP for enhancing the proPO activation on exposure to bacteria.  相似文献   
62.
The objective of the present work was selection of cultivar and suitable medium for regenerating shoots from leaf segments of non-heading Chinese cabbage. We evaluated six types of supplemented media with 2.0, 5.0 and 10.0 mg l−1 6-BA; 1.0 and 2.0 mg l−1 TDZ; 0.1, 0.3, 0.5, 0.8 and 1.0 mg l−1NAA; 3.0, 5.0 and 7.5 mg l−1AgNO3; 0.01 mg l−1 2–4, D and 4.0 mg l−1 KT for shoot regeneration and six cultivars “Sanchidaye”, “Liuchuandasuomian”, “Qingyou 4”, “Liangbaiye”, “AiKang 5” and “Hanxiao F3”, furthermore for root formation three types of supplemented media with 0.2, 0.3, 0.5 mg l−1 NAA, and for survival rate two types of base media: turf + vermiculite + manure (1:2:0.2) and soil + vermiculite (1:2). Culturing leaf segments on MS medium supplemented with 2 mg l−1 TDZ; 0.5 mg l−1 NAA and 7.5 mg l−1 AgNO3 gave the highest number of shoots per leaf segment (66) while roots were best formed on the medium supplemented with 0.2 mg l−1 NAA. Survival rate was highest (61.6%) in the turf: vermiculite: manure (1:2:0.2) medium. The highest percentage of responding leaf segments, number of shoots per leaf segment, rooting percentage and survival rate were observed in “Liuchuandasuomian”. The plantlets were transferred to the soil and grown into mature plants in pots. These results could be used for preliminary selections of cultivars to transfer disease resistance (Bt) gene through agrobacterium in non-heading Chinese cabbage.  相似文献   
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Sclerotium rolfsii is one of the most destructive fungal plant pathogens that can infect over 500 plants and can adapt to diverse environmental conditions. The present research work was carried out to evaluate the impact of both hexa- and trivalent chromium (Cr) on growth, morphology, enzymatic characteristics, and metal accumulation in S. rolfsii under laboratory conditions. Experiments were performed in both malt extract broth and agar growth medium amended with six different concentrations (10, 20, 40, 60, 80, and 100 ppm) of each Cr(III) and Cr(VI) ions inoculated with fungus and incubated for 6–7 days at 25 ± 3 °C. In broth medium, the total protein content was declined and activities of antioxidant enzymes were increased with an increase in metal concentrations. Lower concentrations (10 ppm) of the metal ions stimulated the growth of fungus and higher concentrations (60–100) inhibited it. The Fourier transform infrared spectroscopy (FTIR) assessment showed hydroxyl, carboxyl, and amine groups as major metal binding sites. In agar medium, tolerance index was decreased up to 0.56 at 10–80 ppm of Cr(III) and up to 0.62 at 10–60 ppm of Cr(VI). Considerable modifications were observed in hyphal and sclerotial morphology with an increase in concentration of metal ions. The current study concluded that interference of Cr with growth and physiological process of S. rolfsii could affect its infection level on its host plant. This study provides important information regarding cultivation of susceptible plant varieties in Cr-polluted soil as evidenced by pathogen growth up to 50 ppm of Cr(III) and Cr(VI) ions.  相似文献   
66.

Objective

The objective of the study was to identify the occurrence and outcome of low back ache amongst computer users and their relation to age, gender, occupation and duration of computer use.

Materials and Methods

A self reported questionnaire tailored from Occupational Health and Safety Act of the Ministry of Labor, Ontario, Canada was used.

Results

416 participants 55.5% males and 45% females using computers for a minimum of five years with age range 22 to 59 years belonged to different occupational groups. Consecutive hours of computer work was found to be associated with work related backache or discomfort in 27.4% (n = 114) participants (16.1% male, 11.3% female). Frequent short breaks improved backache (p value <0.001) in 93 (22.4%) participants (13.2% male, 9.2% female). No significant relation was observed with the duration of computer usage or usage per day; between the two genders or occupational groups. Backache had no significance within age groups.

Conclusion

Our study identifies the occurrence of low back pain among those who are using computer for consecutive hours without breaks and the results suggest the need to create health awareness especially use of short breaks to minimize the risk and occurrence of low back pain. The result of this study can also be used to improve ergonomic design and standards.  相似文献   
67.
The common techniques to study protein-protein proximity in vivo are not well adapted to the capabilities and the expertise of a standard proteomics laboratory, typically based on the use of mass spectrometry. With the aim of closing this gap, we have developed PUB-MS (for proximity utilizing biotinylation and mass spectrometry), an approach to monitor protein-protein proximity, based on biotinylation of a protein fused to a biotin-acceptor peptide (BAP) by a biotin-ligase, BirA, fused to its interaction partner. The biotinylation status of the BAP can be further detected by either Western analysis or mass spectrometry. The BAP sequence was redesigned for easy monitoring of the biotinylation status by LC-MS/MS. In several experimental models, we demonstrate that the biotinylation in vivo is specifically enhanced when the BAP- and BirA-fused proteins are in proximity to each other. The advantage of mass spectrometry is demonstrated by using BAPs with different sequences in a single experiment (allowing multiplex analysis) and by the use of stable isotopes. Finally, we show that our methodology can be also used to study a specific subfraction of a protein of interest that was in proximity with another protein at a predefined time before the analysis.  相似文献   
68.
3-Formylchromone (1), 3-methyl-7-hydroxychromone (2) and Schiff bases of 3-formylchromone 319 have been synthesized and their anti-thymidine phosphorylase inhibitory activity was evaluated. Compounds 119 showed a varying degree of thymidine phosphorylase inhibition with IC50 values 19.77 ± 3.25 to 480.21 ± 2.34 μM. Their activity was compared with the standard 7-deazaxanthine (IC50 = 39.28 ± 0.76 μM). Compound 12 showed an excellent thymidine phosphorylase inhibitory activity with an IC50 value of 19.77 ± 3.25 μM, better than the standard. Compound 4 also showed an excellent inhibitory activity (IC50 = 40.29 ± 4.56 μM). The parent 3-formylchromone (1) and 3-methyl-7-hydroxychromone (2) were found to be inactive. The structures of the compounds were elucidated by using spectroscopic techniques, including 1H NMR, EI MS, IR, UV and elemental analysis.  相似文献   
69.
6-Nitrobenzimidazole derivatives (1-30) synthesized and their phosphodiesterase inhibitory activities determined. Out of thirty tested compounds, ten showed a varying degrees of phosphodiesterase inhibition with IC(50) values between 1.5±0.043 and 294.0±16.7 μM. Compounds 30 (IC(50)=1.5±0.043 μM), 1 (IC(50)=2.4±0.049 μM), 11 (IC(50)=5.7±0.113 μM), 13 (IC(50)=6.4±0.148 μM), 14 (IC(50)=10.5±0.51 μM), 9 (IC(50)=11.49±0.08 μM), 3 (IC(50)=63.1±1.48 μM), 10 (IC(50)=120.0±4.47 μM), and 6 (IC(50)=153.2±5.6 μM) showed excellent phosphodiesterase inhibitory activity, much superior to the standard EDTA (IC(50)=274±0.007 μM), and thus are potential molecules for the development of a new class of phosphodiesterase inhibitors. A structure-activity relationship is evaluated. All compounds are characterized by spectroscopic parameters.  相似文献   
70.
Owing to their potential applications,as well as their structural diversity,the discovery of novel secondary metabolites from insect-associated fungi has been of interest to researchers in recent years.The aim of this study was therefore to estimate the diversity of fungi associated with fungus-growing termites and bioprospecting these for potential secondary metabolites.In total,18 fungal species were isolated and described from the gut and comb of Macrotermes barneyi based on 18S ribosomal DNA gene sequence analysis.Antimicrobial activity assays were carried out on all the known fungi,and nine isolates were recorded as active against pathogenic fungi.Xylaria escharoidea,the best performing isolate,was grown at laboratory scale and 4,8-dihydroxy-3,4-dihydronaphthalen-l(2H)was isolated and characterized.The minimum inhibitory concentration of this isolated compound against tested pathogenic organisms was found to be 6.25 fig.In addition,molecular docking studies have revealed that 4,8-dihydroxy-3,4-dihydronaphthalen-l(2H)is a prominent antibacterial agent with a marked interaction with key residues on protein A(agrAc)that regulates the accessory gene.The findings of this study support the drug discovery of antimicrobial properties in insect-associated fungi,which may lead to novel secondary metabolites.  相似文献   
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