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101.
Aphis fabae Scopoli (Hemiptera: Aphididae) is heteroecious and polyphagous that is harmful on secondary hosts such as many important agricultural products like beet, common bean, faba bean, potato and other products. This aphid is the cause of more than 33 viral transition. One of the mechanisms of plant resistance is antixenosis. This mechanism influences on placement and nutrition of pests that result in less damage. In this study, antixenosis resistance mechanism of 12 varieties of bean was tested. Experiment was on completely randomised design with 12 treatments and 6 replications. Bean varieties include of white bean, kidney bean and wax bean, and each replication includes one pot, and then, pots were placed under the isolated room that were filled with winged adult aphids in circular form. After 24 and 48?h, aphids and level of nymph production were counted. The lowest number of adult aphids was observed on Sayad variety among 12 varieties (during 24?h). The least number of produced nymphs was in Daneshkade variety. In Sayad variety, the frequency of matured insects and produced nymphs was minimum.  相似文献   
102.
The necrotrophic fungus Botrytis cinerea is reported to infect more than 220 host plants worldwide. In phylogenetical–taxonomical terms, the pathogen is considered a complex of two cryptic species, group I and group II. We sampled populations of B. cinerea on sympatric strawberry and raspberry cultivars in the North-East of Hungary for three years during flowering and the harvest period. Four hundred and ninety group II B. cinerea isolates were analyzed for the current study. Three different data sets were generated: (i) PCR-RFLP patterns of the ADP-ATP translocase and nitrate reductase genes, (ii) MSB1 minisatellite sequence data, and (iii) the fragment sizes of five microsatellite loci. The structures of the different populations were similar as indicated by Nei's gene diversity and haplotype diversity. The F statistics (Fst, Gst), and the gene flow indicated ongoing differentiation within sympatric populations. The population genetic parameters were influenced by polymorphisms within the three data sets as assessed using Bayesian algorithms. Data Mining analysis pointed towards the five microsatellite loci as the most defining markers to study differentiation in the 490 isolates. The results suggest the occurrence of host-specific, sympatric divergence of generalist phytoparasites in perennial hosts.  相似文献   
103.

Background

Meta-analyses conducted via the Cochrane Collaboration adhere to strict methodological and reporting standards aiming to minimize bias, maximize transparency/reproducibility, and improve the accuracy of summarized data. Whether this results in differences in the results reported by meta-analyses on the same topic conducted outside the Cochrane Collaboration is an open question.

Methods

We conducted a matched-pair analysis with individual meta-analyses as the unit of analysis, comparing Cochrane and non-Cochrane reviews. Using meta-analyses from the cardiovascular literature, we identified pairs that matched on intervention and outcome. The pairs were contrasted in terms of how frequently results disagreed between the Cochrane and non-Cochrane reviews, whether effect sizes and statistical precision differed systematically, and how these differences related to the frequency of secondary citations of those reviews.

Results

Our search yielded 40 matched pairs of reviews. The two sets were similar in terms of which was first to publication, how many studies were included, and average sample sizes. The paired reviews included a total of 344 individual clinical trials: 111 (32.3%) studies were included only in a Cochrane review, 104 (30.2%) only in a non-Cochrane review, and 129 (37.5%) in both. Stated another way, 62.5% of studies were only included in one or the other meta-analytic literature. Overall, 37.5% of pairs had discrepant results. The most common involved shifts in the width of 95% confidence intervals that would yield a different statistical interpretation of the significance of results (7 pairs). Additionally, 20% differed in the direction of the summary effect size (5 pairs) or reported greater than a 2-fold difference in its magnitude (3 pairs). Non-Cochrane reviews reported significantly higher effect sizes (P< 0.001) and lower precision (P<0.001) than matched Cochrane reviews. Reviews reporting an effect size at least 2-fold greater than their matched pair were cited more frequently.

Conclusion

Though results between topic-matched Cochrane and non-Cochrane reviews were quite similar, discrepant results were frequent, and the overlap of included studies was surprisingly low. Non-Cochrane reviews report larger effect sizes with lower precision than Cochrane reviews, indicating systematic differences, likely reflective of methodology, between the two types of reviews that could generate different interpretations of the interventions under question.  相似文献   
104.
The biological traits of the entomopathogenic nematodes (EPNs), Steinernema carpocapsae and Heterorhabditis bacteriophora, against the larvae of the leopard moth, Zeuzera pyrina were evaluated in the laboratory. The traits included pathogenicity, penetration potential as well as foraging behaviour. Plate assays were performed using a range of EPN concentrations (5, 10, 20, 50 and 100 infective juveniles (IJs) per larva). The LC50 values for S. carpocapsae and H. bacteriophora were 6.4 and 8.4 IJs larva?1 after 72 h. Both EPN species caused high mortality in branch experiments. Significantly higher mortality rates occurred in the larger larvae after exposure to S. carpocapsae. Both EPN species successfully penetrated the Z. pyrina larvae as well as larvae of Galleria mellonella L. (Lepidoptera: Galleridae).The proportional response of H. bacteriophora to host-associated cues was strongly higher than S. carpocapsae in Petri dishes containing agar 1, 12 and 24 h after EPN application. These results highlight the efficiency of EPNs for the control of Z. pyrina larvae. However, due to the cryptic habitat of Z. pyrina larvae in their galleries in the trees, field trails need to be conducted to further evaluate this potential.  相似文献   
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107.
A simple high-performance liquid chromatographic method for simultaneous determination of ethylenediaminetetraacetic acid (EDTA), sorbic acid, and diclofenac sodium was developed and validated. Separation was achieved on a C18 column (10 cm × 4.6 mm) using gradient elution. The mobile phase consisted of acetonitrile–ammonium dihydrogen phosphate buffer solution (0.01 M, pH = 2.5, containing 0.8% tetra-n-butyl ammonium hydroxide). The detector wavelength was set at 254 nm. Under these conditions, separation of three compounds was achieved in less than 10 min. The effect of two metal salts and metal concentration on peak area of EDTA was investigated. The pH effect on retention of EDTA and sorbic acid was studied. The method showed linearity for EDTA, sorbic acid, and diclofenac in the ranges of 2.5–100.0, 5.0–200.0, and 20.0–120.0 μg/mL, respectively. The within- and between-day relative standard deviations ranged from 0.52 to 1.94%, 0.50 to 1.34%, and 0.78 to 1.67% for EDTA, sorbic acid, and diclofenac, respectively. The recovery of EDTA, sorbic acid, and diclofenac from pharmaceutical preparation ranged from 96.0–102.0%, 99.7–101.5%, to 97.0–102.5%, respectively. To the best of our knowledge, this is the first report about simultaneous determination of EDTA, sorbic acid, and diclofenac.KEY WORDS: diclofenac sodium, EDTA, high-performance liquid chromatography, pharmaceutical preparations, sorbic acid  相似文献   
108.
Shigella is known as pathogenic intestinal bacteria in high dispersion and pathogenic bacteria due to invasive plasmid antigen (Ipa). So far, a number of Ipa proteins have been studied to introduce a new candidate vaccine. Here, for the first time, we examined whether the N-terminal region of IpaD72–162 could be a proper candidate for Shigella vaccine. Initially, the DNA sequence coding N-terminal region was isolated by PCR from Shigella dysenteriae type I and cloned into pET-28a expression vector. Then, the heterologous protein was expressed, optimized and purified by affinity Ni–NTA column. Western blot analysis using, His-tag and IpaD72–162 polyclonal antibodies, confirmed the purity and specificity of the recombinant protein, respectively. Subsequently, the high immunogenicity of the antigen was shown by ELISA. The results of the sereny test in Guinea pigs showed that IpaD72–162 provides a protective system against Shigella flexneri 5a and S. dysenteriae type I.  相似文献   
109.
Molecular Biology Reports - This study aimed to investigate the occurrence of Legionella species in the respiratory samples of patients with pneumonia symptoms from Ahvaz, Iran by culture and the...  相似文献   
110.
Molecular Biology Reports - Evidence has validated the prophylactic effects of exercising on different aspects of health. On the opposite side, immobilization may lead to various destructive...  相似文献   
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