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421.
Seed storage proteins of ten maize inbred lines were investigated by sodium dodecyl sulfate polyacrylamide gel electrophoresis. In addition, fourteen isozyme loci representing nine isozyme systems were analysed. Salt-soluble protein fraction contained a large number of proteins (30 – 40 bands) of different sizes with genotypic differences among the ten inbred lines. The methionine-rich 10 kD zein showed differential expression in the ten inbred lines with different migration rates on the SDS-PAGE. This polypeptide was completely absent in the inbred line G221D. Among nine of the inbred lines, eight of 14 isozyme loci were polymorphic and six were monomorphic resulting in seven unique fingerprints.  相似文献   
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A plausible hypothesis as to the mode of action of dexamethasone (DXM) has been proposed. Growth of irradiated tadpoles of Bufo melanostictus, treated daily with the corticoid, is more suppressed. Compared with its antagonism with ACTH, its coordinate promotion of TSH production accelerates metamorphosis. This modulated feedback is consistent with the constant course of the hypothalamic nuclei influence upon the adenohypophyseal hormones.  相似文献   
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Here, a simple and portable paper-based analytical device (PAD) based on the inherent capability of carbon quantum dots (CQDs) to serve as a great emitter for the bis(2,4,6-trichlorophenyl)oxalate (TCPO)–hydrogen peroxide (H₂O₂) chemiluminescence (CL) reaction is introduced for the detection of harmful mercury ions (Hg2+). The energy is transferred from the unstable reaction intermediate (1,2-dioxetanedione) to CQDs, as acceptors, and an intensive orange-red CL emission is generated at ~600 nm, which is equal to the fluorescence emission wavelength of CQDs. The analytical applicability of this system was examined for the determination of Hg2+. It was observed that Hg2+ could significantly quench the produced emission, which can be attributed to the formation of a stable and nonluminescent Hg2+–CQDs complex. Accordingly, a simple and rapid PAD was established for monitoring Hg2+, with a limit of detection of 0.04 μg ml−1. No interfering effect on the signal was found from other examined cations, indicating the acceptable specificity of the method. The designed assay was appropriately utilized to detect Hg2+ ions in cosmetic samples with high efficiency. It was characterized by its low cost, ease of use, and was facile but accurate and high selective for the detection of Hg2+ ions. In addition, the portability of this probe makes it suitable for on-site screening purposes.  相似文献   
426.

Since the 19th century to date, the fungal pathogens have been involved in causing devastating diseases in plants. All types of fungal pathogens have been observed in important agricultural crops that lead to significant pre and postharvest losses. The application of synthetic fungicide against the fungal plant pathogens (FPP) is a traditional management practice but at the same time these fungicides kill other beneficial microbes, insects, animal, and humans and are harmful to environment. The antagonistic microorganism such as bacteria are being used as an alternate strategy to control the FPP. These antagonistic species are cost-effective and eco-friendly in nature. These biocontrol bacteria have a broad mechanism against fungal pathogens present in the phyllosphere and rhizosphere of the plant. The antagonistic bacteria have different strategies against the FPP, by producing siderophore, biofilm, volatile organic compounds (VOCs), through parasitism, antibiosis, competition for limited resources and induce systemic resistance (ISR) in the host plant by activating the immune systems. The commercial bio-products synthesized by the major bacterial species Pseudomonas syringae, Burkholderia cepacia, Streptomyces griseoviridis, Pseudomonas fluorescens and Bacillus subtilis are used to control Fusarium, Pythium, Rhizoctonia, Penicillium, Alternaria, and Geotrichum. The commercial bio-formulations of bacteria act as both antifungal and plant growth regulators. The Plant growth-promoting rhizobacteria (PGPR) played a significant role in improving plant health by nitrogen-fixing, phosphorus solubilization, phytohormones production, minimizing soil metal contamination, and by ACC deaminase antifungal activities. Different articles are available on the specific antifungal activity of bacteria in plant diseases. Therefore, this review article has summarized the information on biocontrol activity of bacteria against the FPP and the role of PGPR in plant growth promotion. This review also provided a complete picture of scattered information regarding antifungal activities of bacteria and the role of PGPR.

  相似文献   
427.
Modeling sensitivity to drugs based on genetic characterizations is a significant challenge in the area of systems medicine. Ensemble based approaches such as Random Forests have been shown to perform well in both individual sensitivity prediction studies and team science based prediction challenges. However, Random Forests generate a deterministic predictive model for each drug based on the genetic characterization of the cell lines and ignores the relationship between different drug sensitivities during model generation. This application motivates the need for generation of multivariate ensemble learning techniques that can increase prediction accuracy and improve variable importance ranking by incorporating the relationships between different output responses. In this article, we propose a novel cost criterion that captures the dissimilarity in the output response structure between the training data and node samples as the difference in the two empirical copulas. We illustrate that copulas are suitable for capturing the multivariate structure of output responses independent of the marginal distributions and the copula based multivariate random forest framework can provide higher accuracy prediction and improved variable selection. The proposed framework has been validated on genomics of drug sensitivity for cancer and cancer cell line encyclopedia database.  相似文献   
428.
Since the first publication regarding the existence of stem cells in cancer [cancer stem cells(CSCs)] in 1994, many studies have been published providing in-depth information about their biology and function. This research has paved the way in terms of appreciating the role of CSCs in tumour aggressiveness, progression,recurrence and resistance to cancer therapy. Targeting CSCs for cancer therapy has still not progressed to a sufficient degree, particularly in terms of exploring the mechanism of dynamic interconversion between CSCs and non-CSCs. Besides the CSC scenario, the problem of cancer dissemination has been analyzed indepth with the identification and isolation of microRNAs(miRs), which are now considered to be compelling molecular markers in the diagnosis and prognosis of tumours in general and specifically in patients with non-small cell lung cancer.Paracrine release of miRs via "exosomes"(small membrane vesicles(30-100 nm),the derivation of which lies in the luminal membranes of multi-vesicular bodies)released by fusion with the cell membrane is gaining popularity. Whether exosomes play a significant role in maintaining a dynamic equilibrium state between CSCs and non-CSCs and their mechanism of activity is as yet unknown.Future studies on CSC-related exosomes will provide new perspectives for precision-targeted treatment strategies.  相似文献   
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The experiment was conducted at Cotton Research Station, Multan to study the impact of weather factors and Hemipterous bug on development of cotton boll disease in cotton variety bt- 886 for three consecutive years i.e., 2012, 2013 and 2014. The results revealed that the population of Red Cotton Bug (RCB) per plant remain 0.50 and 0.34 during years 2012 and 2013, respectively but increased during 2014 i.e., 3.21 per plant. The number of unopened bolls (UOB) were more during 2012 i.e., 13.43% with yellowish lint (YL) 76.30% and whitish lint (WL) 23.70% at average maximum temperature of 34.73◦C, minimum temperature of 22.83◦C, RH of 77.43% and 11.08 mm rainfall. Similarly during 2013, the number of unopened bolls were less i.e., 0.34 per plant with YL 1.48 and WL 99.53 per plant when average maximum temperature 34.60C, minimum temperature 23.37C, RH 73.01% and 9.95 mm rainfall. During 2014, RCB population per plant was 3.22 with no UOB and YL was 0.00% and WL was 100% when average maximum temperature 23.70C, minimum temperature 23.18◦C, RH 71.67% and 4.55 mm rainfall. So our results concluded that the cotton bolls rot disease was more during 2012 due to abrupt changes in environmental factors. The RCB may be the carrier of boll rot disease pathogen during more rainfall.  相似文献   
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