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排序方式: 共有1718条查询结果,搜索用时 15 毫秒
41.
An overview of sustainability assessment methodologies 总被引:3,自引:0,他引:3
Sustainability indicators and composite index are increasingly recognised as a useful tool for policy making and public communication in conveying information on countries and corporate performance in fields such as environment, economy, society, or technological improvement. By visualizing phenomena and highlighting trends, sustainability indicators simplify, quantify, analyse and communicate otherwise complex and complicated information.There are number of initiatives working on indicators and frameworks for sustainable development (SD). This article provides an overview various sustainability indices applied in policy practice. The paper also compiles the information related to sustainability indices formulation strategy, scaling, normalisation, weighting and aggregation methodology. 相似文献
42.
Aaron M Gruver Brian D Yard Campbell McInnes Changanamkandath Rajesh Douglas L Pittman 《BMC molecular biology》2009,10(1):27
Background
The homologous recombination (HR) pathway is vital for maintaining genomic integrity through the restoration of double-stranded breaks and interstrand crosslinks. The RAD51 paralogs (RAD51B, RAD51C, RAD51D, XRCC2, XRCC3) are essential for this process in vertebrates, and the RAD51D paralog is unique in that it participates in both HR repair and telomere maintenance. RAD51D is also known to directly interact with the RAD51C and XRCC2 proteins. Rad51d splice variants have been reported in mouse and human tissues, supportive of a role for alternative splicing in HR regulation. The present study evaluated the interaction of the Rad51d splice isoform products with RAD51C and XRCC2 and their expression patterns. 相似文献43.
Pratap S. Jadon Virendra Gajbhiye Rajesh S. Jadon Kavita R. Gajbhiye Narayanan Ganesh 《AAPS PharmSciTech》2009,10(4):1186-1192
The aim of the present report was to develop nonionic surfactant vesicles (niosomes) to improve poor and variable oral bioavailability
of griseofulvin. Niosomes were prepared by using different nonionic surfactants span 20, span 40, and span 60. The lipid mixture
consisted of surfactant, cholesterol, and dicetyl phosphate in the molar ratio of 125:25:1.5, 100:50:1.5, and 75:75:1.5, respectively.
The niosomal formulations were prepared by thin film method and ether injection method. The influence of different formulation
variables such as surfactant type, surfactant concentration, and cholesterol concentration was optimized for size distribution
and entrapment efficiency for both methods. Result indicated that the niosomes prepared by thin film method with span 60 provided
higher entrapment efficiency. The niosomal formulation exhibited significantly retarded in vitro release as compared with free drug. The in vivo study revealed that the niosomal dispersion significantly improved the oral bioavailability of griseofulvin in albino rats
after a single oral dose. The maximum concentration (C
max) achieved in case of niosomal formulation was approximately double (2.98 μg/ml) as compared to free drug (1.54 μg/ml). Plasma
drug profile also suggested that the developed niosomal system also has the potential of maintaining therapeutic level of
griseofulvin for a longer period of time as compared to free griseofulvin. The niosomal formulation showed significant increase
in area under the curve0-24 (AUC; 41.56 μg/ml h) as compared to free griseofulvin (22.36 μg/ml h) reflecting sustained release characteristics. In conclusion,
the niosomal formulation could be one of the promising delivery system for griseofulvin with improved oral bioavailability
and prolonged drug release profiles. 相似文献
44.
Microbial plant interaction plays a major role in the sustainability of plants. The understanding of phytomicrobiome interactions enables the gene-editing tools for the construction of the microbial consortia. In this interaction, microbes share several common secondary metabolites and terpenoid metabolic pathways with their host plants that ensure a direct connection between the microbiome and associated plant metabolome. In this way, the CRISPR-mediated gene-editing tool provides an attractive approach to accomplish the creation of microbial consortia. On the other hand, the genetic manipulation of the host plant with the help of CRISPR-Cas9 can facilitate the characterization and identification of the genetic determinants. It leads to the enhancement of microbial capacity for more trait improvement. Many plant characteristics like phytovolatilization, phytoextraction, phytodesalination and phytodegradation are targeted by these approaches. Alternatively, chemical communications by PGPB are accomplished by the exchange of different signal molecules. For example, quorum-sensing is the way of the cell to cell communication in bacteria that lead to the detection of metabolites produced by pathogens during adverse conditions and also helpful in devising some tactics towards understanding plant immunity. Along with quorum-sensing, different volatile organic compounds and N-acyl homoserine lactones play a significant role in cell to cell communication by microbe to plant and among the plants respectively. Therefore, it is necessary to get details of all the significant approaches that are useful in exploring cell to cell communications. In this review, we have described gene-editing tools and the cell to cell communication process by quorum-sensing based signaling. These signaling processes via CRISPR- Cas9 mediated gene editing can improve the microbe-plant community in adverse climatic conditions. 相似文献
45.
Chowdhury Labrechai Mog Maurya Rajesh Kumar Singh Rajeev Kumar Mishra Shubhi Chauhan Nishita Jena J. K. Mohindra Vindhya 《Molecular biology reports》2021,48(11):7333-7342
46.
Das Aparimita Ganesan Harsha Sriramulu Sushmitha Marotta Francesco Kanna N. R. Rajesh Banerjee Antara He Fang Duttaroy Asim K. Pathak Surajit 《Molecular and cellular biochemistry》2021,476(11):4117-4131
Molecular and Cellular Biochemistry - Oxidative stress has been known to be the underlying cause in many instances of cancer development. The new aspect of cancer genesis that has caught the... 相似文献
47.
Allal Ouhtit Rajiv L. Gaur Zakaria Y. Abd Elmageed Augusta Fernando Rajesh Thouta Alison K. Trappey Mohamed E. Abdraboh Hassan I. El-Sayyad Prakash Rao Madhwa G.H. Raj 《生物化学与生物物理学报:癌评论》2009
CD146, also known as melanoma cell adhesion molecule or MCAM, is a key cell adhesion protein in vascular endothelial cell activity and angiogenesis. CD146 promotes tumor progression of many cancers including melanoma and prostate. Strikingly, its expression is frequently lost in breast carcinoma cells, and it may act as a suppressor of breast cancer progression. While upstream mechanisms regulating CD146 are well documented, our understanding of the downstream molecular events underlying its mode of action remains to be elucidated. This review aims to focus on the progress in understanding the signaling mechanisms and the functional relevance of CD146, a multifaceted molecule, in cancer with particular emphasis on its role in inhibiting breast cancer progression. 相似文献
48.
Nitin Kumar Rajesh K. Rohilla N. Roy Diwan S. Rawat 《Bioorganic & medicinal chemistry letters》2009,19(5):1396-1398
Synthesis and antibacterial activity of metronidazole–triazole conjugates are reported. Total 21 hybrid compounds have been synthesized with different substitution pattern on the triazole ring in order to study their influence on the antibacterial activity. These compounds demonstrated potent to weak antibacterial activity against Gram-positive, and Gram-negative bacteria. Six compounds have shown equal or better antibacterial activity against Gram-negative strains than the reference compound. 相似文献
49.
Nilkanth G. Aher Vandana S. Pore Nripendra N. Mishra Praveen K. Shukla Rajesh G. Gonnade 《Bioorganic & medicinal chemistry letters》2009,19(18):5411-5414
New bile acid-based amino sterols were synthesized in good yields from C-3β-oxiranes as key intermediates. These derivatives were evaluated for their in vitro antimicrobial properties against human pathogens. These compounds showed better antibacterial activity as compared to antifungal activity. Compounds 21 and 22 showed comparable antibacterial activity to gentamicin against Staphylococcus aureus with IC50 values of 5.14 and 4.46 μg/mL. This is the first report for the synthesis of C-3β-oxiranes on the steroids having A/B cis ring junction and these oxiranes have been used for the synthesis of amino sterols 17, 18, 21, and 22. 相似文献
50.