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111.
Sabjan Khaleel Basha Kasivelu Govindaraju Ramar Manikandan Jong Seog Ahn Eun Young Bae Ganesan Singaravelu 《Colloids and surfaces. B, Biointerfaces》2010,75(2):405-409
Current discovery demonstrates the rapid formation of gold nanoparticles with guavanoic acid a phytochemical of Psidium guajava (Pg). The pharmacological capabilities of the phytochemicals present in the leaves of Pg and their ability to generate gold nanoparticles is presented herein. The new genre of green nanoparticles exhibit remarkable Protein Tyrosine Phosphatase 1B (PTP 1B) inhibitory activity and in vitro stability in various physiological medium including saline, histidine, cysteine, bovine serum albumin (BSA), human serum albumin (HSA) and buffers (pH 5, 7 and 9). It is predicted that this new technology will be felt greatly in several routes of pharmaceuticals. 相似文献
112.
B. Krishna Kumar A. Krishnamoorthy S. Pavai Madheswari S. Sadiq Basha 《Queueing Systems》2007,56(3-4):133-141
A transient solution is obtained analytically using continued fractions for the system size in an M/M/1 queueing system with catastrophes, server failures and non-zero repair time. The steady state probability of the system
size is present. Some key performance measures, namely, throughput, loss probability and response time for the system under
consideration are investigated. Further, reliability and availability of the system are analysed. Finally, numerical illustrations
are used to discuss the system performance measures.
相似文献
113.
Ameer Fawad Zahoor Muhammad Yousaf Rabia Siddique Sajjad Ahmad Syed Ali Raza Naqvi Sayyad Muhammad Ali Rizvi 《合成通讯》2017,47(11):1021-1039
Enoxacin, levofloxacin, and gatifloxacin represent one of the most important prerogative scaffolds in drug development. They possess broad spectrum antimicrobial and anti-inflammatory activities. They inhibit bacterial growth by blocking their topoisomerase enzyme which is necessary for the proper functioning of bacterial DNA. In this article, we have reviewed the synthetic approaches involved in the synthesis of derivatives of enoxacin, levofloxacin, and gatifloxacin. 相似文献
114.
Abhishek Sud Pramod S. Chaudhari Ishu Agarwal Amjad Basha Mohammad Vilas H. Dahanukar Rakeshwar Bandichhor 《Tetrahedron letters》2017,58(19):1891-1894
A novel reaction involving in situ redox conversion of glyoxylate esters to glycine is described. Simple starting materials and mild conditions for the synthesis of glycine derivatives probably indicate a pathway towards prebiotic chemistry. This proceeds analogous to Cannizzaro reaction involving ammonia therefore it can be termed as intramolecular Aza-Cannizzaro type reaction. This reaction is examined in detail with an aid of computational analysis to corroborate the proposed mechanism. 相似文献
115.
Rukaiyya Sirajuddin Khan Mahibalan Senthi Poorna Chandra Rao Ameer Basha Mallika Alvala Dinesh Tummuri 《Natural product research》2015,29(11):1069-1073
The study was aimed to identify cytotoxic leads from Abutilon indicum leaves for treating glioblastoma. The petroleum ether extract, methanol extract (AIM), chloroform and ethyl acetate sub-fractions (AIM-C and AIM-E, respectively) prepared from AIM were tested for cytotoxicity on U87MG human glioblastoma cells using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. These extracts exhibited considerable activity (IC50 values of 42.6–64.5 μg/mL). The most active AIM-C fraction was repeatedly chromatographed to yield four known compounds, methyl trans-p-coumarate (1), methyl caffeate (2), syringic acid (3) and pinellic acid (4). Cell viability assay of 1–4 against U87MG cells indicated 2 as most active (IC50 value of 8.2 μg/mL), whereas the other three compounds were much less active. Interestingly, compounds 1–4 were non-toxic towards normal human cells (HEK-293). The content of 2 in AIM-C was estimated as 3% by HPLC. Hence, presence of some more active substances besides methyl caffeate (2) in AIM-C is anticipated. 相似文献
116.
117.
Proteomics Approach to Identify Unique Xylem Sap Proteins in Pierce’s Disease-Tolerant Vitis Species
Sheikh M. Basha Hifza Mazhar Hemanth K. N. Vasanthaiah 《Applied biochemistry and biotechnology》2010,160(3):932-944
Pierce’s disease (PD) is a destructive bacterial disease of grapes caused by Xylella fastidiosa which is xylem-confined. The tolerance level to this disease varies among Vitis species. Our research was aimed at identifying unique xylem sap proteins present in PD-tolerant Vitis species. The results showed wide variation in the xylem sap protein composition, where a set of polypeptides with pI between 4.5 and 4.7 and M r of 31 kDa were present in abundant amount in muscadine (Vitis rotundifolia, PD-tolerant), in reduced levels in Florida hybrid bunch (Vitis spp., PD-tolerant) and absent in bunch grapes (Vitis vinifera, PD-susceptible). Liquid chromatography/mass spectrometry/mass spectrometry analysis of these proteins revealed their similarity to β-1, 3-glucanase, peroxidase, and a subunit of oxygen-evolving enhancer protein 1, which are known to play role in defense and oxygen generation. In addition, the amount of free amino acids and soluble sugars was found to be significantly lower in xylem sap of muscadine genotypes compared to V. vinifera genotypes, indicating that the higher nutritional value of bunch grape sap may be more suitable for Xylella growth. These data suggest that the presence of these unique proteins in xylem sap is vital for PD tolerance in muscadine and Florida hybrid bunch grapes. 相似文献
118.
Ameer Jaber 《Journal of Algebra》2010,323(7):1849-1859
By a theorem of Albert's, a central simple associative algebra has an involution of the first kind if and only if it is of order 2 in the Brauer group. Our main purpose is to develop the theory of existence of anti-automorphisms of order 2 of the first kind on finite dimensional central simple associative superalgebras over K, where K is a field of arbitrary characteristic. First we need to generalize the Skolem–Noether Theorem to the superalgebra case. Then we show which kind of finite dimensional central simple superalgebras have an anti-automorphism of order 2 of the first kind. 相似文献
119.
The 2-(5,6-dihydroxy-1,2,3,4-tetrahydro-1-naphthyl)imidazoline 1 is a recently reported potent alpha-adrenergic agent [1]. In continuation of our work on the synthesis of potential adrenergic agents we required imidazoisoindole 2 in order to investigate the biological effects of incorporation of additional rigidity into the parent system. This paper describes the synthesis of 2 via an intramolecular Diels-Alder reaction and a novel Lawesson's reagent mediated cyclization. 相似文献
120.
Radon has been recognized to be one of the major contributors to the natural radiation causing even lung cancer if it is present at enhanced levels. Its monitoring at highly confined locations such as underground caves, mines and tube-wells is very essential for finding the health related hazards among the workers. This paper reports the investigations of the levels of radon, thoron and their progeny monitored in the tube-wells of the Halls of residence at A.M.U., Aligarh, which lies in the subtropical region of Indo-Gangetic plains situated in North India. The twin cup dosimeters were fixed for exposure at a depth of 5?C35?feet with a difference of 5?feet from the ground surface. The values of radon and thoron concentrations were found to vary from 6.58 to 1218.57 and 7.41?C3226.61?Bq?m?3, respectively. The preliminary results of this study for ??bare mode?? detectors have been separately published and compared with the recent data. 相似文献