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101.
Nand K. Singh Nagendra Singh Ajit Sodhi Anju Shrivastava Guru C. Prasad 《Transition Metal Chemistry》1996,21(6):556-559
Summary The new potential tetradentate ligand N-salicyl-N-thiobenzohydrazide (H2SBTH) and its Cu complex, [Cu(SBTH)], have been prepared and characterized by physico-chemical studies. In vivo antitumour activity of [Cu(SBTH)] has been tested against breast tumour in C3H/J strain mice; LD
50 values were also calculated. The cytotoxicity and antitumour effect of [Cu(SBTH)] is a maximum at 100 mg kg-1 body weight injected intraperitoneally in mice carrying breast tumour. In vitro results of the ligand and the complex on P-815 (murine mastocytoma) and K-562 (human erythroleukemia cells) indicate that these compounds show significant inhibition on 3H-thymidine and 3H-uridine incorporation in DNA and RNA in these tumour cells. Light microscopic study of the treated tumour mass demonstrated that certain cellular degradation, such as disappearance of mitotic figures, loss in cellular compactness, distortion of nucleus and disruption of cytoplasmic boundaries, take place in complex-treated mice with tumours. 相似文献
102.
Devarayapalli KC Pack SP Kamisetty NK Nonogawa M Watanabe S Kodaki T Makino K 《Analytical and bioanalytical chemistry》2007,388(4):919-928
DNA chips prepared on a flat glass surface have unavoidable drawbacks when used for quantitative analysis. In an attempt to
overcome this problem, we constructed an HPLC-type system suitable for quantitative analysis that enables base sequence- and
T
m-dependent DNA oligomer separation in a flow system. A small open tubular capillary column (300-mm × 100-μm I.D.) was used.
The DNA oligomers used as probes had an amino group at the 5′-end and were immobilized on the inner silica surface of the
capillary column which had been sequentially treated with 3-aminopropyltriethoxysilane, butyltrimethoxysilane, and disuccinimidylglutarate.
Using the combination of probe-immobilized column placed in a column oven equipped with temperature gradient function, a nano-flow-controllable
pump, a small sample-loading injector, and a capillary-fitted UV detector, we succeeded in separating complementary and non-complementary
DNA oligomers in specific and quantitative modes. We also designed a temperature gradient strategy for efficient separation
of target DNA oligomers in DNA mixture samples. Using a column carrying two different probes with similar T
m values, their complementary target DNA oligomers were also separated and detected. The developed DNA open tubular capillary
column system investigated in the present study could be further improved as an alternative tool to DNA chips to be used for
the quantitative analysis of DNA or mRNA samples.
Kamakshaiah Charyulu Devarayapalli and Seung Pil Pack contributed equally to this paper. 相似文献
103.
Jhillu S. Yadav Basi V. Subba Reddy Nagendra Nath Yadav Ashutosh Pratap Singh Madavi Choudhary Ajit C. Kunwar 《Tetrahedron letters》2008,49(42):6090-6094
Baylis-Hillman acetates undergo smooth alkynylation with aryl-susbstituted iodoalkynes in the presence of indium metal in refluxing dichloromethane to furnish 1,4-enynes in high yields with (E)-stereoselectivity. In the absence of Lewis acid, the reaction follows both SN2 and SN2′ pathways affording 1:1 mixtures of 1,4-enynes. Upon addition of 10 mol % of InBr3, the reaction proceeds preferably in the SN2′ manner. In the case of adducts derived from acrylonitrile, the corresponding products are obtained in fairly good yields and with (Z)-stereoselectivity. 相似文献
104.
Steel industries are a major contributor to aerosols in steel cities like Rourkela.We designed an air quality sampling program to characterize total suspended particulate(TSP) aerosol in urban areas of Rourkela and to identify their steel-related and other sources.Monitoring was carried out over 8 h,twice per week from January 2011 to December 2012.Metallic species of TSP aerosols were analyzed using an atomic absorption spectrophotometer;ionic species using the IS 3025 method;and carbonaceous species using a total organic carbon analyzer.Enrichment factor and Spearman’s rank correlation analysis were carried out on compositional data.Significant seasonal variations were observed for TSP with totals in summer>spring>winter>monsoon.Low concentrations during monsoon reflected wet scavenging,while high concentrations during summer were related to wind turbulence and low humidity.The chemical mass balance model CMB8.2 was applied to apportion sources.Particles related to steel production,road dust,and soil were dominant in all seasons.A fertilizer plant was found to contribute particles in summer and monsoon.Wood combustion,diesel exhaust,and liquefied petroleum gas contributed significantly in spring and winter.While diesel exhaust,industrial manufacturing,solid waste burning,cement kilns,and construction were found to contribute to TSP at various times throughout the year. 相似文献
105.
In many tracking control problems, pre-specified bounds for the evolution of the tracking error should be met. The ‘funnel controller’ addresses this requirement and guarantees transient performance for a fairly large class of systems. In addition, only structural assumptions on the underlying system are made; the exact knowledge of the system parameters is not required. This is in contrast to most classical controllers where only asymptotic behaviour can be guaranteed and the system parameters must be known or estimated. Until now, the funnel controller was only studied theoretically. We will present the results of an analogue implementation of the funnel controller. The results show that the funnel controller works well in reality, i.e. it guarantees the pre-specified error bounds. The implementation is an analogue circuit composed of standard devices and is therefore suitable for a broad range of applications. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
106.
Tirtha Raj Acharya Pradeep Lamichhane Rizwan Wahab Dinesh Kumar Chaudhary Bhanu Shrestha Leela Pradhan Joshi Nagendra Kumar Kaushik Eun Ha Choi 《Molecules (Basel, Switzerland)》2021,26(24)
This paper compared the effects of A. indica plant proteins over chemical methods in the morphology of zinc oxide nanoparticles (ZnO NPs) prepared by a co-precipitation method, and ethanol sensing performance of prepared thin films deposited over a fluorene-doped tin oxide (FTO) bind glass substrate using spray pyrolysis technique. The average crystallite sizes and diameters of the grain-sized cluster ZnO NPs were 25 and (701.79 ± 176.21) nm for an undoped sample and 20 and (489.99 ± 112.96) nm for A. india dye-doped sample. The fourier transform infrared spectroscopy (FTIR) analysis confirmed the formation of the Zn–O bond at 450 cm−1, and also showed the presence of plant proteins due to A. indica dye extracts. ZnO NPs films exhibited good response (up to 51 and 72% for without and with A. indica dye-doped extracts, respectively) toward ethanol vapors with quick response-recovery characteristics at a temperature of 250 °C for undoped and 225 °C for A. indica dye-doped ZnO thin films. The interaction of A. indica dye extracts helps to decrease the operating temperature and increased the response and recovery rates of the sensor, which may be due to an increase in the specific surface area, resulting in adsorption of more oxygen and hence high response results. 相似文献
107.
Patel Swati Baghel Gyanendra Singh Chauhan Nagendra Singh Rathiya Satyawati Sahu Umakant Parihar Arun Singh Kumar Awanish Gupta Prashant Kumar 《平面色谱法杂志一现代薄层色谱法》2021,34(6):493-502
JPC – Journal of Planar Chromatography – Modern TLC - The present era is witnessed by the increasing demand for herbal medicine. Therefore, the preparation of herbal drugs is warranted... 相似文献
108.
A simple and efficient protocol is developed for the synthesis of 5-substituted 1H-tetrazole derivatives from various nitriles and sodium azide (NaN3) via [3+2] cycloaddition reaction using B(C6F5)3 as a catalyst. The present synthetic method displayed significant advantages such as low catalyst loading, mild reaction conditions, low toxicity, easy work-up, high yields, and compatibility with other functional groups. 相似文献
109.
110.
Yadav JS Reddy BV Yadav NN Gupta MK Sridhar B 《The Journal of organic chemistry》2008,73(17):6857-6859
Gold(III) chloride is found to be an effective catalyst for the addition of alkynes on activated quinoline/isoquinolines to produce a series of alkynyl-substituted 1,2-dihydroquinolines and isoquinolines in a single-step operation. The easy availability of starting materials, convenient synthetic procedure, operational simplicity, and high regioselectivity makes this strategy very useful for the preparation of enyne derivatives of aza-aromatic compounds. 相似文献