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211.
212.
S. Firdous M. Nawaz M. Ahmed S. Anwar A. Rehman R. Rashid A. Mahmood 《Laser Physics》2012,22(6):1090-1094
This study demonstrates the use of Raman spectroscopy for the direct measurement of diabetic sugar in human blood using 532 nm laser system. Raman spectra were collected from whole blood drawn from 21 individuals. We have elicited a reliable glucose signature in diabetic patients, and measured glucose levels in blood serum of normal, healthy diabetic and diabetic patients with other malignancies like cancer and hepatitis. Quantitative predictions of glucose spectra illustrate the predictions based on molecular information carried by the Raman light in highly light-scattering and absorbing media. Raman spectrum peaks for diabetic blood serum are observed at 1168, 1531, 1463, 1021 cm?1 with intensity level 17000 to 18500 pixels attributed to carbohydrates, proteins, lipids, collagen, and skeletal C-C stretch of lipids acyl chains. Raman spectra for normal, diabetic patients having cancer and hepatitis were also recorded. This in vitro glucose monitoring methodology will lead in vivo noninvasive on-line monitoring having painless and at the same time the data will be displayed on-line and in real time. The measured Raman peaks provides detailed bio-chemical fingerprint of the sample and could confer diagnostic benefit in a clinical setting. 相似文献
213.
In this work Raman spectra of normal and dengue infected serum and whole blood were analyzed. In normal whole blood and serum characteristic peaks were observed when excited at 442 and 532 nm. In dengue whole blood and serum all peaks found to be blue shifted with reduced Raman intensity. Dengue whole blood and serum shows two peaks at 1614 and 1750 cm?1 which are due to presence of Immunoglobulin antibodies IgG and IgM. Whole study provides a route of information for diagnosis of dengue viral infection. 相似文献
214.
Najeeb Ur Rehman Abdul Latif Khan Zahid Hassan Tania Shamim Rizvi Ahmed Al‐Harrasi Zabta Khan Shinwari Javid Hussain 《Helvetica chimica acta》2015,98(9):1240-1244
One new cyclopropyl‐triterpenoid ( 1 ), along with four known constituents including octacosan‐1‐ol ( 2 ), pentacosanoic acid ( 3 ), β‐sitosterol ( 4 ), and β‐sitosterol 3‐O‐β‐D ‐glucopyranoside ( 5 ) were isolated from the aerial parts of Ochradenus arabicus for the first time. These compounds were isolated by repeated column chromatography followed by further purification through recycling HPLC. The structure of the new secondary metabolite 1 was established on the basis of UV, IR, 1D‐ (1H‐ and 13C‐) and 2D‐NMR (HMBC and HSQC), and MS spectral data. The molecular mass was determined by HR‐MS, and hence the molecular formula was deduced. The configurations of stereogenic centers in the molecule were assigned by NOESY experiments, along with biogenetic considerations. The structures of the known compounds were confirmed by comparison of their physical and spectroscopic data with those reported in literature. 相似文献
215.
Musa Kaleem Baloch Gulzar Hameed Shahid Iqbal Arjamand Bano Wajid Rehman 《Journal of Dispersion Science and Technology》2013,34(4):498-506
Emulsions stand among the most important multiphase fluids, exhibiting various complicated phenomenon. To understand the process of emulsification, the Taylor equation has been extended to incorporate the parameters that depend on molecular mass of oil and their contents and the amount of surfactant added. To test the validity of the proposed equations, four well-defined short chain (n-hexane, n-heptane, n-decane, and kerosene) oils were emulsified in water and the results were compared with the experimental ones. It has been concluded that the extended Taylor equation worked well, even in the presence of surfactant. The quality of the emulsion defined and discussed in terms of size and number of droplets was best near CMC of the surfactant used. A relationship has also been derived between CMC of surfactant and its distribution coefficient, which allows the exact value of one parameter to be determined if other is known. 相似文献
216.
Faheema Khan Khalid Rehman Hakeem Tariq O. Siddiqi Altaf Ahmad 《Applied biochemistry and biotechnology》2013,170(2):257-272
In order to investigate the influence of genetic background on salt tolerance in soybean (Glycine max), ten soybean genotypes (Pusa-20, Pusa-40, Pusa-37, Pusa-16, Pusa-24, Pusa-22, BRAGG, PK-416, PK-1042, and DS-9712) released in India, were selected and grown hydroponically. The 10-day-old seedlings were subjected to 0, 25, 50, 75, 100, 125, and 150 mM NaCl for 15 days. Plant growth, leaf osmotic adjustment, and random amplified polymorphic DNA (RAPD) analysis were studied. In comparison to control plants, the plant growth in all genotypes was decreased by salt stress, respectively. Salt stress decreased leaf osmotic potential in all genotypes; however, the maximum reduction was observed in genotype Pusa-24 followed by PK-416 and Pusa-20, while minimum reduction was shown by genotype Pusa-37, followed by BRAGG and PK-1042. Pusa-16, Pusa-22, Pusa-40, and DS-9712 were able to tolerate NaCl treatment up to the level of 75 Mm. The difference in osmotic adjustment between all the genotypes was correlated with the concentrations of ion examined such as Na+ and the leaf proline concentration. These results suggest that the genotypic variation for salt tolerance can be partially accounted by plant physiological measures. Twenty RAPD primers revealed high polymorphism and genetic variation among ten soybean genotypes studied. The closer varieties in the cluster behaved similarly in their response to salinity tolerance. Intra-clustering within the two clusters precisely grouped the ten genotypes in sub-cluster as expected from their physiological findings. Our study shows that RAPD technique is a sensitive, precise, and efficient tool for genomic analysis in soybean genotypes. 相似文献
217.
218.
Saeed Ur-Rehman Muhammad Ikram Sadia Rehman Shah Nawaz 《Frontiers of Chemistry in China》2011,6(2):98-104
Coordination compounds of modified diamine, the basic unit of which are ethylenediamine, with that of Co (II) are prepared.
The modified diamines are ethylenediaceticacid (EDDA) and N,N,N,N-tetaraethylene-1,2-diamine (TEEDA). These diamines are characterized
through 1H-NMR, 13C-NMR, elemental analysis and IR techniques. Cobalt (II) complexes of these two ligands were prepared and characterized by
physical measurements including elemental analysis, IR, UV-Visible, magnetic susceptibilities and conductance measurements.
Antibacterial activities are also carried out in order to investigate the biological activity upon complexation. They were
screened against four pathogenic bacteria like Escherichia coli, Pseudomonas aeroginosa, Klesbella pneumonia and Staphylococcus aureus. The results showed significant enhancement in activities. 相似文献
219.
H. Ur Rehman S. Ahmad H. Ajaz M. Hanif M. Altaf H. Stoeckli-Evans 《Journal of Structural Chemistry》2011,52(1):160-165
A polymeric silver(I) complex, bis(N-methylthiourea)silver(I) nitrate, {[Ag(Metu)2]NO3}
n
is prepared and its crystal structure is determined. The compound crystallizes in the monoclinic C2/c space group. In the structure, distorted AgS4 tetrahedra are linked through the sulfur atoms of the Metu ligand to form isolated infinite chains of the type [Ag(SR)2]
n
n+. The cationic chains are separated from each other by nitrate ions that do not coordinate to the metal ion. The chains are
bridged via N-H...O hydrogen bonds involving the nitrate ions. The complex exhibits an Ag—Ag separation of ∼3.21 ? indicating
the existence of significant argentophilic interactions. An upfield shift in the >C=S resonance of Metu in 13C NMR and downfield shift in the N-H resonance in 1H NMR are consistent with sulfur coordination to silver(I). 相似文献
220.
The fields of chemical and biosensors have grown tremendously from the improvements in the transducer and readout components, as well as in sensing materials and interface designs to meet the always rising standards for accuracy, cost, portability, and accessibility in a broad range of sensing applications. Although the transducer and readout components can often be interchangeable for a specific target analyte, the receptor element of the sensor device, which is the ‘sensing material with its interface chemistry,’ must be specifically tailored to any sensing mechanism. The interfacial properties of the sensing components play essential roles in determining the analytical performance and the overall cost of the sensor technology in both technical and commercial senses. Ionic liquids (IL) are liquids often composed of bulky organic cations or anions, whereas conductive polymers (CPs) are solids with dopant ions in a rigid organic framework. Both ILs and CPs have been demonstrated as promising smart/tunable and low-cost materials for chemical and biosensor development. In this article, we present our opinion discussing the unique features of using ILs and CPs as molecular building blocks to design robust and functional sensing interfaces for next-generation, low-cost, and miniaturized electrochemical sensor development. 相似文献