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11.
Instrumental neutron activation analysis (INAA) and atomic absorption spectrophotometry (AAS) were used to verify the protocols
for the quantification of zinc and magnesium in human whole blood. A study was conducted on group of volunteers consisting
of 131 patients having cardiovascular diseases (CVD) and 23 malignant hypertension (MH) patients along with 432 control subjects
with 218 male and 214 females. The elemental data of these elements has been exploited to establish the base line values in
control subjects. The possibility of any relationship between blood Mg and Zn levels with CVD and MH has also been investigated.
The mean blood Mg and Zn levels were found to be depleted in both CVD and MH patients as compared to normal subjects. In our
findings Mg and Zn were found to have an inverse relation with systolic and diastolic pressure. The reliability of the methods
was checked by the concurrent analysis of the IAEA reference material (RM) employing the optimized INAA and AAS protocols.
The determined values by both techniques were found to be in good agreement with the IAEA reference values. The elemental
data in whole blood samples of normal volunteers has also been compared with Mg and Zn contents reported by other countries. 相似文献
12.
N. Siddique S. Waheed M. Daud A. Rahman S. Ahmad 《Journal of Radioanalytical and Nuclear Chemistry》2007,274(1):181-186
Detailed investigations have been carried out on the well-known method of spectrophotometric determination of boron particularly
in uranium compounds as boron-curcumin complex after extraction into 2-ethyl hexane 1,3-diol (EHD) to understand a number
of parameters, which have not been addressed earlier in the literature. These include (i) effect of different acid media on
analytical results of boron which are employed for dissolution of nuclear fuel samples, (ii) effect of diluents namely ethyl
alcohol and N,N-dimethyl formamide on sensitivity of method which are employed for final dilution, and (iii) studies on loss
of boron, if any, during conversion of uranium compounds to U3O8. Based on the present studies, the existing procedure has been suitably modified to improve the sensitivity in the measurements.
In addition, this paper also describes about interference studies with Al, Cr, Mg, Ca, Fe, Mn, Mo, F− and W and amount of EHD on modified method. Absolute detection limit was found to be 10 ng. The precision and accuracy of
the method, is 3% at level 100 ng·g−1 of boron. 相似文献
13.
N. Siddique M. Jawad S. Waheed 《Journal of Radioanalytical and Nuclear Chemistry》2013,295(1):179-190
Twenty-eight pairs of coarse and fine air particulate samples were collected in front of an automotive workshop located at Tasmasipabad on Chaklala Road in Rawalpindi using a Gent sampler and polycarbonate filters. These samples were collected during the period; 7th to 27th of April 2009. The gravimetric data (PM2.5 and PM10) were obtained for these samples and were found to exceed the Pakistani standards. Black carbon (BC) was also determined using reflectance measurements and it was found that BC contributed significantly more to the fine mass than to the coarse fraction; i.e. ~10 to ~3 %, respectively. This is not surprising as soot is emitted by combustion processes and is usually found in the fine particulate mass. Using instrumental neutron activation analysis technique all 28 pairs of filters were analyzed for >30 elements. Major elements, in the coarse mass fraction, include Al, K, Fe, Sr, Na, and Zn implying soil as the major source while BC was found to be a higher contributor of PM2.5. An episode of high PM2.5 was observed on the 18th of April 2009. Back trajectory analysis showed that the air mass originated from the Middle East where a dust storm was in progress over Iraq. 相似文献
14.
The IR and resonance Raman spectra of the nickel(II) complexes of dibenzo[b,i][1,4,8,11]tetraaza[14]annulene (TAA) and 5,7,12,14-tetramethyldibenzo[b,i][1,4,8,11]tetraaza[14]annulene (TMTAA) have been measured and compared with ab initio calculations of the vibrational wavenumbers at the B3-LYP level using the LanL2DZ basis set. An excellent fit is found between the experimental and calculated data, enabling precise vibrational assignments to be made. Surface-enhanced resonance Raman spectra were obtained following adsorption on Ag electrodes, with potentials in the range -0.1 to -1.1 V vs Ag/AgCl. There is evidence for contributions from both the electromagnetic and charge transfer (CT) surface enhancement mechanisms. The data indicate that variations in band intensities with electrode potential can be interpreted in terms of the CT mechanism. 相似文献
15.
Tanveer Hussain Bokhari Muhammad Bilal Butt Saira Hina Munawar Iqbal Muhammad Daud Muhammad Imran 《Journal of Radioanalytical and Nuclear Chemistry》2017,314(3):1487-1496
The field of therapeutic nuclear medicine is emerging rapidly as choice of treatment in oncology and other cellular malignancies. The growth of this branch of nuclear medicine is greatly facilitated by the introduction of a number of new radiopharmaceuticals and radionuclides. 90Y-radiopharmaceuticals have confirmed their worth in medical and clinical areas in a very short span of time. The 90Y is a radioisotope widely used for therapeutic purposes and considerable perfection has been made to understand the chemistry of 90Y-labeled radiopharmaceuticals. The development of these radiopharmaceuticals can be made favorable by using appropriate buffer, incubation period, optimal pH, specific activity and reaction temperature. In this review, we have discussed the preparation of range of 90Y transporting biological molecules such as antibodies radiolabeled peptides, antigens and microsphere with their clinical applications. 相似文献
16.
Mohammed A. Al-Nuri Nidal A. Za'tar Maher A. Abu-Eid Mohammad A. Hannoun Waheed J. Al-Jondi Ahmad I. Hussein 《光谱学快报》2013,46(8):1539-1543
A new method for isolation and specrophotometric determination of emodin is presented. Emodin was isolated by thin layer chromatography (tlc) and column chromatography (cc) techniques, as an orange long crystalline substance. Emodin exhibits two absorption maxima, at 420 and 520 nm. Stability of the color and the effect of pH were studied. Beer's law is obeyed in the range 2–30 ppm. The method is applied to the determination of emodin in roots, stems, and leaves of Rumex cyprius plant. 相似文献
17.
The IAEA conducted the IAEA-CU-2006-06 Proficiency Test (PT) on “The determination of major, minor and trace elements in ancient
Chinese ceramic” in 2006. The results of this PT showed that of the 21 analytes reported by our laboratory 9 failed the precision
criteria. Therefore the results reported by our laboratory along with the results of other laboratories which carried out
analysis using neutron activation analysis (NAA) were studied. It was found that the major factor contributing towards data
falling in the “Warning” category, failing the precision criteria was the high uncertainties cited in the certificates of
the reference materials (RMs) used for quantification of data. In this regard, it is recommended that synthetic standards
should be prepared and used on a routine basis especially for the measurement of the elements K, Eu, Lu, Ta, Tb and Yb. 相似文献
18.
Waheed A Jones RA McCarty J Yang X 《Dalton transactions (Cambridge, England : 2003)》2004,(22):3840-3841
Reaction of Zn(OAc)(2).2H(2)O with pyrazine in refluxing ethanol gives the unusual heptanuclear complex Zn7(mu4-O)(2)(OAc)(10)(Pz)(2) (1) (OAc = acetate, Pz = pyrazine) in 46% yield. A single-crystal X-ray diffraction study of revealed a central Zn(7) core in which two pseudo-tetrahedral Zn(4) units are joined at a common vertex. The two pyrazine molecules are bound as terminal (eta1) ligands. 相似文献
19.
Saira Shahzadi Moazzam H. Bhatti Khadija Shahid Saqib Ali Saadia R. Tariq Mohammad Mazhar Khalid M. Khan 《Monatshefte für Chemie / Chemical Monthly》2002,133(8):1089-1096
Summary. Tributyltin(IV) derivatives of six different pharmaceutically active carboxylates were synthesized. The complexes were characterized
by different analytical techniques (elemental analysis; infrared, NMR, and mass spectroscopy). 119Sn NMR data were also recorded in six different coordinating and non-coordinating solvents. The antibacterial activities of
the compounds were tested using ten different bacteria relative to the reference drugs ampicillin and cephalexin.
Received September 20, 2001. Accepted (revised) December 6, 2001 相似文献
20.
Saira Hussain Ata ur Rehman David J. Luckett Syed Muhammad Saqlan Naqvi Christopher L. Blanchard 《Molecules (Basel, Switzerland)》2021,26(7)
Valorization of vegetable oil waste residues is gaining importance due to their high protein and polyphenol contents. Protease inhibitors (PIs), proteins from these abundantly available waste residues, have recently gained importance in treating chronic diseases. This research aimed to use canola meal of genetically diverse Brassica napus genotypes, BLN-3347 and Rivette, to identify PIs with diverse functionalities in therapeutic and pharmacological applications. The canola meal PI purification steps involved: native PAGE and trypsin inhibition activity, followed by ammonium sulfate fractionation, anion exchange, gel filtration, and reverse-phase chromatography. The purified PI preparations were characterized using SDS-PAGE, isoelectric focusing (IEF), and N terminal sequencing. SDS-PAGE analysis of PI preparations under native reducing and nonreducing conditions revealed three polymorphic PIs in each genotype. The corresponding IEF of the genotype BLN-3347, exhibited three acidic isoforms with isoelectric points (pI) of 4.6, 4.0, and 3.9, while Rivette possessed three isoforms, exhibiting two basic forms of pI 8.65 and 9.9, and one acidic of pI 6.55. Purified PI preparations from both the genotypes displayed dipeptidyl peptidase-IV (DPP-IV) and angiotensin-converting enzyme (ACE) inhibition activities; the BLN-3347 PI preparation exhibited a strong inhibitory effect with lower IC50 values (DPP-IV 37.42 µg/mL; ACE 129 µg/mL) than that from Rivette (DPP-IV 67.97 µg/mL; ACE 376.2 µg/mL). In addition to potential human therapy, these highly polymorphic PIs, which can inhibit damaging serine proteases secreted by canola plant pathogens, have the potential to be used by canola plant breeders to seek qualitative trait locus (QTLs) linked to genes conferring resistance to canola diseases. 相似文献