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121.
Hana Bashir Shawish Mohammadjavad Paydar Chung Yeng Looi Yi Li Wong Elaheh Movahed Siti Nadiah Abdul Halim Won Fen Wong Mohd-Rais Mustafa Mohd Jamil Maah 《Transition Metal Chemistry》2014,39(1):81-94
Nickel(II) complexes with 2,3-dihydroxybenzaldehyde N4-substituted thiosemicarbazone ligands (H3L1–H3L4) have been synthesized and characterized with the aim of evaluating the effect of N4 substitution in the thiosemicarbazone moiety on their coordination behavior and biological activities. Two series of nickel(II) complexes with the general formulae [Ni(H3L)(H2L)]ClO4 and [Ni2(HL)2] were characterized by analytical and spectral techniques. The molecular structure of one of the complexes, namely, [Ni(H3L4)(H2L4)]ClO4 was established by single crystal X-ray diffraction studies. The crystal structure of this complex revealed that two H3L4 ligands are coordinated to nickel(II) in different modes; one as a neutral tridentate ONS ligand and the other is as a monoanionic tridentate (ONS?) ligand. The antimicrobial activities of the compounds were tested against 25 bacterial strains via the disc diffusion method, and their minimum inhibitory concentration (MIC) and minimum microbicidal concentration were evaluated using microdilution methods. With a few exceptions, most of the compounds exhibited low-to-moderate inhibitory activities against the tested bacterial strains. However, the complexes [Ni2(HL3)2] (7) and [Ni2(HL4)2] (8) indicated higher inhibitory activity against Salmonella enterica ATCC 9068 (MIC values 15.7 and <15.7 μg/ml, respectively), compared with gentamicin as the positive control (MIC 25 μg/ml). Complex (7) also inhibited Streptococcus pneumoniae more efficiently (MIC 31.2 μg/ml), compared with gentamicin (MIC > 50 μg/ml). The toxicities of the compounds were tested on brine shrimp (Artemia salina), where no meaningful toxicity level was noted for both the free ligands and the complexes. The cytotoxicities of the compounds on cell viability were determined on MCF7, PC3, A375, and H413 cancer cells in terms of IC50; complexes [Ni(H3L3)(H2L3)]ClO4 (3), [Ni2(HL3)2] (7) and [Ni2(HL4)2] (8) exhibited significant cytotoxicity on the tested cell lines. 相似文献
122.
KTP crystals have been grown by two nucleation techniques namely spontaneous nucleation in flux medium and nucleation on Pt rod using K6P4O13 flux.10 °C/h, 7 °C/h, 0.8 °C/h, 0.4 °C/h and 0.2 °C/h cooling rates were applied for spontaneous nucleation and crystals up to 15 × 7 × 4 mm3 in size were grown. 1 °C/h and 0.8 °C/h cooling rates were also used for nucleation on Pt rod and crystals up to 8 × 6 × 3 mm3 in size were grown. The effect of cooling rate on size, morphology and optical quality of grown crystals by both techniques were studied. For nucleation on Pt rod upper and lower rotation rates limits and an optimum rotation rate were distinguished for each cooling rate. Quality of the grown crystals by both techniques was characterized by optical transmission analysis. 相似文献
123.
N2O4 was easily impregnated on polyethyleneglycol to give a stable reagent. Polyethyleneglycol‐N2O4 ( PEG‐N2O4 ) system was used as an effective oxidizing agent for the oxidation of urazoles and bis‐urazoles to their corresponding triazolinediones and also for the aromatization of 1,4‐dihydropyridines into the corresponding pyridine derivatives under mild conditions at room temperature with good to excellent yields. 相似文献
124.
Najmabadi H Ghamari A Sahebjam F Kariminejad R Hadavi V Khatibi T Samavat A Mehdipour E Modell B Kariminejad MH 《Community genetics》2006,9(2):93-97
For 14 years, Iranian scientists have worked to develop a national thalassemia prevention program. Although historically abortion was considered unacceptable in Iran, intensive consultations led to the clerical approval of induced abortion in cases with beta-thalassemia major in 1997, and a nationwide prevention program with screening, counseling and prenatal diagnosis (PND) networks has been developed. This paper reports the experience from one of the two national PND reference laboratories. As one of the oldest reference laboratories, we performed a total of 906 PND in 360 couples at risk for thalassemia from 1990 to 2003. Direct and indirect mutation detection methods were applied for all cases. In total, 22 mutations were tested routinely, and an additional 30 rare mutations were identified. 208 fetuses were found to be normal, 215 fetuses had beta-thalassemia major, and 435 fetuses were carriers of the trait. In 40 cases, we only defined one allele. In 8 cases, we were unable to provide any diagnosis, corresponding to 0.9%. Our data support the functionality of the Iranian beta-thalassemia prevention program. The success of this system in Iran, a multiethnic and Islamic-based country, would mean that it might be applied as an adaptive system for neighboring and other Islamic countries. 相似文献