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341.
Nassim Vahidfar Amir R. Jalilian Yousef Fazaeli Ali Bahrami-Samani Davood Beiki Ali Khalaj 《Journal of Radioanalytical and Nuclear Chemistry》2013,295(2):979-986
Porphyrins are interesting derivatives with low toxicity, tumor avidity and rapid wash-out suggested as potential radiopharmaceuticals in radiolabeled form. In this work, [166Ho] labeled 5,10,15,20-tetrakis(phenyl) porphyrin ([166Ho]-TPP) was prepared using [166Ho]HoCl3 and 5,10,15,20-tetrakis(phenyl)porphyrin (H2TPP) for 12 h at 50 °C (radiochemical purity: >95 ± 2 % ITLC, >99 ± 0.5 % HPLC, specific activity: 0.9–1.1 GBq/mmol). Stability of the complex was checked in final formulation and human serum for 48 h. The partition coefficient was calculated for the compound (log P = 2.01). The biodistribution of the labeled compound in vital organs of wild-type rats was studied using scarification studies and SPECT. A detailed comparative pharmacokinetic study performed for 166Ho cation and [166Ho]-TPP performed up to 24 h. The complex is mostly washed out from the circulation through kidneys and in less extends from the liver. The kidney:blood, kidney:liver and kidney:muscle ratios 4 h post injection were 14, 3.6 and 7.38 respectively. 相似文献
342.
Taghrid S. Hafez Hisham Abdallah A. Yosef Hala M. Abou Yousef Eman F. Al-Amrousi Mohamed Refat H. Mahran 《Phosphorus, sulfur, and silicon and the related elements》2013,188(11):2277-2285
Dialkyl phosphites attack 6-(Aryliminomethyl)furobenzopyran-5-ones at the imine-carbon atom to give new phosphonate 1:1 adducts. The obtained compounds regenerate the starting materials upon thermolysis under reduced pressure. Structures of the new products were attested by compatible analytical and spectroscopic measurements. Insecticidal activity tests assured that some new compounds show marked potency against adults of Aphis gossypii (Glover), which infests cotton crops. Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file. 相似文献
343.
This work develops near-optimal controls for systems given by differential equations with wideband noise and random switching. The random switching is modeled by a continuous-time, time-inhomogeneous Markov chain. Under broad conditions, it is shown that there is an associated limit problem, which is a switching jump diffusion. Using near-optimal controls of the limit system, we then build controls for the original systems. It is shown that such constructed controls are nearly optimal. 相似文献
344.
Unsubstituted cyclic imides were synthesized from a series of cyclic anhydrides, hydroxylamine hydrochloride (NH2OH.HCl), and 4-N,N-dimethylamino-pyridine (DMAP, base catalyst) under microwave irradiation in monomode and multimode microwaves. This novel microwave synthesis produced high yields of the unsubstituted cyclic imides for both the monomode (61 - 81%) and multimode (84 - 97%) microwaves. 相似文献
345.
P2O5–PbO–BaO glass system has been investigated to see its potential use as radiation shielding material by studying the effect of the content of each of its composing oxides. The results show that this glass system is suitable as radiation shielding material and has some advantages comparing to the existing commonly used radiation protection glasses. 相似文献
346.
H. H. Hussain R. O. Hussain R. M. Yousef Q. Shamkhi 《Journal of Radioanalytical and Nuclear Chemistry》2010,284(1):43-47
People are exposed to ionizing radiation from the radionuclides that are present in different types of a natural sources,
of which building materials is one of the most important sources. Radionuclides in building materials belonging to 238U, 232Th series as well as radioisotope of Potassium 40K are the major contributors of outdoor terrestrial natural radiation. This study is the first ever in Iraq. In order to estimate
the radiological impact to the dweller, the activity concentration of radionuclides present in various Iraqi building materials
were analyzed using Gamma-spectrometry. The radiation hazard indexes were calculated based on the above results. The results
showed that the activity concentration of 238U, 232Th and 40K was between 32.9 Bq/kg (Najaf gypsum)–179.32 Bq/kg (Karbala cement), 1.98 Bq/kg (Najaf sand)–17.43 Bq/kg (Qadisiya brick)
and 108.73 Bq/kg (Karbala sand)–977.79 Bq/kg (Najaf brick), respectively. All values of Radium equivalent activities were
found to be less than the maximum permissible limit and the internal hazard indexes (except Karbala cement) were less than
unity for the radiation hazard. Some samples have external annual dose and external hazard index values greater than unity. 相似文献
347.
The aim of this work is to investigate the possibility of using industrial wastes as new grinding aids in cement industry. Two samples of Soapstock from different oils were used (Sunflower Oil (SO), Corn Oil (CO)). For this purpose, one reference sample was produced without using any admixture and another one using reference grinding aids (Triethanolamine TEA).The raw mixes were characterized via differential scanning calorimetry (DSC), FT-IR technique, chemical analysis by X-ray florecence (XRF), X-ray powder diffraction (XRD), and mineral composition by Bouge equation and determination of free calcium oxide (CaOf) for clinker. Grindability was determined according to PSD and resides on sieve 90 μm.In all cases the addition of grinding aids resulted in the improvement of grindability (fact that was attributed to the additive ability not only to reduce resistance to combination, but also to prevent agglomeration and powder coatings of ball and mill), and the clinker produced by this admixture was not effective. 相似文献
348.
Biodegradable polymer-based magnetic gels have been synthesized using hydroxypropyl cellulose and maghemite. These magnetic gels have a network of nanoparticles of hydroxypropyl cellulose (30–100 nm) and a homogeneous distribution of nanosized maghemite (~7 nm). This has been observed in a STEM micrograph. The surface structure of the gels has been observed by atomic force microscopy, while transmission electron microscopy has shown the distribution of iron oxide in HPC gel nanoparticles. These gels have magneto-elastic properties. The magnetic susceptibility and magnetization of these gels are measured by a superconducting quantum interference device magnetometer. 相似文献
349.
The reaction of (1R,2R)‐(–)‐1,2‐diaminocyclohexane ( 1 ) [DACH] with the aldehyde (1R)‐(–)‐myrtenal ( 2 ) in MeOH afforded the bidentate diimine ligand, (1R,2R)‐(–)‐N1,N2‐bis{(1R)‐(–)myrtenylidene}‐1,2‐diaminocyclohexane ( 3 ) in a high yield. Reduction of 3 using LiAlH4 led to the formation of the desired ligand ( 4 ) (1R,2R)‐(–)‐N1,N2‐bis{(1R)‐(–)myrtenyl}‐1,2‐diaminocyclohexane. Treatment of compound 4 with K2PtCl4 or K2PdCl4 yielded the corresponding platinum(II) and palladium(II) complexes, Pt‐5 and Pd‐6 , respectively. The reaction of compound 3 with K2PtCl4 gave the diimine complex Pt‐7 . The cytotoxic activity of the complexes Pt‐5 , Pd‐6 and Pt‐7 was tested and compared to the approved drugs, cisplatin ( Cis ‐Pt ) and oxaliplatin ( Ox‐Pt ). The complexes ( Pt‐5 , Pd‐6 and Pt‐7 ) inhibit L1210 cell line proliferation with an IC50 of 0.6, 4.2, and 0.7 μL, respectively as evidenced by measuring thymidine incorporation. 相似文献
350.
Yousef Fazaeli Amir R. Jalilian Mostafa M. Amini Ali Rahiminejad-kisomi Saeed Rajabifar Fatemeh Bolourinovin Sedigheh Moradkhani 《Journal of Radioanalytical and Nuclear Chemistry》2011,288(1):17-24
[67Ga]labeled tetraphenyl porphyrin ([67Ga]-TPP) was prepared using freshly prepared [67Ga]GaCl3 and tetraphenyl porphyrin (TPPH2) for 30–60 min at 25 °C (radiochemical purity: >97 ± 1% ITLC, >98 ± 0.5% HPLC, specific activity: 13–14 GBq/mmol). Stability
of the complex was checked in final formulation and human serum for 24 h. The partition coefficient was calculated for the
compound (log P 1.89). The biodistribution of the labeled compound in vital organs of wild-type rats was studied using scarification studies
and SPECT imaging up to 24 h. A detailed comparative pharmacokinetic study performed for 67Ga cation and [67Ga]-TPP. The complex is mostly washed out from the circulation through kidneys and can be an interesting tumor imaging/targeting
agent due to low liver uptake and rapid excretion through the urinary tract. 相似文献