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Journal of Thrombosis and Thrombolysis - Thrombotic thrombocytopenic purpura (TTP) which can cause significant mortality is a thrombotic microangiopathy due to deficiency of VWF cleaving protease...  相似文献   
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Two polymers based on (3E,7E)-3,7-bis(2-oxoindolin-3-ylidene)benzo[1,2-b:4,5-b′]difuran-2,6(3H,7H)-dione (BIBDF) coupled with (E)-2-(2-(thiophen-2-yl)vinyl)thiophene (TVT) or dithienylbenzothiadiazole (TBT), namely PBIBDF-TVT and PBIBDF-TBT were synthesized via the Stille coupling reaction. The effect of benzothiadiazole or vinylene-π spacer of the copolymers on optical properties, energy levels, electronic device performance and microstructure were studied. It was found that PBIBDF-TBT based OFET devices, annealed at 180 °C, showed better performance with the highest electron mobility of 2.9 × 10−2 cm2 V s−1 whereas PBIBDF-TVT polymer exhibited 5.0 × 10−4 cm2 V s−1. The two orders of magnitude higher electron mobility of PBIBDF-TBT over PBIBDT-TVT is a clear indicator of the better charge transport ability of this polymer semiconductor arising from its higher crystallinity and better donor–acceptor interaction.

Bottom-gate-top-contact OFET device structure using PBIBDF-TVT and PBIBDF-TBT based polymer semiconductors.  相似文献   
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A simple and efficient route to develop various novel functionalized MOF materials for rapid and excellent recovery of U(vi) from aqueous medium, along with selective sensing has been demonstrated in the present study. In this connection, a set of four distinct post synthetically modified (PSM) iso-reticular metal organic frameworks were synthesized from IRMOF-3 namely, IRMOF-PC (2-pyridine carboxaldehyde), IRMOF-GA (glutaric anhydride), IRMOF-SMA (sulfamic acid), and IRMOF-DPC (diphenylphosphonic chloride) for the recovery and sensing of U(vi) from aqueous medium. The MOFs were characterized by Fourier transform infrared spectroscopy (FTIR), powder XRD, BET surface area analysis, thermogravimetric analysis (TGA), NMR (13C, 1H and 31P), Scanning Electron Microscopy (SEM), and energy dispersive X-ray spectroscopy (EDX). Among all MOFs, post synthetically modified IRMOF-SMA showed enhanced thermal stability of about 420 °C. The MOFs were investigated for U(vi) sorption studies using a batch technique. All the MOFs exhibit excellent sorption capacity towards U(vi) (>90%) and maximum uptake was observed at pH 6. Sorption capacity of MOFs have the following order; IRMOF-3-DPC (300 mg U g−1) > IRMOF-SMA (292 mg U g−1) > IRMOF-PC (289 mg U g−1) > IRMOF-GA (280 mg U g−1) > IRMOF-3 (273 mg U g−1). IRMOF-DPC shows rapid sorption of uranium within 5 min with excellent uptake of U(vi) (>99%). The desorption of U(vi) was examined with different eluents and 0.01 M HNO3 was found to be most effective. The fluorescence sensing studies of U(vi) via IRMOF-3 and its PSM MOFs revealed high sensitivity and selectivity towards U(vi) over other competing rare earth metal ions (La3+, Ce4+, Sm3+, Nd3+, Gd3+, and Eu3+), wherein IRMOF-GA displayed an impressive detection limit of 0.36 mg L−1 for U(vi).

Four IRMOFs following PSM strategy were prepared. The MOFs were characterized by different techniques and were investigated for U(vi) sorption. PSM MOFs displayed impressive fluorescent sensing and selectivity of U(vi) over competing metal ions.  相似文献   
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Fenvalerate (Fen) is a synthetic pyrethroid, which is commonly used for destroying a variety of insect pests damaging several vegetable, fruit, and cotton crops. This insecticide is also used to mitigate household insects like flies, cockroaches, mosquitoes, and so forth. Human beings are exposed to formulated Fen preparations mostly by inhalation during spraying in fields for crop protection, for control of household insects, and also during handling and packaging at manufacturing plants. Limited online information is available regarding toxic effects of formulated Fen exposure on mammalian reproductive system. The present study has been undertaken to investigate male reproductive toxic effects of a formulated preparation of Fen (20% EC) particularly in relation to steroidogenic alterations in testes and sera of rats exposed by nose-only inhalation for (4 hours/day and five days a week) for three months. The results indicate significant reduction in the weight of testes, epididymal sperm counts, and sperm motility, along with decrease in marker testicular enzymes for testosterone biosynthesis viz. 17-beta-hydroxy steroid dehydrogenase (17-beta-HSD) and glucose-6-phosphate dehydrogenase (G6PDH), leading to net decrease in serum testosterone concentration in group of rats exposed to one-fifth LC50 of Fen (20% EC) by inhalation (4 hours/day, five days a week) subchronically for three months. These results for the first time indicate the role of testosterone in Fen (20% EC)-induced male reproductive toxicity of rats subchronically exposed by inhalation probably due to neuroendocrine-mediated phenomenon and hormone-disrupting property of the insecticide.  相似文献   
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We reviewed our experience of 25 children with adrenocortical tumours from January 1980 to December 1994. Their ages ranged from 7 months to 15 years; there were 16 girls and 9 boys. Truncal obesity, moon facies, hypertension, and virilisation were the most common clinical features. Establishment of the diagnosis of Cushing's syndrome was accomplished by hormonal and radiological studies. Eighteen patients had adrenocortical carcinomas, but 2 of them refused operation; 7 had adrenocortical adenomas. Twenty-three patients were treated by surgery; 6 with carcinomas are still alive after periods of 6 months to 3 years. The results of treatment of adrenocortical carcinoma have been poor, but the prognosis is excellent for benign lesions.  相似文献   
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