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Amorphous silica that was extracted from rice husk was used to synthesize the magMCM-41 mesoporous silica. This was then functionalized by the APTMS group in order to produce NH2-magMCM-41 as a novel and low–cost adsorbent. The XRD, VSM, N2 adsorption–desorption, FT–IR, TGA, SEM and TEM analyses were utilized to characterize the produced materials. In order to optimize the adsorption of the Pb(II) ions, the RSM (response surface methodology) was applied by using the synthesized adsorbent in aqueous solutions. A rotatable CCD (central composite design) was adopted to carry out the experiments and RSM was used to analyze them. Three independent factors namely, initial solution pH (3–7), adsorbent dosage (0.1–2 g L?1), and initial Pb(II) concentration (15–150 mg L?1) were used to investigate the removal procedure. According to the obtained results, the initial solution pH of 5.22, adsorbent dosage of 0.1 g L?1, and initial Pb(II) concentration of 150 mg L?1 were considered as the optimum conditions with 64.32% removal of Pb(II) and an adsorption capacity of 540.64 mg g?1. The maximum removal efficiency of Pb(II) ions was found to be 96.76%. The Sips isotherm model represents a better correlation with equilibrium data. It was reported by the kinetic study that data taken from the experiments fitted better to the pseudo–second–order model compared to the pseudo–first–order and intraparticle diffusion models. Finally, according to the thermodynamic study, the removal process strongly depends on temperature, which indicates an exothermic behavior and spontaneous nature of the adsorption. 相似文献
83.
Ali R. Cohen Thomas J.E. Clark Lynette M. Renner Pamela C. Carter Erin M. Shriver 《Canadian journal of ophthalmology. Journal canadien d'ophtalmologie》2019,54(3):355-358
ObjectiveDetermine the prevalence of intimate partner violence (IPV) as a mechanism of traumatic ocular injury in women, typical injury patterns, and the clinical course of affected patients. Encourage IPV screening and safety assessment in patients presenting with characteristic ocular trauma.MethodsMedical records of 211 female patients with traumatic ocular injuries evaluated at the University of Iowa Hospitals and Clinics between January 1995 and January 2015 were reviewed to determine the rate of IPV as a mechanism of ocular trauma. Twenty-one patients were excluded due to no documented trauma.ResultsLeading causes of traumatic ocular injuries in the 190 female patients included were accidental trauma with an inanimate object (n = 70/190, 36.8%), falls (n = 52/190, 27.4%), motor vehicle collisions (n = 21/190, 11.1%), and assault (n = 16/190, 8.4%). In 2.1% of cases (n = 4/190), no mechanism of traumatic injury was documented. Assault was the fourth leading mechanism of injury accounting for 8.4% of cases (n = 16/190), with IPV accounting for more than one third of cases with a documented perpetrator (n = 5/13). No perpetrator was documented in 18.8% (n = 3/16). All 5 patients with IPV-related injuries sustained scleral laceration or rupture; 4 out of 5 patients had no light perception vision and ultimately required enucleation.ConclusionIPV is an important mechanism of traumatic ocular injury. IPV-associated injuries tend to be severe in nature, as demonstrated by the high rate of globe laceration or rupture and subsequent enucleation in the study population. By appropriate screening and referral, ophthalmologists have an opportunity to redirect a potentially devastating course. 相似文献
84.
Fahad Ali Rahul Smita Jyoti Ambreen Fatima Saba Khanam Falaq Naz Yasir Hasan Siddique 《Scientia pharmaceutica》2016,84(2):361-377
The present investigation was aimed at studying the possible role of curcumin against N-nitrosodiethylamine (NDEA)-induced toxicity in albino rats. Administration of NDEA to rats at a concentration of 0.1 mg/ml in drinking water ad libitum for 21 days produced toxicity in them, which was evident from histopathological changes in the rat livers, and increased levels of blood serum enzyme markers, i.e. aspartate transaminase, alanine transaminase, alkaline phosphatase, and lactate dehydrogenase. In addition, the levels of oxidative stress markers like lipid peroxidation (LPO), protein carbonyl (PCC), and glutathione-S-transferase (GST) activity were elevated and the total glutathione (GSH) content was reduced in the livers. The administration of curcumin to rats at concentrations of 10, 20, and 40 mg/ml in drinking water along with 0.1 mg/ml of NDEA for 21 days effectively suppressed NDEA-induced toxicity and also resulted in a dose-dependent reduction in the levels of blood serum enzyme markers (AST, ALT, ALP, and LDH). Moreover, LPO, PCC, and GST activity were reduced and the GSH level was increased upon the administration of curcumin along with NDEA. The results obtained for the comet assay in rat hepatocytes and blood lymphocytes showed a significant dose-dependent decrease in the mean tail length. The micronucleus assay performed on rat hepatocytes also showed a dose-dependent reduction in the frequency of micronucleated cells along with curcumin administration. These results suggest that curcumin has a protective role against NDEA-induced toxicity in albino rats. 相似文献
85.
Dunia Alarkawi M Sanni Ali Dana Bliuc Natalia Pallares Cristian Tebe Leena Elhussein Fergus J Caskey Nigel K Arden Yoav Ben-Shlomo Bo Abrahamsen Adolfo Diez-Perez Julio Pascual María José Pérez-Sáez Jacqueline R Center Andrew Judge Cyrus Cooper Muhammad K Javaid Daniel Prieto-Alhambra 《Journal of bone and mineral research》2020,35(5):894-900
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Ahmad Habeeb Hattab Dala Ali Alani Bassam Abdul Rasool Hassan Azyyati Mohd Suhaimi Ali Haider Mohammed 《Osong Public Health and Research Perspectives》2020,11(6):373
ObjectivesThis study aimed to assess medication use in pregnant women in Malaysia by measuring use, knowledge, awareness, and beliefs about medications.MethodsThis was an observational, cross-sectional study involving a total of 447 pregnant women who attended the Obstetrics and Gynecology Clinic, Hospital Kuala Lumpur (HKL), Malaysia. A validated, self-administered questionnaire was used to collect participant data.ResultsMost of pregnant women had taken medication during pregnancy and more than half of them (52.8%) showed a poor level of knowledge about the medication use during pregnancy. Eighty-three percent had a poor level of awareness and 56.5% had negative beliefs. Age and education level were significantly associated with the level of knowledge regarding medication use during pregnancy. Multiparous pregnant women, and pregnant women from rural areas were observed to have a higher level of awareness compared with those who lived in urban areas. Use of medication during pregnancy was determined to be significantly associated with education level, and race.ConclusionAlthough there was prevalent use of medication among pregnant women, many had negative beliefs, and insufficient knowledge and awareness about the risks of taking medication during pregnancy. Several sociodemographic characteristics were significantly associated with the use (race and education level), level of knowledge (age and education level), awareness (parity and place of residence), and beliefs (race, education level, and occupation status) towards medication use during pregnancy. 相似文献
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Inflammation in the liver is an extraintestinal manifestation that is frequently seen during inflammatory bowel diseases (IBD). The authors investigated histopathologycal, ultrastructural and antioxidant effects of dexmedetomidine (Dex) on liver during trinitrobenzene sulfonic acid (TNBS)-induced inflammatory bowel disease. Thirty-two BALB/c mice were divided (n?=?8) as follows: control; Dex (dexmedetomidine) (30?μg/kg) for 6 days; TNBS 150?μL, TNBS?+?ethanol (50% w/v) intrarectally; TNBS?+?Dex. The histopathological and ultrastructural changes were evaluated. The levels of malondialdehyde (MDA), activity of antioxidant enzymes (GPx and SOD) were measured in liver tissue. Induction of colitis induced histopathological and ultrastructural changes of damage in liver. Those changes were markedly reduced in the TNBS?+?Dex group and that reduction was even significant in comparison to the TNBS group. MDA levels were significantly higher in the TNBS group and dexmedetomidine significantly elevated SOD levels in the TNBS?+?Dex group. These results suggest that the administration of dexmedetomidine reduces the histopathological and ultrastructural damage and increases the defense capacity against oxidative damage on liver in this IBD mice model. 相似文献