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排序方式: 共有684条查询结果,搜索用时 46 毫秒
31.
Annisa Luthfiah Muhamad Diki Permana Yusi Deawati M. Lutfi Firdaus Iman Rahayu Diana Rakhmawaty Eddy 《RSC advances》2021,11(61):38528
The entries of pathogenic bacteria into the human body remain a severe problem to health that can be prevented using antibacterial agents. Meanwhile, the photocatalytic technique using semiconductor nanocomposite TiO2–SiO2 has great potential as an antibacterial method. In order to utilize natural resources, SiO2 supporting materials are obtained from the extraction of beach sand due to the high silica content. Therefore, this study aims to synthesize a nanocomposite of TiO2 with SiO2 extracted from beach sand as an antibacterial agent against Staphylococcus aureus and Pseudomonas aeruginosa. The antibacterial activity test used the dilution and optical density method. Based on XRD analysis, the crystals of TiO2 in the synthesized composites showed a more dominant anatase structure. Furthermore, Ti–O–Si bonds were identified from the IR spectrum, which showed the interaction between TiO2 and SiO2. In addition, SEM-EDX results showed agglomerated spherical particles with a TiO2–SiO2 nanocomposite particle size of 40–107 nm. The best antibacterial activity was demonstrated by the 1 : 0.5 TiO2–SiO2 nanocomposite, with inactivation percentages of S. aureus and P. aeruginosa of 98.69% and 97.44%, respectively.TiO2 material is composited with silica obtained from natural sand with indirect sonochemistry method. The addition of SiO2 increase the photocatalyst activity of TiO2 as an antibacterial against S. aureus and P. aeruginosa. 相似文献
32.
Simşek T Eroglu L Engin MS Kaplan S Yildiz L 《Journal of reconstructive microsurgery》2006,22(8):631-640
This paper reports a continuous horizontal mattress suture technique with advantages such as decreased time for anastomosis, minimized anastomotic leakage, eversion around the vessel edges, and other advantages which the continuous anastomosis technique has. This technique was compared with the classical interrupted and classical continuous suture techniques on a total of 59 Sprague-Dawley rat common carotid arteries: Group 1 (n = 19), interrupted suture technique; Group 2 (n = 20), standard continuous technique, and Group 3 (n = 20), continuous horizontal mattress technique. Early (30 min) and late (21 days) patency rates, anastomosis time, leakage on clamp release, oozing duration, additional sutures needed, and total number of sutures placed were statistically compared between groups. Specimens were taken at the 21st day randomly, and light microscopy (LM), scanning electron microscopy (SEM), and angiographic studies were performed. Results revealed that the continuous mattress suture technique has the advantages of providing a water-tight anastomosis with less suture materials in a shorter time, and minimal intraluminal suture material which can incite thrombosis. On the other hand, a tendency to anastomotic stricture was found to be the sole disadvantage of this technique. 相似文献
33.
Senem Yaman Tunc Elif Agacayak Sibel Sak Serdar Basaranoglu Neval Yaman Goruk Abdulkadir Turgut 《The journal of maternal-fetal & neonatal medicine》2017,30(6):739-744
Objective: The aim of the present study is to evaluate the effects of the increased number of caesarean deliveries (CDs) in cases of multiple repeat caesarean deliveries (MRCDs) on maternal and neonatal morbidity.Methods: MRCDs admitted to our hospital between January 2013 and September 2014 were analysed retrospectively. A total number of 1133 women were included in the study and were divided into 4 groups. Group 1: second CDs (n?=?329); Group 2: third CDs (n?=?225); Group 3: fourth CDs (n?=?447); Group 4: fifth CDs (n?=?132). The clinical, demographic, intraoperative and postoperative data of the patients were registered upon the review of patient files.Results: The differences among the groups were found to be statistically significant in terms of mean maternal age, gravida, APGAR (Activity, Pulse, Grimace, Appearance, Respiration) scores, hospital stay and operation time. In addition, the difference was also statistically significant for severe adhesion, bladder injury and premature birth. No statistically significant difference was observed among the groups with respect to placenta previa, placenta accreta, caesarean hysterectomy, uterine scar rupture.Conclusions: According to our findings, MRCDs seem to increasing the maternal and neonatal morbidity even though they are not life-threatening. 相似文献
34.
Didem Yazi Tunc Akkoc Cevdet Ozdemir Ozlem Yesil Metin Aydogan Recep Sancak Nerin N Bahceciler Isil B Barlan 《Annals of allergy, asthma & immunology》2007,98(6):573-579
BACKGROUND: Mycobacteria are being investigated for modulation of inflammation in asthma and atopic disorders by eliciting particularly strong protective TH1 immune responses. OBJECTIVE: To investigate the long-term effects of intratracheally administered Mycobacterium vaccae on an experimental murine model of asthma. METHODS: BALB/c mice were placed in 4 groups: long-term M. vaccae, M. vaccae, asthma, and control groups. All groups but controls were sensitized intraperitoneally and challenged intratracheally with ovalbumin. The long-term M. vaccae and M. vaccae groups were treated with M. vaccae intratracheally simultaneously during challenges. Finally, mice in the long-term M. vaccae group were rechallenged with ovalbumin nebulization 24 days later. Evaluations of lung histopathologic findings and serum cytokine levels were performed. RESULTS: Comparison of the long-term M. vaccae group with the asthma model group revealed that the number of hyperplasic goblet cells in small and large airways (small airway: P < .05; large airways: P < .01) and thickness of basement membrane in large airways were significantly less in the long-term M. vaccae group. Furthermore, numbers of hyperplasic goblet cells in small airways (P < .05) and basement membrane in the large airway (P < .05), as well as inflammation in small airways (P < .01), were significantly less in the M. vaccae group when compared with the asthma model group. Interferon-gamma secretion from splenocytes of the M. vaccae group was significantly higher than the asthma model and long-term M. vaccae groups. CONCLUSION: Intratracheal administration of M. vaccae exerted a long-lasting ameliorating effect on airway histopathologic features of a murine asthma model. 相似文献
35.
Balik E Eren T Bugra D Buyukuncu Y Akyuz A Yamaner S 《Clinics (S?o Paulo, Brazil)》2011,66(11):1935-1941
OBJECTIVE:
To compare the surgical outcomes of stapled and handsewn closures in loop ileostomies.METHODS:
The data of 225 patients requiring loop ileostomies from 2002 to 2007 were retrospectively evaluated. The patients underwent partial small-bowel resections and either handsewn or stapled anastomoses for the ileostomy closures. They were followed up postoperatively with routine surgical examinations.RESULTS:
The study group consisted of 124 men and 101 women with a mean age of 49.12 years. The ileostomy closure was performed with handsewn in 129 patients and with stapled in 96 patients. The mean time to the first postoperative flatus was 2.426 days in the handsewn group and 2.052 days in the stapled group (p<0.05). The mean time to the first postoperative defecation was 3.202 days in the handsewn group and 2.667 days in the stapled group (p<0.05). The mean duration of patient hospital stay was 8.581 days for the handsewn group and 6.063 days for the stapled group (p<0.05).CONCLUSIONS:
Patients who underwent ileostomy closure with stapled recovered faster in the postoperative period and required shorter hospital stays than those whose closures were performed with handsewn. In our opinion, stapled should be considered the gold standard for loop ileostomy closures. 相似文献36.
Evaluation of the functions of the parvocellular and magnocellular pathways in strabismic amblyopia 总被引:2,自引:0,他引:2
Demirci H Gezer A Sezen F Ovali T Demiralp T Isoglu-Alkoc U 《Journal of pediatric ophthalmology and strabismus》2002,39(4):215-221
PURPOSE: To evaluate the functions of the magnocellular and parvocellular pathways in strabismic amblyopia. METHODS: Visual evoked potentials produced by achromatic and chromatic stimuli in 14 children with strabismic amblyopia were compared with those in 14 age-matched control subjects. The achromatic sine-wave grating with low spatial frequency was used to stimulate the magnocellular pathway, whereas the parvocellular pathway was stimulated by the chromatic sine-wave grating (isoluminant red-green) with low and high spatial frequencies. RESULTS: When the achromatic stimuli with low spatial frequency were used, the latencies of the N1 and P1 components and the amplitude of the N1-P1 complex were similar in the children with strabismic amblyopia and the control subjects. There also were no differences between the amblyopic and non-amblyopic eyes of the children with strabismic amblyopia. When chromatic stimuli with low and high spatial frequencies were used, the latencies of the N1 and P1 components were significantly longer and the amplitude of the N1-P1 complex was significantly smaller in the children with strabismic amblyopia than in the control group. When the amblyopic and non-amblyopic eyes of the children with strabismic amblyopia were compared, the latencies of the N1 and P1 components were longer and the amplitude of the N1-P1 complex was smaller in the amblyopic eyes. CONCLUSION: In strabismic amblyopia, the cells in the parvocellular pathway may be more involved, whereas the magnocellular pathway may be relatively spared. 相似文献
37.
Faruk Abike Ayse Basak Engin İlkkan Dunder Omer Lutfi Tapisiz Canan Aslan Lale Kutluay 《Archives of gynecology and obstetrics》2011,284(1):209-214
Objective
To investigate the relationship between human papilloma virus (HPV) infection persistence and serum folate, vitamin B12, homocysteine, neopterin levels in cervical dysplasia. 相似文献38.
van Dijk M Tunc DC Smit TH Higham P Burger EH Wuisman PI 《Journal of biomedical materials research》2002,63(6):752-759
The in vitro and in vivo degradation of poly-L-lactic acid cages used as an adjunct to spinal arthrodesis was investigated. In the in vitro experiments cages were subjected to aging up to 73 weeks in phosphate-buffered solution (pH 7.4) at 37 degrees C. Inherent viscosity, crystallinity, and mechanical strength were determined at different time points. In the in vivo study, the poly-L-lactic acid cages were packed with bone graft and implanted in the L3-L4 spinal motion segment of 18 Dutch milk goats. At 12, 26, and 52 weeks, the motion segments were isolated and poly-L-lactic acid samples retrieved. On evaluation, the in vivo implanted cages showed an advanced decline in inherent viscosity compared to the cages subjected to in vitro degradation experiments. At 6 months of implantation, the geometrical shape and original height of 10 mm was maintained during 6 months of follow up. This finding fits well with the observation that mechanical strength was maintained for a period of 6 months in vitro. At 12 months, the poly-L-lactic acid cage had been disintegrated into multiple fragments with signs of absorption. Despite the high-load-bearing conditions, the poly-L-lactic acid cage allowed interbody fusion to occur without collapse of the cage. 相似文献
39.
A 10-year-old girl presented with diabetic ketoacidosis, shock, and severe abdominal pain. She was found to have acute pancreatitis and acute kidney injury after shock resuscitation and severe persistent hypertriglyceridemia. The severe hypertriglyceridemia was treated with 1 course of plasmapheresis, which corrected the triglyceride level and was temporally associated with improvement of the abdominal pain and renal dysfunction. Diabetes is known to contribute to an elevated triglyceride level, especially in the setting of an underlying lipid disorder. However, no such disorders were found in this patient. To the best of our knowledge, this is the first report of a pediatric patient presenting with the triad of severe hypertriglyceridemia, diabetic ketoacidosis, and pancreatitis treated successfully with plasmapheresis. 相似文献
40.
The performance of digital radiography systems can be evaluated in terms of spatial resolution and noise. Noise plays an important role in the achievable image quality for detecting small and low-contrast structures in digital images created by these systems. Our aim in this study was to investigate the noise sources both in the spatial and frequency domain for three digital radiography systems, one digital fluoroscopy system, and one digital mammography system, and to obtain information about the effective operating dose range of these detectors. Noise evaluation in the spatial domain was done with the relative standard deviation–detector air kerma relationship evaluation method. The characterization of the noise in the spatial domain gives information about the types of noise, but does not give information about the noise power distribution in frequency space. Therefore, noise evaluation in the frequency domain was carried out by noise power spectrum measurement. The observed dominant noise component at lower detector doses was electronic noise for the digital mammography system, whereas structured noise was observed to make up nearly half of the total noise at higher detector doses for one of the digital radiography systems. The structured noise component was increased by use of a grid in these systems, independent of the grid ratio and grid frequency, but this increase was lower for higher grid frequencies. Furthermore, the structured noise coefficient was decreased with gain and offset calibrations. The five systems which we evaluated behaved as a quantum noise limited for clinically used detector doses. 相似文献