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71.
Cevikol C Karaali K Senol U Kabaalioğlu A Apaydin A Saba R Lüleci E 《European radiology》2003,13(1):141-148
Our objective was to describe MR imaging findings of liver lesions in human fascioliasis. The MR imaging of the liver was
performed in 29 patients with fascioliasis. Seventeen patients were women and 12 were men, with a mean age of 47.5 years (age
range 17–75 years). Hepatic lesions were grouped into five types based on their signal characteristics. Three patients had
normal imaging findings. One or more lesions were observed in the other 26 patients. The lesion types and the frequency of
appearances were as follows: hyperintensity of the liver capsule on T2-weighted images (n=16, 55.2%); ill-defined slightly hyperintense areas on T2-weighted images (n=18, 62.1%); lesions which were hypointense on T1-weighted and hyperintense on T2-weighted images (n=10, 34.5%); hypointense on T1-weighted images and centrally hypo- or hyperintense, surrounded by peripherally less hyperintense
area on T2-weighted images (n=4, 13.8%); and hypointense foci or ill-defined hypointense areas on T1- and T2-weighted images (n=10, 34.5%). We describe the MR imaging features of the disease. Our findings may help the differential diagnosis in which
fascioliasis should be added to the list.
Electronic Publication 相似文献
72.
The role of reactive oxygen species and apoptosis in the pathogenesis of varicocele in a rat model and efficiency of vitamin E treatment 总被引:4,自引:0,他引:4
Cam K Simsek F Yuksel M Turkeri L Turker L Haklar G Yalcin S Akdas A 《International journal of andrology》2004,27(4):228-233
We investigated role of reactive oxygen species (ROS) and apoptosis in the pathogenesis of infertility in experimental model of varicocele. The protective effect of vitamin E was also examined. Three groups of rats were constructed as the first group had sham operation, experimental varicoceles were established by partial ligation of the left renal vein in later two groups. Third group had received vitamin E. Production of ROS was determined by chemiluminescence assay (CL). The in situ end labelling technique was utilized to investigate apoptosis. Tissue vitamin E levels were measured by high performance liquid chromatography. The differences between luminol enhanced CL levels of groups were not statistically significant. However, the difference between CL levels of lucigenin probe in left testicles of sham and varicocele groups were statistically significant ( p = 0.0007). Similarly, the results of the third group receiving vitamin E significantly differed from the varicocele group ( p = 0.0025). The difference of apoptotic index was also statistically significant between sham and varicocele groups ( p = 0.0038). Although the values of apoptotic index detected in the vitamin E group were lower compared with the varicocele group, the difference was not significant. This study proposes that ROS production and apoptosis in the testicles were induced with experimental varicocele. Vitamin E had a protective role. An increased rate of apoptosis with experimental varicocele suggests a molecular alteration, which may involve ROS overproduction as the triggering mechanism. Consequently, this study indicates an association between varicocele and infertility at molecular level through stimulation of ROS and apoptosis. 相似文献
73.
Pierre-Gilles Henry Malgorzata Marjanska Jamie D Walls Julien Valette Rolf Gruetter Kamil Ugurbil 《Magnetic resonance in medicine》2006,55(2):250-257
Proton-observed carbon-edited (POCE) NMR spectroscopy is commonly used to measure 13C labeling with higher sensitivity compared to direct 13C NMR spectroscopy, at the expense of spectral resolution. For weakly coupled first-order spin systems, the multiplet signal at a specific proton chemical shift in POCE spectra directly reflects 13C enrichment of the carbon attached to this proton. The present study demonstrates that this is not necessarily the case for strongly coupled second-order spin systems. In such cases NMR signals can be detected in the POCE spectra even at chemical shifts corresponding to protons bound to 12C. This effect is demonstrated theoretically with density matrix calculations and simulations, and experimentally with measured POCE spectra of [3-13C]glutamate. 相似文献
74.
Manipulation of image intensity distribution at 7.0 T: passive RF shimming and focusing with dielectric materials 总被引:1,自引:0,他引:1
Yang QX Mao W Wang J Smith MB Lei H Zhang X Ugurbil K Chen W 《Journal of magnetic resonance imaging : JMRI》2006,24(1):197-202
PURPOSE: To investigate the effects of high dielectric material padding on RF field distribution in the human head at 7.0 T, and demonstrate the feasibility and effectiveness of RF passive shimming and focusing with such an approach. MATERIALS AND METHODS: The intensity distribution changes of gradient-recalled-echo (GRE) and spin-echo (SE) images of a human head acquired with water pads (dielectric constant = 78) placed in specified configurations around the head at 7.0 T were evaluated and compared with computer simulation results using the finite difference time domain (FDTD) method. The contributions to the B(1) field distribution change from the displacement current and conductive current of a given configuration of dielectric padding were determined with computer simulations. RESULTS: MR image intensity distribution in the human head with an RF coil at 7.0 T can be changed drastically by placing water pads around the head. Computer simulations reveal that the high permittivity of water pads results in a strong displacement current that enhances image intensity in the nearby region and alters the intensity distribution of the entire brain. CONCLUSION: The image intensity distribution in the human head at ultra-high field strengths can be effectively manipulated with high permittivity padding. Utilizing this effect, the B(1) field inside the human head of a given RF coil can be adjusted to reduce the B(1) field inhomogeneity artifact associated with the wave behavior (RF passive shimming) or to locally enhance the signal-to-noise ratio (SNR) in targeted regions of interest (ROIs; RF field focusing). 相似文献
75.
Kamil W Al Habashneh R Khader Y Al Bayati L Taani D 《Journal of periodontal research》2011,46(5):616-621
Kamil W, Al Habashneh R, Khader Y, Al Bayati L, Taani D. Effects of nonsurgical periodontal therapy on C‐reactive protein and serum lipids in Jordanian adults with advanced periodontitis. J Periodont Res 2011; 46: 616–621. © 2011 John Wiley & Sons A/S Background and Objective: Data on whether periodontal therapy affects serum CRP levels are inconclusive. The aim of this study was to determine if nonsurgical periodontal therapy has any effect on CRP and serum lipid levels in patients with advanced periodontitis. Material and Methods: Thirty‐six systemically healthy patients, ≥ 40 years of age and with advanced periodontitis, were recruited for the study. Patients were randomized consecutively to one of two groups: the treatment group (n = 18) or the control group (n = 18). Treated subjects received nonsurgical periodontal therapy, which included oral hygiene instructions and subgingival scaling and root planing. Systemic levels of inflammatory markers [C‐reactive protein (CRP) and the lipid profile] were measured at baseline and 3 mo after periodontal therapy. Results: Nonsurgical periodontal therapy in the treatment group resulted in a significant reduction in the serum CRP level. The average CRP level decreased from 2.3 mg/dL at baseline to 1.8 mg/dL (p < 0.005) after 3 mo of periodontal therapy. The average reduction (95% confidence interval) in CRP was 0.498 (95% confidence interval = 0.265–0.731). In the treatment group, the reduction in CRP was significantly, linearly and directly correlated with the reduction in the plaque index, the gingival index and the percentage of sites with pocket depth ≥ 7 mm (Pearson correlation coefficient = 0.746, 0.425 and 0.621, respectively). Nonsurgical periodontal therapy had no effect on the lipid parameters. Conclusion: This study demonstrated that nonsurgical periodontal therapy results in a significant reduction in the serum CRP level. The effect of this outcome on systemic disease is still unknown. 相似文献
76.
Qing X Yang Jinghua Wang Christopher M Collins Michael B Smith Xiaoliang Zhang Kamil Ugurbil Wei Chen 《Magnetic resonance in medicine》2004,52(5):1016-1020
A phantom design method suitable for high-field MRI based on the RF field wave characteristics of sample and experimental validations at 7.0 T and 3.0 T are presented. The RF field distribution in a phantom with a given RF coil system is primarily determined by the sample size relative to the wavelength inside the sample, and the ratio between the displacement and conduction currents. Experimental results demonstrate that the MR image intensity patterns associated with wave behavior in human samples at a given field strength can be reproduced with a phantom at the same or different field strengths once the dimension and penetration constant are scaled by the corresponding wavelength in the sample medium. 相似文献
77.
Mehmet Odabasi Cengiz Eris Mehmet Kamil Yildiz Hasan Abuoglu Sami Akbulut Abdullah Saglam 《International surgery》2013,98(3):277-281
Hepatic artery aneurysms are responsible for 12% to 20% of all visceral arterial aneurysms. Because most patients are asymptomatic, this disease is generally diagnosed incidentally during radiologic examination. Aneurysm rupture develops in 14% to 80% of cases, depending on the aneurysmatic segment''s diameter and location, as well as other etiologic factors. Mortality rates associated with rupture range between 20% and 70%. Thus, early diagnosis and timely initiation of medical interventions are critical to improve survival rates. Here, we present a male patient, age 69 years, with a hepatic artery aneurysm that was detected incidentally. The 3-cm aneurysm was detected on contrast-enhanced computed tomography and extended from the common hepatic artery to the hepatic trifurcation. A laparotomy was performed using a right subcostal incision. After dissection of the hepatoduodenal ligament, the common, right, and left hepatic arteries, as well as the gastroduodenal artery, were suspended separately. Then, the aneurysmatic hepatic artery segment was resected, and the gastroduodenal artery stump was ligated. An end-to-end anastomosis was formed between the left and common hepatic arteries, followed by an end-to-end anastomosis formed between the right hepatic artery and splenic artery using a splenic artery transposition graft. Postoperative follow-up examinations showed that both hepatic arterial circulations were good, and no splenic infraction had developed. 相似文献
78.
79.
Michael A. Flierl Brian M. Culp Kamil T. Okroj Bryan D. Springer Brett R. Levine Craig J. Della Valle 《The Journal of arthroplasty》2017,32(8):2505-2507
Background
One proposed strategy to increase the success of irrigation and debridement with implant retention for the treatment of acute periprosthetic joint infection (PJI) is the use of dissolvable antibiotic-impregnated calcium sulfate beads to provide a local depot of antibiotics. The purpose of this study was to evaluate the outcome of such an approach.Methods
Thirty-two patients with acute hematogenous (18 patients; 1 bilateral) or acute postoperative (14 patients) PJIs who underwent irrigation and debridement with implant retention and addition of antibiotic-impregnated calcium sulfate beads were retrospectively reviewed. PJI followed 27 total knee arthroplasties and 6 total hip arthroplasties. The most common infecting organisms were methicillin-sensitive Staphylococcus aureus (13 of 33) and Streptococcus (9 of 33). The primary outcome parameter was recurrence of infection according to the Musculoskeletal Infection Society criteria. Patients were followed up for a minimum of 3 months or until failure.Results
At a mean of 12.7 months (range, 3-30 months), 16 of the 33 patients failed (48%). Acute hematogenous and acute postoperative PJI had similar failure rates at 47% and 50%, respectively (P = .88). Seven failures required a 2-stage exchange, while 8 patients were treated with chronic antibiotic suppression, being unwilling or unable to undergo further surgical intervention.Conclusion
The addition of antibiotic-impregnated calcium sulfate beads does not appear to improve outcomes of irrigation and debridement with implant retention in the setting of acute hematogenous or acute postoperative PJI. Given the short follow-up in this report, this represents a best-case scenario and the overall failure rate may be higher with further follow-up. 相似文献80.
Inflammatory Markers and Risk of Hip Fracture in Older White Women: The Study of Osteoporotic Fractures 下载免费PDF全文
Kamil E Barbour Li‐Yung Lui Kristine E Ensrud Teresa A Hillier Erin S LeBlanc Steven W Ing Marc C Hochberg Jane A Cauley for the Study of Osteoporotic Fractures Research Group 《Journal of bone and mineral research》2014,29(9):2057-2064
Hip fractures are the most devastating consequence of osteoporosis and impact 1 in 6 white women leading to a two‐ to threefold increased mortality risk in the first year. Despite evidence of inflammatory markers in the pathogenesis of osteoporosis, few studies have examined their effect on hip fracture. To determine if high levels of inflammation increase hip fracture risk and to explore mediation pathways, a case‐cohort design nested in a cohort of 4709 white women from the Study of Osteoporotic Fractures was used. A random sample of 1171 women was selected as the subcohort (mean age 80.1 ± 4.2 years) plus the first 300 women with incident hip fracture. Inflammatory markers interleukin‐6 (IL‐6) and soluble receptors (SR) for IL‐6 (IL‐6 SR) and tumor necrosis factor (TNF SR1 and TNF SR2) were measured, and participants were followed for a median (interquartile range) of 6.3 (3.7, 6.9) years. In multivariable models, the hazard ratio (HR) of hip fracture for women in the highest inflammatory marker level (quartile 4) was 1.64 (95% confidence interval [CI], 1.09–2.48, p trend = 0.03) for IL‐6 and 2.05 (95% CI, 1.35–3.12, p trend <0.01) for TNF SR1 when compared with women in the lowest level (quartile 1). Among women with 2 and 3–4 inflammatory markers in the highest quartile, the HR of hip fracture was 1.51 (95% CI, 1.07–2.14) and 1.42 (95% CI, 0.87–2.31) compared with women with zero to one marker(s) in the highest quartile (p trend = 0.03). After individually adjusting for seven potential mediators, cystatin‐C (a biomarker of renal function) and bone mineral density (BMD) attenuated HRs among women with the highest inflammatory burden by 64% and 50%, respectively, suggesting a potential mediating role. Older white women with high inflammatory burden are at increased risk of hip fracture in part due to poor renal function and low BMD. © 2014 American Society for Bone and Mineral Research. 相似文献