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41.
Handheld devices such as smartphones and tablets are becoming useful in the medical field, as they allow physicians, radiologists, and researchers to analyze images with the benefit of mobile accessibility. However, for handheld devices to be effective, the display must be able to perform well in a wide range of ambient illumination conditions. We conducted visual experiments to quantify user performance for testing the image quality of two current-generation devices in different ambient illumination conditions while measuring ambient light levels with a real-time illuminance meter. We found and quantified that due to the high reflectivity of handheld devices, performance deteriorates as the user moves from dark areas into environments of greater ambient illumination. The quantitative analysis suggests that differences in display reflection coefficients do not affect the low illumination performance of the device but rather the performance at higher levels of illumination. 相似文献
42.
Epidemiology of 11 respiratory RNA viruses in a cohort of hospitalized children in Riyadh,Saudi Arabia 下载免费PDF全文
Haitham M. Amer Mohamed S. Alshaman Mohamed A. Farrag Moawia E. Hamad Muslim M. Alsaadi Fahad N. Almajhdi 《Journal of medical virology》2016,88(6):1086-1091
43.
Bacteria or their products may cause chronic inflammation and subsequent bone loss. This inflammation and bone loss may be associated with significant morbidity in chronic otitis media, periodontitis, endodontic lesions, and loosening of orthopedic implants caused by lipopolysaccharide (LPS)-contaminated implant particles. Currently, it is not clear how bacteria or endotoxin-induced bone resorption occurs and what cell types are involved. Here we report that Porphyromonas gingivalis, a periodontal pathogen, and Escherichia coli LPS induce osteoclastic cell formation from murine leukocytes in the absence of osteoblasts. In contrast, stimulation with parathyroid hormone had no effect. These multinucleated, tartrate-resistant acid phosphatase-positive cells were positive for receptor activator of NF-kappaB (RANK), the receptor for osteoprotegerin ligand (OPGL), also known as RANK ligand (RANKL). Blocking antibodies demonstrated that their formation was dependent upon expression of OPGL and, to a lesser extent, on tumor necrosis factor alpha. Mononuclear cells represented a significant source of OPGL production. In vivo, P. gingivalis injection stimulated OPGL expression in both mononuclear leukocytes and osteoblastic cells. Thus, these findings describe a pathway by which bacteria could enhance osteolysis independently of osteoblasts and suggest that the mix of cells that participate in inflammatory and physiologic bone resorption may be different. This may give insight into new targets of therapeutic intervention. 相似文献
44.
Sharjeel Usmani Najeeb Ahmed Gopinath Gnanasegaran Rashid Rasheed Fahad Marafi Mashari Alnaaimi Mohammad Omar Ahmed Musbah Fareeda al Kandari Stijn De Schepper Tim Van den Wyngaert 《The British journal of radiology》2021,94(1120)
Objective:A new Bayesian penalized likelihood reconstruction algorithm for positron emission tomography (PET) (Q.Clear) is now in clinical use for fludeoxyglucose (FDG) PET/CT. However, experience with non-FDG tracers and in special patient populations is limited. This pilot study aims to compare Q.Clear to standard PET reconstructions for 18F sodium fluoride (18F-NaF) PET in obese patients.Methods:30 whole body 18F-NaF PET/CT scans (10 patients with BMI 30–40 Kg/m2 and 20 patients with BMI >40 Kg/m2) and a NEMA image quality phantom scans were analyzed using ordered subset expectation maximization (OSEM) and Q.Clear reconstructions methods with B400, 600, 800 and 1000. The images were assessed for overall image quality (IQ), noise level, background soft tissue, and lesion detectability, contrast recovery (CR), background variability (BV) and contrast-to-noise ratio (CNR) for both algorithms.Results:CNR for clinical cases was higher for Q.Clear than OSEM (p < 0.05). Mean CNR for OSEM was (21.62 ± 8.9), and for Q.Clear B400 (31.82 ± 14.6), B600 (35.54 ± 14.9), B800 (39.81 ± 16.1), and B1000 (40.9 ± 17.8). As the β value increased the CNR increased in all clinical cases. B600 was the preferred β value for reconstruction in obese patients. The phantom study showed Q.Clear reconstructions gave lower CR and lower BV than OSEM. The CNR for all spheres was significantly higher for Q.Clear (independent of β) than OSEM (p < 0.05), suggesting superiority of Q.Clear.Conclusion:This pilot clinical study shows that Q.Clear reconstruction algorithm improves overall IQ of 18F-NaF PET in obese patients. Our clinical and phantom measurement results demonstrate improved CNR and reduced BV when using Q.Clear. A β value of 600 is preferred for reconstructing 18F-NaF PET/CT with Q.Clear in obese patients.Advances in knowledge:18F-NaF PET/CT is less susceptible to artifacts induced by body habitus. Bayesian penalized likelihood reconstruction with18F-NaF PET improves overall IQ in obese patients. 相似文献
45.
Neetika Garg Cassandra D. Votruba Fahad Aziz Sandesh Parajuli Maha Mohamed Arjang Djamali Didier A. Mandelbrot 《Clinical transplantation》2020,34(8):e13999
Due to high prevalence of primary aldosteronism (PA) in the general hypertensive population, and its association with worse cardiovascular and renal outcomes, the 2016 Endocrine Society Guidelines explicitly recognize PA as a major public health issue requiring urgent attention. Its prevalence in hypertensive kidney transplant recipients (KTRs) is unknown. In this cross-sectional study, we screened KTRs with hypertension who were on ≥4 antihypertensive medications, on 3 antihypertensive medications with BP ≥ 140/90, and on potassium supplements, or were hypokalemic. 172 of 280 eligible patients successfully completed the testing. A positive screen for PA defined by an aldosterone-to-renin ratio of ≥20 and a plasma aldosterone concentration of >15 ng/dL yielded a prevalence of 15.7%. Potassium supplement requirement (52% vs 27%, P = .01) and hypokalemia (25.9% vs 4.8%, P < .01) were more common in patients who screened positive compared with those who screened negative. 67% of patients who screened positive were on potassium supplements and/or were hypokalemic. Our study is the first to systematically explore the prevalence of PA among the hypertensive KTR population, which has inherently high cardiovascular risk. Further studies are needed to determine the cardiovascular and renal risk attributable to PA, and define optimal therapy for KTRs with PA. 相似文献
46.
Introduction Umbilicus is an important surface landmark on the anterior abdominal wall in addition to its aesthetic and psychological effect. Objectives The objective of the study is to determine the position of umbilicus in Iraqi adults to provide a guide for the neoumbilicus in abdominoplasty. Subjects and Methods This is an observational study performed on 100 volunteers with no abdominal wall abnormality. Measurements included weight, height, body mass index (BMI), distance from xiphoid to umbilicus, distance from xiphoid process to pubic symphysis, distance from xiphoid process to both anterior superior iliac spine (ASIS), distance from pubic symphysis to umbilicus and from pubic symphysis to xiphisternum, distance of umbilicus to both ASIS, and distance of umbilicus to interspinous line and to inter-anterior hypochondrium line. Results The study included 100 volunteers, with 50% male and 50% female whose age ranges between 18 to 60 years. The results were a follows: distance from xiphoid process to umbilicus and distance from xiphoid process to pubic symphysis were 18.03 ± 3.25 cm and 32.21 ± 4.64 cm, respectively; distances from xiphoid process to right ASIS and left ASIS were 25.95 ± 5.72 cm and 25.84 ± 6.02 cm, respectively; distance from pubic symphysis to umbilicus was 17.66 ± 3.12 cm; distance of umbilicus to interspinous line was 9.25 ± 1.84 cm. The distance from umbilicus to inter anterior hypochondrium line was 9.905 ± 2.19 cm. Conclusion These measurements can determine the neoumbilicus position, reduce practical mistakes, and improve postsurgical outcomes. 相似文献
47.
Moazam Javed Muhammad Tarique Tunio Hafiz Abdul Rauf Muhammad Fahad Bhutta Sadia Naz Sajid Iqbal 《Andrologia》2019,51(8)
The aim of the present study was to determine the protective effects of pomegranate juice in tris‐based extender on semen parameters, computer‐assisted sperm analysis (CASA) motion characteristics and field fertility of post‐thawed Nili Ravi buffalo (Bubalus bubalis) bull spermatozoa. Two consecutive ejaculates/collection from each of the five adult Nili Ravi buffalo bulls were collected with artificial vagina at 42°C for a period of 7 weeks, diluted in extender containing different concentrations of pomegranate juice (0.0%, 2.5%, 5%, 7.5% and 10%). Diluted samples were packed and frozen in 0.54 ml French straws. The addition of 10% pomegranate juice in extender significantly improved post‐thaw sperm morphology (%), motilities (CASA total motility, progressive motility (%) as well as VAP, VSL, VCL, STR, DAP, DSL) compared to the control group (p < 0.05). Plasma membrane, acrosome membrane and DNA integrity were significantly higher in extender with 10% pomegranate juice than the control group (p < 0.05). Field fertility rate (60.39% vs. 46.53%) was higher (p < 0.05) in extender with 10% pomegranate juice as compared to the control. It is therefore concluded that the addition of 10% pomegranate juice in tris‐based extender improves post‐thaw semen parameters, CASA motion dynamics and field fertility in Nili Ravi buffaloes. 相似文献
48.
Mousa A. Khoursheed Ibtisam A. Al-Bader Fahad S. Al-asfar Ali I. Mohammad Mumtaz Shukkur Hussain M. Dashti 《Obesity surgery》2011,21(8):1157-1160
Bariatric surgery for morbid obesity has been established as an effective treatment method and has been shown to be associated
with resolution of co-morbidities. Despite its success, some patients may require revision because of weight regain or mechanical
complications. From September 2005 to December 2009, 42 patients underwent revisional Roux-en-Y gastric bypass (RYGB). All
procedures were performed by one surgeon. Demographics, indications for revision, complications, and weight loss were reviewed.
Thirty-seven patients were treated with laparoscopic (n = 36) or open (n = 1) RYGB after failed laparoscopic adjustable gastric banding. Four patient were treated with laparoscopic (n = 3) or open (n-1) RYGB after failed vertical banded gastroplasty, and one patient underwent open redo RYGB due to large
gastric pouch. Conversion rate from laparoscopy to open surgery was 2.5% (one patient). Mean operative time was 145.83 ± 35.19 min,
and hospital stay was 3.36 ± 1.20 days. There was no mortality. Early and late complications occurred in six patients (14.2%).
The mean follow-up was 15.83 ± 13.43 months. Mean preoperative body mass index was 45.15 ± 7.95 that decreased to 35.23 ± 6.7,
and mean percentage excess weight loss was 41.19 ± 20.22 after RYGB within our follow-up period. RYGB as a revisional bariatric
procedure is effective to treat complications of restrictive procedures and to further reduce weight in morbidly obese patients. 相似文献
49.
Sandesh Parajuli Annamalai Arunachalam Kurtis J. Swanson Fahad Aziz Neetika Garg Robert R. Redfield Dixon Kaufman Arjang Djamali Jon Odorico Didier A. Mandelbrot 《Clinical transplantation》2019,33(12)
Simultaneous pancreas and kidney (SPK) and pancreas after kidney (PAK) transplant are both potential options for diabetic ESRD patients. Historically, PAK pancreas graft outcomes were felt to be inferior to SPK pancreas graft outcomes. Little is known about outcomes in the modern era of transplantation. We analyzed our SPK and PAK recipients transplanted between 01/2000 and 12/2016. There were a total of 635 pancreas and kidney transplant recipients during the study period, 611 SPK and 24 PAK. Twelve of the PAK patients received a living donor kidney. There were no significant differences between the two groups in kidney or pancreas graft rejection at 1 year. Similarly, 1‐year graft survival for both organs was not different. At last follow‐up, uncensored and death‐censored graft survival was not statistically different for kidney or pancreas grafts. In addition, in Cox regression analysis SPK and PAK were associated with similar graft survival. Although the majority of pancreas transplants are in the form of SPK, PAK is an acceptable alternative. Simultaneous pancreas and kidney avoids donor risks associated with live donation, so may be preferable in regions with short wait times, but PAK with a living donor kidney may be the best alternative in regions with long SPK wait times. 相似文献
50.
We present a case of solitary eosinophilic granuloma in the skull of a 6-year-old Saudi boy. This osteolytic lesion has fluid-fluid level on CT and MRI. We are presenting a rare radiological finding of eosinophilic granuloma. 相似文献