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991.
Okolie Victoria O. Cisana Selena Schanfield Moses S. Akanmu Alani Sulaimon Adekoya Khalid O. Oyedeji Olufemi A. Podini Daniele 《International journal of legal medicine》2018,132(3):739-739
International Journal of Legal Medicine - In the original paper author Alani Sulaimon Akanmu was erroneously omitted from the author list. Prof. Akanmu has now been added as 4th author. Prof.... 相似文献
992.
993.
Masood Alqahtani Caitlin Edwards Natasha Buzzacott Karen Carpenter Khalid Alsaleh Abdulmalik Alsheikh Waleed Abozeed Miral Mashhour Afnan Almousa Yousef Housawi Shareefa Al Hawwaj Barry Iacopetta 《Familial cancer》2018,17(2):197-203
Individuals with Lynch syndrome (LS) have germline variants in DNA mismatch repair (MMR) genes that confer a greatly increased risk of colorectal cancer (CRC), often at a young age. Identification of these individuals has been shown to increase their survival through improved surveillance. We previously identified 33 high risk cases for LS in the Saudi population by screening for microsatellite instability (MSI) in the tumor DNA of 284 young CRC patients. The aim of the present study was to identify MMR gene variants in this cohort of patients. Peripheral blood DNA was obtained from 13 individuals who were at high risk of LS due to positive MSI status and young age (<60 years at diagnosis). Next generation sequencing, Sanger sequencing and Multiplex Ligation-dependent Probe Amplification were used to screen for germline variants in the MLH1, MSH2, MSH6 and PMS2 MMR genes. These were cross-referenced against several variant databases, including the International Society for Gastrointestinal Hereditary Tumors Incorporated database. Variants with pathogenic or likely pathogenic significance were identified in 8 of the 13 high risk cases (62%), comprising 4 in MLH1 and 4 in MSH2. All carriers had a positive family history for CRC or endometrial cancer. Next generation sequencing is an effective strategy for identifying young CRC patients who are at high risk of LS because of positive MSI status. We estimate that 7% of CRC patients aged <60 years in Saudi Arabia are due to LS, potentially involving around 50 new cases per year. 相似文献
994.
Ajay?MalhotraEmail authorView authors OrcID profile David?Durand Xiao?Wu Bertie?Geng Khalid?Abbed Diego?B.?Nunez Pina?Sanelli 《European radiology》2018,28(7):2823-2829
Purpose
To determine the utility of cervical spine MRI in blunt trauma evaluation for instability after a negative non-contrast cervical spine CT.Methods
A review of medical records identified all adult patients with blunt trauma who underwent CT cervical spine followed by MRI within 48 h over a 33-month period. Utility of subsequent MRI was assessed in terms of findings and impact on outcome.Results
A total of 1,271 patients with blunt cervical spine trauma underwent both cervical spine CT and MRI within 48 h; 1,080 patients were included in the study analysis. Sixty-six percent of patients with a CT cervical spine study had a negative study. Of these, the subsequent cervical spine MRI had positive findings in 20.9%; 92.6% had stable ligamentous or osseous injuries, 6.0% had unstable injuries and 1.3% had potentially unstable injuries. For unstable injury, the NPV for CT was 98.5%. In all 712 patients undergoing both CT and MRI, only 1.5% had unstable injuries, and only 0.42% had significant change in management.Conclusions
MRI for blunt trauma evaluation remains not infrequent at our institution. MRI may have utility only in certain patients with persistent abnormal neurological examination.Key Points
? MRI has limited utility after negative cervical CT in blunt trauma.? MRI is frequently positive for non-specific soft-tissue injury.? Unstable injury missed on CT is infrequent.995.
Fadi F Bitar Hala Bitar Marwan El Sabban Michael Nasser Khalid A Yunis Ayman Tawil Ghassan S Dbaibo 《Pediatric research》2002,51(2):144-149
To assess the effect of chronic hypoxia on cardiomyocyte apoptosis, we used an animal model that mimics cyanotic heart disease. Rats were placed in a hypoxic environment at birth, and oxygen levels were maintained at 10% in an air-tight Plexiglas chamber. Controls remained in room air. Animals were killed, and the hearts were harvested at 1 and 4 wk. Significant polycythemia developed in the hypoxic rats at 1 and 4 wk. Right ventricular mass in the hypoxic rats was 192% and 278% that of controls, and hypoxic left ventricular mass was 140% and 178% that of the controls at 1 and 4 wk, respectively. The increase in cardiac mass was paralleled by only mild hypertrophy (10 to 20%). Contrary to previous reports showing increased apoptosis in response to hypoxia in cultured cardiomyocytes, there was no difference in the number of apoptotic cardiomyocytes between the chronically hypoxic rats and controls, as assayed by terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling and Hoechst staining. We then examined the role of the sphingolipid ceramide because of its reported role in the stress response, growth suppression, and apoptosis. We found that the right ventricular ceramide content was significantly decreased in the hypoxic rats to 73% of control levels at the age of 4 wk. We suggest that the decrease in the ceramide content in the hypoxic right ventricular rat heart may be an adaptive response to chronic hypoxia and pulmonary hypertension. Lower ceramide levels may help suppress apoptosis and allow compensatory right ventricular cardiomyocyte proliferation. 相似文献
996.
997.
A cross-sectional study was carried out to determine the prevalence of diabetes mellitus and its relationship with age, physical activity, nutritional status and diet amongst rural Malays in Kuala Selangor. By simple random sampling 360 subjects were selected for the study. Besides guided questionnaires, subjects also underwent a 2 hours post prandial (2HPP) test to determine the diabetic status as recommended by WHO. The crude prevalence of diabetes mellitus was 14.6% which increases with age. The prevalence of diabetes adjusted for age was 12.2%. Physical activity status seemed to be a significant risk factor for diabetes. A greater proportion of diabetics was obese and their mean fat intake was higher than normal subjects (p < 0.05). The prevalence of diabetes mellitus in this study was significantly higher compared with data from 1984 (3.9%), representing a marked increment of 212.8 per cent over a 10-year period. 相似文献
998.
Ahmed M. Abu El-Asrar Abdul-Kareem Al-Momen Saleh Al-Amro Abdel Galil M. Abdel Gader Khalid F. Tabbara 《International ophthalmology》1996,20(4):197-204
Background. The etiology of retinal venous occlusion in young patients is not well understood although thrombosis does occur histologically. A search for the risk factors that may lead to thrombosis is highly desirable may contribute to our understanding of the pathogenesis of this complication and may improve our therapeutic strategies. Methods. We studied 17 patients with retinal venous occlusion. All patients were under 45 years of age (mean 37.8 ± 7.1). Antiphospholipid antibodies (APAs) and certain hemostatic factors were determined. The results obtained in these patients were compared to those of normal controls. Results. We found APAs in 8 out of 17 patients compared to 5 out of 60 controls (p = 0.0002). In patients with major trunk occlusion, there was a trend for the presence of APAs in those with poor visual acuity at presentation. Deficiencies of the coagulation inhibitor proteins C and S and antithrombin III activities were detected in 6 patients, and reduced levels of Factor XII were found in 4 patients. Levels of hematocrit, erythrocyte sedimentation rate, Fibrinogen, 1-globulin, and 2-globulin were significantly higher in patients compared to the controls (p = 0.019; 0.014; 0.0001; 0.011; 0.047), indicating increased blood viscosity in patients with retinal venous occlusion. Conclusion: Prothrombotic changes in the form of APAs and/or deficiencies of coagulation inhibitors and Factor XII may contribute to the etiology of retinal venous occlusion in young adults. Young patients with retinal venous occlusion should be evaluated for these prothrombotic states. 相似文献
999.
Khalid?AlsalehEmail author Derek?Ho M.?Patricia?Rosas-Arellano Tanya?Charyk?Stewart Kevin?Roger?Gurr Christopher?Stewart?Bailey 《European spine journal》2017,26(2):362-367
Objective
To determine the reliability and dependability of magnetic resonance imaging (MRI) and computerized tomography (CT) in the assessment of lumbar spinal stenosis and correlate the qualitative assessment to both a quantitative assessment and functional outcome measures.Summary of background data
Multiple studies have addressed the issue of CT and MRI imaging in lumbar spinal stenosis. None showed superiority of one modality.Methods
We performed a standardized qualitative and quantitative review of CT and MRI scans of 54 patients. Intra-observer and inter-observer reliability was determined between three reviewer using Kappa coefficient. Agreement between the two modalities was analyzed. ODI and SF-36 outcomes were correlated with the imaging assessments.Results
Almost perfect intra-observer reliability for MRI was achieved by the two expert reviewers (κ = 0.91 for surgeon and κ = 0.92 for neuro-radiologist). For CT, substantial intra-observer agreement was found for the surgeon (κ = 0.77) while the neuro-radiologist was higher (κ = 0.96). For both CT and MRI the standardized qualitative assessment used by the two expert reviewers had a better inter-observer reliability than that between the expert reviewers and the general reporting radiologist, who did not utilize a standardized assessment system. When the qualitative assessment was compared directly, CT overestimated the degree of stenosis 20–35 % of the time (p < 0.05) while MRI overestimated the degree of stenosis 2–11 % of the time (p < 0.05). No correlation was found between qualitative and quantitative analysis with functional status.Conclusions
This study directly demonstrates that MRI is a more reliable tool than CT, but neither correlates with functional status. Both experience of the reader and the standardization of a qualitative assessment are influential to the reliability.1000.
Matthew J. Lee Khalid M.S. Mohamed John C. Kelly John G. Galbraith John Street Brian J. Lenehan 《The Journal of arthroplasty》2017,32(9):2648-2654