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排序方式: 共有975条查询结果,搜索用时 15 毫秒
971.
Crystal?M.?LuettersEmail author Jennifer?L.?Kelsey Theresa?H.?M.?Keegan Charles?P.?Quesenberry Stephen?Sidney 《Osteoporosis international》2003,14(11):918-922
Left-handedness has been associated with increased fracture risk in a small number of previous studies. This study reports risks for fractures at the proximal humerus, distal forearm, pelvis, foot, and shaft of the tibia/fibula according to handedness in a case-control study conducted from October 1996 to May 2001 among members of Northern California Kaiser Permanente. Handedness was assessed by questionnaire for 2,841 cases and 2,192 controls, and subjects were categorized as left-handed, right-handed, ambidextrous, or forced to switch from the left to the right hand. Compared to right-handedness, left-handedness was most strongly associated with an increased risk for proximal humerus fractures (adjusted odds ratio (OR)=2.00, 95% confidence interval (CI) 1.33 to 3.01) and less definitively with fractures of the distal forearm (adjusted OR=1.28, 95% CI 0.92 to 1.80), foot (adjusted OR=1.17, 95% CI 0.82 to 1.65), and pelvis (adjusted OR=1.40, 95% CI 0.71 to 2.74). Ambidextrous individuals had elevated risks for fractures of the distal forearm (adjusted OR=2.99, 95% CI 1.42 to 6.30), foot (adjusted OR=2.59, 95% CI 1.13 to 5.97), shaft of the tibia/fibula (adjusted OR=3.91, 95% CI 1.01 to 15.17), and proximal humerus (adjusted OR=2.37, 95% CI 0.85 to 6.65) when compared with right-handed individuals. Those individuals forced to use the right hand demonstrated no increased risk for fractures at any site. These results suggest that handedness does influence fracture risk, but the reasons for this increased risk are unclear. 相似文献
972.
Nicholas H Bunce Eliana Reyes Jennifer Keegan Catey Bunce Simon W Davies Christine H Lorenz Dudley J Pennell 《Journal of cardiovascular magnetic resonance》2004,6(2):527-539
The purpose of this study was to evaluate the feasibility and accuracy of combined coronary and perfusion cardiovascular magnetic resonance (CMR) in the assessment of coronary artery stenosis. Thirty-five consecutive patients (27 men, eight women, age range 34-81 years), undergoing cardiac catheterization, were assessed with 3D coronary CMR and rest-stress perfusion CMR. Significant coronary stenosis was determined by vessel narrowing or signal loss with coronary CMR, and by abnormal contrast enhancement with perfusion CMR. Coronary artery diameter stenosis greater than 50% was considered significant with conventional cardiac catheterization. Seventeen patients had significant coronary artery disease, and in these there were 35 significant stenoses on cardiac catheterization. All left main stem arteries were normal on both cardiac catheterization and coronary CMR. For the diagnosis of coronary artery stenosis, coronary CMR had a sensitivity of 92% for the left anterior descending artery (LAD), 79% for the right coronary artery (RCA), but only 13% for the circumflex coronary artery (LCX). Perfusion CMR had corresponding sensitivities of 69%, 86%, and 63%, respectively. For all arteries the accuracies for coronary and perfusion CMR were 67% and 72%, respectively. Combining coronary and perfusion CMR improved the accuracy to 77%. These data demonstrate that in patients with suspected coronary artery disease, combined coronary and perfusion CMR is feasible, increases the accuracy of detection of significant coronary stenosis, and offers the possibility of combined anatomical and hemodynamic assessment of coronary artery stenosis. 相似文献
973.
Transplantation of syngeneic Schwann cells to the retina of the rhodopsin knockout (rho(-/-)) mouse 总被引:4,自引:0,他引:4
Keegan DJ Kenna P Humphries MM Humphries P Flitcroft DI Coffey PJ Lund RD Lawrence JM 《Investigative ophthalmology & visual science》2003,44(8):3526-3532
PURPOSE: To determine whether subretinal Schwann cell transplantation can prolong the survival of photoreceptors in the rhodopsin knockout (rho(-/-)) mouse. METHODS: Schwann cells were prepared from postnatal day (PN) 5 to 7 mouse pups and grafted subretinally into the eyes of PN35 rho(-/-) mice. RT-PCR was performed on similarly prepared cells to determine growth factor production in vitro. Eyes were retrieved at PN70 for anatomic and statistical analysis. Control animals received grafts of fibroblasts or sham surgery. RESULTS: RT-PCR demonstrated the presence of message for ciliary neurotrophic factor (CNTF), brain-derived neurotrophic factor (BDNF), and glia-derived neurotrophic factor (GDNF) in the cultured Schwann cells. Schwann cell grafts produced a statistically significant rescue of photoreceptors in a restricted area of retina at PN70, but the effect was lost by PN140. Preserved inner segments could be identified, but outer segments were never present. Sham surgery also resulted in photoreceptor rescue but at a reduced level. Fibroblast grafts appeared to produce little or no rescue effect. Grafts of Schwann cells or fibroblasts and sham surgery induced a reactive Müller glial response. CONCLUSIONS: Schwann cells can prolong photoreceptor survival in the rhodopsin knockout mouse until at least PN70. 相似文献
974.
The epidermal growth factor receptor (EGFR) is a transmembrane protein with tyrosine kinase signaling activity regulating many essential cellular functions, and loss of function mutations in EGFR result in a life-threatening neonatal syndrome. We present the case of a preterm boy born with intrauterine growth restriction who developed multisystem disease due to a homozygous mutation in the EGFR gene. He experienced a tumultuous and complex clinical course with recurrent skin infections and sepsis, nephrocalcinosis, failure to thrive, severe electrolyte imbalances, rectal perforation, and thrombus formation, and died after 11 months due to renal failure. This case report builds on work recently published in 2020 describing a case series of 18 similar patients and adds to the growing literature describing the severe phenotype and multisystem disease associated with loss of EGFR mutation in the Roma population. 相似文献
975.
Richard T. Spence Keegan Guidolin Fayez A. Quereshy Sami A. Chadi David C. Chang Matthew M. Hutter 《Colorectal disease》2023,25(6):1248-1256