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Background  

There are few effective strategies reported for the primary prevention of low back pain (LBP). Core stabilization exercises targeting the deep abdominal and trunk musculature and psychosocial education programs addressing patient beliefs and coping styles represent the current best evidence for secondary prevention of low back pain. However, these programs have not been widely tested to determine if they are effective at preventing the primary onset and/or severity of LBP. The purpose of this cluster randomized clinical trial is to determine if a combined core stabilization exercise and education program is effective in preventing the onset and/or severity of LBP. The effect of the combined program will be compared to three other standard programs.  相似文献   
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In situ saphenous vein grafts are being used with increasing frequency for bypass procedures involving the femoral and popliteal arteries. Complications of these procedures include anastomotic stenoses and persistent arteriovenous fistulae that may result in failure of the graft. Balloon angioplasty and embolotherapy with detachable balloons were employed successfully in three or four recent cases of patients with complications from in situ grafts. Tailored angiography is essential for evaluating in situ grafts, and interventional techniques are extremely useful for managing complications.  相似文献   
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The purpose of this study was to determine the effects of asimplified 80% Mono-Percoll sperm separation procedure on bothnormal and male factor semen samples compared with the standardswim-up technique. The parameters examined include sperm concentration,motility and morphology, total motile functional spermatozoaand percentage recovery. Normal patients demonstrated enhancedsperm parameters with the Mono-Percoll compared with the swim-uptechnique for concentration (67x106 versus 42x106/ml, P <0.001), motility (66 versus 59%, P < 0.001), morphology (56versus 49%, P < 0.005) and percentage recovery (60 versus42%, P < 0.005). Male factor patients showed enhanced spermparameters with the Mono-Percoll procedure compared with theswim-up technique for motility (53 versus 42%, P < 0.05)and percentage recovery (54 versus 29%, P < 0.005), withno significant difference in concentration and morphology. Insummary, the Mono-Percoll sperm recovery procedure is significantlybetter than the swim-up technique for male factor patients andpatients with normal sperm parameters.  相似文献   
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Intestinal schistosomiasis japonica: CT-pathologic correlation   总被引:1,自引:0,他引:1  
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The integrity of sperm DNA is crucial for the maintenance of genetic health. A major source of damage is reactive oxygen species (ROS) generation; therefore, antioxidants may afford protection to sperm DNA. The objectives of the study were, first, to measure the effects of antioxidant supplementation in vitro on endogenous DNA damage in spermatozoa using the single cell gel electrophoresis (comet) assay and, second, to assess the effect of antioxidant supplementation given prior to X-ray irradiation on induced DNA damage. Spermatozoa from 150 patients were prepared by Percoll centrifugation in the presence of ascorbic acid (300, 600 microM), alpha tocopherol (30, 60 microM), urate (200, 400 microM), or acetyl cysteine (5, 10 microM). DNA damage was induced by 30 Gy X-irradiation. DNA strand breakage was measured using the comet assay. Sperm DNA was protected from DNA damage by ascorbic acid (600 microM), alpha tocopherol (30 and 60 microM) and urate (400 microM). These antioxidants provided protection from subsequent DNA damage by X-ray irradiation. In contrast, acetyl cysteine or ascorbate and alpha tocopherol together induced further DNA damage. Supplementation in vitro with the antioxidants ascorbate, urate and alpha tocopherol separately has beneficial effects for sperm DNA integrity.   相似文献   
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