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951.
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Inflammatory aortic aneurysm (periaortic fibrosis): radiologic imaging   总被引:2,自引:0,他引:2  
Inflammatory aneurysms represent a distinct surgical entity with a reported incidence varying from 5% to 23% of all abdominal aortic aneurysms. Surgical repair of inflammatory aneurysms is associated with a higher morbidity and mortality than is repair of simple aortic aneurysms. Complicated cases require suprarenal aortic control, and the surgeon must be forewarned to maximize the chance for successful aneurysm repair. Preoperative diagnosis of this entity by cross-sectional imaging facilitates improved planning of the operative approach and permits the institution of preoperative steroid treatment to reduce the volume of the periaortic fibrotic mass. Ultrasound demonstrates the inflammatory process as a hypoechoic mass surrounding the intensely echogenic, thickened aortic wall. Computed tomography reveals a thickened, often calcified aortic wall and a mass of periaortic inflammatory tissue. Dynamic scanning reveals rapid intraluminal enhancement, slightly delayed enhancement of the inflammatory mass, and nonenhancement of the thick fibrous adventitia.  相似文献   
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Percutaneous cecostomy for decompression of the massively distended cecum   总被引:1,自引:0,他引:1  
Massive dilatation of the cecum developed in an elderly man following admission for an acute episode of upper gastrointestinal hemorrhage complicated by myocardial infarction, ventricular fibrillation, and pulmonary edema. A diagnosis of pseudo-obstruction was made. After an unsuccessful attempt at colonoscopy, percutaneous cecostomy was performed under computed tomographic guidance, using trocar technique. The cecal distention resolved and did not recur. Percutaneous cecostomy is an alternative to colonoscopy and to surgical cecostomy in the treatment of massive cecal distention.  相似文献   
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Computed tomography in white-matter disease   总被引:4,自引:0,他引:4  
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PURPOSE: To measure the biomechanical effect of the surgical capsulotomy made during a posterior cruciate ligament reconstruction using the tibial inlay technique. HYPOTHESIS: The posterior capsule contributes to posterior tibial stability. STUDY DESIGN: Controlled laboratory experiment. METHODS: Six knee specimens were tested on a robotic testing system from 0 degrees to 120 degrees of flexion with the posterior cruciate ligament intact and resected and with a posterior capsulotomy identical to that performed during tibial inlay reconstruction (sham surgery). A longitudinal incision with medial and lateral soft tissue stripping sufficient to mount an inlay bone block and pass an Achilles tendon graft into the knee was made in the oblique popliteal ligament, muscle belly of the popliteus, and posterior capsule. The posterior tibial translation was measured under a posterior tibial load of 130 N at multiple flexion angles. RESULTS: Capsulotomy increased the posterior laxity compared with the posterior cruciate ligament-resected knee at every flexion angle. An additional 0.97 +/- 0.48 mm, 0.65 +/- 0.47 mm, 0.56 +/- 0.33 mm, 0.48 +/- 0.38 mm, and 0.94 +/- 0.60 mm of posterior laxity was recorded at 0 degrees, 30 degrees, 60 degrees, 90 degrees, and 120 degrees of flexion, respectively. These values were all statistically significant (P < .001). CONCLUSIONS: A posterior capsulotomy alone, without associated posteromedial or posterolateral disruption, produces additional posterior tibial translation in vitro compared with posterior cruciate ligament-deficient knee with intact capsule. CLINICAL RELEVANCE: Damage to the posterior capsule may contribute to the residual posterior laxity noted clinically after posterior cruciate ligament reconstruction.  相似文献   
959.
OBJECTIVE: To compare the effects of isocaloric, energy-restricted very low-carbohydrate ketogenic (VLCK) and low-fat (LF) diets on weight loss, body composition, trunk fat mass, and resting energy expenditure (REE) in overweight/obese men and women. DESIGN: Randomized, balanced, two diet period clinical intervention study. Subjects were prescribed two energy-restricted (-500 kcal/day) diets: a VLCK diet with a goal to decrease carbohydrate levels below 10% of energy and induce ketosis and a LF diet with a goal similar to national recommendations (%carbohydrate:fat:protein = ~60:25:15%). SUBJECTS: 15 healthy, overweight/obese men (mean +/- s.e.m.: age 33.2 +/- 2.9 y, body mass 109.1 +/- 4.6 kg, body mass index 34.1 +/- 1.1 kg/m2) and 13 premenopausal women (age 34.0 +/- 2.4 y, body mass 76.3 +/- 3.6 kg, body mass index 29.6 +/- 1.1 kg/m2). MEASUREMENTS: Weight loss, body composition, trunk fat (by dual-energy X-ray absorptiometry), and resting energy expenditure (REE) were determined at baseline and after each diet intervention. Data were analyzed for between group differences considering the first diet phase only and within group differences considering the response to both diets within each person. RESULTS: Actual nutrient intakes from food records during the VLCK (%carbohydrate:fat:protein = ~9:63:28%) and the LF (~58:22:20%) were significantly different. Dietary energy was restricted, but was slightly higher during the VLCK (1855 kcal/day) compared to the LF (1562 kcal/day) diet for men. Both between and within group comparisons revealed a distinct advantage of a VLCK over a LF diet for weight loss, total fat loss, and trunk fat loss for men (despite significantly greater energy intake). The majority of women also responded more favorably to the VLCK diet, especially in terms of trunk fat loss. The greater reduction in trunk fat was not merely due to the greater total fat loss, because the ratio of trunk fat/total fat was also significantly reduced during the VLCK diet in men and women. Absolute REE (kcal/day) was decreased with both diets as expected, but REE expressed relative to body mass (kcal/kg), was better maintained on the VLCK diet for men only. Individual responses clearly show the majority of men and women experience greater weight and fat loss on a VLCK than a LF diet. CONCLUSION: This study shows a clear benefit of a VLCK over LF diet for short-term body weight and fat loss, especially in men. A preferential loss of fat in the trunk region with a VLCK diet is novel and potentially clinically significant but requires further validation. These data provide additional support for the concept of metabolic advantage with diets representing extremes in macronutrient distribution.  相似文献   
960.
Transient cerebellar mutism in the course of acute cerebellitis   总被引:2,自引:0,他引:2  
Transient mutism after posterior fossa surgery in children or associated with cerebellar hemorrhage or trauma is a recognized phenomenon. However, its association with parainflammatory cerebellitis has been rarely described. We report on a previously healthy 3-year-old child with severe cerebellitis after acute gastroenteritis of unidentified cause. Severe ataxia and transient mutism were the prevailing clinical features. Magnetic resonance imaging revealed swelling of the cerebellum with protruding cerebellar tonsils at the level of the occipital foramen. Recovery from the acute illness was slow and incomplete. Residual cerebellar dysfunction manifested with dysphonic and dysarthric speech, as well as motor coordination problems and was associated with atrophy of the vermis and cerebellar hemispheres in follow-up studies.  相似文献   
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