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91.
The differential diagnosis of a tibial intracortical diaphyseal lesion includes osteoid osteoma, periosteal chondroma, nonossifying fibroma, osteofibrous dysplasia, and adamantinoma. While osteoid osteomas represent 5% of all primary bone tumors, little is understood about intracortical chondromas. Intracortical chondroma was first described in 1990 and 7 reported cases have since been published. This article presents the first reported case of a pathologic fracture of an intracortical lesion in a child that shared radiographic and clinical features similar to those of osteoid osteoma, but on histopathologic examination revealed an intracortical chondroma. Our patient exhibited radiographic features of a poorly circumscribed cortical bone sclerosis, a centralized radiolucent nidus on computed tomography, and a hot bone scan of a lesion <1 cm in size that was consistent with an osteoid osteoma. An excision of the bone lesion was performed. The histopathology of the lesion revealed nodules of benign hyaline cartilage in cortical bone, consistent with an intracortical chondroma. Demarcated by cortical bone with mature Haversian systems rather than periosteum or cancellous bone, intracortical chondroma differs from the other 2 chondroma variants, periosteal chondroma and enchondroma, by its relationship to the surrounding bone. Enchondromas are characteristically understood to be asymptomatic. Intracortical chondromas along with periosteal chondromas have been found to present as painful lesions. The similarities with osteoid osteoma and intracortical chondroma in our patient make it circumspect in regards to ablating lesions (ie, needle radiofrequency ablation) without acquiring a biopsy in pediatric patients that both clinically and radiographically are presumably an osteoid osteoma.  相似文献   
92.
In this paper, we used repetitive transcranial magnetic stimulation (rTMS) in 18 normal subjects to investigate whether the ventral posterior parietal cortex (PPC) plays a causal role on visuospatial attention and primary consciousness and whether these 2 functions are linearly correlated with each other. Two distinct experimental conditions involved a similar visual stimuli recognition paradigm. In "Consciousness" experiment, number of consciously perceived visual stimuli was lower by about 10% after rTMS (300 ms, 20 Hz, motor threshold intensity) on left or right PPC than after sham (pseudo) rTMS. In "Attentional" Posner's experiment, these stimuli were always consciously perceived. Compared with sham condition, parietal rTMS slowed of about 25 ms reaction time to go stimuli, thus disclosing effects on endogenous covert spatial attention. No linear correlation was observed between the rTMS-induced impairment on attention and conscious perception. Results suggest that PPC plays a slight but significant causal role in both visuospatial attention and primary consciousness. Furthermore, these high-level cognitive functions, as modulated by parietal rTMS, do not seem to share either linear or simple relationships.  相似文献   
93.
Background Benign esophageal pseudoachalasia is a rare condition. Discussion We report the case of a 70-year-old man who complained of severe dysphagia after laparoscopic Nissen fundoplication and crural mesh repair performed for long-standing gastroesophageal reflux disease. Severe dysphagia and nocturnal aspiration developed soon after the operation. A marked dilatation of the esophageal body and a manometric pattern resembling achalasia was documented. Results Endoscopic balloon dilatation was ineffective. Five months after the initial operation, the patient underwent revisional laparoscopic surgery that consisted of Nissen’s wrap takedown, enlargement of the hiatus with partial resection of the mesh, Heller myotomy, and Dor fundoplication. After a 2-year follow-up, the patient is doing well and is free of symptoms.  相似文献   
94.
The blood-brain barrier is a natural diffusion barrier, which expresses active carriers extruding drugs on their way to the brain back into the blood against concentration gradients. Whereas these so-called adenosine triphosphate-binding cassette (ABC) transporters prevent the brain entry of toxic compounds under physiological conditions, they complicate pharmacotherapies in neurological disease. Recent observations in animal models of ischemic stroke, drug-resistant epilepsy, and brain cancer showed that the prototype of ABC transporters, ABCB1, is upregulated on brain injury, deactivation of this carrier considerably enhancing the accumulation of neuroprotective, antiepileptic, and chemotherapeutic compounds. These studies provide the proof of concept that the efficacy of brain-targeting drugs may significantly be improved when drug efflux is blocked. Under clinical conditions, efforts currently are made to enhance drug accumulation by selecting new compounds that do not bind to efflux carriers or deactivating ABC transporters by targeted downregulation or pharmacological inhibition. We predict that strategies aiming at circumventing drug efflux may greatly facilitate progress in neurological therapies.  相似文献   
95.

Objective

To compare the nutritional intake of patients with acute and chronic spinal cord injury (SCI).

Design

Cross-sectional, observational study.

Setting

Spinal cord unit.

Methods

Twelve in-house patients of a spinal cord unit with acute SCI and paralysis duration of 5.3 ± 2.5 months (acute group) were compared with 12 subjects with chronic SCI (chronic group) with lesion duration of 55.5 ± 21.0 months. All subjects recorded their nutritional intake for 7 days, which was analyzed for intake of energy, proteins, fat, carbohydrates, vitamins, mineral nutrients, fluid, and dietary fiber. Resting energy expenditure (REE) and total body fat were also determined.

Results

The chronic group showed a significantly higher total body fat content compared to the acute group (19.4 ± 3.8 vs. 15.7 ± 4.3%). All other parameters were not significantly different between groups. Both groups ingested excessive fat and insufficient amounts of carbohydrates compared with common nutritional recommendations. Low intakes of vitamins C, D, E, biotin, folic acid, as well as potassium and iron were found.

Conclusions

No differences were found in the nutritional intakes of two comparable groups of subjects with acute and chronic SCI. Independent of lesion duration, subjects with SCI showed considerable deviations from the general accepted nutritional recommendations concerning macro- and micronutrients intake. Professional nutritional education for persons with SCI should start as soon as possible after injury to prevent nutrition-related secondary complications like cardiovascular diseases. Periodic determinations of body fat content and REE combined with a physical activity program might be helpful as well.  相似文献   
96.
Pancreatic fistula: definition and current problems   总被引:1,自引:0,他引:1  
Postoperative pancreatic fistula (POPF) is the most common major complication after pancreatoduodenectomy (PD) and it can lead to prolonged hospital stay, increased costs, and mortality. The POPF rate is strictly correlated to the definition applied, but there are so many different definitions in the literature that comparison between published series of patients is difficult. The International Study Group of Pancreatic Fistula (IGSPF) has developed a new definition, with a grading system able to stratify complicated patients into three groups, based upon the clinical implications and costs of their postoperative course.The most important risk factors identified are a soft pancreatic texture and a main pancreatic duct diameter of 3 mm or less. Several surgical techniques have been studied in order to prevent anastomotic leakage, but none has been demonstrated to be superior to others. The use of somatostatin analogues is still matter of controversy. Conservative management of POPF is usually effective, but in patients with deteriorating clinical status with evidence of sepsis, surgical management is needed.  相似文献   
97.
98.
Spinal cord injury (SCI) leads to severe bone loss in the paralysed limbs and to a resulting increased fracture risk thereof. Since long bone fractures can lead to comorbidities and a reduction in quality of life, it is important to improve bone strength in people with chronic SCI. In this prospective longitudinal cohort study, we investigated whether functional electrical stimulation (FES) induced high-volume cycle training can partially reverse the loss of bone substance in the legs after chronic complete SCI. Eleven participants with motor-sensory complete SCI (mean age 41.9+/-7.5 years; 11.0+/-7.1 years post injury) were recruited. After an initial phase of 14+/-7 weeks of FES muscle conditioning, participants performed on average 3.7+/-0.6 FES-cycling sessions per week, of 58+/-5 min each, over 12 months at each individual's highest power output. Bone and muscle parameters were investigated in the legs by means of peripheral quantitative computed tomography before the muscle conditioning (t1), and after six (t2) and 12 months (t3) of high-volume FES-cycle training. After 12 months of FES-cycling, trabecular and total bone mineral density (BMD) as well as total cross-sectional area in the distal femoral epiphysis increased significantly by 14.4+/-21.1%, 7.0+/-10.8% and 1.2+/-1.5%, respectively. Bone parameters in the femoral shaft showed small but significant decreases, with a reduction of 0.4+/-0.4% in cortical BMD, 1.8+/-3.0% in bone mineral content, and 1.5+/-2.1% in cortical thickness. These decreases mainly occurred between t1 and t2. No significant changes were found in any of the measured bone parameters in the tibia. Muscle CSA at the thigh increased significantly by 35.5+/-18.3%, while fat CSA at the shank decreased by 16.7+/-12.3%. Our results indicate that high-volume FES-cycle training leads to site-specific skeletal changes in the paralysed limbs, with an increase in bone parameters at the actively loaded distal femur but not the passively loaded tibia. Thus, we conclude that high-volume FES-induced cycle training has clinical relevance as it can partially reverse bone loss and thus may reduce fracture risk at this fracture prone site.  相似文献   
99.
OBJECTIVE: To assess the reliability of 18-fluorodeoxyglucose positron emission tomography (18-FDG PET) in distinguishing benign from malignant cystic lesions of the pancreas. SUMMARY BACKGROUND DATA: The preoperative differential diagnosis of cystic lesions of the pancreas remains difficult: the most important point is to identify malignant or premalignant cysts that require resection. 18-FDG PET is a new imaging procedure based on the increased glucose metabolism by tumor cells and has been proposed for the diagnosis and staging of pancreatic cancer. METHODS: During a 4-year period, 56 patients with a suspected cystic tumor of the pancreas underwent 18-FDG PET in addition to computed tomography scanning, serum CA 19-9 assay, and in some instances magnetic resonance imaging or endoscopic retrograde cholangiopancreatography. The 18-FDG PET was analyzed visually and semiquantitatively using the standard uptake value. The accuracy of 18-FDG PET and computed tomography was determined for preoperative diagnosis of a malignant cyst. RESULTS: Seventeen patients had malignant tumors. Sixteen patients (94%) showed 18-FDG uptake with a standard uptake value of 2.6 to 12.0. Twelve patients (70%) were correctly identified as having malignancy by computed tomography, CA 19-9 assay, or both. Thirty-nine patients had benign tumors: only one mucinous cystadenoma showed increased 18-FDG uptake (standard uptake value 2.6). Five patients with benign cysts showed computed tomography findings of malignancy. Sensitivity, specificity, and positive and negative predictive values for 18-FDG PET and computed tomography scanning in detecting malignant tumors were 94%, 97%, 94%, and 97% and 65%, 87%, 69%, and 85%, respectively. CONCLUSIONS: 18-FDG PET is more accurate than computed tomography in identifying malignant pancreatic cystic lesions and should be used, in combination with computed tomography and tumor markers assay, in the preoperative evaluation of patients with pancreatic cystic lesions. A positive result on 18-FDG PET strongly suggests malignancy and, therefore, a need for resection; a negative result shows a benign tumor that may be treated with limited resection or, in selected high-risk patients, with biopsy, follow-up, or both.  相似文献   
100.
Background: Laparoscopic adjustable silicone gastric banding (LASGB) has replaced vertical banded gastroplasty (VBG) as the most widespread restrictive bariatric operation in Europe. Although these two procedures are similar in principle, the experience concerning the preoperative examinations and follow-up cannot be arbitrarily transferred from VBG to LASGB.The reasons for and consequences drawn from radiologic and endoscopic examinations are described. Methods: From December 1996 to January 2000, 148 patients (84% women, average age 39 years, body weight 127 kg, BMI 45 kg/m2) underwent LASGB. The mean follow-up was 17 months. Upper GI series, abdominal ultrasound, and gastroscopy were done before operation. The postoperative stoma adjustments were performed under radiological observation. All adjustments were analyzed. Results: Preoperative: Of 147 upper GI series, 74 showed hiatal hernia, 2 motility disorders, and 1 an incomplete malrotation. In 104 gastroscopies, 35 reflux and 53 gastritis with 24 Helicobacter pylori infections were found. Postoperative: On average, 2.7 radiological adjustments were done per patient. Until satisfactory satiety and weight reduction, 78% of the patients needed 0-3 adjustments. Besides routine adjustments, an additional 57 upper GI series were done in 35 patients, 44 times with opening of the stoma-diameter. A total of 14 slippages and 4 pouch enlargements were found. A gastroscopy was required in 12 patients. Conclusion: Radiologic and endoscopic examinations before LASGB revealed pathology needing therapy in 42% of the patients and provided important additional information influencing the operative procedure. At an average follow-up of 17 months, 24% of the 148 patients needed unplanned additional upper GI series.  相似文献   
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