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11.
Except for two reported patients, increased free sialic acid excretion has been associated with lysosomal storage. This is a report of a child with progressive neurologic deterioration and increased excretion of free sialic acid. Although lysosomal storage was absent, nuclear invagination or inclusions were present.  相似文献   
12.
Pediatric orbital pseudotumor may be associated with iritis, unlike the adult form of this disorder. However, orbital pseudotumor is seldom considered in the differential diagnosis of childhood uveitis. We report two cases of children with uveitis who were ultimately diagnosed as having orbital pseudotumor. No proptosis was noted in either child. For those pediatric patients with a persistent or recurrent uveitis and a previous negative diagnostic workup, the possibility of an orbital pseudotumor should be considered and ultrasonography, magnetic resonance imaging, and/or computed tomography performed.  相似文献   
13.
We have previously described the development of new hepatic surgical techniques using the ultrasonic surgical dissector. With 10 years' experience, we have found that major liver resections have been simplified and that the technique is repeatable in hands other than our own. Thirty-three patients had 37 tumors, averaging 5.65 cm in size, resected with an average blood loss of only 1,020 mL per case, which included 5 right trisegmentectomies, 12 lobectomies, 15 segmental resections, and 4 subsegmental resections. Twenty-two patients had metastatic colorectal cancer. Blood transfusion requirements averaged only 2.24 units in long-term survivors, which was significantly less than the 3.5 units received by patients who have since died (p = 0.092). There were no operative deaths. The median survival of these 22 patients was 56 months, and the 5-year actuarial survival rate was 35%. All of the early deaths occurred in patients with more than four tumors, and no patient with less than four tumors died before 42 months with recurrent disease. Six patients had bilateral tumors, and the fact that patients survived into the fourth and fifth post-resectional year indicates that resection was worthwhile. All these patients had Dukes' C primary tumors, but we found no statistical difference in survival between patients with Dukes' B and Dukes' C lesions. The results indicate that hepatic resection with the ultrasonic surgical dissector decreases blood loss, requires few transfusions, is safe to perform, and is associated with excellent long-term survival.  相似文献   
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The present paper outlines the development and evaluation of an allocation committee to distribute community placements on an equitable basis between universities. Although based on our experience in South Australia with the University Placement Allocation Committee (UPAC), the primary goal is to outline the steps that would be useful if placement coordinators at other universities in Australia decided to establish and maintain an allocation committee. A survey of field supervisors was also conducted and field supervisors endorsed UPAC as a constructive mechanism for allocating community placements.  相似文献   
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Experimental columnar metaplasia in the canine oesophagus   总被引:7,自引:0,他引:7  
Regeneration of canine oesophageal mucosa was studied under basal conditions and in the presence of gastro-oesophageal reflux. In normal circumstances mucosal defects in the oesophagus regenerate by squamous epithelium. In the presence of gastro-oesophageal reflux of either acid or a combination of acid and bile, regeneration was frequently by columnar epithelium (Barrett's oesophagus). This columnar regeneration was not seen with bile reflux alone. By the use of squamous barriers to proximal migration of columnar epithelium in the stomach, it was demonstrated that columnar re-epithelialization may occur from cells intrinsic to the oesophagus and is not dependent on proximal migration of cardiac columnar epithelium. The cell of origin of this epithelium may be located in oesophageal gland ducts and is likely to be a multipotential stem cell since the regenerated columnar epithelium may contain goblet and parietal cells not normally found in the oesophagus. This epithelium is morphologically distinct on mucin histochemistry from cardiac columnar epithelium. These findings support the concept that Barrett's epithelium is metaplastic.  相似文献   
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Current knowledge of alveolar pathophysiology during early sepsis-induced acute lung injury (ALI) and the role of resident alveolar macrophages (AM) in mediating alveolar inflammatory events during sepsis is limited. Further, the effects of ibuprofen pretreatment upon alveolar pathophysiology and AM function during early sepsis-induced ALI is unclear. Utilizing repetitive bronchoalveolar lavage (BAL) in a porcine model of sepsis-induced ALI, we studied changes in alveolar cellular constituents, BAL protein content and molecular composition, and AM superoxide anion (O2-.) generation during early sepsis. The neutrophil percentage of recovered alveolar cells (17 +/- 8%, t = 300 min versus 2 +/- 1%, t = 0; p = 0.06) and the bronchoalveolar lavage total protein content (493 +/- 110 micrograms/ml, t = 300 min versus 109 +/- 18 micrograms/ml, t = 0; p less than 0.05) increased in septic animals. Increases in BAL fluid total protein were primarily due to low-molecular-weight plasma protein, indicating relative preservation of alveolar-capillary membrane size selectivity. Alveolar macrophages harvested following 300 min of sepsis generated significantly less O2-. following phorbol myristate acetate (PMA) stimulation compared to AM harvested at baseline. Ibuprofen pretreatment of septic animals completely blocked leakage of plasma proteins into the alveoli and attenuated neutrophil migration but did not prevent downregulation of AM O2-. generation. Increased alveolar-capillary membrane permeability, neutrophil migration into the alveoli, and downregulation of AM oxidant generation occur within hours of the onset of sepsis. Ibuprofen pretreatment significantly attenuates early sepsis-induced ALI without altering sepsis-induced AM dysfunction.  相似文献   
19.
In spite of significant advances in the knowledge and understanding of the multi-factorial nature of obesity, many questions regarding the specific consequences of the disease remain unanswered. In particular, there is a relative dearth of information pertaining to the functional limitations imposed by overweight and obesity. The limited number of studies to date have mainly focused on the effect of obesity on the temporospatial characteristics of walking, plantar foot pressures, muscular strength and, to a lesser extent, postural balance. Collectively, these studies have implied that the functional limitations imposed by the additional loading of the locomotor system in obesity result in aberrant mechanics and the potential for musculoskeletal injury. Despite the greater prevalence of musculoskeletal disorders in the obese, there has been surprisingly little empirical investigation pertaining to the biomechanics of activities of daily living or into the mechanical and neuromuscular factors that may predispose the obese to injury. A better appreciation of the implications of increased levels of body adiposity on the movement capabilities of the obese would afford a greater opportunity to provide meaningful support in preventing, treating and managing the condition and its sequelae. Moreover, there is an urgent need to establish the physical consequences of continued repetitive loading of major structures of the body, particularly of the lower limbs in the obese, during the diverse range of activities of daily living.  相似文献   
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