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To present the findings in a 10-year-old male with a Chance fracture and associated aortic vascular injury and review of the literature on the subject. We reviewed the clinical and imaging findings in a patient who was in a serious motor vehicle accident, sustaining a Chance fracture of the lumbar spine and associated aortic and common iliac vessel injury. We also accomplished a literature review. Evidence of an associated aortic injury was available on the initial computed tomography (CT) study, but the findings were more exquisitely demonstrated on reconstructed studies of the lumbar spine. Our literature review indicated that aortic injury associated with Chance fracture is relatively rare and often overlooked. Abdominal aortic injury although rare, can occur with Chance fractures. With the now present sophisticated CT imaging in most Emergency Rooms it is possible to obtain exquisite reconstructed images of all organ systems including the vascular tree. The images may provide enough details so that further delineation of any given problem may not be necessary.  相似文献   
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Core decompression procedures have been used in osteonecrosis of the femoral head to attempt to delay the joint destruction that may necessitate hip arthroplasty. The efficacy of core decompressions has been variable with many variations of technique described. To determine whether the efficacy of this procedure has improved during the last 15 years using modern techniques, we compared recently reported radiographic and clinical success rates to results of surgeries performed before 1992. Additionally, we evaluated the outcomes of our cohort of 52 patients (79 hips) who were treated with multiple small-diameter drillings. There was a decrease in the proportion of patients undergoing additional surgeries and an increase in radiographic success when comparing pre-1992 results to patients treated in the last 15 years. However, there were fewer Stage III hips in the more recent reports, suggesting that patient selection was an important reason for this improvement. The results of the small-diameter drilling cohort were similar to other recent reports. Patients who had small lesions and were Ficat Stage I had the best results with 79% showing no radiographic progression. Our study confirms core decompression is a safe and effective procedure for treating early stage femoral head osteonecrosis.  相似文献   
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Sheth K  Friel J  Nolan B  Bankey P 《Surgery》2001,130(2):242-248
BACKGROUND: Prolonged polymorphonuclear neutrophil (PMN) survival has been implicated in tissue injury after sepsis. Previously we reported that lipopolysaccharide (LPS) inhibits PMN apoptosis via the activation of the extracellular signal-regulated kinase (ERK). Conversely, the p38 mitogen activated protein kinase (MAPK) pathway is involved in the spontaneous apoptosis of PMNs. The interaction between these 2 pathways and their ability to regulate apoptosis during sepsis remain largely undefined. We hypothesize that there is interaction between the ERK and p38 pathways during sepsis. METHODS: PMNs were isolated from healthy volunteers by Ficoll gradient centrifugation and red blood cell sedimentation. Cells were then pretreated for 1 hour with the ERK inhibitor (PD98059, 10 micromol/L), p38 inhibitor (SB203580, 1 micromol/L), or vehicle. After treatment with LPS, apoptosis and MAPK activity were correlated. RESULTS: LPS stimulation significantly inhibits PMN apoptosis compared with unstimulated cells. Furthermore, inhibition of ERK significantly abrogates this effect, whereas inhibition of p38 augments LPS induced inhibition of apoptosis. Elk-1 phosphorylation (ERK target) is significantly increased by LPS alone and by inhibition of the p38 pathway during LPS stimulation. This correlates with ERK phosphorylation by Western blot. CONCLUSIONS: These data show that p38 inhibition enhances ERK activity during endotoxemia. Furthermore, these data suggest that cooperation between ERK and p38 MAPK pathways dictates the apoptotic potential of PMNs during inflammatory states.  相似文献   
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Hypothalamic-hypophyseal-testicular abnormalities and erectile dysfunction   总被引:1,自引:0,他引:1  
Forty-five men presenting with erectile dysfunction were evaluated through history and nocturnal penile tumescence, Doppler, and EMG studies. Fifteen were classified as having organic and 30 as having psychogenic impotence. Three men had mild hypergonadotropism with low testosterone levels. One had hyperprolactinemia. No case of hypogonadotropic hypogonadism was detected. Six patients who had psychogenic impotence had low levels of testosterone.  相似文献   
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Prolactin-regulating factor (PRF) of molecular size of 25 kD has been isolated from human seminal plasma. This 25 kD factor inhibits circulating PRL levels in intact adult male rats to the extent of about 48% at dose level of 10 micrograms. Furthermore, in vitro incubation of pituitary demonstrated that PRF inhibits the release of PRL in the medium. PRF also interferes with the binding of I125 PRL to its receptors in liver, prostate, and spermatozoa. However, I125 PRF itself does not bind to these receptors. PRF seems to modulate PRL release as well as its binding to receptors. A sensitive, specific RIA was developed for PRF. Using the RIA, levels of PRF in seminal plasma were measured. PRF levels were low in vasectomized subjects as compared with controls. A negative correlation was noted with seminal plasma PRF levels and sperm count.  相似文献   
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