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Approximately 25% of all injury victims are in the pediatric age group, and one in four injured children will require a pediatric trauma center. According to the American College of Surgeons as well as many state guidelines, a level I pediatric trauma team should be directed by a pediatric surgeon. In 1986, the pediatric surgeon left our pediatric trauma center, but the center remained open under a cooperative effort by the adult trauma surgeons and pediatric intensivists. We have retrospectively reviewed the charts of all pediatric trauma patients (age less than or equal to 15 years) for the subsequent 4 years to determine the outcome of treatment without a pediatric surgeon. During this period, we treated 303 pediatric patients with multiple or serious single-system injuries. The mean age was 6.9 +/- 0.3 (SEM) years and 66% were boys. Falls were the cause of injury in 31% of the patients, with pedestrian/bicycle, motor vehicle crashes, and penetrating injuries resulting in 26%, 19%, and 3% of the injuries, respectively. The mean ISS was 15.6 +/- 0.8, and 73% of the patients had at least one AIS greater than or equal to 3. Surgical procedures were required in 48% of the patients. There were 27 deaths in this group, most commonly related to head injury (89%). The mean Pediatric Trauma Score of the patients who died was 1.6 +/- 0.8 and no patient with a Pediatric Trauma Score greater than 7 died.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Self-expanding endovascular graft: an experimental study in dogs   总被引:2,自引:0,他引:2  
An arterial endovascular graft was constructed by wrapping an expandable nylon mesh around a framework of Gianturco self-expanding metallic stents. The devices were passed through a 12-French Teflon catheter and positioned in the normal abdominal aorta of five dogs, two of which also had a device placed in an external iliac artery. At follow-up (1-6 months), all grafts remained patent, even though slight luminal narrowing due to neointimal encasement was noted. Histologically, all grafts were covered by neointimal proliferation at the time of removal. The graft material expanded with the stents, resulting in a tight fit between the graft and the vessel wall. Side branches narrowed but remained open because of the size of the nylon mesh. No migration of the grafts equipped with a barbed lead stent was noted. Expandable nylon mesh can be used as an endovascular graft material when wrapped around a framework of self-expanding stents. The resulting device can be easily delivered via transcatheter techniques, and once placed in a vessel, the nylon acts as a support for neointimal encasement, which forms a new vascular lumen.  相似文献   
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Summary The pharmacokinetics of diflunisal, a salicylate derivative that undergoes phenolic and acyl glucuronidation as well as sulphate conjugation, has been studied after a single oral dose (250 mg) in patients with cirrhosis (n=5) and in healthy controls (n=5).The plasma clearance of total (bound + unbound) diflunisal was 10.2 ml · min–1 in the control subjects and it was not affected by cirrhosis (10.9 ml · min–1). The plasma protein binding of diflunisal was significantly reduced in cirrhosis; the percentage of unbound diflunisal in plasma was 0.089 in the controls and 0.147 in the patients with cirrhosis. Plasma clearance of unbound diflunisal was significantly impaired in cirrhosis: 11.51 · min–1 in control subjects vs 7.41 · min–1 in cirrhotics.In cirrhotic patients, the unbound partial clearances to the phenolic and acyl glucuronides were both significantly reduced, by approximately 38%. The unbound partial clearance to the sulphate conjugate was not significantly affected by cirrhosis.The results show that both the phenolic and acyl glucuronidation pathways of diflunisal are equally susceptible to the effects of liver cirrhosis.  相似文献   
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Eleven mammalian toll-like receptors (TLRs 1–11) have been identified to date and are known to play a crucial role in the regulation of immune responses; however, the factors that regulate TLR expression and function in vivo are poorly understood. Therefore, in the present study, we investigated the physiological regulation of TLR expression and function in humans. To examine the influence of diurnal rhythmicity on TLR expression and function, peripheral venous blood samples were collected from healthy volunteers ( n = 8) at time points coinciding with the peak and nadir in the endogenous circulating cortisol concentration. While no diurnal rhythmicity in the expression of TLRs 1, 2, 4 or 9 was observed, the upregulation of costimulatory (CD80 and CD86) and antigen-presenting (MHC class II) molecules on CD14+ monocytes following activation with specific TLR ligands was greater ( P < 0.05) in samples obtained in the evening compared with the morning. To examine the influence of physical stress on TLR expression and function, peripheral venous blood samples were collected from healthy volunteers ( n = 11) at rest and following 1.5 h of strenuous exercise in the heat (34°C). Strenuous exercise resulted in a decrease ( P < 0.005) in the expression of TLRs 1, 2 and 4 on CD14+ monocytes. Furthermore, the upregulation of CD80, CD86, MHC class II and interleukin-6 by CD14+ monocytes following activation with specific TLR ligands was decreased ( P < 0.05) in samples obtained following exercise compared with at rest. These results demonstrate that TLR function is subject to modulation under physiological conditions in vivo and provide evidence for the role of immunomodulatory hormones in the regulation of TLR function.  相似文献   
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Atherosclerosis was induced in 20 Hanford miniature swine. Subsequently, one iliac artery lesion in each of 16 pigs was stented with either a self-expanding (8 pigs) or a balloon-expanded (8 pigs) stent. Immediately after stent placement, 4 animals in each group were taken off the atherogenic diet and continued on normal chow for the remainder of the study. Four months after stents were placed, atherosclerosis and the mural changes associated with the stent were more clearly evident in the arteries of the pigs continued on the atherogenic diet. These pigs also exhibited significantly more neointimal proliferation. In addition, the arteries containing the balloon-expanded stents showed more extensive and complex intimal changes when compared with arteries with self-expanding stents. Although both stent designs were equally effective in maintaining vascular patency, the balloon-expanded stent was more traumatic to the vessel wall which resulted in a significantly greater neointimal thickness.  相似文献   
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