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21.
A case report of an intracranial chondroma is discussed with emphasis on magnetic resonance imaging.  相似文献   
22.
Aviation medicine came into existence as a recognized entity when certain standards were established during and shortly after World War I. During this time, accident rates were high. In fact, a larger number of pilots were dying in accidents than in combat. Figures from Great Britain's casualty list at the close of the first year of World War I indicated that for every 100 aviators killed, 60 died as a result of some individual physical defect, 30 from some form of recklessness or careless behavior, 8 as a result of some mechanical defect in the airplane, and only 2 at the hands of the enemy. Aviators were found to be in poor physical condition. Because there were no established regulations with regard to workloads, aviators were frequently found to have been flying to a point beyond exhaustion. Because of workload, chronic fatigue, and emotional stress, aviators were constantly called upon to perform superhuman feats when not in peak physical condition. Errors in judgement were common. The majority of pilots lost weight as a somatic sign of stress. This was recognized by Theodore Lyster [corrected] who had recently been appointed as the Chief Surgeon, Aviation Section of the U.S. Army. Such problems were not diagnosed by medical officers because they were not trained to recognize them. Theodore Charles Lyster [corrected] was the son of Captain William J. and Martha Doughty Lyster [corrected]. He was an Army "brat" who entered the world on July 10, 1875. His childhood was spent in various posts around the country. At the age of 7, Lyster [corrected] contracted yellow fever while living in Fort Brown, TX. The boy was treated by William Gorgas, a young post surgeon. Gorgas was credited with the young boy's recovery. Later, Gorgas was to marry Lyster's [corrected] aunt making Lyster [corrected] his nephew by marriage. Having survived the yellow fever infection, young Lyster [corrected] had a lifelong immunity to the disease.  相似文献   
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The hypothesis that extracellular truncation of the common receptor subunit for interleukin-3 (IL-3), granulocyte-macrophage colony- stimulating factor, and IL-5 (h beta c) can lead to ligand-independent activation was tested by infecting factor-dependent hematopoietic cell lines with retroviruses encoding truncated forms of h beta c. A truncation, resembling that in v-Mpl, and retaining 45 h beta c-derived extracellular residues, led to constitutive activation in the murine myeloid cell line, FDC-P1. However, infection of cells with retrovirus encoding a more severely truncated receptor, retaining only 7 h beta c- derived extracellular residues, did not confer factor independence on these cells. These experiments show that truncation activates the receptor and define a 37-amino acid segment of h beta c (H395-A431) which contains two motifs conserved throughout the cytokine receptor superfamily (consensus Y/H XX R/Q VR and WSXWS), as essential for factor-independent signaling. The mechanism of activation was also investigated in less severe truncations. A receptor that retains the entire membrane-proximal domain (domain 4) also conferred factor independent growth on FDC-P1 cells; however, a retrovirus encoding a truncated form of h beta c having two intact membrane proximal domains did not have this ability, suggesting that domain 3 may have an inhibitory role in h beta c. The ability of these receptors to confer factor independence was cell specific as demonstrated by their inability to confer factor-independent growth when introduced into the murine IL-3-dependent pro-B cell line BaF-B03. These results are consistent with a model in which activation requires unmasking of an interactive receptor surface in domain 4 and association with a myeloid- specific receptor or accessory component. We suggest that in the absence of ligand intramolecular interactions prevent inappropriate signaling.  相似文献   
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The aetiology of idiopathic scoliosis (IS) remains unknown; however, there is a growing body of evidence suggesting that the spine deformity could be the expression of a subclinical nervous system disorder. A defective sensory input or an anomalous sensorimotor integration may lead to an abnormal postural tone and therefore the development of a spine deformity. Inhibition of the motor cortico-cortical excitability is abnormal in dystonia. Therefore, the study of cortico-cortical inhibition may shed some insight into the dystonia hypothesis regarding the pathophysiology of IS. Paired pulse transcranial magnetic stimulation was used to study cortico-cortical inhibition and facilitation in nine adolescents with IS, five teenagers with congenital scoliosis (CS) and eight healthy age-matched controls. The effect of a previous conditioning stimulus (80% intensity of resting motor threshold) on the amplitude of the motor-evoked potential induced by the test stimulus (120% of resting motor threshold) was examined at various interstimulus intervals (ISIs) in both abductor pollicis brevis muscles. The results of healthy adolescents and those with CS showed a marked inhibitory effect of the conditioning stimulus on the response to the test stimulus at interstimulus intervals shorter than 6 ms. These findings do not differ from those reported for normal adults. However, children with IS revealed an abnormally reduced cortico-cortical inhibition at the short ISIs. Cortico-cortical inhibition was practically normal on the side of the scoliotic convexity while it was significantly reduced on the side of the scoliotic concavity. In conclusion, these findings support the hypothesis that a dystonic dysfunction underlies in IS. Asymmetrical cortical hyperexcitability may play an important role in the pathogenesis of IS and represents an objective neurophysiological finding that could be used clinically.  相似文献   
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Accidental ingestion of foreign bodies is a common problem in children, but ingestion of magnets is rare. When multiple magnets are ingested, they may attract each other through the intestinal walls, causing pressure necrosis, perforation, fistula formation, or intestinal obstruction; as has been reported in 13 cases in the past 10 years. We report the fifth case in the literature of intestinal perforation and fistula caused by the ingestion of 2 small magnetic pieces of a toy by a 3-year-old boy. We find it necessary that sanitary authorities give more information to parents and physicians about the potential risks of these magnetic toys.  相似文献   
29.

Introduction

Despite the excellent results obtained with standard laparoscopic cholecystectomy, the efforts for minimizing the ports needed to reduce postoperative pain, for a quicker recovery and to improve the patient's cosmetics continue. The aim of this study is to report the results of the first 100 cases of single port laparoscopic cholecystectomy performed in a secondary care hospital.

Material and methods

Prospective, observational and unicentric study including 100 patients between January 2010 and April 2012. Inclusion criteria: symptomatic cholelythiasis patients over 16-years of age on whom a single port laparoscopic cholecystectomy was performed. Exclusion criteria: history of acute cholecystitis, pancreatitis or suspected choledocholithiasis, Endoscopic retrograde cholangiopancreatography, BMI > 35 and previous laparotomies. We studied epidemiological, surgical and safety variables.

Results

The mean patient age was 39,89 ± 11,5 years. The mean time of the surgical procedure was 67,94 ± 25,5 min. There were 2 cases of postoperative complications. A non-infected seroma and a biliar leak. In 2 cases the use of an accessory trocar was needed. The mean hospital stay was 1,13 ± 0,8 days. A total of 35% patients were included in the major ambulatory surgery programme.The overall patient satisfaction survey rating showed a high level of cosmetic satisfaction in 100% of patients.

Conclusions

Single port laparoscopic cholecystectomy is a good technique when performed in selected cases by expert surgeons. It is feasible to include the single port laparoscopic cholecystectomy in a major ambulatory surgery programme. We have not had serious complications. There is a high cosmetic satisfaction index with this technique.  相似文献   
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