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991.
The very few reference epidemiological studies on myelodysplastic syndromes (MDS) have been carried out in Europe: Germany, France, UK and Sweden. We present the first Spanish study on the incidence and characteristics of MDS. The incidence rates, distribution by FAB subtypes, sex and age groups are within the ranges established by the reference studies with minimal differences which we point out and attempt to explain.  相似文献   
992.
993.
Acute normovolemic hemodilution: physiology, limitations, and clinical use   总被引:2,自引:0,他引:2  
Acute normovolemic hemodilution before major surgery is a relatively simple, cheap, and effective tool to avoid or reduce allogeneic blood transfusions. The anesthesiologist, however, must be familiar with the practical aspects of ANH. In addition, knowledge of the physiologic compensatory mechanisms that occur during ANH and their limits are mandatory for the safe use of this blood-saving technique.The decision whether or not to perform ANH and to what level and the concomitant use of other blood-saving techniques must be made on an individual basis, based on the locally present knowledge and training of the involved anesthesia personnel and tailored to the patient’s needs to suit and serve him best.  相似文献   
994.
Integrins are major extracellular matrix (ECM) receptors that can also serve for some cell-cell interactions. They have been identified as important regulators of mammary epithelial cell growth and differentiation. Their ability to promote cell anchorage, proliferation, survival, migration, and the induction of active ECM-degrading enzymes suggests that they play an essential role in normal mammary morphogenesis, but, on the other hand, reveals their potential to promote tumor progression.  相似文献   
995.
BACKGROUND: Hypertrophic pyloric stenosis is a relatively common disorder of the gastrointestinal tract in infancy, causing projectile vomiting and metabolic abnormalities. Surgical management in the form of pyloromyotomy under general anaesthesia has been reported as safe for relieving the obstructed bowel. A number of studies have demonstrated the advantages of spinal anaesthesia over general anaesthesia in high risk infants undergoing minor infraumbilical surgery. The purpose of this study was to evaluate spinal anaesthesia as an alternative option to general anaesthesia in infants undergoing pyloromyotomy. METHODS: Twenty-five infants undergoing pyloromyotomy under spinal anaesthesia were studied. Haemodynamic and respiratory parameters were noted before performing the spinal block, 5 min after the spinal block, and every 10 min after performing the spinal block; for a total period of 30 min. The spinal block was performed using spinal isobaric bupivacaine 0.5%, 0.8 mg.kg-1. Blood pressure, heart rate, respiratory rate and oxygen saturation values were recorded. RESULTS: The sensory levels achieved ranged between T3-T5 thoracic segments within 6-8 min and were sufficient to perform surgery in 23 cases. There were no statistically significant differences in the oxygen saturation, systolic blood pressure and respiratory rate compared with before the spinal block and after 5, 10, 20 and 30 min. CONCLUSIONS: This study proposes that spinal anaesthesia is an alternative option to general anaesthesia in infants undergoing pyloromyotomy, and should be considered in infants undergoing pyloromyotomy.  相似文献   
996.
997.
998.
An iatrogenic, longitudinal rupture of the membranous trachea, which extended from the thoracic inlet to 2.0 cm above the carina, was found intra-operatively, during the thoracic stage of a three-stage esophagectomy, in a female, 80-year-old patient. Tracheal rupture was the result of tracheal intubation with a 35-F double-lumen endotracheal tube. Tracheal rupture was successfully repaired by suturing a free pericardial patch at the edges of tracheal rupture, by application of BioGlue on the external patch surface and by covering tracheal repair with a pedicled serratus anterior muscle flap. The patient had a 25-day intensive care unit stay and video-bronchoscopy performed at the 25th postoperative day showed absence of granulation tissue formation and an acceptable tracheal lumen. The overall hospital stay was 83 days because of abdominal complications; no problems concerning the tracheal repair were observed during the prolonged postoperative period.  相似文献   
999.
Abstract. The aim of this paper is to provide the prevalence rates of mild, moderate and severe symptoms of social anxiety in a sample of high school students and to analyze gender differences and associated impairment levels within these three levels of severity. Five hundred and twenty students were assessed with the Social Anxiety Spectrum Self-Report (SHY-SR), a questionnaire that explores social anxiety spectrum. By applying two cut-off scores determined on a separate sample by using ROC analysis, the large majority (73.3 %) of subjects were classified as low scorers, 9% as medium scorers and 17.7% as high scorers. Fears related to social situations were reported both by high and medium scorers. Functional impairment defined by avoidance and school difficulties was more common among high scorers, but it was also reported to a significant extent by medium scorers. Compared to low and medium scorers, high scorers showed a higher F/M ratio (about 4:1) and a more homogeneous symptomatological profile in the two genders. In conclusion, our report confirms, in line with the literature, that even moderate levels of social anxiety are associated with significant functional impairment and distress for the individuals.  相似文献   
1000.
The distinct distribution of trkA receptors on small neurons and trkC receptors on large neurons in the dorsal root ganglion correlates with the dependence of these two classes of neurons on nerve growth factor and neurotrophin-3, respectively, for survival during development. In adult animals, the distribution of high affinity neurotrophin (trk) is complex and overlapping; neurotrophins are not required for cell survival, but may influence cell phenotype and the response to injury. In order to test the functional activity of trkA receptors in the sensory ganglia of adult animals in vivo, we examined the ability of a nerve growth factor-expressing recombinant replication-defective herpes simplex virus-based vector to prevent the selective degeneration of large sensory fibres caused by intoxication with pyridoxine. Transduction of dorsal root ganglion neurons in vivo by subcutaneous inoculation of the nerve growth factor-expressing vector prevented the development of pyridoxine-induced neuropathy measured by electrophysiological, morphological and behavioural measures. These results demonstrate a functional activity of trkA receptors expressed on large neurons in the dorsal root ganglion in mature animals; this observation has important implications for the choice of neurotrophic factors for treatment of peripheral nerve disease.  相似文献   
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