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991.
Lesions of the spinal accessory nerve are usually iatrogenic, especially after lymph node extirpation on the neck. Between 1994 and 2003, 31 patients were operated on in the Neurosurgical Department of the University of Ulm for iatrogenic lesions of the XIth cranial nerve. Of 31 patients, 22 had undergone a previous lymph node extirpation, 2 had been injured during a selective peripheral denervation for spasmodic torticollis, and the other 7 patients by different causes. The neurosurgical intervention was performed 0-19 months after trauma (mean 7.2 months). All patients showed paresis/atrophy of the trapezius muscle, and the abduction of the shoulder was markedly reduced. Additional neck and/or shoulder pain was present in 29 of 31 cases. In seven cases, the nerve was compressed by scar tissue and subsequently treated by external neurolysis. Ten patients underwent an end-to-end anastomosis; autologous sural nerve grafting was necessary in 13 cases. After a mean follow-up of 12.6 months, 7of 31 patients completely recovered. Of 31 patients, 19 experienced partial relief of pain and weakness. Only five patients remained unchanged. The clinical findings after autologous nerve grafting, end-to-end reconstruction, or external neurolysis did not show any significant differences. Microsurgical reconstruction of iatrogenic injury of the spinal accessory nerve is very promising if the interval between trauma and surgical revision is less than 6 months. Up to 12 months, partial recovery can be achieved. Outcome after longer delay is unsatisfactory.  相似文献   
992.
Galanin (GAL) impairs performance on cognitive tasks when administered centrally to rats. GAL transgenic (GAL-tg) mice overexpressing endogenous GAL show deficits on the probe trial of the Morris water maze spatial learning task, on the social transmission of food preference olfactory memory task, and on the trace cued fear conditioning emotional learning and memory task. Knockout mice deficient in the GAL-R1 receptor subtype were normal on most memory tasks, while showing a small deficit in trace cued fear conditioning, suggesting a selective role for the GAL-R1 in aversive memories, and implicating other GAL receptor subtypes in spatial learning and olfactory social memory. The growing body of rodent literature implicating excess GAL in cognitive impairment is relevant to the overexpression of GAL in the basal forebrain during the progression of Alzheimer's disease.  相似文献   
993.
BACKGROUND: Previous studies have shown that 20% of all patients admitted to the hospital abuse alcohol and have increased morbidity after surgery. Long-term alcoholic patients are shown to suffer from immune alterations, which might be critical for adequate postoperative performance. Cardiac surgery with cardiopulmonary bypass (CPB) also leads to pronounced immune alteration, which might be linked with patients' ability to combat infections. Therefore, the aim of our study was to investigate the perioperative levels of TNF-alpha, interleukin-6, interleukin-10, and cortisol in long-term alcoholic and nonalcoholic patients undergoing cardiac surgery to elucidate a possible association with postoperative infections. METHODS: Forty-four patients undergoing elective cardiac surgery were included in this prospective study. Long-term alcoholic patients (n=10) were defined as having a daily ethanol consumption of at least 60 g and fulfilling the Diagnostic and Statistical Manual of Mental Disorders for alcohol abuse. The nonalcoholic patients (n=34) were defined as drinking less than 20 g ethanol per day. Blood samples were obtained to analyze the immune status upon admission to hospital, the morning before surgery and on admission to the ICU, the morning of days one and three after surgery. RESULTS: Basic characteristics of patients did not differ between groups. Long-term alcoholics had a fourfold increase in postsurgery infection rate and prolonged need for ICU treatment and mechanical ventilation. Postoperative levels of interleukin-10 and cortisol were significantly increased in long-term alcoholic patients compared with nonalcoholic patients. These observations were in line with postoperative interleukin-10 being predictive for postoperative infectious complications. CONCLUSIONS: The increased infection rate in long-term alcoholics strengthens the urgent need for interventional approaches providing modulation of the perioperative immune and HPA response in these high-risk patients to counteract their postoperative immune suppression.  相似文献   
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BACKGROUND AND AIM: According to the report of the Intercollegiate Standing Committee on Nuclear Medicine, the UK requires 40-60 positron emission tomography (PET) machines in the next decade (Intercollegiate Standing Committee on Nuclear Medicine). Positron Emission Tomography: a Strategy for Provision in the UK. London: Royal College of Physicians of London; 2003, pp. 1-9). This figure is based mainly on patients receiving only one examination and restricting the clinical indication to three primary diagnoses. The aim of this study was to assess the appropriateness of this figure and the assumptions made in the Intercollegiate report on UK PET provision. METHODS: We examined retrospectively our institution's entire PET and PET/computed tomography (CT) database, which spans 4 years and 9 months. We recorded the number of patients who received repeat examinations. RESULTS: Reports were available for 3354 PET/CT or PET-only studies; 418 of 2268 patients (18.4%) received at least one repeat PET/CT examination. The three main indications for PET examination in the Intercollegiate report only accounted for approximately 60% of the examinations undertaken. CONCLUSION: Our records suggest that basing the UK's future PET provision on a single examination and on three clinical indications only is no longer realistic.  相似文献   
998.
OBJECTIVE: Our objective was to assess the potential use of MDCT in the detection of occult scaphoid fractures. Fifty-one patients with suspected radiographically occult scaphoid fractures at 10-14 days after trauma were investigated prospectively with skeletal scintigraphy and CT on the same day. Planar images of the wrist were taken 3 hr after IV injection of 400 MBq of (99m)Tc-methylene diphosphonate using a single-head gamma camera. CT was performed on a 16-MDCT machine using 0.75-mm detectors and reconstruction in 0.5-mm slices. Multiplanar reformatted images were then viewed in interactive cine mode. The examinations were reported independently, and discordant results were compared at follow-up. CT was positive for wrist fracture in 14 (27.4%) of 51 patients and skeletal scintigraphy in 23 (45.1%) of 51 patients. Even after retrospective review, there were seven discrepant cases (13.7%), all of which were positive for wrist fracture on scintigraphy but negative on CT. Four of these seven patients with discordant findings underwent further radiography at 6 weeks, which did not show fracture. CONCLUSION: Although CT was preferred by most patients and was quicker, scintigraphy appears to detect bony abnormality more frequently. However, there appears to be an interesting group of patients (7/51) with normal initial radiography findings but positive scintigraphy findings who would normally be considered to have a fracture but for whom CT results were negative. In some of these patients, the results of follow-up radiography at 6 weeks were also negative, suggesting that this group of patients warrants further study.  相似文献   
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The interplay between dendritic cells (DC) and T cells is a dynamic process critically depending on DC maturation. Ca(2+) influx is one of the initial events occurring during DC/T cell contacts. To determine how DC maturation influences DC/T cell contacts, time-lapse video microscopy was established using TCR-transgenic CD8(+) T cells from P14 mice. DC maturation shifted DC/T cell contacts from short-lived interactions with transient Ca(2+) influx in T cells to long-lasting interactions and sustained Ca(2+) influx of 30 min and more. Follow-up of DC/T cell interactions after 2 h using confocal microscopy revealed that long-lasting Ca(2+) responses in T cells were preferentially associated with the formation of an immunological synapse involving CD54 and H2-K(b) at the DC/T cell interface. Such synapse formation preceded MHC or B7 up-regulation, since DC developed into potent Ca(2+) stimulators 7 h after initiation of maturation. Instead, the enhanced capacity of 7 h-matured DC to induce sustained Ca(2+) responses in CD8(+) T cells is critically dependent on the polarization and rearrangement of the cytoskeleton, as shown by Clostridium difficile toxin B inhibitor experiments. These data indicate that already very early after receiving a maturation stimulus, DC display enhanced cytoskeletal activity resulting in the rapid formation of immunological synapses and effective CD8(+) T cell stimulation.  相似文献   
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