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41.
42.
Lucas  KG; Small  TN; Heller  G; Dupont  B; O'Reilly  RJ 《Blood》1996,87(6):2594-2603
Epstein-Barr virus-induced lymphoproliferative disease (EBV-LPD) is a potentially lethal complication during the first 6 months after allogeneic bone marrow transplantation (BMT). To determine whether deficiencies of EBV-specific cellular immunity contribute to EBV-LPD susceptibility and distinguish patients at risk, we performed limiting dilution analysis to quantify anti-EBV cytotoxic T-lymphocyte precursor (CTLp) frequencies in 26 recipients of unmodified or T-cell-depleted (TCD) grafts from EBV-seropositive donors. At 3 months post-BMT (n = 26), only five patients had EBV CTLp frequencies in the range of seropositive normal controls, irrespective of the type of transplant administered. By 6 months post-BMT, 9 of 13 patients tested had EBV CTLp frequencies within the normal range. The time period in which these patients had deficient cellular immunity to EBV corresponds to the period in which we have observed EBV-LPD in most prior patients. One patient with a low EBV CTLp frequency at 4 months post-BMT developed an EBV-LPD. Within 2 weeks of receiving an infusion of donor peripheral blood mononuclear cells (PBMC) providing less than 1,200 EBV- specific cytotoxic T-cell precursors, populations of EBV-specific CTL in the circulation were restored to levels detected in normal seropositive adults. Concurrently, the patient achieved a regression of the EBV-LPD, which has been sustained without further therapy. These studies indicate that recipients of both unmodified and TCD marrow grafts have profound deficiencies of EBV-specific T cell-mediated immunity early posttransplant, and that the period of risk for EBV-LPD closely corresponds to this interval of severe deficiency. Treatment of one patient with EBV-LPD with marrow donor-derived PBMC induced a rapid expansion of EBV-specific cytotoxic T-cell populations that occurred contemporaneously with the clinical regression of disease.  相似文献   
43.
Kirschbaum  NE; Gumina  RJ; Newman  PJ 《Blood》1994,84(12):4028-4037
Platelet endothelial cell adhesion molecule-1 (PECAM-1) is a cell-cell adhesion molecule that is expressed on circulating platelets, on leukocytes, and at the intercellular junctions of vascular endothelial cells and mediates the interactions of these cells during the process of transendothelial cell migration. The cDNA for PECAM-1 encodes an open reading frame of 738 amino acids (aa) that is organized into a 27- aa signal peptide, a 574-aa extracellular domain composed of 6 Ig homology units, and a relatively long cytoplasmic tail of 118 aa containing multiple sites for posttranslational modification and postreceptor signal transduction. To provide a molecular basis for the precise evaluation of the structure and function of this transmembrane glycoprotein, we have determined the organization of the human PECAM-1 gene. The PECAM-1 gene, which has been localized to human chromosome 17, is a single-copy gene of approximately 65 kb in length and is broken into 16 exons by introns ranging in size from 86 to greater than 12,000 bp in length. Typical of other members of the Ig superfamily, each of the extracellular Ig homology domains is encoded by a separate exon, consistent with PECAM-1 having arisen by gene duplication and exon shuffling of ancestral Ig superfamily genes. However, the cytoplasmic domain was found to be surprisingly complex, being encoded by seven short exons that may represent discrete functional entities. Alternative splicing of the cytoplasmic tail appears to generate multiple PECAM-1 isoforms that may regulate phosphorylation, cytoskeletal association, and affinity modulation of the mature protein. Finally, a processed pseudogene having 76% identity with PECAM- 1 cDNA was identified and localized to human chromosome 3. These findings should have important implications for structure/function analysis of PECAM-1 and its role in vascular adhesive interactions.  相似文献   
44.
Chronic orofacial pain of neuropathic origin can present diagnostic and management dilemmas to dental practitioners and also affects the patient's quality of life. Intracranial aneurysms are a potential cause of stroke (e.g. sub‐arachnoid haemorrhage) that is usually associated with, high rates of mortality and morbidity. A patient who had been previously managed for symptoms of temporomandibular joint disorder (TMD) presented with sharp, shooting pain of moderate intensity. It was precipitated by swallowing, and radiated to the right throat, posterior border of the mandible, ear and temporomandibular joint. Clinical and radiological investigations ruled out odontogenic pain, TMD and other more common types of facial pain. Magnetic resonance imaging revealed a 7 × 6 mm aneurysm in the right middle cerebral artery (MCA) which was subsequently surgically clipped. Interestingly, the facial pain resolved after this procedure. Compression of the insular region of the brain innervated by the trigeminal, glossopharyngeal and vagus nerves provides a plausible explanation for the pain reported. To our knowledge, this is the first case of facial neuralgia associated with an aneurysm in the MCA which emphasizes the importance of a multidisciplinary approach in the diagnosis and management of unusual cases of chronic orofacial pain.  相似文献   
45.
Foreign body removal has been developed as a routine radiology department service. Techniques, indications and hazards are described.  相似文献   
46.
AIMS: To investigate the differences in perception of quality of life between parents of chronically ill children and paediatricians at diagnosis and follow up. Quality of life was assessed using the (HUI3). METHODS: Longitudinal study (July 1999-January 2002) of 37 paediatricians and 181 parents of patients (children aged 1-17 years) with cystic fibrosis admitted for a pneumonia or patients with newly diagnosed acute lymphatic leukaemia, juvenile idiopathic arthritis, or asthma. Main outcome measure was percentage agreement on the attributes of the HUI3 between parents and paediatricians. RESULTS: Differences in perception of health and wellbeing between paediatricians and parents of children with a chronic disease were found, not only at diagnosis but also after a period of follow up. Differences were particularly clear in the subjective attributes emotion (range of agreement 28-68%) and pain/discomfort (range of agreement 11-33%). In all patient groups, at baseline and follow up, the paediatrician assessed the patient to have less pain/discomfort in comparison to the parents. Despite a prolonged patient- paediatrician relationship, differences at follow up did not decrease compared to baseline. CONCLUSION: At the onset of a chronic disease, but also after a period of follow up, quality of life of paediatric patients may be misunderstood by healthcare professionals, especially in the subjective attributes. Systematic assessment of quality of life may contribute to better understanding between physicians and parents.  相似文献   
47.
Lung cancer is not commonly known to metastasise to the perirenal space, with only five such cases previously published. We present an unusual case of perirenal lung metastases manifesting as diffuse perinephric stranding which to our knowledge has not been described before.  相似文献   
48.
The majority of breast cancer research is conducted using established breast cancer cell lines as in vitro models. An alternative is to use cultures established from primary breast tumours. Here, we discuss the pros and cons of using both of these models in translational breast cancer research.  相似文献   
49.
To assess the pediatric risk of mortality (PRISM) score as a prognostic scoring system in severe meningococcal disease, the files of 53 consecutive patients admitted to a tertiary pediatric intensive care with a clinical diagnosis of meningococcal disease and positive cultures from blood and/or cerebrospinal fluid were analysed. PRISM-score-based expected mortality was compared with observed mortality. Expected mortality in the whole study population was 29% while observed mortality was 19% (P < 0.05). The highest expected and observed mortality was found in septicaemic patients without (documented) meningitis, while meningitis patients without septicaemia had the lowest mortality. All patients with a mortality risk below 18.3% (n = 29) survived whereas all those with a mortality risk of 65% or higher (n = 7) died. Of the 17 patients with a mortality risk between 18.3% and 63.9%, 14 survived and 3 died. The area under the receiver-operating characteristic (ROC) curve was 0.94, which is at least comparable with the best-performing meningococcal-disease-specific scoring systems. Conclusion The PRISM score is a useful generic measure of severity of illness in meningococcal disease and can be used to determine the effectiveness of different treatment strategies. Received: 5 May 1999 / Accepted: 11 January 2000  相似文献   
50.
Paracetamol is the commonest agent employed in self poisoning, however it is not clear whether adolescents possess insight into the serious complications associated with its misuse. Using a one page questionnaire, the availability, usage, and knowledge of toxicity of paracetamol among 1147 American and British adolescents was assessed. Although 90% of all students recognised that paracetamol could kill, the great majority of students overestimated the lethal dose. In addition, while knowledge regarding side effects of paracetamol was poor the drug was widely available to, and used by, the study population. It is proposed that gross overestimation of the number of tablets required to kill, poor understanding of paracetamol side effects, and wide availability of the drug contribute to its frequent use in adolescent suicidal behaviour. The inclusion of some over-the-counter medications in school drug education programs in addition to tighter control of the availability of paracetamol may help reduce the problem of adolescent self poisoning.  相似文献   
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