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61.
OBJECTIVES: To determine the spectrum of N and G genotypes of respiratory syncytial virus (RSV) causing respiratory tract infection and whether particular genotypes are associated with severity of infection. PATIENTS AND METHODS: Nasopharyngeal aspirates (NPAs) were obtained from 114 infants with acute respiratory tract infection due to RSV over two seasons. Viral mRNA was extracted from NPAs or cultured virus, reverse transcribed, and the cDNA amplified by the polymerase chain reaction using primers directed to parts of the N and G gene respectively. Amplicons were separately digested with four different restriction endonucleases for each gene. The fragments were separated by agarose gel, electrophoresis, and the electrophoretic patterns used to assign the various genotypes. Disease severity was assessed as very mild (upper respiratory tract signs only), mild (coryza and signs of lower respiratory tract infection), moderate (requiring nasogastric or intravenous fluids), and severe (requiring oxygen or ventilation). RESULTS: Five of the six known N genotypes were detected, but NP4 and NP2 were found most frequently. There was no association between N genotype and disease severity. Six G (SHL) genotypes were detected. Significantly (p = 0.04) more of the infants infected with the SHL2 genotype had severe or moderate disease. CONCLUSIONS: During the seasonal peaks of RSV respiratory tract infection at least 10 different RSV genotypes cocirculated. While there is no association between N genotypes and disease severity, infection with the SHL2 G genotype appears to result in moderate to severe disease.  相似文献   
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Postoperative pain in children with spastic cerebral palsy (CP) is often attributed to muscle spasm and is difficult to manage using opiates and benzodiazepines. Adductor-release surgery to treat or prevent hip dislocation in children with spastic CP is frequently performed and is often accompanied by severe postoperative pain and spasm. A double-blinded, randomized, placebo-controlled clinical trial of 16 patients (mean age 4.7 years) with a mainly spastic type of CP (either diplegic or quadriplegic in distribution) was used to test the hypothesis that a significant proportion of postoperative pain is secondary to muscle spasm and, therefore, might be reduced by a preoperative chemodenervation of the target surgical muscle by intramuscular injection of botulinum toxin A (BTX/A). Compared with the placebo, BTX/A was found to be associated with a reduction in mean pain scores of 74% (P<0.003), a reduction in mean analgesic requirements of approximately 50% (P<0.005), and a reduction in mean length of hospital admission of 33% (P<0.003). It was concluded that an important component of postoperative pain in the patient population is due to muscle spasm and this can be managed effectively by preoperative injection with BTX/A. These findings may have implications for the management of pain secondary to muscle spasm in other clinical settings.  相似文献   
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Gene expression of antioxidant enzymes in experimental diabetic neuropathy   总被引:6,自引:0,他引:6  
Chronic hyperglycemia results in a large deficit in nerve blood flow. Both autoxidative- and ischemia-induced lipid peroxidation occurs, with resultant peripheral sensory neuropathy in streptozotocin-induced diabetes in the rat. Free radical defenses, especially involving antioxidant enzymes, have been suggested to be reduced, but scant information is available on chronic hyperglycemia. We evaluated the gene expression of glutathione peroxidase, catalase, and superoxide dismutase (cuprozinc and manganese separately) in L4,5 dorsal root ganglion (DRG) and superior cervical ganglion, as well as enzyme activity of glutathione peroxidase in DRG and sciatic nerve in experimental diabetic neuropathy of 3 months and 12 months durations. We also evaluated nerve electrophysiology of caudal, sciatic-tibial, and digital nerves. A nerve conduction deficit was seen in all nerves in experimental diabetic neuropathy at both 3 and 12 months. Gene expression of glutathione peroxidase, catalase, cuprozinc superoxide dismutase, and manganese superoxide dismutase were not reduced in experimental diabetic neuropathy at either 3 or 12 months. Catalase mRNA was significantly increased in experimental diabetic neuropathy at 12 months. Glutathione peroxidase enzyme activity was normal in sciatic nerve. We conclude that gene expression is not reduced in peripheral nerve tissues in very chronic experimental diabetic neuropathy. Changes in enzyme activity may be related to duration of diabetes or due to post-translational modifications.  相似文献   
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The effectiveness of postoperative radiotherapy (PORT) in improving outcomes remains debatable for oral squamous cell carcinoma (OSCC) patients with pathological intermediate-risk factors (IRFs) after surgery. A retrospective analysis was conducted on 432 intermediate-risk OSCC patients defined by histological reporting of close margin (<5 mm), early nodal disease (pN1), depth of invasion/tumour thickness ≥5 mm, perineural invasion, and/or lymphovascular invasion. Outcomes measured were disease-free survival (DFS), disease-specific survival (DSS), and overall survival (OS). PORT was associated with an improvement in 5-year DFS on univariable analysis (80% vs 71%; P = 0.044), but this did not remain significant on multivariable analysis. PORT was not associated with differences in DSS or OS. The surgical salvage rate was similar in the PORT and surgery-only groups (41% vs 47%; P = 0.972). Perineural invasion was found to be an independent predictor of inferior DSS (hazard ratio (HR) 2.19), DFS (HR 1.89), and OS (HR 1.97). Significantly worse outcomes were observed for patients with ≥4 concurrent IRFs. The application of PORT was associated with lower rates of recurrence, but the benefit was less apparent on mortality. Patients with perineural invasion and multiple concurrent IRFs were found to be at greatest risk, representing a subset of intermediate-risk OSCC patients who may benefit from PORT.  相似文献   
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The purpose of this study was to investigate homeless youth mobile phone and social media use, to plan health promotion efforts. Nearly half (46.7%) of runaway/homeless youth in this sample (n = 181) owned a mobile phone and a majority of those devices were smart phones. Ownership did not vary significantly by shelter location, though regular use of Facebook was more prevalent among those in housing programs or camping, than those living on the streets. Over 90% of youth in the sample reported using Facebook. Such media use might facilitate parent, family, and health provider communications with homeless youth.  相似文献   
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