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61.
Systemic corticosteroid therapy is an established adjunct to beta-adrenergic medications in acute exacerbations of asthma. To date, no study has defined the role of long-acting intramuscular preparations of corticosteroids in pediatric patients with asthma. A pilot study was conducted to prospectively compare symptomatic improvement following a single injection of intramuscular dexamethasone (IMD) to a 3-day regimen of oral prednisone (OP) for children with mild to moderate wheezing episodes that are responsive to nebulized medications in the Pediatric Emergency Department (PED). The following children presenting with acute exacerbations of asthma to the PED were eligible for enrollment: age 3-16 years; more than two prior wheezing episodes; mild to moderate wheezing; and oxygen saturation 95% or more in room air. The study patients were randomly assigned to receive either IMD (n = 21) or OP (n = 21) in addition to a standardized treatment regimen of nebulized albuterol. All of the children were clinically rated for wheezing severity by the Pulmonary Index (PI) score at regular intervals during the study. Discharge home was based on clinical improvement during treatment in the PED; patients who were admitted to the hospital were removed from the study. Follow-up was conducted the fifth day after discharge from the ED either by clinic visit or by telephone. Patients were assessed for symptomatic improvement and relapse or clinical deterioration during the study period by a clinician blinded to group assignment. Forty-two children participated in this pilot study. There were no significant differences between the IMD and OP groups for gender or age. Mean ages were: 82 months (SD 46 months), IMD group; 63 months (SD 36 months), OP group. Clinical progress (based on PI) with treatment in the PED was the same in both groups: pretreatment median, PI = 6; PED discharge median, PI = 2. None of the study patients were hospitalized during the follow-up period, and all reported symptomatic improvement since initial treatment. The data of this pilot study suggest that IMD may be a feasible alternative to OP for treatment of acute wheezing episodes in children with asthma. IMD provides sufficient treatment to prevent clinical deterioration within 5 days after initial therapy for mild to moderate pediatric exacerbations of asthma that are responsive to nebulized medications.  相似文献   
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The SLT2(MPK1) mitogen-activated protein kinase signal transduction pa thway has been implicated in several biological processes in Saccharomyces cerevisiae, including the regulation of cytoskeletal and cell wall structure, polarized cell growth, and response to nutrient availability, hypo-osmotic shock and heat shock. We examined the conditions under which the SLT2 pathway is activated. We found that the SLT2 kinase is tyrosine phosphorylated and activated during periods in which yeast cells are undergoing polarized cell growth, namely during bud formation of vegetative cell division and during projection formation upon treatment with mating pheromone. BCK1(SLK1), a MEK kinase, is required for SLT2 activation in both of these situations. Upstream of BCK1(SLK1), we found that the STE20 kinase was required for SLT2 activation by mating pheromone, but was unnecessary for its activation during the vegetative cell cycle. Finally, SLT2 activation during vegetative growth was partially dependent on CDC28 in that the stimulation of SLT2 tyrosine phosphorylation was significantly reduced directly after a temperature shift in cdc28 ts mutants. Our data are consistent with a role for SLT2 in promoting polarized cell growth.  相似文献   
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Toxicity to nontumor-derived tissue has proven to be a significant obstacle in achieving therapeutic levels of gamma irradiation in the treatment of cancer. The formation of reactive oxygen species (ROS) such as superoxide radicals (O2-) following irradiation is thought to be a major determinant of cellular damage. To this end, we describe the generation of two recombinant adenoviral vectors expressing the radical-scavenging enzymes MnSOD and CuZnSOD to test therapeutic strategies of radioprotection. Using a human lung epithelial cell line (IB-3), we have demonstrated that infections with both Ad.CMVMnSOD or Ad.CMVCuZnSOD significantly increase both the levels of SOD protein and enzymatic activity as compared to control cells. This increase in SOD expression reduced the level of apoptosis at 72 hr post-irradiation by 50% as compared to mock- or Ad.CMVLacZ-infected cells. Such studies provide the foundation for radioprotective gene therapies in the treatment of cancer.  相似文献   
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In the present study, the removal and immobilization of 137Cs from aqueous waste solutions and a simulated waste was investigated. Two inorganic ion‐exchange complexes: di‐potassium hexacyanocobalt(II)‐ferrate(II), K2CoFe(CN)xH2O (KCFC), and ammonium‐12‐molybdophosphate [(NH4)3PMo12O40·aq] (AMP), were charged separately into porous nylon bags (sorption bags) of 5 µm pore diameter. The first complex (KCFC) was prepared in our laboratory. The second (AMP) was used for comparison. Easy handling and increased potential for reuse characterize the sorption bag technique. The KCFC complex was investigated by thermal gravimetric analysis (TGA) and differential thermal analysis (DTA), porosity, infra‐red (IR) and X‐ray powder diffraction (XRD). The chemical and structural investigations revealed that the KCFC complex has adequate ion‐exchange capacity and high affinity for 137Cs. The sorption bag technique showed promising results for the removal of 137Cs from aqueous waste solutions. The KCFC bags showed the highest 137Cs removal (~0.91 g g?1), at pH 8.5; AMP bags gave the highest 137Cs removal (~0.97 g g?1) in 0.1 N HNO3 and 1.5 N HNO3, both with a waste: sorbent ratio of 80 cm3 g?1. Sorption data for both KCFC and AMP revealed a good fit to the Freundlich sorption isotherm. To assess the potential of sorption bags, the used bags were regenerated in different leachants and reused in further sorption investigations. 137Cs recovery from the used sorbents was ~0.46 g g?1 using 6 N HCl as leachant for AMP, compared with ~0.253 g g?1 for KCFC using 6 N NaCl. These results indicated stronger cesium immobilization in the KCFC complex. Copyright © 2003 Society of Chemical Industry  相似文献   
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Good survival rates have been reported for resected early gastric adenocarcinoma (EGC) in patients found via screening procedures. However, the prevalence of Helicobacter pylori in EGC in unscreened populations is unclear. The major purpose of this investigation was to analyze the clinical experience and incidence of H. pylori in unscreened patients presenting with EGC at Charity Hospital over a 34-year period. From 1963 through 1997, the tumor registry at Charity Hospital compiled data on 2497 patients evaluated for gastric carcinoma. Of these patients, 26 (1%) had lesions that were confined to the mucosa or submucosa, i.e., T1N0M0 (American Joint Commission on Cancer classification). Pathology specimens and medical records were retrieved for confirmation of diagnosis and retrospective analysis for H. pylori. H. pylori was analyzed by Steiner staining and immunohistochemistry using a polyclonal antibody. EGC was detected in 12 men and 14 women with a mean age of 62 years. Upper gastrointestinal X-ray studies were performed on 19 of the 26 patients and failed to conclusively demonstrate a lesion in any case. Endoscopy was performed on 22 patients, and preoperative biopsies were positive in 95 per cent of these. Operative procedures included 2 local excisions and 22 subtotal and 2 total gastrectomies. No extended nodal dissections were performed. Microscopic evaluation revealed lesions limited to the mucosa in 63 per cent of cases and involving the submucosa in 37 per cent of the cases. Of the 14 patients evaluable of H. pylori, 79 per cent were positive for the bacterium. The status of 2 patients is unknown, and only 1 patient died of the original gastric cancer, for a disease-free survival of 96 per cent. The 5-year and 10-year overall survival rates were calculated to be 50 per cent and 21 per cent, respectively, when all causes of death were taken into consideration. Median follow-up of the survivors was 64 months. Resection of early gastric carcinoma in unscreened patients without extended lymphadenectomy yielded excellent results. H. pylori was present in 79 per cent of cases. These data suggest an association between H. pylori and EGC. Whether H. pylori infection is an etiologic factor in gastric cancer remains an area of active research.  相似文献   
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