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The aim of the study was to assess if lung function at birth predicts lung function at 2 yr and secondly, if lung function development was influenced by the common phenotypes of recurrent bronchial obstruction (rBO) or atopic eczema (AE) by 2 yr. Lung function was assessed at birth (n = 802) and at 2 yr within the prospective birth cohort study 'the Environment and Childhood Asthma Study' in Oslo. The 135 children with lung function measured at birth by tidal flow volume (TFV) loops and passive respiratory mechanics, who were included in a nested case-control study were reinvestigated at 2 yr with clinical examination, TFV loops (n = 90) (mean age 26.6 (3.7 s.d.) months), skin prick test and parental interview. Children were categorized into quartiles (lower, middle two, upper) according to time to peak tidal expiratory flow/total expiratory time (t(PTEF)/t(E)) at birth as well as clinical phenotype based on the presence of rBO and/or AE (ever) by 2 yr. The observed reduction in mean t(PTEF)/t(E) from birth to 2 yr within the quartiles, were not significantly different after controlling for 'regression to the mean'. t(PTEF)/t(E) at birth correlated significantly with t(PTEF)/t(E) at 2 yr, (r = 0.475, p < 0.001). Children with both rBO and AE by 2 yr had significantly lower t(PTEF)/t(E) at 2 yr (p = 0.002) and at birth (p = 0.027), compared with children with no rBO or AE. Clinical phenotype at 2 yr did not influence the change in t(PTEF)/t(E) from birth to 2 yr. This study demonstrates a clear tracking of lung function from birth, not influenced by rBO or AE by 2 yr.  相似文献   
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Experimental gene therapy is a promising strategy to prevent ischemia-reperfusion (I/R) injury and allograft rejection after lung transplantation, and methods will eventually be needed to characterize pulmonary transgene expression in vivo in humans. Therefore, we studied positron emission tomography (PET) as a means of performing in vivo molecular imaging in rodent models of lung transplantation. Rats were transfected endotracheally with adenovirus encoding a fusion gene of a mutant Herpes simplex virus-1 thymidine kinase and the green fluorescent protein gene (the former serving as an imaging reporter gene). Twenty-four hours after transfection, lungs were transplanted in groups representing normal transplantation, I/R injury and acute allograft rejection. Imaging was obtained either 24 h after transplantation to study reperfusion injury or 4 days after transplantation to study graft rejection. After imaging, lungs were excised and analyzed for thymidine kinase activity. Imaging detected transgene expression in transplanted lungs even in the presence of acute rejection or I/R injury. The PET imaging signal correlated with in vitro lung tissue assays of thymidine kinase activity (r(2) = 0.534). Thus, noninvasive molecular imaging with PET is a feasible, sensitive and quantitative method for characterizing pulmonary transgene expression in experimental lung transplantation.  相似文献   
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Ultrafiltration and solute transport during 60-min peritoneal dialyses of normal rabbits with intraperitoneal administration of phosphatidylcholine were compared to control values. The ultrafiltration rate of 0.27 mL/Kg/min did not increase when phosphatidylcholine was added. This agent had no effect on the ultrafiltration coefficient, sodium mass transport or solute clearances. Previously reported beneficial results with this agent could be due to repletion of a deficiency or an effect of the organic solvent. More studies of safety and efficacy of phosphatidylcholine are warranted before widespread clinical use.  相似文献   
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Phaeohyphomycosis is a disease caused by dematiaceous fungi. Here, the first culture-proven case of mediastinal mass due to Fonsecaea pedrosoi is reported. The patient was a 40-yr-old male who had presented with history of dyspnoea and dysphagia. Computed tomography of the chest disclosed a mediastinal mass. Cultures of a specimen from the mediastinum grew Fonsecaea pedrosoi. The patient received amphotericin B and itraconazole and showed a remarkable recovery. Repeat computed tomography revealed a reduction in the mediastinal mass. The case highlights the need for a high degree of clinical suspicion and appropriate histopathological and mycological examination of clinical specimens.  相似文献   
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Oxygen free radicals (OFR) are implicated in thepathogenesis of stress, chemically induced gastriclesions, and gastrointestinal injury. Theconcentration-dependent scavenging abilities of bismuthsubsalicylate (SBS), colloidal bismuth subcitrate (CBS), andselected OFR scavengers, including superoxide dismutase(SOD), catalase, mannitol, and allopurinol were examinedagainst biochemically or chemically generated superoxide anion, hydroxyl radical, andhypochlorite radical plus hypochlorous acid based on achemiluminescence assay. Furthermore, both gastric (GM)and intestinal mucosa (IM) were individually exposed in vitro to these free radical generatingsystems, and the concentration-dependent protectiveabilities of SBS and CBS against lipid peroxidation (LP)were compared with selected OFR scavengers. In addition, 24-hr fasted rats were orally treated with thenecrotizing agents 0.6 M HCl, 0.2 M NaOH, 80% ethanol,and aspirin (200 mg/kg). The extent of tissue injury inthe GM and IM was determined by assessing LP, DNA fragmentation, and membrane microviscosity.Dose- and time-dependent in vivo protective abilities ofCBS (100 mg/kg) and SBS (15 mg/kg) were also assessed.Following incubations with superoxide anion and hydroxyl radical generating systems in thepresence of 125 mg SBS/liter, approximately 47% and 61%inhibitions were observed in the chemiluminescenceresponse, respectively, while 48% and 46% inhibitions were observed with 125 mg CBS/liter. SBS andCBS exerted similar abilities towards hypochloriteradical plus hypochlorous acid. Approx. 3.1- and3.7-fold increases in LP were observed in the GM and IMof rats following oral administration of 0.6 MHCl. Pretreatment of the rats with SBS and CBS decreased0.6 M HCl-induced LP in the GM by approx. 39% and 27%,respectively, with similar decreases in LP in the IM. SBS exhibited better protectiveabilities towards 0.6 M HCl and 0.2 m NaOH-induced GMand IM injury as compared to CBS. SBS and CBS providedsimilar protection towards 80% ethanol-induced gastric injury, while CBS exerted a superior protectiveability towards aspirin-induced gastric injury. Theresults demonstrate that both SBS and CBS can scavengereactive oxygen species and prevent tissue damage produced by OFR.  相似文献   
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The preventive effect of the aldose reductase inhibitor (ARI) ponalrestat on heart-rate variability and the development of autonomic neuropathy in the vagus nerve was investigated in the spontaneously diabetic BB rat. ARI treatment completely prevented the characteristic decrease in heart-rate variability and axonal atrophy of the vagus nerve for 4 mo in hyperglycemic BB rats. After 6 mo of treatment, the preventive effect on heart-rate variability was partial, and the vagus nerve demonstrated an increase in regenerating myelinated and unmyelinated fibers. These data suggest that autonomic neuropathy involving the vagus nerve is metabolically induced by demonstrating that inhibition of the polyol pathway significantly delays the occurrence of functional and structural autonomic neuropathy despite the presence of hyperglycemia.  相似文献   
9.
Candidaemia: a 10-year study in an Indian teaching hospital   总被引:3,自引:0,他引:3  
Retrospective evaluation of candidaemia patients was performed in an Indian teaching hospital over a 10-year period. The incidence of patients with candidaemia increased eleven-fold in the second half of the study period (55 patients) compared with the first half (5 patients). Haematological malignancies (11 patients), neonatal septicaemia (9), cardiac abnormalities and cardiac surgery (9) were the commonest underlying diseases in these patients. Candida albicans (50%), C. guilliermondii (17%), C. tropicalis (15%) and C. parapsilosis (8%) were the most common fungal pathogens isolated from blood culture. Therapy with two or more antibiotics (92%), corticosteroid administration (25%), intravascular catheter use for over 24 h (78%) and neutropenia (48%) were the accountable predisposing factors. Prolonged hospitalization (mean average 22.2 days as compared with 11.2 days in other patients) was an added risk factor in these patients.  相似文献   
10.
Surgical treatment of intracavernous neoplasms: a four-year experience   总被引:1,自引:0,他引:1  
Forty-two patients with neoplasms involving the cavernous sinus had operations between 1983 and 1987. The lesions included 25 benign tumors (e.g., meningioma, neurilemoma) and 17 malignant tumors (e.g., chondrosarcoma, adenoid cystic carcinoma). The cavernous sinus was entered by inferior, anterolateral, or medial extradural approaches or by superior or lateral intradural approaches. The intracavernous internal carotid artery was managed by dissecting tumor away from it or by occlusion and excision with or without direct vein graft reconstruction, based on the results of a preoperative balloon occlusion test. Cranial nerves III, IV, V, and VI usually were dissected from tumor, but in 3 cases of tumor invasion, the excised nerve segment was reconstructed by direct suture or with a sural nerve interposition graft. Twenty-one of the benign tumors and 8 of the malignant tumors were excised totally and the remainder subtotally. On follow-up ranging from 3 to 48 months, one subtotally excised meningioma recurred and was treated with re-excision and adjuvant radiation therapy. Two "totally" excised malignant tumors recurred outside the cavernous sinus at the margins of excision. There was no operative mortality or permanent cerebral morbidity. Postoperatively, the ocular and neurological function of most patients was similar to the preoperative status; in some, it was significantly improved. Thirteen additional patients with intracavernous neoplasms also were evaluated during the same period and followed without operation. The early follow-up information regarding these patients is provided.  相似文献   
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