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1.
Fourteen cases of esophageal and gastric burns following the accidental ingestion of a caustic substance are presented. Early fiberoptic endoscopy was necessary, for it made possible a precise assessment of the severity and extent of injury and the application of proper conservative therapy. Signs and symptoms of caustic burns in children are an unreliable guide to injury, therefore, panendoscopy should be performed as soon as possible. A delay in the performance of a fiberoptic examination could result in the perforation of the affected organs.  相似文献   
2.
The aim of this study was early genetic identification of microcystin-producing cyanobacteria and monitoring their toxigenicity by determining toxin concentrations in three Polish lakes throughout the summer of 2004. The assessment of cyanobacterial blooms was carried out in shallow, eutrophic water bodies: Lake Jeziorak, Lake Bninskie, and Sulejow Reservoir. Samples for DNA, phycological, and toxin analyses were collected from July till October. Molecular analysis of the 16S rRNA region was used to detect cyanobacteria in water samples. The microscopic analysis was performed to investigate seasonal variation of phytoplankton. Cyanobacteria, with domination by Microcystis, Planktothrix, and Planktolyngbya were detected during the whole monitoring period in Sulejow Reservoir, Lake Bninskie, and Lake Jeziorak, respectively. The presence and identification of toxic strains in water bodies was studied by PCR amplification of mcy genes in the microcystis synthesis pathway. The presence of the mcyA, mcyB, mcyD, and mcyE genes in water samples indicated the genetic potential to produce microcystins. Toxicity of water samples and microcystin concentrations were established by PPIA and HPLC, respectively. The maximum concentration of microcystins was 11.13 microg/L and 4.67 microg/L in samples dominated by P. agardhii and M. aeruginosa, respectively. Molecular analysis showed that toxigenic strains of cyanobacteria occurred in the three lakes throughout the summer season.  相似文献   
3.
In this study we report three patients, in whom arterial hypertension was induced by compression of the kidney parenchyma due to perirenal or subcapsular hematoma following percutaneous blind renal biopsy with use of Vim-Silverman type needle.  相似文献   
4.
OBJECTIVE: Obstructive sleep apnea (OSA) is associated with obesity, sympathetic activation, systemic inflammation, and cardiovascular morbidity. Obesity, beta-adrenergic agonists, and inflammation are linked to decreased expression and/or secretion of an adipose tissue-derived antiatherogenic hormone, adiponectin. The purpose of the study was to investigate whether OSA affected plasma levels of adiponectin, which might help explain OSA-associated cardiovascular morbidity. RESEARCH METHODS AND PROCEDURES: We randomly selected 68 otherwise healthy male subjects, either with moderate/severe OSA [apnea-hypopnea index (AHI)>or=20; n=35] or without OSA (AHI相似文献   
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6.
Recombinant adenoviruses are currently being used as vectors for gene delivery to a wide variety of cells and tissues. Although generally efficacious for gene transfer in vitro, improvement in the efficiency of vector delivery in vivo may aid several gene therapy applications. One major obstacle is the lack of high-affinity viral receptors on the surface of certain cells that are targets for gene therapy. In principle, incorporation of avid, cell-specific ligands into the virion could markedly improve vector entry into the desired tissues. We have developed a strategy for addressing this issue in the lung by biopanning differentiated, ciliated airway epithelial cells against a phage display library. The peptide with the most effective binding was coupled to the surface of an adenovirus using bifunctional polyethylene glycol (PEG) molecules. The chemically modified adenoviral vector was able to effect gene transfer to well-differentiated human airway epithelial cells by an alternative pathway dependent on the incorporated peptide. Coupling of PEG to the surface of the virus also served to partially protect the virus from neutralizing antibodies in vitro. These experiments will aid in the design of improved adenoviral vectors with the capacity for more specific and efficient delivery of therapeutic genes to desired target tissues. We have used a novel method for enhancing gene delivery to target cells by coupling a biologically selected peptide to the surface of an adenovirus with bifunctional PEG molecules. Modification of the viral capsid by the addition of a peptide with binding preference for differentiated ciliated airway epithelia allowed gene delivery to those cells by a novel entry pathway. Incorporation of the CFTR gene in a similarly modified vector resulted in correction of defective Cl- transport in well-differentiated epithelial cultures established from human cystic fibrosis (CF) donors. The presence of PEG molecules on the surface of the virus served, in addition, to reduce antibody neutralization. Modification of adenoviruses with PEG/peptide complexes can serve to partially overcome the barrier of inefficient gene transfer in some cell types and some of the adverse immunological responses associated with gene delivery by these vectors.  相似文献   
7.
The 825T allele of the GNB3 gene has been associated with essential hypertension and obesity in cross-sectional studies. We have therefore planned a longitudinal cohort study to assess whether the GNB3 825T allele is predictive of blood pressure increase in young subjects with grade I hypertension. We genotyped at the GNB3 825 locus 461 participants of the Hypertension and Ambulatory Recording Venetia Study (HARVEST) study (age, 18 to 45 years) at low cardiovascular risk, according to 1999 ISH/WHO criteria. The study end point was eligibility for antihypertensive medication, that is, progression to grade II hypertension during the first year of observation or office systolic blood pressure > or =150 mm Hg and/or office diastolic blood pressure > or =95 mm Hg in two later consecutive visits during follow-up. At baseline, there was no statistically significant difference among genotypes with respect to body mass index, blood pressure, and heart rate. During follow-up (mean, 4.7 years), 113 (51.1%) patients with CC genotype and 145 (60.4%) patients with TT/TC genotype reached the end point. According to survival analysis, the patients carrying the 825T allele had an increased risk of reaching the blood pressure end point (CI, 1.108 to 1.843; P=0.006). In young patients with grade I hypertension, the 825T allele is associated with increased risk of progression to more severe hypertension requiring antihypertensive therapy. The GNB3 825T allele may be considered a genetic marker of predisposition for hypertension.  相似文献   
8.

Purpose  

Transdermal delivery of drugs is often limited by formidable barrier properties of stratum corneum (SC). Microneedles (MN) enable creation of transient microchannels in the SC and bypass this barrier. Many reports have focused on the great effectiveness of MN in improving percutaneous flux values of a variety of drugs over a large molecular size spectrum. The objective of the present study is to evaluate the influence of formulation on MN-enhanced transdermal transport of naltrexone hydrochloride (NTX HCl).  相似文献   
9.
Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a heart muscle disease characterized by myocardial necrosis followed by fibrous-fatty replacement. The pathologic process constitutes the basis for ventricular arrhythmias due to re-entrant circuits. Even if this genetic disease is transmitted in the majority of cases with autosomal dominant trait, in all reported series ARVC is prevalent in men. In this study we investigate the impact that gender may have on clinical presentation in a large series of patients with ARVC. A total of 171 consecutive patients (mean 29 +/- 12 years, range 13 to 65) affected by ARVC were examined with family and personal history, 12-lead electrocardiogram (ECG), 24-hour ECG, signal-averaged ECG, and echocardiogram. Moreover, electrophysiological study and ventricular angiography were performed in selected cases. In the 171 subjects, 71% were men and 29% women (p = 0.02). No gender differences were found considering the age at the time of diagnosis and of study enrolment and the prevalence of index cases and family members. The genders differed in prevalence of abnormal ECG (69% vs 52%, p = 0.036) and presence of late potentials (60% vs 40%, p = 0.01). Moreover, men had larger right ventricular dimensions and practiced competitive sports more frequently (26% vs 14%, p <0.001). Nonetheless, gender was not associated with a high incidence of life-threatening ventricular arrhythmias or with a poor outcome. In conclusion, our data show that diagnosis of ARVC is less common in female patients, who present a higher prevalence of mild forms. Nonetheless, the degree of electrical instability does not differ significantly between genders in affected subjects. Even if ARVC remains mainly a male disease, gender does not have a role in patients' outcome. The cause of the under-representation of women is not clear, even if potentially important factors such as sexual hormones and physical activity could play a role.  相似文献   
10.
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