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171.
Tracheobronchial stenosis in infants: successful balloon dilation therapy   总被引:2,自引:0,他引:2  
Four infants with congenital or acquired tracheobronchial stenosis were successfully treated with angioplasty balloon catheter dilation. The technical details and complications of these procedures are described. The authors believe balloon dilation therapy should be considered as the initial form of therapy for tracheal stenosis in infants, even in the presence of complex stenotic lesions.  相似文献   
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A prospective phase II trial was conducted to assess the feasibility, tolerance, and efficacy of a device designed for selective removal of rheumatoid factor from the plasma of rheumatoid arthritis patients. The device contained terpolymer hydrogel-coated plates with chemically attached, aggregated human immunoglobulin G, and it operated as an immunoaffinity column. Sixty-one patients aged 25 to 73 underwent weekly plasmapheresis treatments (the primary therapy phase). During the trial, patients continued current rheumatoid arthritis medications without dose adjustments. All patients received two to six treatments (primary therapy). Responding patients were eligible to continue apheresis treatment every 2 to 6 weeks (maintenance therapy). No serious, untoward side effects were noted in the course of this study; of 640 treatments, only 2 (in different patients) were aborted, one because of complaints of dizziness and angioedema and the other because of chest tightness and shortness of breath. Except for a significant (p less than 0.05) decrease in serum iron, no significant changes in complete blood count, serum electrolytes, renal and hepatic function tests, or serum C3 and C4 were noted. Although the trial was not designed to determine clinical efficacy, patients noted less morning stiffness, longer time to onset of fatigue, and improved global pain assessment (p less than 0.004); significant objective improvements were noted in joint pain, tenderness, swelling, and the number of affected joints (p less than 0.001). One-half of the treated patients had at least a 50 percent improvement in objective measures of antirheumatic activity.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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The blood-brain barrier (BBB) maintains the brain homeostasis and dynamically responds to events associated with systemic and/or rheological impairments (e.g., inflammation, ischemia) including the exposure to harmful xenobiotics. Thus, understanding the BBB physiology is crucial for the resolution of major central nervous system CNS) disorders challenging both health care providers and the pharmaceutical industry. These challenges include drug delivery to the brain, neurological disorders, toxicological studies, and biodefense. Studies aimed at advancing our understanding of CNS diseases and promoting the development of more effective therapeutics are primarily performed in laboratory animals. However, there are major hindering factors inherent to in vivo studies such as cost, limited throughput and translational significance to humans. These factors promoted the development of alternative in vitro strategies for studying the physiology and pathophysiology of the BBB in relation to brain disorders as well as screening tools to aid in the development of novel CNS drugs. Herein, we provide a detailed review including pros and cons of current and prospective technologies for modelling the BBB in vitro including ex situ, cell based and computational (in silico) models. A special section is dedicated to microfluidic systems including micro-BBB, BBB-on-a-chip, Neurovascular Unit-on-a-Chip and Synthetic Microvasculature Blood-brain Barrier.  相似文献   
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Identifying the level of overpressure required to create physiological deficits is vital to advance prevention, diagnostic, and treatment strategies for individuals exposed to blasts. In this study, a rodent model of primary blast neurotrauma was employed to determine the pressure at which acute neurological alterations occurred. Rats were exposed to a single low intensity shock wave at a pressure of 0, 97, 117, or 153 kPa. Following exposure, rats were assessed for acute cognitive alterations using the Morris water maze and motor dysfunction using the horizontal ladder test. Subsequently, histological analyses of three brain regions (primary motor cortex, the hippocampal dentate gyrus region, and the posteromedial cortical amygdala) were conducted. Histological parameters included measuring the levels of glial fibrillary acidic protein (GFAP) to identify astrocyte activation, cleaved caspase-3 for early apoptosis identification and Fluoro-Jade B (FJB) which labels degenerating neurons within the brain tissue. The results demonstrated that an exposure to a single 117 kPa shock wave revealed a significant change in overall neurological deficits when compared to controls and the other pressures. The animals showed significant alterations in water maze parameters and a histological increase in the number of GFAP, caspase-3, and FJB-positive cells. It is suggested that when exposed to a low level shock wave, there may be a biomechanical response elicited by a specific pressure range which can cause low level neurological deficits within the rat. These data indicate that neurotrauma induced from a shock wave may lead to cognitive deficits in short-term learning and memory of rats. Additional histological evidence supports significant and diffuse glial activation and cellular damage. Further investigation into the biomechanical aspects of shock wave exposure is required to elucidate this pressure range-specific phenomenon.  相似文献   
179.

Objective

To investigate the ability of the methanolic extract of pineapple peel to modulate alcohol-induced lipid peroxidation, changes in catalase activities and hepatic biochemical marker levels in blood plasma.

Methods

Oxidative stress was induced by oral administration of ethanol (20% w/v) at a dosage of 5 mL/kg bw in rats. After 28 days of treatment, the rats were fasted overnight and sacrificed by cervical dislocation. Blood was collected with a 2 mL syringe by cardiac puncture and was centrifuged at 3 000 rpm for 10 min. The plasma was analyzed to evaluate malondialdehyde (MDA), catalase activity, aspartate aminotransferase (AST), alkaline phosphatase (ALP) and alanine aminotransferase (ALT) concentrations.

Results

Administration of alcohol caused a drastic increase (87.74%) in MDA level compared with the control. Pineapple peel extract significantly reduced the MDA level by 60.16% at 2.5 mL/kg bw. Rats fed alcohol only had the highest catalase activity, treatment with pineapple peel extract at 2.5 mL/kg bw however, reduced the activity. Increased AST, ALP and ALT activities were observed in rats fed alcohol only respectively, treatment with pineapple peel extract drastically reduced their activities.

Conclusions

The positive modulation of lipid peroxidation, catalase activities as well as hepatic biomarker levels of blood plasma by the methanolic extract of pineapple peels under alcohol-induced oxidative stress is an indication of its protective ability in the management of alcohol-induced toxicity.  相似文献   
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