摘要:

Carbon monoxide intoxication decreases systemic blood pressure and peripheral resistance. In order to assess the role of the skin in this process, we measured the perfusion of hind limb shaven skin in anaesthetized rats during acute moderate carbon monoxide intoxication. At a steady blood level of 25% carboxyhaemoglobin, the red blood cell flux was measured as an index of tissue perfusion, using laser Doppler fluxmetry. The mean blood pressure decreased by 30% during carbon monoxide exposure, but there was no change in mean red blood cell flux of the hind limb skin microvessel bed. Thus, rat hind limb skin perfusion was not affected by acute moderate steady state carbon monoxide intoxication.

ISSN:0167-6865    

DOI:10.1159/000178208

出版商:S. Karger AG    

年代:1994

数据来源: Karger

摘要:

A model was developed in albino hairless mice to study microcirculation and viability of dorsal distally based myocutaneous flaps. The efficacy of this model was tested in 120 mice by evaluating the effects of excessive crimping and tension attributed to Proximate or Signet staples or to simple or mattress nylon sutures. Microhemodynamics were assessed using computer-assisted intravital videomicroscopic and electro-optical methods. Volumetric rates of blood flow were calculated within terminal arterioles from measurements of internal diameter and mean centerline cellular velocity. The viability was determined on day 5 by measuring the areas of necrosis (mm2) along the cut edges of these flaps. In 80 mice, flaps were elevated and examined at 0 h and then again at 24 or 48 h. There were 40 mice in each of these disturbed groups. In a third group of 40 mice, flaps were raised at 0 h without videomicroscopic examination at 0, 24, or 48 h (undisturbed group). All flaps were stapled or sutured to the original donor site with one of the four methods of closure. The results of this study indicate that sutures produce the highest incidence of necrosis at 5 days when compared to staples in the undisturbed groups of mice. However, no significant differences in necrosis were observed when flaps were disturbed at 48 h despite videomicroscopic evidence of depressed blood flow along their cut edges. In contrast, results at 24 h were equivocal and statistically not significant. These data suggest that the phenomenon of delay and/or flap recirculation following removal and reapproximation of sutures or staples drastically improves perfusion and viability of disturbed flaps. It is also concluded that the homozygous hairless mouse model presents reliable vascular anatomy and that flap survival lengths can consistently be reproduced experimentally. Since color and hair distribution are similar to those of human skin and simulate the surgical flaps utilized clinically, the albino hairless mouse flap is judged to be a valuable model for investigating microvascular function and flap viability in response to surgical and mechanical factors.

ISSN:0167-6865    

DOI:10.1159/000178209

出版商:S. Karger AG    

年代:1994

数据来源: Karger

ISSN:0167-6865    

DOI:10.1159/000178210

出版商:S. Karger AG    

年代:1994

数据来源: Karger

ISSN:0167-6865    

DOI:10.1159/000178211

出版商:S. Karger AG    

年代:1994

数据来源: Karger

摘要:

RJH Dutrochet (1776-1847) may be remembered for his discovery of osmosis in 1826. This essay explores the meanings of that discovery within the science of the early nineteenth century, including contemporary ideas on plant and animal microstructure and on physical explanations for the phenomena of life. Dutrochet is revealed as a ‘romantic’ exponent of’organic phy

ISSN:0167-6865    

DOI:10.1159/000178212

出版商:S. Karger AG    

年代:1994

数据来源: Karger

ISSN:0167-6865    

DOI:10.1159/000178213

出版商:S. Karger AG    

年代:1994

数据来源: Karger

ISSN:0167-6865    

DOI:10.1159/000178214

出版商:S. Karger AG    

年代:1994

数据来源: Karger

ISSN:0167-6865    

DOI:10.1159/000178215

出版商:S. Karger AG    

年代:1994

数据来源: Karger

ISSN:0167-6865    

DOI:10.1159/000178216

出版商:S. Karger AG    

年代:1994

数据来源: Karger

ISSN:0167-6865    

DOI:10.1159/000178217

出版商:S. Karger AG    

年代:1994

数据来源: Karger