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101.
J. Byrne MB BCh FRCSI J. W. Hallett Jr. MD C. F. Kollmorgen MD M. M. Gayari BS W. Davies MD FRCSC 《Annals of vascular surgery》1996,10(2):156-165
Our aim was to examine the feasibility of a totally laparoscopic insertion of a bifurcated aortofemoral bypass graft in a canine model and to compare the surgical results with those in control animals undergoing standard grafting and laparoscopic-assisted bypass procedures. Using a six-port approach, we exposed and cross clamped the aorta, tunneled a bifurcated Dacron graft, and performed an end-to-end aortic anastomosis while maintaining pneumoperitoneum by means of CO2. Proximal anastomoses were performed with 4/0 double-ended continuous Prolene sutures and distal anastomoses were performed through standard groin incisions. Total operating and aortic cross-clamp times were measured as was the total blood loss for each procedure. Clinical outcome was also documented. Eight female laboratory-bred hounds underwent successful totally laparoscopic aortobifemoral bypass grafting, eight underwent open grafting, and eight underwent laparoscopic-assisted bypass. Mean operating time was 193 minutes in the animals undergoing totally laparoscopic insertion vs. 156 minutes in the open group and 180 minutes in the laparoscopic-assisted group. Aortic cross-clamping time was also significantly longer at 87 minutes vs. 43 minutes (p < 0.001)=" in=" the=" totally=" laparoscopic=" group,=" but=" blood=" loss=" was=" less.=" all=" eight=" laparotomy=" and=" laparoscopic-assisted=" dogs=" were=" still=" alive=" with=" no=" complications=" at=" 28=" days,=" whereas=" three=" of=" the=" eight=" in=" the=" totally=" laparoscopic=" group=" showed=" evidence=" of=" temporary=" paraplegia.=" this=" experimental=" study=" demonstrates=" that=" a=" totally=" laparoscopic=" approach=" can=" be=" used=" to=" insert=" a=" bifurcated=" aortofemoral=" bypass=" with=" a=" proximal=" end-to-end=" anastomosis=" but=" currently=" does=" not=" save=" time=" and=" may=" increase=" the=" risk=" of=" neurologic=">Presented at the Twentieth Annual Meeting of the Peripheral Vascular Surgery Society, New Orleans, La., June 10, 1995. 相似文献
102.
Biological reaction to carbon fiber implants: the formation and structure of a carbon-induced "neotendon" 总被引:3,自引:0,他引:3
I W Foster Z A Rális B McKibbin D H Jenkins 《Clinical orthopaedics and related research》1978,(131):299-307
In 43 young rabbits, the tendo Achilles and flexor digitorum longus tendon were excised and replaced by filamentous carbon fiber. Tendo-Achilles in controls was repaired by silk or nylon sutures or left without replacement. Concurrent excision of the posterior tibial nerve was performed in one group of the carbon-replacing tendo-Achilles operations. When fully functioning, carbon-induced "neotendon" rapidly developed from young fibroblastic tissue outgrowths of the loose mesenchymal tissue of the perineurium and adventitia of the blood vessels in the adjacent neurovascular bundle. Silk or nylon replacement of the excised Achilles tendon did not lead to successful production of a new substitute. Carbon fibers were unsatisfactory for replacement implants for the flexor digitorum longus tendons. 相似文献
103.
The continued growth of hospital and clinical pharmacy should be paralleled by the development of sound research methods justifying innovative practices. Such research will, on occasion, require experimentation involving human subjects. The principal means of assuring that the welfare of research participants is not compromised is through the procurement of effective informed consent. Pharmacists, like many other health professionals, have had relatively little exposure to methodology involved in the writing of an informed consent instrument. A comprehensive document must not only conform to the requirements of federal regulatory agencies, but must also satisfy various institutional guidelines. Past instances of unethical human experimentation are discussed, and a format for preparation of an informed consent instrument is examined. Circumstances requiring informed consent and identification of the basic elements of consent are also explained. 相似文献
104.
105.
We report the unusual case of a 43-year-old woman who presented with Romberg's progressive facial hemiatrophy and spontaneous scleral perforation in the ipsilateral eye, for which scleral grafting was performed. Histologic and ultrastructural examination of the scleral specimen revealed a noninflammatory lytic process. The location of the scleral loss, exactly on the line of the "en coup de sabre" atrophy, as well as the light microscopy and ultrastructural histopathologic findings suggest that the scleral destruction was a late manifestation of Romberg's disease. 相似文献
106.
107.
A new method is described for recording the emotion-induced decrease in skin resistance area, which is known as the skin-resistance response (SRR). The method employs a simple current source and a new type of tetrapolar electrode in which the SRR is measured with the non-current-carrying electrodes. The signal produced can be recorded with a standard electrocardiograph. Typical SRRs from two subjects are presented. 相似文献
108.
The effects of aging on the responsiveness of hippocampal neurons to iontophoretic application of L-glutamate and AMPA were studied in vitro. There were no effects of age on neuronal responses to L-glutamate; however, CA1 pyramidal cells of old rats, but not granule cells in the fascia dentata, showed both a smaller reduction in extracellularly-recorded synaptic responses following application of AMPA (presumably mediated by depolarization), and smaller extracellular "DC" fields (measured by subtracting the DC potentials at the dendrite and soma following AMPA application in the dendrites). To examine the cellular bases of this age-related alteration in AMPA sensitivity, two additional electrophysiological approaches were used: (1) measurement of the amplitude ratios of extracellular EPSP and fiber potential components of the Schaffer collateral-CA1 response; (2) measurement of intracellularly recorded unitary EPSPs and quantal analysis of their fluctuations. The interpretations that would be placed on four hypothetical possible outcomes of such experiments are outlined and assessed in relation to the experimental data. The pattern of results obtained in the present experiments supports the following conclusions: In old rats, individual Schaffer collateral synapses do not appear to have altered AMPA receptor properties, as neither the mean size of the unitary synaptic response nor the apparent quantal size differs between age groups; however, the data do support the conclusion that there are fewer synapses per Schaffer collateral branch in old versus young CA1 pyramidal cells. 相似文献
109.
The Colorado Client Assessment Record (CCAR) is a problem checklist and level of functioning rating instrument used to describe admission to a public mental health system. A brief, non-technical summary of recent research and administrative applications involving this instrument is presented. A stable factor structure, generalizable to several diverse client populations, is reported. Scaling procedures for measuring these procedures and a client typology based on this scaling are described. The client typology is differentially related to the types of services received and the costs of treatment episodes. The typology is also used to understand differences in case mixes and lengths of stay at two state hospitals. 相似文献
110.
Frydenberg HB 《Obesity surgery》1991,1(3):315-317
Many forms of gastric banding have been described and high reoperation rates reported. These can be mainly attributed to excess
vomiting associated both with and without stenosis. Reflux oesophagitis and the ‘sump’ effect may be other causes. This paper
examines the problems associated with banding leading to revisional surgery and introduces a new technique, ‘fundal supporting
suture’, to correct these problems. Preliminary results on 126 bandings without the modification and 22 with the modification
are presented. 相似文献