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991.
Sandoval JA Lou D Engum SA Fisher LM Bouchard CM Davis MM Grosfeld JL 《Journal of pediatric surgery》2006,41(3):518-523
Background
Diaphragmatic reconstruction remains a challenging problem. There is limited information concerning the use of small intestinal submucosa (SIS) in congenital diaphragmatic hernia repair. A canine model was used to evaluate the use of a SIS patch in diaphragmatic reconstruction.Methods
Eleven beagle puppies (1.6-4.2 kg, 8 weeks old) underwent left subcostal laparotomy, central left hemidiaphragm excision (2 × 7 cm, 50% loss), and reconstruction with a 4-ply group I (n = 5) or 8-ply group II (n = 6) SIS patch. Chest radiographs were taken at time of operation and 3 and 6 months postoperatively. Animals were killed at 6 months. Adhesion formation (both pleural and abdominal), gross visual evaluation of the patch, and histology were compared.Results
In group I (4-ply), 1 animal died at 3 months from patch deterioration accompanied by stomach herniation that resulted in respiratory failure. In the 4 remaining animals, chest radiographs showed no evidence of herniation or eventration. On physical examination, there was no evidence of chest wall deformity. During gross surgical examination, the 4-ply patches showed thinning, multiple defects, and liver herniation in 3 animals. In 1 pup, the patch was thickened, intact, well incorporated at the repair site, and adherent to the liver and spleen. In group II (8-ply), 1 animal died of cardiopulmonary failure in the early postoperative period. In the other 5 animals, chest radiographs showed evidence of eventration in 1. On gross examination the patch adhered to the liver in all 5 surviving animals. In 4, the patches were thickened, viable, but had some shrinkage. One patch pulled away from the native diaphragm laterally; however, no visceral herniation was present. In the 1 animal with eventration, there was no evidence of a patch. Adhesion scores (AS) were graded and determined by the sum of extent (0-4), type (0-4), and tenacity (0-3). Average abdominal AS in group I was 5.6 ± 0.8 vs 10.2 ± 0.2 (P = .079) for group II. Average lung AS was 0.6 ± 0.6 in group I vs 3.8 ± 1.1 (P = .0476) for group II. Histological examination showed group II patches had greater collagen deposition with central calcification and mild inflammation within the residual graft, whereas group I patches were much thinner and were composed of granulation tissue without evidence of residual graft.Conclusions
These data indicate that 8-ply SIS repair of diaphragmatic defects was superior (80%; 4/5 to 4-ply, 20%; 1/5, success). Organ adherence appears to be necessary for neovascularization of the SIS composite. Eight-ply grafts appear to be more durable and persist for a longer period, which may improve neovascularization. Long-term follow-up to evaluate remodeling characteristics of the patch material is required. 相似文献992.
993.
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995.
M A Lou A K Mandal J L Alexander H Thadepalli 《Archives of surgery (Chicago, Ill. : 1960)》1977,112(8):965-967
Using the modern anaerobic transport media and meticulous culture techniques, 74 patients undergoing biliary tract surgery were studied. The biliary system was found to be sterile in 58 patients (78%). Fifteen patients had 35 isolates of aerobic and facultative bacteria. The most common ones were Klebsiella, Enterococcus, and Escherichia coli. The only anaerobe isolated was Clostridium perfringens. Eight of 17 patients (47%) with acute cholecystitis and five of 49 patients (10%) with chronic cholecystitis, harbored bacteria in the biliary system. This study suggests that anaerobes are rare in the human biliary system; therefore, if antibiotic therapy is considered, aerobic coverage should suffice. 相似文献
996.
Summary Young adult cynomolgus monkeys are susceptible to infection from Coxsackie A type 16 virus following parenteral inoculation. After infection monkeys may develop fever and neuromuscular disability associated with extensive injury to neurones of the spinal cord and brain stem. Focal myositis developed in 2 monkeys. Monkeys may develop measurable viremia; Coxsackie A 16 virus was not recovered from CNS or other tissues. Following infection type specific antibodies develop. Cutaneous lesions were not found.Aided by grants from the National Foundation and from the United States Public Health Service.We are indebted to Dr.C. R. Robinson, University of Toronto, Toronto, Ontario, for sending us this strain of A 16 virus. 相似文献
997.
998.
A three-generation transmission of under five percentile values for serum low density lipoprotein and low density lipoprotein cholesterol typical of heterozygous familial hypobetalipoproteinemia was demonstrated in a Danish family. Slight clinical signs of CNS abnormality were found in 4 of the 8 subjects with heterozygous familial hypobetalipoproteinemia, but did not resemble the neurological findings in abetalipoproteinemia nor in the previously described patients with familial hypobetalipoproteinemia. There were no signs of myelin dysfunction in the central nervous system as judged from the normal latency of visual and somatosensory evoked potentials. 相似文献
999.
Thomas B. Shea Mary Lou Beermann Feng-Song Wang 《Molecular and chemical neuropathology / sponsored by the International Society for Neurochemistry and the World Federation of Neurology and research groups on neurochemistry and cerebrospinal fluid》1995,24(2-3):203-219
Previous studies have demonstrated the appearance of phosphorylated neurofilament (NF) subunits within perikaryal cytoskeletons following aluminum exposure. In order to examine the mechanisms leading to this altered distribution of NF subunits, we carried out biochemical analyses of NF subunits in Triton-insoluble and-soluble fractions derived from aluminum-treated NB2a/d1 cells. In addition to increases in the Triton-insoluble cytoskeleton, increases in all three NF subunits were also detected within the Triton-soluble fraction of aluminum-treated cells. To address the nature of this increase in Triton-soluble subunits, aluminum-treated and untreated cultures were harvested in the absence of Triton and fractionated by established procedures to yield fractions greatly enriched for perikarya and neurites, respectively. Each of these subcellular fractions was then subjected to further homogenization in the presence of 1% Triton and centrifugation to yield Triton-insoluble cytoskeletons and Triton-soluble material derived from perikarya and axonal neurites, respectively. Resulting Triton-soluble fractions were “clarified” by high-speed centrifugation to eliminate oligomeric assemblies or soluble neurofilaments. Immunoblot analysis demonstrated quantitative recovery of the aluminum-induced increase in Triton-soluble NF subunits in the perikaryal fraction. Additional aluminum-treated and untreated cultures were pulse-chase radiolabeled with [35S]methionine and fractionated into Triton-insoluble and soluble fractions from isolated perikarya and axonal neurites. Autoradiographic analysis of immunoprecipitated NF subunits revealed that aluminum treatment delayed the translocation of newly synthesized subunits into neurites and resulted in the accumulation of radiolabeled subunits within the Triton-soluble fraction of perikarya. These findings suggest that aluminum may exert a relatively greater effect on NF subunits that have not yet undergone axonal transport and/or incorporation into Triton-insoluble structures vs those that have already deposited into axons. This possibility was supported by the observation that a higher concentration of aluminum was required to alter the electrophoretic migration of in vitro reassembled neurofilaments vs that required for unassembled NF subunits. These findings provide possible mechanisms for the accumulation of NF subunits in perikarya during aluminum intoxication. 相似文献
1000.
间质性肺疾病血清前胶原Ⅲ的初步研究 总被引:1,自引:0,他引:1
本文检测了26例间质性肺疾病病人和11例正常对照组血清Ⅲ型前胶原含量。结果表明,ILD病人PCⅢ含量显著高于对照组;认为血清PCⅢ水平的改变可能作为话估肺内胶原代谢的一个指标。 相似文献