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31.
Wound healing response in surgical patients: recent food intake is more important than nutritional status 总被引:4,自引:0,他引:4
We have recently found that an impairment of the wound healing response (WHR) occurs in surgical patients with protein-energy malnutrition before there are any measurable changes in body fat and protein stores. The hypothesis of this study was that the patients' recent food intake is more important in determining the WHR than the patients' overall nutritional status. We have measured the recent food intake (by dietary recall), the WHR (by hydroxyproline accumulation in subcutaneous GORE-TEX implants), the pre-operative weight loss (per cent), and body fat and protein stores (by in vivo neutron activation analysis) in 83 patients awaiting a major elective gastrointestinal resection, and divided them into two groups: adequate recent food intake (n = 59) and inadequate recent food intake (n = 24). There was no significant difference between these two groups for age, sex, diagnosis, surgical procedure, weight loss (per cent), or the amount of body fat and protein stores but there was a significant difference in the WHR (1.81 +/- 0.16 s.e.m. versus 1.04 +/- 0.22 s.e.m. nmol hydroxyproline/mg GORE-TEX, P less than 0.005). These results show that pre-operative food intake has a greater influence over the wound healing response than absolute losses of protein and fat from body stores and they suggest that the maintenance of a normal food intake up until the time of surgery is of importance in preventing an impairment of the wound healing response. 相似文献
32.
Diana A. Lepore Kenneth R. Knight Surajit Bhattacharya Morris Ritz Sonia P. Robbins Peter Sieg Wayne A. Morrison Bernard McC. O'Brien 《Microsurgery》1994,15(10):685-692
The chief aim of this study was to maximize flap survival by counteracting the pathophysiological changes occurring during ischemia-reperfusion. Rabbit epigastric skin flaps given 21 hours of ischemia were infused intra-arterially with selected drugs at the start of reperfusion. Compared with control infused ischemic flaps, which had a 33% survival rate on day 7 post-ischemia, significant improvement was found with vasodilators nitrendipine (61%) and prostacyclin (65%) and the thrombolytic agent urokinase (65%); marginal improvement with the free radical scavenger desferrioxamine (53%); but no change with streptokinase (44%), heparin (21%), and ATP-MgCl2 (35%). A drug mixture comprising all of these agents except streptokinase and urokinase produced 87% survival, suggesting an additive effect. Biochemical assays on skin homogenates and blood implicated oxygen free radicals, neutrophil infiltration, and thromboxane in flap failure. These results imply that multiple factors are responsible for ischemic flap failure and that a mixture of drugs needs to be infused to counteract all of the detrimental changes. © 1994 Wiley-Liss, Inc. 相似文献
33.
J K Nayar J W Knight P E Kaiser J A Seawright S K Narang 《Journal of the American Mosquito Control Association》1992,8(1):61-64
Susceptibilities of natural populations of sibling species A, B and C of the Anopheles quadrimaculatus complex and the colonized strain A to subperiodic Brugia malayi and Brugia pahangi were compared. All 3 sibling species showed varying degrees of susceptibility to both B. pahangi and B. malayi, and they were considerably more susceptible to B. pahangi than to B. malayi. The rate and intensity of infection to B. pahangi were highest for species A (66.2% and 7.4 L3/female, respectively) and lowest for species B (21.3% and 1.7 L3/female). For B. malayi these values were higher for species A (29.7% and 1.84 L3/female) than for species B (13.3% and 0.86 L3/female) and C (12.6% and 0.75 L3/female). The colonized strain A of An. quadrimaculatus was significantly more susceptible to both Brugia species than the natural populations of sibling species A, B and C. 相似文献
34.
Leaves or infusions of feverfew, Tanacetum parthenium, have long been used as a folk remedy for fever, arthritis and migraine, and derived products are widely available in U.K. health food shops. Previous reports have suggested interactions with arachidonate metabolism. Crude chloroform extracts of fresh feverfew leaves (rich in sesquiterpene lactones) and of commercially available powdered leaves (lactone-free) produced dose-dependent inhibition of the generation of thromboxane B2 (TXB2) and leukotriene B4 (LTB4) by ionophore- and chemoattractant-stimulated rat peritoneal leukocytes and human polymorphonuclear leukocytes. Approximate IC50 values were in the range 5-50 micrograms/mL, and inhibition of TXB2 and LTB4 occurred in parallel. Isolated lactones (parthenolide, epoxyartemorin) treated with cysteine (to neutralize reactive alpha-methylene butyrolactone functions of the sesquiterpenes). Inhibition of eicosanoid generation appeared to be irreversible but not time-dependent. We conclude that feverfew contains a complex mixture of sesquiterpene lactone and non-sesquiterpene lactone inhibitors of eicosanoid synthesis of high potency, and that these biochemical actions may be relevant to the claimed therapeutic actions of the herb. 相似文献
35.
M C Hirst S J Knight M V Bell M Super K E Davies 《Clinical science (London, England : 1979)》1992,83(3):255-264
An amplification of a highly unstable DNA element has been identified at the fragile X locus in Xq27.3. This sequence appears to be both the source of the primary mutation causing the fragile X syndrome, apparently having its causative effect through the methylation of the FMR-1 HTF island and the region of cytogenetic fragility. The direct analysis of the genotype of carrier and affected individuals can be used as a direct diagnosis tool which will improve both the accuracy and speed of diagnosis. The identification of hereditary unstable DNA in a disease with such a wide level of non-penetrance and variable phenotype may give clues as to the basis of non-penetrance in other human genetic disorders. 相似文献
36.
37.
W. M. Gregory P. Smith M. A. Richards C. J. Twelves R. K. Knight R. D. Rubens 《British journal of cancer》1993,68(5):988-995
The outcome for 758 consecutive patients who had received one or more chemotherapy regimens for recurrent or metastatic breast cancer is presented. The response rate following first line treatment was 34%. Median duration of response was 7.8 months, median time to progression was 3.7 months and median survival was 7.9 months. The only factor predicting for response, of factors recorded at presentation and at initiation of chemotherapy, was the use of anthracycline based regimens, though this may reflect the patient selection policy. Initial disease free interval, presence of liver metastases and use of anthracyclines were significantly related to time to progression. Several factors related to survival following first chemotherapy, but anthracycline usage showed only a very weak correlation. One third of patients (249/758) received two or more chemotherapy regimens. The response rate (16%) and median time to progression (2.3 months) were significantly worse than for first line treatment. The outcome after third line chemotherapy was very similar to that observed following second line treatment. Achievement of an objective response with first line chemotherapy predicted for second response, but with insufficient power to be of use in selecting patients for subsequent chemotherapy. Time to progression following first line chemotherapy did not influence that after second line treatment. 相似文献
38.
Julian Knight 《Current infectious disease reports》2007,3(5):427-439
An increasing number of genetic association studies have implicated polymorphisms of cytokine genes as host genetic factors
influencing susceptibility to infectious disease, primarily using a candidate gene approach based on knowledge of disease
pathogenesis. The application and limitations of association studies are reviewed together with the impact of recent advances
in single nucleotide polymorphism mapping on strategic approaches to defining genetic susceptibility loci. It often remains
unclear whether associated genetic polymorphisms are themselves functionally relevant or acting only as markers within an
extended haplotype, and experimental approaches to investigating the functional impact of polymorphisms in noncoding regulatory
DNA sequences are discussed. An overview of genetic associations of cytokine genes with infectious disease is presented, together
with discussion of recent studies in a number of infectious diseases including hepatitis, HIV, malaria, and sepsis. 相似文献
39.
M. Al-lsmaily A. AI-Khussaiby I. G. Chestnutt K. W. Stephen A. AI-Riyami M. Abbas M. Knight 《Community dentistry and oral epidemiology》1996,24(5):362-363
Abstract This study reports the first ever national oral health survey of Omani 12-year-olds. Conducted in October 1993, of the 3,435 children examined, 1,438 (41.9%) were caries-free, although regional variations ranged from 24.8% to 61.9%. Overall, the national DMFT averaged 1.53, the majority of caries experienced being in the form of untreated decay, with occlusal surfaces of first permanent molars being the most commonly involved site. Oral hygiene was poor, only 11% of those examined being scored as plaque-free. 相似文献
40.
Jonathan C. Craig Les M. Irwig James Christie Albert Lam Ella Onikul John F. Knight Premala Sureshkumar L. Paul Roy 《Pediatric nephrology (Berlin, Germany)》1997,11(4):455-459
Variability in the interpretation of micturating cystourethrography by paediatric radiologists for the diagnosis of vesicoureteric
reflux in children was evaluated. All 265 micturating cystourethrograms (MCUs) that were available from 304 consecutive children
aged 0.5 – 61 months – who were investigated after their first urine infection between 1993 and 1995 as part of a prospective
cohort study – were selected for interpretation. Three experienced paediatric radiologists from the same department independently
interpreted the MCUs according to the grading system of the International Reflux Study in Children, from grades 0 to V, with
the presence of intrarenal reflux also noted. Apart from being informed that urine infection was the indication for the MCU,
no other clinical information was given to the radiologists. The indices of variability used were the percentage of agreement
and the kappa statistic, expressed as a percentage. Both measures were weighted with integers representing the number of categories
from perfect agreement. Disagreement was analysed for children and kidneys. For the diagnosis of vesicoureteric reflux in
individual patients, including grade, the percentage of agreement was 96% – 97% (kappa 90% – 91%) and the weighted percentage
of agreement was 96% – 98% (weighted kappa 93% – 94%). The same high level of agreement was present for individual kidneys,
with a percentage of agreement of 97% – 98% (kappa 89% – 92%) and a weighted percentage of agreement of 98% – 99% (kappa 94% – 95%).
There was near perfect agreement in the interpretation of radiological micturating cystourethrography among three experienced
paediatric radiologists for the diagnosis and grade of vesicoureteric reflux. Any variations in the medical care of children
suspected of having vesicoureteric reflux are not explained by differences in the reporting of this diagnostic test.
Received June 19, 1996; received in revised form November 1, 1996; accepted December 6, 1996 相似文献