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51.
Christopher D Wells Russell I Heigh Virender K Sharma Michael D Crowell Suryakanth R Gurudu Jonathan A Leighton Nora Mattek David E Fleischer 《BMC gastroenterology》2007,7(1):19
Background
Many factors impacting cecal intubation rates have been examined in detail; however, little information exists regarding the effect of the timing of the procedure. We sought to examine any difference in cecal intubation rates between morning and afternoon colonoscopies and identify factors contributing to a discrepancy. 相似文献52.
Michael Lefevre Author Vitae Penny M. Kris-EthertonAuthor Vitae Guixiang ZhaoAuthor Vitae Russell P. TracyAuthor Vitae 《Journal of the American Dietetic Association》2004,104(3):410-419
The cause of many myocardial infarctions is occlusive thrombosis, or a blood clot that stops blood flow in a coronary artery. Hemostasis involves a complex system of factors, which normally form and degrade blood clots, that work within a delicate balance. Emerging evidence suggests that some hemostatic factors, including factor VII, fibrinogen, and plasminogen activator inhibitor-1, are associated with increased risk for cardiovascular disease (CVD). Accumulating evidence suggests a relationship between dietary fatty acids and emerging hemostatic CVD risk factors, although much of this evidence is incomplete or conflicting. Dietary supplementation with marine n-3 fatty acids prolongs bleeding time and may decrease risk for thrombosis. Factor VII coagulant activity modestly decreases with reductions in saturated fatty acid (SFA) intake and thereby may contribute to the beneficial effects of low SFA diets. Large triglyceride-rich particles formed during postprandial lipemia can support the assembly and function of coagulation complexes and seem to play a role in the activation of factor VII, and thus may partially explain increased CVD risk associated with increased postprandial triglyceridemia. As our understanding of the role of dietary fatty acids and hemostasis evolves, it is likely that we will be able to make specific dietary recommendations to further decrease CVD risk. At this juncture, however, increasing marine n-3 fatty acids and decreasing certain SFAs are leading strategies to reduce hemostatic CVD risk factors. An array of dietary strategies that target multiple CVD risk factors could have a greater impact on CVD than a single risk factor intervention strategy. 相似文献
53.
Robert M. Russell M.D. 《Nutrition reviews》1992,50(12):463-466
54.
This study evaluates the microvascular reperfusion of ischemic skin flaps with and without acute hyperbaric oxygen (HBO) treatment. Thirty-two axial pattern epigastric skin flaps (3 x 6 cm) in male Wistar rats were subjected to 8 hours of global ischemia by pedicle clamp occlusion. The rats were divided into the following control and two experimental groups: Control (n = 12) with ischemia, no HBO; Group 1 (n = 11) with HBO treatment (three 1.75-hour dives, 2.5 absolute atm, 100% O2) during ischemia; and Group 2 (n = 9) with HBO treatment (two 1.75-hour dives) immediately after ischemia. Laser Doppler flows were recorded in two distal standardized flap locations at 0.5, 2, 4, and 18 hours after reperfusion in control rats and Group 1 rats and at 18 hours only in Group 2 rats, using a Med-Pacific 6000 laser Doppler unit. Mean distal flap laser Doppler flows (mV) were Control: 0.5 hours = 23.2 +/- 11.9, 2 hours = 52.8 +/- 27.3, 4 hours = 53.6 +/- 32.1, 18 hours = 40.2 +/- 36.2; Group 1: 0.5 hours = 71.8 +/- 30.9 (p less than 0.05 vs. control), 2 hours = 74.3 +/- 27.3, 4 hours = 67.4 +/- 20.6, 18 hours = 79.1 +/- 40.3 (p less than 0.05 vs. control); and Group 2: 18 hours = 90.3 +/- 47.9 (p less than 0.05 vs. control). It is concluded that acute HBO treatment of ischemic rat skin flaps improves distal microvascular perfusion as measured by laser Doppler flowmetry. This effect is observed for HBO treatment given either during or immediately after prolonged global ischemia.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
55.
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57.
We have determined the frequency of heterozygosity of the short arm of chromosome 17 in 20 cervical tumours using the highly polymorphic probe pYNZ22. Only 25% of the tumours were heterozygous at this locus. This is significantly lower than the level of 86% heterozygosity for this locus in the general population indicating that loss of one allele occurs in cervical cancer. Heterozygosity for a locus on the long arm of the same chromosome showed no significant difference between the tumours and the general population indicating that genetic loss was confined to the short arm of the chromosome. The analysis of premalignant lesions showed 70% of patients were heterozygous suggesting that loss of material from the short arm of chromosome 17 took place at a late stage in tumour development. This report confirms predictions made from previous karyotypic analysis and is the first indication of allele loss on the short arm of chromosome 17 in cervical cancer. 相似文献
58.
F M Muggia E LePoidevin S Jeffers C Russell W Boswell C P Morrow J Curtin J Schlaerth 《Annals of oncology》1992,3(2):149-154
Nineteen patients with ovarian cancer and minimal residual or persistent disease who were treated with cisplatin or carboplatin-based intraperitoneal (IP) regimens had distribution studies of IP contrast and computerized tomography prior to and during treatment. The distribution pattern was assessed retrospectively and scored for the presence of contrast in each of eight regions: the under surface of right and left diaphragms, the right and left paracolic gutters, the lesser omental sac, the intramesenteric region and the true and false pelvis. Assigning a point to each region with adequate distribution, we classified 10 patients to an excellent pattern (greater than or equal to 7 of 8 regions), 6 to a good pattern (5 to less than 7 regions), and 3 to an inadequate distribution pattern (less than 5 regions). Serial studies were performed in 8 patients after more than 4 cycles of IP therapy. In these patients, all of whom were tolerating treatment without progression, the distribution remained virtually unchanged for those with excellent distribution. One of three with good distribution manifested inadequate distribution on repeat study, and one of two with inadequate distribution improved to show a good pattern. In this small study there was no correlation of distribution patterns with plasma CA-125 at onset of IP treatment and prior surgical procedures or placement of the catheter tip. However, three patients with unsatisfactory patterns had procedures consisting of catheter placement only rather than formal reassessment laparotomies for ovarian cancer. Since satisfactory IP distribution may be required for obtaining a therapeutic advantage from IP therapy, methods for its assessment must be developed.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
59.
Diagnostic tests for Helicobacter pylori: comparison and influence of non-steroidal anti-inflammatory drugs.
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A. S. Taha P. Boothman I. Nakshabendi J. Reid C. Morran C. G. Gemmell F. D. Lee R. D. Sturrock R. I. Russell 《Journal of clinical pathology》1992,45(8):709-712
AIMS: To evaluate the efficacy of culture, histology, CLO-test, Helico-G and Pyloriset tests in diagnosing Helicobacter pylori in the presence or absence of non-steroidal anti-inflammatory drugs (NSAIDs). METHODS: Of 134 patients studied, 75 had taken NSAIDs. At endoscopy, biopsy specimens were taken for culture, histology, and CLO-test. Blood was also taken for enzyme linked immunosorbent assay (ELISA) (Helico-G) and latex agglutination (Pyloriset) tests. RESULTS: The sensitivity, specificity, and predictive values of histology and CLO-test, compared with culture, ranged from 90% to 97%, regardless of NSAID intake. In the 59 patients not taking NSAIDs Helico-G had a sensitivity of 75% (p < 0.05) and a specificity of 61%; Pyloriset's sensitivity and specificity were, respectively, 63% (p < 0.05) and 67%. In the 75 patients taking NSAIDs the sensitivity of Helico-G was 81% and its specificity 45% (p < 0.05); Pyloriset had a sensitivity of 61% (p < 0.05) and a specificity of 50% (p < 0.05). CONCLUSION: These findings suggest that H pylori is more reliably diagnosed by culture, histology, and CLO-test than by the serological tests used in this study, especially in patients treated with NSAIDs. 相似文献
60.
Background : Wounds are a common problem, particularly in the elderly population. The scale of wound problems in hospital is largely unknown because wounds are widely dispersed. The present study examined the point prevalence of hospital wounds and undertook a pressure ulcer risk assessment of all patients on one day. Methods : All 360 inpatients were surveyed and thoroughly examined. A risk scale for pressure sore development, the Norton score, was applied. When wounds were found, information was collected to determine their aetiology. Results : Forty leg ulcers, 40 pressure sores, 85 surgical wounds and seven other types of wounds were found. Most leg ulcer and pressure sore cases were admitted for other reasons. The Norton score did not predict all cases of pressure ulceration. A total of 52% of wounds did not qualify for additional funding under current funding criteria. Conclusion : The prevalence of non-surgical wounds in Heidelberg Repatriation Hospital was easily underestimated. Wound care management can be optimized by staff education and protocol design, early identification of troublesome wounds and of at-risk patients, and a cross-sectional approach that incorporates wound-management teams. 相似文献