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41.
Robert M. Russell M.D. 《Nutrition reviews》1992,50(12):463-466
42.
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
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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
46.
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
47.
SF 36 health survey questionnaire: II. Responsiveness to changes in health status in four common clinical conditions. 总被引:6,自引:0,他引:6
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OBJECTIVE--To assess the responsiveness of the SF 36 health survey questionnaire to changes in health status over time for four common clinical conditions. DESIGN--Postal questionnaires at baseline and after one year's follow up, with two reminders at two week intervals if necessary. SETTING--Clinics and four training general practices in Grampian region in the north east of Scotland. PATIENTS--More than 1,700 patients aged 16 to 86 years with one of four conditions: low back pain, menorrhagia, suspected peptic ulcer, and varicose veins; and a random sample of 900 members of the local general population for comparison. MAIN MEASURES--A transition question measuring change in health and the eight scales of the SF 36 health survey questionnaire; standardised response means (mean change in score for a scale divided by the standard deviation of the change in scores) used to quantify the instrument's responsiveness to changes in perceived health status, and comparison of patient scores at baseline and follow up with those of the general population. RESULTS--The response rate exceeded 75% in a patient population. Changes across the SF 36 questionnaire were associated with self reported changes in health, as measured by the transition question. The questionnaire showed significant improvements in health status for all four clinical conditions, whether in referred or non-referred patients. For patients with suspected peptic ulcer and varicose veins the SF 36 profiles at one year approximate to the general population. CONCLUSIONS--These results provide the first evidence of the responsiveness of the SF 36 questionnaire to changes in perceived health status in a patient population in the United Kingdom. 相似文献
48.
Sheana Salyers Bull Cynthia Gillette Russell E Glasgow Paul Estabrooks 《Health education & behavior》2003,30(5):537-549
Information on external validity of work site health promotion research is essential to translate research findings to practice. The authors provide a literature review of work site health behavior interventions. Using the RE-AIM framework, they summarize characteristics and results of these studies to document reporting of intervention reach, adoption, implementation, and maintenance. The authors reviewed a total of 24 publications from 11 leading health behavior journals. They found that participation rates among eligible employees were reported in 87.5% of studies; only 25% of studies reported on intervention adoption. Data on characteristics of participants versus nonparticipants were reported in fewer than 10% of studies. Implementation data were reported in 12.5% of the studies. Only 8% of studies reported any type of maintenance data. Stronger emphasis is needed on representativeness of employees, work site settings studied, and longer term results. Examples of how this can be done are provided. 相似文献
49.
Factors affecting conjugative transfer of plasmid pWG613, determining gentamicin resistance, in Staphylococcus aureus 总被引:2,自引:0,他引:2
Factors that are known to influence plasmid transfer in bacterial populations were studied for the conjugative plasmid pWG613, which determined gentamicin resistance in Staphylococcus aureus. The transfer frequency was largely unaffected over a wide range of temperature (18-42 degrees C); pH also had little effect on the transfer frequency in the range 5.0-8.5. High cell density and log phase cultures were required for optimal plasmid transfer, as were donor:recipient ratios of 0.003-3.3. 相似文献
50.
Complications associated with maxillary nerve block anaesthesia via the greater palatine canal 总被引:2,自引:0,他引:2
Anthony M. Sved John D. Wong Head Peter Donkor James Horan Leesa Rix Justin Curtin and Russell Vickers 《Australian dental journal》1992,37(5):340-345
This paper documents the type, frequency and duration of complications associated with regional anaesthesia of the maxillary nerve via the greater palatine canal in a series of 101 patients treated in the Oral Surgery Department, United Dental Hospital of Sydney. 相似文献