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81.
Lethal and mutagenic effects of tritium incorporated into position 8 of the purines in phage lambda DNA and the role of the Fpg protein 总被引:1,自引:0,他引:1
Physicians and patients have been frustrated by the lack of reliable information on unconventional therapies. To help fill this gap in the area of breast cancer therapy, the Canadian Breast Cancer Research Initiative formed a task force to advise it on how best to promote research into unconventional therapies. As part of the work of the task force, a review of the available literature was carried out for each of the following products: Essiac, green tea, Iscador, hydrazine sulfate, vitamins A, C and E, and 714-X. The first article in this series on unconventional therapies for cancer describes the methodology used to obtain and evaluate the information and provides a summary of the findings on Essiac. Subsequent articles will cover the other products. For most of the products reviewed, there has been some indication of possible benefit but no definitive evidence. Innovative and collaborative research needed to meet the information needs of growing numbers of patients and their physicians is now being sponsored by the Canadian Breast Cancer Research Initiative. Open communication between patients and physicians is also necessary for the maintenance of an appropriate therapeutic partnership and for the identification and control of side effects. The Ontario Division of the Canadian Cancer Society, a partner in the Canadian Breast Cancer Research Initiative, supported the preparation of a patient-information piece on unconventional therapies to accompany the series. This item will assist patients who are considering such therapies and will promote open communication between patients and their physicians. 相似文献
82.
VL Ng R Valdes-Camin EL Gottfried SA Echaves AG Stead RF Ebert 《Canadian Metallurgical Quarterly》1998,109(3):338-346
OBJECTIVE: Severe obesity (ie, at least 100% overweight or body mass index > or =40 kg/m2) is associated with significant morbidity and increased mortality. It is apparently becoming more common in this country. Conventional weight-loss treatments are usually ineffective for severe obesity and bariatric surgery is recommended as a treatment option. However, longitudinal data on the long-term outcome of bariatric surgery are sparse. Available data indicate that the outcome of bariatric surgery, although usually favorable in the short term, is variable and weight regain sometimes occurs at 2 years after surgery. The objective of this study is to present a review of the outcome of bariatric surgery in three areas: weight loss and improvement in health status, changes in eating behavior, and psychosocial adjustment. The study will also review how eating behavior, energy metabolism, and psychosocial functioning may affect the outcome of bariatric surgery. Suggestions for additional research in these areas are made. METHOD: Literature review. RESULTS: On average, most patients lose 60% of excess weight after gastric bypass and 40% after vertical banded gastroplasty. In about 30% of patients, weight regain occurs at 18 months to 2 years after surgery. Binge eating behavior, which is common among the morbidly obese, may recur after surgery and is associated with weight regain. Energy metabolism may affect the outcome of bariatric surgery, but it has not been systematically studied in this population. Presurgery psychosocial functioning does not seem to affect the outcome of surgery, and psychosocial outcome is generally encouraging over the short term, but there are reports of poor adjustment after weight loss, including alcohol abuse and suicide. CONCLUSIONS: Factors leading to poor outcome of bariatric surgery, such as binge eating and lowered energy metabolism, should be studied to improve patient selection and outcome. Long-term outcome data on psychosocial functioning are lacking. Longitudinal studies to examine the long-term outcome of bariatric surgery and the prognostic indicators are needed. 相似文献
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VS Alekseeva TA Karaseva VL Na?din NA Shtamberg 《Canadian Metallurgical Quarterly》1977,77(9):1329-1333
The report contains data concerning occupational and social rehabilitation of 46 patients operated on for aneurysma of the anterior communicative artery. It was established that the occupational prognosis depends upon the severity of the hemmorhage, character of surgical operation. Of significance are the conditions of work, time after the surgical operation. The authors mark that in 2/3 of the operated on patients the working capacity is being restored. A spontaneous restoration of diaturbed functions is slow and is not always sufficient. With this purpose it is expedient to repeat courses of a general tonic and special rehabilitative therapy. A favourable factor in the readaptation of patients is their early engagement in working activities. The authors give their recommendations for medical labour expert testimony for this category of patients. 相似文献
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The influence of hepatocyte enlargement on intrahepatic hemodynamics was assessed in the isolated perfused rat liver preparation (IPRL) using two experimental models: hypotonic liver cell swelling and phenobarbitone-induced hepatocyte hypertrophy. The analysis of pressure-flow data obtained from the portal vascular bed over a flow range of 0 to 70 mL/min in the presence of a maximally-effective concentration of the vasodilator agent papaverine hydrochloride (6 x 10(-4) mol/L) enabled the calculation of P0, an estimate of the pressure required to passively distend the intrahepatic vasculature, and Gmax, the maximal portal vascular conductance. By comparison with an isotonic perfusion medium (Krebs-Henseleit buffer [KH] containing 2.5% bovine serum albumin [BSA]), perfusion with a hypotonic medium induced a significant increase in mean hepatocyte cross-sectional area (H(A)) (590 +/- 21 vs. 324 +/- 23 microm(-2), p < .05), a fall in Gmax (0.39 +/- 0.08 vs. 2.02 +/- 0.18 mL/min/g/mm hg, P < .001), and an increase in P0 (2.96 +/- 0.38 vs. 1.58 +/- 0.07 mm hg, P < .001). Phenobarbitone administered in drinking water (0.5 g/L) over a period of 60 days also induced a significant degree of hepatocyte enlargement (HA, 510 +/- 29 microm2, P < .05). On day 7, portal pressure measured in vivo in this group was significantly elevated compared with untreated controls (10.5 +/- 0.3 vs. 8.4 +/- 0.2 mm hg, P < .001), while in the IPRL Gmax was reduced (0.48 +/- 0.01 mL/min/g/mm hg, P < .001), and P0 was increased (2.23 +/- 0.17 mm hg, P < .05). However, with continued phenobarbitone treatment portal pressure, Gmax and P0 returned toward control values. The results confirm that hepatocyte enlargement is associated with a significant disturbance of intrahepatic hemodynamics but also that some adaptation occurs if hepatocyte enlargement is sustained over a prolonged period of time. 相似文献
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EA Galati VL Nunes ME Dorval ET Oshiro G Cristaldo MA Espíndola HC da Rocha WB Garcia 《Canadian Metallurgical Quarterly》1996,30(2):115-128
Interleukin-1 beta (IL-1 beta) significantly inhibits insulin secretion from glucose stimulated islet cells. The mechanism for this inhibition has been hypothesized to be due to stimulation of the inducible form of nitric oxide synthase and a resulting increase in nitric oxide (NO) concentration. Ways to block the effect of IL-1 beta have focused on blocking the binding of IL-1 beta to the IL-1 receptor and the use of antioxidants to neutralize increases in NO. This report focuses on a 33 residue peptide synthesized based on the C-terminal region of the IL-1 beta molecule, a reported binding site of the IL-1 beta molecule, and the redoxcycling antioxidant pyrroloquinoline quinone (PQQ). The 33 residue peptide did not function as an antagonist, but as a weak agonist. High concentrations of PQQ itself inhibited glucose-dependent insulin release while low concentrations did not. PQQ had no effect on the actions of IL-1 beta. Three isosteric and isomeric analogues of PQQ were also investigated. One of the PQQ isomers had an inhibitory effect on insulin secretion at low concentrations where PQQ had no effect. These results reflect the sensitivity of islets to oxidative stress. 相似文献