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961.
962.
963.
BACKGROUND: Hypercholesterolemia is a major risk factor for coronary heart disease and nutrition management is the initial therapeutic approach. OBJECTIVE: This multicenter study evaluated the long-term effectiveness of psyllium husk fiber as an adjunct to diet in the treatment of persons with primary hypercholesterolemia. DESIGN: Men and women with hypercholesterolemia were recruited. After following an American Heart Association Step I diet for 8 wk (dietary adaptation phase), eligible subjects with serum LDL-cholesterol concentrations between 3.36 and 4.91 mmol/L were randomly assigned to receive either 5.1 g psyllium or a cellulose placebo twice daily for 26 wk while continuing diet therapy. RESULTS: Serum total and LDL-cholesterol concentrations were 4.7% and 6.7% lower in the psyllium group than in the placebo group after 24-26 wk (P < 0.001). Other outcome measures did not differ significantly between groups. CONCLUSIONS: Treatment with 5.1 g psyllium twice daily produces significant net reductions in serum total and LDL-cholesterol concentrations in men and women with primary hypercholesterolemia. Psyllium therapy is an effective adjunct to diet therapy and may provide an alternative to drug therapy for some patients.  相似文献   
964.
Objectives.Our aim was to study correlations between survival, disease recurrence, and p53 protein expression in a well defined population-based series of vulval squamous cell carcinoma and immediate adjacent epithelial skin changes.Methods.One hundred fifteen vulval squamous cell carcinoma were studied. Epithelial skin changes immediately adjacent to tumor were classified into nonneoplastic epithelial disorders (NNED) or vulval intraepithelial neoplasia (VIN). Archival specimens containing primary tumor and immediate adjacent skin were immunostained with a mouse monoclonal antibody to p53 protein.Results.p53 overexpression, defined as greater than 10% nuclear epithelial staining, was observed in 68% of tumors. Tumor immunostaining did not correlate with actuarial survival or disease-free interval. p53 overexpression was associated with a nonsignificant trend toward shorter disease-free interval in those tumors with nodal metastatic disease at diagnosis (P= 0.07). The only clinicopathological variable found to correlate with p53 expression was tumor grade (P= 0.002). Immediate adjacent abnormal skin changes were associated with p53 overexpression in 32% of cases. Adjacent normal skin did not immunostain for p53. p53 overexpression was most likely to occur in adjacent epithelial changes incorporating both NNED and high grade VIN (P= 0.005). Patterns of epithelial p53 overexpression in adjacent abnormal skin were either basal or full thickness. Full thickness epithelial p53 overexpression was most likely to occur in those disorders containing VIN (P< 0.0001). Positive immunostaining of adjacent skin abnormalities did not predict local tumor recurrence.Conclusions.This study demonstrates that although vulval squamous tumor p53 expression is not of prognostic significance, distinct immunostaining patterns can be observed in immediate adjacent skin. Vulval epithelial skin disorders displaying histological features of both NNED and VIN III may contain a profile of underlying molecular change which is of significance in subsequent tumor development.  相似文献   
965.
AIM—To evaluate the role of recombinant human erythropoietin (R-HuEpo) in reducing iron infusion, which may exacerbate free radical damage, leading to chronic lung disease.METHODS—A multicentre, randomised, placebo controlled, double blind study was carried out in four neonatal intensive care units in Yorkshire. Infants were randomly allocated and received either R-HuEpo (480 U/kg/wk) or placebo by twice weekly subcutaneous injection. The primary outcome measure was the number of days on respiratory support and a secondary outcome the number of blood transfusions required.RESULTS—Forty two very low birthweight (VLBW) infants were randomly allocated. There was little difference in the need for respiratory support one month after randomisation, but subsequently there was a trend towards a reduction in the proportion requiring respiratory support in the R-HuEpo group (difference at three months ?0.50, 95% confidence interval ?1.00, 0.17). During stay in hospital, the median number of blood transfusions was lower for infants in the R-HuEpo group (difference in medians ?2, 95% CI ?4, 0). The study was stopped early because of failure to recruit babies at the expected rate.CONCLUSIONS—R-HuEpo seems to reduce the number of days in oxygen for ill VLBW infants. These data could be used to construct a larger multicentre study to evaluate this effect further.  相似文献   
966.
The role of the placenta in controlling the supply of fatty acids to the fetus was investigated in term placentae (n=9) from normal pregnancies. The maternal side was perfused ex vivo for 90 min with a modified Krebs Ringer solution containing a physiological mixture of fatty acids and ratio of fatty acid to human albumin. There was no evidence of chain elongation and desaturation of the essential fatty acids. Relative to the value for oleic acid, the rate of transfer to the fetal circulation was: 1.30±0.02 (P<0.001) for linoleic acid, 1.61 ± 0.09 (P=0.002) for α-linolenic acid, 0.67 ± 0.10 (P=0.033) for arachidonic acid and 2.I0 ± 0.16 (P=0.003) for docosahexaenoic acid. For tissue accumulation the values were 1.47 ± 0.39 (P<0.001) for linoleic acid, 2.24 ± 0.37 (P=0.027) for α-linolenic acid, 9.84 ± 1.03 (P=0.001) for arachidonic acid, and 3.01 ± 0.79 (P=0.064) for docosahexaenoic acid. The order of selectivity for transfer from the maternal to the fetal circulation was docosahexaenoic>α-linolenic>linoleic>oleic>arachidonic acid. Such a mechanism would allow the preferential transfer of docosahexaenoic acid and the essential fatty acids to the fetal circulation, thereby protecting the polyunsaturated fatty acid supply to the fetus during a critical period of development.  相似文献   
967.
We conducted three separate experiments designed to determine the dietary methionine requirement, ability of cyst(e)ine to spare methionine, and the total sulfur amino acid requirement (TSAA) of juvenile yellow perch when fed the maximal amount of cyst(e)ine. The purified basal diet used in each experiment contained 33.6 g of crude protein/100 g diet and 12.0 g of lipid/100 g diet. In the first experiment,;>L-methionine was added to eight diets providing methionine concentrations ranging from 0.37 to 1.77 g/100 g diet in gradations of 0.2 g/100 g diet. Diets were fed for 12 wk to juvenile yellow perch initially weighing 4.7 g/fish. Broken-line analyses of weight gain and feed efficiency data indicated that the dietary methionine requirement was 1.0 g/100 g diet (3.1 g TSAA/100 g dietary protein) and 1.1 g/100 g diet (3.4 g TSAA/100 g dietary protein), respectively. In the second experiment, various ratios of L-cyst(e)ine and L-methionine were added to the basal diet and fed for 12 wk to determine the cyst(e)ine replacement value of yellow perch initially weighing 19.3 g/fish. Weight gain and feed efficiency (FE) data indicated that cyst(e)ine spared up to 51% of the methionine requirement. In the final experiment, graded levels of cyst(e)ine plus methionine in a ratio of 51:49 were added to the basal diet in gradations of 0.1 g/100 g diet (0.5 to 1.2 g TSAA/100 g diet) to determine the dietary total sulfur amino acid requirement. Diets were fed to satiation for 10 wk to fish initially weighing 8. 1 g. Broken-line analyses of weight gain, feed intake and FE data indicated that the dietary TSAA requirement was 0.85, 0.87 and 1.0 g of TSAA/100 g diet (2.5 to 3.0 g of TSAA/100 g of dietary protein), respectively. The majority of dietary TSAA requirements of fish are in the range of 2 to 4 g/100 g of dietary protein and are generally similar to those of both birds and swine, but lower than estimates for rodents.  相似文献   
968.
Radioactive strontium-90 concentrations in baby teeth obtained from Suffolk County, New York, rose steadily during the 1980s. Recent levels of strontium-90 are similar to those reported for babies born in the late 1950s-at the height of atmospheric nuclear weapons testing in Nevada. Strontium-90 concentrations increased concomitantly with increases in cancer incidence among Suffolk children under the age of 5 y, a result that mimicked parallel trends observed in the 1950s and early 1960s. Given that effects of strontium-90 on developing cells are most pronounced during the fetal and infant periods, escalating levels should be viewed as a factor in the recent decline in various child health status measures.  相似文献   
969.
970.
A retrospective review of patients in our practice who underwent abdominal panniculectomy to facilitate gynecologic cancer surgerywas performed. The objective of the study was to determine if pannicu-lectomy was a safe and useful procedure in the morbidly obese gyneco-logic cancer patient. A total of 12 patients underwent the procedure between 1992 and 1996. Optimal pelvic oncologic surgery was accom-plished in all 12 patients. All aspects of those procedures were per-formed by gynecologic oncologists. The Buchwalter retractor was usedin all cases. The patients' weights ranged from 170 to 429 pounds, with a mean of 275 pounds. The mean body mass index was 48, with a range from 37 to 67. Four patients had a history of diabetes mellitus. Nine patients healed without wound complications. Three patients developed superficial subcutaneous wound infections/necrosis that were successfully managed with office debridement. Abdominal panniculectomy is a reasonably safe procedure that makes radical pelvic surgery possible regardless of the patient's weight. Prolonged wound bulb suction drainage may decrease the incidence of wound necrosis/infection in these high-risk patients.  相似文献   
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