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排序方式: 共有1159条查询结果,搜索用时 15 毫秒
21.
C T Wass S H Rose R J Faust K P Offord A M Harris 《Journal of clinical anesthesia》1999,11(2):150-163
STUDY OBJECTIVE: To identify factors responsible in the selection of anesthesiology as a career by Mayo Clinic house staff (i.e., residents and clinical fellows); to evaluate their level of satisfaction with their choice of career and training program, and their perceptions of the future for anesthesiology trainees. DESIGN: Cross-sectional analysis using a questionnaire survey of 67 house staff enrolled in the anesthesiology training program during the 1995-1996 academic year. SETTING: Mayo Clinic, Rochester, MN. MEASUREMENTS AND MAIN RESULTS: Forty-eight (72%) of those surveyed responded to the questionnaire. Data were analyzed using the Chi-square and Mann-Whitney rank sum tests. A p-value less than or equal to 0.05 was considered statistically significant. The most frequently cited reasons for selecting anesthesiology as a career included the following: it is a "hands-on" specialty, it involves clinical application of physiology and pharmacology, and it provides immediate gratification in one's work. The most frequently cited reasons for selecting our training program were the diversity of training experience, prestige associated with Mayo Clinic, and employment opportunities following training. Forty-four (92%) felt downsizing of anesthesiology training programs was a national trend, 26 (54%) anticipated difficulty obtaining a job following training, and 16 (33%) felt they had future job security. Overall, 47 (98%) were happy with their career choice, and 40 (83%) would choose anesthesiology as a career if they were now graduating from medical school. All 1996 graduates found suitable employment without difficulty. CONCLUSIONS: Our data indicate that selection of a career in anesthesiology and training program are strongly associated with concerns regarding educational experiences and postgraduate employment opportunities. 相似文献
22.
Interactive suppression of aberrant crypt foci induced by azoxymethane in rat colon by phytic acid and green tea 总被引:1,自引:2,他引:1
Several epidemiological studies point to a strong correlation between
nutrient composition of the diet and cancer of the colon. Phytic acid,
present in grains, has been credited with reducing the risk of cancer of
the colon. A number of reports are available indicating the benefits of
green tea consumption in reducing the risk of stomach, lung and skin
cancer, but little data are available on the effect of green tea in
reducing the risk of colon cancer. Also, there are no studies on the
combined effect of these compounds on colon tumorigenesis. Thus the primary
objective of this investigation was to elucidate the combined effects of
green tea and phytic acid on colonic preneoplastic lesions and the Phase II
enzyme glutathione S-transferase. Fisher 344 male weanling rats were
divided into nine groups of 15 rats each and fed the experimental diet for
13 weeks. Rats received two s.c. injections of azoxymethane in saline at 16
mg/kg body wt at 7 and 8 weeks of age. Rats received three levels (0, 1 and
2%) of phytic acid with three levels (0, 1 and 2%) of green tea within each
phytic acid level in a 3 x 3 factorial experiment. Results indicate that
while green tea had a marginal effect (P < 0.14), phytic acid
significantly reduced the incidence of aberrant crypt foci (P < 0.008).
The interaction between green tea and phytic acid was significant (P <
0.029 for distal and < 0.0168 for entire colon) and positive, pointing
to a synergistic effect of green tea and phytic acid.
相似文献
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Prof. M. Berger P. A. Halban L. Girardier J. Seydoux R. E. Offord A. E. Renold 《Diabetologia》1979,17(2):97-99
Summary The absorption of subcutaneously injected insulin was examined by injecting semisynthetic [3H] insulin in anaesthetized pigs and subsequently analysing the tissue excised from the injection site. Contrary to previously accepted views, a significant proportion of insulin was degraded at the injection site. The disappearance of intact [3H] insulin from the injection site followed a monoexponential function with a half-time of 59 min. 相似文献
27.
Circadian variation in ionized calcium and intact parathyroid hormone: evidence for sex differences in calcium homeostasis 总被引:3,自引:0,他引:3
M S Calvo R Eastell K P Offord E J Bergstralh M F Burritt 《The Journal of clinical endocrinology and metabolism》1991,72(1):69-76
The rate of bone loss with age and the incidence of osteoporosis are greater in women than men, which led us to question whether subtle sex differences may occur in the circadian variation of serum ionized calcium (iCa) and PTH. We measured iCa hourly and intact PTH every 2 h for 26 h in 25 women (21-69 yr) and 24 men (20-67 yr) consuming self-selected diets. Urine was collected at 0800-1600, 1600-2400, and 2400-0800 h. Serum iCa levels followed a circadian rhythm in both sexes (P less than or equal to 0.01), and the patterns differed between sexes, notably during early morning, when serum iCa levels were lower in women (P = 0.02). Urinary calcium excretion and fractional excretion of calcium declined in both sexes at night (2400-0800 h), but the decline in men was significantly greater (P = 0.02). Similarly, the percent reduction in urinary calcium excretion at night was greater in men than in women (34% vs. 17%; P less than or equal to 0.05). In women, 26-h mean serum iCa values correlated significantly with total daily calcium intake (r = 0.44; P = 0.03). Serum intact PTH levels showed a significant circadian pattern in both sexes (P less than or equal to 0.001). The patterns of serum intact PTH differed between the sexes (P = 0.05), with an earlier and greater increase at night in men. This blunted nocturnal rise in PTH in women may explain the poor nocturnal adaptation to fasting found in women who, despite lower calcium intake, did not reduce urinary calcium loss at night as effectively as men. 相似文献
28.
BACKGROUND & AIMS: Shwachman syndrome is an inherited condition with multisystemic abnormalities, including exocrine pancreatic dysfunction. The aim of this study was to evaluate the occurrence and progression of features in a large cohort of patients. METHODS: Clinical records of 25 patients with Shwachman syndrome were reviewed. RESULTS: Mean birth weight (2.92 +/- 0.51 kg) was at the 25th percentile. However, by 6 months of age, mean heights and weights were less than the 5th percentile. After 6 months of age, growth velocity was normal. Severe fat maldigestion due to pancreatic insufficiency was present in early life (fecal fat, 26% +/- 17% of fat intake; age, < 2 years). Serial assessment of exocrine pancreatic function showed persistent deficits of enzyme secretion, but 45% of patients showed moderate age-related improvements leading to pancreatic sufficiency. Neutropenia was the most common hematologic abnormality (88%), but leukopenia, thrombocytopenia, and anemia were also frequently encountered. Patients with hypoplasia of all three bone marrow cellular lines (n = 11) had the worst prognosis; 5 patients died, 2 of sepsis and 3 of acute myelogenous leukemia. Other findings included hepatomegaly and/or abnormal liver function test results and skeletal abnormalities. CONCLUSIONS: A wide and varied spectrum of phenotypic abnormalities among patients with Shwachman syndrome is described. Pancreatic acinar dysfunction is an invariable abnormality. Patients with severe bone marrow involvement may have a guarded prognosis. (Gastroenterology 1996 Dec;111(6):1593-602) 相似文献
29.
S F Davies K P Offord M G Brown H Campe D Niewoehner 《The American review of respiratory disease》1983,128(3):473-475
We measured urine desmosine by radioimmunoassay in 157 subjects. Desmosine excretion (expressed as desmosine/creatinine ratio) did not correlate with ventilatory function (assessed by spirometry) or with current smoking status or total lifetime cigarette consumption. We conclude that measurement of urine desmosine may not be useful as an indirect measurement of elastolysis in cigarette smokers. 相似文献
30.