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Alcohol is an important risk factor for human oesophageal cancer. There is evidence from epidemiological studies that some
specific alcoholic drinks, e.g. Calvados apple brandy, are associated with a greater risk than others. Alcohol induces cytochrome
P450 2E1 (CYP2E1) and the hypothesis was tested that different alcoholic beverages, containing a variety of alcoholic compounds,
could differentially induce expression of cytochrome P450 enzymes. Twelve groups of five rats each were treated for 3 days
with different alcoholic beverages (ethanol alone, whisky, farm-produced or commercial Calvados brandy, beer, cider, wine)
adjusted to 4, 10 or 20% of ethanol in drinking water. Immunoblotting using a monoclonal antibody specific for rat CYP2E1
revealed a single protein band in liver microsomes. Densitometric quantitation of microsomal proteins demonstrated a significant
two-, three- and sixfold increase in band intensity after treatment with ethanol concentrations of 4, 10 and 20% respectively,
compared to control rats drinking water alone. There was a dose-dependent increase in liver microsomal metabolism of CYP2E1
substrates (para-nitrophenol and dimethylnitrosamine) in ethanol-treated rats. However, there were no significant differences
in the level of CYP2E1 protein or enzymatic activity between the different alcoholic beverages at the same ethanol concentration.
There was a slight increase in hepatic CYP1A-related enzymatic activities in the alcohol-treated rats compared to the controls,
but no difference between the treated groups either with dose of ethanol or type of beverage. These data show that induction
of CYP2E1 with acute alcohol treatment is predominantly determined by the ethanol content of the beverage.
Received: 10 February 1997 / Accepted: 26 May 1997 相似文献
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E. Andrs G. Kaltenbach E. Noel M. Noblet‐Dick A.‐E. Perrin T. Vogel J.‐L. Schlienger M. Berthel J. F. Blickl 《International journal of laboratory hematology》2003,25(3):161-166
Background: It has been suggested that oral cobalamin (vitamin B12) therapy may be an effective therapy for treating cobalamin deficiencies related to food‐cobalamin malabsorption. However, the duration of this treatment was not determined. Patients and method: In an open‐label, nonplacebo study, we studied 30 patients with established cobalamin deficiency related to food‐cobalamin malabsorption, who received between 250 and 1000 μg of oral crystalline cyanocobalamin per day for at least 1 month. Endpoints: Blood counts, serum cobalamin and homocysteine levels were determined at baseline and during the first month of treatment. Results: During the first month of treatment, 87% of the patients normalized their serum cobalamin levels; 100% increased their serum cobalamin levels (mean increase, +167 pg/dl; P < 0.001 compared with baseline); 100% had evidence of medullary regeneration; 100% corrected their initial macrocytosis; and 54% corrected their anemia. All patients had increased hemoglobin levels (mean increase, +0.6 g/dl) and reticulocyte counts (mean increase, +35 × 106/l) and decreased erythrocyte cell volume (mean decrease, 3 fl; all P < 0.05). Conclusion: Our findings suggest that crystalline cyanocobalamin, 250–1000 μg /day, given orally for 1 month, may be an effective treatment for cobalamin deficiencies not related to pernicious anemia. 相似文献
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Several public and private groups have set minimum procedure-specific volume standards. Such standards reflect concerns about hospital quality and cost. In-hospital mortality rates are often taken as one measure of quality. To learn about variations in in-hospital mortality rates, we analyzed data on patients who underwent any of seven surgical procedures from a national cohort of 521 hospitals observed continuously between 1972 and 1981. On the average, mortality rates fell as the number of procedures performed annually at the hospital rose. Volumes at which mortality rates reached minimum levels were far higher than actual volumes achieved by the vast majority of hospitals. However, knowledge of hospital volumes left the major part of variation among hospitals' procedure-specific mortality rates unexplained. Many hospitals with low volumes of certain procedures had no associated deaths. Hospitals experienced appreciable year-to-year variation in mortality even though mortality rates fell with the number of years the procedure was performed at the hospital. Correlations among mortality rates for the procedures were low, suggesting that variation in rates is procedure rather than hospital specific. State rate-setting programs had no effect on mortality rates associated with the procedures analyzed. For several reasons, we conclude that an adequate statistical basis for setting minimum volume standards does not presently exist. 相似文献
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M Perrin 《Phlébologie》1988,41(1):115-134
In which circumstances does a surgeon request phlebograms and which ones? What is the contribution of phlebography regarding therapeutic indications and surgical technique. 相似文献
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Pelvic floor muscle training with biofeedback and bladder training in elderly women: a feasibility study. 总被引:1,自引:0,他引:1
Louise Perrin Sharon Wood Dauphinée Jacques Corcos James A Hanley George A Kuchel 《Journal of wound, ostomy, and continence nursing》2005,32(3):186-199
OBJECTIVE: It is generally assumed that interventions used to treat urinary incontinence (UI) in young women could simply be applied to older competent and motivated women, but these assumptions have not been formally tested. The purpose of this study was to determine the feasibility of using physical therapies to treat UI in older women. DESIGN: Twelve-week time series. SETTINGS AND SUBJECTS: We recruited women older than 75 years with UI from an outpatient urology clinic and a waiting list for incontinence surgery. METHODS: After a baseline evaluation, the women collected data on their incontinence symptoms and bladder habits for 3 weeks using the 72-hour voiding diary and the 24-hour pad test. They then received 6 physical therapy treatments consisting of a combination of bladder training and pelvic floor muscle training assisted with biofeedback for 6 weeks. This was followed by another 3-week period of data collection and a final evaluation. RESULTS: Ten women participated in the study; 7 completed it. They were all comfortable with the treatment. They complied with the study demands in terms of attendance at treatment session (100%), data collection (96%), and completion of exercises at home (82%). The authors observed a decrease in the number of incontinent and urgency episodes. CONCLUSION: This preliminary study demonstrates that some women older than 75 years are good candidates to undertake physical therapies for UI and follow study demands. Random controlled studies that include this population will provide evidence regarding the effectiveness of these therapies. 相似文献
10.
Patients with occlusive arterial diseases, tumors invading the vascular structures of the skull base or giant aneurysms may benefit from an EICB. Most of the time this can be achieved using a scalp artery. But in cases of a thrombotic ECA, excessively short or thin scalp branches or destruction of those by prior cranial surgery, an interposed venous graft is needed. In the author's series, which consists of 16 patients, the bypass was performed for ICA occlusive diseases in 5, before complete removal of cavernous sinus tumours in 4 and prior to cervical internal carotid ligation for giant aneurysms in 7. The grafts were always harvested from the internal saphenous vein. The proximal site of implantation was CCA (2 cases), ECA (6 cases), ICA (1 case), superior thyroid A (2 cases)--i.e. 11 long grafts--and the trunk of the occipital A--i.e. short grafts in 5 cases. In this series, there was no mortality and no morbidity related to revascularization. The early patency rate, checked with arteriography, was 62.5% (10 cases) and the late one 56.2% (9 cases). Causes of failure, partially related to technical difficulties in 2 cases, were almost always due to an insufficient extra-intracranial pressure gradient (4 cases). Excepted in one case, there was no correlation between patency and the use or not of anti-aggregant and/or heparin. Literature data are summarized and discussed. They all confirm the importance--besides the absence of technical errors--of a sufficient extra-intracranial gradient for obtaining a good patency rate. 相似文献