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1. Studies on the metabolism of the tricyclic antidepressant trimipramine (TMP) in the rat are described. 2. Twenty metabolites of TMP were isolated from rat urine after enzymatic hydrolysis and their structures were determined by a gas chromatographic-mass spectrometric (GC-MS) method. 3. Twelve TMP metabolites were the result of alicyclic (C10 or C11) oxidation in addition to the other metabolic pathways.  相似文献   
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Dietary fat, beef protein and fibre have been shown to modulatecancer risk in humans and the present study examined the biologicaleffects in human-flora-associated (HFA) rats of altering intakelevels within the normal human range. Two control groups, oneHFA and the other germfree (GF), consumed a human diet low infat, fibre and beef for 4 weeks; three other groups consumedhuman diets similar except for independent 3-fold increasesin fat, beef protein or fibre. After 2 weeks on the diets, magneticallyrecoverable microcapsules were given orally to the rats andsubsequently recovered from the faeces to assess endogenouscross-linking agents. After 4 weeks, measurements were madeof gut microfloral enzyme activities, hepatic activation ofdietary mutagens and hepatic DNA adducts by 32P-postlabelling.Activation in vitro of the dietary mutagens 2-amino-3-methyl-3H-imidazo[4,5-f]quinolline (IQ) and 2-amino-l-methyl-6- phenytimidazo[4,5-b]pyridine(PhIP) by hepatic S9, formation of endogenous hepatic DNA adductsin vivo and the ß-glucuronidase activity of caecalcontents were all increased in the sequence high fat > highfibre > high beef = control. Of the two DNA adducts foundin all HFA rats, only one was present in GF controls, indicatingthat the human gut microflora (subject to human dietary modulation)either releases a DNA-adducting product able to act outsidethe gastrointestinal tract, or stimulates the generation ofsuch a product by mammalian processes. Caecal nitrate reductaseactivity was highest in rats fed the high beef diet, whilstentrapment of cross-linking agents was highest in those fedthe high fibre diet. These results show that risk-related componentsof human diets interact with human gut microflora to modulatethe production of endogenous DNA-adducting and cross-linkingsubstances.  相似文献   
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The effect of 4 mg oral naloxone on preoperative gastric volume and pH of gastric aspirate was studied in a double-blind, randomized study. Twenty patients received 10 ml of naloxone (4 mg) mixed with 10 ml of orange juice, and 20 patients received 10 ml of isotonic saline mixed with 10 ml of orange juice, 2 h before surgery. Gastric content was obtained immediately after intubation of the trachea. No significant difference in gastric volume and pH of gastric aspirate was found between the two groups. It is concluded that naloxone does not affect gastric emptying and gastric acid secretion to a degree great enough to protect against aspiration of gastric contents into the lungs.  相似文献   
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OBJECTIVE--To assess the feasibility of monitoring health outcomes in a routine hospital setting and the value of feedback of outcomes data to clinicians by using the SF 36 health survey questionnaire. DESIGN--Administration of the questionnaire at baseline and three months, with analysis and interpretation of health status data after adjustments for sociodemographic variables and in conjunction with clinical data. Exploration of usefulness of outcomes data to clinicians through feedback discussion sessions and by an evaluation questionnaire. SETTING--One gastroenterology outpatient department in Aberdeen Royal Hospitals Trust, Scotland. PATIENTS--All (573) patients attending the department during one month (April 1993). MAIN MEASURES--Ability to obtain patient based outcomes data and requisite clinical information and feed it back to the clinicians in a useful and accessible form. RESULTS--Questionnaires were completed by 542 (95%) patients at baseline and 450 (87%) patients at follow up. Baseline health status data and health outcomes data for the eight different aspects of health were analysed for individual patients, key groups of patients, and the total recruited patient population. Significant differences were shown between patients and the general population and between different groups of patients, and in health status over time. After adjustment for differences in sociodemography and main diagnosis patients with particularly poor scores were identified and discussed. Clinicians judged that this type of assessment could be useful for individual patients if the results were available at the time of consultation or for a well defined group of patients if used as part of a clinical trial. CONCLUSIONS--Monitoring routine outcomes is feasible and instruments to achieve this, such as the SF 36 questionnaire, have potential value in an outpatient setting. IMPLICATIONS--If data on outcomes are to provide a basis for clinical and managerial decision making, information systems will be required to collect, analyse, interpret, and feed it back regularly and in good time.  相似文献   
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