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101.
102.
C Finke C Juge M Goumaz O Kaiser R Davies A G Burger 《Journal of endocrinological investigation》1987,10(2):157-162
The induction of mixed function hepatic oxygenases by rifampicin is known to increase the metabolic clearance rate (MCR) of T4. By performing T3 and rT3 kinetics we have shown that rifampicin also increases the MCR of T3 and rT3. Using the fall of serum T4 during TSH suppression as an indirect marker of the production rate (PR) of T4, we have demonstrated that there was no major change in monodeiodination nor any shift to either 5'- or 5-monodeiodination. Rifampicin stimulates in mice the mixed function hepatic oxygenases. However, we were unable to increase hepatic deiodinase activity (deiodinase type I) in this species. It is therefore possible that the increased MCR of T4 in man is not mediated by an increased conversion rate either. As mixed function hepatic oxygenases are known to increase hepatic conjugation it is suggested that rifampicin increases the biliary excretion of iodothyronine conjugates. 相似文献
103.
104.
Microinjections of various alpha 1-adrenoceptor agonists including phenylephrine and phenylpropanolamine into the paravenricular hypothalamic nucleus (PVN) suppress food intake in rats, suggesting that this receptor type might act in opposition to previously identified facilatory PVN alpha 2-adrenoceptors in the modulation of feeding. In the present experiments, we examine the effects on food and water intake of intra-PVN as well as systemic injection of cirazoline, a highly potent alpha 1-adrenoceptor agonist. In Experiment 1, intra-PVN microinjection of cirazoline (0, 3, 6, 12 and 24 nmol) suppressed food intake (ED50 = 23.4 nmol) without significant effects on water intake. In Experiment 2, systemic injection of cirazoline (0, 0.05, 0.1, 0.2, 0.4 mg/kg) also markedly suppressed food intake (ED50 = 0.05 mg/kg i.p.), with a less potent action on water intake (ED50 = 0.22 mg/kg i.p.). The results of this study as well as our previous investigations strongly support the notion that alpha 1-adrenoceptors within rat PVN act to reliably suppress food intake. 相似文献
105.
106.
Uroscopy in the 21st century: high-field NMR spectroscopy 总被引:1,自引:1,他引:0
Neild GH; Foxall PJ; Lindon JC; Holmes EC; Nicholson JK 《Nephrology, dialysis, transplantation》1997,12(3):404-417
From the experiments described, it can be seen that there are different
research approaches that can be taken and these are summarized in Table 1.
Whereas much scientific research is principally hypothesis led, there
remains, nevertheless, an important place for exploratory research. High
resolution NMR can measure, directly and simultaneously, a wide range of
endogenous metabolites in biological fluids and has the unique capability
of providing structural information on the metabolites detected. It has
proved to be a powerful research tool with which to study inherited
metabolic diseases, renal disease, drug metabolism, and toxicity, and can
be used to monitor the effects of drug therapy. For instance, by using a
library of experimental toxins one can map the metabolic profile of
site-specific nephron injury. With this approach in man one could
eventually take an unknown disease such as Balkan nephropathy and predict
the initial site of tubular injury, the mode of injury and therefore the
kind of toxin capable of producing that injury. NMR spectroscopic
techniques are still advancing rapidly, with ever increasing sensitivity
and sophistication of NMR pulse sequences to enhance structural elucidation
in complex mixtures. Given the advances in directly coupled HPLC-NMR and
even HPLC-NMR-mass spectroscopy it is likely that these technologies in
conjunction with pattern recognition will make major contribution to our
understanding of renal processes and provide new diagnostic insights in the
21st century.
相似文献
107.
Electrosurgery techniques have been used in dentistry as an aid to soft tissue management for nearly 60 years. However, it was not until the late 1960s that the principles of electrosurgery were understood and improved equipment became available. Part 1 of the two-part series covered the theory behind using this technique. Part 2 will now discusses the clinical applications. 相似文献
108.
109.
G R Goldberg A M Prentice H L Davies P R Murgatroyd 《European journal of clinical nutrition》1988,42(2):137-144
The FAO/WHO/UNU recommendations for energy requirements assume that the energy cost of sleep is equal to the basal metabolic rate (BMR). We have tested the validity of this assumption by analysing overnight and BMR measurements made by whole-body indirect calorimetry. Data from 80 healthy subjects measured on a total of 246 occasions have been used. In a subgroup of 40 normal lean subjects the mean ratio of overnight metabolic rate (Overnight MR): BMR was 0.95 (range 0.85 - 1.02, s.d. 0.04). The mean ratio of lowest sleeping metabolic rate (Lowest SMR): BMR was 0.88 (range 0.83 - 0.96, s.d. 0.04). Ratios of Overnight MR: BMR were not significantly affected by different levels of exercise on the preceding day. This ratio was significantly higher for subjects who were obese, late pregnant or attached to ECG electrodes. With the exception of the late pregnant subjects these groups had the same Lowest SMR:BMR ratios as the normal lean subjects, indicating that the higher Overnight MR was caused by disturbed sleep. The data suggest that the use of BMR to estimate overnight energy expenditure would introduce an average overestimate of approximately 5 per cent during the actual hours of sleep, but that when applied over 24 h the error becomes negligible. 相似文献
110.
Toxicity of diethyltoluamide-containing insect repellents 总被引:1,自引:0,他引:1