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781.
Effects of continuous feeding flavonoids (flavone, flavanone, and tangeretin) on drug-metabolizing enzymes in rat liver were investigated to ascertain how long feeding is required to reach maximal induction and to determine whether maximal induction is maintained for a long period of feeding. In the first experiment rats received a diet containing 10 mmol flavonoid/kg dry matter for 4, 8, 16, or 32 d. The second experiment was designed to examine the time course for induction during the first 4 d. The kinetics of induction depended on the chemical structure of the flavonoid and was different from one enzyme to another. Flavone increased P450 1A and P450 2B apoproteins and stimulated many enzyme activities. A significant increase of P450 1A1/2 proteins, ethoxyresorufin O-deethylase (EROD), and methoxyresorufin O-demethylase (MROD) activities occurred as early as 6 h after the first administration, and a gradual increase was observed up to 4 d of feeding. P450 2B1/2 proteins and pentoxyresorufin O-depentylase (PROD) activity were also increased but after a lag period when compared with P450 1A1/2 proteins. EROD and MROD activities declined after 4 d, whereas PROD activity remained steady during 32 d of flavone feeding. Glutathione transferase (GST) and p-nitrophenol UDP-glucuronosyl transferase (UGT) activities were also increased. The maximal induction was reached by 4 d of feeding for UGT and after a longer duration of feeding (16 d) for GST. Flavanone treatment induced mostly P450 2B1/2 proteins and PROD, GST, and UGT activites. After 4 d of feeding, P450 2B1/2 proteins and PROD activity declined whereas GST and UGT activities remained steady. Tangeretin treatment produced changes similar to flavone but of lesser magnitude and after a longer delay.  相似文献   
782.
OBJECTIVES: The primary aim of this prospective multi-centre study involving patients undergoing elective abdominal aortic aneurysm (AAA) surgery was to investigate the relationship between intraoperative intravenous heparinisation, blood loss during surgery and thrombotic complications. METHODS: Two hundred and eighty-four patients were randomised to receive intravenous heparin (n = 145) or no heparin (n = 139). Groups were evenly matched for age, sex, weight, aneurysm size, haemoglobin concentration, platelet counts and distal occlusive disease measured by ankle/brachial systolic pressure. RESULTS: There were no statistically significant differences in blood loss (median 1400 ml vs. 1500 ml; z = 0.02, p = 0.98, 95% C.I. = -200 to 200), blood transfused (4.0 units vs. 4.0 units; z = 1.09, p = 0.28, 95% C.I. = -1 to 0) or distal thrombosis between the two groups. However, analysis of the clinical outcome revealed that 5.7% of the non-heparin group but only 1.4% of the heparinised patients suffered a fatal perioperative myocardial infarction (MI); p < 0.05. All MI, including non fatal events, affected 8.5% and 2% respectively (p = 0.02). CONCLUSIONS: Heparin does not increase blood loss or the need for blood transfusion during surgery. Heparin is not necessary to prevent distal thrombosis when the aorta is cross clamped. The results of the study are consistent with the known mechanisms leading to intraoperative MI and strategies for its prevention. Intravenous heparin, given before aortic cross clamping, is an important prophylaxic against perioperative MI in relation to AAA surgery.  相似文献   
783.
784.
The fetus is dependent upon the placenta for transport to it of all nutrients for energy and growth. The primary nutrients crossing the placenta are glucose, lactic acid, free amino acids, free fatty acids, and ketone bodies. Under normal circumstances, it appears that glucose is the primary energy source. In abnormal conditions there is the possibility that energy requirements may be met also by protein-amino acid oxidation and ketone body metabolism. The fetal brain may be quite adept in the use of ketone bodies. In all transport phenomena, the placenta intervenes by diverting nutrients into its own intermediary metabolism. For a more extensive consideration of these factors, several in-depth reviews are recommended. To better understand abnormalities of intrauterine growth, we need much more specific information about the mechanisms of placental transport and the intermediary metabolism of the placenta and fetus. When these are adequately in states of normal and abnormal intrauterine growth, we can then consider methods of metabolic intervention which will correct intrauterine growth failure and, hopefully, eliminate its hazards to the fetus and child.  相似文献   
785.
The acceptance and effectiveness of medication cards and booklets for cardiovascular patients were evaluated. Approximately one month after discharge counseling which included the written reinforcements, 22 out of 50 patients discharged from cardiothoracic surgery and cardiovascular medicine units were questioned to assess patient usage of the medication cards/booklets and patient knowledge of their particular drugs. All patients except one indicated that they had read the material after leaving the hospital, and many had read it more than once. The effectiveness of the material was found to be only partially acceptable when general and specific medical questions were asked. The names and uses of most of the drugs taken by the patients were identified correctly.  相似文献   
786.
The muscle relaxant dantrolene sodium acts directly and specifically on skeletal muscle, unlike other pharmacological agents which affect the central nervous system or act at the nueromuscular junction. Dantrolene sodium markedly suppresses the release of calcium previously sequestered by skeletal, but not cardiac, muscle sarcoplasmic reticulum. No effect in the total amount of calcium accumulated was found. In situ, the drug may reduce the amount of calcium necessary for muscle contraction.  相似文献   
787.
788.
A survey of cancer incidence among Alaska Natives for the 5-year period 1969-73 revealed fewer cancer cases overall than expected in relation to US rates, but significantly increased risk for certain cancer sites: the nasopharynx in both sexes (with excesses over 15-fold), the liver in males, and the salivary glands, gallbladder, kidney and thyroid in females. Compared with earlier reports, the observations suggest marked changes in cancer incidence among Alaska Natives over the past two decades, with declines in esophageal and invasive cervical cancers, and increases in cancers of the lung, colon and rectum.  相似文献   
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