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Fix Joseph A. Alexander Jose Cortese Margot Engle Karen Leppert Paula Repta A. J. 《Pharmaceutical research》1990,7(4):384-387
Short-chain alkyl esters of L-dopa were administered to rats and mice via oral and rectal routes. Plasma L-dopa esters and L-dopa were determined in the systemic and portal circulation by HPLC. A comparison of isopropyl, butyl, and 4-hydroxybutyl esters of L-dopa demonstrated significantly higher levels of the esters in both systemic and portal blood samples following rectal administration than following oral administration. In most cases, oral administration resulted in nondetectable (<0.01 µg/ml) levels of the esters in plasma. Correspondingly, the plasma levels of L-dopa itself were consistently higher following rectal administration. At very high oral doses (500 mg L-dopa equivalents/kg body weight), systemic plasma levels of the butyl ester could be detected (1.25 µg/ml at 10 min), which might indicate saturation of the esterase activity of the small intestine. These studies indicate that the systemic availability of L-dopa from short-chain alkyl esters of L-dopa may be best optimized by rectal administration, which avoids the relatively high esterase activity characteristic of the small intestine. 相似文献
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RAFAEL BEYAR M.D. D.Sc. ARIEL ROGUIN M.D. JAAP HAMBURGER M.D. RE SAAIMAN M.D. ANTONIO L. BARTORELLI M.D. CARLO DiMARIO M.D. ANTONIO COLOMBO M.D. CHRISTIAN W. HAMM M.D. CHRISTOPHER J. WHITE M.D. J. MARCO M.D. PATRICK W. SERRUYS M.D. Ph.D. 《Journal of interventional cardiology》1997,10(4):277-286
The beStent is a new stainless steel, balloon-expandable mesh stent which has a unique serpentine design. Rotation of the unique low stress junctions upon expansion leads to orthogonal locking of the wires, maximizing radial strength and assuring zero shortening. The stent has delineating gold markers which assure precise positioning. We aim to present the initial acute results in a pilot registry for stent evaluation. Two hundred eighty-four stents were used in a total of 217 patients (age 57.9 ± 3.10 years; 178 males; 39 females) in seven centers, for variable indications. Stents of 15-, 25-, and 35-mm length were used. The arteries treated were the left anterior descending (n = 112, 42%), circumflex (n = 54, 20.2%), right coronary (n = 95, 35.5%), left main (n = 1, 0.4%), and vein graft (n = 5, 1.9%). Lesion types were: A in 42 patients (16.5%); B1 in 53 patients (20.7%); B2 in 81 patients (31.8%); and C in 79 patients (31%). One hundred fifty-nine patients required one stent, 40 patients required two stents, and 18 patients required three or more stents. Anticoagulation protocol included procedural heparin with aspirin with/without ticlopidine. Smooth angiographie results were obtained in all cases with no plaque herniation. Acute angiographic success was obtained in 97% of the patients, and acute clinical success in 95% of the patients. Complications within 30 days were: 3 deaths (1.4%) (2 noncardiac); 2 (0.9%) myocardial infarctions; and 2 (0.9%) stent thromboses. Therefore, the beStent is useful in treatment of complex lesions of variable length and complexity, providing excellent acute results with a low complication rate, in spite of unfavorable basic clinical and angiographie characteristics. 相似文献
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The authors present background on the gestalt-experiential understanding of resistance, conceptualized to be either resistance to awareness or resistance to contact. The authors discuss why they do not use the term resistance and describe the phenomena as a client's self-protective attempt to avoid the anxiety necessitated by change. Such resistant behaviors occur outside a client's awareness and often result in an ambivalence or conflict about change. The authors also describe using in-session experiments as a way to engage with the client in exploring such a state of ambivalence or conflict. Finally, they respond to the case studies presented elsewhere in this issue and propose intervention strategies consistent with the gestalt-experiential perspective. 相似文献
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Factors affecting breastfeeding among women of Mexican origin or descent in Los Angeles. 总被引:2,自引:0,他引:2
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Data on breastfeeding intentions and behavior were collected in prenatal and postpartum interviews as part of a study on first birth among 518 women of Mexican origin or descent in two Los Angeles hospitals. The prenatal intentions of 82 per cent of the women to breastfeed were maintained postpartum in one hospital but dropped sharply in the other. A greater number of hours a day with the baby in the hospital and earlier initiation of breastfeeding were associated with the hospital where prenatal breastfeeding intentions were more likely to be carried out. The intention to work postpartum was associated both with the decision not to breastfeed at all and with shorter intended duration of breastfeeding. 相似文献
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Perfluorochemicals as US contrast agents for tumor imaging and hepatosplenography: preliminary clinical results 总被引:3,自引:0,他引:3
Mattrey RF; Strich G; Shelton RE; Gosink BB; Leopold GR; Lee T; Forsythe J 《Radiology》1987,163(2):339-343
In animals, perfluorochemicals (PFCs) are effective ultrasound (US) contrast agents that produce hepatic, splenic, and tumor enhancement. The use of Fluosol-DA 20%, an emulsion of perfluorodecalin and perfluorotripropylamine, was studied in nine non-critically ill patients with cancer who had liver lesions. US studies without Fluosol were compared with studies obtained 24, 48, and 72 hours after Fluosol infusion. Vital signs and extensive laboratory analyses are performed before and after Fluosol infusion. Liver metastases from colonic, pancreatic, and gastric carcinoma exhibited rim or diffuse enhancement after a Fluosol dose of 1.6 g/kg or greater. Fluosol produced echogenic enhancement of the liver and spleen relative to kidney at a dose of 2.4 g/kg, allowing the detection of nonenhancing lesions. In addition, Fluosol at a dose of 1.6 g/kg or greater allowed detection of lesions not seen before contrast medium was administered in three of the seven patients studied. There was a mild increase in the level of serum glutamic oxaloacetic transaminase in two patients, one given 2.4 and the other 3.2 g/kg of Fluosol. Mild and transient allergic reactions without change in vital signs were experienced by two patients. 相似文献
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Exploration of the relative roles of family dynamics and release of constrained, negative emotion in changing pain and depressive symptoms. Eighteen patients presenting mild to moderate depression and diagnoses of psychogenic pain disorder were randomly assigned to 1 of 2 treatment groups. One group was designed to facilitate the release of constrained and overcontrolled negative affect while the other was designed to provide information about pain and depression. Findings suggest that initial incongruity between patient's and significant other's ratings of family relationships retard changes in pain status and depressive symptoms. No significant differences were noted between patients who were taught to express negative feelings and those who were taught simply to understand those feelings. Results are discussed in terms of theories about family dynamics in the initiation and maintenance of pain conditions and in terms of the role of constrained affect as a precursor to both psychogenic pain and depression. 相似文献
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