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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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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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Proximal femoral focal deficiency, an uncommon congenital anomaly, necessitates early radiologic classification for surgical planning and treatment. Objective radiographic criteria, including femoral length index, acetabular depth index, acetabular angle index, and shape of the proximal femur were determined in 49 patients before cartilaginous ossification of the femoral capital epiphysis; final classification was based on follow-up radiographs or findings at arthrography or surgery. These parameters were analyzed to determine the accuracy and contributions of each in classification. Correct classification into one of three groups was possible in 86% of cases with use of three of the parameters: femoral length index, acetabular depth index, and shape of the proximal femur. The acetabular angle was found to contribute insignificantly to classification. Magnetic resonance imaging, used in only one case, depicted the nonossified cartilaginous femoral capital epiphysis, thus obviating the need for invasive diagnostic procedures and facilitating early classification.  相似文献   
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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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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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A feasibility study was instituted to determine if women with postmenopausal breast cancer would follow a low-fat diet (20% of kcal) for at least four months. Nineteen women, whose baseline food intake was 1,504 +/- 420 kcal with 56 +/- 16 g of fat, reported a decrease in fat intake to 21 +/- 6 g after two months of dietary intervention. Serum concentrations of cholesterol, HDL cholesterol, and estradiol were significantly reduced by the fifth month on the diet. We conclude that self-selected patients can adhere to a low-fat diet, and that serum cholesterol may serve as an indicator of dietary compliance.  相似文献   
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