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21.
1. The antagonistic actions of parafluorohexahydrosiladiphenidol (pFHHSiD) at muscarinic receptors has been studied in cardiac muscle, smooth muscle and cell culture preparations. In this paper, the classification scheme of Doods et al. (1987) is employed. This scheme is based upon differential affinities of muscarinic antagonists. pFHHSiD exhibited high pA2 values at M3 receptors mediating contractions of guinea-pig ileum and oesophageal muscularis mucosae (7.8 and 8.2 respectively) whereas low values were determined at M2 receptors mediating negative inotropic responses in guinea-pig atria (6.0). Intermediate pA2 values were determined at M1 receptors mediating contractions of the canine femoral and saphenous veins. 2. The pA2 values of pFHHSiD at receptors mediating endothelial-dependent relaxation of rat aortic rings, rabbit jugular vein and canine femoral artery (7.6-7.9) were similar to those determined on the ileum. However, the pA2 values of pFHHSiD at receptors mediating contractions of the guinea-pig trachea (7.1), which has been previously shown to possess M3 receptors, were different from those determined in the ileum. 3. The similarity in pA2 values of pFHHSiD between the M3 receptors in guinea-pig ileum and the receptors mediating endothelial-dependent relaxations provide further evidence for the role of M3 receptors in this vascular response. Taken together, pA2 values for pFHHSiD range from 7.1 to 8.2, depending upon the M3 preparation used. The selectivity of the compound therefore for the M3 versus the M2 muscarinic receptor ranged from 13 to 163 fold.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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ABSTRACT: Managed care organizations (MCOs) joined local and state public health agencies in a pilot effort to improve hepatitis B immunization rates of adolescents in an urban and a suburban/rural school district. The pilot also explored issues inherent in public and private collaboration on population health improvement.
Local public health agencies provided links to schools in their communities, took the lead in implementing school-based immunization programs, and provided health education materials. MCOs contributed financial support necessary for the project. The final cost per fully vaccinated student, not taking into account the work group's planning and coordination time, was little more than the catalog price of the vaccine alone.
Managed care organizations face challenges that complicate their participation and funding of school-based vaccinations: 1) Limited data on health plans of participating students complicate allocation of costs to each MCO; 2) Double-paying occurs for MCOs paying clinics a monthly, per-member rate that already includes adolescent immunizations; 3) When schools provide adolescent immunizations, MCOs lose the "hook" that draws adolescents to clinics for comprehensive health services.
When self-consenting is permitted, schools can achieve a high consent and completion rates for multi-dose adolescent immunizations such as hepatitis B. At the same time, MCOs have the responsibility to provide members with comprehensive care and should continue to examine both internal modifications and external partnerships as opportunities to improve their services to adolescents.  相似文献   
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BACKGROUND: Elevated cortisol levels might account for the reduction in central serotonin 1A (5-hydroxytryptamine [5-HT](1A)) receptor binding and function observed in patients with major depression. We tested this hypothesis by studying the effect of acute administration of hydrocortisone on 5-HT(1A) receptor binding potential (BP) in subjects recovered from depression. METHODS: We studied 14 subjects (8 male, 6 female) who had recovered from at least two episodes of major depression and had been euthymic and drug free for at least 6 months. Serotonin 1A receptor BP was measured by [(11)C]WAY-100635 in conjunction with positron emission tomography. Subjects were tested on two occasions in a double-blind, random-order, crossover design after administration of either hydrocortisone (100 mg orally) or placebo 12 hours previously. Positron emission tomography scans were analyzed with a region of interest analysis. RESULTS: Hydrocortisone treatment did not decrease 5-HT(1A) receptor BP either in the hippocampus, which was our a priori hypothesis, or in other cortical 5-HT(1A) regions; however, female subjects had a higher 5-HT(1A) receptor BP in certain brain areas compared with male subjects. CONCLUSIONS: These data are consistent with an earlier study in healthy volunteers and do not support the proposal that decreased 5-HT(1A) receptor BP in patients with acute major depression is a consequence of cortisol hypersecretion.  相似文献   
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This study compares the effects of the cancer experience on various aspects of marital and sexual functioning (e.g., communication, emotional support, body image, sexual satisfaction and frequency) for two groups of long-term cancer survivors (testicular cancer and Hodgkin's disease) and their spouses. Comparisons between the two patient groups showed significantly more survivors of Hodgkin's disease than testicular cancer reporting the emergence of special issues and changes in the marital relationship. No differences emerged between the spouse groups on sexual functioning variables; however, spouses of survivors of Hodgkin's disease were more likely than spouses of survivors of testicular cancer to report the development of special issues and communication difficulties. A substantial proportion of both survivor groups disclosed negative changes in body image and sexual frequency. Majorities of both survivors and spouses acknowledged that the illness had drawn them closer together. When representative marital/sexual functioning variables were used to predict Family Environment Scale (FES) scores for survivors and for spouses, changes in the spouse's importance, influence of the illness on the relationship, and changes in sexual frequency emerged as significant predictors. The clinical significance of long-term changes in marital and sexual functioning for the couple and the need for therapeutic interventions are discussed.  相似文献   
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Mountain Fire     
Southgate  M. Therese 《JAMA》2003,289(24):3211
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Southgate  M. Therese 《JAMA》2005,293(18):2191
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