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The in vitro steroidogenic capacity of the gonadal tissue in the protandrous Rhabdosargus sarba was studied. Testicular and ovarian tissues from various sexual phases were used either separately or combined. With progesterone as precursor, high yield of 5 beta-reduced metabolites, and no 11-ketotestosterone or 11 beta-hydroxytestosterone were found. The production of 5 beta-pregnan-3 alpha-ol-20-one and 5 beta-pregnane-3,20-dione was very high in incubations with testicular tissue from intersexes or males and was low in those with ovarian tissue only. The production of 17 alpha-hydroxyprogesterone was high in the female but was low in other sexual phases. With testosterone as precursor, 11-ketotestoterone and 11 beta-hydroxytestosterone were identified. The latter was the most abundant and prominent polar steroid in all incubations. 5 beta-Reductase activity was high in the male and relatively low in the female. 5 alpha-Reduced products, however, were absent. There was an increase in the production of androstenedione as the animal underwent sex reversal. The significance of this change in steroidogenesis in this protandrous fish is at present under investigation. Experimental results also indicated that in the intersexual gonad there may be interaction between the testicular component and the ovarian component in steroidgenesis.  相似文献   
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BackgroundTools for advance care planning (ACP) are advocated to help ensure patient values guide healthcare decisions. Evaluation of the effect of tools introduced to patients in clinical settings is needed.ObjectiveTo evaluate the effect of the Canadian Speak Up Campaign tools on engagement in advance care planning (ACP), with patients attending outpatient clinics.Patient involvement: Patients were not involved in the problem definition or solution selection in this study but members of the public were involved in development of tools. The measurement of impacts involved patients.MethodsThis was a prospective pre-post study in 15 primary care and two outpatient cancer clinics. The outcome was scores on an Advance Care Planning Engagement Survey measuring Behavior Change Process on 5-point scales and Actions (0?21-point scale) administered before and six weeks after using a tool, with reminders at two or four weeks.Results177 of 220 patients (81%) completed the study (mean 68 years of age, 16% had cancer). Mean Behavior Change Process scores were 2.9 at baseline and 3.5 at follow-up (mean change 0.6, 95% confidence interval 0.5 to 0.7; large effect size of 0.8). Mean Action Measure score was 3.7 at baseline and 4.8 at follow-up (mean change 1.1, 95% confidence interval 0.6–1.5; small effect size of 0.2).Practical valuePublicly available ACP tools may have utility in clinical settings to initiate ACP among patients. More time and motivation may be required to stimulate changes in patient behaviors related to ACP.  相似文献   
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ObjectiveBilateral oophorectomy leads to reduced bone mineral density (BMD), and reduced BMD is associated with increased marrow fat and reduced marrow perfusion. Purpose of this study was to investigate how soon these changes occur following surgical oophorectomy.ResultsReduced BMD, increased marrow FF, and reduced marrow perfusion occurred synchronously post-oophorectomy. There was a sharp decrease of 12.5 ± 7.2% in BMD (n = 6), a sharp increase of 92.2 ± 46.3% (n = 6) in FF, a sharp decrease of 23.6 ± 3.9% in maximum contrast enhancement (n = 5), and of 45.4 ± 7.7% for enhancement slope (n = 5) during the initial 3 months post surgery. BMD and marrow perfusion continued to decrease, and marrow FF continued to increase at a slower rate during the following 18 months. Friedman test showed a significant trend for these changes (p < 0.05).ConclusionBilateral oophorectomy leads to a rapid decrease in lumbar BMD, an increase in marrow fat content, and a decrease in marrow blood perfusion.  相似文献   
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