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Objective: To study the insulin-like growth factor-1 (IGF-1) axis in hirsute women.

Design: Controlled clinical study.

Setting: Tertiary care institutional hospital.

Patient(s): Forty hirsute women and 17 women with normal menstrual cycles.

Intervention(s): Basal and ACTH-stimulated samples were obtained, and sampling was repeated 1 (gonadal stimulation) and 21 (gonadal suppression) days after a single 3.75-mg IM dose of triptorelin. Controls did not receive triptorelin for ethical reasons.

Main Outcome Measure(s): Serum GH, IGF-1, IGF-binding protein-3 (IGFBP-3), insulin, glucose, total testosterone, sex hormone-binding globulin, E2, and gonadotropin levels. Basal and ACTH-stimulated steroid precursors were measured.

Result(s): Patients with idiopathic hirsutism were identified by normal serum androgen levels (n = 17). Those with functional ovarian hyperandrogenism (n = 15) were identified by an increase in the serum testosterone level that normalized during gonadal suppression, whereas those with functional adrenal hyperandrogenism (n = 8) were identified by an initial increase in the testosterone level that persisted during gonadal suppression. The adrenal hyperandrogenism group had increased IGF-1 levels compared with the control, idiopathic hirsutism, and ovarian hyperandrogenism groups. Patients with ovarian hyperandrogenism had normal IGF-1 concentrations, but their IGFBP-3 concentrations were lower than those of controls. No differences were observed in GH levels between any of the groups. These results persisted when the influence of age was corrected for.

Conclusion(s): The IGF-1 axis appears to be involved in the pathogenesis of hyperandrogenism, especially in patients with adrenal hyperandrogenism, who have a clear increase in IGF-1 levels. Moreover, patients with ovarian hirsutism have decreased IGFBP-3 concentrations, which might enhance IGF-1 bioavailability.  相似文献   

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Development of left ventricular pseudoaneurysm is a rare complication of mitral valve surgery and requires urgent surgical intervention. We describe a case of pseudoaneurysm of membranous septum following repeat mitral valve replacement with the use of multimodality imaging.  相似文献   
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Recently, it has been suggested that tranexamic acid should be administered only in those patients with hyperfibrinolysis determined using viscoelastic assays, as severely injured patients may present with fibrinolytic shutdown. However the last European guidelines on management of major bleeding and coagulopathy following trauma endorse the use of tranexamic acid to the trauma patient who is bleeding or at risk of significant hemorrhage as soon as possible without waiting for viscoelastic results. We present a severely blunt trauma patient treated with on-scene administration of tranexamic acid that developed immediate pulmonary embolism.  相似文献   
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Over the last few decades, rising greenhouse gas emissions have promoted poleward expansion of the large-scale atmospheric Hadley circulation that dominates the Tropics, thereby affecting behavior of the Intertropical Convergence Zone (ITCZ) and North Atlantic Oscillation (NAO). Expression of these changes in tropical marine ecosystems is poorly understood because of sparse observational datasets. We link contemporary ecological changes in the southern Caribbean Sea to global climate change indices. Monthly observations from the CARIACO Ocean Time-Series between 1996 and 2010 document significant decadal scale trends, including a net sea surface temperature (SST) rise of ∼1.0 ± 0.14 °C (±SE), intensified stratification, reduced delivery of upwelled nutrients to surface waters, and diminished phytoplankton bloom intensities evident as overall declines in chlorophyll a concentrations (ΔChla = −2.8 ± 0.5%⋅y−1) and net primary production (ΔNPP = −1.5 ± 0.3%⋅y−1). Additionally, phytoplankton taxon dominance shifted from diatoms, dinoflagellates, and coccolithophorids to smaller taxa after 2004, whereas mesozooplankton biomass increased and commercial landings of planktivorous sardines collapsed. Collectively, our results reveal an ecological state change in this planktonic system. The weakening trend in Trade Winds (−1.9 ± 0.3%⋅y−1) and dependent local variables are largely explained by trends in two climatic indices, namely the northward migration of the Azores High pressure center (descending branch of Hadley cell) by 1.12 ± 0.42°N latitude and the northeasterly progression of the ITCZ Atlantic centroid (ascending branch of Hadley cell), the March position of which shifted by about 800 km between 1996 and 2009.  相似文献   
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Since the outcomes of lung transplants are still poorer than those obtained with others, such as heart, kidney or liver transplants, the challenge for medicine remains focused on prolonging functional graft survival. The procedure triggers significant post-surgical physiopathological changes in the lung parenchyma, the rib cage, the airways and pulmonary circulation. The patient is exposed to risks that must be identified and controlled, such as complications fully or partially attributable to immunosuppressive treatment, including cardiovascular disease, tumors and infections and, of course, chronic graft dysfunction.  相似文献   
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