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Most vertebral fractures (VFs) are asymptomatic and incidentally found on X-rays. The effects of acromegaly on bone mineral density (BMD) are still controversial, and the prevalence of VFs in this specific population remains uncertain. The objective of this study was to assess VFs in acromegaly through vertebral fracture assessment (VFA) by dual-energy X-ray absorptiometry (DXA). Seventy-five acromegalic patients from the same center (53 female; age: 48.9 ± 14.5 yr) were enrolled in this study. None of them referred previous fragility fracture. They were divided according to the presence or absence of moderate or severe VFs on VFA, a densitometric spine imaging. Age, gender, estimated duration of disease, insulin-like growth factor I levels, disease control and gonadal status, as well as BMD and body composition (analyzed by DXA) were compared between these 2 groups. A prevalence of 10.6% of clinically unapparent VFs was observed. Eight patients had 13 moderate or severe VFs, and only one of them had osteoporosis at densitometry. There was a trend to longer duration of acromegaly before diagnosis, higher prevalence of hypogonadism, and higher BMD Z-score at lumbar spine and femoral neck in fractured patients, without reaching statistical significance. There is a significant prevalence of moderate and severe VFs in acromegalic patients, independently of BMD. More longitudinal and controlled studies are needed to recommend the use of VFA in all acromegalic patients submitted to DXA scan. VFA is simple, practical, uses low radiation, and may provide important information in the management of acromegaly.  相似文献   
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Magalhães  J.  Ventura  N.  Lamback  E. B.  Da Silva  D.  Camacho  A. H.  Chimelli  L.  Gadelha  M. R.  Kasuki  L. 《Pituitary》2022,25(3):433-443
Pituitary - To evaluate the efficacy and safety of oral estrogen therapy in female patients of childbearing age with uncontrolled acromegaly and to verify the significance of the presence of...  相似文献   
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Sport Sciences for Health - To investigate the hemodynamic responses, especially HPE following different resistance exercises RE protocols in young adult subjects. Eighty-nine men...  相似文献   
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BackgroundOur previous studies showed increased angiotensin I-converting enzyme (ACE) activity in chronic schizophrenia patients compared with healthy control (HC) volunteers, and the relevance of combining ACE genotype and activity for predicting schizophrenia was suggested.MethodsACE activity was measured in plasma of ACE insertion/deletion (I/D) genotyped HC volunteers (n = 53) and antipsychotic-naïve first-episode psychosis (FEP) patients (n = 45) assessed at baseline (FEB-B) and also after 2 months (FEP-2M) of treatment with the atypical antipsychotic risperidone.ResultsACE activity measurements showed significant differences among HC, FEP-B, and FEP-2M groups (F = 5.356, df = 2, P = .005) as well as between HC and FEP-2M (post-hoc Tukey’s multiple comparisons test, P = .004). No correlation was observed for ACE activity increases and symptom severity reductions in FEP as assessed by total Positive and Negative Syndrome Scale (r = −0.131, P = .434). FEP subgrouped by ACE I/D genotype showed significant ACE activity increases, mainly in the DD genotype subgroup. No correlation between ACE activity and age was observed in FEP or HC groups separately (r = 0.210, P = .392), but ACE activity level differences observed between these groups were influenced by age.ConclusionsThe importance of measuring the ACE activity in blood plasma, associated with ACE I/D genotyping to support the follow-up of FEP patients, did not show correlation with general symptom amelioration in the present study. However, new insights into the influence of age and I/D genotype for ACE activity changes in FEP individuals upon treatment was demonstrated.  相似文献   
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Sawada  Y; Fass  DN; Katzmann  JA; Bahn  RC; Bowie  EJ 《Blood》1986,67(5):1229-1239
Hemostatic plug (HP) formation was investigated in the ear bleeding time incision in normal and von Willebrand pigs. HP volume was calculated by integrating the areas of serial sections. In normal pigs (n = 11), platelets immediately formed a layer on the surface of the cut channel. Platelet aggregates formed at the ends of transected vessels and gradually enlarged. Finally, all transected vessels were occluded by HP and bleeding stopped. In contrast, large HPs were formed in the incision in von Willebrand's disease (vWD) pigs (n = 4); these HPs did not cover the ends of the transected vessels, which continued to bleed, allowing the formation of large hemostatically ineffective platelet aggregates in the incision. Canals traversed these HPs, and bleeding from the open vessels may have continued through them. After infusion of cryoprecipitate into a vWD pig, the bleeding time shortened, and the morphological findings of the HPs were similar to those of normal pigs. In normal pigs (n = 3) infused with an anti- Willebrand factor monoclonal antibody, which prolonged the bleeding time, a large HP formed in the incision, similar to that observed in the vWD pig. The volume of the normal and vWD HPs increased with time. These in vivo findings suggest that Willebrand factor is involved in the localization of the HP to the damaged vessel and may also play a role in platelet-platelet interaction. A computerized morphometric technique was used for measuring the volume of the hemostatic plugs and the distance of sequential points on the perimeter of the HP from the center of selected bleeding vessels.  相似文献   
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