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101.
Although the terms "metabolic memory" and "legacy effect" have been used to describe the prolonged benefits of good blood glucose control, the former is now recognized as a phenomenon related to the prolonged harm produced mainly by hyperglycemia. At least three randomized clinical trials (Diabetes Control and Complications Trial in type 1 diabetes, United Kingdom Prospective Diabetes Study and Steno-2 in type 2 diabetes) have demonstrated that patients treated intensively for a period of time have a lower risk of micro- and macrovascular complications that persists during subsequent follow-up, even after their tight control has relented and the levels of glycated hemoglobin in the conventionally treated group improve. The mechanisms are not fully understood but most probably relate to the physiopathology of vascular complications of diabetes, and in recent years a unifying theory has been emerging to understand them. The excess superoxide anion produced by the mitochondria in response to hyperglycemia leads through disturbances at the nuclear level to the accumulation of potentially harmful substances such as advanced glycated end-products, protein kinase C, and nuclear factor κB, which are directly implicated in the development of vascular complications in diabetes. These adverse effects are not reversed when the high blood glucose is corrected, and some may be permanent because of epigenetic changes. Some antidiabetes drugs and antioxidant substances have produced partial reversibility of the mechanisms involved in the metabolic memory at the experimental level, but probably the best strategy is to optimize the metabolic control as early as possible, even before diabetes is diagnosed.  相似文献   
102.

Introduction and hypothesis

Benign joint hypermobility syndrome may be a risk factor for pelvic floor disorders. It is unknown whether hypermobility impacts the progress of childbirth, a known risk factor for pelvic floor disorders. Our objective was to investigate the association between joint hypermobility syndrome, obstetrical outcomes, and pelvic floor disorders. Our hypotheses were: (1) women with joint hypermobility are less likely to experience operative delivery and prolonged second-stage labor; and (2) pelvic floor disorders are associated with benign hypermobility syndrome, controlling for obstetrical history.

Methods

Joint hypermobility was measured in 587 parous women (participants in a longitudinal cohort study of pelvic floor disorders after childbirth). Their obstetrical histories were obtained from review of hospital records. Pelvic floor disorders were assessed using validated questionnaires and a structured examination for prolapse. Joint hypermobility and pelvic floor disorders were evaluated at enrollment (5–10 years after first delivery). We compared obstetrical outcomes and pelvic floor disorders between women with and without joint hypermobility, defined as a Beighton score ≥4.

Results

Hypermobility was diagnosed in 46 women (7.8 %) and was associated with decreased odds of cesarean after complete cervical dilation or operative vaginal delivery [odds ratio (OR)?=?0.51; 95 % confidence interval (CI):0.27–0.95]. Anal sphincter laceration was unlikely to occur in women with hypermobility (OR?=?0.19; 95 % CI 0.04–0.80). However, hypermobility was not associated with any pelvic floor disorder considered.

Conclusions

Benign joint hypermobility syndrome may facilitate spontaneous vaginal birth but does not appear to be a risk factor for pelvic floor disorders in the first decade after childbirth.  相似文献   
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This study was conducted in order to define the diagnostic performance of CT angiography for vascular injuries compared with angiography in patients with neck trauma. CT angiography is the cornerstone of diagnosis for hemodynamically stable patients with wounds suspicious of vascular trauma in the limbs, chest, or abdomen. Available evidence for the use of CT angiography in neck vascular trauma comes from small case series and few randomized controlled trials, and high-quality information does not exist regarding its performance. A protocol using the recommendations of the Cochrane Collaboration was designed. A systematic search of diagnostic studies without limits on language or time was carried out to December 2014. Studies including patients with neck trauma with retrospective or prospective data collection that assessed CT angiography compared with other methods were selected. Methodological quality was assessed using the QUADAS-2 tool. A hierarchical model ROC curve and a bivariate random effects model were used for the pooled analysis. Sixteen studies were selected and reviewed, and nine studies with 693 patients were included in this review. The overall sensitivity was 97 % (95 % CI 0.77–1.00; I 2?=?65.7 % (41.4–90.0)), while the overall specificity was 99 % (95 % CI 0.93–1.00; I 2?=?0). The hierarchic ROC curve showed an area under the curve of 0.99. Publication bias was not identified in this study. CT angiography can be stated as the gold standard for diagnosing vascular injuries in hemodynamically stable patients with neck trauma.  相似文献   
108.
We tested the hypothesis that MELD-XI values correlated with hepatic total fibrosis scores obtained in 70 predominately stable, post-Fontan patients that underwent elective cardiac catheterization. We found a statistically significant correlation between MELD-XI values and total fibrosis scores (p = 0.003). Thus, serial MELD-XI values may be an additional useful clinical parameter for follow-up care in post-Fontan patients.  相似文献   
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Introduction

Although impaired pulmonary function and respiratory sleep disorders are described as responsible for increased mortality in acromegalic patients, little is known about the tracheal abnormalities in this group of patients. Thus, the objectives of this study were to describe the tracheal structural abnormalities and correlate these changes with the respiratory function and clinical data of acromegalic patients.

Material and methods

This is a cross-sectional study that was carried out at two university hospitals. Twenty acromegalic patients underwent spirometry, forced oscillation technique, and computed tomography (CT) assessments. Dyspnea and daytime sleepiness were assessed using the Modified Medical Research Council (MMRC) scale and the Epworth Sleepiness Scale (ESS), respectively. Forty matched subjects served as controls.

Results

The acromegalic patients exhibited larger median ratios between forced expiratory flow and forced inspiratory flow at 50% of the forced vital capacity (FEF50%/FIF50%) (2.05 vs. 1.06, p = 0.0001) compared with healthy volunteers. In the CT analysis, acromegalic patients exhibited larger median differences between their cervical and thoracic tracheal diameters (Δ tracheal diameters) (3 vs. 1 mm; p = 0.003). An association was found between FEF50%/FIF50% and the following variables: mean resistance (Rm), cervical tracheal diameter, and Δ tracheal diameters. Rm also exhibited a negative correlation with cervical tracheal diameter. Neither the MMRC scale nor the ESS exhibited any significant correlation with large airway obstruction (LAO) indices or with the measured tracheal diameters.

Conclusions

Acromegalic patients have tracheal structural abnormalities which are associated with functional indicators of LAO but not with clinical data.  相似文献   
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