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81.
The lateral support of the vaginal wall depends on the integrity of the paravaginal section of the visceral pelvic fascia, levator ani, and their connection. Various defects of the muscle and fascia can result in identical clinical findings—ie, the descent of the lateral vaginal sulcus. In this study, we created a realistic scheme for classifying paravaginal defects, based on the complex relationship of the pelvic fascia with the levator ani. Surgical observations, cadaver examinations, and a complex magnetic resonance imaging (MRI)‐based 3‐dimensional (3D) model were used to analyze the spatial relationships of normal and defective anatomy of the female pelvic floor. Descent of the lateral vaginal sulcus can result from a defect in the paravaginal visceral pelvic fascia, levator ani, or both. The fascial defect can be partial or complete, and the muscle defect can vary in location. A detailed illustrated classification is presented. We present a new model of the pathology that underlies a common clinical finding. Clin. Anat. 29:524–529, 2016. © 2016 Wiley Periodicals, Inc.  相似文献   
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During the last 2 decades, the treatment of hyperglycemia in critically ill patients has become one of the most discussed topics in the intensive medicine field. The initial data suggesting significant benefit of normalization of blood glucose levels in critically ill patients using intensive intravenous insulin therapy have been challenged or even neglected by some later studies. At the moment, the need for glucose control in critically ill patients is generally accepted yet the target glucose values are still the subject of ongoing debates. In this review, we summarize the current data on the benefits and risks of tight glucose control in critically ill patients focusing on the novel technological approaches including continuous glucose monitoring and its combination with computer-based algorithms that might help to overcome some of the hurdles of tight glucose control. Since increased risk of hypoglycemia appears to be the major obstacle of tight glucose control, we try to put forward novel approaches that may help to achieve optimal glucose control with low risk of hypoglycemia. If such approaches can be implemented in real-world practice the entire concept of tight glucose control may need to be revisited.  相似文献   
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Medical resource allocation is a controversial topic, because in the end it prioritises some peoples’ medical problems over those of others. This is less controversial when there is a clear clinical reason for such a prioritisation, but when such a reason is not available people might perceive it as deeming certain individuals more important than others. This article looks at the role of social utility in medical resource allocation, in a situation where the clinical outcome would be identical if either person received the treatment. This situation is explored with a focus on the United Kingdom, but its conclusions have wider applications to any system where healthcare is tax-payer funded. The article proposes an experience adjusted life years system, and discusses its strengths and weaknesses.  相似文献   
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Objectives: The purpose of this study was to assess the relationship between apolipoprotein E (APOE), life events and engagement, and subjective well-being (as measured by positive and negative affect) among centenarians. Based on the life stress paradigm, we predicted that higher levels of stress would allow APOE to influence positive and negative affect.

Method: 196 centenarians and near-centenarians (98 years and older) of the Georgia Centenarian Study participated in this research. The APOE, positive and negative affect, the number of recent (last 2 years) and lifelong (more than 20 years prior to testing) events, as well as a number of life engagement tasks were assessed.

Results: Results suggested that centenarians carrying the APOE ?4 allele rated lower in positive affect, the number of lifelong events, and in engaged lifestyle, when compared to centenarians without the APOE ?4 allele (t = 3.43, p < .01; t = 3.19, p < .01; and t = 2.33, p < .05, respectively). Blockwise multiple regressions indicated that the APOE ?4 predicted positive but not negative affect after controlling for demographics. Gene–environment interactions were obtained for the APOE ?4 and lifelong events, suggesting that carriers of the APOE ?4 allele had higher scores of negative affect after having experienced more events, whereas noncarriers had reduced negative affect levels after having experienced more events.

Conclusion: APOE ?4 is directly related to positive affect and is related to negative affect in interaction with life events.  相似文献   
86.
Patients with congenital heart disease (CHD) have been surviving late into adulthood, with atrial arrhythmias being the most common long-term complication. In recent reports, atrial fibrillation (AF) tended to be the most common form of arrhythmias among groups of patients with adult CHD (ACHD) older than 50 years of age. When compared with their adult counterparts without CHD, AF in patients with ACHD has been characterized by a higher incidence and prevalence, younger age of onset, and a greater risk of progression to persistent AF. Risk factors for the development of AF are not well known but include older age, left atrial dilation, systemic hypertension, and multiple cardiac surgeries. Data on management options such as optimal antiarrhythmic drug therapy, indications for anticoagulation, and efficacy and safety of catheter ablation are limited. There is a crucial need for further research exploring management, prevention, and monitoring strategies for the growing ACHD patient population with AF. This report will provide a contemporary review of the epidemiology, pathophysiology, and management options for AF in this complex patient population.  相似文献   
87.
The primary aim of this work is to propose and investigate the effectiveness of a novel unsupervised tissue clustering and classification algorithm for diffusion tensor MRI (DTI) data. The proposed algorithm utilizes information about the degree of homogeneity of the distribution of diffusion tensors within voxels. We adapt frameworks proposed by Hext and Snedecor, where the null hypothesis of diffusion tensors belonging to the same distribution is assessed by an F‐test. Tissue type is classified according to one of the four possible diffusion models, the assignment of which is determined by a parsimonious model selection framework based on Schwarz Criterion. Both numerical phantoms and diffusion‐weighted imaging (DWI) data obtained from excised rat and pig spinal cords are used to test and validate these tissue clustering and classification approaches. The unsupervised clustering method effectively identifies distinct regions of interest (ROIs) in phantoms and real experimental DTI data. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
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Acetylcholine-binding proteins (AChBPs) from mollusks are suitable structural and functional surrogates of the nicotinic acetylcholine receptors when combined with transmembrane spans of the nicotinic receptor. These proteins assemble as a pentamer with identical ACh binding sites at the subunit interfaces and show ligand specificities resembling those of the nicotinic receptor for agonists and antagonists. A subset of ligands, termed the neonicotinoids, exhibit specificity for insect nicotinic receptors and selective toxicity as insecticides. AChBPs are of neither mammalian nor insect origin and exhibit a distinctive pattern of selectivity for the neonicotinoid ligands. We define here the binding orientation and determinants of differential molecular recognition for the neonicotinoids and classical nicotinoids by estimates of kinetic and equilibrium binding parameters and crystallographic analysis. Neonicotinoid complex formation is rapid and accompanied by quenching of the AChBP tryptophan fluorescence. Comparisons of the neonicotinoids imidacloprid and thiacloprid in the binding site from Aplysia californica AChBP at 2.48 and 1.94 A in resolution reveal a single conformation of the bound ligands with four of the five sites occupied in the pentameric crystal structure. The neonicotinoid electronegative pharmacophore is nestled in an inverted direction compared with the nicotinoid cationic functionality at the subunit interfacial binding pocket. Characteristic of several agonists, loop C largely envelops the ligand, positioning aromatic side chains to interact optimally with conjugated and hydrophobic regions of the neonicotinoid. This template defines the association of interacting amino acids and their energetic contributions to the distinctive interactions of neonicotinoids.  相似文献   
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