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51.
Diabetes is a global epidemic affecting individuals of all socioeconomic backgrounds. Despite intensive efforts, morbidity and mortality secondary to the micro- and macrovascular complications remain unacceptably high. As a result, the use of imaging modalities to determine the underlying pathophysiology, early onset of complications, and disease progression has become an integral component of the management of such individuals. Echocardiography, stress echocardiography, and nuclear imaging have been the mainstay of noninvasive cardiovascular imaging tools to detect myocardial ischemia, but newer modalities such as cardiac MRI, cardiac CT, and PET imaging provide incremental information not available with standard imaging. While vascular imaging to detect cerebrovascular and peripheral arterial disease non-invasively has traditionally used ultrasound, CT- and MRI-based techniques are increasingly being employed. In this review, we will provide an outline of recent studies utilizing non-invasive imaging techniques to assist in disease diagnosis as well as monitoring disease progression. In addition, we will review the evidence for newer modalities such as MR spectroscopy, 3D intravascular ultrasound, and optical coherence tomography that provide exquisite detail of metabolic function and coronary anatomy not available with standard imaging, but that have not yet become mainstream. 相似文献
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Zhang J Minary P Levitt M 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(25):9845-9850
The method presented here refines molecular conformations directly against projections of single particles measured by electron microscopy. By optimizing the orientation of the projection at the same time as the conformation, the method is well-suited to two-dimensional class averages from cryoelectron microscopy. Such direct use of two-dimensional images circumvents the need for a three-dimensional density map, which may be difficult to reconstruct from projections due to structural heterogeneity or preferred orientations of the sample on the grid. Our refinement protocol exploits Natural Move Monte Carlo to model a macromolecule as a small number of segments connected by flexible loops, on multiple scales. After tests on artificial data from lysozyme, we applied the method to the Methonococcus maripaludis chaperonin. We successfully refined its conformation from a closed-state initial model to an open-state final model using just one class-averaged projection. We also used Natural Moves to iteratively refine against heterogeneous projection images of Methonococcus maripaludis chaperonin in a mix of open and closed states. Our results suggest a general method for electron microscopy refinement specially suited to macromolecules with significant conformational flexibility. The algorithm is available in the program Methodologies for Optimization and Sampling In Computational Studies. 相似文献
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Foreign accent syndrome (FAS) is a rare disorder characterized by the emergence of a perceived foreign accent following brain damage. The symptomotology, functional bases, and neural substrates of this disorder are still being elucidated. In this case study, acoustic analyses were performed on the speech of a 46‐year old monolingual female who presented with FAS of unknown aetiology. The patient had a pseudo‐accent frequently described as ‘Swedish’ or ‘Eastern European’. Stop consonant VOT, consonant burst spectra and duration, vowel durations, formant frequencies, and trajectories were analysed, along with prosodic cues for lexical stress assignment and sentence‐level intonation. Results indicated VOT values were generally preserved, while there was a strong tendency to realize the English alveolar flap as a full stop, and to produce flaps that had greater‐than‐normal closure durations. The spectral properties of the patient's vowels resembled those of normal talkers (with the possible exceptions of decreased F1 values for /i/ and slight differences in formant dynamics for /u/, /o/, /i/, and /?/). However, vowel durations were relatively long, contributing to exaggerated tense/lax contrasts. Token‐to‐token variability in vowel production was slightly higher than normal for duration, but not for formant frequency values. Lexical stress assignment was inaccurate and highly variable (with similar problems noted for non‐speech materials), and sentence level intonation showed occasional deviations from typical American English patterns. For this patient, an underlying timing/rhythm difficulty appeared responsible for the range of segmental and suprasegmental changes leading to the impression of a foreign accent. 相似文献
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Jessica v. Stringer Heidi M. Levitt Jeffrey S. Berman Susan S. Mathews 《Psychotherapy research》2013,23(5):495-510
Abstract Fifty-two psychotherapy sessions were coded for silences that reflect processes of client disengagement (e.g., withdrawal, resistance). The study examined the presence of these silences and clients' reports of in-session emotion and symptom change. Results indicated that disengagement predicted poorer proximal and distal outcome as measured by the Beck Depression Inventory for Primary Care (BDI-PC) and poorer proximal outcome on the Symptom Checklist-5, but it was not significantly predictive of Outcome Questionnaire-45 scores. Interitem analyses revealed that disengagement had a significant proximal effect on depressive mood and negative self-evaluative items assessed by the BDI-PC, but across time these effects were sustained for the negative self-evaluative items only. 相似文献
59.
The genuine prevalence of personality disorders among those with eating disorders is unknown. However, in this paper, we summarize the existing data, with careful acknowledgment of our approach to interpretation as well as the limitations of previous studies. Our findings indicate that obsessive-compulsive personality is the most common personality disorder in restricting-type anorexia nervosa, while borderline personality is the most common personality disorder in binge-eating/purging type anorexia nervosa. Borderline personality is the most common personality disorder in bulimia nervosa, as well. In those with binge eating disorder, obsessive-compulsive personality is the most common personality disorder although, compared with the preceding eating disorder diagnoses, there are broader clusters of personality disorders represented in this group. We discuss the implications of these findings. 相似文献
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