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71.
Research questionWhat are the views and emotional reactions of patients towards the suspension of fertility treatment during the COVID-19 pandemic, and what are the factors affecting their psychological distress?DesignA cross-sectional study conducted in an academic fertility centre. Online questionnaires were distributed between 18 April 2020 and 23 April 2020 to patients whose treatment cycle had been postponed or discontinued. The outcome measures included agreement with the reproductive society guidelines to postpone treatments; willingness to resume treatments, given the choice; patients’ emotional reactions; and psychological distress level, measured by the Mental Health Inventory validated scale. A multivariate linear regression was conducted to identify factors associated with psychological distress.ResultsBecause of the small number of male respondents, only women were included in the analysis (n = 181). Forty-three per cent expressed disagreement with the guidelines and 82% were willing to resume treatments, given the choice. Sadness and anxiety were the most common emotional reactions expressed towards the guidelines. In the multivariate analysis, COVID-19-related anxiety (B = 0.145, P = 0.04) and disagreement with treatment suspension (B = –0.44, P = 0.001) were found to be significantly associated with patients' psychological distress. Background characteristics of patients did not contribute significantly to their distress.ConclusionsSuspension of fertility treatment during the initial phase of the COVID-19 pandemic was associated with patients' negative emotional reactions. Anxiety related to COVID-19 and disagreement with treatment suspension were found to be significantly associated with psychological distress among women undergoing fertility treatment, regardless of their background characteristics. Our findings suggest the need to monitor the mental health of patients and provide psychological support should a shutdown of fertility care re-occur.  相似文献   
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PURPOSE: To evaluate the usefulness of thoracic computed tomography (CT) in the pre-lung transplantation examination of patients with cystic fibrosis (CF). MATERIALS AND METHODS: Fifty-six patients (age range, 12-42 years) with CF were evaluated for possible lung transplantation from 1991 to 1997. Twenty-six of these patients underwent bilateral lung transplantation, 19 were awaiting transplantation at the time of the study, seven died before transplantation, and four were excluded for psychosocial concerns. Preoperative chest radiographic and CT findings were reviewed and correlated with clinical, operative, and pathology records. RESULTS: In seven patients, discrete, 1-2-cm pulmonary nodules were detected at CT. Five of these patients underwent transplantation; the nodules were found to be mucous impactions. No malignancy was found in any of the patients who underwent transplantation. Pretransplantation sputum cultures grew Aspergillus fumigatus in seven patients, none of whom had radiologic findings suggestive of Aspergillus infection. Radiographic or CT findings were suggestive of mycetoma in five cases, but no such tumors were found at transplantation. The accuracies of chest radiography and CT for the detection of pleural disease in 48 hemithoraces were 81% (n = 39) and 69% (n = 33), respectively. The radiologic findings of pleural thickening did not influence the surgical approach in any patient. CONCLUSION: Thoracic CT has little utility in the routine pre-lung transplantation examination of patients with CF.  相似文献   
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Electrical stimulation is emerging as a viable alternative for patients with epilepsy whose seizures are not alleviated by drugs or surgery. Its attractions are temporal and spatial specificity of action, flexibility of waveform parameters and timing, and the perception that its effects are reversible unlike resective surgery. However, despite significant advances in our understanding of mechanisms of neural electrical stimulation, clinical electrotherapy for seizures relies heavily on empirical tuning of parameters and protocols. We highlight concurrent treatment goals with potentially conflicting design constraints that must be resolved when formulating rational strategies for epilepsy electrotherapy, namely, seizure reduction versus cognitive impairment, stimulation efficacy versus tissue safety, and mechanistic insight versus clinical pragmatism. First, treatment markers, objectives, and metrics relevant to electrical stimulation for epilepsy are discussed from a clinical perspective. Then the experimental perspective is presented, with the biophysical mechanisms and modalities of open-loop electrical stimulation, and the potential benefits of closed-loop control for epilepsy.  相似文献   
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Background

The attainment of upright posture, with its requisite lumbar lordosis, was a major turning point in human evolution. Nonhuman primates have small lordosis angles, whereas the human spine exhibits distinct lumbar lordosis (30°–80°). We assume the lumbar spine of the pronograde ancestors of modern humans was like those of extant nonhuman primates, but which spinal components changed in the transition from small lordosis angles to large ones is not fully understood.

Questions/Purposes

We wished to determine the relative contribution of vertebral bodies and intervertebral discs to lordosis angles in extant primates and humans.

Methods

We measured the lordosis, intervertebral disc, and vertebral body angles of 100 modern humans (orthograde primates) and 56 macaques (pronograde primates) on lateral radiographs of the lumbar spine (humans–standing, macaques–side-lying).

Results

The humans exhibited larger lordosis angles (51°) and vertebral body wedging (5°) than did the macaques (15° and ?25°, respectively). The differences in wedging of the intervertebral discs, however, were much less pronounced (46° versus 40°).

Conclusions

These observations suggest the transition from pronograde to orthograde posture (ie, the lordosis angle) resulted mainly from an increase in vertebral body wedging and only in small part from the increase in wedging of the intervertebral discs.  相似文献   
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We calculated the electric fields induced in the brain during transcranial current stimulation (TCS) using a finite-element concentric spheres human head model. A range of disc electrode configurations were simulated: (1) distant-bipolar; (2) adjacent-bipolar; (3) tripolar; and three ring designs, (4) belt, (5) concentric ring, and (6) double concentric ring. We compared the focality of each configuration targeting cortical structures oriented normal to the surface ('surface-radial' and 'cross-section radial'), cortical structures oriented along the brain surface ('surface-tangential' and 'cross-section tangential') and non-oriented cortical surface structures ('surface-magnitude' and 'cross-section magnitude'). For surface-radial fields, we further considered the 'polarity' of modulation (e.g. superficial cortical neuron soma hyper/depolarizing). The distant-bipolar configuration, which is comparable with commonly used TCS protocols, resulted in diffuse (un-focal) modulation with bi-directional radial modulation under each electrode and tangential modulation between electrodes. Increasing the proximity of the two electrodes (adjacent-bipolar electrode configuration) increased focality, at the cost of more surface current. At similar electrode distances, the tripolar-electrodes configuration produced comparable peak focality, but reduced radial bi-directionality. The concentric-ring configuration resulted in the highest spatial focality and uni-directional radial modulation, at the expense of increased total surface current. Changing ring dimensions, or use of two concentric rings, allow titration of this balance. The concentric-ring design may thus provide an optimized configuration for targeted modulation of superficial cortical neurons.  相似文献   
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