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81.
82.
Objective: The Geriatric Anxiety Scale (GAS) is a new self-report screening measure designed for older adults. Due to the burgeoning Iranian population of older adults and the need for validated, culturally-appropriate screening measures for anxiety in Iran, the purposes of the present study were to translate the GAS into Persian and to explore its preliminary psychometric properties.

Method: Iranian older adults (N = 295; M age = 67.0 years) completed the GAS and the Iranian version of the Geriatric Depression Scale (GDS-15).

Results: Cronbach's alpha for the GAS total score and the GAS subscales were excellent (Total score α = .92; Cognitive α = .81; Somatic α = .84; Affective α = .80). As expected, each subscale was significantly positively correlated (all p's < .01) with the other subscales. The subscales share common variance ranging from 42% to 56%. The GAS total score and GAS subscale scores were significantly positively correlated with the GDS-15, with medium effect sizes (GAS Total r = .55; Cognitive r = .51; Somatic r = .50; Affective r = .48). Finally, exploratory and confirmatory factor analyses were conducted to investigate the factor structure of the Persian version of the GAS. Results support a one factor solution (general anxiety) for this Iranian sample.

Conclusion: This study provides preliminary psychometric support for the Persian version of the GAS as a screening measure for anxiety in Iranian older adults, with a one-dimensional factor structure.  相似文献   

83.
Objectives: There is a growing need for evaluation of the results of mental health services and clinical treatment in older people, but evidence for effectiveness is limited in Greece. The Health of the Nations Outcome Scales for Elderly People (HoNOS65+) are promising instruments for the assessment of mental, physical and social health in older persons. They have been translated into the Greek language but have not been validated. The aim was to assess the inter-rater reliability, intraclass correlation, concurrent validity, internal consistency and sensitivity to change of HoNOS65+ in a Greek sample of older people with mental health problems.

Method: Two samples, one of inpatients in a psychiatric hospital and the other of older people living in the community were used. In order to test the extent to which the HoNOS65+ were sensitive to change the first sample was reassessed after two months and the second after three months. For each participant HoNOS65+ were completed by two independent raters, and the clinician rated blindly each participant on the Stockton Geriatric Rating Scale and a scale which measured behavioural, physical, cognitive and emotional status.

Results: In both groups (inpatients n?=?50, community n?=?65), the inter-rater reliability, intraclass correlation and concurrent validity were high while internal consistency of the scales taken together was low. At reassessment in 98 participants, HoNOS65+ showed changes comparable to clinician ratings.

Conclusion: The Greek version of HoNOS65+ can achieve high levels of reliability, validity and sensitivity to change for measuring outcomes in older people with mental health problems.  相似文献   
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85.

Purpose

A new concept of vertebra vectors based on spinal three-dimensional (3D) reconstructions of images from the EOS system, a new low-dose X-ray imaging device, was recently proposed to facilitate interpretation of EOS 3D data, especially with regard to horizontal plane images. This retrospective study was aimed at the evaluation of the spinal layout visualized by EOS 3D and vertebra vectors before and after surgical correction, the comparison of scoliotic spine measurement values based on 3D vertebra vectors with measurements using conventional two-dimensional (2D) methods, and an evaluation of horizontal plane vector parameters for their relationship with the magnitude of scoliotic deformity.

Methods

95 patients with adolescent idiopathic scoliosis operated according to the Cotrel-Dubousset principle were subjected to EOS X-ray examinations pre- and postoperatively, followed by 3D reconstructions and generation of vertebra vectors in a calibrated coordinate system to calculate vector coordinates and parameters, as published earlier. Differences in values of conventional 2D Cobb methods and methods based on vertebra vectors were evaluated by means comparison T test and relationship of corresponding parameters was analysed by bivariate correlation. Relationship of horizontal plane vector parameters with the magnitude of scoliotic deformities and results of surgical correction were analysed by Pearson correlation and linear regression.

Results

In comparison to manual 2D methods, a very close relationship was detectable in vertebra vector-based curvature data for coronal curves (preop r 0.950, postop r 0.935) and thoracic kyphosis (preop r 0.893, postop r 0.896), while the found small difference in L1–L5 lordosis values (preop r 0.763, postop r 0.809) was shown to be strongly related to the magnitude of corresponding L5 wedge. The correlation analysis results revealed strong correlation between the magnitude of scoliosis and the lateral translation of apical vertebra in horizontal plane. The horizontal plane coordinates of the terminal and initial points of apical vertebra vectors represent this (r 0.701; r 0.667). Less strong correlation was detected in the axial rotation of apical vertebras and the magnitudes of the frontal curves (r 0.459).

Conclusions

Vertebra vectors provide a key opportunity to visualize spinal deformities in all three planes simultaneously. Measurement methods based on vertebral vectors proved to be just as accurate and reliable as conventional measurement methods for coronal and sagittal plane parameters. In addition, the horizontal plane display of the curves can be studied using the same vertebra vectors. Based on the vertebra vectors data, during the surgical treatment of spinal deformities, the diminution of the lateral translation of the vertebras seems to be more important in the results of the surgical correction than the correction of the axial rotation.  相似文献   
86.
The role of Bone Tissue Engineering in the field of Regenerative Medicine has been the topic of substantial research over the past two decades. Technological advances have improved orthopaedic implants and surgical techniques for bone reconstruction. However, improvements in surgical techniques to reconstruct bone have been limited by the paucity of autologous materials available and donor site morbidity. Recent advances in the development of biomaterials have provided attractive alternatives to bone grafting expanding the surgical options for restoring the form and function of injured bone. Specifically, novel bioactive (second generation) biomaterials have been developed that are characterised by controlled action and reaction to the host tissue environment, whilst exhibiting controlled chemical breakdown and resorption with an ultimate replacement by regenerating tissue. Future generations of biomaterials (third generation) are designed to be not only osteoconductive but also osteoinductive, i.e. to stimulate regeneration of host tissues by combining tissue engineering and in situ tissue regeneration methods with a focus on novel applications. These techniques will lead to novel possibilities for tissue regeneration and repair. At present, tissue engineered constructs that may find future use as bone grafts for complex skeletal defects, whether from post-traumatic, degenerative, neoplastic or congenital/developmental “origin” require osseous reconstruction to ensure structural and functional integrity. Engineering functional bone using combinations of cells, scaffolds and bioactive factors is a promising strategy and a particular feature for future development in the area of hybrid materials which are able to exhibit suitable biomimetic and mechanical properties. This review will discuss the state of the art in this field and what we can expect from future generations of bone regeneration concepts.  相似文献   
87.
The present study examined lexical representation in early Spanish‐English bilinguals using an unmasked semantic and translation priming paradigm. In Experiment 1, participants were divided into two groups based on performance (more‐balanced bilinguals, MB and less‐balanced bilinguals, LB) on the experimental task. In Experiment 2, four patients with bilingual aphasia (BA) performed the same experiment. Results from both experiments revealed that all groups were more accurate for English targets (S‐E direction) than Spanish targets (S‐E direction). In Experiment 1, semantic priming was observed from English to Spanish in both the LB and MB groups although the effect was greater for the LB group. Further, only the LB group showed priming from Spanish to English. For both normal groups, there was no difference between translation and semantic priming effects. In Experiment 2, patients with bilingual aphasia demonstrated different patterns of activation with no clear trends. Two participants demonstrated greater priming from Spanish to English whereas two participants demonstrated the opposite effect.  相似文献   
88.
89.
The growing fraction (GF) of tumor has been reported as one of the predictive markers of the efficacy of chemotherapeutics. Therefore, a semi-mechanistic model has been developed that describes tumor growth on the basis of cell cycle, allowing the incorporation of the GF of a tumor in pharmacokinetic/pharmacodynamic (PK/PD) modeling. Efficacy data of anti-glypican 3 (GPC3) antibody drug conjugate (ADC) in a hepatocellular carcinoma (HCC) patient derived xenograft (PDX) model was used for evaluation of this proposed model. Our model was able to describe the kinetics of growth inhibition of HCC PDX models following treatment with anti-GPC3 ADC remarkably well. The estimated tumurostatic concentrations were used in tandem with human PKs translated from cynomolgus monkey for prediction of the efficacious dose. The projected efficacious human dose of anti-GPC3 ADC was in the range 0.20–0.63 mg/kg for the Q3W dosing regimen, with a median dose of 0.50 mg/kg. This publication is the first step in evaluating the applicability of GF in PK/PD modeling of ADCs. The authors are hopeful that incorporation of GF will result in an improved translation of the preclinical efficacy of ADCs to clinical settings and thereby better prediction of the efficacious human dose.  相似文献   
90.
Introduction: Nanomedicine has emerged as a major field of academic research with direct impact on human health. While a first generation of products has been successfully commercialized and has significantly contributed to enhance patient’s life, recent advances in material design and the emergence of new therapeutics are contributing to the development of more sophisticated systems. As the field matures, it is important to comprehend the challenges related to nanoparticle commercial development for a more efficient and predictable path to the clinic.

Areas covered: The review provides an overview of nanoparticle-based delivery systems currently on the market and in clinical trials, and discuss the principal challenges for their commercial development, both from a manufacturing and regulatory perspective, to help gain understanding of the translational path for these systems.

Expert opinion: Clinical translation of nanoparticle-based delivery systems remains challenging on account of their 3D nanostructure and requires robust nano-manufacturing process along with adequate analytical tools and methodologies. By identifying early enough in the development the product critical attributes and understanding their impact on the therapeutic performance, the developers of nanopharmaceuticals will be better equipped to develop efficient product pipelines. Second-generation products are expected to broaden nanopharmaceutical global market in the upcoming years.  相似文献   

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