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Glioblastoma muhiforme (GBM) is a highly invasive brain tumour that is unvaryingly fatal in humans clesplte even aggres- sive therapeutic approaches such as surgical resection followed by chemotherapy and radiotherapy. Unconventional treatment options such as gene therapy provide an intriguing option for curbing glioma related deaths. To date, gene therapy has yielded encouraging results in preclinical animal models as well as promising safety profiles in phase I clinical trials, but has failed to demonstrate significant therapeutic efficacy in phase III clinical trials. The most widely studied antiglioma gene therapy strategies are suicide gene therapy, genetic immuno- therapy and oncolytic virotherapy, and we have attributed the challenging transition of these modalities into the clinic to four major road- blocks : ( 1 ) anatomical features of the central nervous system, (2) the host immune system, (3) heterogeneity and invasiveness of GBM and (4) limitations in current GBM animal models. In this review, we discuss possible ways to jump these hurdles and develop new gene therapies that may be used alone or in synergy with other modalities to provide a powerful treatment option for patients with GBM.  相似文献   
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Mass lesions presenting at the craniocervical junction often present a unique challenge due to the complex anatomic arrangement limiting access for tissue diagnosis. The transoral approach has predominantly been used for percutaneous vertebroplasty of high cervical vertebrae with limited literature describing image guided biopsy for bony lesions in this region in the pediatric patient. We describe a technique of computed tomography guided transoral biopsy of a poorly differentiated chordoma located at the C1–C2 level in a 5-year-old child, and review this diagnosis.  相似文献   
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Abstract

We used consensual qualitative research to analyze interviews with 12 clients about their termination from psychotherapy. Those who had positive termination experiences reported a strong therapeutic relationship and positive outcomes of therapy. They terminated primarily for logistical or financial reasons; their termination, post-termination plans, and feelings about termination were discussed in advance with their therapist, as was their growth in therapy, leading to mostly positive effects of the termination. In contrast, those who had problematic terminations reported a mixed therapeutic relationship and mixed outcomes of therapy. They usually terminated abruptly because of a therapeutic rupture, and thus termination was rarely planned and discussed in advance, rendering it a negative experience. Implications of these findings are addressed.  相似文献   
55.
The primate visual cortex exhibits two anatomically distinct pathways (dorsal and ventral). According to the “two visual systems hypothesis” (TVSH) of Milner and Goodale (The visual brain in action. Oxford University Press, Oxford, 1995), this anatomical distinction corresponds to a functional division of labor between vision-for-action (dorsal) and vision-for-perception (ventral). This proposal is supported by evidence that, in healthy volunteers, perceptual responses are affected by visual illusions, whereas motor responses to the same illusion-inducing stimuli are not. However, previously we have shown that the amplitude of saccadic eye movements is modified by the Müller–Lyer illusion in a similar manner as perceptual responses. Here we extend this finding to reflexive and voluntary (memory-guided) saccades. We show that both types of saccade can be strongly affected by the illusion. In our studies, the effect on reflexive saccades was comparable to that usually observed with verbal reports (an effect size of 22 ± 8%), whereas the effect on voluntary saccades was smaller (11 ± 11%). In addition, both types of saccade provide evidence for the scaling bias usually observed in perceptual responses. We suggest that previous studies may have employed methods that generally reduced the effect of the illusion. Interpretations of dissociations between reflexive and voluntary saccades in terms of the TVSH appear to be premature.  相似文献   
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Bishop K  Addy L  Knox J 《Dental update》2007,34(1):30-2, 34, 37-8
Restoration of spaces in hypodontia patients needs to take into account many factors including, the number of missing teeth, the distribution of space, the size of the teeth, and the age of the patient. This paper considers adhesive and conventional bridgework, as well as removal alternatives for the restoration of spaces. The various merits of each are discussed, together with treatment planning considerations for such cases.  相似文献   
58.
This study identified and compared characteristics of 'best' and 'worst' clinical teachers as perceived by university nursing faculty and students. The Nursing Clinical Teacher Effectiveness Inventory (NCTEI) was distributed to 201 volunteer subjects. This survey instrument, developed by the authors, contains 48 clinical teacher characteristics grouped into five categories. Each participant was asked to rate, using the NCTEI, the 'best' and them the 'worst' clinical teacher from past observations. Results showed both groups perceived that being a good role model was the highest rated characteristic for 'best' teachers and the 'lowest' rated characteristic for 'worst' teachers. Faculty and students' perceptions were fairly similar as to highest rated characteristics of 'best' clinical teachers. Less agreement was noted about the characteristics of 'worst' clinical teachers. When categories of clinical teacher characteristics were compared, there were significant differences between the ratings of faculty and students for 'best' clinical teachers, but none for 'worst' clinical teachers.  相似文献   
59.
Background: The aim of this study was to quantify the stabilizing properties of a 3-dimensional (3D)-printed short-arm cast and compare those properties with traditional fiberglass casts in a cadaveric subacute distal radius fracture model. Methods: A cadaveric subacute fracture model was created in 8 pairs of forearms. The specimens were equally allocated to a fiberglass cast or 3D-printed cast group. All specimens were subjected to 3 biomechanical testing modalities simulating daily life use: flexion and extension of digits, pronation and supination of the hand, and 3-point bending. Between each loading modality, radiological evaluation of the specimens was performed to evaluate possible interval displacement. Interfragmentary motion was quantified using a 3D motion-tracking system. Results: Radiographic assessment did not reveal statistically significant differences in radiographic parameters between the 2 groups before and after biomechanical testing. A statistically significant difference in interfragmentary motion was calculated with the 3-point bending test, with a mean difference of 0.44 (±0.48) mm of motion. Conclusions: A statistically significant difference in interfragmentary motion between the 2 casting groups was only identified in 3-point bending. However, the clinical relevance of this motion remains unclear as the absolute motion is less than 1 mm. The results of this study show noninferiority of the 3D-printed casts compared with the traditional fiberglass casts in immobilizing a subacute distal radius fracture model. These results support the execution of a prospective randomized clinical trial comparing both casting techniques.  相似文献   
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