知识三分法在儿童发展与教育中的意义

目的：根据儿童获取知识的方式对知识进行分类，探讨合适的认知教育方式。方法：从认知心理学角度，根据儿童获得和掌握知识的特点，对知识进行归纳和比较。结果：提出了记忆、理解和体验三类知识划分的概念、获取方式和特征。①记忆类知识的掌握主要依赖于单纯的识记，较少涉及理解和经验，具有很强的继承性和传播性。②理解类知识的掌握主要依赖于逻辑，记忆处于相对次要的地位，也具有可继承性和可传播性。③体验类知识的掌握在很大程度上依赖于经验或体验，以及在体验基础上的感悟。记忆和逻辑思维仅处于相对次要的位置，具有非继承性和非传播性：结论：记忆、理解和体验三类知识的增长均与儿童年龄的增长相关。其中体验类知识不能通过传统的课堂教学和教材来获得，对这类知识的特性与学习掌握方式的探讨于儿童的健康成长和知识扩展尤为重要。     

Hyperbaric Oxygen Treatment Produces an Antinociceptive Response Phase and Inhibits Astrocyte Activation and Inflammatory Response in a Rat Model of Neuropathic Pain

Hyperbaric oxygen (HBO) treatment has been proven to be a promising candidate for protection of the nervous system after acute injury in animal models of neuropathic pain. The purposes of this study were to examine the antinociceptive response phase induced by HBO treatment in a model of neuropathic pain and to determine the dependence of the treatment's mechanism of alleviating neuropathic pain on the inhibition of spinal astrocyte activation. Neuropathic pain was induced in rats by chronic constriction injury of the sciatic nerve. Mechanical threshold and thermal latency were tested preoperatively and for 1 week postoperatively, four times daily at fixed time points. Methane dicarboxylic aldehyde (MDA) and superoxide dismutase (SOD) parameters were used as indices of oxidative stress response and tested before and after the treatment. The inflammatory cytokines interleukin (IL)-1β and IL-10 were assayed in the sciatic nerve were with enzyme-linked immunoassay. Glial fibrillary acidic protein activation in the spinal cord was evaluated immunohistochemically. The rats exhibited temporary allodynia immediately after HBO treatment completion. This transient allodynia was closely associated with changes in MDA and SOD levels. A single HBO treatment caused a short-acting antinociceptive response phase. Repetitive HBO treatment led to a long-acting antinociceptive response phase and inhibited astrocyte activation. These results indicated that HBO treatment played a dual role in the aggravation and alleviation of neuropathic pain, though the aggravated pain effect (transient allodynia) was far less pronounced than the antinociceptive phase. Astrocyte inhibition and anti-inflammation may contribute to the antinociceptive effect of HBO treatment after nerve injury.     

mir-300 Promotes Self-Renewal and Inhibits the Differentiation of Glioma Stem-Like Cells

MicroRNAs (miRNAs) are small noncoding RNAs that have been critically implicated in several human cancers. miRNAs are thought to participate in various biological processes, including proliferation, cell cycle, apoptosis, and even the regulation of the stemness properties of cancer stem cells. In this study, we explore the potential role of miR-300 in glioma stem-like cells (GSLCs). We isolated GSLCs from glioma biopsy specimens and identified the stemness properties of the cells through neurosphere formation assays, multilineage differentiation ability analysis, and immunofluorescence analysis of glioma stem cell markers. We found that miR-300 is commonly upregulated in glioma tissues, and the expression of miR-300 was higher in GSLCs. The results of functional experiments demonstrated that miR-300 can enhance the self-renewal of GSLCs and reduce differentiation toward both astrocyte and neural fates. In addition, LZTS2 is a direct target of miR-300. In conclusion, our results demonstrate the critical role of miR-300 in GSLCs and its functions in LZTS2 inhibition and describe a new approach for the molecular regulation of tumor stem cells.     

微波透热治疗恶性肿瘤210例观察

应用微波透热治疗恶性肿瘤２１０例，近期疗效：原发癌９５例，临控１０例，显效３０例，临控显效率４２％；转移癌１１５例，临控１５例，显效３９例，临控显效率４７％。微波透热综合治疗可提高对放、化疗不敏感，常规治疗无效的难治愈恶性肿瘤的治疗效果。     

Role of IL‐17 and TGF‐β in peritoneal adhesion formation after surgical trauma

Peritoneal adhesions are fibrous tissues formed after surgery. Both cytokines and transforming growth factors (TGFs) are involved in this process. The objective of this study was to investigate the cross talk between these entities. Peritoneal drainage fluid after surgery from patients and rodent models was examined by enzyme‐linked immunosorbent assay and fluorescence‐activated cell sorter. Data showed that the concentrations of interferon (IFN)‐γ and interleukin (IL)‐17 reached their peaks 6–12 hours after surgery, whereas TGF‐β1 concentrations showed two postoperative peak time points at 2 and 72–96 hours. By neutralizing IFN‐γ, IL‐17 6–12 hours, and TGF‐β1 72–96 hours after surgery, the degree of adhesion reduced significantly. However, neutralizing TGF‐β1 2 hours after surgery did not affect adhesion formation. Furthermore, in vitro studies showed that compared with the fibroblasts that were directly stimulated with TGF‐β1, the prestimulation of IL‐17 promoted plasminogen activator inhibitor‐1 production while inhibiting tissue‐type plasminogen activator production. Moreover, additional stimulation with IFN‐γ enhanced this effect. Together, these data indicate that IL‐17 may promote adhesion formation by increasing the reaction of fibroblasts against TGF‐β1. Blocking IL‐17 might have a therapeutic potential in preventing adhesion formation after surgery.     

Prognostic Factors of Patients with Spinal Chondrosarcoma: A Retrospective Analysis of 98 Consecutive Patients in a Single Center

Purpose

Chondrosarcoma (CHS) in the spine is relatively rare and minimal information has been published in the literature regarding this subject. The objective of our study was to discuss the factors that may affect outcomes of patients with spinal CHS.

Methods

Univariate and multivariate analyses were performed to identify prognostic factors for recurrence, distant metastasis, and survival of spinal CHS. T test, χ ² test and rank sum test were used to analyze a single factor for recurrence and metastasis, while survival rate was estimated using the Kaplan–Meier method. Factors with p values of ≤0.1 were subjected to multivariate analyses by binary logistic regression analyses or Cox regression analyses. p Values of ≤0.05 were considered statistically significant.

Results

A total of 98 patients with spinal CHS were included in the study. The mean follow-up period was 49.7 months (range 6–178). Recurrence was detected in 42 patients after initial surgery in our center, while distant metastasis and death occurred in 24 and 32 cases, respectively. The statistical analyses suggested that pathology grade III was closely related with distant metastasis which was an independent prognostic factor for overall survival. Total en bloc spondylectomy could significantly decrease the risk of recurrence, distant metastasis, and death of patients with spinal CHS.

Conclusions

Total en bloc spondylectomy could significantly decrease the risk of recurrence and distant metastasis, and meanwhile improve overall survival of spinal CHS. Distant metastasis which was closely associated with pathology grade III was an adverse prognostic factor for overall survival of spinal CHS.     

Safe Zone for Superolateral Entry Pin Into the Distal Humerus in Children: An MRI Analysis

Background

The radial nerve is at risk for iatrogenic injury during placement of pins, screws, or wires around the distal humerus. Unlike adults, detailed anatomic information about the relationship of the nerve to the distal humerus is lacking in children.

Question/purposes

This study evaluates the relationship of the radial nerve to the distal humerus in a pediatric population on conventional MRI and proposes an anatomic safe zone using easily identifiable bony landmarks on an AP elbow radiograph.

Methods

To determine the course of the radial nerve at the lateral distal humerus, we reviewed 23 elbow radiographs and MRIs of 22 children (mean age, 9 ± 4 years; range, 3–12 years) obtained as part of their workup for various elbow conditions. We described a technique using distance ratios calculated as a percentage of the patient’s own transepicondylar distance, defined as the distance measured between the apices of the medial and lateral epicondyles, on the AP elbow radiograph and the midcoronal MR image. The cross-reference tool on a Picture Archiving and Communication System was then used to identify axial MR image at the level where the transepicondylar distance was measured. On this axial image, a line was drawn connecting the medial and lateral epicondyles (the transepicondylar axis) and its midpoint was determined. The radial nerve angle was measured by a line from the radial nerve to the midpoint of the transepicondylar axis and a line along the lateral half of the transepicondylar axis. On this axial slice, the closest distance from the nerve to the underlying cortex of the distal humerus was measured. To further localize the nerve along the distal humerus, predetermined percentages of the transepicondylar distance were projected proximally from the level of the transepicondylar axis along the longitudinal axis of the humerus on the midcoronal MR image. At these designated heights, the corresponding axial MR image was identified using the cross-reference tool and the nerve was mapped in a similar fashion. We then proposed a simpler method using a best-fit line drawn along the lateral supracondylar ridge on the AP radiograph to define the safe zone for lateral pin entry.

Results

On axial MR images, the radial nerve was located in the anterolateral quadrant with a mean radial nerve angle of 54° (range, 35°–87) at 0% transepicondylar distance (23 MRIs), 41° (range, 24°–63°) at 50% transepicondylar distance (23 MRIs), and ≥ 10° at 75% transepicondylar distance (on the 13 MRIs that extended this far cephalad). The mean closest distance between the radial nerve and the underlying humeral cortex was 10 mm (range, 3–26 mm) at 0% transepicondylar distance and 7 mm (3–16 mm) at 50% transepicondylar distance. On the AP elbow radiograph, the height of the lateral supracondylar ridge, determined by a best-fit line drawn along the lateral cortex of the ridge, diverged from the most proximal extent of the ridge at a point located at 60% transepicondylar distance (range, 51%–76%). At the corresponding location on the axial MR image, the nerve was located anterolaterally with a mean radial nerve angle of 39° (range, 15°–61°) and a mean distance of 6 mm (range, 2–10 mm) from the underlying humerus.

Conclusions

Our data suggest that percutaneous direct lateral entry Kirschner wires and half-pins can be safely inserted in the distal humerus in children along the transepicondylar axis, either at or slightly posterior to the lateral supracondylar ridge, when placed caudal to the point located where the lateral supracondylar ridge line diverges from the proximal extent of the supracondylar ridge on AP elbow radiograph.