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41.
目的 从问卷调查技术认知、实践的角度,探讨预防医学专业学生调查问卷技术相关态度的影响因素,从而为有针对性地进行预防医学专业有关问卷调查技术教学改革提供参考.方法 对河北省2所高校公共卫生学院的预防医学专业五年级全体本科生进行调查,共计141人.自行设计调查问卷.影响因素分析采用Logistic多元回归模型.结果 调查对象认为问卷调查技术在获取人群疾病和健康信息方面的作用“很大”或“较大”者占75.17%,认为问卷调查研究结果“真实”或“较真实”者占65.25%,有58.87%认为调查问卷的科学性“很高”或“较高”,有62.41%认为开展问卷调查“很难”或“较难”.预防医学专业学生对问卷调查技术作用的态度与其调查问卷测量属性知晓情况、问卷调查基本原则的知晓情况有关,对问卷调查研究结果真实性的态度与问卷调查基本原则的知晓情况、参加问卷调查设计次数有关,参加问卷调查设计次数与学生对调查问卷工具科学性态度有关,学校、性别、调查问卷测量属性知晓情况与问卷调查研究难度态度有关.结论 预防医学医学生对问卷调查技术的认知、实践水平对其问卷调查技术相关态度有影响.建议高校加强问卷调查技术跨学科综合理论与实践教学,提升学生对问卷调查技术的正向态度.  相似文献   
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Metallothioneins (MTs) are a group of metal binding proteins thought to play a role in the detoxification of heavy metals. Here we showed by microarray and validation analyses that MT1h, a member of MT, is down‐regulated in many human malignancies. Low expression of MT1h was associated with poor clinical outcomes in both prostate and liver cancer. We found that the promoter region of MT1h was hypermethylated in cancer and that demethylation of the MT1h promoter reversed the suppression of MT1h expression. Forced expression of MT1h induced cell growth arrest, suppressed colony formation, retarded migration, and reduced invasion. SCID mice with tumour xenografts with inducible MT1h expression had lower tumour volumes as well as fewer metastases and deaths than uninduced controls. MT1h was found to interact with euchromatin histone methyltransferase 1 (EHMT1) and enhanced its methyltransferase activity on histone 3. Knocking down of EHMT1 or a mutation in MT1h that abrogates its interaction with EHMT1 abrogated MT1h tumour suppressor activity. This demonstrates tumour suppressor activity in a heavy metal binding protein that is dependent on activation of histone methylation. Copyright © 2013 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.  相似文献   
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In clinical tumor therapy, traditional treatments such as surgery, radiotherapy and chemotherapy all have their own limitations. With the development of nanotechnology, new therapeutic methods based on nanomaterials such as photothermal therapy (PTT) have also emerged. PTT takes advantage of the poor thermal tolerance of tumor cells and uses the heat generated by photothermal reagents to kill tumor cells. A transition metal sulfide represented as Cu2S is an ideal photothermal reagent because of its easy preparation, high extinction coefficient and photothermal conversion efficiency. Surface modification of nanoparticles (NPs) is also necessary, which not only can reduce toxicity and improve colloidal stability, but also can provide the possibility of further chemotherapeutic drug loading. In this work, we report the fabrication of Tween-20 (Tw20)-modified and doxorubicin (Dox)-loaded Cu2S NPs (Cu2S/Dox@Tw20 NPs), which significantly improves the performance in tumor therapy. Apart from the enhancement of colloidal stability and biocompatibility, the drug loading rate of Dox in Tw20 reaches 11.3%. Because of the loading of Dox, Cu2S/Dox@Tw20 NPs exhibit chemotherapeutic behaviors and the tumor inhibition rate is 76.2%. Further combined with a near-infrared laser, the high temperature directly leads to the apoptosis of a large number of tumor cells, while the release of chemotherapeutic drugs under heat can not only continue to kill residual tumor cells, but also inhibit tumor recurrence. Therefore, with the combination of PTT and chemotherapy, the tumor was completely eliminated. Both hematological analysis and histopathological analysis proved that our experiments are safe.

In clinical tumor therapy, traditional treatments such as surgery, radiotherapy and chemotherapy all have their own limitations.  相似文献   
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目的:通过采用无托槽隐形矫治器与固定矫治器拔除4颗第一前磨牙的临床分析,探讨无托槽隐形矫治技术的具体优势。方法:选取2010年6月-2014年6月在我院拔除4颗第一前磨牙矫治拥挤的患者90例,随机均分为对照组和观察组,其中对照组采用固定矫治器进行治疗,观察组采用无托槽隐形矫治器进行治疗,对比两组患者的治疗效果。结果:90例患者均实现了牙齿排列的整齐并有效关闭了拔牙的间隙。观察组在疗程评估的有效率方面略高于参照组,但是两组并没有显著的差异。而在美观满意度、舒适满意度和便捷满意度3个指标上,观察组的满意度明显高于参照组,存在着显著的差别。结论:固定矫治器和无托槽隐形矫治器对于拔除4颗第一前磨牙矫治拥挤均能形成显著的疗效,但是无托槽隐形矫治器不但美观大方,还能够大大降低医生的劳动强度,所以在拔除4颗第一前磨牙矫治拥挤方面,无托槽隐形矫治器相对于固定矫治器具有较大的优势。  相似文献   
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Objective

To investigate genetic subtypes of inherited bone marrow failure syndrome Fanconi anemia (FA) in Sebia. FA-D2 subtype was found to be the most frequent genetic subtype among investigated FA patients; specific observations of FA-D2 phenotype are pointed out.

Methods

Several biological endpoints of FA cells in vitro such as radiation-induced level of lymphocyte micronuclei (radiosensitivity), base line and radiation induced level of the DNA double strand breaks (DSBs), leukocyte apoptosis, and telomere capping function were assessed.

Results

The results indicate that all FA-D2 patients display radioresistant in vitro response, which is seen as significantly reduced yield of radiation-induced micronuclei. On the contrary, FA-A patients display radiosensitive in vitro response seen as increased number of radiation-induced micronuclei (MN). A massive elimination of irradiated cells via apoptosis is found in both FA-A and FA-D2 subtypes. In FA-A subtype apoptosis positively relates with the yield of radiation-induced MN, whereas in FA-D2 subtype apoptosis relates with a high percentage of cells carrying dysfunctional telomeres. The present results unequivocally demonstrate that cytokinesis-block micronucleus (CBMN) assay and analyses of telomere capping function can be used to distinguish FA-D2 and FA-A complementation groups.

Conclusions

Considering all biological endpoints were analyzed, it can be concluded that all FA patients are radiosensitive, regardless of their complementation group. Thus, using CBMN test and telomere capping function analysis can discriminate FA-A from FA-D2 complementation groups, which could be important for assessment the conditioning regimens prior to bone marrow transplantation.  相似文献   
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