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991.
目的 了解江门市高三学生近视流行情况及相关影响因素,为制定学生近视防控策略提供相关依据。方法 采用分层随机抽样的方法,从江门市随机抽取11所高中,最终共纳入1 075名学生,进行视力检测并开展问卷调查。结果 1 075名高三学生中,近视患病率为79.81%。城市与农村、父母文化程度不同的学生近视患病率存在差异(P均<0.05)。秩相关显示近视程度与每天看电视时长、每天课外做功课时长、每天玩电子游戏时长、每天上网时长、每周参加课外补习班时长呈正相关(r分别为0.025、0.20、0.27、0.21、0.18,P均<0.05);与不讨厌吃某类蔬菜、肉类、水果、7天内每天至少运动60 min为负相关(r分别为-0.06、-0.10,P均<0.05)。非条件logistic回归分析发现每天课外做功课时长≥4.1 h、每天玩电子游戏时长≥4.1 h、每天上网时长≥4.1 h、每周参加课外补习班时长≥8.1 h,是导致近视的危险因素(OR均>1,P值均<0.05)。结论 江门市高三学生近视现况不容乐观,影响因素多样,建议重视学生健康教育,加强学生、家庭、学校、社区、社会联动的防近视体系的建立。 相似文献
992.
Siu Hong Cheung Wai Yin Wilson Kwan Kwan Pok Tsui Tam Lin Chow 《American journal of otolaryngology》2018,39(3):286-289
Purpose
Benign parotid tumors are adequately treated with partial parotidectomy, which is often performed under general anesthesia (GA). We have reported our preliminary results on the feasibility to perform parotidectomy under local anesthesia (LA). We hereby present our accumulated experience of partial parotidectomy under LA to further consolidate its feasibility, efficacy and safety in a larger series.Materials and methods
Case series review was carried out using our own center patients' database. 50 patients with parotid tumors were treated with partial parotidectomy under LA, using a retrograde nerve dissection approach from January 2006 to October 2016. The inclusion criteria encompassed mobile parotid nodules primarily operated after non-suspicious fine-needle aspiration cytology. Their demographics, complications and outcomes were evaluated.Results
No procedure required conversion to GA. There were 48 benign tumors and 2 lymphomas based on the histopathologic examination. The commonest pathologies were pleomorphic adenoma (40%), Warthin's tumor (38%) and cyst (8%). The mean tumor size was 2.68?±?1.5?cm and the mean operative time was 91.5?±?34.7?min. Forty-two operations were done as day cases. Ten (20%) patients suffered from transient ear lobe numbness and two (4%) patients had sialocele. Transient facial palsy occurred in 2(4%) patients while another patient (2%) had persistent House-Brackmann grade II facial palsy. No tumor recurrence was noted during follow-up period.Conclusions
Partial parotidectomy adopting a retrograde nerve dissection under LA is feasible and minimally invasive in treating benign parotid tumors. It can avoid the adverse effects of general anesthesia and promote day surgery or minimize hospital stay. 相似文献993.
994.
Anne W. Lee Wai Tong Ng Jian Ji Pan Sharon S. Poh Yong Chan Ahn Hussain AlHussain June Corry Cai Grau Vincent Grégoire Kevin J. Harrington Chao Su Hu Dora L. Kwong Johannes A. Langendijk Quynh Thu Le Nancy Y. Lee Jin Ching Lin Tai Xiang Lu William M. Mendenhall Joseph T. Wee 《Radiotherapy and oncology》2018,126(1):25-36
Purpose
Target delineation in nasopharyngeal carcinoma (NPC) often proves challenging because of the notoriously narrow therapeutic margin. High doses are needed to achieve optimal levels of tumour control, and dosimetric inadequacy remains one of the most important independent factors affecting treatment outcome.Method
A review of the available literature addressing the natural behaviour of NPC and correlation between clinical and pathological aspects of the disease was conducted. Existing international guidelines as well as published protocols specified by clinical trials on contouring of clinical target volumes (CTV) were compared. This information was then summarized into a preliminary draft guideline which was then circulated to international experts in the field for exchange of opinions and subsequent voting on areas with the greatest controversies.Results
Common areas of uncertainty and variation in practices among experts experienced in radiation therapy for NPC were elucidated. Iterative revisions were made based on extensive discussion and final voting on controversial areas by the expert panel, to formulate the recommendations on contouring of CTV based on optimal geometric expansion and anatomical editing for those structures with substantial risk of microscopic infiltration.Conclusion
Through this comprehensive review of available evidence and best practices at major institutions, as well as interactive exchange of vast experience by international experts, this set of consensus guidelines has been developed to provide a practical reference for appropriate contouring to ensure optimal target coverage. However, the final decision on the treatment volumes should be based on full consideration of individual patients’ factors and facilities of an individual centre (including the quality of imaging methods and the precision of treatment delivery). 相似文献995.
996.
Erectile dysfunction is a common benign disorder with significant impact on the quality of life of patients. Ten percent of the male adult population is affected. Sildenafil has been proven to be an effective and safe oral medication for the treatment of erectile dysfunction with a response rate of 78%. The incidence of side effects is low (10%) and side effects are usually mild and transient. The drug should be prescribed only after proper history taking, physical examination and basic investigations. 相似文献
997.
998.
Telomerase as a prognostic marker in breast cancer: high-throughput tissue microarray analysis of hTERT and hTR 总被引:14,自引:0,他引:14
999.
Functional magnetic resonance imaging (fMRI) based on both perfusion and blood oxygenation level-dependent (BOLD) contrasts has been widely applied in spatiotemporal mapping of the human brain function. Temporal resolving power of fMRI is limited by the smoothed hemodynamic response function dispersed from the neuronal activity. In this study, temporal modulation transfer functions were utilized to quantify the resolving powers of perfusion and BOLD fMR signals in time domain. The impulse response function was determined using brief visual stimulations and event-related image acquisition schemes. An important feature of arterial spin labeling techniques is that quantitative perfusion and BOLD signals could be simultaneously acquired. This simultaneous BOLD response may arise from signals that are more proximal to capillary beds, and its temporal resolution may be different from that of the typical BOLD response. Therefore, we assessed and compared the temporal resolving capabilities of perfusion, simultaneous BOLD, and the typical BOLD response obtained from the gradient echo EPI pulse sequence. Full-width-at-half-maximums of perfusion and simultaneous BOLD measurements were significantly smaller than that of BOLD ones (4.3+/- 0.6 s vs 5.5 +/- 0.9 s, p<0.02 and 4.7 +/- 1.3 s vs 5.5 +/- 0.9 s, p<0.01, respectively). The corresponding temporal resolving powers of perfusion and simultaneous BOLD signals were statistically better than that of BOLD signals (0.23 +/- 0.03 Hz vs 0.17 +/- 0.02 Hz, p<0.01 and 0.21 +/- 0.04 Hz vs 0.17 +/- 0.02 Hz, p<0.01, respectively). Our results showed that the typical BOLD response was significantly smoothed from the perfusion response, thus resulting in a degraded temporal resolving power. However, results from the simultaneous BOLD and perfusion measurements were not significantly different. Biophysical implications of the experimental outcomes were further investigated using a computer simulation based on the Balloon model. By fitting the measured data into the model, an apparently longer transit time was obtained for the typical BOLD signal (1.7 s), comparing to that for the simultaneous BOLD one (1.2 s). Therefore, the simultaneous BOLD signal was regarded as less susceptible to the variations from local draining veins. Combining the simulation result with the significantly discrepant resolving powers between the two BOLD signals, we speculated that the blurred effects from large vessels played a predominant role that further reduced the temporal resolution of the BOLD-based fMRI from the perfusion response. 相似文献
1000.
中学生焦虑、抑郁与生活事件和应对方式研究 总被引:6,自引:3,他引:6
中学生处于心理发育的重要时期 ,也是各种心理问题的高发阶段[1- 2 ] 。初三毕业生面临升学的压力 ,这部分同学的心理状况更应引起关注。在各种心理问题中 ,焦虑、抑郁是常见的症状 ,本文拟调查初三毕业生的焦虑、抑郁状况 ,并通过生活事件和应对方式调查 ,以便发现焦虑、抑郁的影响因素 ,这对初三毕业生心理问题的预防和干预将有重要意义。1 对象和方法1.1 对象选取一所普通中学 ,以所有初三毕业生为调查对象 ,发放 35 2份调查表 ,共收集 331名资料完整者 ,资料回收率 94 .0 3%。 331名学生中 ,男生 171名 ,女生 16 0名 ,平均年龄 15 .4 … 相似文献