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101.
孤独症是一种病因不明的广泛性发育障碍疾病,它是孤独症谱系障碍的代表疾病,发病年龄早,大多在3岁以内起病,以社会交往障碍,言语交流障碍,动作行为的重复刻板和兴趣范围狭窄为三大临床核心症状。孤独症发病率呈逐年增高趋势,我国患者量已超过一百万。但是迄今为止仍没有特异的方法与手段对孤独症进行彻底有效地诊治,为社会和家庭带来了沉重的负担,因此,其发病机制是迫切需要研究的难题。目前国际上公认为遗传因素在孤独症的发病中起着重要作用,但对于致病基因的确定仍不明确。突触后致密物(PSD)在中枢神经系统神经递质和信息的传递过程中起重要作用,影响学习记忆及认知相关功能,而孤独症患者存在认知相关功能损伤的表现,二者可能存在一定的联系。本文对PSD基因功能以及与孤独症关系的研究加以综述,希望有助于孤独症的病因学研究,以期早日改善该病的诊疗及预防。 相似文献
102.
为明确不同寄主和不同信息化合物对豆大蓟马的行为影响,本文应用"Y"型嗅觉仪测定了豆大蓟马雌成虫对两种寄主植物花和不同浓度(v/v)下11种化合物的趋向性反应,结果表明:豆大蓟马对豇豆花、10-4烟酸乙酯、10-6烟酸乙酯、10-2橙花醇、10-2芳樟醇、10-6邻茴香醛和10-23-苯丙醛、10-43-苯丙醛具有极显著的趋向反应;对四季豆花和10-4橙花醇具有显著的趋向反应;10-4β-香茅醇、10-6β-香茅醇和10-6苯甲醛对豆大蓟马具有显著的驱避反应。不同浓度同一化合物对豆大蓟马的吸引作用也存在显著差异。实验结果可为进一步开发利用信息化合物田间防治豆大蓟马提供参考。 相似文献
103.
我们在对染色质修饰作用进行研究的过程中,发现以往的研究只关注化学修饰间的线性关系,而对于非线性关系未充分重视。为此,我们对Pokholok等(2005)人测出的酵母组蛋白甲基化修饰与乙酰化修饰数据进行了插值处理,得到了16种全基因组组蛋白修饰数据。然后对每组修饰数据在TSS位点上、下游各取1 000 bp进行对齐、平均、平滑和归一化处理。我们发现,根据酵母基因转录水平数据,可将组蛋白修饰数据分为两大类:一类是转录增强修饰群体,一类是转录抑制或转录无关修饰群体。为了揭示不同转录活性基因上修饰间的复杂关系,我们分别利用Pearson相关分析法和Reshef等(2011)人提出的MINE算法得到了以上修饰之间的相关性。最后对该结果进行分析,得到了修饰之间的一些非线性关系,同时发现同群体间修饰的关联性更强。 相似文献
104.
Leilei Xia Xianjin Wang Tianyuan Xu Xiaohua Zhang Zhaowei Zhu Liang Qin Xiang Zhang Chen Fang Minguang Zhang Shan Zhong Zhoujun Shen 《PloS one》2015,10(3)
Objective
To critically review the currently available evidence of studies comparing robot-assisted radical cystectomy (RARC) with open radical cystectomy (ORC).Methods
A comprehensive review of the literature from Pubmed, Web of Science and Scopus was performed in April 2014. All relevant studies comparing RARC with ORC were included for further screening. A pooled meta-analysis of all comparative studies was performed and publication bias was assessed by a funnel plot.Results
Nineteen studies were included for the analysis, including a total of 1779 patients (787 patients in the RARC group and 992 patients in the ORC group). Although RARC was associated with longer operative time (p <0.0001), patients in this group might benefit from significantly lower overall perioperative complication rates within 30 days and 90 days (p = 0.005 and 0.0002, respectively), more lymph node yields (p = 0.009), less estimated blood loss (p <0.00001), lower need for perioperative and intraoperative transfusions (p <0.0001 and <0.0001, respectively), and shorter postoperative length of stay (p = 0.0002). There was no difference between two groups regarding positive surgical margin rates (p = 0.19).Conclusions
RARC appears to be an efficient alternative to ORC with advantages of less perioperative complications, more lymph node yields, less estimated blood loss, lower need for transfusions, and shorter postoperative length of stay. Further studies should be performed to compare the long-term oncologic outcomes between RARC and ORC. 相似文献105.
106.
107.
Jian Yang Robert A. Spicer Teresa E. V. Spicer Nan Crystal Arens Frédéric M. B. Jacques Tao Su Elizabeth M. Kennedy Alexei B. Herman David C. Steart Gaurav Srivastava Rakesh C. Mehrotra Paul J. Valdes Naresh C. Mehrotra Zhe‐Kun Zhou Jiang‐Shan Lai 《Global Ecology and Biogeography》2015,24(10):1113-1125
108.
109.
Fen Liu Yi-Ning Yang Xiang Xie Xiao-Mei Li Xiang Ma Zhen-Yan Fu Bang-Dang Chen Ying Huang Chun-Fang Shan Yi-Tong Ma Xiao-Ming Gao 《PloS one》2015,10(8)
Background
The prevalence and risk factors of congenital heart disease among Xinjiang, northwestern part of China is currently unknown.Methods
This multiple-ethnic, community-based, cross-sectional study was conducted to estimate the prevalence and distribution of congenital heart disease (CHD) in Xinjiang, northwestern part of China. Four major ethnics, Uygur, Han, Kazak, and Hui children in this region were investigated during February 2010 and May 2012.Results
A total of 14,530 children (0–18 yr) were examined. Of these children, 240 (boys, 43.8%, and girls, 56.3%) were identified with CHD, giving an overall prevalence of 16.5‰ (17.7‰ in Uygur, 6.9‰ in Han, 11.4‰ in Kazak, and 38.1‰ in Hui Chinese, respectively). Ventricular septal defect (VSD, 29.2%), atrial septal defect (ASD, 20.8%), patent ductus arteriosus (PDA, 13.7%), acleistocardia (13.7%), Bicuspid aortic valve (7.9%), pulmonary valve stenosis (5.4%), and tetralogy of fallot (TOF, 4.2%) were common cyanotic and cyanotic defects observed. Compared to non-CHD children, children with CHD had a higher percentage of history of abortion, CHD history of family, consanguinity and premature birth (all P<0.05). In CHD children, 24% of mothers caught a cold, 10% had a febrile illness and 6.7% received antibiotic treatment during the first trimester of pregnancy, that were higher than non-CHD group (all P<0.05).Conclusion
The overall prevalence of CHD in four ethnic children at ages 0–18 yr in Xinjiang was 16.5‰. VSD, ASD and TOF were the most common acyanotic and cyanotic congenital heart defects, respectively. This study also identified some modifiable risk factors that may contribute to the incidence of CHD among the 4 ethnic groups. 相似文献110.