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51.
《Chronobiology international》2013,30(10):1358-1365
In adolescence, the circadian preference shifts toward eveningness orientation. Eveningness seems to be negatively correlated with quality of life. The present study investigates influencing factors of this association and proposes a model for the mediating effects of sleep, sleep-related cognitions, and self-efficacy according to chronotype. The sample comprised N?=?280 adolescents (172 girls) aged 14–16 yrs (mean?=?15.19, SD?=?.76). Circadian preference, health-related quality of life (HRQoL), sleep disturbances, sleep-related dysfunctional cognitions, and general perceived self-efficacy were assessed online. Morning-orientated adolescents reported significantly higher HRQoL and less insomnia symptoms compared with evening-oriented chronotypes. In the total sample, insomnia symptoms mediated the relationship of chronotype and HRQoL. The strongest predictor of HRQoL in evening types was the degree of sleep-related dysfunctional cognitions. HRQoL in morning types was most strongly predicted by general self-efficacy, i.e., the global confidence in coping abilities. The findings support a negative relationship of eveningness and HRQoL in adolescents. Insomnia symptoms were identified to be mediating factors in this relationship. The influence of the mediating factors on HRQoL differed between morning and evening types. The model provides implications of how to enhance HRQoL in adolescents according to their circadian preference. (Author correspondence: )  相似文献   
52.
In the endoplasmic reticulum (ER), misfolded or improperly assembled proteins are exported to the cytoplasm and degraded by the ubiquitin-proteasome pathway through a process called ER-associated degradation (ERAD). ER-associated E3 ligases, which coordinate substrate recognition, export, and proteasome targeting, are key components of ERAD. Cystic fibrosis transmembrane conductance regulator (CFTR) is one ERAD substrate targeted to co-translational degradation by the E3 ligase RNF5/RMA1. RNF185 is a RING domain-containing polypeptide homologous to RNF5. We show that RNF185 controls the stability of CFTR and of the CFTRΔF508 mutant in a RING- and proteasome-dependent manner but does not control that of other classical ERAD model substrates. Reciprocally, its silencing stabilizes CFTR proteins. Turnover analyses indicate that, as RNF5, RNF185 targets CFTR to co-translational degradation. Importantly, however, simultaneous depletion of RNF5 and RNF185 profoundly blocks CFTRΔF508 degradation not only during translation but also after synthesis is complete. Our data thus identify RNF185 and RNF5 as a novel E3 ligase module that is central to the control of CFTR degradation.  相似文献   
53.
The Hazard analysis and critical control points (HACCP) is a preventive system which seeks to ensure food safety and security. It allows product protection and correction of errors, improves the costs derived from quality defects and reduces the final overcontrol. In this paper, the system is applied to the line of cultivation of mushrooms and other edible cultivated fungi. From all stages of the process, only the reception of covering materials (stage 1) and compost (stage 3), the pre-fruiting and induction (step 6) and the harvest (stage 7) have been considered as critical control point (CCP). The main hazards found were the presence of unauthorized phytosanitary products or above the permitted dose (stages 6 and 7), and the presence of pathogenic bacteria (stages 1 and 3) and/or heavy metals (stage 3). The implementation of this knowledge will allow the self-control of their productions based on the system HACCP to any plant dedicated to mushroom or other edible fungi cultivation.  相似文献   
54.
三角鲂和长春鳊肌肉营养成分分析与品质评价   总被引:1,自引:0,他引:1  
用常规方法测定、分析了三角鲂(Megalobrama tarminalis)和长春鳊(Parabramis pekinensis肌肉中营养成分组成与含量.结果显示,三角鲂肌肉蛋白质、脂肪含量分别为18.19%和3.06%,长春鳊肌肉蛋白质、脂肪含量分别为19.38%和2.89%.三角鲂和长春鳊肌肉中均检测出18种氨基酸,其中包括了8种人体必需氨基酸.三角鲂肌肉中氨基酸总量为76.27%,其中,8种人体必需氨基酸含量为32.17%,占氨基酸总量的42.18%;长春鳊肌肉中氨基酸总量为77.60%,其中,8种人体必需氨基酸含量为31.70%,占氨基酸总量的40.85%.必需氨基酸的构成比例基本符合FAO/WHO的标准.三角鲂肌肉中限制性氨基酸主要为甲硫氨酸加胱氨酸,必需氨基酸指数为63.55,4种呈味氨基酸为氨基酸总量的32.81%;长春鳊肌肉中限制性氨基酸主要为色氨酸,必需氨基酸指数为66.81,4种呈味氨基酸为氨基酸总量的33.80%.脂肪酸中二十碳五烯酸(EPA)与二十二碳六烯酸(DHA)含量均较高,三角鲂为7.96%,长春鳊为3.11%.矿物元素比值合理.以上分析表明,三角鲂和长春鳊均为营养价值、经济价值都较高的优质鱼类,相比而言,三角鲂肌肉脂肪、脂肪酸含量和质量更优,而长春鳊肌肉在蛋白质、氨基酸组成与含量方面更优.  相似文献   
55.
Esophageal cancer is common in China. There is a lack of treatment strategies for metastatic esophageal cancer (MEC) after radical surgery on the primary tumor. Cryoablation is an attractive option because tumor necrosis can be safely induced in a minimally invasive manner. This study assessed its therapeutic effect in MEC after failure of radical surgery. One hundred and forty patients met the inclusion criteria from May, 2003 to March, 2011. Comprehensive cryotherapy of multiple metastases was performed on 105 patients; 35 received chemotherapy. No severe complications occurred during or after cryoablation. Overall survival (OS) was assessed according to therapeutic protocol, pathologic type, treatment timing and number of procedures. The OS of patients who received comprehensive cryoablation (44 ± 20 months) was significantly longer than that of those who underwent chemotherapy (23 ± 24 months; P = 0.0006). In the cryotherapy group, the OS for squamous cell carcinoma (45 ± 19 months) was longer than that for adenocarcinoma (33 ± 18 months; P = 0.0435); the OS for timely cryoablation (46 ± 19 months) was longer than that for delayed cryoablation (33 ± 20 months; P = 0.0193); the OS for multiple cryoablation (50 ± 17 months) was longer than that for single cryoablation (37 ± 20 months; P = 0.0172); and the OS for cryo-immunotherapy (56 ± 17 months) was longer than that for cryoablation alone (39 ± 19 months; P = 0.0011). Thus, comprehensive cryotherapy may have advantages over chemotherapy in the treatment of MEC and, in patients with squamous cell carcinoma, supplementary immunotherapy and timely and multiple cryoablation may be associated with a better prognosis.  相似文献   
56.
系统分析食品、药品微生物检测实验室的质量控制方法,从总体环境条件控制、微生物室管理、样品管理、仪器设备管理、人员管理、培养基质量控制、标准菌(毒)种管理、操作过程控制、记录管理等9个方面进行系统分析,对微生物实验室的质量控制工作提供系统指导,提高微生物检测结果的准确性.  相似文献   
57.
生命科学发展迅速,实验动物级别逐渐提高,在保证生物制品实验结果可靠性前提下,完善动物由低级别向高级别过渡显得十分必要,最终目的达到实验动物标准化和动物实验规范化。对实验动物质量控制中的遗传标记和免疫学方法进行了综述。  相似文献   
58.
目的:对比管状胃代食管术与全胃代食管术治疗食管癌的安全性与有效性。方法:2005年1月到2015年2月选择我院收治的100例食管癌患者,根据随机数字表法分为治疗组与对照组各50例,所有患者都行食管癌切除术,同时对照组给予全胃代食管手术,治疗组给予管状胃代食管术,对两组患者围手术指标、并发症及生活质量状况进行观察比较。结果:所有患者完成手术,治疗组的手术时间、术中出血量、术后住院时间、术后胃肠减压时间及术后闭式引流时间都明显少于对照组(P0.05)。治疗组术后3个月反流性食管炎、胃排空障碍、胸胃综合征、吻合口狭窄、吻合口瘘等并发症发生情况明显少于对照组(P0.05),日常生活、一般状况、治疗相关症状、社会影响、情感活动评分都明显高于对照组(P0.05)。结论:相对于全胃代食管术,管状胃代食管术在治疗食管癌患者中的应用具有更好的安全性与有效性,值得进一步临床研究与推广。  相似文献   
59.
目的:探讨初治、年轻、中高/高危弥漫大B细胞淋巴瘤(diffuse large B cell lymphoma,DLBCL)的临床特征、治疗措施及预后影响因素。方法:回顾性分析2006年1月至2014年5月军事医学科学院附属医院淋巴瘤科收治的年龄≤60岁、年龄调整的国际预后指数(aa IPI)评分≥2分的初治DLBCL病例,进行疗效及预后相关因素的分析。结果:共收集到资料完整的DLBCL病例120例,中位随访28(4-106)个月,3年PFS率53.25%,OS率61.52%。单因素分析结果显示B症状、治疗方案及近期疗效、自体移植对无进展生存(PFS)及总体生存(OS)率的影响有统计学意义。多因素分析结果显示治疗方案、自体造血干细胞移植是影响PFS、OS率的独立影响因素。结论:年轻、中高/高危DLBCL具有高度异质性,病理细胞来源、Ki-67等在本组病例中未见显著预后意义,有待临床进一步探索。  相似文献   
60.
The global market for herbal medicine is growing steadily. The usage of herbal medicine is particularly common in many parts of Africa; the World Health Organization estimates that approximately 80% of Africans rely on traditional African medicines (TAMs) for treating various diseases. TAMs hold promise in preventive treatment, early disease intervention and personalized medicine. However, clinical integration of TAMs is restricted due to limited information concerning their characterization. Presently, many studies on TAMs utilize a reductionist approach, making it extremely difficult to understand the holistic modifying effects that these therapeutic agents may have on biological systems. Fortunately, emerging technologies such as metabolomics platforms adopt a ⿿top-down⿿ strategy that permits a holistic evaluation of the components, metabolic pathways and biomarkers modified by TAMs, which can aid in addressing common concerns over safety and toxicity, while also ensuring that quality control standards are met. Metabolomics approaches may also be beneficial for advancing our understanding of the efficacy and mechanism of action of TAMs, and may contribute to the advancement of research and drug discovery, early diagnosis, preventive treatment and TAMs-driven personalized medicine in Africa. This review also considers the main challenges that may hinder the adoption and integration of metabolomics approaches in research on TAMs in Africa and suggests possible solutions.  相似文献   
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