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111.
112.
The influence of advertising on social networks and its effect on young people’s self-image has been studied. This study first explored the frequency of published videos reposted on social networks using different Application Programming Interfaces as search engines. The study also implemented self-valuation surveys assessed by experts and distributed among mental health professionals who assessed the influence of these social networks. Finally, the survey was designed regarding social networks and body assessment and distributed among Córdoba university students (N = 328). The majority of health professionals concluded that there is an elevated influence of social networks on eating disorders, assessing advertising as a risk factor with a value of 4.60 out of 5. Young people’s perceptions of their body image indicate that women’s degree of satisfaction is highly correlated with the frequency of their connections to social networks, with the body image those women present and with the effect of advertising. Conversely, this high correlation and influence does not exist in men.  相似文献   
113.
Vitamin A deficiency (VAD) is a serious and widespread public health problem and the leading cause of preventable blindness in young children. It is also associated with increased rates of death from severe infections, especially in developing countries. Over the past 35 years, researchers have examined the numerous activities of vitamin A in different tissues of the human body. VAD can lead to a series of ocular symptoms, anemia, and weak resistance to infection, which can increase the severity of infectious diseases and the risk of death. Cell development, vision, growth, and normal metabolism are among the vital processes that are insufficiently supported in the presence of VAD. VAD leads to impaired tissue function especially during the developmental periods of infancy, childhood, pregnancy, and lactation. We describe a multidirectional model of VAD that demonstrates how VAD can have progressive, negative effects on vital processes of the human body throughout the life cycle. This model starts with impaired intake and its link to decreased absorption and digestion and includes outcomes such as malnutrition, inflammation, and improper growth processes, including possible mechanisms. Together, these clinical and biochemical manifestations contribute to the vicious cycle of VAD.  相似文献   
114.
细长柱的二阶效应在结构设计中容易被忽略。该文通过对“虚柱法”理论的阐述,总结出细长柱可根据“虚柱法”来计算二阶效应:由于细长柱的二阶效应与构件侧向荷载无关,故只需要输入构件轴向压力来得到二阶效应的刚度,并叠加单元力学属性的刚度。就可以得到考虑二阶效应的细长柱内力计算方法。最后通过sap2000算例得到验证。  相似文献   
115.
昼夜节律睡眠-觉醒障碍是指睡眠-觉醒周期与人体24 h生物节律失调所致的一类睡眠疾病,它可以影响人体的认知功能和代谢等过程,还能促进恶性肿瘤的发生发展——通过改变时钟基因表达直接促进肿瘤增殖,并通过抑制褪黑素的分泌等内分泌机制间接加速肿瘤发展。本文阐述了昼夜节律睡眠-觉醒障碍的定义、它导致的病理状态以及它对恶性肿瘤发生发展的影响,以期为昼夜节律性睡眠-觉醒障碍影响的肿瘤发生发展的防治提供可能的治疗措施。  相似文献   
116.
Starting from suvorexant (trade name Belsomra), we successfully identified interesting templates leading to potent dual orexin receptor antagonists (DORAs) via a scaffold‐hopping approach. Structure–activity relationship optimization allowed us not only to improve the antagonistic potency on both orexin 1 and orexin 2 receptors (Ox1 and Ox2, respectively), but also to increase metabolic stability in human liver microsomes (HLM), decrease time‐dependent inhibition of cytochrome P450 (CYP) 3A4, and decrease P‐glycoprotein (Pgp)‐mediated efflux. Compound 80 c [{(1S,6R)‐3‐(6,7‐difluoroquinoxalin‐2‐yl)‐3,8‐diazabicyclo[4.2.0]octan‐8‐yl}(4‐methyl‐[1,1′‐biphenyl]‐2‐yl)methanone] is a potent and selective DORA that inhibits the stimulating effects of orexin peptides OXA and OXB at both Ox1 and Ox2. In calcium‐release assays, 80 c was found to exhibit an insurmountable antagonistic profile at both Ox1 and Ox2, while displaying a sleep‐promoting effect in rat and dog models, similar to that of the benchmark compound suvorexant.  相似文献   
117.
High‐resolution imaging of middle‐ear geometry is necessary for finite‐element modeling. Although micro‐computed tomography (microCT) is widely used because of its ability to image bony structures of the middle ear, it is difficult to visualize soft tissues – including the tympanic membrane and the suspensory ligaments/tendons – because of lack of contrast. The objective of this research is to quantitatively evaluate the efficacy of iodine potassium iodide (IKI) solution as a contrast agent. Six human temporal bones were used in this experiment, which were obtained in right‐left pairs, from three cadaveric heads. All bones were fixed using formaldehyde. Three bones (one from each pair) were stained in IKI solution for 2 days, whereas the other three were not stained. Samples were scanned using a microCT system at a resolution of 20 μm. Eight soft tissues in the middle ear were segmented: anterior mallear ligament, incudomallear joint, lateral mallear ligament, posterior incudal ligament, stapedial annular ligament, stapedius muscle, tympanic membrane and tensor tympani muscle. Contrast‐to‐noise ratios (CNRs) of each soft tissue were calculated for each temporal bone. Combined CNRs of the soft tissues in unstained samples were 6.1 ± 3.0, whereas they were 8.1 ± 2.7 in stained samples. Results from Welch's t‐test indicate significant difference between the two groups at a 95% confidence interval. Results for paired t‐tests for each of the individual soft tissues also indicated significant improvement of contrast in all tissues after staining. Relatively large soft tissues in the middle ear such as the tympanic membrane and the tensor tympani muscle were impacted by staining more than smaller tissues such as the stapedial annular ligament. The increase in contrast with IKI solution confirms its potential application in automatic segmentation of the middle‐ear soft tissues.  相似文献   
118.
An efficient rhodium(III)‐catalyzed direct C7 alkynylation of indoline C H bonds with the alkynylated hypervalent iodine reagents has been developed. This reaction proceeds smoothly under mild conditions over a wide structural scope with high site‐selectivity and excellent functional‐group tolerance. N‐Acetyl as well as other N‐acyls served as effective directing groups (DG). This procedure allows for the synthesis of a variety of 7‐alkynyl‐substituted indolines in good to excellent yield. More significantly, C7‐alkynylated indoles through further transformations have been successfully accessed.

  相似文献   

119.
影响汽车车身磷化因素的探讨   总被引:1,自引:0,他引:1  
探讨了汽车车身磷化处理工艺在实际生产中的影响因素:主要有磷化液的酸度和温度、磷化促进剂、工件材质和表面状态、磷化前的表面处理、酸洗等。分析了汽车车身磷化的常见缺陷,并给出了防治措施。  相似文献   
120.
单元式生产方式分析及对策研究   总被引:3,自引:0,他引:3  
从兼顾批量生产的经济性和单件订货生产的柔性的角度,以某变频器厂的实际运作为例,论述了单元式生产方式(cell line)相对传统流水线具有柔性高、建立容易、生产效率高、节约空间、强调团队合作等优点.针对现存的设备需要量增加、作业员素质要求提高、工作地布置和物料供应复杂、容易缺少约束和激励等问题,提出了cell line建立的四个条件,并提出通过设备共用、完善新人培训机制、合理规划布局、配备"多能工"、进行良性竞争等措施,可以很好地解决上述问题,使cell line生产更具柔性和适应性.  相似文献   
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