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61.
Kate Fox Hamish Meffin Owen Burns Carla J. Abbott Penelope J. Allen Nicholas L. Opie Ceara McGowan Jonathan Yeoh Arman Ahnood Chi D. Luu Rosemary Cicione Alexia L. Saunders Michelle McPhedran Lisa Cardamone Joel Villalobos David J. Garrett David A. X. Nayagam Nicholas V. Apollo Kumaravelu Ganesan Mohit N. Shivdasani Alastair Stacey Mathilde Escudie Samantha Lichter Robert K. Shepherd Steven Prawer 《Artificial organs》2016,40(3):E12-E24
Successful visual prostheses require stable, long‐term attachment. Epiretinal prostheses, in particular, require attachment methods to fix the prosthesis onto the retina. The most common method is fixation with a retinal tack; however, tacks cause retinal trauma, and surgical proficiency is important to ensure optimal placement of the prosthesis near the macula. Accordingly, alternate attachment methods are required. In this study, we detail a novel method of magnetic attachment for an epiretinal prosthesis using two prostheses components positioned on opposing sides of the retina. The magnetic attachment technique was piloted in a feline animal model (chronic, nonrecovery implantation). We also detail a new method to reliably control the magnet coupling force using heat. It was found that the force exerted upon the tissue that separates the two components could be minimized as the measured force is proportionately smaller at the working distance. We thus detail, for the first time, a surgical method using customized magnets to position and affix an epiretinal prosthesis on the retina. The position of the epiretinal prosthesis is reliable, and its location on the retina is accurately controlled by the placement of a secondary magnet in the suprachoroidal location. The electrode position above the retina is less than 50 microns at the center of the device, although there were pressure points seen at the two edges due to curvature misalignment. The degree of retinal compression found in this study was unacceptably high; nevertheless, the normal structure of the retina remained intact under the electrodes. 相似文献
62.
目的:探讨前置胎盘不同附着位置对剖宫产后再次妊娠母婴结局的影响。方法回顾性分析本院2011年1月~2013年12月收治的80例剖宫产后再次妊娠合并前置胎盘患者的临床资料,将胎盘附着于前壁的患者分为实验组,附着于后壁的患者为对照组,比较两组患者的一般资料、新生儿情况、妊娠结局和并发症发生情况。结果实验组患者胎盘植入、胎盘粘连、急诊剖宫产、子宫切除、弥散性血管内凝血、产后出血、出血量〉1000 ml以及早产发生率均显著高于对照组,差异有统计学意义(P〈0.05)。结论剖宫产后再次妊娠产妇合并前置胎盘,胎盘附着于前壁时妊娠结局较后壁差,应提前确认附着位置以改善妊娠结局。 相似文献
63.
Human respiratory syncytial virus (HRSV) is the main cause of severe respiratory illness in young children and elderly people. We investigated the genetic characteristics of the circulating HRSV subgroup A (HRSV-A) to determine the distribution of genotype ON1, which has a 72-nucleotide duplication in attachment G gene. We obtained 456 HRSV-A positive samples between October 2008 and February 2013, which were subjected to sequence analysis. The first ON1 genotype was discovered in August 2011 and 273 samples were identified as ON1 up to February 2013. The prevalence of the ON1 genotype increased rapidly from 17.4% in 2011–2012 to 94.6% in 2012–2013. The mean evolutionary rate of G protein was calculated as 3.275 × 10−3 nucleotide substitution/site/year and several positively selected sites for amino acid substitutions were located in the predicted epitope region. This basic and important information may facilitate a better understanding of HRSV epidemiology and evolution. 相似文献
64.
65.
Attachment theory provides a framework for understanding individual differences in chronic interpersonal stress. Attachment anxiety, a type of relationship insecurity characterized by worry about rejection and abandonment, is a chronic interpersonal stressor. Stress impacts cellular immunity, including herpesvirus reactivation. We investigated whether attachment anxiety was related to the expression of a latent herpesvirus, Epstein–Barr virus (EBV), when individuals were being tested for breast or colon cancer and approximately 1 year later. Participants (N = 183) completed a standard attachment questionnaire and provided blood to assess EBV viral capsid antigen (VCA) IgG antibody titers. Individuals with more attachment anxiety had higher EBV VCA IgG antibody titers than those with less attachment anxiety. The strength of the association between attachment anxiety and antibody titers was the same at both assessments. This study is the first to show an association between latent herpesvirus reactivation and attachment anxiety. Because elevated herpesvirus antibody titers reflect poorer cellular immune system control over the latent virus, these data suggest that high attachment anxiety is associated with cellular immune dysregulation. 相似文献
66.
67.
Background
In China, research on the relation of mother–infant attachment to children's development is scarce.Aims
This study sought to investigate the relation of mother–infant attachment to attachment, cognitive and behavioural development in young children.Study design
This study used a longitudinal study design.Subjects
The subjects included healthy infants (n = 160) aged 12 to 18 months.Outcome measures
Ainsworth's “Strange Situation Procedure” was used to evaluate mother–infant attachment types. The attachment Q-set (AQS) was used to evaluate the attachment between young children and their mothers. The Bayley scale of infant development-second edition (BSID-II) was used to evaluate cognitive developmental level in early childhood. Achenbach's child behaviour checklist (CBCL) for 2- to 3-year-olds was used to investigate behavioural problems.Results
In total, 118 young children (73.8%) completed the follow-up; 89.7% of infants with secure attachment and 85.0% of infants with insecure attachment still demonstrated this type of attachment in early childhood (κ = 0.738, p < 0.05). Infants with insecure attachment collectively exhibited a significantly lower mental development index (MDI) in early childhood than did infants with secure attachment, especially the resistant type. In addition, resistant infants were reported to have greater social withdrawal, sleep problems and aggressive behaviour in early childhood.Conclusion
There is a high consistency in attachment development from infancy to early childhood. Secure mother–infant attachment predicts a better cognitive and behavioural outcome; whereas insecure attachment, especially the resistant attachment, may lead to a lower cognitive level and greater behavioural problems in early childhood. 相似文献68.
Objectives
This in vitro study should assess the fracture resistance of veneered zirconia-based crowns with either luted or fused veneer.Methods
Thirty-two identical zirconia frameworks (IPS e.max ZirCAD; Ivoclar/Vivadent), were constructed (inLab 3.80; Sirona Dental Systems). All frameworks were veneered with CAD/CAM-fabricated lithium disilicate ceramic (IPS e.max CAD; Ivoclar/Vivadent). For half the crowns (n = 16) the veneer was luted to the framework (Multilink Implant; Ivoclar/Vivadent); for the other it was fused (IPS e.max Crystall./Connect; Ivoclar/Vivadent). Half of the specimens were then loaded until failure without artificial aging; the other half underwent artificial aging before assessment of the ultimate load. To compare the two techniques further, finite element analysis (FEA) and fractographic assessment using SEM and EDX analysis were conducted. Statistical assessment was performed by use of non-parametric tests.Results
Initial fracture forces were higher in the fusion group (mean: 1388 ± 190 N versus 1211 ± 158 N). All specimens were insensitive to artificial aging. FEA showed that tensile stresses in the veneer at the frame–veneer interface were much higher for crowns with luted veneer; this may be the reason for their lower fracture resistance. Fractographic analysis revealed that both fused and luted specimens had cohesive and adhesive fracture patterns which resulted in partial delamination of the veneer.Significance
Fused crowns are superior to luted crowns. Comparison of fracture resistance with the maximum loads which may occur clinically (Fmax = 600 N on one tooth) suggests both techniques might be used clinically, however. 相似文献69.
《The journal of sexual medicine》2020,17(7):1370-1382
BackgroundDespite the fact that childhood sexual abuse can affect a survivor's sexual functioning in adulthood, few studies have examined survivors' adult sexual functioning from the perspective of attachment theory.AimThe present study sought to examine how sexual abuse in childhood might shape the associations between attachment insecurities and sexual functioning among adults.MethodsThe study sample consisted of 265 participants (166 women and 99 men), 45 (16.9%) of whom were classified as survivors of childhood sexual abuse. Participants completed an online questionnaire about their history of childhood sexual abuse, attachment insecurities, and sexual functioning over the past 6 months.OutcomesThe findings of the present study suggest that attachment insecurities may have unique implications for sexual functioning among survivors of childhood sexual abuse.ResultsFindings indicated that a history of childhood sexual abuse significantly moderated the associations between attachment insecurities and sexual functioning. Whereas the effect of attachment avoidance in predicting sexual desire was not significant among nonabused participants, it was significant among survivors; specifically, higher levels of attachment avoidance predicted lower levels of sexual desire. A different pattern was found for attachment anxiety. Although attachment anxiety did not predict vaginal lubrication/penile erection among nonabused participants, it had significant effects among survivors; specifically, higher levels of attachment anxiety predicted higher levels of vaginal lubrication/penile erection.Clinical TranslationFindings from the present study may help facilitate sex therapy interventions for childhood sexual abuse survivors, from an attachment theory perspective.Strengths & LimitationsThe study included a nonclinical, convenience sample and used self-report measures, which are highly subjective and increase the possibility of social-desirability biases. However, on the plus side, it relied on simple, short, self-report questionnaires that are accessible and can be easily used by professionals to examine a survivor's current condition relative to any of the variables, establish intervention goals, and evaluate treatment.ConclusionA history of childhood sexual abuse is related to 2 opposite patterns of association between attachment insecurity (depending on type) and sexual functioning.Gewirtz-Meydan A, Lahav Y. Sexual Functioning Among Childhood Sexual Abuse Survivors From an Attachment Perspective. J Sex Med 2020;17:1370–1382. 相似文献
70.
《The journal of sexual medicine》2020,17(7):1383-1394
BackgroundAttachment and intimacy play an important role in shaping sexual and relational experiences. Yet, their interrelation has rarely been investigated in the context of sexual problems and never been tested in Saudi Arabian women.AimThe present study examined the interrelations of attachment orientation and sexual function, distress, satisfaction, and relational satisfaction in a sample of Saudi Arabian women and explored whether this link can be explained by 2 important aspects of (sexual) intimacy, namely perceived partner responsiveness (PPR) and sexual assertiveness.MethodThis is a cross-sectional, observational study in a sample of 50 heterosexual women with sexual problems and 50 control women without problems, who completed an Arabic version of questionnaires on attachment orientation, sexual assertiveness, PPR, relationship satisfaction, sexual satisfaction, sexual distress, and sexual function.ResultsWe found that both attachment anxiety and sexual refusal showed a significant association with the level of sexual function, sexual distress, and sexual satisfaction (P < .01) in the clinical group. No mediating effects of sexual refusal were found. In the control group, sexual function, sexual distress, and sexual satisfaction were predicted by attachment avoidance (P < .01). Level of sexual function was also predicted by sexual initiation (P < .05). PPR fully mediated the association between attachment anxiety and relational satisfaction in the clinical group (P < .01), while in the control group the link between attachment avoidance and relational satisfaction was only partially mediated by PPR (P < .01).Strengths & LimitationsThis study offers unique information on relational and sexual functioning in a culture in which sexual expression and intimate behavior are restricted, particularly in women.Clinical ImplicationsPerceiving the partner as being more responsive is an important target of intervention to increase satisfaction with the relationship.ConclusionsOur results suggest that attachment anxiety and low sexual assertiveness, as indicated by lower tendencies to refuse sex when not desired, play a significant role in predicting negative sexual experiences in women who cope with sexual difficulties.Attaky A, Kok G, Dewitte M. Attachment Insecurity and Sexual and Relational Experiences in Saudi Arabian Women: The Role of Perceived Partner Responsiveness and Sexual Assertiveness. J Sex Med 2020;17:1383–1394. 相似文献