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51.
Cognitive-behavioural models of chronic pain contend that appraisals of harm affect the individual's response to pain. It has been suggested that fear of pain and/or anxiety sensitivity predispose individuals to chronicity. According to this view, pain is maintained through hypervigilance towards painful sensations and subsequent avoidance. The present study investigates the nature of cognitive biases in chronic pain patients. A sample of 169 consecutive patients referred to a specialist pain management centre participated in the study. Questionnaires measuring different aspects of pain and a computerised version of the Dot-Probe Task were administered. Four types of words related to different dimensions of pain and matched, neutral words were used as stimuli. Reaction times in response to the stimuli were recorded. A factorial design 3 x 4 x 2 x 2 and ANOVAs were employed to analyse the data. Chronic pain patients showed a cognitive bias to sensory pain words relative to affective, disability, and threat-related words. However, contrary to expectations, those high in fear of pain responded more slowly to stimuli than those less fearful of pain. These results suggest that patients with chronic pain problems selectively attend to sensory aspects of pain. However, selective attention appears to depend upon the nature of pain stimuli. For those who are highly fearful of pain they may not only selectively attend to pain-related information but have difficulty disengaging from that stimuli. Theoretical and clinical implications of the data are discussed. 相似文献
52.
In electrical impedance tomography surface measurements of voltages and currents are recorded and the image reconstruction algorithm uses this set of boundary data to estimate internal electrical properties of the region under investigation. Therefore correct and accurate modelling of the current and voltage distributions (forward model) is an essential part of any reconstruction method. In this paper, we explored the root cause of a boundary layer effect in the reconstructed conductivity map and found it to be an artefact arising from 2D to 3D data-model mismatch within the imaging algorithm. We propose a data calibration scheme that improves the reconstruction results by removing these boundary or edge effects. We present both two-dimensional and three-dimensional images for agar phantoms using this data calibration scheme which are markedly better than their counterparts recovered when the measurement data are not calibrated with the procedure outlined herein. 相似文献
53.
Marjan Akhavan Amjadi Masoumeh Simbar Seyyed Ali Hosseini Farid Zayeri 《Sexuality and disability》2017,35(3):313-330
Sexual health as an important aspect of reproductive health, is a foundation for physical and emotional health which also affects couples and families’ wellbeing. Furthermore, disability could impact couple’s sexual relationships. Studies show that people with physical disability receive less sexual education which in turn exposes them to a higher risk for sexually transmitted infections. This qualitative study explored the sexual needs of women with spinal cord injury (SCI) aged 18–55 years old living in Tehran. In depth and individual semi-structured interviews were hold for data collection until data saturation was reached. They were recruited from the Organization of Welfare and Protection Center of Spinal Cord Disables of Iran. In this study 23 individuals were chosen using purposive sampling. The collected data was analyzed using the content analysis approach suggested by Graneheim and Lundman. The sexual health needs of women with SCI was explained in two themes and nine categories. The themes were “physical rehabilitation” and “couples’ sexual consultation”. The categories of the first theme were “resolving physical problems contributing to sexual relationships” and “complementary medicine application”. The categories of the second theme were “the husband’s emotional support”, “concentration”, “protecting sexual health”, “the need for having sexual relationships”, “diminishing factors for unpleasant sexual relationships”, “paying attention to wife’s readiness to start sexual relationships” and “decreasing factors that suppress spouse’s sexual desire”. This study showed that women with spinal cord injury require sexual rehabilitation. They overcome their physical problems with the help of complementary medicine and sexual counselling around the aforementioned categories for promoting the quality of their sexual health. 相似文献
54.
55.
Aluminium is an environmental pollutant which induces oxidative stress, while silymarin is a potent antioxidant. This study was conducted to investigate the possible protective effects of silymarin on adverse effects of aluminium chloride on vital sperm parameters as well as its effects on oxidative stress markers in human spermatozoa. Human spermatozoa were divided into 5 groups as follows: (a) spermatozoa at 0 hr; (b) spermatozoa at 180 min (control); (c) spermatozoa treated with aluminium chloride; (d) spermatozoa treated with silymarin + aluminium chloride; and (e) spermatozoa treated with silymarin. The sperm samples were used to assess sperm vital parameters such as acrosome and plasma membrane integrity, viability, mitochondrial membrane potential (MMP) and motility as well as sperm malondialdehyde (MDA) level and the total antioxidant capacity. The percentage of acrosome and plasma membrane integrity, viability, MMP, motility and the total antioxidant capacity of spermatozoa treated with aluminium chloride significantly decreased compared with control group, while the level of MDA significantly increased compared with the control group. In the silymarin + aluminium chloride group, silymarin could significantly compensate the adverse effects of aluminium chloride on these parameters. Administration of silymarin alone significantly increased the percentage of acrosome and plasma membrane integrity, viability, motility and total antioxidant capacity, while significantly reduced MDA levels compared with the control group. Aluminium chloride by inducing oxidative stress exerts disastrous effects on the vital parameters of human spermatozoa and silymarin, as a potent antioxidant, could reverse the effects of aluminium chloride on these parameters. 相似文献
56.
Controversy surrounding disclosure among the recipients of assisted reproductive donation procedures is escalating worldwide, but little research has been conducted in this topic. The purpose of this qualitative study was to explore the experiences of infertile couples undergoing assisted reproductive donation procedures. In this exploratory qualitative study, 32 patients (nine couples and 14 women) who were candidates to use donor eggs, donor embryos or surrogacy, and 5 members of infertility treatment team including gynaecologists, midwives and psychologist (total 37) were purposively selected from the Montaserieh Infertility Research Centre at Mashhad, Iran in 2012 and interviewed using a semi-structured in-depth method. Data were analysed using conventional qualitative content analysis with MAXqda software. One overarching theme, entitled ‘experiencing uncertainty surrounding the disclosure to others’ was identified from the data. This theme contained two subthemes including ‘Couples’ decisions to not disclose to others’ and ‘Couples’ decisions to disclose to others’. Five categories formed the first subtheme, and the second subtheme emerged from four categories which are discussed in this paper. The main reason for secrecy was concern over societal negative views about assisted reproductive donation procedures. This worry deprived the couples from support from family and friends and as a result requires them to tolerate psychological pressure when using such procedures. 相似文献
57.
Farzaneh Fesahat Seyed Mehdi Kalantar Mohammad Hasan Sheikhha Hojjatollah Saeedi Fatemeh Montazeri Razieh Dehghani Firouzabadi Mohammad Ali Khalili 《European journal of medical genetics》2018,61(4):235-241
Aneuploidy is of great relevance to embryo selection, as it represents one of the important causes of implantation failure. Furthermore, immature oocytes, retrieved during gonadotrophin-stimulated IVF cycles, are generally discarded in clinics; whereas, there was no detectable comprehensive evidence on higher rates of aneuploidy based on maturity status on the day of oocyte retrieval. As well, the correlation between embryo morphology on aneuploidy remains unclear. The aim was to evaluate the developmental and genetic integrity of human preimplantation embryos from rescue in-vitro matured MII stage oocytes as well as in vivo matured oocytes. 541 rescue in-vitro matured oocytes as case as well as 659 in-vivo matured oocytes as control were used for the developmental assay. Finally, 121 cleaved embryos with good quality were analyzed by FISH technique for the detection of chromosomes X, Y, 13, 15, 16, 18, 21 and 22. The fertilization rates were 61.62% and 61.76% in case and control groups, respectively. Also, embryo formation rates of 89.1% vs. 92.2% were recorded for case and control groups, respectively. Good quality embryos on day 3 were 62.54% in case and 68.36% in control groups. There were insignificant differences in fertilization, embryo formation and quality between the groups. Total abnormality in 35 of the 60 embryos was 58.5% in case and 62.3% in control (p < 0.05). There were significant differences between aneuploidy rates of embryos using only sex chromosome preimplantation genetic screening (PGS) and sex chromosome in combination with autosomal chromosomes PGS in case (58.5% vs 28.3%, p = 0.000) and control groups (62.3% vs 21.3%; p = 0.000). The results demonstrated that a high proportion of good quality embryos were aneuploid in both patient groups with no obvious increase in aneuploidies as a result of rescue IVM application. Furthermore, the morphological characteristics of embryos do not completely consistent with chromosomal content. Despite the Rescue IVM is currently not a routine procedure in association with IVF, our finding suggested a viable option for young infertile women facing cancellation of their IVF treatment due to ovarian over-response or resistance factors as well as patients with low functional ovarian reserve considering good quality of embryos from rescue IVM-MII oocytes. 相似文献
58.
Arash Arya Majid Haghjoo Zahra Emkanjoo Mohammad Reza Dehghani Mohammad Ali Sadr-Ameli 《Journal of interventional cardiac electrophysiology》2006,17(1):59-63
Objective We conducted this study to compare the rate of ≥1 inappropriate therapy between ICDs from two manufacturers which use different
discriminatory protocols.
Method One hundred sixty two patients (mean age 58 ± 13 years, 126 male) who received ICDs between January 2001 and 2005 were included
in the study. Clinical, electrocardiographic, and ICD stored data and electrograms were collected and analyzed. Immediately
after implantation all the detection and discrimination criteria were activated with the nominal values in order to compare the two discriminatory protocols under the default manufacturer’s settings.
Results During the follow up period of 14.3 ± 10 months, 49 (30%) patients received ≥1 inappropriate ICD therapy. The rate of ≥1 inappropriate
ICD therapy in manufacturer A and B ICDs was 26% (n = 29) and 41% (n = 20), respectively. Comparing the rate of ≥1 inappropriate ICD therapy between the two groups by Kaplan–Meier analysis and
the log rank test resulted in P = 0.04.
Conclusion Having all discriminatory variables activated with the nominal values, discriminatory performance differs between the two manufacturers. Further larger-scale studies are warranted to prospectively
compare the performance of various available ICDs’ discriminatory protocols, and define the optimum combination of discriminators in each ICD to decrease the rate of inappropriate therapy. 相似文献
59.
60.
In the mammalian pineal gland, the rhythm in melatonin biosynthesis depends on the norepinephrine (NE)-driven regulation of arylalkylamine N-acetyltransferase (AANAT), the penultimate enzyme of melatonin biosynthesis. A recent study showed that phytocannabinoids like tetrahydrocannabinol reduce AANAT activity and attenuate NE-induced melatonin biosynthesis in rat pineal glands, raising the possibility that an endocannabinoid system is present in the pineal gland. To test this hypothesis, we analyzed cannabinoid (CB) receptors and specific enzymes for endocannabinoid biosynthesis or catabolism in rat pineal glands and cultured pinealocytes. Immunohistochemical and immunoblot analyses revealed the presence of CB1 and CB2 receptor proteins, of N-acyl phosphatidyl ethanolamine hydrolyzing phospholipase D (NAPE-PLD), an enzyme catalyzing endocannabinoid biosynthesis and of fatty acid amide hydrolase (FAAH), an endocannabinoid catabolizing enzyme, in pinealocytes, and in pineal sympathetic nerve fibers identified by double immunofluorescence with an antibody against tyrosine hydroxylase. The immunosignals for the CB2 receptor, NAPE-PLD, and FAAH found in pinealocytes did not vary under a 12 hr light:12 hr dark cycle. The CB1 receptor immunoreaction in pinealocytes was significantly reduced at the end of the light phase [zeitgeber time (ZT) 12]. The immunosignal for NAPE-PLD found in pineal sympathetic nerve fibers was reduced in the middle of the dark phase (ZT 18). Stimulation of cultured pinealocytes with NE affected neither the subcellular distribution nor the intensity of the immunosignals for the investigated CB receptors and enzymes. In summary, the pineal gland comprises indispensable compounds of the endocannabinoid system indicating that endocannabinoids may be involved in the control of pineal physiology. 相似文献