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11.
Recent studies investigating possible causes of male subfertility have largely focused on how lifestyle or environmental factors impact on the process of spermatogenesis. Markedly, fewer studies have investigated those risk factors that result in reduced sperm quality, such as poor sperm motility. The speed at which sperm swim is a major predictor of fertility and is extremely variable in human populations. It has been hypothesized that offspring sex may be adaptively manipulated to maximize the offspring''s reproductive fitness (e.g., parents with genes for good male fertility traits, such as high sperm speed, would produce primarily sons and fewer daughters because the offspring will inherit advantageous male fertility genes). Conversely, parents with poor male fertility genes would produce primarily daughters. We tested whether there was an association between how fast a man''s sperm swam and the sex bias of his siblings in a sample of men attending clinic for fertility investigations with their partner and with a wide range of semen characteristics, including sperm speed. We found that the sex bias of a man''s siblings is associated with his sperm speed; men with female-biased siblings had significantly slower sperm (judged using computer-assisted sperm analysis (CASA)) than men from male-biased sibships. This observation suggests family composition is an important factor that needs to be considered in future epidemiological and clinical studies of human fertility.  相似文献   
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OBJECTIVES:: The aim of this study was to determine whether visualization of the back influenced parameters of movement-related pain in people with chronic nonspecific low back pain. METHODS:: We used a randomized cross-over experiment in which 25 participants performed repeated lumbar spine movements under 2 conditions. In the visual feedback condition, patients were able to visualize their back as it moved by the use of mirrors. In the control condition, the mirror was covered so no visualization of the back was possible. RESULTS:: The average postmovement pain intensity after participants had moved with visual feedback was less (35.5±22.8 mm) than when they moved without visual feedback (44.7±26.0 mm). This difference was statistically significant (mean difference=9.3, 95% confidence interval: 2.8-15.7 F(1,22)=8.82, P=0.007). The average time to ease after participants had moved with visual feedback was shorter (44.5 s±53.8) than when they moved without visual feedback (94.4 s±80.7). This difference was also statistically significantly (mean difference=49.9, 95% confidence interval: 19.3-80.6, F(1,22)=8.82, P=0.003). DISCUSSION:: Patients with chronic nonspecific low back pain reported less increase in pain and faster resolution of pain when moving in an environment that enabled them to visualize their back. This is consistent with emerging research on the use of mirror visual feedback in other long-standing pain problems and suggests that similar lines of inquiry may be worth pursuing in the chronic nonspecific low back pain population.  相似文献   
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IntroductionThe lymphomas (Hodgkin's lymphoma [HL] and non-Hodgkin's lymphoma [NHL]) are among the most common cancers affecting men under 45 years. Survival rates are now excellent, but treatment is associated with a number of side effects including sexual dysfunction with potential implications for compromised quality of life (QoL).AimsTo address the (i) prevalence of sexual dysfunction among lymphoma survivors relative to the general population, survivors of other cancers, and in survivors of HL and NHL; and (ii) relationships between sexual functioning and disease and treatment, demographic, and psychological variables.MethodsInclusion criteria were quantitative studies that focused on adult male survivors of lymphoma and included a comparison group and presented results separately for HL and NHL. Standardized systematic searches were used. Information about design, sample size, age, time since diagnosis, type of treatment, comparison group, measures, and findings were extracted from eligible studies.ResultsTen articles met the inclusion criteria, of which, nine included patients with HL only, and one included patients with HL or NHL. Sexual function was compromised relative to the general population, better than testicular cancer survivors, and worse than leukemia survivors. Depression was consistently associated with sexual dysfunction. There was evidence that chemotherapy, relapse, reduced testosterone levels, older age at survey, and worse physical QoL were associated with worse sexual function.ConclusionsConclusions are limited by methodological issues including lack of utilization of standardized measures of sexual function and longitudinal research. Even so, there is evidence of sexual dysfunction among lymphoma survivors. Clinicians need to be sensitive to these issues. Future longitudinal work is necessary to determine the likelihood of recovery. Arden-Close E, Eiser C, and Pacey A. Sexual functioning in male survivors of lymphoma: a systematic review. J Sex Med 2011;8:1833-1840.  相似文献   
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Natural killer (NK) and some T cells express killer cell immunoglobulin-like receptors (KIRs), which interact with HLA class I expressed by target cells and consequently regulate cytolytic activity. The number of KIR loci can vary and so a range of genetic profiles is observed. We have determined the KIR genetic profiles from one African (n = 62) and two South Asian (n = 108, n = 78) populations. Several of the KIRs are present at significantly different frequencies between the two major ethnic groups (eg KIR2DS4 gene frequency 0.82 African, 0.47 S Asian. Pc < 1 x 10(-6)) and this is due to uneven distribution of two KIR haplotype families 'A' and 'B'. All three populations described here displayed a greater degree of diversity of KIR genetic profiles than other populations investigated, which indicates further complexity of underlying haplotypes; in this respect we describe two individuals who appear homozygous for a large deletion including the previously ubiquitous 2DL4. We have also reanalysed three populations that we studied previously, for the presence of a KIR which is now known to be an indicator of the 'B' haplotype. South Asians had the highest overall frequencies of all KIR loci characteristic of 'B' haplotypes (Pc < 0.0001 to < 0.004). Furthermore, gene frequency independent deviances in the linkage disequilibrium were apparent between populations.  相似文献   
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The purpose of this study was to investigate the effects of peripheral afferent stimuli on the synchrony between brain and muscle activity as estimated by corticomuscular coherence (CMC). Electroencephalogram (EEG) from sensorimotor cortex and electromyogram (EMG) from two intrinsic hand muscles were recorded during a key grip motor task, and the modulation of CMC caused by afferent electrical and mechanical stimulation was measured. The particular stimuli used were graded single-pulse electrical stimuli, above threshold for perception and activating cutaneous afferents, applied to the dominant or non-dominant index finger, and a pulsed mechanical displacement of the gripped object causing the subject to feel as if the object may be dropped. Following electrical stimulation of the dominant index finger, the level of β-range (14–36 Hz) CMC was reduced in a stimulus intensity-dependent fashion for up to 400 ms post-stimulus, then returned with greater magnitude before falling to baseline levels over 2.5 s, outlasting the reflex and evoked changes in EMG and EEG. Subjects showing no baseline β-range CMC nevertheless showed post-stimulus increases in β-range CMC with the same time course as those with baseline β-range CMC. The mechanical stimuli produced similar modulation of β-range CMC. Electrical stimuli to the non-dominant index finger produced no significant increase in β-range CMC. The results suggest that both cutaneous and proprioceptive afferents have access to circuits generating CMC, but that only a functionally relevant stimulus produces significant modulation of the background β-range CMC, providing further evidence that β-range CMC has an important role in sensorimotor integration.  相似文献   
17.
Introduction. Laws, Kondel, and McKenna (1999) previously reported a case study analysis of a schizophrenic patient (TC) with severe formal thought disorder (FTD). Examining consistency across item and modality of input, Laws et al. documented an impairment of access to semantic knowledge in TC. Method. Following substantial improvement in his FTD, we readministered the same extensive battery of neuropsychological tests tapping semantic memory functioning.Results. Whilst TC's naming remained relatively good, it also became more consistent across both time and modality. Tasks tapping language comprehension and understanding of semantic association revealed some significant improvements. Nevertheless, TC showed a residual propensity to verify false information.Conclusion. Improvement in FTD in schizophrenia was accompanied by a better and more stable semantic memory performance in TC. The findings are consistent with, and expand upon the original suggestion that thought disorder reflects disorganised access to semantic memory.  相似文献   
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Intercellular adhesion molecule‐1 (ICAM‐1) gene polymorphisms have been implicated in the susceptibility to inflammatory diseases, including multiple sclerosis and inflammatory bowel disease. The expression of both soluble and tissue ICAM‐1 is increased in Behçet’s disease (BD) but the contribution of ICAM‐1 gene polymorphisms to this disease remains unknown. Associations with BD have been reported for genes within the MHC, including HLA‐B51, TNF and MICA, but the role of non‐MHC genes in BD remains largely unexplored. We have investigated the frequency of the R/G 241 and K/E 469 ICAM‐1 gene polymorphisms in 83 patients with BD disease and 103 healthy controls, all of Palestinian and Jordanian descent, and demonstrated an association between BD and the ICAM‐1 E469 allele (Pc = 0.046, OR = 2.1). Among patients, no association was found between the presence of ocular disease and ICAM‐1 polymorphisms. While the functional correlate of this polymorphism remains unclear, this finding indicates that a genetic polymorphism in the ICAM‐1 gene domain, which is independent of the MHC, may contribute to disease.  相似文献   
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Mental health comorbidities are prevalent and problematic in patients with seizures but often suboptimally managed. To address common gaps in care, the Integrated Mental Health Care Pathways Task Force of the International League Against Epilepsy (ILAE) Psychiatry Commission was tasked with providing education and guidance on the integration of mental health management (e.g., screening, referral, treatment) into routine seizure care. This report aims to describe a variety of established services in this area, with a specific focus on psychological care models. Services were identified by members of the ILAE Psychiatry Commission and authors of psychological intervention trials in epilepsy. A total of eight services met inclusion criteria and agreed to be showcased. They include three pediatric and five adult services located across four distinct ILAE regions (Europe, North America, Africa, Asia Oceania). The report describes the core operations, known outcomes, and implementation factors (i.e., barriers and facilitators) of these services. The report concludes with a set of practical tips for building successful psychological care services within seizure settings, including the importance of having local champions, clearly defining the scope of the service, and establishing sustainable funding models. The breadth of exemplars demonstrates how models tailored to the local environment and resources can be implemented. This report is an initial step to disseminate information regarding integrated mental health care within seizure care settings. Future work is needed to systematically examine both psychological and pharmacological care models and to further establish the evidence base in this area, especially around clinical impact, and cost-effectiveness.  相似文献   
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