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81.
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Infertility is estimated to affect up to 15% of couples of reproductive age. Among the male factors, globozoospermia (also called round‐headed sperm syndrome) is a rare type of teratozoospermia accounting for <0.1% of male infertility. Lack of acrosome, whose production is a postmeiotic event in spermatogenesis, and round sperm head are its main characteristics. The acrosomeless spermatozoon is unable to go through the zona pellucida and fuse with the oolemma of the oocyte, and fertilisation failures have been attributed to a deficiency in oocyte activation capacity, even when intracytoplasmic sperm injection (ICSI) is attempted. The pathogenesis of this anomaly is still unclear but genetic factors are likely to be involved. DNA fragmentation rate has been reported for 16 globozoospermic males, usually using the terminal uridine nick‐end labelling (TUNEL) assay. Most of the patients had a DNA fragmentation index (DFI) higher than that in fertile men. The rate of aneuploidy for some specific chromosomes was increased in 12 among the 26 globozoospermic males reported in the literature. The same results (high DFI and aneuploidy rates) were observed in infertile males compared to fertile men, notably in those with oligoasthenozoospermia or teratozoospermia, independently of the origins. Mutations or deletions in three genes, SPATA16, PICK1 and DPY19L2, have been shown to be responsible for globozoospermia. Proteins coded by the first two genes localise to the Golgi apparatus and the proacrosomal granules that are transported in the acrosome. It is likely that other proteins involved in the acrosome formation remain to be identified.  相似文献   
83.
The risk of fractures after kidney transplantation is high. Hyperparathyroidism frequently persists after successful kidney transplantation and contributes to bone loss, but its impact on fracture has not been demonstrated. This longitudinal study was designed to evaluate hyperparathyroidism and its associations with mineral disorders and fractures in the 5 posttransplant years. We retrospectively analyzed 143 consecutive patients who underwent kidney transplantation between August 2004 and April 2006. The biochemical parameters were determined at transplantation and at 3, 12 and 60 months posttransplantation, and fractures were recorded. The median intact parathyroid hormone (PTH) level was 334 ng/L (interquartile 151–642) at the time of transplantation and 123 ng/L (interquartile 75–224) at 3 months. Thirty fractures occurred in 22 patients. The receiver operating characteristic (ROC) curve analysis for PTH at 3 months (area under the ROC curve = 0.711, p = 0.002) showed that a good threshold for predicting fractures was 130 ng/L (sensitivity = 81%, specificity = 57%). In a multivariable analysis, independent risk factors for fracture were PTH >130 ng/L at 3 months (adjusted hazard ratio [AHR] = 7.5, 95% CI 2.18–25.50), and pretransplant osteopenia (AHR = 2.7, 95% CI 1.07–7.26). In summary, this study demonstrates for the first time that persistent hyperparathyroidism is an independent risk factor for fractures after kidney transplantation.  相似文献   
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Journal of Autism and Developmental Disorders - This study examined emergency department (ED) utilization by adolescents and young adults, 12–30&nbsp;years of age (AYA) with autism...  相似文献   
86.
Anxiety disorders are the most common psychiatric disorder of childhood, and are associated with high risk for development of future psychopathology. Yet, pediatric anxiety disorders continue to be under diagnosed in primary care, leaving many children untreated. Pediatricians in primary care settings are in a unique position to detect child anxiety within the context of well-child visits. While important efforts are currently under way, such as increased behavioral screening, one of the most important challenges is that pediatricians do not receive an adequate level of training in the evaluation, management, and treatment of anxiety disorders. We review recent assessment initiatives in this area and call for increased efforts to promote early detection in primary care and reduce potential barriers for pediatricians, consistent with the movement toward integrated behavioral health models. Finally, we describe a current initiative that utilizes collaboration between psychologists and pediatric faculty to train pediatric residents to detect, diagnose, counsel, and refer young children with anxiety.  相似文献   
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We examined social support as a protective factor in the relationship between lifetime exposure to traumatic events and Post-Traumatic Stress Disorder (PTSD) symptomatology among urban women. Seventy-six women who sought care in a trauma center for injuries from physical or sexual violence completed an interview. When tangible support, rather than total social support, and the interaction of tangible support and lifetime trauma were tested, tangible support moderated the relationship between lifetime trauma and PTSD. Given the complex etiology of lifetime trauma, risk for future trauma and the health needs of women who have experienced trauma, a broader range of intervention strategies that include attention to tangible support need to be developed and evaluated.  相似文献   
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OBJECTIVE: The current recommendation that patients infected with HIV-1 be treated early is based on little evidence. We examined whether the early initiation of antiretroviral treatment affects residual HIV-1 viraemia. METHODS: Viraemia was measured using an assay with a detection limit of 3 HIV-1 RNA copies/ml in drug-naive patients who started antiretroviral therapy at the time of primary HIV-1 infection (PHI) (n = 10), during chronic infection without immune suppression (CD4 cell counts > or = 500/mm3; median 577) (n = 10), or after immune suppression developed (CD4 cell counts < 500/mm3; median 113) (n = 21). RESULTS: In 249 samples collected 24 to 120 weeks after treatment initiation, the mean proportion of samples with HIV-1 RNA levels of less than 3 copies/ml was 75% for PHI patients compared with 32 and 8% for immunocompetent and immunosuppressed chronically infected patients, respectively. Fifty per cent of PHI patients, but none of the chronically infected patients, had persistently fewer than 3 HIV-1 RNA copies/mL. PHI patients had lower residual HIV-1 RNA levels than chronically infected patients, and immunocompetent patients had lower residual HIV-1 RNA levels than immunosuppressed patients (all pairwise, P< 0.001). The mean residual HIV-1 RNA level was independently associated with the initiation of therapy during PHI and baseline CD4 cell counts (P < 0.001 for both associations). CONCLUSION: Viraemia levels are associated with clinical progression and predict virological treatment failure. The initiation of antiretroviral therapy at the time of PHI and while CD4 cell counts are high results in lower residual viraemia. These results support early antiretroviral therapy in HIV-1-infected patients.  相似文献   
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