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31.
The androgen insensitivity syndrome is a heterogeneous disorder with a wide spectrum of phenotypic abnormalities, ranging from complete female to ambiguous forms that more closely resemble males. The primary abnormality is a defective androgen receptor protein due to a mutation of the androgen receptor gene. This prevents normal androgen action and thus leads to impaired virilisation. A point mutation of the androgen receptor gene affecting two siblings with partial androgen insensitivity syndrome is described. One had cliteromegaly and labial fusion and was raised as a girl, whereas the other sibling had micropenis and penoscrotal hypospadias and was raised as a boy. Both were shown to have the arginine 840 to cysteine mutation. The phenotypic variation in this family is thus dependent on factors other than abnormalities of the androgen receptor gene alone.  相似文献   
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Systemic Lupus Erythematosus: Perinatal and Neonatal Implications   总被引:2,自引:0,他引:2  
Systemic lupus erythematosus (SLE) is a chronic autoimmune disorder that can affect almost all organ systems in the body. It is most common in women of childbearing age and may cause multiple peripartum complications. This article reviews the pathophysiology of SLE and the effects of SLE on fertility and pregnancy. The complexities of managing a pregnant patient with SLE are reviewed, and the importance of interdisciplinary collaboration discussed, as well as the effects of SLE on the fetus and a review of neonatal lupus erythematosus. Finally, a case report of a pregnant patient with SLE with challenging clinical management issues is presented.  相似文献   
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The authors report the results obtained in 16 patients affected with displaced fracture of the acetabulum treated surgically and mobilized passively immediately after surgery by means of a continuous passive mobilization apparatus for the hip. The age of the patients at the time of trauma ranged from 21 to 54 years. The posterior wall was involved in 12 cases, while the anterior column was also involved in 4. Excellent or good reduction of the fracture was obtained in all of the cases. Immediately after surgery, a continuous passive motion apparatus for the hip was applied to be used for approximately 3 weeks. At final follow-up, which was obtained after a mean time of 5 years, all of the patients except 2 had obtained good results. Moderate joint deficit was present in 1 case, while sciatic nerve palsy that had already been observed prior to surgery persisted in another. Evident radiographic signs of coxarthrosis were not present in any of the cases. Based on the opinion of Salter et al. (1980), who in an experimental study had observed better healing of the cartilaginous lesions in the joints submitted to movement, immediately after surgery we applied a continuous passive motion apparatus for the hip in a group of patients affected with fracture of the acetabulum. As none of the patient followed-up by us presented evident signs of hip arthrosis, the authors hypothesize that continuous passive movement, immediately carried out after osteosynthesis, plays a significant role in preventing post-traumatic arthrosis of the hip. In truth, small irregularities of the acetabular cavity, possibly present after an apparently anatomical reduction, could be minimized by the plasmating effect of the head of the femur in movement.  相似文献   
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Characterization of neuronal death and neurogenesis in the adult brain of birds, humans, and other mammals raises the possibility that neuronal turnover represents a special form of neuroplasticity associated with stress responses, cognition, and the pathophysiology and treatment of psychiatric disorders. Multilayer neural network models capable of learning alphabetic character representations via incremental synaptic connection strength changes were used to assess additional learning and memory effects incurred by simulation of coordinated apoptotic and neurogenic events in the middle layer. Using a consistent incremental learning capability across all neurons and experimental conditions, increasing the number of middle layer neurons undergoing turnover increased network learning capacity for new information, and increased forgetting of old information. Simulations also showed that specific patterns of neural turnover based on individual neuronal connection characteristics, or the temporal-spatial pattern of neurons chosen for turnover during new learning impacts new learning performance. These simulations predict that apoptotic and neurogenic events could act together to produce specific learning and memory effects beyond those provided by ongoing mechanisms of connection plasticity in neuronal populations. Regulation of rates as well as patterns of neuronal turnover may serve an important function in tuning the informatic properties of plastic networks according to novel informational demands. Analogous regulation in the hippocampus may provide for adaptive cognitive and emotional responses to novel and stressful contexts, or operate suboptimally as a basis for psychiatric disorders. The implications of these elementary simulations for future biological and neural modeling research on apoptosis and neurogenesis are discussed.  相似文献   
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Stimulant-use disorders have been associated with lower availability of dopamine type-2 receptors (D2R) and greater availability of type-3 receptors (D3R). Links between D2R levels, cognitive performance, and suppression of the default mode network (DMN) during executive functioning have been observed in healthy and addicted populations; however, there is limited evidence regarding a potential role of elevated D3R in influencing cognitive control processes in groups with and without addictions. Sixteen individuals with cocaine-use disorder (CUD) and 16 healthy comparison (HC) participants completed [11C]-(+)-PHNO PET imaging of D2R and D3R availability and fMRI during a Stroop task of cognitive control. Independent component analysis was performed on fMRI data to assess DMN suppression during Stroop performance. In HC individuals, lower D2R-related binding in the dorsal putamen was associated with improved task performance and greater DMN suppression. By comparison, in individuals with CUD, greater D3R-related binding in the substantia nigra was associated with improved performance and greater DMN suppression. Exploratory moderated-mediation analyses indicated that DMN suppression was associated with Stroop performance indirectly through D2R in HC and D3R in CUD participants, and these indirect effects were different between groups. To our knowledge, this is the first evidence of a dissociative and potentially beneficial role of elevated D3R availability in executive functioning in cocaine-use disorder.Subject terms: Addiction, Cognitive control  相似文献   
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Pressure injuries burden patients and healthcare organisations, with some preventative practices having little impact on prevalence reduction. Patient participation in care may be an effective pressure injury prevention strategy, yet patient preferences are unknown. The aim of this interpretive study was to describe patients' perceptions of their current and future role in pressure injury prevention. Semi‐structured interviews were conducted with 20 adult inpatients recruited from four medical units, at two Australian metropolitan hospitals. Interview data were analysed using content analysis, with three categories emerging: ‘experiencing pressure injuries’; ‘participating in pressure injury prevention’; and ‘resourcing pressure injury prevention and treatment’. These categories reflect the complex nature of participants’ pressure injury experience. The findings suggest participants gather pressure injury knowledge from first‐hand and vicarious experience; knowledge they bring to hospital. Most participants preferred a proactive pressure injury prevention role. Many identified barriers in the healthcare environment that impeded their participation and affected their experience of pressure injuries and pressure injury prevention. If patient participation as a pressure injury prevention strategy is to be considered, nurses and organisations need to view patients as partners.  相似文献   
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