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81.
Persistent hyperinsulinemic hypoglycaemia of infancy (PHHI) is the most frequent cause of hypoglycaemia in infancy. Clinical presentation is heterogeneous, with variable onset of hypoglycaemia and response to diazoxide, and presence of sporadic or familial forms. Underlying histopathological lesions can be focal or diffuse. Focal lesions are characterised by focal hyperplasia of pancreatic islet-like cells, whereas diffuse lesions implicate the whole pancreas. The distinction between the two forms is important because surgical treatment and genetic counselling are radically different. Focal lesions correspond to somatic defects which are totally cured by limited pancreatic resection, whereas diffuse lesions require a subtotal pancreatectomy exposing to high risk of diabetes mellitus. Diffuse lesions are due to functional abnormalities involving several genes and different transmission forms. Recessively inherited PHHI have been attributed to homozygote mutations for the beta-cell sulfonylurea receptor (SUR1) or the inward-rectifying potassium-channel (Kir6.2) genes. Dominantly inherited PHHI can implicate the glucokinase gene, particularly when PHHI is associated with diabetes, the glutamate dehydrogenase gene when hyperammonaemia is associated, or another locus.  相似文献   
82.
Type 1 diabetes: pathogenesis and prevention   总被引:5,自引:0,他引:5       下载免费PDF全文
Type 1 diabetes results from the autoimmune destruction of insulin-producing β cells in the pancreas. Genetic and, as yet undefined, environmental factors act together to precipitate the disease. The excess mortality associated with the complications of type 1 diabetes and the increasing incidence of childhood type 1 diabetes emphasize the importance of therapeutic strategies to prevent this chronic disorder. Why is it considered that type 1 diabetes might be preventable? Different strands of diabetes research are coming together to suggest therapeutic targets. Islet cell autoantibody assays make it possible to accurately identify people at risk of future disease. In most cases, a long prodrome provides a window of opportunity to reverse the autoimmune process. Although no current “cure” exists, recent genetic data and preliminary trial results suggest T cells as a target for preventive strategies. Another potentially attainable target is induction of tolerance to the β-cell proteins such as insulin that are inappropriately recognized. Other strategies involve β-cell replacement, but currently there are insufficient donor cells available. This may be overcome as the processes controlling the differentiation of pancreatic and nonpancreatic progenitors as well as replication of existing islet β cells are unravelled.  相似文献   
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84.
The aims were to determine the median survival and prognostic factors of patients with central nervous system (CNS) metastases managed with whole‐brain radiation therapy (WBRT), and to explore selection criteria in recently published clinical trials using aggressive interventions in CNS metastases. A retrospective audit was performed on patients managed with WBRT for CNS metastases. Potential prognostic factors were recorded and analysed for their association with survival duration. The proportion of patients with these factors was also compared with those of patients managed under three recently reported studies investigating aggressive interventions, such as radiosurgery and chemotherapy for CNS metastases. Seventy‐three patients were treated with WBRT for cerebral metastases over a 12‐month period. The median survival of the population was 3.4 months (95% confidence interval: 2.7–4.1), with 6‐ and 12‐month survival rates of 30 and 18%, respectively. Significant prognostic factors for prolonged median survival were Eastern Cooperative Oncology Group status 0–2 (P = 0.015), Medical Research Council neurological functional status 0–1 (P = 0.006), and Recursive Partitioning Analysis Class 2 versus Class 3 (P = 0.020). On multivariate analysis, younger patient age (P = 0.02) and better performance status (P < 0.01) were associated with improved outcome. When comparing these characteristics with selected published studies, our study cohort demonstrated a higher proportion of patients with poor performance status, a greater number of metastases per patient and a higher incidence of extracranial disease. This reflects the selected nature of patients in these published studies. Central nervous system metastases confer a poor prognosis and, for the majority of patients, aggressive interventions are unlikely to improve survival. The use of potentially toxic and expensive treatments should be reserved for those few in whom these studies have shown a potential benefit.  相似文献   
85.
There are limited epidemiological data dedicated to geriatric acetabular fractures. The incidence in individuals older than 60 years of age has more than doubled in the past three decades and expected to double further over the next 20 years. These fractures represent a challenging subset of acetabular trauma patients to treat. Conservative treatment is a valid option in those with minimal displaced fractures and a preserved congruent hip joint. Similarly the frail patient with multiple medical co-morbidities and those unlikely to tolerate surgical intervention should have appropriate analgesia and their fracture managed or ignored by watchful neglect. Surgical treatment options include percutaneous fixation or open reduction and internal fixation techniques. Good outcomes may be expected should a concentric reduction be achieved. Age-related involutional osteoporosis associated with fracture comminution and acetabular dome impaction complicate surgical fixation with higher complication rates and the need for further surgery recognised. Historically described as central fracture dislocations, stoved in hip or burst fracture, acute arthroplasty is advocated in the setting of femoral head damage and in significant acetabular impaction injuries. Controversy remains whether geriatric patients should be treated by open reduction and internal fixation or total hip arthroplasty either acute or delayed and needs to be assessed based on the patient and personality of the fracture.  相似文献   
86.
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   
87.
This article presents an overview of the relationship between the osteopathic cranial concept and its dental considerations. The philosophy states that the brain and spinal cord, the cerebrospinal fluid, the cranial dural membranes, the cranial bones, and the sacrum move in a slight but perceptible physiologic cycle. The temporomandibular joint structures are an integral part of the craniosacral mechanism.

Because of the direct relationship in health between physical structure and function, this craniosacral rhythm is critical to the well-being of the patient. The oral tissues must allow for complete freedom of motion in the craniosacral cycle. A restriction or distortion of this movement may contribute significantly to the patient's temporomandibular joint condition. It is rational to assume that dental appliance therapy, orthodontic tooth movement, occlusal equilibration, tooth extraction, and other common dental procedures should be predicated on the optimum function of this mechanism.  相似文献   
88.
Emerging zoonotic infectious diseases pose a serious threat to global health. This is especially true in relation to the great apes, whose close phylogenetic relationship with humans results in a high potential for microorganism exchange. In this review, we show how studies of the microorganisms of wild great apes can lead to the discovery of novel pathogens of importance for humans. We also illustrate how these primates, living in their natural habitats, can serve as sentinels for outbreaks of human disease in regions with a high likelihood of disease emergence. Greater sampling efforts and improvements in sample preservation and diagnostic capacity are rapidly improving our understanding of the diversity and distribution of microorganisms in wild great apes. Linking non-invasive diagnostic data with observational health data from great apes habituated to human presence is a promising approach for the discovery of pathogens of high relevance for humans.  相似文献   
89.
Workplace violence committed by patients and visitors has high propensity to occur against emergency department employees. This article reports the association of worker, workplace, and community/environmental factors with violence risks. A cross-sectional research design was used with 280 employees from six emergency departments in the Midwest United States. Respondents completed the Survey of Violence Experienced by Staff and a 10-item demographic questionnaire. Data were analyzed using frequencies, percentages, Chi-square tests, and adjusted relative risks with 95% confidence intervals. Over 80% of respondents experienced at least one type of workplace violence with their current employer and approximately 40% experienced all three types. Risks for workplace violence were significantly higher for registered nurses and hospital-based emergency departments. Workplace violence can impact all employees in the emergency department regardless of worker, workplace, and community/environmental factors.  相似文献   
90.
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