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1.
Pathophysiology of SPINK mutations in pancreatic development and disease.   总被引:1,自引:0,他引:1  
The endogenous pancreatic trypsin inhibitor, SPINK, is believed to limit enzyme activity in the pancreas and reduce the risk of pancreatitis. Recently, mutations in the SPINK1 gene have been associated with development of both acute and chronic pancreatitis. In most patients with SPINK1 mutations, the genetic variants do not cause the disease independently, but may act in concert with other genetic or environmental factors. Recent studies, using mice in which the trypsin inhibitor gene has been deleted or overexpressed, provide novel insights into the role of SPINK in pancreatic development and pancreatitis.  相似文献   
2.
The skeletal effects from intensive exercise throughout puberty are undefined. Forty-five female gymnasts and 52 controls were studied over 3 years, including a heredity aspect. The effects of size, maturity, exercise, and diet were identified using a multilevel regression model. Results demonstrated sustained skeletal benefits resulting from exercise throughout all stages of pubertal development. INTRODUCTION: Weight-bearing exercise is beneficial for peak bone mass development. However, whether skeletal benefits achieved with exercise are maintained if training remains intensive throughout the pubertal years is not entirely clear. The influence of familial resemblance for bone mass remains undefined in physically active versus inactive children. The aim of this study was to investigate the long-term influences of impact-loading exercise on bone quantity and quality in young females after controlling for growth, maturation, and hereditary factors. MATERIALS AND METHODS: At baseline, 45 gymnasts (G) and 52 normally active controls (C) 8-17 years of age were recruited. Anthropometry, diet, physical activity, and quantitative ultrasound (QUS) were measured annually for 3 consecutive years. DXA scans of total body (TB) and lumbar spine (LS) bone mineral content (BMC) and density (BMD) were taken three times at 1-year intervals. A multilevel regression model was fitted, and the independent effects of body size, maturity, physical activity, and diet were identified over time. To assess heredity influences, 27 G mothers and 26 C mothers volunteered for cross-sectional measurements of anthropometry, QUS, and BMC/BMD. RESULTS AND CONCLUSIONS: Gymnasts were smaller and lighter (as were their mothers) than controls, but they had significantly higher QUS and axial and appendicular BMC and BMD, with > 170 g more bone mineral in TB across puberty (after adjustment for maturity [years from peak height velocity], height, weight, energy, and protein intake). Gymnasts had up to 24-51% higher BMC and 13-28% higher BMD, depending on skeletal site. These results provide evidence of sustained skeletal benefits from impact-loading exercise, which are unlikely to result entirely from heredity, throughout pubertal years.  相似文献   
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In order to study brain activity associated with “incidental” cognitive processing, regional cerebral blood flow (rCBF) was measured in six volunteers while they monitored a sequence of pseudo-words (e.g., FLOPE) for the rare occasions when the letters were displayed in blue rather than white. In the control condition, the same pseudo-word was presented repeatedly. In one experimental condition all 60 pseudo-words were different, while in the other there were 18 repetitions. Although it was not necessary to “read” the pseudo-words to perform the monitoring task, subsequent forced choice recognition memory for these stimuli was significantly greater than chance. Furthermore, there were significant differences in blood flow between the three conditions. When different pseudo-words were presented there was significantly greater activity in brain areas concerned with shape and object identity (extrastriate cortex bilaterally), with visual word form (left inferior temporal gyrus), and with articulatory word form (Broca's area) even though none of this information about the pseudo-words was needed for performance of the monitoring task. In the condition in which some of the words were repeated, there was significantly reduced activity in the right lingual gyrus. This area may therefore be a possible anatomical locus for repetition priming with verbal stimuli. These results indicate the importance of taking into account incidental processing when designing tasks for functional imaging experiments. © 1995 Wiley-Liss, Inc.  相似文献   
5.
Cholinesterase deficiency was detected in a young girl following an episode of post-anesthesia apnea. Subsequently, plasma and serum cholinesterase levels and dibucaine numbers were determined on blood samples from 56 members of her extended family. Including the proband, three individuals were identified with severe cholinesterase deficiency and 12 were found to have mild abnormalities. The occurrence of two genetic variants regulating cholinesterase production, the "silent" gene and the atypical enzyme, is postulated to account for the unusual pattern of inheritance in this family. Screening family members of confirmed cases is essential to prevent the potentially fatal consequences of this hereditary disorder.  相似文献   
6.
Event-related potential (ERP) studies have shown that the neural systems engaged during performance of oddball tasks are sensitive to contextual manipulations, such as the number of stimulus classes. Some ERP components (i.e., N1) are modulated by the number of stimulus types, while others (i.e., P3) are not greatly affected. However, little is known about how these contextual manipulations affect the hemodynamics underlying oddball processing. The purpose of this study was to examine the hemodynamic correlates of target stimulus processing in single-tone (targets alone) and two-tone (targets and standard tones) auditory oddball tasks. The primary hypothesis was that processing of salient stimuli in both contextual conditions would engage the same spatially distributed cortical and subcortical networks observed in previous oddball fMRI studies. Results were consistent with this hypothesis and suggest that the brain engages many potentially useful brain regions during salient stimulus processing despite the low probability that said regions are necessary for task performance, which likely reflects a form of “adaptive reflexive processing”. Results were also consistent with ERP data that shows that the N1 is larger for single-tone tasks by showing greater amplitude of hemodynamic response for single-tone targets, relative to two-tone targets, in bilateral temporal cortex and bilateral inferior lateral frontal cortex. The results are discussed as they relate to the understanding of neurocognitive function pertaining to contextual manipulations in general, and orienting processes in particular.  相似文献   
7.
Biopsies of 82 patients diagnosed as having Hodgkin's disease were reviewed. Seventeen were reclassified histologically as non-Hodgkin's lymphoma or reactive lymphoid hyperplasia. A substantial number of cases of Hodgkin's disease were negative when stained with Leu M1. Staining for Leu M1 was not found in the cases of non-Hodgkin's lymphoma or reactive lymphoid hyperplasia. With the exception of the lymphocyte predominant nodular subtype of Hodgkin's disease, epithelial membrane antigen staining was seen in a few cases of Hodgkin's disease and non-Hodgkin's lymphomas. This was not a useful discriminating feature.  相似文献   
8.
In this study, the authors examined the relation between adolescent and parent therapeutic alliances and treatment outcome among 65 substance-abusing adolescents receiving multidimensional family therapy. Observer ratings of parent alliance predicted premature termination from treatment. Observer ratings, but not self-report, of adolescent alliance predicted adolescents' substance abuse and dependency symptoms at posttreatment, as well as days of cannabis use at 3-month follow-up. The association between adolescent alliance and substance abuse and dependency symptoms at posttreatment was moderated by the strength of the parent alliance. Results reveal the unique and interactive effects of the 2 alliances on treatment outcome and emphasize the need for a systemic and well-articulated approach to developing and maintaining the multiple alliances inherent to family therapy.  相似文献   
9.
During the COVID-19 pandemic, breastfeeding women have experienced restricted access to support, placing them at increased risk of mental health concerns and limited breastfeeding assistance. This study investigated the effect of the pandemic on feeding choices and maternal wellbeing amongst breastfeeding mothers living in Australian and New Zealand. We conducted a cross-sectional online survey that examined feeding methods, maternal mental wellbeing, worries, challenges, and positive experiences during the pandemic. Most women were exclusively breastfeeding (82%). Partial breastfeeding was associated with perceived low milk supply and longer pregnancy duration during the pandemic. Reduced mental health and wellbeing was associated with lower levels of family functioning, increased perceived stress, and perinatal anxiety. Longer pregnancy duration during the pandemic was associated with lower mental health wellbeing scores, while higher perceived stress scores were reported for regions with higher COVID-19 infection rates and women with perceived low milk supply. Women reported that the pandemic resulted in less pressure and more time for family bonding, while worries about the pandemic, family health, and parenting challenges were also cited. Mental health concerns of breastfeeding women appear to be exacerbated by COVID-19, highlighting a critical need for access to mental health and broader family support during the pandemic.  相似文献   
10.
Journal of Immigrant and Minority Health - This study explored the epidemiology and health literacy of people affected by viral hepatitis (VH) from migrant culturally and linguistically diverse...  相似文献   
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