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71.
Summary The rate of unstimulated influx of Ca2+ into rat aorta smooth muscle, measured as uptake of 45Ca, was inhibited in the presence of endothelium as compared to influx in the absence of endothelium. Efflux of 45Ca from unstimulated prelabelled tissues was also reduced in the presence of endothelium. In normal physiological solution the rate of influx and efflux of Ca2+ stimulated by B-HT 920 (1 and 10 M), but not that stimulated by phenylephrine (30 nM and 1 M), was also reduced in the presence of endothelium. In the presence of the calcium entry blocker flunarizine (3 M), phenylephrine (1 M) stimulated efflux of Ca2+ was inhibited by the presence of endothelium. A correlation between inhibition of Ca2+ influx and modulation of -adrenoceptor agonist-induced contractions by endothelium could not be demonstrated, and methylene blue, an antagonist of endothelium mediated inhibition of B-HT 920 contractions, did not affect Ca2+ influx stimulated by the agonist. The effects of endothelium on Ca2+ influx and efflux are unlikely to be due to alterations by endothelium of diffusion of 45Ca or the agonists in the vessel. The results demonstrate that an endothelial derived factor or factors can reduce calcium influx into smooth muscle cells and also modulate the release of calcium from cells, perhaps by affecting intracellular calcium pumping mechanisms. A reduction of calcium influx cannot be the sole explanation for the modulatory effect of endothelium on -adrenoceptor agonist-induced contractions but an effect on intracellular calcium metabolism may be important.  相似文献   
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Idiopathic pulmonary fibrosis is a progressive fibrotic lung disease that is on the rise globally. The disease is associated with significant morbidity and hence poses significant challenges for their informal carers, particularly daughters in mid-adulthood, who struggle with their own personal demands and that of their ill parents. Yet there is a dearth of literature on the experiences of these specific carers. Hence, the purpose of this study is to explore the lived experiences of daughters caring for a parent with pulmonary fibrosis within a community setting. This was explored using a phenomenological qualitative framework that was conducted between January and April 2017. Semi-structured audio-recorded interviews were conducted with six adult daughters who provided care to a parent having pulmonary fibrosis. Purposive sampling was used to recruit study participants. Transcribed data were analysed using Interpretative Phenomenological Analysis. Three main themes were extracted which communicate the essence of the daughters’ lived experiences: “Walking on tiptoes”, “Flooded by emotions” and “Shifts in family dynamics.” Participants described experiencing the toll of being constantly vigilant for symptoms. They also expressed a range of emotions that included guilt, helplessness and worry related to their care experience. However, these emotional struggles were suppressed in order to present an external facade of strength and control. A shift in roles was also described where the daughters became the informal carers/support for both their ill and well parent, albeit in different ways. Caring for a person with pulmonary fibrosis is an emotional and life changing experience and hence, there is the need for individualised interventions that target the unique perceptions of these informal carers.  相似文献   
73.
Background: Low energy availability results in physiological adaptations which contribute to unfavourable health outcomes. Little information exists on perceptions of nutritional advice to eat more food to maintain health and enhance performance. The aim of this study was to explore athletes’ and coaches’ perceptions towards advice to athletes to eat larger than their current quantities of food and to explore how nutritionists could deliver this advice. Methods: Semi-structured interviews (~20 min in length) were conducted using online communication technology, audio-recorded, and transcribed verbatim. The interview explored perceptions of the nutritional advice provided, its role in health and performance, and the challenges to eating larger amounts of food. Data were analysed using NVIVO 1.2 using an inductive thematic approach. Results: Nine elite athletes (female = 6; males = 3) and nine high-performance coaches (female = 3; male = 6) completed the semi-structured interviews. Athletes reported improved training consistency, fewer injuries and illnesses, and improved resilience when consuming adequate energy and nutrients to meet their needs. Lack of time and meal preparation difficulties were the main challenges faced to fuelling. Conclusions: Although education about under-fuelling is important, motivating, enabling, and supporting athletes to change behaviour is pivotal to increasing athlete self-awareness and to make long-term nutritional changes.  相似文献   
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IntroductionDetermining the efficacy of anti-scar technologies can be difficult as qualitative, subjective assessments are often utilized instead of systematic, objective measures. Perceptions regarding the reliability of instruments for quantitative measurements along with their high cost and increased data collection time may discourage their use, leading to use of scar scales which are relatively quick and low-cost. To directly evaluate the reliability of instruments for quantitative measurements of scar properties, instruments and two qualitative scales were compared by assessing a variety of cutaneous scars.MethodsScar height and surface texture were evaluated using a 3D scanner and a mold/cast technique. Scar color was evaluated by using a spectroscopy-based tool, the Mexameter®, and digital photography with image analysis. Scar biomechanics were evaluated using the BTC-2000?, Dermal Torque Meter (DTM®), and ballistometer®. The Vancouver Scar Scale (VSS) and Patient and Observer Scar Assessment Scale (POSAS) were used to qualitatively evaluate the same scar properties. Intraclass correlation coefficients (ICC) were used to determine inter- and intra-user reliability (poor, moderate, good, excellent) with all instruments and the kappa reliability statistic was used to asses inter-user reliability (poor, fair, moderate, good, very good) for VSS and POSAS. Time for measurement collection and after collection analysis was also recorded.ResultsThe Mexameter® was the most reliable method for evaluating erythema and pigmentation compared to digital photography and image processing, POSAS and VSS. Digital photography and analysis was more reliable than POSAS and VSS. Assessment of scar height was significantly more reliable when using a 3D scanner versus VSS and POSAS. The 3D scanner and mold-cast techniques also offered an additional benefit of providing an absolute value of scar height relative to the surrounding tissue. Intra-user reliability for all mechanical tests was moderate to good. Inter-user reliability was greater when using the BTC-2000? and ballistometer® versus the DTM®. All quantitative measurements took less than 90 s for collection, with the exception of the mold/cast technique.ConclusionNon-invasive instruments allow scar properties to be quantitatively assessed with high sensitivity and as a function of time and/or treatment without the need for biopsy collection. Overall, the reliability of scar assessments was significantly improved when quantitative instruments were utilized versus scar scales. Quantitative assessment of color and biomechanics were swift, requiring less than 90 s per measurement while assessments of texture and height required additional analysis time after collection. With proper training of clinical staff and well-defined protocols for measurement collection, reliable, quantitative assessments of scar properties can be collected with little disruption to the clinical workflow.  相似文献   
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According to a growing body of research, betrayal by a romantic partner is increasingly considered as a form of interpersonal trauma. Between 30% and 60% of betrayed individuals experience symptoms of post-traumatic stress disorder (PTSD), depression and anxiety to clinically meaningful levels. From a clinical perspective, this constellation of symptoms can be conceptualized as a stressor-related adjustment disorder. Yet, no qualitative research has examined the association between romantic betrayal and traumatic stress from the perspective of betrayed individuals. Face-to-face semi-structured interviews were conducted with 13 participants who had completed a clinical trial for a new treatment for adjustment disorder stemming from betrayal. Data were analysed using thematic content analysis. Although betrayal was experienced as a shocking and destabilizing event, and participants used trauma or ‘feeling traumatized’ as a metaphor to describe their experience, few had constructed their reaction as traumatic stress. In fact, participants reported experiencing difficulties understanding the intensity of their experience. However, when exposed to external sources (e.g., books and interviews by psychologists and researchers) that used a trauma and PTSD framework to explain the effects of betrayal, participants reported feeling clarity, validation and relief. Findings are discussed in the light of theoretical and clinical implications.  相似文献   
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Two types of sex education are generally offered in the U.S. abstinence-only and comprehensive sex education. There is no clear scientific consensus over which approach minimizes the risk of unintended pregnancy and sexually transmitted diseases for youth. While there have been many studies of specific programs in clinical or quasi-experimental settings, there are very few evaluations of how state-level sex education policies affect the youth population. We estimate the impact of various state-level sex education policies on youth sexual activity and contraceptive use using data from four waves of the Youth Risk Behavior Surveillance System from 39 states. We found that states that require sexuality (sex and/or HIV/STD) education and contraceptive content or states that mandate education but leave the actual content up to local districts have lower rates of sexually active youth and higher rates of contraception use when youth are sexually active. States that require sexuality education and require abstinence content increase the rate at which youth are sexually active, and youth in those states are less likely to use hormonal birth control if they are sexually active. In conclusion, we found that state policies regarding sex and HIV/STD education had statistically significant effects that are meaningful in magnitude from a public health perspective.

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80.
ObjectiveTo develop novel, scalable, and valid literacy profiles for identifying limited health literacy patients by harnessing natural language processing.Data SourceWith respect to the linguistic content, we analyzed 283 216 secure messages sent by 6941 diabetes patients to physicians within an integrated system''s electronic portal. Sociodemographic, clinical, and utilization data were obtained via questionnaire and electronic health records.Study DesignRetrospective study used natural language processing and machine learning to generate five unique “Literacy Profiles” by employing various sets of linguistic indices: Flesch‐Kincaid (LP_FK); basic indices of writing complexity, including lexical diversity (LP_LD) and writing quality (LP_WQ); and advanced indices related to syntactic complexity, lexical sophistication, and diversity, modeled from self‐reported (LP_SR), and expert‐rated (LP_Exp) health literacy. We first determined the performance of each literacy profile relative to self‐reported and expert‐rated health literacy to discriminate between high and low health literacy and then assessed Literacy Profiles’ relationships with known correlates of health literacy, such as patient sociodemographics and a range of health‐related outcomes, including ratings of physician communication, medication adherence, diabetes control, comorbidities, and utilization.Principal FindingsLP_SR and LP_Exp performed best in discriminating between high and low self‐reported (C‐statistics: 0.86 and 0.58, respectively) and expert‐rated health literacy (C‐statistics: 0.71 and 0.87, respectively) and were significantly associated with educational attainment, race/ethnicity, Consumer Assessment of Provider and Systems (CAHPS) scores, adherence, glycemia, comorbidities, and emergency department visits.ConclusionsSince health literacy is a potentially remediable explanatory factor in health care disparities, the development of automated health literacy indicators represents a significant accomplishment with broad clinical and population health applications. Health systems could apply literacy profiles to efficiently determine whether quality of care and outcomes vary by patient health literacy; identify at‐risk populations for targeting tailored health communications and self‐management support interventions; and inform clinicians to promote improvements in individual‐level care.  相似文献   
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