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61.
目的 探讨丁苯酞对老年患者腹腔镜胆囊术后认知功能障碍和S100β的影响.方法 选取该院2012年12月至2014年12月行腹腔镜胆囊术的老年患者162例,采用随机数字表法分为两组,81例患者术前静脉输注75 mg丁苯酞氯化钠注射液为观察组,81例患者术前静脉输注等量生理盐水为对照组.比较两组患者脑氧代谢情况、认知功能状况、S100β.结果 术后,对照组颈静脉血氧饱和度(SjvO2)、桡动脉-颈内静脉球部血氧含量差(Da-jvO2)、脑氧摄取率(CEO2)、桡动脉-颈内静脉球部乳酸差(VADL)、S100β平稳波动;T0~T1时简易精神状态量表(MMSE)评分、蒙特利尔认知评估量表(MoCA)评分显著降低,而后逐渐升高,T3时恢复至术前;T0~T1时美国国立卫生院神经功能缺损(NIHSS)评分、认知功能障碍发生率显著增加,而后逐渐降低,T3时恢复至术前.观察组VADL平稳波动;T0~T1时SjvO2、NIHSS评分、认知功能障碍发生率显著增加,而后逐渐降低,T3时恢复至术前;T0~T1时Da-jvO2、CEO2、MMSE评分、MoCA评分、S100β显著降低,而后逐渐升高,T3时恢复至术前;观察组SjvO2、MMSE评分、MoCA评分T1、T2时均明显高于对照组.观察组Da-jvO2、CEO2、NIHSS评分、认知功能障碍发生率、S100β T1、T2时均明显低于对照组,差异均有统计学意义(P<0.05).结论 丁苯酞可明显改善老年患者腹腔镜胆囊术后认知功能状况,降低S100β,与脑氧代谢有关.  相似文献   
62.
背景 术后认知功能障碍(postoperative cognitive dysfunction,POCD)是一种常见的围术期并发症.γ-氨基丁酸A型(γ-aminobutyricacid type A,GABAA)受体作为一种中枢神经抑制性受体,可能对POCD的发生起着关键性作用.目的 综述以GABAA受体为靶点的相关药物对POCD的影响.内容 与GABAA受体相关的3类药物:激动剂、拮抗剂和反向激动剂,对POCD可分别产生诱发、逆转和改善症状的作用. 趋向 对记忆或者认知功能损害具有改善作用的GABAA受体相关药物,对POCD的治疗具有重大意义,将成为今后POCD的研究热点.  相似文献   
63.
Public health professionals work with a variety of information sources to carry out their everyday activities. In recent years, interactive computational tools have become deeply embedded in such activities. Unlike the early days of computational tool use, the potential of tools nowadays is not limited to simply providing access to information; rather, they can act as powerful mediators of human-information discourse, enabling rich interaction with public health information. If public health informatics tools are designed and used properly, they can facilitate, enhance, and support the performance of complex cognitive activities that are essential to public health informatics, such as problem solving, forecasting, sense-making, and planning. However, the effective design and evaluation of public health informatics tools requires an understanding of the cognitive and perceptual issues pertaining to how humans work and think with information to perform such activities. This paper draws on research that has examined some of the relevant issues, including interaction design, complex cognition, and visual representations, to offer some human-centered design and evaluation considerations for public health informatics tools.  相似文献   
64.
65.

The objective of this study was to determine behavioral, personal, and environmental factors that influence low‐income children's fruit and vegetable intake. Focus group questions were developed using the social cognitive theory (SCT). Four Caucasian (27 children) and six Mexican American focus groups (30 children) were conducted. Mexican‐American children stated they had the ability to prepare vegetables and fruits whereas Caucasian children expressed they would rather have their parents do the preparation. This is an example of the behavioral capability construct of SCT. Both ethnic groups mentioned they did not know where vegetables and fruits were stored in the home and this is an environmental construct of SCT. Personal factors of the SCT included Caucasian children preferring to add peanut butter and Ranch dip to vegetables compared to Mexican‐American children preferring to add salt, lime, and chili to vegetables. Sweetness, sourness, juiciness, and crunchiness were seen as good characteristics. All focus groups perceived vegetables and fruits as healthy. All of these issues need to be considered when developing nutrition programming for children.  相似文献   
66.
Abstract

Objective: The aim of this study was to describe how persons in the early stages of Alzheimer's disease (AD) became users of assistive technology (AT), and what the use of AT came to mean to these users and, when relevant, their significant others. Methods: Persons with AD were provided with individually chosen AT during a six-month period. Semi-structured interviews were conducted during the intervention period. The data were analysed with a constant comparative approach. Results: On the way towards becoming a user of AT, four junctures were identified, at which significant decisions were made by the participants. These decisions influenced whether to become a user or not and related to how the initial decision was made, how the routines to incorporate the AT were adjusted, whether the participant trusted the AT, and whether the participants felt an increased sense of capacity when using the AT. As users, the participants perceived how time and effort was saved, how worries and stress decreased, and how their sense of safety increased, which enabled them to perform valued activities, e.g. health-promoting and social activities, to a greater extent and in a more relaxed way than before. Conclusions: The findings support the view that AT can positively affect the activity performance of people with AD when the potential user can identify difficulties and needs and is motivated and able to make changes to overcome them, given that appropriate human support is available.  相似文献   
67.
Abstract

1.?Folate, an essential micronutrient, is a critical cofactor in one-carbon metabolism. Mammals cannot synthesize folate and depend on supplementation to maintain normal levels. Low folate status may be caused by low dietary intake, poor absorption of ingested folate and alteration of folate metabolism due to genetic defects or drug interactions.

2.?Folate deficiency has been linked with an increased risk of neural tube defects, cardiovascular disease, cancer and cognitive dysfunction. Most countries have established recommended intakes of folate through folic acid supplements or fortified foods. External supplementation of folate may occur as folic acid, folinic acid or 5-methyltetrahydrofolate (5-MTHF).

3.?Naturally occurring 5-MTHF has important advantages over synthetic folic acid – it is well absorbed even when gastrointestinal pH is altered and its bioavailability is not affected by metabolic defects. Using 5-MTHF instead of folic acid reduces the potential for masking haematological symptoms of vitamin B12 deficiency, reduces interactions with drugs that inhibit dihydrofolate reductase and overcomes metabolic defects caused by methylenetetrahydrofolate reductase polymorphism. Use of 5-MTHF also prevents the potential negative effects of unconverted folic acid in the peripheral circulation.

4.?We review the evidence for the use of 5-MTHF in preventing folate deficiency.  相似文献   
68.
69.
This paper presents evidence that first year students in the professions allied to medicine come to their course of study with well formed and fiercely defended models of therapeutic practice. These models are essentially traditional, skill based and contingent upon an ethic of cure and they reflect the “technical rationality” of which Schön (1992) speaks. It is argued that such models, which form the students' cognitive schemas, act as a filter or block through which the students accept or reject topics and concepts offered to them. In particular notions of reflective practice, negotiation and partnership and their predicates, psychology, medical sociology and methods of enquiry, may simply be too sophisticated for the student at this stage. It is further argued that reflection does not come naturally and must be introduced at an appropriate time, and carefully instilled and supported in training during initial clinical exposure.  相似文献   
70.
The purpose of this study is to review and analyze the literature on retirement from an occupational perspective. Theories are compared and described; whether they have empirical support and whether they incorporate individual and environmental factors is discussed. The Model of Human Occupation is presented as one such model that is able to incorporate both individual and environmental factors when retirement issues are added to the model.  相似文献   
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