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41.
文章分析了SOMATOM PLUS 4的NVRAM故障原因,并介绍了该故障的排除方法.  相似文献   
42.
The optometric profession in the UK has a major role in the detection, assessment and management of ocular anomalies in children between 5 and 16 years of age. The role complements a variety of associated screening services provided across several health care sectors. The review examines the evidence-base for the content, provision and efficacy of these screening services in terms of the prevalence of anomalies such as refractive error, amblyopia, binocular vision and colour vision and considers the consequences of their curtailment. Vision screening must focus on pre-school children if the aim of the screening is to detect and treat conditions that may lead to amblyopia, whereas if the aim is to detect and correct significant refractive errors (not likely to lead to amblyopia) then it would be expedient for the optometric profession to act as the major provider of refractive (and colour vision) screening at 5-6 years of age. Myopia is the refractive error most likely to develop during primary school presenting typically between 8 and 12 years of age, thus screening at entry to secondary school is warranted. Given the inevitable restriction on resources for health care, establishing screening at 5 and 11 years of age, with exclusion of any subsequent screening, is the preferred option.  相似文献   
43.
观察凹透镜和凸透镜对豚鼠眼球生长和屈光变化的影响,建立透镜诱导型屈光不正动物模型。方法:3~4周龄有色豚鼠47只,随机分成7组,右眼分别戴不同度数的凸或凹透镜,其左眼作为对照眼,戴镜前和戴镜后第11天分别测量其眼轴长度、屈光度,观察其变化。结果:戴镜后第11天与戴镜前相比,戴+4.00?D、+8.00?D组的豚鼠眼分别增加了+1.46?D与+1.58?D的相对远视(P<0.05);戴-4.00?D、-8.00?D、-15.00?D组的豚鼠分别增加了-2.92?D、-3.17?D、-3.10?D的相对近视(P<0.01);而戴0.00?D、-2.00?D组的豚鼠的屈光度差异无统计学意义(P>0.05)。7组豚鼠的眼轴长度在实验眼和对照眼之间差异无统计学意义(P>0.05)。结论:豚鼠眼球生长发育受透镜影响,可被用来建立一种简单经济的屈光不正动物模型。  相似文献   
44.
Aim: To describe how reliability assessment data in the WHO Multicentre Growth Reference Study (MGRS) were collected and analysed, and to present the results thereof.
Methods: There were two sources of anthropometric data (length, head and arm circumferences, triceps and subscapular skinfolds, and height) for these analyses. Data for constructing the WHO Child Growth Standards, collected in duplicate by observer pairs, were used to calculate inter-observer technical error of measurement (TEM) and the coefficient of reliability. The second source was the anthropometry standardization sessions conducted throughout the data collection period with the aim of identifying and correcting measurement problems. An anthropometry expert visited each site annually to participate in standardization sessions and provide remedial training as required. Inter- and intra-observer TEM, and average bias relative to the expert, were calculated for the standardization data.
Results: TEM estimates for teams compared well with the anthropometry expert. Overall, average bias was within acceptable limits of deviation from the expert, with head circumference having both lowest bias and lowest TEM. Teams tended to underestimate length, height and arm circumference, and to overestimate skinfold measurements. This was likely due to difficulties associated with keeping children fully stretched out and still for length/height measurements and in manipulating soft tissues for the other measurements. Intra- and inter-observer TEMs were comparable, and newborns, infants and older children were measured with equal reliability. The coefficient of reliability was above 95% for all measurements except skinfolds whose R coefficient was 75–93%.
Conclusion: Reliability of the MGRS teams compared well with the study's anthropometry expert and published reliability statistics.  相似文献   
45.
【目的】观察配戴角膜塑形镜1年并停戴1月后的屈光状态和角膜前表面参数的恢复情况,并分析屈光度变化的相关因素。【方法】回顾性病例研究。收集66例(66眼)配戴角膜塑形镜并自愿停戴的8~15岁近视儿童,配戴时间约1年,平均13(S=3)月,停戴平均29(S=4)d。观察戴镜前及停戴1月的屈光度、眼轴、眼压、前房深度及角膜地形图参数,采用配对t检验和Pearson相关性分析停戴后的各参数变化及其相关性。【结果】与配戴角膜塑形镜前相比,停戴1月后的等效球镜度增长了-0.13(-0.50~0.00)D(P<0.001),其中柱镜度数增长了0.00(-0.25~0.00)D,(P=0.013)。停戴1月的角膜陡峭K值、平坦K值、平坦和陡峭偏心率较戴镜前分别减少了0.10(-0.10~0.30)D、0.20(0.00~0.48)D、-0.10(-0.30~0.20)D,(P1=0.001、P2<0.001、P3=0.015)。戴角膜塑形镜1年并停戴1月后屈光度增长量(Y)仅与眼轴增长值(X)具有密切联系,并建立回归方程^y=-1.294X+0.095(P<0.001)。【结论】儿童停戴角膜塑形镜1月后的屈光状态已经超过戴镜前水平,角膜前表面形态基本恢复到戴镜前的初始形态。  相似文献   
46.
47.
Neurotherapeutic potentials of Centella asiatica and its reputation to boost memory, prevent cognitive deficits and improve brain functions are widely acknowledged. The plant's bioactive compounds, i.e. asiaticoside, madecassoside and asiatic acid were reported to have central nervous system (CNS) actions, particularly in protecting the brain against neurodegenerative disorders. Hence, it is important for these compounds to cross the blood-brain barrier (BBB) to be clinically effective therapeutics. This study aimed to explore the capability of asiaticoside, madecassoside and asiatic acid to cross the BBB using in vitro BBB model from primary porcine brain endothelial cells (PBECs). Our findings showed that asiaticoside, madecassoside and asiatic acid are highly BBB permeable with apparent permeability (Papp) of 70.61 ± 6.60, 53.31 ± 12.55 and 50.94 ± 10.91 × 10?6 cm/s respectively. No evidence of cytotoxicity and tight junction disruption of the PBECs were observed in the presence of these compounds. Asiatic acid showed cytoprotective effect towards the PBECs against oxidative stress. This study reported for the first time that Centella asiatica compounds demonstrated high capability to cross the BBB, comparable to central nervous system drugs, and therefore warrant further development as therapeutics for the treatment of neurodegenerative diseases.  相似文献   
48.
SUMMARY

Effective post-hospital home medication management among older adults is a convoluted, error-prone process. Older adults, whose complex medication regimens are often changed at hospital discharge, are susceptible to medication-related problems (e.g., Adverse Drug Events or ADEs) as they resume responsibility for managing their medications at home. Human error theory frames the discussion of multi-faceted, interacting factors including care system functions, like discharge medication teaching that contribute to post-hospital ADEs. The taxonomy and causes of post-hospital ADEs and related risk factors are reviewed, as we describe in high-risk older adults a population that may benefit from targeted interventions. Potential solutions and future research possibilities highlight the importance of interdisciplinary teams, involvement of clinical pharmacists, use of transitional care models, and improved use of informational technologies.  相似文献   
49.
BackgroundPrescribing errors are prevalent in hospital settings with provision of feedback recommended to support prescribing of doctors. Feedback on prescribing has been described as feasible and valued but limited by doctors, with pharmacists described as credible facilitators of prescribing feedback. Evidence supporting prescribing feedback has been limited to date. A formalised programme of pharmacist-led prescribing error feedback was designed and implemented to support prescribers.ObjectiveTo evaluate the impact of a prescribing feedback intervention on prescribing error rates and frequency of prescribing error severity and type.MethodProspective prescribing audits were undertaken across sixteen hospital wards in a UK teaching hospital over a five day period with 36 prescribers in the intervention group and 41 in the control group. The intervention group received pharmacist-led, individualised constructive feedback on their prescribing, whilst the control group continued with existing practice. Prescribing was re-audited after three months. Prescribing errors were classified by type and severity and data were analysed using relevant statistical tests.ResultsA total of 5191 prescribed medications were audited at baseline and 5122 post-intervention. There was a mean prescribing error rate of 25.0% (SD 16.8, 95% CI 19.3 to 30.7) at baseline and 6.7% (SD 9.0, 95% CI 3.7 to 9.8) post-intervention for the intervention group, and 19.7% (SD 14.5, 95% CI 15.2 to 24.3) at baseline and 25.1% (SD 17.0, 95% CI 19.8 to 30.6) post-intervention for the control group with a significant overall change in prescribing error rates between groups of 23.7% (SD 3.5, 95% CI, ?30.6 to ?16.8), t(75) = ?6.9, p < 0.05. The frequency of each error type and severity rating was reduced in the intervention group, whilst the error frequency of some error types and severity increased in the control group.ConclusionPharmacist-led prescribing feedback has the potential to reduce prescribing errors and improve prescribing outcomes and patient safety.  相似文献   
50.
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