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21.
A comprehensive and reliable assessment of work stress, burnout, affective, and physical symptomatology was conducted with 260 hospital nurses. As previous attempts to categorize nursing stress and burnout by ward type have yielded inconsistent results, an alternative method for grouping nursing stress effects was sought. Cluster analysis was chosen as it offers a statistically sound means of delineating natural groupings within data. Sets of questionnaires measuring burnout, work stressors, and physical and emotional symptomatology were sent to all staff nurses at a large university hospital. Of 709 nurses employed there, a total of 260 nurses returned completed questionnaire packets. These nurses were separated into two equal groups using random sampling procedures. Cluster analysis of this data revealed groupings which were based on nursing stressors (particularly workload and conflict with physicians), social support, and patient loads. These cluster-analytic findings were replicated on both samples, and validated using data not used in the original cluster analysis. Results suggest that the effects of stress have more to do with the characteristics of the work environment and overall workload than with the degree of specialization on the unit. Results also suggest that intraprofessional conflict (i.e. with other nurses) is less psychologically damaging than is interprofessional conflict (i.e. conflict with physicians). Findings are discussed with respect to the burnout process and possible interventions. 相似文献
22.
化工行业职业性机械伤害危险因素的病例-交叉方法研究 总被引:6,自引:0,他引:6
目的 研究化工行业机械伤害的有关诱发因素,估计其作用强度。方法 采用病例-交叉设计的方法。以操作和检修时受伤的化工工人为研究对象,每个对象在受伤后2d内完成调查,收集他们受伤前10min、上一工作日同一段时间和受伤前1周内有关诱发因素暴露的信息,用配对时间段方法和一般频数法进行分析,评估各种诱发因素的危险度。结果 一般频数法分析的结构表明,操作方法异常、设备工具缺陷、工作紧迫、注意力不集中、不使用防护用品、精神状况较差、与同事配合不协调、工作环境发生变化等瞬时危害因素的RR值及95%可信限的下限均大于1。配对时间段方法分析的结果与其相拟,但95%可信限较宽。结论 化工行业职业性机械伤害的发生存在着诸多诱发因素。病例-交叉研究中的一般频数法与配对时间段方法相比,前者所得结果较为可靠,研究的相对效率较高。建议进一步使用多个时间段方法进行研究,以减小混杂因素的影响。 相似文献
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生长激素、肝细胞生长因子和烟酰胺对人胎胰岛细胞的增殖作用 总被引:2,自引:0,他引:2
目的研究生长激素(GH),肝细胞生长因子(HGF)和烟酰胺(NIC)对体外培养的人胎胰岛细胞的增殖作用及其交互作用。方法采用La(2^7)正交设计法在体外培养的人胎胰岛细胞的各组中分别加入不同浓度及组合的GH,HGF和NIC,培养48h后,收集各孔细胞,DTZ染色,计数。结果GH,HGF和NIC均起主要作用,HGF和NIC的交互作用不可忽视,最佳的生长因子组合及适配浓度为GH(100ng/ml)HGF(25ng/ml)NIC(100mmol/L)。结论GH,HGF和NIC均能促进体外培养的胰岛细胞的增殖,且组合GH(100ng/ml)HGF(25ng/ml)NIC(100mmol/L)的作用最大。 相似文献
25.
Data from a 1988 national drinking survey was cluster analysedto identify different types of male drinkers, to assist in thetargeting of health promotion strategies. Of the five segmentsgenerated by the clustering, one labelled Young Heavy DrinkingMales was identified as the most appropriate target segment,because although they were the segment reporting the highestlevel of alcohol-related problems they were also the segmentmost likely to feel they were drinking too much They were thereforethe segment most likely to be responsive to advertising thatsought to support people who wanted to change their drinkinghabits. They were also the most appropriate target for the longer-termgoal of changing the climate of opinion regarding the acceptabilityof more moderate drinking. Comparisons with two previous clusteranalyses showed a high degree of similarity, suggesting thatclustering is a reliable vehicle for identifying drinker types. 相似文献
26.
《Headache》1993,33(2):98-104
SYNOPSIS
Respiratory sinus arrhythmia is regarded as indicative of cardiac vagal integrity. A ratio of the longest R-R interval to the shortest R-R interval during deep breathing test (E:I ratio) was calculated in controls (n=49), cluster headache (n=33) and CPH (n=4) patients, E:I ratio decreased with age but was not dependent upon sex or upon smoking habits. Furthermore, there were no significant differences as regards E:I ratio between cluster headache patients in and outside a bout, or between patients with right-sided and left-sided headache. However, the E:I ratio was found to be significantly lower in the cluster headache group as such, when compared with controls, but the number of patients disclosing pathological or borderline results was small, 2 and 2, respectively. This may indicate that a putative vagal dysfunction in cluster headache is usually less marked than in patients with e.g. diabetic autonomic neuropathy. Significant attack-related change in the E:I ratio were detected in all individual patients though these changes were not of a uniform nature from individual to individual. E:I ratios were rather high in 3 out of 4 CPH patients examined. However, the number of patients in this group is too small to allow definite statements about the difference between CPH end cluster headache with regard to E:I ratios. There was no significant difference between E:I ratios outside and during a mild, short, mechanically precipitated attack in a single CPH patient. 相似文献
Respiratory sinus arrhythmia is regarded as indicative of cardiac vagal integrity. A ratio of the longest R-R interval to the shortest R-R interval during deep breathing test (E:I ratio) was calculated in controls (n=49), cluster headache (n=33) and CPH (n=4) patients, E:I ratio decreased with age but was not dependent upon sex or upon smoking habits. Furthermore, there were no significant differences as regards E:I ratio between cluster headache patients in and outside a bout, or between patients with right-sided and left-sided headache. However, the E:I ratio was found to be significantly lower in the cluster headache group as such, when compared with controls, but the number of patients disclosing pathological or borderline results was small, 2 and 2, respectively. This may indicate that a putative vagal dysfunction in cluster headache is usually less marked than in patients with e.g. diabetic autonomic neuropathy. Significant attack-related change in the E:I ratio were detected in all individual patients though these changes were not of a uniform nature from individual to individual. E:I ratios were rather high in 3 out of 4 CPH patients examined. However, the number of patients in this group is too small to allow definite statements about the difference between CPH end cluster headache with regard to E:I ratios. There was no significant difference between E:I ratios outside and during a mild, short, mechanically precipitated attack in a single CPH patient. 相似文献
27.
甲襞微循环观测辅助诊断的初步研究胡金麟*田牛*刘凤英*宋欣*李向红*规范化的甲襞、球结膜、舌、口唇、牙龈、耳廓、皮肤、子宫颈、阴茎头微循环观测方法标志着我国临床微循环的研究与应用已进入了一个新的阶段[1,2]。临床微循环观测结果的数学公式表达,促进了... 相似文献
28.
目的建立简单快速提取并测定N-亚硝基二正丙胺(NDPA)的方法。方法采用Trap3捕集管,利用标准吹扫捕集程序(吹扫气体流速40ml/min,吹扫时间11min,解吸温度225℃,解吸时间4min,烘烤温度230℃,烘烤时间10min),有效富集了化工废水中μg/L级的NDPA,建立了吹扫捕集(P&T)气相色谱质谱联用(GC-MS)化学源(CI)选择离子模式(uSIS)快速、准确分析废水中NDPA的分析方法。结果方法的相对标准偏差为7.5%;废水的加标回收率在62.60%~96.31%;在5~30μg/L范围内线性良好,线性回归系数为0.978;方法的最低检出限为3μg/L。结论采用P&T-GC-MS/CI/uSIS法可用于化工废水中半挥发性有机物NDPA的测定。 相似文献
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30.
Linda R White Lars Jacob Stovner Maurice B Vincent Ole Petter Løbben Yara D Fragoso Kristian S Bjerve Ottar Sjaastad 《Cephalalgia : an international journal of headache》1992,12(2):107-110
Our group has previously reported significant changes in the incorporation of precursors into glycerophospholipids, particularly phosphatidylserine, in polymorphonuclear cells obtained from the peripheral blood of cluster headache patients, when compared with controls. The potential of these results led to further work using both the previous methodology and a modified isolation technique to obtain polymorphonuclear cells in as pure a state as possible. Neither the new results obtained using the original technique, nor the results with high purity polymorphonuclear cells from controls and cluster headache patients, confirm the marked changes in precursor uptake into glycerophospholipids originally reported. 相似文献