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41.
目的 开发全科住培医师职业内驱力测量量表,并检验其信效度。方法 结合职业内驱力和全科住培医师发展现状的文献分析和质性访谈结果,构建量表条目池。通过专家德尔菲咨询,形成初版量表。对403名全科住培医师进行问卷调查,检验量表的信效度。结果 全科住培医师职业内驱力量表包括11个条目,划分为3个维度;量表的Cronbach’s α系数为0.945;各个维度的Cronbach’s α系数均在0.850以上,KMO系数为0.925。因子分析显示,所有条目的因子载荷均≥0.4,共同性均>0.2,保留11个条目。经因子分析抽取3个公因子进行相关分析提示:量表总分的各公因子之间相关系数大于0,且呈现出显著正相关(P<0.01)。根据各因子所含条目内容、理论研究和专家建议,分别将其命名为学科归属、发展期望、认同需求,分别含3个条目、3个条目和5个条目。结论 该研究形成的全科住培医师职业内驱力量表结构合理,具有良好的信效度,适用于全科住培医师职业内驱力测评,为住培医师职业教育提供指引。  相似文献   
42.
Summary Lung specimens from 39 nickel refinery workers autopsied during the period from 1978 to 1984 were analyzed for nickel. Fifteen of the workers were employed in the Roasting and Smelting Department, where exposure to nickel was predominantly in the form of nickel-copper oxides, Ni3S2 and metallic dust. The remaining 24 men worked in the Electrolysis Department. Exposure in this group was considered to be mostly to the water-soluble compounds, NiSO4 and NiCl2, but also to a lesser degree to water-insoluble nickel compounds such as nickel-copper oxides and sulphides. The arithmetic mean ± SD for nickel concentration in lung tissues expressed in gg–1 dry wt for the 39 workers was 150 ± 280. In the workers employed in the Roasting and Smelting Department, the average nickel concentration was 330 ± 380; for those who worked in the Electrolysis Department it was 34 ± 48. Lung tissue from 16 autopsied persons not connected with the refinery had an average nickel concentration of 0.76 ± 0.39. Statistical analysis based on log-normal distributions of the measured nickel concentrations allowed three major conclusions to be formulated: (1) nickel refinery workers exhibit elevated nickel levels in lung tissues at autopsy; (2) workers of the Electrolysis Department and the Roasting Smelting Department constitute distinct groups with respect to the accumulation of nickel in lung tissue; (3) workers who were diagnosed to have lung cancer had the same lung nickel concentrations at autopsy as those who died of other causes.  相似文献   
43.
We investigated muscle strength, aerobic power, and occupational and leisure-time physical loading as predictors of back pain in a 5-year follow-up study. A cohort of 456 adults aged 25, 35, 45 and 55 years, free of back pain, participated in measurements of anthropometric characteristics, aerobic power and muscle strength characteristics at baseline. The subjects' levels and types of physical activity and occupational physical loading were also determined. At 5 years after the baseline examinations 356 of these subjects (78.1 %) were reached by mail, and 262 of them (73.6%) properly completed and returned a questionnaire including a detailed back pain history for the 5 years following the baseline measurements. Of this number 56 subjects (21 %) who reported back pain ( > 30 on a scale from 0 to 100) and functional impairment during the 5-year follow-up composed the marked back pain group. Other subjects (n = 71, 27%) noting lesser symptoms were included in the mild back pain group; 135 subjects (52%) reported having had no back pain. The subjects with marked back pain were on average taller than the subjects without back pain, while no such difference was found in body mass. Heavy occupational musculoskeletal loading (P = 0.005) and high general occupational physical demands (P = 0.036) predicted future back pain. Leisuretime physical activity, aerobic power or muscle strength characteristics were not predictive of future back pain.  相似文献   
44.
The spectral distributions of a range of dental photocuring sources were measured at the exit window and at a distance of 10 cm. The former enabled the evaluation of a newly proposed photocuring efficiency index which correlates well with the depth of cure of the photopolymerized resins, thus providing a basis for the comparison of different photocuring sources. The spectral irradiante of the sources obeyed the inversesquare law, allowing a comparison with the ACGIH threshold limit values. According to these criteria, no ocular hazard is posed to the patient or clinician by u.v.-A or u.v.-B radiation nor to the patient by the visible light when momentarily exposed to the sources. Similarly the ACGIH criterion indicates that the clinician does not risk chorioretinal injury provided the exposure is restricted to less than 140 s in a 3 h period.  相似文献   
45.
Low-frequency and transient magnetic fields of moderate flux densities are known to generate visual phenomena, so-called magnetophosphenes. In the present study, time-variable very low frequency (10–50 Hz) electromagnetic fields of moderate flux density (0–40 mT) were used to induce magnetophosphenes. The threshold values for these phosphenes were determined as a function of the frequency of the magnetic field both in normal subjects and colour defective ones. Maximum sensitivity occurred at a frequency of approximately 20–30 Hz, and with broad-spectrum light the threshold flux density was 10–12 mT. The threshola values were found to be dependent upon the intensity and the spectral distribution of the background light. Sensitivity decreased during dark adaptation. In certain respects deutans differed from subjects with normal colour vision. Possible mechanisms for generation of magnetophosphenes are discussed. The present magnetic threshold curves show a close resemblance to corresponding curves obtained by electric stimulation at various frequencies provided the electric thresholds are divided by the a.c. frequency. These problems are under current investigation in our laboratory. This is in full agreement with the assumption that the fluctuating magnetic field affects retinal neurons by inducing currents which polarise synaptic terminals.  相似文献   
46.
Summary In a 61-year-old woman, who had been exposed for 20 years to cadmium in the production of Ni-Cd batteries, nephrectomy of the contracted kidney was performed. The removed kidney was examined histologically and the cadmium concentration was determined in the cortex (44.97 g g–1) and in the medulla (7.71 g g–1). The homogenates of the renal cortex and medulla were subjected to gel filtration on Sephadex G-75. In the cortex, as well as the medulla, cadmium was predominantly found in the low-molecular (metallothionein) fraction, but in the cortex, Cd content in this fraction was six times higher than in the medulla. The determination of SH groups and proteins in high- and low-molecular fractions indicates an induction of the metallothionein formation primarily in the renal cortex.  相似文献   
47.
医务人员的身心健康和执业满意度直接影响医疗服务质量。复旦大学附属华山医院从员工需求切入,建立并实施员工关爱计划:横向包括身心健康、社会支持、个人成长与职业生涯发展等;纵向贯彻危机前、危机中、危机后三级援助体系。实践后,员工满意度、社会支持水平、幸福感有所提升,职业倦怠阳性率有所下降。员工关爱计划在管理理念、方案完善、人才培养等方面还有待进一步改进。  相似文献   
48.
目的 利用项目反应理论(item response theory,IRT)对《中国版职业紧张核心量表》质量进行分析与评价,为后期量表使用和修订提供参考依据。方法 采用方便抽样方法,抽取湖北省两家三甲医院和多家一、二级医院共1261名医务人员作为研究对象,应用《中国版职业紧张核心量表》调查其职业紧张情况。采用主成分分析验证量表4个维度的单维性。采用IRT中的Same Jima等级反应模型计算每个条目的区分度、难度系数和信息量,从微观角度评价量表的测量特性。结果 量表4个维度均满足单维性假设。IRT结果显示所有条目的区分度较好,取值范围在0.67~3.10;17个条目中有13个条目的难度系数在-2.78~2.30之间,且不存在难度逆反现象,条目9和11难度过高且难度逆反,条目15和16难度过低过高并存且有难度逆反现象,提示待改进;除了条目9、11和15提供的信息量中等,条目16和17提供的信息量较差以外,其余条目的信息量均较好。结论 《中国版职业紧张核心量表》所有条目的区分度较好。从难度系数和信息量两个角度,条目9、11、15、16、17的测验质量均是有待改进的,其余条目性能良好,建议针对上述分析结果结合专家意见对问题条目进行修订。  相似文献   
49.
目的了解某钢丝绳生产企业职业病危害现状,为控制该企业职业病危害因素提供依据。方法通过对某钢丝绳生产企业进行职业卫生现场调查、职业病危害因素检测,收集有关数据和资料,结合职业病危害防护设施、个人职业病危害防护、应急救援措施、职业健康检查结果等进行分析评价。结果粉尘、毒物、高温检测结果均符合国家职业卫生标准,合绳捻股车间捻股机、合绳机岗位噪声强度检测结果超标率100%,拉丝车间噪声检测合格率16.7%。职业卫生管理措施不够完善。结论该公司属于职业病危害较重企业,劳动者有发生职业性慢性铅中毒、职业性化学性灼伤、职业性噪声聋的风险,需采取有效措施进行整改。  相似文献   
50.
目的探讨石家庄市居民慢性阻塞性肺疾病检出情况及影响因素。方法2021年9—12月采用整群随机抽样方法抽取石家庄市3个社区,对抽中社区的所有居民进行问卷调查和肺功能检查。利用描述流行病学方法分析社区人群慢性阻塞性肺疾病患病现状。应用单、多因素方法分析影响慢性阻塞性肺疾病发生的危险因素。结果共2348名居民完成问卷调查和肺功能检查,其中男1205人,占51.32%,女1143人,占48.68%,年龄31~76岁。共有146例检出慢性阻塞性肺疾病,检出率为6.22%,其中轻度69例,占47.26%,中度54例,占36.99%,重度23例,占15.75%,未检出极重度者。检出来的症状分布中,以咳嗽及咳痰的比例较高,分别为52.05%(76例)和49.32%(72例)。多因素Logistic回归分析结果显示年龄≥40岁(OR=1.705、1.936)、男性(OR=3.404)、居住在农村(OR=2.469)、偶尔或经常吸烟(OR=1.592、1.800)、有职业粉尘接触史(OR=2.179)、有哮喘家族史(OR=3.164)、有慢性阻塞性肺疾病家族史(OR=5.170)、有呼吸道反复感染史(OR=3.414)是石家庄市居民慢性阻塞性肺病患病的影响因素。结论石家庄市居民的慢性阻塞性肺疾病患病情况不容乐观,且危险因素众多。重点针对中老年、吸烟、农村、有各种相关家族史的男性高危人群开展早期筛查和采取针对性干预措施,有助于对居民慢性阻塞性肺疾病进行防控。  相似文献   
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