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51.
The present study examined four potential roles of work-related negative affectivity on the associations between self-reported occupational stress and physical well-being among telecommunication employees in Greece. Participants (764, predominantly male) completed a battery of self-report measures on perceived occupational stress, negative affectivity, and illness symptoms. In line with previous research, negative affectivity exerted a nuisance effect, by inflating the association between reported stressors and illness symptoms, and significantly predicted illness symptoms, over and above the effects of stressors. In addition, negative affectivity influenced reported illness symptom indirectly, through the effects of stressors, and moderated the relationship between interpersonal conflict at work and illness symptoms. The findings suggest that negative affectivity can largely explain and influence in different ways the associations between self-reported stress and physical strain. It is recommended that future studies of occupational stress should control for the effects of negative affectivity, and that health professionals should be cautious of its effects when interpreting relationships between self-reported occupational stress and physical well-being.  相似文献   
52.
负性生活事件对抑郁症患者血清细胞因子水平的影响   总被引:9,自引:0,他引:9  
目的 探讨负性生活事件对抑郁症患者血清细胞因子水平的影响。方法 采用酶联免疫吸附法 (EL SIA)对有负性生活事件诱因的抑郁症患者 2 3例、无诱因的抑郁症患者 2 9例和 2 9名正常人的血清白介素 2 (IL 2 )、可溶性白介素 2受体 (sIL 2R)、白介素 10 (IL 10 )和白介素 12 (IL 12 )水平进行检测。结果  3组间IL 2、sIL 2R及IL 12水平存在显著性差异 ,而IL 10则 3组间无显著性差异 ,有负性生活事件诱因组IL 2及sIL 2R水平明显低于无诱因组和对照组 (P <0 0 1) ;有诱因组其负性生活事件对患者心理活动影响的严重程度与IL 2和sIL 2R水平呈负相关(P <0 0 5 )。结论 负性生活事件对抑郁症患者的细胞免疫激活系统有抑制作用 ,IL 2可能是起主要的中介作用。  相似文献   
53.
目的 :SS研究大鼠脊髓压迫损伤减压后钙离子和兴奋性氨基酸变化及其与神经功能恢复的关系 .方法 :将动物随机分为 :慢性渐进性脊髓损伤组 ,慢性渐进性脊髓损伤减压 1,7,14 ,2 8d组 .取伤段脊髓 ,用高效液相色谱法检测谷氨酸和天门冬氨酸的含量的变化 ,用原子吸收光谱法测定其离子改变及水含量 .结果 :慢性渐进性脊髓损伤减压后钙离子和兴奋性氨基酸有明显的降低 ,减压后 1,7,14 ,2 8dGlu(μmol·g-1)分别为 :6 .16± 0 .16 ,5 .4 3± 0 .2 2 ,5 .4 3± 0 .17,5 .33± 0 .2 0 ;Asp(μmol·g-1)分别为 :3.39± 0 .12 ,2 .96±0 .11,2 .92± 0 .16 ,2 .89± 0 .15 ;Ca2 + 离子 (μmol·kg-1)分别为 :5 .84± 0 .11,5 .33± 0 .10 ,5 .2 8± 0 .17,5 .2 4± 0 .0 2 .它们均较减压前 (Glu为 6 .32± 0 .10 μmol·g-1,Asp为 3.5 6±0 .13μmol·g-1,Ca2 + 为 6 .5 3± 0 .6 4 μmol·kg-1)有显著降低 (P <0 0 5 ) ,其中前 7d降低较快 ,以后有降低不明显 .减压后 1,7,,14 ,2 8d改良的Tralov评分分别为 3.5 3± 0 .11,3.74± 0 .12 ,3.86± 0 .12 ,3.88± 0 .10 ;斜板试验分别为 4 3.3± 2 .3,4 6 .2± 1.1,4 8.8± 2 .8,4 9.7± 2 .6 ,均较减压前Tralov评分 (3.4 0± 0 .13)斜板试验 (40 .9± 1.8)有显著升高  相似文献   
54.
首次CT检查阴性的颅脑损伤54例临床分析   总被引:2,自引:0,他引:2  
目的分析颅脑损伤首次CT检查阴性而复查CT阳性的表现和原因。方法通过对首次CT检查阴性而复查CT阳性的54例颅脑损伤患者(研究组)的临床资料进行回顾性分析总结,并与同期收治的325例首次CT及复查CT均为阴性的颅脑损伤患者(对照组)作比较。结果研究组首次CT检查阴性而复查CT阳性表现为迟发性血肿、脑挫裂伤、脑积水、硬膜下积液、弥漫性脑肿胀、外伤性脑梗塞等,可由不同原因引起。结论熟悉本类颅脑损伤首次CT检查阴性,而复查CT阳性的表现及原因,对于指导检查及治疗,改善病人预后有重要意义。  相似文献   
55.
Summary The induction time for amorphous calcium phosphate (ACP) phase transformation was monitored at pH 7.4 and T=25°C with [Ca2+]0=[PO4]0=4.0×10−3 M, as a function of added crystal growth inhibitors Mg2+, Sr2+, Zn2+, pyrophosphate (PP), and tripolyphosphate (TPP). Metal ions increase the induction time for the initiation of the phase change reaction in the order Zn2+<Sr2+<Mg2+. For polyphosphates it was observed that both PP and TPP are potent inhibitors with TPP more effective than PP as expected. The combination of Mg2+ or Sr2+ and PP or TPP leads to a synergistic delay in the onset of the phase conversion. The greatest inhibition was observed for Mg2+ and TPP. Reaction solutions containing 2.0×10−4 M Mg2+ and 4.0×10−5 M TPP resulted in a 90% increase in the induction time over what would be anticipated from an additive effect from these species.  相似文献   
56.
57.
煤烟型大气污染对儿童肺功能的影响   总被引:4,自引:1,他引:3  
为观察煤烟型大气污染对儿童健康的影响 ,选择了太原市 3个污染程度不同地区的 45 0名儿童进行肺功能测试和问卷调查。研究结果显示 ,儿童呼吸功能表现为重度污染区 <中度污染区 <相对清洁区 ;肺通气功能阻塞性异常率表现为重度污染区 >中度污染区 >相对清洁区 ;Logistic回归分析发现肺通气功能阻塞性异常率与小学生家庭的取暖方式、厨房和卧室是否分开以及污染物的水平有关 ;多元线性回归分析显示重度污染区儿童的FVC、FEF5 0与相对清洁区相比分别减少了 65 80ml、119 2 7ml,中度污染区儿童的FVC、FEF5 0与相对清洁区相比分别减少了 5 7 2 8ml和 114 2 9ml;Ln(SO2 )每升高一个单位 ,FVC和FEF5 0分别减少69 10ml和 119 79ml,Ln(PM1 0 )每升高一个单位 ,FVC、FEF5 0等分别减少了 193 5 0ml和 171 69ml。结果提示 ,太原市煤烟型大气污染对儿童呼吸系统产生了危害。  相似文献   
58.
A follow-up investigation was performed on 49 female workers studied 2 years earlier in a vegetable-pickling plant. Acute and chronic respiratory symptoms and ventilatory capacity measurements were recorded during the original and the follow-up studies. Maximal expiratory flow-volume (MEFV) curves were recorded during the Monday morning work shift. The forced vital capacity (FVC), 1-s forced expiratory volume (FEV1), and flow rates at 50% and the last 25% of the FVC (FEF50, FEF25) were measured. There were small increases in the prevalence of chronic symptoms between the two studies for both smokers and nonsmokers, but these did not reach statistical significance. Five workers at the time of the initial study had a diagnosis of occupational asthma; only one of these was still working at the time of follow-up. Workers lost to the follow-up had lower lung function than those seen at follow-up. In workers who were followed, larger than expected mean annual declines were noted for all ventilatory capacity parameters in both smokers (FVC 0.070 l, FEV1 0.070 l; FEF50 0.355 l/s, FEF25 0.270 l/s) and nonsmokers (FVC 0.045 l, FEV1 0.045 l, FEF50 0.285 l/s; FEF25 0.130 l/s). The decrease was particularly pronounced for FEF50 and FEF25. The accelerated decline in ventilatory capacity tests noted in the female nonsmokers suggests an independent effect on lung function of work exposure in this environment. Our data confirm that work in the pickling industry, particularly in small, poorly regulated plants, has deleterious effects on respiratory function. Received: 24 September 1996 / Accepted: 19 June 1997  相似文献   
59.
A chromium electroplating worker, suffering from epistaxis during work, was found to have nasal septum perforation. To determine the etiology and prevalence of nasal septum lesions, we conducted a survey of seven chromium electroplating factories and examined 79 workers. Forty workers from three aluminum electroplating factories were also enrolled as the reference group. Subjects were thoroughly examined by an otolaryngologist and each of them provided a blood and urine sample. A questionnaire interview regarding symptoms of the upper respiratory tract, past medical history, life style, and work history was also conducted. Air chromium concentrations were measured by taking area samples for 4–6 hours. Based on field observation and chromium measurements, we divided chromium electroplating into three different exposure zones: workers directly dealing with electroplating tanks (n = 31), other process workers (n = 29), and office workers and drivers (n = 19). Among the 79 chromium electroplating workers, there were 16 cases of nasal septum perforation, and 42 with either scar formation or ulceration; 10 chromium electroplating workers developed skin ulcers after performing chrome plating. No workers from aluminum electroplating factories had any nasal septum or skin abnormalities. There was a consistent trend between the degree of chromium exposure and the signs and symptoms related to the nose, throat, and skin. Immediate improvement of occupational hygiene is warranted.  相似文献   
60.
1. Endothelium-derived nitric oxide (NO) is a potent vasodilator. Because the body oxidizes it to nitrate ions, NO3-, measurement of the serum concentration and the urinary excretion of NO3- may be an index for endogenous NO. We investigated the role of NO on hyperdynamic circulation in cirrhotic and partial portal vein-ligated rats by measuring NO3. 2. Liver cirrhosis was induced by administration of thioacetamide. Systemic and splanchnic haemodynamics and splenic-systemic shunting were determined by tracer microspheres. The concentration of NO3- was measured by using high-performance liquid chromatography with an anion-column. 3. We found that systemic and splanchnic hyperdynamic circulation existed to almost the same extent in cirrhotic and in portal vein-ligated rats as compared to the controls and sham-operated rats, respectively. Splenic-systemic shunting was markedly greater in portal vein-ligated rats than in cirrhotic rats. 4. Serum NO3- levels and urinary excretion of NO3- in cirrhotic rats tended to increase as compared to the controls. On the other hand, the levels in portal vein-ligated rats were significantly increased as compared to those of the sham-operated rats, and were significantly and negatively correlated to the splanchnic arterial resistance and total vascular resistance. The amount of urinary excretion of NO3- significantly correlated to splenic-systemic shunting (r = 0.61, P<0.05) only in portal vein-ligated rats. 5. We suggest that these high levels of NO3- in portal vein-ligated rats relate to the extensive formation of porto-collateral vasculature or acute changes in systemic and splanchnic haemodynamics due to portal vein-ligation.  相似文献   
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