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21.
目的:揭露胡永才虚假文章的事实真相,消除负面影响。方法:对“湿润烧伤膏治疗烧伤总面积>50%TBSA患者的疗效观察”一文的课题设计、处理因素、效应指标、统计方法及论文写作等内容进行全面剖析。结果:课题设计违背了科研原则,观察组与对照组处理因素随意性太大,效应指标缺乏可信性,诊断依据不标准,统计学概念不清,论文写作不规范。结论:论文内容失真,不能代表总体样本真实情况。 相似文献
22.
Violence at the workplace--a questionnaire survey of nurses. 总被引:2,自引:0,他引:2
Dorota Merecz Joanna Rymaszewska Agnieszka Mo?cicka Andrzej Kiejna Joanna Jarosz-Nowak 《European psychiatry》2006,21(7):442-450
BACKGROUND: In the health sector, anywhere in the world nurses are one of the most exposed groups to violence. However, it is not obvious that psychiatric nurses (PNs) are more exposed to aggression and burnout. OBJECTIVES: To determine the nature and effects of aggressive acts towards nursing staff in psychiatric and other medical services in Poland. METHODS: Various questionnaires (Stress at Work Scale, General Health Questionnaire, Maslach Burnout Inventory, Work Satisfaction Scale), were distributed among psychiatric (N=78) and non-psychiatric nurses (N-PNs) (N=335). A 92.6% response rate was achieved. RESULTS: Significant differences were found between PNs and non-psychiatric counterparts with respect to their experiences of violence. The most frequently reported incident was verbal abuse, followed by threats and physical assault. Patients were significantly more frequent perpetrators in psychiatric wards than in others. The level of intra-staff aggression did not significantly vary between groups, neither did the level of work satisfaction and absenteeism. CONCLUSION: The frequency of violent acts and stress related to them point out the strong need for the development of preventive programs to address the issue of violence at work. 相似文献
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Chang Hyun Lee Jung-Gi Im Jin Mo Goo Hyun Ju Lee Sung-Tae Hong Cheng Hua Shen Doo Hyun Chung Kyu Ri Son Jung Min Chang Hong Eo 《Korean journal of radiology》2007,8(5):372-381
OBJECTIVE: To investigate the serial CT findings of Paragonimus westermani infected dogs and the microscopic structures of the worm cysts using Micro-CT. MATERIALS AND METHODS: This study was approved by the committee on animal research at our institution. Fifteen dogs infected with P. westermani underwent serial contrast-enhanced CT scans at pre-infection, after 10 days of infection, and monthly thereafter until six months for determining the radiologic-pathologic correlation. Three dogs (one dog each time) were sacrificed at 1, 3 and 6 months, respectively. After fixation of the lungs, both multi-detector CT and Micro-CT were performed for examining the worm cysts. RESULTS: The initial findings were pleural effusion and/or subpleural ground-glass opacities or linear opacities at day 10. At day 30, subpleural and peribronchial nodules appeared with hydropneumothorax and abdominal or chest wall air bubbles. Cavitary change and bronchial dilatation began to be seen on CT scan at day 30 and this was mostly seen together with mediastinal lymphadenopathy at day 60. Thereafter, subpleural ground-glass opacities and nodules with or without cavitary changes were persistently observed until day 180. After cavitary change of the nodules, the migratory features of the subpleural or peribronchial nodules were seen on all the serial CT scans. Micro-CT showed that the cyst wall contained dilated interconnected tubular structures, which had communications with the cavity and the adjacent distal bronchus. CONCLUSION: The CT findings of paragonimiasis depend on the migratory stage of the worms. The worm cyst can have numerous interconnected tubular channels within its own wall and these channels have connections with the cavity and the adjacent distal bronchus. 相似文献
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Min Zhang Wen-Bin Li Jin-Xia Geng Qing-Jun Li Xiao-Cai Sun Xiao-Hui Xian Jie Qi Shu-Qin Li 《Journal of cerebral blood flow and metabolism》2007,27(7):1352-1368
Glial glutamate transporter-1 (GLT-1) plays an essential role in removing glutamate from the extracellular space and maintaining the glutamate below neurotoxic level in the brain. To explore whether GLT-1 plays a role in the acquisition of brain ischemic tolerance (BIT) induced by cerebral ischemic preconditioning (CIP), the present study was undertaken to observe in vivo changes in the expression of GLT-1 and glial fibrillary acidic protein (GFAP) in the CA1 hippocampus during the induction of BIT, and the effect of dihydrokainate (DHK), an inhibitor of GLT-1, on the acquisition of BIT in rats. Immunohistochemistry for GFAP showed that the processes of astrocytes were prolonged after a CIP 2 days before the lethal ischemic insult, which could protect pyramidal neurons in the CA1 hippocampus against delayed neuronal death induced normally by lethal ischemic insult. The prolonged processes extended into the area between the pyramidal neurons and tightly surrounded them. These changes made the pyramidal layer look like a 'shape grid'. Simultaneously, the prolonged and extended processes showed a great deal of GLT-1. Western blotting analysis showed significant upregulation of GLT-1 expression after the CIP, especially when it was administered 2 days before the subsequent lethal ischemic insult. Neuropathological evaluation by thionin staining showed that DHK dose-dependently blocked the protective role of CIP against delayed neuronal death induced normally by lethal brain ischemia. It might be concluded that the surrounding of pyramidal neurons by astrocytes and upregulation of GLT-1 induced by CIP played an important role in the acquisition of the BIT induced by CIP. 相似文献
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观察126例人类转移癌,分析比较淋巴样细胞浸润(LI)程度与患者年龄、病理类型、组织分化和核异型程度的关系。结果表明:患者年龄及病理类型与LI程度无关;组织分化程度在LI上虽有差别,但无对应性关系;而核异型程度与LI关系密切。核异型性愈明显,LI程度愈高,反之亦然。这说明核分级不仅可以反映宿主免疫反应的高低,也可提示转移癌抗原性的强弱。 相似文献
29.
X F Sun H Zhang X C Wu Y M Han G Q Hou M S Xian 《Acta oncologica (Stockholm, Sweden)》1992,31(1):37-40
The microcirculatory architecture of normal tissue, transitional mucosa and adenocarcinoma of the human colon was investigated with microvascular corrosion casting (MVCC) combined with scanning electron microscopy (SEM). The study showed that the capillaries within the normal mucosa were arranged in a regular hexagonal pattern around the mucosal glands and that the microvessels of transitional mucosa mostly had lost the typical hexagonal pattern and become slightly wider in diameter. The microvessels in the tumor periphery were increased in number and disorganized, and presented large variation in morphology with claw-like formations, widened sinuses, diverticula and appendixoid patterns. Microvessels were lacking in the central areas of tumors. These morphological alterations may serve as additional indicators of tumor development. 相似文献
30.
中药黄精中的新生物碱 总被引:10,自引:0,他引:10
中药黄精中的新生物碱孙隆儒1)王素贤李铣(沈阳药科大学天然药物研究室,沈阳110015)黄精为百合科黄精属植物黄精(PolygonatumsibiricumRedoute)的根茎,具有补气养阴、FigStructureofthecompound健脾、... 相似文献