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951.
A historical mortality study of a cohort of employees of a gold mining and refining company was carried out in Salsigne, France. A major goal of the study was to investigate the relationship between lung cancer mortality and exposure to arsenic, radon, silica, and other contaminants of the working environment. A twofold excess of lung cancer was found both among miners and smelters, mainly concentrated among workers who had experienced exposure to past levels of arsenic, radon, and silica. The consistency of the results in the mine and the refinery are suggestive of a carcinogenic risk from both soluble and insoluble arsenic, although the potential role of other factors cannot be dismissed. © 1994 Wiley-Liss, Inc.  相似文献   
952.
A new mutant, the Eisai hyperbilirubinemic (EHB) rat, shows no inherent expression of the canalicular isoform of the multidrug resistance protein (cMrp) in the liver. It has defective biliary secretion of organic anions such as bilirubin glucuronides, bromosulfophthalein (BSP), cysteinyl leukotrienes, glutathione (GSH) and bile acid sulfate and glucuronides. When rats were injected intravenously with CdCl2, biliary excretion of Cd over 30 min was 0.28% and 0.004% of the total dose in Sprague-Dawley (SD) and EHB rats, respectively. Six SD rats and five EHB rats were fed a diet containing Cd. Bile Cd was detected at the level of 2 ng/20 min in SD rats, but not in EHB rats. There was no significant difference of hepatic Cd concentration between SD and EHB rats. Furthermore, there were no significant differences of renal and intestinal Cd, and hepatic and renal metallothionein (MT) concentrations between the SD and EHB groups. Biliary excretion of reduced-GSH for 20 min was 1.3 ± 0.3 mg and 3.6 ± 0.9 μg in SD and EHB rats, respectively. Our results suggest that hepatobiliary excretion of exogenous Cd is mediated mainly via carrier transport, including a cMrp or GSH carrier, but that the lack of the transport pathway does not contribute to abnormal accumulation of Cd in the liver. Received: 12 August 1996 / Accepted 7 November 1996  相似文献   
953.
Previous study has shown that α2D-adrenoceptors are involved in modulation of peristalsis in the rat ileum. The aim of the present study was to determine the tissue location of α-adrenoceptors in the rat ileum by using a recently devised method. The pre-synaptic α-adrenoceptors were characterised by measuring the potencies of agonists to inhibit transmurally-evoked (1 ms pulses, 10 Hz, 8-10 s trains) contractions of the longitudinal and circular muscles and the affinities of antagonists. Post synaptic α-adrenoceptors were identified by screening agonists and antagonists in carbachol-contracted tissues. In the circular muscle the order of potencies for inhibiting transmurally-induced contraction was: clonidine ≥ oxymetazoline ≥ UK 14,304 ≥ guanfacine > talipexole > phenylephrine > azepexole. The potency ratios relative to clonidine correlated to those previously derived using the rat ileum peristaltic reflex preparation. Most of the α-adrenoceptor agonists, however, caused only small inhibitions of the longitudinal muscle contraction in response to transmural stimulation, except phenylephrine and azepexole. RX 821002, yohimbine, rauwolscine, BRL 44408, phentolamine, idazoxan, ARC 239, and prazosin inhibited the effect of clonidine on the circular muscle response with apparent pKB values best correlated with pKB or pKi values derived from the rat ileum peristaltic reflex preparation and other tissues known to have the α2D-subtype. The rank order of potencies at inhibiting carbachol-induced responses of both muscle layers was: phenylephrine ≥ oxymetazoline > clonidine ≥ talipexole > azepexole >> guanfacine. UK 14,304 was inactive up to 10 μM. The EC50 value of each agonist on the longitudinal muscle was not significantly different to the corresponding value on the circular muscle. Prazosin was more potent than yohimbine at inhibiting the relaxant effect of phenylephrine in both muscle layers of carbachol-contracted tissues. It is concluded that the recently identified α2D-adrenoceptors of the rat ileum are located on cholinergic neurons controlling circular muscle contraction. The study also demonstrated the presence of postsynaptic α1-adrenoceptors involved in mediating relaxation in both muscle layers. Received: 4 November 1996 / Accepted: 10 April 1997  相似文献   
954.
天麻素对缺血再灌注神经细胞膜的保护作用   总被引:36,自引:0,他引:36  
用新生Wistar大鼠大脑皮层进行神经细胞培养 ,将培养 8d的神经细胞置于模拟“缺血”状态下 ,5h后神经细胞发生肿胀 ,胞内乳酸脱氢酶 (LDH)漏出增加 ,膜流动性下降、脂质过氧化(LPO)含量增加 ;将经过“缺血”损伤神经细胞置 1 8h模拟“再灌注” ,“再灌注”后细胞数目明显减少 ,LDH的漏出、膜流动性下降和LPO增加继续加重 ,说明细胞损伤进一步加重。经过天麻素孵育后的神经细胞“缺血”或“再灌注”后LDH的漏出及LPO含量明显低于损伤组 ,而膜流动性则明显高于损伤组。表明 :天麻素对体外培养神经细胞的缺血再灌注损伤有保护作用  相似文献   
955.
Caring and cancer nursing: framing the reality using selected social science theory Despite the recent interest in caring for both academic and clinical nursing, the theoretical basis of this concept may appear somewhat elusive as the research and debate vary widely in their focus. As a result, the available literature may fail to consider the specific contextual issues which characterize caring as it is understood across different health care settings. Consideration of theory from disciplines close to nursing, it is suggested, may be useful in understanding the nature of such 'real world' caring. In this discussion the concept of caring within cancer nursing is explored by drawing on a number of social science and nursing sources. It is known that cancer provokes unique caring demands for nurses practising in this area. By examining the context of cancer, it is argued that effective caring deserves to be recognized as an important clinical variable which can influence a diverse range of issues such as patient satisfaction or therapeutic outcome. It is suggested that other nursing specialisms should also explore the psychosocial dimensions of caring in relation to their own role.  相似文献   
956.
In this article we present a patient with acute lymphoblastic leukemia (ALL) associated with eosinophilia, in which the eosinophilia preceded a meningeal and bone-marrow relapse of ALL. We analysed the purine and pyrimidine nucleotide content of the eosinophils (92% pure) and compared the nucleotide pattern with that of eosinophils from healthy donors and from patients with eosinophilia not associated with leukemia. The ratios of purine : pyrimidine and of uracil :cytosine nucleotides were decreased compared with those in eosinophils from healthy donors and from patients with eosinophilia with other aetiologies. The total nucleotide concentration was increased, especially the concentration of UDP-sugars and pyrimidine nucleotides.

The decrease in these ratios and the increase in concentration of the nucleotides and the UDPsugars were also detected in leukemic cells of patients with ALL (de Korte et al., Leukemia Res. 10, 389–396 (1986)) compared to normal lymphocytes. We suggest a malignant character of the eosinophils in our patient with ALL associated with eosinophilia, in contrast with the nonmalignant state suggested previously for these cells.  相似文献   

957.
We report the collaboration between the First Postgraduate School of Obstetrics and Gynecology at the University of Milan, Italy, and the nongovernmental organization “Emergency” that operates through its own hospitals in countries devastated by armed conflicts. The collaboration was centered on the maternity clinic that Emergency opened in 2003 in northern Afghanistan. After a woman resident spent 5 months on-site, the collaboration is now extended to all residents with a group with four areas of intervention: guidelines, clinical records and data collection, drugs and medical devices, and teaching material. In addition, it offers consultation by e-mail for any clinical issue that might arise.  相似文献   
958.
A group of 153 children (51 with a history of bronchiolitis and 102 matched controls) were evaluated in a historical cohort study at a mean age of 8 years and again at 13 years to test the primary hypothesis that mild bronchiolitis, far more common than severe (hospitalized) bronchiolitis, predicts wheezing. A secondary hypothesis was that passive smoking also predicts wheezing. Many potentially confounding variables such as family history of asthma were controlled in analyses. Analysis at 13 years produced results that were not anticipated from previous analysis of interviews at age 8. Although mild bronchiolitis was a powerful predictor of wheezing at age 8 years, it was no longer a strong predictor of wheezing at age 13 in either bivariate or multivariate analysis. Although epidemiologic studies, by their nature, cannot prove causality, findings are consistent with the hypothesis that sequelae often follow mild bronchiolitis but diminish during childhood. Maternal smoking was a powerful predictor of wheezing at age 13 in bivariate analysis (Kendall's Tau B = 0.19, P less than 0.01) and in multivariate analysis (odds ratio = 2.67, P less than 0.01). In children at highest risk for wheezing, males with a family history of asthma, multivariate analysis suggested that maternal smoking is associated with an increase in wheezing from 36% to 60%. We conclude that passive smoking, previously identified as a risk factor in this population for both bronchiolitis in infancy and wheezing at age 8, is a risk factor for wheezing-associated morbidity throughout the childhood years.  相似文献   
959.
护理学基础课程技术操作教学改革与实践   总被引:1,自引:0,他引:1  
目的培养高素质实用型护理人才,塑造护生良好形象,使之更加适应现代护理工作需要。方法教师在护理学基础课程技术操作教学过程中,注意通过课前引导学生预习操作内容、精心设计教案、规范操作流程、善于灵活运用示教和多媒体、演练情景剧、开放实验室、强化训练、开展技能考核与比赛等方式培养学生动手操作能力。结果2001年以来,已先后有3届学生进入临床实习。通过问卷调查,学生、带教教师、病人满意度分别达到98.5%、98.2%、97.0%。  相似文献   
960.
阮鹏 《实用预防医学》2007,14(2):577-578
当代大学生手淫行为比较普遍,很多大学生在上大学之前就养成了难以自控的手淫习惯。大学生手淫既影响了他们的身心健康,对他们在校园里健康成长成材也构成了严重的威胁。从思想与心里教育角度引导大学生正确对待手淫,促使他们养成积极健康的生活习惯,对他们将来人生的健康发展及营造和谐的校园风气具有重要的作用。文章论述了当代大学生手淫的根源、手淫危害、诱发因素、手淫动机及预防、矫治措施。  相似文献   
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