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21.
In a series of 51 children presenting with an accidental caustic burn, symptoms were analysed for their predictive value of significant i.e. necrotizing oesophageal lesions (grade II or III). For the whole group, the incidence of significant oesophageal lesions was 37%. Vomiting and/or respiratory distress were associated with high incidence of significant oesophageal burn (84% and 75% respectively). The particular location of each caustic burn was analysed for its association with caustic burns at other anatomical sites. Of the 18 patients with a laryngeal burn, 72% also had a grade II or III oesophageal burn. The 19 patients with a grade II or III oesophageal burn and the 18 patients with a laryngeal burn, all had lesions at other sites. In the group of 19 patients with a caustic lesion limited to one site, only 1 patient showed mild oesophagitis (grade I) without late sequelae.  相似文献   
22.
选用无毒、无免疫原性的高分子化合物聚乙二醇(PEG)为修饰剂,以活性酯法制备出PEG- 重组人超氧化物歧化酶(PEG-rh SOD)共价结合物.修饰酶的生物半衰期为15h,比修饰前延长了90倍,对酸、碱、热的耐受力明显高于修饰前.用照射小鼠的活存率评价了PEG-rhSOD的辐射防护作用.小鼠受8.5Gy γ射线照射前1h腹腔注射30万U/kg PEG-rh SOD,可提高活存率42%,与未修饰的rhSOD相比,活存率提高14%.实验仍在进行中.  相似文献   
23.
Summary In a cross-sectional study, 65 workers in the chemical industry with exposure to platinum salts were investigated with regard to the prevalence to allergic respiratory tract diseases. A respriatory questionnaire, a skin-prick test with K2PtCl6 and environmental allergens, determination of total IgE, platinum-specific IgE and histamine release in basophilic granulocytes and lung function tests were applied before and after a Monday shift and after a Friday shift. Work-related symptoms of respiratory allergy were present in 23% of all workers, but were significantly more frequent in the most exposed group in the platinum refinery (52.4%). Of all workers, 18.7% had a positive skin-prick test with platinum salt. As compared to the other workers, the workers with work-related symptoms of respiratory allergy had significantly more positive skin-prick tests (64.3%) and a higher total IgE and platinum-specific IgE; they did not, however, show higher histamine release. In the course of the week, a significant fall in lung function, namely in FEV1 and FEF25, was recorded in the group of workers with work-related symptoms.  相似文献   
24.
某化工厂1987~2000年164例工伤事故调查分析   总被引:2,自引:0,他引:2  
目的调查分析某化工厂工伤事故的分布规律及其危险因素,以便采取相应的预防干预措施。方法对1987~2000年该化工厂发生的工伤事故进行回顾性调查分析,建立数据库,并统计分析。结果 ①事故以轻伤为主,约占80.0%。②事故类别主要是灼烫烧伤和机械伤害,分别为工伤事故总数的35.8%、28.5%。③工伤伤害性质以骨折多见,约为总数的56.1%。④受伤工人的年龄分布以30~40岁段为主,约为总数的31.1%。⑤工伤事故原因中注意力不集中和违反操作规程分别为总数的43.0%,38.3%。结论12根据上述流行病学特点,采取相应的措施来减少工伤事故的发生。  相似文献   
25.
探讨胆囊结石化学类型与各影像学特征的关系,并建立简便而有效的体外预测结石化学类型的方法。  相似文献   
26.
生脉散多糖的组成及其初级结构分析   总被引:9,自引:0,他引:9       下载免费PDF全文
目的:研究复方中药制剂中多糖与单方多糖之间的组成关系,以及生脉散多糖的初级结构分析。方法:提取和精制了生脉散(SMS)单方药材红参、麦冬、五味子中多糖成分;然后采用Sephadex G-75柱层析分离纯化SMS多糖,得一浅黄色SMS多糖纯品,经紫外光谱、Sephadex G-200凝胶柱层析和琼脂糖凝胶电泳检测证明为均一组分。同时采用Sephadex G-200凝胶柱层析,测得SMS多糖组成。运用TLC法和HPLC法测定了SMS多糖纯品的单糖组成;并采用IR,高碘酸氧化和Smith降解推知其初级结构。结果:SMS多糖由红参多糖,麦冬多糖和五味子多糖所组成,其中含有葡萄糖、L-鼠李糖、D-木糖、D-果糖、半乳糖和乳糖等多种单糖,主要糖苷键为α-构型;多糖糖苷键以1→4连接键为主,1→3为次。结论:首次报道了生脉散多糖的组成及其初级结构分析。  相似文献   
27.
Foods have always been considered by man as a means of ensuring his physiological needs, allowing the growth, development and preservation of the body and its tissues (nutritional value of food). To this can be added the feelings of satisfaction and well-being that food gives to its consumer, thus constituting an element that is fundamental for our physiological and mental balance (the sensorial value of food).Nevertheless, recent scientific studies have shown that over and above the ensuring of nutritional needs, eating habits can also adjust certain functions of the human organism and thus play a beneficial or harmful role on one's health (the functional value of food).The whole concept of nutrition has been enriched by the notion that eating is not only a survival reflex (satisfaction derived through eating and the avoidance of harmful effects due to eating deficiencies or excesses): eating aims to improve one's health and well-being and to reduce the risk of developing various pathologies. These new data open interesting new horizons in today's context where health is increasingly expensive and people are increasingly concerned to improve their quality of live.  相似文献   
28.
摘要:目的:对民族药香青兰进行化学成分及药理活性的研究,对该药材的综合应用和深入研究奠定基础。方法:通过查阅1995-2022年知网、PubMed中的中英文文献与相关文献对香青兰进行综述。结果:经过系统的研究,发现香青兰的组成主要包含总黄酮和黄酮苷类、挥发油、三萜类和蛋白质等。这些成分有着多种药理作用,如抗缺氧、抗血栓和降血压。结论:香青兰对于治疗高血压,心脏病等有一定疗效。香青兰在蒙医临床中应用广泛。研究表明,香青兰的化学成分和药理作用已经取得了一定的进展,其作用范围广泛,对心血管疾病有显著的疗效。  相似文献   
29.
Male wild (Cavia aperea) and domestic (C. porcellus) guinea pigs were tested in two-bottle choice tests for preferences between glucose solutions of different concentrations and de-ionized water. Wild males showed significant preferences for concentrations between 0.025 and 0.4 M glucose while domestic males preferred only the 0.2 M glucose solution to de-ionized water. C. aperea males also consumed significantly greater volumes of liquid per kg body wt.34 during the glucose tests than did the C. porcellus males. These comparative results contrast sharply with those obtained by other authors with wild and domestic Norway rats.  相似文献   
30.
The feeding behavior of rats sympathectomized by neonatal administration of guanethidine (GUA) and/or adult adrenal demedullation (MDL) was investigated. GUA treatment tended to decrease body weight gain and food intake, chiefly by decreasing meal size and increasing satiety ratios. It also attenuated the increase in food intake caused by 2-deoxy-D-glucose (2DG; 150, 300, 450 mg/kg, IP) but not by insulin (3, 6, 9 U/kg, IP). MDL altered meal patterns in the same manner as GUA treatment but the effects were of smaller magnitude. It did not influence the response to either glucoprivic challenge. Combined GUA treatment and MDL generally produced additive effects. These results suggest that the major sympathetic influence on feeding is through adrenergic innervation and not circulating catecholamines. The hypothesis that the alteration in feeding patterns produced by ventromedial hypothalamic lesions is due to decreased sympathetic activity was not supported.  相似文献   
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