应激损伤与影响应激的药物(综述)

过强的外界刺激对机体会造成损伤.如何对应激损伤进行预防?我们查阅了有关影响应激的药物文献资料,现予综述如下.1 应激对机体的损伤机体对外界刺激的应激主要是交感神经-肾上腺髓质系统和下丘脑-垂体-肾上腺皮质系统的变化.交感神经-肾上腺髓质系统兴奋,对有害刺激迅速发生反应,肾上腺素、去甲肾上腺素分泌增多,起着使机     

矽肺宁-锌提高机体对应激源适应能力的实验研究

本研究通过观察小鼠在缺氧、高温、低温条件下的死亡率,以及测定大鼠在绑缚条件下肾上腺内抗坏血酸含量等指标,探讨矽肺宁(一种治疗尘肺的中成药,X)、锌(Zn)、矽肺宁-锌联合应用(X-Zn)提高机体对应激源适应能力的作用,及其可能的作用机制.研究结果表明,X具有提高小鼠抗高温、低温二项作用;Zn具有提高小鼠抗缺氧、低温二项作用;而X-Zn联合应用具有提高小鼠抗缺氧、高温、低温三项作用,并且X-Zn提高小鼠抗缺氧的作用强于Zn.给X、Zn、X-Zn的大鼠经绑缚应激后,肾上腺内抗坏血酸含量比对照组低,提示在绑缚应激时,X、Zn、X-Zn能增强下丘脑-垂体-肾上腺皮质轴兴奋性.     

职业暴露和环境污染引起疾病的因果关系的判断:总体判断和个体判断

Demonstration of a causal relationship between chemical exposure and injury in litigation of toxic tort cases is a key to winning the case in Court. To evaluate whether a case has merit, two levels of causations,general causation and specific causation, are considered.““““ General causation““““ refers to the question, does exposure to the toxicant cause the type of injury.9 For example, does aluminum welding fume cause lung cancer.'? Bradford Hill' s nine criteria are used to analyze ““““general causation.““““ These criteria include strength of association, consistency, specificity, temporality, biological gradient, plausibility, coherence, experiment, and analogy. ““““Specific causation““““ refers to the question, did the Plaintiff's exposure to the toxicant cause the injury in this individual. For example, was Mr. Smith's lung cancer caused by his occupational exposure to aluminum welding fume.'? In court, the Judge and jury are asked to make a decision about specific causation, and award or deny damages accordingly. The expert witnesses testify as advisor to the court. As health consultants,we ask five questions to evaluate specific causation: 1 .Was the individual exposed to a toxicant, and if so,what was the dose (mute,concentration,duration,and frequency)?. 2.What is known about the toxicity of that chemical?. (e.g. ,What specific adverse effects have been associated with exposures to that toxicant.? How long does it take for symptoms to develop.'? What dose is required.'? The analyzing process of general causation is included in our question 2. ) 3. Did the symptoms claimed by this individual appear in a manner and time sequence that is consistent with what is known about the toxicity of the chemical.? 4. When exposure to the chemical ceased, did the symptoms get better or disappear in a manner and time sequence that is consistent with the known toxicology.'? 5. What other conditions or factors might have caused this symptom, and are they relevant to this case.'? By reviewing the available information relative to these five questions, the testifying expert helps the judge and jury decide whether the plaintiff's injury was, or was not caused by his exposure to a chemical toxicant.