我国规模化肉牛场牛病毒性腹泻-粘膜病流行状况监测

从山东、河南和河北省的６个规模化肉牛场随机采肉牛血清８９份，直肠粪拭子１６５份，分别用微量细胞中和试验和双抗体夹心ＥＬＩＳＡ试剂盒检测牛病毒性腹泻粘膜病（ＢＶＤＭＤ）的抗体和抗原。诊断结果：ＢＶＤＭＤ中和抗体阳性率为４６．２％～６５．０％；ＢＶＤＭＤ病毒抗原阳性检出率为５．１％～７７．２％。从而证实我国中原地区肉牛群中存在有ＢＶＤＭＤ。     

尸体脏器中激素含量与死亡时间的关系

目的探讨死亡后脏器中激素含量变化与死亡时间的关系.方法在动物死亡后不同时间内称取肝脏、脾脏组织采用放射免疫的方法,对内皮素、血栓素、皮质醇含量进行了测定。结果动物死亡后3h、6h、24h、36h、72h,内皮素和血栓素含量比0h显著降低(P<0.001);皮质醇含量在死后3h、6h逐渐降低,24h明显升高,尔后降低,变化也呈现一定的趋势。结论死亡后脏器中激素含量随死亡时间的延长而降低。     

Developmental Markers in Adolescence: Implications for Studies of Pubertal Processes

There is inconsistency in the outcome measures of biological and psychosocial studies using measures of puberty as a predictor. For example, some studies show that maturational timing may have differential influences (positive, negative, or no effect) depending on the specific disorder, dimension of measure, and gender. Other studies have suggested that some effects may be more directly linked to pubertal stage or hormone concentrations rather than timing per se. This study outlines several conceptual and methodological issues that may be relevant to addressing these inconsistencies, in the context of examining data from a study of maturational hormones obtained from a unique longitudinal cohort of 24 girls (age 10.0 ± 1.6 years) and 36 boys (age 10.4 ± 1.6 years) in the early part of puberty, where the developmental trajectory of these hormones were tracked annually in 65% of the sample. We explored the contributions of measures of pubertal growth and sociodemographic factors on hormone concentrations. In brief, it appears that no single measure best captures the maturational processes during puberty and suggests that multiple processes are occurring in parallel. Several conceptual and methodological implications are discussed that may guide investigators in interpreting existing studies of pubertal timing and behavior as well as in conducting future studies.     

应用Dot-ELISA检测牛胴体沙门菌

应用Dot ELISA法对西宁市某屠宰点 71份牛胴体淋巴结进行了沙门菌检测 ,同时与常规分离培养鉴定技术比较。结果 ,在 71份牛胴体样本中 ,用Dot ELISA法检出沙门菌阳性 33份 ,阳性率为 4 6 .4 8% (33/71) ;而用常规分离培养鉴定技术检出沙门菌阳性 31份 ,阳性率为 4 3.6 6 %(31/71) ;2种方法的阳性符合率为 81.82 % ,阳性检出率差异不显著 (P >0 .0 5 )。     

Scientific Uncertainty and Science-Based Precaution

The debate between advocates of the "Precautionary Principle" and those of "science-based regulation" hinges in large part on the standard of proof to be applied to the scientific evidence that a given action poses a danger of serious and irreversible environmental harm. We propose an intermediate approach, which we term "science-based precaution," intended to facilitate adaptive management of environmental issues – that is, learning through experience and experimentation.We propose that evidence justifying precautionary action must be sufficient to create a "reasonable belief" of serious and irreversible environmental danger. In other cases, in which the proponents of an action bear the burden of proof that the actions they propose will not cause environmental harm, we propose that they must make a "clear showing"to that effect. Both of these standards of proof are derived from a scale constructed from the standards of proof used in various branches of US law.The "reasonableness" standard of proof for the application of the Precautionary Principle is more cautious than the record of international efforts to protect the stratospheric ozone layer and to deal with climate change. It is analogous to the standard of proof imposed by US administrative law, and is also consistent with the position of the European Union and the holdings of the WTO Dispute Settlement Body in the beef hormones case. We further propose a Reasonableness Principle: that scientific research and technological innovations promising major benefits not be unreasonably blocked before their full implications are understood.