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871.
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应用在鸭胚成纤维细胞上连续传代的方法 ,获得了由雏鹅新型病毒性肠炎病毒强毒株(NGVEV CN株 )致弱的弱毒株 (CN4 0 株 )。该弱毒株TCID50 为 10 - 8.0 83,具有良好的安全性和稳定性 ,在易感 1日龄雏鹅连传 8代不返强。该弱毒具有良好的免疫原性 ,最小免疫剂量为 10 0 0 0TCID50 ,免疫后 3d产生部分免疫力 ,5d产生坚强免疫力。口服免疫效果最好 ,对雏鹅免疫期在30d以上。该弱毒株能够干扰强毒在雏鹅体内繁殖 ,进入鹅体后能够进行一定程度繁殖并排泄出体外 ,使同居雏鹅感染并获得一定程度免疫力。临床使用后可极显著降低雏鹅的死亡率。  相似文献   
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Gastromalacia is the acute autolytic erosion of the gastric wall. It generally occurs postmortem, and it appears as a slimy brownish black region of the wall which occurs principally in the gastric fundus. A 59‐year‐old woman died in the Emergency Department following a 2‐day period of mild abdominal pain, vomiting, and diarrhea. A forensic autopsy was performed which revealed a rupture of the gastric fundus that had caused leakage of gastric content into the abdominal cavity. There was no macroscopic evidence of peritonitis, and the stomach wall adjacent to the rupture site showed marked thinning. The gross appearance was typical of gastromalacia. In contrast, histological observations revealed the presence of an ulcer at the site of perforation and a severe acute inflammatory reaction indicating a robust reaction with an antemortem rupture.  相似文献   
877.
In further work investigating the intriguing application of diacetylene copolymers in fingermark detection, methods were developed to control (inhibit or enhance) the diacetylene polymerization reaction in fingermarks treated with a mixture of the monomers 2,4‐hexadiyne‐1,6‐bis‐(phenylurethane) (HDDPU) and 2,4‐hexadiyne‐1,6‐bis(p‐chlorophenylurethane) (HDDCPU) in acetone solution. These methods included the use of a humidity chamber to reduce the amount of background development while promoting development on the fingermark, subjecting developed fingermarks to freezing temperatures and using a solvent to remove unreacted monomer in order to inhibit the polymerization reaction. Developed fingermarks were enhanced by conventional lighting (white light, filtered light) and fast Raman mapping, which was shown to be advantageous over FTIR imaging. This study also demonstrated the applicability of diacetylene copolymer solutions in the covert detection of fingermarks on difficult surfaces. Furthermore, fingermarks were successfully developed with good ridge detail on pig skin (used as a model for human skin, a notoriously difficult surface on which to develop fingermarks).  相似文献   
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The EU has recently mooted the possibility of harmonising minimum penalties. ‘Minimum criminal penalties’ refers to the lowest sanction available for a judge in a concrete case. Calculating the actual penalty involves legal mechanisms that might mitigate that penalty. Comparative analysis reveals that a distinction needs to be made between minimum penalties included in national criminal codes (in abstracto penalty) and the lowest penalty that might be imposed (in concreto penalty). Although in abstracto minimum penalties are found in the criminal codes of most Member States, they are fiercely opposed in others. In concreto minimum penalties that constitute an absolute limit to the discretion of a judge are even more controversial. Against that background, this contribution reviews whether or not the EU should force the Member States to impose absolute, in concreto minimum criminal penalties. It examines the justifications presented in recent proposals in light of legal and criminological research.  相似文献   
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We contribute to the lack of tools to support efficient industrial policy-making, especially in the mineral beneficiation policy literature. To address this vacuum, we adapt the product space analysis approach to incorporate an input-output value chain lens. This framework is applied to the case of steel in South Africa to derive novel insights regarding the (in)efficiency of implementing a downstream linkage-based beneficiation policy. Our dynamic analysis approach allows for interactions with the rest of the product space. We find that a ‘leap-frogging’ approach to development within the value chain may be more optimal than a strict beneficiation based industrial policy.  相似文献   
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