Microchemical and surface evaluation of canine tibial plateau leveling osteotomy plates

OBJECTIVE: To determine the microchemical and surface composition of tibial plateau leveling osteotomy (TPLO) plates before and after explantation. SAMPLE POPULATION: 7 TPLO plates surgically removed from host dogs 6 to 54 months after implantation; 2 raw unpolished-and-unpassivated 316L TPLO plates; and 2 heat-treated, polished-and-passivated, and cleaned 316L TPLO plates. PROCEDURES: Samples were removed by use of standard techniques to ensure the plate surface was not damaged. Sample pieces were dissolved and analyzed by inductively coupled plasma-mass spectrometry (ICP-MS) to determine bulk elemental composition. Other sample pieces were investigated by use of scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and x-ray photoelectron spectroscopy (XPS) for determination of sample morphology, near-surface elemental composition, and surface elemental composition, respectively. To investigate the possibility of corrosion in situ, some samples were chemically corroded and analyzed. RESULTS: ICP-MS confirmed that elemental composition of samples was consistent with 316L stainless steel. The SEM and EDS analyses revealed trace amounts of polishing materials and a nonuniform carbonaceous biofilm on < 1% of the surface area of samples removed from the host dogs. The XPS analysis indicated an increase in the chromium-to-iron ratio on passivated surfaces, with no difference between passivated samples before implantation and after explantation. CONCLUSIONS AND CLINICAL RELEVANCE: Composition of the TPLO plates was consistent with 316L stainless steel. No chemical or topographic changes were detected in TPLO plates that had been implanted in dogs for up to 54 months. A small amount of biofilm was evident on the surface of 2 plates.     

兽药产品批准文号申报核发及管理有关问题探讨

兽药产品批准文号管理是我国控制兽药市场准入的前置性管理模式,本文就目前兽药产品批准文号申报、核发及管理中存在的一些问题进行了分析,对企业申报兽药产品批准文号时的注意事项进行了阐述。     

Features of accumulation,migration, and transformation of benzo[a]pyrene in soil-plant system in a model condition of soil contamination

Journal of Soils and Sediments - The investigation of accumulation, migration, and transformation features of benzo[a]pyrene (BaP) in a soil-plant system by using new ecologically friendly...     

Pyrogenic carbon quantity and quality unchanged after 55 years of organic matter depletion in a Chernozem

Chernozems typically have large stocks of organic carbon and of fire-derived, pyrogenic carbon (PyC). PyC had been considered to be slowly released but new results challenged this assumption, indicating that PyC can be lost within decades. We analyzed total soil organic carbon and PyC content (detectable as benzene polycarboxylic acids) in bulk samples, light and heavy fractions from a 55 year old bare fallow and a nearby steppe soil. Loss of PyC stock due to the long-term fallow management was much smaller (6%) than for soil organic carbon (33%), and we detected no changes in the degree of aromatic condensation of PyC. Most (70%) of the PyC was associated with the heavy fraction, and less with the light fraction (30%) pointing to organo-mineral interactions as important stabilizing processes.     

关于加强我国兽药监管体系建设的思考

《农产品质量安全法》的颁布和实施，标志着我国农产品质量安全监管工作进入新阶段，兽药作为保障动物性产品安全的农产品生产过程中的重要投入品，其监管工作尤其令人关注。作者曾在基层挂职从事兽药监管工作，对我国兽药监管体系建设，尤其是市县级兽药监管现状十分担忧。特撰文阐述了兽药及兽药监管工作的重要性，分析了目前我国兽药及监督管理体系现状、面临的任务及存在问题，指出了我国市县级兽药监管系统存在监管主体不明确、监管体系不健全、行政管理和执法能力较弱、经费保障机制不到位、队伍素质不高、宣传培训不够等问题，并对此提出了解决问题的建议与对策。各级农牧部门应借兽医管理体制改革的东风，加强监督管理体系建设，进一步加强兽药监督队伍建设，加大兽药监督工作的经费支持力度，切实加强兽药监督管理工作。[编者按]     

恩拉霉素的研究进展

概述了恩拉霉素的理化特性、药效学、毒理学和临床应用研究进展,展望了今后恩拉霉素的研究方向.     

部分国家和地区猪链球菌的耐药性及耐药机制研究进展

猪链球菌病作为一种具有重要公共卫生意义的疾病,其防治一直是人们关注的焦点。为了了解猪链球菌对于各种抗生素的耐药情况以及耐药机制的研究进展,作者查阅了相关资料,对部分国家和地区进行的相关研究进行综述,以期对耐药性和耐药机制的研究以及临床用药有所帮助。     

猪细小病毒基因组结构及检测技术研究进展

猪细小病毒是引起母猪繁殖障碍性疾病的主要病原体之一,对猪细小病毒的基因组、转录、编码的结构蛋白和非结构蛋白、转录的调控及血清学诊断、分子生物学检测技术方面的研究进展予以综述,以期对其进一步研究有参考价值。     

New alternative method of benzo[a]pyrene extractionfrom soils and its approbation in soil under technogenic pressure

Purpose

The optimization of benzo[a]pyrene extraction conditions by subcritical water extraction method from soils is the purpose of the research. The optimal conditions for benzo[a]pyrene recovery are 30-min extraction by water in a special steel cartridge at 250 °C and 100 atm.

Materials and methods

Studies were conducted on the soils of monitoring plots subjected to Novocherkassk Power Station emissions. Monitoring plots were established at different distances from the Novocherkassk Power Station (NPS; 1.0–20.0 km).

Results and discussion

It was shown that the use of water in subcritical state as a solvent for benzo[a]pyrene extraction from soil allows to avoid large volumes of organic solvents and to decrease the time of sample preparation. It is shown that the maximum benzo[a]pyrene maintenance was observed in soils of the monitoring plots located most close (to 5 km) to a pollution source in the area of the prevailing direction of a wind rose. Dynamics of pollutant accumulation in soils depend on number of Novocherkassk state district power station emissions.

Conclusions

The method of benzo[a]pyrene subcritical water extraction from soil was developed and approbated during long-term monitoring researches of technogenic polluted territories. The optimum conditions for benzo[a]pyrene extraction from soil have been determined: the soil is treating by subcritical water at 250 °C and 100 atm of pressure for 30 min. Trends in the accumulation of benzo[a]pyrene in soil zones of the thermal power plant influence have been researched over a 5-year period of monitoring observations by subcritical water extraction method. Benzo[a]pyrene accumulation in soils depends on the technogenic emissions to the atmosphere from Novocherkassk power station and on the soil physical and chemical properties.

     

我国兽用转基因微生物产品的安全评价

转基因生物是指通过基因操作技术对遗传物质（DNA）进行重组、修饰,从而改变基因组构成的动物、植物、微生物。动物用转基因微生物产品主要是指经过人工修饰基因的疫苗、诊断试剂和饲料添加微生物。转基因技术打破了异种微生物之间天然杂交的屏障,实现了微生物间的基因转移,获得了新的生物学性状。基因重组技术为人类有效的利用微生物的遗传特性,