大鼠海马三维结构及学习记忆能力在连续缺碘子代的表现

用低碘饲料复制了连续多代的大鼠克汀病模型，研究了第１代和第２代子鼠的学习记忆能力和重建的海马三维结构。结果表明，与正常组大鼠比较，克汀病子鼠生长发育迟缓，甲状腺呈增生性甲状腺肿病变，其血清甲状腺激素水平降低，逃避防御条件反射显示学习记忆能力低下等。以上病在第二代克汀鼠明显重于第一代。海马结构损害是克汀病大鼠学习记忆能力低下的形态学基础。     

带有分子轨道能量的3D-QSAR对N-氨基咪唑的研

N-氨基咪唑(NAIMs)能通过三种不同的作用方式抑制HIV-1的复制. 用比较分子场（CoMFA）方法对一系列有共同骨架的NAIM分子建立3D-QSAR模型. 与以往模型不同的是，在偏最小二乘（PLS）分析中尝试引入分子轨道能量的信息来研究生物活性与分子轨道能量的关系. 结果得到了几个模型，分子轨道能量对模型的贡献能为21.7%，轨道HOMO5对模型的贡献最大.     

HCV复制抑制剂的定量构效关系的研究

选用60个结构多样的HCV复制抑制剂分子作为数据集,随机选择其中46个分子作为训练集,剩余14个分子作为验证集.采用多元线性回归(MLR)和主成分分析(PCA)方法对每个分子的646个理化和结构参数进行了线性回归分析,并分别建立各自的最优模型.结果表明MLR中的逐步和向前法所建模型最佳,模型结果为:训练集R2=0.827,验证集R2=0.850,模型能够直观地反映影响化合物活性的主要因素.该模型将有助于筛选和开发新的HCV复制抑制.     

赤麂染色体复制的研究

本文应用细胞融合技术,姐妹染色单体分化染色法和我们提出的可以同时显示核仁组织者与姐妹染色单体分化的银染色方法,在赤麂染色体上进行了研究。在中期染色体和间期细胞各时期的期前凝聚染色体上,看到了分化染色的姐妹染色单体。银染色法表明,在深染的姐妹染色单体上,核仁组织者区银染色为阳性,浅染的染色单体上是阴性。姐妹染色单体分化染色和核仁组织者的银染色指出,中期染色体和间期细胞期前凝聚染色体的结构是相同的。赤麂的染色体复制符合于DNA半保留复制模型。rDNA的复制也具有半保留复制的特性。     

分子信标用于核酸连续复制过程的体外实时监测

利用分子信标核酸探针实时监测了核酸连续复制过程. 分子信标不仅作为模板参与复制反应, 而且同步将复制过程的信息转换为荧光信号, 实现复制过程的体外实时监测. 该方法不仅为DNA复制检测提供了一种实时研究手段, 而且为核酸复制动力学及与复制相关疾病的深入研究提供了一种新的思路.     

饲料添加剂中铜和锰的原子吸收光谱直接测定方法

报道了用次灵敏线原子吸收光谱法直接测定饲料添加剂（预混料）中高含量铜、锰的分析方法；解决了以往高铜、锰预混合饲料测定中，由于称样量小，稀释倍数过大所引起的分析误差；方法简便、快速、实用性强，已广泛应用于实际饲料预混料样品的分析，获得满意结果。     

紫外吸收光谱结合化学计量学测定饲料中三聚氰胺的含量

饲料经过酸-硅胶沉淀除去基质,测定所得上清液的紫外吸收光谱。采用偏最小二乘法(PLS)、人工神经网络(ANN)、支持向量回归法(SVR)三种化学计量学方法建立紫外吸收光谱对三聚氰胺浓度的预测模型。结果:PLS模型的R2为0.9926~0.9940,均方根差为0.2346~0.2612;ANN模型的R2为0.9999,均方根差为0.0265~0.0408;SVR模型的R2为0.9997~0.9999,均方根差为0.0010~0.0024。SVR模型的预测效果最好。研究表明,紫外吸收光谱-化学计量学建模用于快速、准确测定饲料中三聚氰胺是可行的,且设备要求低、操作简单,有望推广使用。     

农业部饲料质量检测昆明中心建成

由农业部、国家认监委组成的审查认可和计量认证专家评审组对农业部饲料质量监督检测（昆明）中心进行了审查认可和国家计量认证，中心一次性通过审查认可和计量认证。至此，该中心已成为全国第10家农业部饲料质量监督检测中心。昆明中心具备了按相关标准对饲料用鱼粉等115个产品、饲料中盐酸克仑特罗等115个参数进行检验的能力，可承担饲料常规、微量元素、黄曲霉毒素、细菌、霉菌总数等指标的检测。     

超分子模板法合成具有复杂形态的无机材料

具有复杂形态的无机材料可以通过超分子模板的形态花样复制制备出来。本文从基本概念，制备方法，合成机理，生物模拟实质和潜在应用前景等方面综述了这些新的合成策略和材料的研究进展。     

新方法快速精确检测饲料中叶酸

正北京市饲料监察所制定起草的行业标准《饲料中叶酸的测定高效液相色谱法》通过验收。叶酸在现代饲料工业中是一种常用、保障动物健康和良好生产性能的饲料添加剂。本次验收通过的标准方法灵敏度高、适用范围广、操作简单。此项成果填补了国际上关于饲料中叶酸检测方法标准     

近红外反射光谱技术在动物营养研究中的应用进展

介绍了近红外反射光谱(NIRS)技术的基本原理,着重评述了其在动物营养研究中的评价动物饲料及日粮的营养价值、估测动物采食量及消化性能、估测动物的营养健康状况等方面的应用进展(引用文献37篇)。     

Determination of metal concentration in fat supplements for swine nutrition by atomic absorption spectroscopy

The presence of some essential and toxic metals in fat supplements for swine diet was investigated. Collected samples represented a relevant production of the Italian industry. In particular, some samples were enriched with antioxidants or waste cooking oils. The method for the determination of Ca, Cu, Cd, Fe, Mg, Mn, Ni, Pb, and Zn in fat samples was developed by means of a certified reference material (CRM 186) and a representative fatty sample (RFS). All samples were digested in closed vessels in a microwave oven and then analyzed by flame atomic absorption or graphite furnace atomic absorption spectrometry. The entire analytical method provided a satisfactory repeatability and reproducibility confirmed by agreement between the experimental recovery data obtained for the CRM 186 sample and, with the method of standard additions, for the RFS material. The samples generally showed a small amount of metals compared with the recommended daily intake for the essential elements. On the other hand, some samples contained a significant concentration, from an analytical point of view, of Cd, Ni, and Pb. Principal component analysis (PCA) was applied to inspect the experimental data obtained from samples analysis. Basically no differences were detected in terms of metal concentration among the fat supplements analyzed.     

淀粉微球形成过程的介观模拟及实验

以环己烷为油相、淀粉乳液为水相、Span60和Tween60为乳化剂,对淀粉微球的形成过程进行了耗散粒子动力学(DPD)模拟及实验研究.模拟结果表明,淀粉微球的形成过程存在四个阶段,即淀粉与乳化剂分子无规则分散阶段、小聚集体形成阶段、球状聚集体形成阶段和稳定平衡阶段,并且发现油水比是影响聚集体是否能形成球状的关键因素.油水比小于7的条件下,油水两相分离较难,水相呈现片状、十字型状、柱状及椭球状等形状;当油水比增加到8,水相能形成微球且微球粒径随油水比增加而减小.同时实验结果表明,油水比为8时,微球粘连,几乎看不清球状形貌,油水比为10～20时,微球的粒径随油水比的增大而减小.实验结果很好地吻合了模拟结果.     

广东某高校学生膳食硒摄入状况

为了解广东大学生膳食硒的摄入状况,进而了解广州市居民的膳食硒摄入状况,采用单纯随机抽样的方法随机选取广东某高校某班学生10人,男女生各半,用双份饭法收集这10名学生连续7d内每天摄入的全部食物（包括饮水、饮料、零食等）,共70份样品,用荧光分光光度法测定了各样品的硒含量,得到学生在调查期间膳食硒的摄入状况。结果表明,男、女生人均膳食硒摄人量分别为86．51μg／d和69．92μg／d,学生总体人均膳食硒摄入量为78．22μg／d。该校学生膳食硒的摄入量达到了中国营养学会推荐的参考摄入量（50—250μg／d）的要求。     

Effect of age and food intake on dietary carbon turnover recorded in sheep wool

We present the results of a series of controlled feeding experiments with sheep, designed to investigate the effects of age and level of food intake on the kinetics of incorporation of the dietary carbon signal into wool. Four different groups of three sheep each, ranging in age from 6 to 78 months, were fed a C(3) diet and switched to a C(4) diet for up to 250 days. Different quantities of the same C(4) diet were provided to each group, in order to achieve different growth rates (high, low, and no growth). Wool was repeatedly shorn from each animal and processed for delta(13)C analyses. Results show that newly grown wool does not start recording the isotope composition of the new diet immediately after the diet-switch. The time-lag varies according to the age of the animal, from 6 +/- 1 days in lambs to up to 15 +/- 4 days in the older ewes. Wool from fast-growing lambs approached equilibrium faster than that from slow-growing lambs and young ewes, with old ewes being the slowest. However, 3 weeks after the diet-switch, the differences in wool delta(13)C values between the four different groups of animals were relatively small and represented less than 15% of the isotopic difference between the two diets. These results suggest that a single equation can be used to reconstruct previous diets for animals of different age, provided that the diet is similar and all individuals are in positive protein balance.     

苦荞粉提取液中黄酮类化合物含量测定方法的选择

通过硼酸-柠檬酸法、硝酸铝-亚硝酸钠-氢氧化钠法、氯化铝-乙酸钠法及芦丁法测定苦养粉中黄酮类化合物含量的比较，试验结果表明，芦丁法仅可测定苦荞提取液中部分黄酮类化合物的含量，而氯化铝法和硼酸-柠檬酸法无法将黄酮类化合物全部络合，试验选择硝酸铝法作为苦荞粉中黄酮类化合物的含量测定方法。     

The Applicability of Essential Oils in Different Stages of Production of Animal-Based Foods

Essential oils (EOs) have been used for centuries, and interest in these compounds has been revived in recent years. Due to their unique chemical composition as well as antimicrobial, immunostimulatory, anti-inflammatory and antioxidant properties, EOs are used in pharmacology, cosmetology and, increasingly, in animal breeding and rearing, and processing of animal raw materials. Essential oils have become a natural alternative to preservatives, taste enhancers and, most importantly, antibiotics, because the European Union banned the use of antibiotics in metaphylaxis in animal husbandry in 2006. In the animal production chain, EOs are used mainly as feed additives to improve feed palatability and increase feed intake, improve animal resistance and health status, and to prevent and treat diseases. Recent research indicates that EOs can also be applied to sanitize poultry houses, and they can be used as biopesticides in organic farming. Essential oils effectively preserve meat and milk and, consequently, improve the safety, hygiene and quality of animal-based foods. Novel technologies such as encapsulation may increase the bioavailability of EOs and their application in the production of food and feed additives.     

均衡膳食可使幼儿锌、铜、铁营养平衡研究

目的通过幼儿进食均衡膳食可使锌、铜、铁营养平衡,目的使幼儿健康成长。方法常规体检、原子吸收法血检3 000多幼儿,其中随机抽查300名幼儿作调查,进行均衡膳食前后的自身对比。结果幼儿进食均衡膳食后,每人每日锌、铜、铁摄入量达标,则血中锌、铜、铁含量达标;而进食均衡膳食前每人每日锌、铜、铁摄入量不达标,导致血中锌、铜、铁含量也不达标,则会影响幼儿生长发育和健康成长。结论建议在幼儿及学生中推广均衡膳食和开展营养工程,以保证其健康成长。     

Application of matrix solid-phase dispersion in the determination of dibenzo[a,l]pyrene content of experimental animal diets used in a large-scale tumor study.

A method utilizing matrix solid-phase dispersion (MSPD) was developed for isolation and determination of dibenzo[a,l]pyrene (DBP) in experimental rainbow-trout diets used in a large-scale carcinogenesis study. A 0.5 g sample of moist ration containing 0-225 ppm DBP (dry basis) was mixed with 2 g C18 sorbent and benzo[a]pyrene internal standard was added to the mixture. Extraction and clean-up were accomplished in a single step by extracting the sample mixture with hexane-benzene 4:1 from a cartridge containing 2 g Florisil. DBP was quantified by HPLC on a C5 bonded phase column with fluorescence detection. Mean analytical recovery of DBP from control diet spiked at three concentration levels was 101 to 107% with relative standard deviations of 1 to 7%. The limit of detection of DBP was equivalent to 0.014 ppm in the ration. Application of the method to verification of DBP levels in trout rations from the carcinogenesis study is described. Control ration (0 ppm DBP) was screened for possible DBP contamination and none was found. This is the first report on analysis of DBP in experimental animal diets.     

Determination of selenium daily intakes in two small groups of the Portuguese population by replicate sample neutron activation analysis

Selenium daily intake was determined for two small groups of the Portuguese population, based on the analysis of duplicate diet portions. The total amount of food ingested during a day was collected for 18 workers of the Technological and Nuclear Institute (ITN-Sacavém) and for 6 females of Reguengos de Monsaraz, a small town in the south-eastern hinterland. The average selenium daily intake was 43 ± 20 and 32 ± 13 μg per person, respectively, both lower than the Recommended Dietary Allowance (RDA) of 55 μg day⁻¹. Selenium in diet samples was determined by replicate sample neutron activation analysis (RSINAA). The method was considered accurate for the selenium determination.