某鸡场鸡传染性法氏囊病弱毒疫苗饮水免疫后发生的一次鸡病的诊断

１９９１年４月上旬，四川某鸡场对３５７０只１３日龄依莎雏鸡作法氏囊病弱毒疫苗饮水免疫，１４日龄时发病死亡９只，到２３日龄９天内共死亡８１４只，病死率达２２．８％。对２０只送检病死鸡的沙门氏菌分离率为１／２０株（５％）．但病料人工感染小白鼠试验为阴性，证明非病原菌所致，用病料与新城疫血清（抑制价１：６４０）作用后接种非免疫健康鸡１组的存活率为７５％，直接接种未与新城疫血清作用病料的２组存活率为５０％，剖检回归本动物试验自然死亡和人为处死的病鸡发现了较为典型的法氏囊病变，由此认为：法氏囊弱毒疫苗饮水免疫是引起鸡群发病死亡的主要原因。     

工程机械油缸的可靠性分析计算

本文讨论装载机油缸的可靠性计算，用线性回归方法获取油缸的强度分布函数。用“应力－强度”干涉理论计算一定作业时间之后的可靠度，对影响油缸疲劳强度的因素进行了简单分析。     

《大学语文》教学的若干思考与实践

本文从长期的教学实践中，探索出在《大学语文》古代文学教学中，应贯穿以史带文，以文述史，以赏促读，读赏结合，文以载道，文道合一的原则。     

固定边界的制备型自由流动电泳分离蛋白质

本文研究并开发了一种固定边界的制备型自由流动电泳分离蛋白质的技术。以微孔滤膜作为液流的固定边界，在电场的作用下，根据蛋白质所带电荷的不同，可使目标蛋白或杂蛋白从一股液流电迁移至另一股液流。对该分离过程进行了理论分析，得出了以有效电泳迁移率为参数的数学模型。以牛血清白蛋白和牛血红蛋白为分离对象，确定了电场强度、蛋白质浓度和电泳时间等因素对分离过程的影响。     

一些化合物在钴60的γ射线辐照下的色变研究

用钴60的γ射线辐照了一批化合物样品,对这些样品在受辐照前后的颜色变化进行了观察研究,对显色样品颜色的热稳定性作了实验观测,还考察了一些样品的化学纯度对颜色变化的影响.     

Genetic mapping of chronic childhood-onset spinal muscular atrophy to chromosome 5q11.2-13.3

SPINAL muscular atrophy (SMA) describes a group of heritable degenerative diseases that selectively affect the alpha-motor neuron. Childhood-onset SMAs rank second in frequency to cystic fibrosis among autosomal recessive disorders, and are the leading cause of heritable infant mortality. Predictions that genetic heterogeneity underlies the differences between types of SMA, together with the aggressive nature of the most-severe infantile form, make linkage analysis of SMA potentially complex. We have now analysed 13 clinically heterogeneous SMA families. We find that 'chronic' childhood-onset SMA (including intermediate SMA or SMA type II, and Kugelberg-Welander or SMA type III) is genetically homogeneous, mapping to chromosomal region 5q11.2-13.3.     

Identification of a receptor for protein import into mitochondria

Anti-idiotypic antibodies, prepared using a chemically synthesized signal peptide of a mitochondrial precursor protein, recognized a mitochondrial integral membrane protein (p32). Fab fragments derived from both anti-idiotypic antibodies and monospecific antibodies against purified p32 inhibited protein import into mitochondria. Moreover, anti-p32 antibodies specifically immunoprecipitated a precursor-p32 complex after detergent solubilization of mitochondria. Immunoelectron microscopy and subfractionation of mitochondria indicate that p32 is located in contact sites between the outer and inner mitochondrial membranes.     

Partition of tRNA synthetases into two classes based on mutually exclusive sets of sequence motifs

The aminoacyl-transfer RNA synthetases (aaRS) catalyse the attachment of an amino acid to its cognate transfer RNA molecule in a highly specific two-step reaction. These proteins differ widely in size and oligomeric state, and have limited sequence homology. Out of the 18 known aaRS, only 9 referred to as class I synthetases (GlnRS, TyrRS, MetRS, GluRS, ArgRS, ValRS, IleRS, LeuRS, TrpRS), display two short common consensus sequences ('HIGH' and 'KMSKS') which indicate, as observed in three crystal structures, the presence of a structural domain (the Rossman fold) that binds ATP. We report here the sequence of Escherichia coli ProRS, a dimer of relative molecular mass 127,402, which is homologous to both ThrRS and SerRS. These three latter aaRS share three new sequence motifs with AspRS, AsnRS, LysRS, HisRS and the beta subunit of PheRS. These three motifs (motifs 1, 2 and 3), in a search through the entire data bank, proved to be specific for this set of aaRS (referred to as class II). Class II may also contain AlaRS and GlyRS, because these sequences have a typical motif 3. Surprisingly, this partition of aaRS in two classes is found to be strongly correlated on the functional level with the acylation occurring either on the 2' OH (class I) or 3' OH (class II) of the ribose of the last nucleotide of tRNA.