农民收入构成变化特点与分析评价

近年来,农民收入增长缓慢已成为农业和农村经济发展中的突出问题,分析评价农民收入构成变化情况与特点,利于探索农民增收的新途径和对策措施.……     

Characterization of monoclonal antibodies directed against swine leukocytes

Hybridomas were produced from fusions of the SP2/0 mouse myeloma with splenic cells from: 1) an outbred Sprague Dawley rat immunized with swine peripheral blood mononuclear (PBM) cells; 2) a (CBA/NDub X BALB/c Dub) F1 mouse immunized with concanavalin A (Con A) activated swine PBM cells and 3) a (BALB/c Dub X C3H/He Dub) F1 mouse immunized with swine thymocytes. The resulting supernatants were screened by a microcytotoxicity assay for activity against swine PBM cells. Four hybridomas (MSA1, MSA2, MSA3 and MSA4) were selected, cloned and characterized by their cell reactivity and effect on mitogenic assays. MSA1 and MSA2 belong to the rat IgG2b subclass. MSA3 and MSA4 are of the mouse IgG2a subclass. These monoclonal antibodies reacted in the following manner: MSA1 with monocytes, granulocytes, red blood cells and bone marrow cells; MSA2 with subset of T cells; MSA3 with B cells and subsets of T cells and monocytes (class II molecule) and MSA4, a pan-T cell reagent (E-rosette receptor). The involvement of the various cell types reactive to the different monoclonal antibodies in the mitogenic response of swine PBM cells to Con A, phytohemagglutinin (PHA) or pokeweed mitogen (PWM) was investigated by cellular depletion with monoclonal antibody plus complement. Cellular depletion of PBM cells with the following monoclonal antibodies plus complement treatment resulted in: MSA1, almost total reduction in the mitogenic response to low doses of Con A or PWM; MSA2, partial reduction in the proliferative responses to any concentration of Con A, PHA or PWM; MSA3, partial reduction in proliferative responses to low concentrations of Con A or PWM and 4) MSA4, total elimination of any proliferative response to Con A, PHA or PWM.     

奶牛繁殖疾病的调控

本文综述了奶牛繁殖疾病的发病原因和调控措施，分析认为奶牛的营养状况是影响奶牛繁殖力的重要因素。理想的奶牛管理应做到整个泌乳期始终监测奶牛的体况和奶牛日粮中微量元素的维生素的含量，避免营养素的不平衡而引发的奶牛繁殖障碍，同时应避免奶牛过肥或过瘦。适当补充某些维生素和矿物质十分重要。     

草鱼免疫防病技术操作方法

草鱼免疫保证有效抗原和防止抗原流失,是免疫成功的关键;组织免疫服务队伍是持久普及推广免疫防病技术的保证措施。     

浅谈农业科研与农业物流

农业科研在农业物流中的作用日趋明显，分析农业科研与农业物流的关系，提出农业科研在农业物流中的作用，并针对农业科研与农业物流的关系现状，提出协调农业科研与农业物流和谐发展的几条对策。