提高鱼苗成活率的技术措施

刚孵出的鱼苗称鱼花、水花、夏花,适应环境能力较差,个体较小,抗病能力较弱,如果管理不细,饲喂不当等均可引起死亡,导致成活率降低。因此,加强饲养管理,科学调节水质,有利于提高鱼苗的成活率,增加养鱼经济效益。1.整修鱼池鱼苗池宜选择背风向阳,水源供给方便、充足,水质良好,排     

提高鱼苗成活率的技术措施

从鱼苗放养前准备、放养注意事项以及放养后饲养管理3个方面对提高鱼苗成活率的技术进行总结,以期为提高鱼苗成活率、提高水产养殖效益提供指导。     

浅谈提高鱼苗成活率的关键措施

介绍了提高鱼苗成活率的关键措施,主要包括:清塘消毒、选择优质鱼苗、适时适温下塘、施肥、调节水质、巡塘防病等,为养鱼户提供参考。     

池塘鱼苗培育技术

池塘鱼苗培育包括鱼苗池的选择、清塘消毒、放养密度、饲养方法、日常管理等内容。文章详细介绍了池塘鱼苗的培育技术。     

鱼苗培育管理技巧

鱼苗培育是指将孵化出的鱼苗饲养成夏花的过程。它既是养鱼生产中的第一个环节，又是最重要、最难把握的一个环节。因为鱼苗细小幼嫩，活动力弱，摄食范围窄，对环境条件的变化十分敏感。要提高鱼苗成活率，培育出数量多、体质壮的夏花鱼苗，需把握以下技巧。     

一种生物量模型构建的新方法

以树木各分量生物量成比例为基础，利用树木各分量生物量之间存在相对生长关系，构建各分量生物量模型通式，采用模型评价指标，逐步剔除模型中参数变动系数大的变量，从而建立树木各分量生物量的最佳模型．     

马铃薯试管苗快繁中提高繁殖系数的方法

马铃薯脱毒试管苗的快速繁殖在马铃薯良种工厂化生产中应用广泛。如何在较短时间内提高苗的繁殖系数 ,降低生产成本 ,且生产出健壮的苗 ,是每一个生产性组培室应该考虑的问题。我们采取在培养瓶中留茬并补加液体培养基的方法 ,使每瓶母苗可重复利用 4～ 5次 ,在较短的时间内较大地提高了苗的繁殖系数。在相同时间内 ,把马铃薯试管苗的繁殖倍数由常规繁殖方法的 9倍提高到现在的 3 1 4倍。     

A new approach to the adoptive immunotherapy of cancer with tumor-infiltrating lymphocytes

The adoptive transfer of tumor-infiltrating lymphocytes (TIL) expanded in interleukin-2 (IL-2) to mice bearing micrometastases from various types of tumors showed that TIL are 50 to 100 times more effective in their therapeutic potency than are lymphokine-activated killer (LAK) cells. Therefore the use of TIL was explored for the treatment of mice with large pulmonary and hepatic metastatic tumors that do not respond to LAK cell therapy. Although treatment of animals with TIL alone or cyclophosphamide alone had little impact, these two modalities together mediated the elimination of large metastatic cancer deposits in the liver and lung. The combination of TIL and cyclophosphamide was further potentiated by the simultaneous administration of IL-2. With the combination of cyclophosphamide, TIL, and IL-2, 100% of mice (n = 12) bearing the MC-38 colon adenocarcinoma were cured of advanced hepatic metastases, and up to 50% of mice were cured of advanced pulmonary metastases. Techniques have been developed to isolate TIL from human tumors. These experiments provide a rationale for the use of TIL in the treatment of humans with advanced cancer.     

提高植物生理实验课教学质量的一些探索

针对农业院校植物生理实验课所存在的问题进行了改革探索 ,提高了学生能力和教学质量。     

A new approach to the oral administration of insulin and other peptide drugs

The oral administration of peptide drugs is well known to be precluded by their digestion in the stomach and small intestine. As a new approach to oral delivery, peptide drugs were coated with polymers cross-linked with azoaromatic groups to form an impervious film to protect orally administered drugs from digestion in the stomach and small intestine. When the azopolymer-coated drug reached the large intestine, the indigenous microflora reduced the azo bonds, broke the cross-links, and degraded the polymer film, thereby releasing the drug into the lumen of the colon for local action or for absorption. The ability of the azopolymer coating to protect and deliver orally administered peptide drugs was demonstrated in rats with the peptide hormones vasopressin and insulin.     

A new vision-based approach to differential spraying in precision agriculture

One of the objectives of precision agriculture is to minimize the volume of herbicides by using site-specific weed management systems. To reach this goal, two major factors need to be considered: (1) the similarity of spectral signatures, shapes, and textures between weeds and crops and (2) irregular distribution of weeds within the crop. This paper outlines an automatic computer vision method for detecting Avena sterilis, a noxious weed growing in cereal crops, and differential spraying to control the weed. The proposed method determines the quantity and distribution of weeds in the crop fields and applies a decision-making strategy for selective spraying, which forms the main focus of the paper. The method consists of two stages: image segmentation and decision-making. The image segmentation process extracts cells from the image as the low-level units. The quantity and distribution of weeds in the cell are mapped as area and structural based attributes, respectively. From these attributes, a multicriteria decision-making approach under a fuzzy context allows us to decide whether any given cell needs to be sprayed. The method was compared with other existing strategies.