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101.
ICGN is a partially inbred strain of mice with nephrotic syndrome caused by spontaneous glomerular lesion. It has been reported that the albuminuria in ICGN mouse was controlled by at least a single autosomal recessive gene (nep). In this study, we mapped the nep locus by linkage analysis of backcross progeny between ICGN and MSM mice using DNA pooling method. The linkage analysis revealed that the nep locus was localized on the distal part of chromosome 15.  相似文献   
102.
A common cellular sequence was independently transduced by avian carcinoma virus MH2 (v-mht) and murine sarcoma virus (MSV) 3611 (v-raf). Comparison of the nucleotide sequences of v-mht and v-raf revealed a region of homology that extends over 969 nucleotides. The homology between the corresponding amino acids was about 95 percent with only 19 of 323 amino acids being different. With this example, 5 of the 19 known different viral onc genes have been observed in viruses of different taxonomic groups. These data indicate that (i) the number of cellular proto-onc genes is limited because, like other viruses of different taxonomic groups, MH2 and MSV 3611 have transduced the same onc gene-specific sequences from different cell species and (ii) that specific deletion and linkage of the same proto-onc sequences to different viral vector elements affect the oncogenic potential of the resulting viruses. The difference in transformation capabilities of MH2 and MSV 3611 serves as an example.  相似文献   
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104.
Crop consumptive water requirement (Crop-ET) is a key variable for developing management plans to optimize the efficiency of water use for crop production particularly in semiarid zone. In Burkina Faso, the unfavorable climatic conditions characterized by the low and unevenly distribution of rainfall have pushed water resources management to the forefront of the crop production issue. Crop-ET is extremely required in rainwater effective management for mitigating the impact of water deficit on the crops. Basically, Crop-ET determination involves reference evapotranspiration (ETo) and crop coefficient (Kc) which required complete climatic data and specific site crop information, respectively. ETo estimation with the recommended FAO56 Penman–Monteith (PM) equation is limited in Burkina Faso due to the numerous meteorological data required which are not always available in many production sites. In such circumstances, research to compute directly Crop-ET as an alternative to the two-step approach of calculating ETo and determining site specific Kc, seems desirable. Therefore, this study aims to evaluate the performance of a mixture principal component analysis neural network (PCANN) model for computing rice Crop-ET directly from temperatures data in Fada N’Gourma region located in Eastern Burkina Faso, Africa. From the statistical results, rice Crop-ET can be successfully computed by using PCANN methodology, when only temperatures data are available in this African semiarid environment. Thus, in poor data situation, Crop-ET direct computation can be rapidly addressed through PCANN model for agricultural water management in African semiarid regions.  相似文献   
105.
The aim of this study is to assess the potential of the irrigation return-flow in a water reuse system, for the supply of other local water users. Both field survey and water-budget analysis were conducted, and the Chitong irrigation district in Taiwan was selected as the case study area. The results indicate that through the regulation of a pond with the effective capacity of 20,000 m3, a stable supply of 10,000 CMD of reuse water can be generated if the return-flow from the irrigation area of 200 hectares, which is about the size of a rotation plot, is intercepted. However, as the irrigation and effective rainfall are low from December to March, which are considered high risk for water supply, the irrigation return-flow decreases accordingly, and a series of responding measures are also suggested.  相似文献   
106.
This paper investigated the effect of three different treatments, namely: (i) sunlight (simulated by Xenon light) exposures, (ii) bleaching and (iii) perming on the damage of keratin fibre (with the use human hair). Four different testing methods were applied to quantify the hair damages. On evaluating the test results, it was concluded that the bleaching process imparted the most severe damaging action for hair. The results of the different test methods were evaluated and discussed.  相似文献   
107.
The nucleotide sequence of the genome of HTLV-III, the infectious agent etiologically associated with the acquired immune deficiency syndrome, predicts a small open reading frame, termed sor, located between the pol and env genes. A DNA segment containing 82 percent of the sor region was inserted into a prokaryotic expression vector, pJL6, to determine whether sor encodes a viral protein and to gain some insight into its possible function. The bacterially synthesized sor protein reacted with sera from individuals infected with HTLV-III, indicating that sor is expressed as a protein product or products that are immunogenic in vivo. Antibodies to the purified, bacterially synthesized sor protein were found to react specifically with the same protein and also with a protein of molecular weight 23,000 (23K) in HTLV-III-infected H9 cell extracts. The 23K protein comigrated with a protein immunoprecipitated by the serum of a hemophiliac patient with antibodies to HTLV-III, suggesting that this protein is probably the sor gene product.  相似文献   
108.
109.
采用变分方法考察了具有随机小费用的可修模型的维修策略问题,推导出了依赖年龄的最倨费用界维修策略所满足的微分方程及其边界条件。从而得到了费用界策略形式下的最优。对于包含预防性更换的可修模型也同样得到了费用界-预更换策略形式下的最优解。  相似文献   
110.
加工番茄果秧分离装置运动过程分析   总被引:4,自引:0,他引:4  
为了深入研究加工番茄果秧分离特性,分析了加工番茄果秧分离装置激振器的运动过程,利用达朗贝尔原理建立其理论模型。利用SolidWorks对激振器的运动过程进行了仿真,并在FS-35型加工番茄果秧分离试验台上,利用高速摄像机拍摄了分离滚筒的运动过程,利用Blaster’s Mas软件对录像进行了处理和分析。分析结果表明,理论模型与实际运动吻合较好,验证了理论模型的正确性。  相似文献   
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