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71.
阐述了蓝沙还原卡v9.2在保护电子阅览室计算机系统方面上的优势、工作原理、以及使用中常遇到的问题和解决方法。  相似文献   
72.
在草鱼免疫反应中莨菪佐剂性的初步观察   总被引:3,自引:0,他引:3  
在草鱼免疫反应中莨菪佐剂性的初步观察赵建培(福州市郊区水产技术推广站,福州350011)史维舟,陈昌福(华中农业大学水产学院,武昌430070)已有研究报道指出,英若具有增强鱼类免疫力的作用[1]。但是,关于度著究竟是如何作用于鱼类的免疫系统,即为什...  相似文献   
73.
This paper examines the effects of a single surface application of biosolids (at 20 dry Mg ha? 1) on plant species composition, forage quality and quantity, and C stocks after 14 yr of rest in rangelands of the Central Interior of British Columbia. More than two times the aboveground biomass of grasses and the percent cover of plant litter were found in the biosolids treatment relative to the control, along with reductions in bare soil and microbiotic crust cover. Significantly greater plant uptake of all macronutrients (C, N, P, K, S, Ca, and Mg); most micronutrients (B, Cu, Mn, Mo, and Zn); and Al occurred in the biosolids treatment. P and Cu were the only two nutrients to be more concentrated in the biosolids-treated forage relative to the control forage, while N, Mg, and protein were more concentrated in the control forage. No significant difference in forage digestibility was found between biosolids and control treatments. Bluebunch wheatgrass, the late-seral native grass species, had significantly increased cover and aboveground biomass in the biosolids treatment relative to the control; however, between 2006 and 2016, non-native Kentucky bluegrass had reached > 25% cover in the biosolids plots, perhaps restricting the full recovery of bluebunch wheatgrass. Our findings indicate that biosolids application to ungrazed rangeland can increase long-term forage production and reduce bare soil. However, at our study site biosolids application also led to a long-term shift in the plant community composition away from the late-seral (i.e., bluebunch wheatgrass) trajectory, and the effects of this shift on rangeland health and productivity require further investigation.  相似文献   
74.
以25个不同青贮玉米品种为试验材料,在宁夏银川北部盐碱地,通过测定不同品种大喇叭口期和成熟期的表型性状和光合气体交换参数进行耐盐碱性鉴定,并利用主成分分析和模糊隶属函数法对不同青贮玉米的耐盐碱强弱进行综合评价。结果表明:各青贮玉米品种处于不同生育期时对盐碱的敏感程度不同(发育阶段性),同一时期不同品种之间耐盐碱性也存在着差异(品种特异性)。根据综合评价值(D值)大小,将耐盐碱性分为三级:D值大于0.6为强耐盐碱性材料;D值在0.2~0.6之间为中耐盐碱性材料;D值低于0.2为对盐碱敏感的材料。其中,在大喇叭口期时具有强耐盐碱性的材料有:科多8号、桂青贮1号和133-2/1528,D值分别为0.770、0.705和0.614;在成熟期时具有强耐盐碱性的材料有:H14/A18和桂青贮1号,D值分别为0.761和0.728;而表现为敏盐性的材料为H14/1528,D值在大喇叭口期和成熟期时分别为0.140和0.155;其余品种均属于中度耐盐碱材料,D值处于0.2~0.6之间。  相似文献   
75.
利杂犊牛小肠各段长度与黏膜结构的发育学变化   总被引:5,自引:0,他引:5  
利用图像分析法研究1月龄,4月龄和6月龄健康利杂犊牛小肠结构的发育形态变化。结果显示,犊牛小肠各段在不同的月龄,其长度变化差异显著(P<0.05);不同月龄犊牛的十二指肠、空肠、回肠的黏膜厚度、肌层厚度不同程度的增加且差异极显著(P<0.01);从1月龄至6月龄,十二指肠、回肠绒毛长度分别增加45.7%和8.0%;而空肠的绒毛以4月龄最长(392.48μm),绒毛高度/隐窝深度(V/C)值以4月龄的最大(2.63),且与1月龄和6月龄时比较差异极显著(P<0.01),但1月龄与6月龄相比较差异不显著(P>0.05)。结果提示,6月龄前犊牛小肠黏膜结构变化较大,犊牛断奶合理日龄应进一步研究。  相似文献   
76.
Oral squamous cell carcinoma (OSCC) is the most common oral epithelial malignancy in dogs. It exhibits locally aggressive biological behaviour with the potential to metastasize, and a reported 1-year survival rate of 0% when left untreated. Expression studies suggest that aberrant MAPK signalling plays a key role in canine OSCC tumorigenesis, which is consistent with BRAF and HRAS MAPK-activating mutations reported in some tumours. Several morphological subtypes of canine OSCC have been described, with papillary, conventional, and basaloid as the most common patterns. We hypothesized that mutational differences may underlie these phenotypic variations. In this study, targeted Sanger sequencing and restriction fragment length polymorphism assays demonstrate that up to 85.7% of canine papillary OSCC (n = 14) harbour a BRAF p.V595E mutation. Assessment of neoplastic epithelial cell proliferation using Ki67 immunolabelling (n = 10) confirmed a relatively high proliferation activity, consistent with their known aggressive clinical behaviour. These findings underscore a consistent genetic feature of canine papillary OSCC and provide a basis for the development of novel diagnostic and targeted therapeutic approaches that can improve the quality of veterinary care.  相似文献   
77.
采用Annexin V-FITC/PI双染色法,用流式细胞仪检测了猪繁殖与呼吸综合征病毒(PRRSV)实验感染SPF猪不同时期外周血单核细胞和肺泡巨噬细胞感染Annexin V-FITC^+/PI^-细胞群(早期凋亡细胞群)。结果显示,PRRSV感染猪外周血单核细胞和肺泡巨噬细胞Annexin V-FITC^+/PI^-细胞群的表达率均明显高于正常对照猪,感染后24h表达率达最高值。  相似文献   
78.
大豆活性肽对肉鸡肠道黏膜结构的影响   总被引:4,自引:0,他引:4  
将500只1日龄艾维茵肉鸡随机分为5组,即分别饲喂添加80、120和200g/kg大豆活性肽的日粮、添加抗生素的日粮和基础日粮。在28、49日龄取材,采用组织切片及组织化学染色方法检测肉鸡十二指肠、空肠、盲肠的绒毛长度与隐窝深度比值、杯状细胞数量,观察大豆活性肽对肉鸡肠道黏膜结构的影响,进而研究大豆活性肽对肉鸡消化能力的作用。结果表明:日粮中添加80 ̄120g/kg的大豆活性肽能够提高肉鸡生长初期的肠道杯状细胞数量,增加肉鸡肠道绒毛长度/隐窝深度比值。  相似文献   
79.
为了建立稳定转化家蚕细胞持续表达外源基因的技术体系,构建了基于piggyBac转座子的带有人粒细胞-巨噬细胞集落刺激因子基因(hGM-CSF)和新霉素抗性基因(neo)表达元件的转基因载体pigA3GFP-IE-neo-FH-hGM-CSF-polyA-fib-L-intron1,以及带有hGM-CSF和吉欧霉素(zeocin)抗性基因的昆虫细胞转化载体pIZT-IE-hGM-CSF,分别转染家蚕卵巢BmN细胞,并以含相应抗生素G418或zeocin的培养液筛选,得到稳定的转化细胞系FH-hGM-CSF和IE-hGM-CSF。ELISA检测结果显示,hGM-CSF在FH-hGM-CSF和IE-hGM-CSF转化细胞系的表达水平分别为1.534 55 fg/个细胞和2.227 38 fg/个细胞。  相似文献   
80.
In studies to identify genotypes resistant to infection with citrus viroids, Eremocitrus glauca and Microcitrus australis were selected because their evolution in their habitat in Australia and New Guinea may have led to the selection of unusual traits. The movement and accumulation of Citrus exocortis viroid (CEVd), Hop stunt viroid, Citrus bent leaf viroid, Citrus dwarfing viroid, Citrus bark cracking viroid and Citrus viroid V (CVd‐V) in self‐rooted as well as in graft‐ propagated E. glauca and M. australis plants was assessed by northern hybridization, RT‐PCR and by topworking to the sensitive selection 861‐S1 of Etrog citron. In both plant species the inoculated viroids were undetectable unless these plants were grafted to a susceptible Citrus partner, the rough lemon rootstock and/or the topworked Etrog citron, which acted as viroid sources. The results obtained indicate that M. australis and in particular E. glauca are poor viroid hosts in which viroid replication/accumulation does not occur or is extremely inefficient. However, viroid downward and upward movement to grafted Citrus partners in which viroid replication and accumulation occurs efficiently was not impaired. Eremocitrus glauca and M. australis showed differences regarding their properties as viroid hosts, but for both species CEVd seemed to have the lowest affinity among the viroid species tested and CVd‐V the highest. Even though E. glauca and M. australis do not appear to be truly resistant to viroid infection, they are interesting genotypes for further characterization of the mechanisms involved in viroid infection.  相似文献   
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