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71.
中草药在鸡胚成纤维细胞(CEF)上对新城疫病毒的作用研究   总被引:2,自引:0,他引:2  
分离并培养鸡胚成纤维细胞(CEF),并感染新城疫病毒(NDV),通过观察细胞病变,检测在CEF上,复方中草药对NDV的影响。结果表明,中草药对新城疫病毒的中和、预防、治疗作用的最小抗病毒浓度分别是0.061mg/ml、0.244mg/ml、0.976mg/ml。  相似文献   
72.
湘黄鸡进行专业户(场)散养时,由于生产方式不同于舍饲群养,其生产环境、食物结构和易感病种类都必然发生变化。对此,笔者结合临床所遇病例进行了研究总结,对散养湘黄鸡的几种常发病的病因、病理、临床表现及防治特点等方面进行了介绍。  相似文献   
73.
为探明不同作物与娃娃菜轮作后的效果,在宁夏南部山区进行定位试验,采用高通量测序技术,结合土壤理化性质及酶活性,比较分析了娃娃菜-西兰花(CMB)、娃娃菜-大葱(CMG)、娃娃菜-洋葱(CMO)、娃娃菜-土豆(CMP)和以娃娃菜连作(CCC)为对照的5个处理的微生物多样性,旨在筛选出适宜与娃娃菜轮作的作物,为从栽培模式选择角度缓解或避免娃娃菜连作障碍提供理论依据。试验结果表明:与连作相比,轮作马铃薯土壤硝态氮含量最高为12.8 mg·kg-1,轮作大葱土壤速效磷含量最高为75.74 mg·kg-1,但不同轮作模式下速效钾和有机质含量有所下降。轮作马铃薯土壤的碱性磷酸酶、蔗糖酶与轮作洋葱土壤的过氧化氢酶、脲酶显著低于娃娃菜连作和轮作其他作物。细菌丰度在属水平上的结果表明轮作导致大部分有益细菌属丰度升高,如贪铜菌属(Cupriavidus)、鞘脂单胞菌属(Sphingomonas)、柄杆菌属(Caulobacter)等,有害菌及其他部分未分类功能作用菌属丰度降低,如伯克氏菌(Burkholderiaceae)、黄杆菌属(Flavobacterium...  相似文献   
74.
In ovo injection (IOI) of Naringin (N), flavanone was examined on post‐hatch blood biochemical parameters, antioxidant status and bone characteristics. Fertile eggs (n = 700) were distributed in seven groups with 100 eggs. On 14th and 17.5th days of incubation, four groups were injected using 15 or 30 mg active ingredient levels of naringin/0.5 ml saline/egg, low and high level, into amnion sac. Controls include sham (injected normal saline, 0.5 ml/egg on day 14 and 17.5th) and un‐injected group. IOI of high naringin and saline on 14th day of incubation resulted in lower hatchability and then higher mortality in last week of embryonic life. On day hatch, high levels of injected groups more body weight compared to the control. Chick length was increased at high levels of naringin on day 17.5th compared to control and saline injected. Quality traits of bones were improved in naringin‐injected groups compared to control. IOI of naringin influenced thyroid hormones on 14th day of incubation. Naringin groups influenced the Alkaline phosphatase (ALP), Calcium (Ca), superoxide dismutase (SOD), blood biochemical and lipids. Totally, amniotic IOI of naringin in last days of developing embryo may be useful for hatched chick, development of leg long bone or effect on biochemical metabolites by levels of flavanone that it needs more research.  相似文献   
75.
在基础日粮基础上,研究了色氨酸(Tryptophan,Trp)不同添加水平对7~8周龄AA公肉仔鸡血浆Trp浓度和平均日增重的影响.结果表明,在一定范围内,血浆游离Trp浓度和平均日增重均与日粮Trp水平至二次抛物线关系,其中血浆Trp浓度与日粮Trp水平是显著相关(P>0.05),而平均日增重不显著(P>0.05)。根据实验结果推荐,当日粮粗蛋白为18.77%时,7~8周龄公肉仔鸡日粮Trp的适宜水平为0.16%。  相似文献   
76.
To research on polysaccharides from Lagenaria siceraria (Molina) Standl.against Newcastle disease virus (NDV).Total polysaccharide and four different solvent extractions of Lagenaria siceraria (Molina) Standl.were extracted by the methods of hot water extraction and ethanol precipition in this study.The content of polysaccharide was measured by phenol-sulfuric acid method and infrared spectroscopy method.The safe concentration and growth of chick embryo fibroblast (CEF) were assayed by MTT method,in order to facilitated the comparison under the same level,the safe concentration was united as 78.125 μg/mL.Under the safety range of concentration,detected the block-virus activity,anti-virus activity and virus-killing activity of polysaccharides through the ways of pre-adding polysaccharides,post-adding polysaccharides and adding polysaccharides with NDV.The results showed that the direct inactivation and propagation inhibition activity of total polysaccharide and four different solvent extractions were stronger than anti-absorption function.Anti-virus inhibition rate of 70%,80% gradient alcohol precipitation of polysaccharides from Lagenaria siceraria (Molina) Standl.(LSP70,LSP80) and total polysaccharide (LSPt)were 40.41%,44.54% and 61.85%,virus-killing inhibition rate were 44.74%,58.76% and 59.38%.LSP80 had the highest virus inhibition rate as 37.14% in the block-virus activity of those five polysaccharides.In summary,70%,80% gradient alcohol precipitation and total polysaccharide in polysaccharides possessed better activity and would be as the materials for further research.  相似文献   
77.
中药成分对传染性法氏囊病毒感染细胞的影响   总被引:11,自引:0,他引:11  
将黄芪多糖、当归多糖、蜂胶多糖、淫羊藿多糖、板蓝根多糖、黄芪黄酮、蜂胶黄酮、淫羊藿黄酮、黄芪皂甙、人参皂甙等 1 0种中药成分与鸡传染性法氏囊病毒 (IBDV)以 3种顺序加入到培养 2 4h的鸡胚成纤维细胞 (CEF)中。即先加中药后接种病毒、先接种病毒后加中药、中药和病毒同时加入 ,观察细胞病变的程度 ,以评价它们对IBDV感染细胞的影响。结果表明 ,先加中药后接种病毒和中药与病毒同时加入时 ,多数中药成分处理组在病毒接种后 72h的细胞病变程度明显减轻 ,表明多数中药能抑制病毒感染细胞 ,且有一定的量效和时效关系。  相似文献   
78.
本实验以马立克氏病(MD)三价苗(SB_1+814+HVT)和HVT疫苗免疫1日龄肉用雏鸡,15日龄时腹腔注射马立克氏病强毒(vDMV)进行攻击,在攻毒后5、25、45和75天用间接ELISA法测定实验雏鸡血清、泪液、气管液、胆汁和肠液IgG、IgM和lgA含量的动态变化,结果发现免疫雏鸡强毒攻击后,其血清、泪液和气管液的IgG、lgM和IgA含量显著高于感染对照鸡,胆汁和肠液中IgA以及IgG、IgM显著高于感染对照鸡,其中三价菌免疫鸡的3种免疫球蛋白含量明显高于HVT免疫鸡;表明MD强毒攻击后,免疫雏鸡全身和消化道、呼吸道局部的体液免疫应答显著增强,三价苗免疫鸡的体液免疫反应明显高于HVT免疫鸡,并与其较高的免疫保护率相关。  相似文献   
79.
ABSTRACT

1. Over the past decade, rapid advancement in isolation methods for identifying markers of the once elusive intestinal stem cell (ISC) populations has laid the foundation for unravelling their complex interrelationships during homeostasis. Study on ISC in avian intestinal tissue might play a pivotal foundation for further studies on the epithelial-to-mesenchymal transition (EMT) in gastrointestinal disease and cell-based therapy as well as intestinal tissue engineering.

2. The following experiment isolated a population of fibroblast-like, plastic adhering cells derived from chick embryo intestine, showing a strong self-renewing and proliferative ability, which was maintained in vitro up to passage 25. The findings included growth characteristics, detected expression of cell surface markers and characterised the capability of these cells to differentiate towards the osteogenic, adipogenic, and chondrogenic cell lineages.

3. RT-PCR analysis showed that these cells from chick embryos expressed mesenchymal stromal cell markers CD44, CD90 and VIMENTIN as well as ISC-specific genes LGR5, MI1, SMOC2, BMI1, and HOPX. Immunofluorescence and flow cytometry confirmed this biology characterisation further.

4. In conclusion, cells were isolated from the intestine of 18-day-old chicken embryos that exhibited the biological characteristics of mesenchymal stromal cells as well as markers of intestinal stem cells. Our findings may provide a novel insight for in vitro cell culture and characteristics of ISCs in avian species, which may also indicate a benefit for obtaining cell source for intestinal tissue engineering as well as cell-based investigation for gastrointestinal disease and treatment.  相似文献   
80.
本试验以玉米沈农171×33O单交种及其亲本沈农171自交系为试材,通过1987~1988年的试验,测定了不同采收期玉米笋产量、质量、笋支长棍等指标。试验结果表明:单交种及自交系最佳采收期各不相同,沈农171×330单交种玉米笋最佳采收期为吐丝后第2天,沈农171自交系为吐丝后第1天。  相似文献   
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