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101.
禽畜粪便沼气发酵液的分离及肥料再利用研究   总被引:3,自引:0,他引:3  
用硫酸铁和饱和石灰水作为凝聚剂,对禽畜粪便经厌氧发酵制取沼气的残余物(发酵液)能进行效果较好的固液分离.分离所得残渣(沼渣),经适度烘干后与化肥配制成有机复混肥.用这一新型复混肥进行的辣椒盆栽试验结果表明,该肥料能增加辣椒苗期植物体对氮、磷、钾的吸收,提高肥料利用率.与化肥相比,等养分量沼渣有机复混肥增产9.5%~11.6%,80%养分量的沼渣有机复混肥增产14.5%~16.4%.有机复混肥还使辣椒Vc提高.  相似文献   
102.
Toll-like receptors (TLRs) participate in regulation of adaptive immune responses, and lymph nodes play key roles in the initiation of immune responses. There is a tolerance to the allogenic fetus during pregnancy, but it is unclear that expression of TLR signaling is in ovine lymph node during early pregnancy. In this study, lymph nodes were sampled from day 16 of nonpregnant ewes and days 13, 16, and 25 of pregnant ewes, and the expressions of TLR family (TLR2, TLR3, TLR4, TLR5 and TLR9), adaptor proteins, including myeloid differentiation primary-response protein 88 (MyD88), tumor necrosis factor receptor associated factor 6 (TRAF6), and interleukin-1-receptor-associated kinase 1 (IRAK1), were analyzed through real-time quantitative polymerase chain reaction, Western blot, and immunohistochemistry analysis. The results showed that mRNA and protein levels of TLR2, TLR3, TLR4, TRAF6, and MyD88 were upregulated in the maternal lymph node, but TLR5, TLR9, and IRAK1 were downregulated during early pregnancy. In addition, MyD88 protein was located in the subcapsular sinus and lymph sinuses. Therefore, it is suggested that early pregnancy induces changes in TLR signaling in maternal lymph node, which may be involved in regulation of maternal immune responses in sheep.  相似文献   
103.
It is known that the regional lymph node (RLN) may not correspond to the sentinel lymph node (SLN) (the first lymph node draining the tumour), and many diagnostic techniques have recently been aimed at its detection. Although lymphoscintigraphy is the gold standard in both human and veterinary medicine for SLN mapping, it is relatively unavailable in veterinary medicine due to costs and difficult management of the radiotracer. This prospective study evaluated, as a first aim, the feasibility and sensitivity of the computed tomography lymphography (CTL) in detecting the SLN in 62 mast cell tumours (MCTs). The second aim was to evaluate the accuracy of the CTL in identifying the most representative lymph node of the patient's lymphatic status; the histological status of the SNL was compared with that of the RLN, to see in how many cases the patient's stage would have changed according to the RLN. When the RLN turned out to be also the SLN it was decided to excise, as a control LN, the one localised in the neighbourhood of the MCT (neighbouring lymph node; NLN). The detection rate was 90%, with failure of SLN identification in six cases. In 18 (32%) of 56 MCTs with a diagnostic CTL, the SLN did not correspond to the RLN. Forty-five MCTs were surgically removed, together with their corresponding SLN and RLN/NLN. Since the clinical stage of the patient would have changed in only 7% of cases, CTL is a reliable method of detecting the SLN and, for staging purposes, there is no need to remove other LNs.  相似文献   
104.
以苯甲酸为催化剂,以三乙、硫脲、3-吡啶甲醛为原料制备了4-(3-吡啶基)-6-甲基-5-乙氧羰基嘧啶-2-硫酮(简称嘧啶硫酮),用1 H NMR表征其结构.采用失重法、Tafel极化法评价了嘧啶硫酮在1 mol/L HCl中对X70钢的缓蚀性能.结果表明,嘧啶硫酮在酸性环境中对X70钢的腐蚀具有较好的抑制作用,缓蚀率随温度的升高而降低,缓蚀率最大可达93.2%.在低温303K时,ΔG00,表明吸附过程是自发进行且符合Langmuir吸附等温式;ΔH00,说明嘧啶硫酮在吸附过程中放热,升高温度不利于吸附.并用SEM对X70钢表面型态做了表征.  相似文献   
105.
106.
Since the first publication on “regional ileitis”, the relevance of this chronic inflammatory disease condition termed finally as Crohn's disease is continuously increasing. Although we are beginning to comprehend certain aspects of its pathogenesis, many facets remain unexplored. Host's gut microbiota is involved in a wide range of physiological and pathological processes including immune system development, and pathogen regulation. Further, the microbiome is thought to play a key role in Crohn's disease. The presence of Crohn's-associated variants of NOD2 and ATG16L genes appears to be associated not only with alterations of mucosal barrier functions, and bacterial killing, but the gut microbiota, as well, reflecting a potential relationship between the host's genotype and intestinal dysbiosis, involved in disease etiology. This review aims to characterize some exciting new aspect of Crohn's disease pathology, focusing mainly on the role of intestinal microbes, and their interplay with the immune system of the host.  相似文献   
107.
将啤酒糟和麦芽根按不同比例袋装混贮,分别在30、60、90、120 d开袋取样进行感官评定,pH值、氨态氮、干物质、粗蛋白、中性洗涤纤维及有机酸含量分析。结果表明:混贮时间和水分含量均对混贮效果有显著影响;混贮饲料在混贮前60 d各指标变化范围较大,60 d后变化范围较小,并逐渐趋于稳定状态;混贮饲料以含水量50%的袋装混贮效果最好,其次是60%、40%,70%最差。  相似文献   
108.
Background: Plasma α‐melanocyte‐stimulating hormone (α‐MSH) and adrenocorticotropin (ACTH) concentrations in horses vary with season, confounding diagnostic testing for pituitary pars intermedia dysfunction (PPID). Hypothesis: The goals of this study were to determine whether seasonal variation in plasma α‐MSH and ACTH concentrations in horses is influenced by geographic location, breed, or PPID. Animals: Healthy light breed horses residing in Florida, Massachusetts, and Finland (n = 12 per group); healthy Morgan horses (n = 13); healthy ponies (n = 9) and horses with PPID (n = 8). Methods: Monthly plasma α‐MSH and ACTH concentrations were measured by radioimmunoassay. Nonlinear regression analysis was used to estimate the time of peak hormone concentrations. Mean hormone concentrations in fall and nonfall months were compared. Results: The fall peak plasma α‐MSH concentration occurred earlier in horses residing at more northern locations. Mean seasonal α‐MSH concentrations were similar in all healthy groups at all locations, but in the fall, plasma ACTH concentrations were higher in horses living in more southern locations. Plasma ACTH but not α‐MSH concentrations were higher in Morgan horses compared with light breed horses from the same location. Hormone concentrations of ponies did not differ from those of horses during either season. Concentrations of both hormones were high in the fall compared with the spring in horses with PPID. Conclusions and Clinical Importance: These findings suggest geographic location of residence and breed may affect the onset, amplitude, or both of the seasonal peak of pars intermedia (PI) hormones and should be considered when performing diagnostic testing for PPID. Horses with PPID maintain seasonal regulation of PI hormone output.  相似文献   
109.
7种鸭源细菌的分离与16S rDNA测序鉴定   总被引:1,自引:0,他引:1  
从病死鸭的脏器中无菌分离细菌.根据培养特性、菌落形态、革兰染色和生化特性,鉴定出7种细菌分离株.以分离株的基因组DNA为模板,用16S rDNA试剂盒扩增其DNA片段,测序后NCBI网站进行BLAST搜索比对,鉴定出细菌种类,分别为鼠伤寒沙门菌、大肠杆菌、鸭疫里默氏杆菌、铜绿假单胞杆菌、施氏假单胞菌、浅绿气球菌和麦氏棒杆菌.前3种为鸭的常见分离菌,其余的较为少见.因此在鸭病控制过程中应注意可能存在一些不常见细菌的混合感染.  相似文献   
110.
家蚕是重要的经济昆虫,也是鳞翅目昆虫的主要模式生物。表达序列标签(EST)在家蚕研究中的应用越来越受到关注。本文主要介绍了EST数据库的建立及其在家蚕研究中的应用现状,展望了EST在家蚕中的研究趋势。  相似文献   
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