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51.
In 4 dairy farms located in Baotou area, clinical medicine investigation and drug resistance of pathogenic bacteria were conducted, and then curative effects of different treatment methods were analyzed.Epidemic materials were collected from diary cows infected by endometritis, from which pathogenic bacteria were isolated using conventional microbiology technologies.Broth microdilution method was used to detect the sensitivity and resistance of pathogenic bacteria to antibiotics commonly used in clinic.On this basis, the sensitive drugs were used to treat mastitis or endometritis, the clinical curative effect of traditional treatment group was compared with that of therapeutic test group.The result of traditional treatment group showed 13 antibiotics were used to treat 160 cases of endometritis, florfenicol was most effective, penicillin was most ineffective.The results of therapeutic test group showed that Staphylococcus aureus, Escherichia coli and Streptococcus were the main pathogenic bacteria of endometritis, which were sensitive to gentamicin and cefalotin, etc.The results of statistical analysis showed that the curative effect of therapeutic test group was extremely significantly different from that of traditional treatment group(P<0.01).Sensitive drugs screened by drug sensitive test could be used to target therapy, and obtain satisfied curative effect.Moreover, this approach could avoid antibiotic abuse.  相似文献   
52.
针对QY、PRI、NDVI、水势分别从不同的方面反映玉米的生理状况,以甜糯二号玉米作为材料,通过田间试验测量玉米昼夜4个参数值,研究了QY、PRI、NDVI、水势4个参数的昼夜变化,并且分析它们之间的相关性。结果表明,QY、水势、PRI三者具有很强的相关性,并且能建立回归模型表示它们之间的联系。  相似文献   
53.
以不同发情周期雌性绵羊子宫、输卵管为研究对象,采用免疫组织化学技术,针对血管内皮生长因子(VEGF)在绵羊子宫、输卵管的表达、定位和变化规律进行了检测,同时应用相关图像分析软件对抗原染色强度进行了定量分析。结果表明:输卵管在发情0~15d,VEGF表达量在第9天达到峰值后经历波动逐渐下降过程,输卵管内膜上皮细胞是VEGF抗原的主要靶细胞;而子宫角在发情0~15d,VEGF表达量在第5天达到峰值后经历波动逐渐下降过程,子宫内膜固有层及腺体周围细胞为VEGF抗原的主要靶细胞。该研究结果为绵羊生产中进一步提高受胎率和妊娠率及频密产羔等技术的应用提供了科学依据。  相似文献   
54.
水分条件对巴音布鲁克高寒湿地CO_2排放的影响   总被引:1,自引:0,他引:1  
在新疆天山中部巴音布鲁克天鹅湖高寒湿地,以苔草(Carex tristachya)为主要建群种的样地为研究对象,利用英国PP-systems公司生产的便携式土壤呼吸测定系统(CIRAS-2-SRC)研究了不同地表水分条件对天鹅湖高寒湿地夏季土壤CO2排放的影响。结果表明,1)湿润区的生物量大于干燥区;干燥区土壤CO2排放高于湿润区,干燥区土壤CO2排放日变化曲线为单峰曲线,CO2排放最高点出现在当地14:00-16:00,最高值为1.185 0g CO2·m-2·h-1;湿润区土壤CO2排放日变化曲线为双峰曲线,两个峰值分别出现在12:00和16:00,最高值为1.024 0g CO2·m-2·h-1。2)不同水分条件下生物量中凋落物含量影响土壤CO2排放。土壤温度是CO2排放的主要限制因子,且地表干燥区CO2排放与土壤温度的相关性更显著(P0.01)。土壤湿度与CO2排放相关性不显著(P湿润区=0.997,P干燥区=0.409)。  相似文献   
55.
陇薯9号的品种特性及脱毒种薯繁育技术   总被引:1,自引:0,他引:1  
介绍了新品种陇薯9号的品种特征,并就其脱毒种薯繁育体系的核心要领和关键技术作了阐述.  相似文献   
56.
Pseudorabies virus (PRV) infection leads to severe inflammatory responses and tissue damage, and many natural herbs exhibit protective effects against viral infection by modulating the inflammatory response. An ethyl acetate fraction of flavonoids from Polygonum hydropiper L. (FEA) was prepared through ethanol extraction and ethyl acetate fractional extraction. An inflammatory model was established in RAW264.7 cells with PRV infection to evaluate the anti-inflammatory activity of FEA by measuring cell viability, nitric oxide (NO) production, reactive oxygen species (ROS) release, and mRNA expression of inflammatory factors, inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2). Its functional mechanism was investigated by analyzing the phosphorylation and nuclear translocation of key proteins in the nuclear factor-kappa B (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways. Our findings indicate that PRV induced inflammatory responses in RAW264.7 cells, and the responses were similar to that in lipopolysaccharide (LPS)-stimulated cells. FEA significantly suppressed NO synthesis and down-regulated both expression and secretion of COX-2, iNOS, and inflammatory cytokines (P<0.05 or P<0.01). FEA also reduced NF-κB p65 translocation into the nucleus and decreased MAPK phosphorylation, indicating that the NF-κB/MAPK signaling pathway may be closely related to the inflammatory response during viral infection. The findings suggested the potential pharmaceutical application of FEA as a natural product that can treat viral infections due to its ability to mitigate inflammatory responses.  相似文献   
57.
AIM: To investigate the effect of paricalcitol (P) on renal tubulointerstitial fibrosis and the underlying mechanisms in diabetic nephropathy (DN).METHODS: DN rat model was induced by a single intraperitoneal injection of streptozotocin after fasting. The animals were randomly divided into 2 groups:the DN rats in paricalcitol-intervened group (group P) were injected intraperitoneally with paricalcitol dissolved in propylene glycol after the day when the model was induced successfully at a dose of 0.4 μg/kg (3 times a week); the DN rats in DN group (group D) were given isopyknic propylene glycol. Normal control group (group C) was also set up. The samples of blood, urine and renal tissue were collected after intervention of paricalcitol for 12 weeks. The biochemical indexes were measured. The renal tissues were used for pathologic observation and determining the expression of transforming growth factor-β1 (TGF-β1), Wnt-4, β-catenin and Klotho by immunohistochemistry and Western blotting. In addition, the correlation among the above indexes was analyzed.RESULTS: (1) Scr, BUN and 24 h urine protein increased significantly in group D compared with group C, while decreased in group P compared with group D (P<0.05). (2) The area of renal tubulointerstitial fibrosis increased in group D compared with group C, while decreased in group P compared with group D (P<0.05). (3) The expression of Klotho decreased, while the expression of TGF-β1, Wnt-4 and β-catenin increased in group D compared with group C (P<0.05). Compared with group D, the expression of Klotho increased, while the expression of TGF-β1, Wnt-4 and β-catenin decreased in group P (P<0.05). (4) The expression of Klotho was negatively correlated with the fibrosis area, TGF-β1, Wnt-4 and β-catenin (P<0.05).CONCLUSION: Paricalcitol inhibits renal tubulointerstitial fibrosis in DN by promoting the expression of renal Klotho, and inhibiting Wnt/β-catenin signaling pathway activation and TGF-β1 synthesis.  相似文献   
58.
To explore the value of Mb1230 protein of Mycobacterium bovis in the diagnosis of bovine tuberculosis,we obtained the Mb1230 gene by PCR and constructed recombinant plasmid pET-22b-Mb1230.Recombinant Mb1230 protein was obtained by IPTG induction and purified by affinity chromatography.The activity of the recombinant protein was evaluated by TST test,IGRA test and indirect ELISA.The size of the recombinant protein matched with the theoretical value proved by SDS-PAGE;Western blotting result showed that the recombinant protein could react with mouse anti-His antibody,and had specific band;The results of TST test,IGRA test and indirect ELISA test also showed the recombinant protein had antigenic activity.The results indicated the recombinant protein Mb1230 had good B cell and T cell activity,so,it had the potential application in the diagnosis of bovine tuberculosis.  相似文献   
59.
木耳菌糠袋栽滑菇配方研究   总被引:1,自引:0,他引:1  
本试验采用不同比例的木耳菌糠替代部分木屑袋栽滑菇,以培养料(木屑89%、麦麸10%、石膏1%)为对照,探讨木耳菌糠栽培滑菇的可行性。结果表明,木耳菌糠添加量25%~45%时,可缩短发菌天数,其中菌糠添加量为45%时,满袋天数仅需52 d,并且长势较好;但菌糠添加量为55%~65%时,则延长了发菌天数,而且菌丝稀疏,长势也弱。对照(CK)与木耳菌糠添加量是25%~45%时,子实体生长良好,并且出菇整齐;菌糠添加量为55%~65%,则出菇不整齐。CK的生物学效率最高,但配方4(菌糠45%、木屑34%、麦麸10%、石膏1%)的生物学效率与CK差异不大,从成本和生态效益考虑,配方4栽培滑菇具有可行性,并已在广灵县进行推广。  相似文献   
60.
集体林产权制度改革是一项涉及广大农民群众切身利益的深刻变革,是广大农民群众的强烈愿望及社会发展的必然,只有这样才能实现经济社会可持续发展,才能明晰产权、放活经营、规范流转兴林富民,为构建和谐社会服务.  相似文献   
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