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51.
渠道水力最优断面的程序设计及绘图 总被引:1,自引:0,他引:1
利用ActiveX Automation技术将Visual BASIC与AutoCAD链接,实现了常用渠道的水力最优断面设计及绘图的自动化,可明显提高渠道设计及绘图的工作效率。 相似文献
52.
We report on an outbreak of enzootic abortion in a herd of goats with high losses caused by mixed infection with Coxiella burnetii and Chlamydia psittaci. Both agents could be detected by microscopic investigation of smears from afterbirths by Giménez staining and by a capture enzyme-linked immunofluorescence assay (Capture ELIFA). Additionally, Coxiella burnetii was isolated from the same tissues in BGM cell cultures. Serological investigations with CF, indirect ELIFA, and IF tests revealed high antibody titers against both agents in most animals. Coxiella antigen was still detected 91 days later in milk samples of two infected goats by Capture ELIFA. 相似文献
53.
A Che?mońska-Soyta M Zimecki W Nowacki M Niko?ajczuk 《Comparative immunology, microbiology and infectious diseases》2001,24(3):151-164
We investigated the influence of heparin, one of the extracellular matrix (ECM) components, on nitric oxide (NO) and tumor necrosis factor-alpha (TNF-alpha) production by bovine peripheral blood mononuclear cells (PBMC) and monocytes left to adhere for 2 (freshly adherent monocytes) and 48 h (resting monocytes), activated with Salmonella typhimurium lipopolysaccharide (LPS). After 24-h stimulation with LPS, heparin (100 microg/ml) increased (by about 40%) NO production by peripheral blood mononuclear cells and by freshly adherent monocytes. However, it did not change NO synthesis by the resting monocytes. Unlike its influence on NO level, heparin diminished TNF-alpha production by PBMC and monocytes stimulated with LPS. Microscopical examination of PBMC stained with biotin-labeled heparin, showed that both lymphocytes and monocytes were able to bind this glycosaminoglycan. We suggest that heparin, as a component of ECM, modulates the early response of monocytes to exogenous stimuli. 相似文献
54.
用奶牛乳房炎多联苗 (B)免疫家兔 ,14 d血清中金黄色葡萄球菌抗体效价可达 1∶ 8,2 8d抗体水平明显升高 ,可达 1∶ 32 ,注苗后 35 d攻毒 ,攻毒后 2 d保护率为 93.3% (14 /15 ) ,自然保护率为 2 0 % (1/5 ) ,10 d保护率为 6 6 .6 % (10 /15 ) ,自然保护率为 2 0 % (1/5 ) ;用多联苗 (B)臀部肌肉注射免疫泌乳牛 ,试验期间 4个月内 ,3ml剂量组临床型乳房炎月平均发病率为 11.0 9% ,其对照组为 2 0 .19% ,发病率降低 4 5 .2 9% ,差异极显著 (P<0 .0 1) ;5 m l剂量组月平均发病率为 13.0 1% ,其对照组为 31.36 % ,发病率降低 5 8.5 1% ,差异极显著 (P<0 .0 1) ;3ml剂量组与 5 m l剂量组之间发病率无明显差异 (P>0 .0 5 ) ;注苗后泌乳牛血清抗体水平可持续 4个月 ,且 30 d时效价水平最高。 相似文献
55.
B Cancho Grande M S García Falcón M Rodríguez Comesa?a J Simal Gándara 《Journal of agricultural and food chemistry》2001,49(7):3145-3150
Sulfamethazine (SMZ) and trimethoprim (TMP) are antibacterials used in veterinary practice. This paper describes a method for their determination in veterinary liquid feed premixes that is based on liquid chromatography with diode array detection. Gradient elution with methanol and ammonium acetate achieved excellent separation of the two analytes within 15 min without any interference from the matrix. Absorbance of the column effluent was monitored at 264 nm for SMZ and at 230 nm for TMP. Detailed analyses of the uncertainties of determinations afford estimated expanded uncertainties of, respectively, 0.2 and 0.1 w/v % for typical SMZ and TMP concentrations of 10.7 and 2.1 w/v %, respectively. At the lower end of the calibrated range of the method, the dominant source of uncertainty is the preparation of standards and the construction of the calibration line. 相似文献
56.
W Rabsch A Liesegang H Tsch?pe 《Berliner und Münchener tier?rztliche Wochenschrift》2001,114(11-12):433-437
The Paul Ehrlich Institute, Langen, in Germany has been licensed different live vaccines of S. Typhimurium and S. Enteritidis for use in the veterinary medicine since I the 90s. The Robert Koch Institute has established a lab-based surveillance system for these live vaccine strains for an evaluation of recent public health safety. Since 2000 all strains of S. Typhimurium and S. Enteritidis from humans were investigated in respect to their phage types and other vaccine markers. 3676 S. Typhimurium strains and 4489 S. Enteritidis strains mainly from Salmonellose patients were investigated after phage typing according to their auxotrophic or antibiotic resistance markers. The live vaccine strains of Zoosaloral, TAD Salmonella vacT or TAD Salmonella vacE and Salmovac SE could not be found from infections in humans. 相似文献
57.
The influence of an eradication programme for lice on the prevalence of light flecks and spots on cattle hides was studied in 33 dairy cattle herds during a period of two and a half years. Lice were eradicated from the main group of herds after 9 to 12 months and the quality of the hides before and after treatment was compared. Hides from slaughtered animals were collected during the study period, tanned and examined with special emphasis on the occurrence of the grain damage light flecks and spots. The prevalence of hides without light flecks and spots increased from 24.2% before treatment to 61.6% after treatment. The prevalence of hides free from the damage increased significantly in all examined anatomical regions. The improvement in hide quality was most marked in the shoulders and neck region which corresponded to the major predilection site of cattle lice. The prevalence of hides with light flecks and spots started to decrease in the first period (2-40 days) after eradication. The changes after treatment suggested that most healing process took place over a period of about 4 months. The eradication programme eliminated the seasonal variation in the prevalence of light flecks and spots which was present before treatment. 相似文献
58.
T Kokkonen A Tsehai Tesfa M Tuori S Yrj?nen L Syrj?l?-Qvist 《Archives of Animal Nutrition》2002,56(3):213-227
Twenty-one multiparous dairy cows were fed concentrates containing three levels (119, 154 and 191 g/kg DM) of crude protein (CP) during the first ten weeks of lactation. Part of the grain and molassed sugar beat pulp was substituted with 0% (RSM0), 15% (RSM15) or 30% (RSM30) repeseed meal. Wilted grass silage was fed ad libitum after calving. The average response between RSM0 and RSM15 was +1.66 kg milk/d per percentage unit change in concentrate CP content. No further response occurred between RSM15 and RSM30. The positive effect of RSM inclusion was seen throughout the experimental period and was associated with increased plasma non esterified fatty acids (NEFA) and decreased plasma insulin concentration one week after calving, and higher efficiency of metabolisable energy utilisation for milk production. Digestibility of the diet remained unaffected. Milk and plasma urea tended to increase with RSM30 indicating excessive supply of rumen degradable protein. Because of the limited potential of cows to compensate for a deficit in feed protein supply by mobilising tissue protein, a substantial milk yield response can be achieved with a moderate level of protein supplementation during early lactation. 相似文献
59.
获能是哺乳动物精子的成熟过程和受精的必要前提,获能液中添加物从不同方面影响精子获能;本文阐述了肝素、Ca2 载体A23187、葡萄糖、孕酮、咖啡因等添加物对精子体外获能的影响及其作用机制。 相似文献
60.
经过冬蜜花期对以湖北鄂西中蜂为母本、广东粤东地中蜂为父本的杂交一代与本地中蜂进行比较,结果表明:杂交一代的繁殖力和产蜜量分别比本地中蜂高4.4%和11%。夏季乌桕花期对回交代进行对比结果表明:其繁殖力和产蜜量分别比本地中蜂高6%和21%。 相似文献