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1.
为明确中国在"一带一路"沿线国家所形成的科技网络中处于怎样的位置,面临怎样的科技情报风险,需要采取哪些措施维护中国科技情报安全,应用智库DIIS理论方法,对科学引文索引中2013年-2017年"一带一路"沿线国家论文合作数据进行社会网络分析,应用管理机制设计"七元组"理论开展科技情报安全机制设计。研究结果显示,中国科技情报的暴露程度较高,科技应用的不可控因素、知识产权保护的挑战、科技情报资源流失的风险同时存在,并与各种非传统安全问题相叠加。切实掌握核心技术,维护知识产权,加强政府、社会对科技交流的监管,防止科技情报被非法利用,是保障科技情报安全的主要途径。 相似文献
2.
“基础化学”理论和实验教学质量的“高与低”在一定程度上直接关乎高职院校与化学相近专业人才培养的“成与败”。以教学改革为切入点,在“基础化学”教材建设和系列微课的制作及应用2个维度上,探讨提升“基础化学”课程教学质量的具体措施。 相似文献
3.
The effects of collection regimen and time of year on rabbit semen production were determined in this study. A total of 14 crossbreed Hyla bucks were used in winter and summer. In each season, rabbits were assigned to two groups. In group 1, (n = 7) rabbits were subjected to an extensive collection regimen (two ejaculates per male, once daily/week) and in group 2, (n = 7) a semi‐intensive semen collection regimen was performed (two ejaculates per male, twice weekly). The traits recorded for each sample were libido, volume, pH, motility, sperm concentration, percentage of alive spermatozoa and sperm abnormalities. The results obtained in this study indicate that when increasing collection frequency, the rate of useful collections decreased (from 0.81 ± 0.017 to 0.69 ± 0.016; p < 0.01). The rate of useful collection also decreased in the transition from winter to summer (from 0.79 ± 0.018 to 0.70 ± 0.017; p < 0.01). Among the ejaculate characteristics studied, only volume/ejaculate (from 0.64 ± 0.015 to 0.53 ± 0.017; p < 0.01) and spermatozoa/ml (from 406 ± 15 to 359 ± 13 million; p < 0.01) appeared negatively affected by collection. In winter fewer volume/ejaculates were produced (0.55 ± 0.015 vs 0.60 ± 0.016 ml; p < 0.01) and fewer spermatozoa/ml (360 ± 14 vs 394 ± 16 million; p < 0.01) than in summer. The doses produced per ejaculate decreased as collection frequency increased, but the number of doses produced per week was higher in the semi‐intensive than the extensive rhythm (26.5 ± 2.1 vs 20.9 ± 1.5; p < 0.01). The results suggest that a semi‐intensive rhythm may be viewed favourably. 相似文献
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F. Gentilini C. Calzolari A. Buonacucina M. Di Tommaso G. Militerno P. Famigli Bergamini 《Veterinary and comparative oncology》2005,3(2):87-97
Waldenström Macroglobulinemia is a low‐grade immunosecretory disorder associated with lymphoid tumours, which is rarely reported in veterinary medicine. In this study, we describe two clinical cases of this rare syndrome in dogs, each characterized by a different onset and clinical course. In one case, a hyperacute onset and aggressive behaviour of the neoplasm was observed. Absolute serum viscosity (SV) was retrospectively evaluated in order to explain clinical findings. Rotational viscosimetry showed good precision in measuring SV. Both dogs had SV values higher than a control groups of healthy dogs although only one subject developed hyperviscosity symptoms and complications. At high paraprotein concentrations, a slight reduction of the M‐component was associated with a marked decrease in SV. Thus, this work suggests that SV assessment is a relevant tool for managing monoclonal gammopathies, whose usefulness should be further confirmed in larger cohorts of dogs. 相似文献
6.
D. Boscia H. Zeramdini M. Cambra O. Potere M.T. Gorris A. Myrta B. Di Terlizzi V. Savino 《European journal of plant pathology / European Foundation for Plant Pathology》1997,103(5):477-480
A monoclonal antibody to an Albanian isolate of plum pox potyvirus (PPV) was obtained (MAbAL), that specifically recognized strain M of this virus. The specificity of MAbAL, assessed by comparative ELISA on 130 PPV isolates of different geographical origin, 22 of which were also tested by comparative IC-PCR, gave consistent and highly reproducible results. MAbAL seems to be elicited by a stable surface determinant that makes it particularly suitable for successful use under a wide range of conditions. MAbAL is an useful addition to the panel of PPV-specific MAbs available to date. 相似文献
7.
Leslie Boerner Kathleen R Nevis Lynn S Hinckley E Scott Weber Salvatore Frasca 《Journal of veterinary diagnostic investigation》2004,16(2):145-149
On June 25, 2002, aquarium veterinarians treated a 5-year-old, male little blue penguin (Eudyptula minor) that was acutely recumbent and dull, with inappetence of 24-hour duration. The penguin died within 10 minutes of presentation despite emergency resuscitation efforts. Gross pathologic findings consisted of pulmonary congestion and intestinal hemorrhage. Histopathologic findings included necrosis of tips of intestinal villi, increased numbers of mononuclear cells in pulmonary interstitium and hepatic sinusoids, and gram-positive bacteria in systemic microvasculature. Transmission electron microscopic examination revealed short gram-positive bacilli located in lumina of glomerular capillaries and in cytoplasm of mononuclear phagocytic cells in the lung and liver. Erysipelothrix rhusiopathiae was recovered from the lung, liver, and intestine by bacteriologic culture. Amplicons from polymerase chain reaction (PCR) tests using Erysipelothrix genus-specific primers and total genomic DNA extracted from formalin-fixed, paraffin-embedded tissue sections of lung and intestine demonstrated 99% nucleotide sequence identity with 16S small-subunit ribosomal DNA of E. rhusiopathiae and E. tonsillarum. The source of infection was speculated to be fish in the diet; however, repeated attempts to detect Erysipelothrix spp. from the mucous layer of food fish using bacteriologic culture and PCR were unsuccessful. This is the first report of erysipelas in a captive aquatic bird. Details of the isolation of E. rhusiopathiae and the application of molecular testing to identify Erysipelothrix DNA in formalin-fixed, paraffin-embedded tissue sections are given. 相似文献
8.
Paolo Zucca Giovanni Di Guardo Roberto Pozzi-Mucelli Dino Scaravelli Marco Francese 《Journal of zoo and wildlife medicine》2004,35(3):391-394
A mature male Risso's dolphin (Grampus griseus) stranded along the coasts of Friuli Venezia Giulia, northeast Italy, in May 2001. Parasitic infection with Crassicauda grampicola is often found in the tympanic bullae and pterygoid sinuses in many of the Risso's dolphins examined from the same area. For this reason, it was decided to perform computed tomography of the head to assess this imaging technique for the diagnosis of crassicaudosis in dolphins. A full postmortem examination confirmed the pathologic findings of the computed tomography scan. This technique can be considered a useful adjunct in the diagnosis of cranial crassicaudosis in live dolphins. 相似文献
9.
Colour Flow Mapping examination: An useful screening test for the early diagnosis of ductus venosus patency in canine newborns 下载免费PDF全文
Monica Melandri Gabriele Barella Giulio Aiudi Giovanni Michele Lacalandra Salvatore Alonge 《Reproduction in domestic animals》2018,53(5):1130-1135
Ductus venosus (DV) closure plays a key role in hepatic circulation adaptation to postnatal metabolic function, and DV patency might develop a congenital portosystemic shunt (CPSS). The noninvasive Color Flow Mapping (CFM) examination, a validated method to diagnose CPSS in adult dogs, is routinely performed to assess DV closure after birth in humans. This study aimed to describe the feasibility of the ultrasonographic evaluation of the DV after birth and to determine its closure time in healthy Great Dane neonates. Patency of DV in serial Color Flow Mapping (CFM) examinations and bodyweight (BW) were recorded on Days 0‐3‐6‐9 in 24 neonates that were classified as having patent (PDV) or closed ductusvenosus (CDV) basing on CFM signal presence/absence. Since the 3rd day, DV diameter was recorded. Data were analysed by ANOVA (p < 0.05). All dogs resulted healthy 1 year later. The number of PDV and CDV puppies at birth was not different on Day 3 (24 and 0 vs. 22 and 2, PDV and CDV, respectively), whereas it resulted different on Days 6 (24 and 0 vs. 14 and 10) and 9 (24 and 0 vs. 0 and 24); on Day 3, it was different compared to Days 6 and 9; on Day 6, it was different from Day 9. Reduction of DV diameter resulted positively related to neonatal BW growth. The CFM evaluation of DV closure after birth in Great Dane puppies represents a feasible technique. Present results suggest the time of functional closure in normal neonates within 9 days after birth. Thus, CFM examination, as an early screening test for DV patency evaluation, performed 10 days after birth, may identify suspicious dogs at risk that would require further investigations. Further studies are needed to deepen the role of a delayed closure in low bodyweight and preterm puppies. 相似文献
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