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1.
比格犬人工感染埃立克体病的临床研究   总被引:2,自引:0,他引:2  
为了表述比格犬感染埃立克体(Ehrlichia)后的临床表现,用已确证为E.platys和E.canis混合感染的犬血对5条比格犬进行了人工感染,并对临床和血液学变化进行了观察。埃立克体病的潜伏期为6-29天,其后的临床表现为急性发热、眼结膜苍白、厌食、精神沉郁、体重严重减轻、腹泻带血、多处有淤血斑点出现、6-45天内全部死亡。血液学变化显示血红蛋白和白细胞明显减少(P<0.01,P<0.05)。由此可见,比格犬对2种埃立克体(E.canis和E.platys)混合感染的性很高,严重的临床表现与美国学者普遍认为的亚临床状态相左,这可能是中国Gzh981株(E.platys)和Gzh982株(E.casnis)与国外株在毒力上的差异所致。  相似文献   
2.
To assess changes in 24 blood constituents in frozen serum and heparinized plasma, blood samples were drawn from 10 clinically normal German Shepherd army dogs. The storage characteristics of nine enzymes (ALP, ALT, amylase, AST, CK, GGT, GLDH, LDH, lipase), and 15 metabolites and minerals (albumin, bile acids, bilirubin, calcium, cholesterol, creatinine, fructosamine, glucose, magnesium, phosphate, potassium, protein, sodium, triglycerides, urea) were studied. Parallel samples of serum and heparinized plasma were stored for 90 and 240 days at two different storage temperatures, -200 degrees C and -700 degrees C. Sixteen of the 24 analytes (ALP, ALT, amylase, AST, CK, GGT, GLDH, LDH, bile acids, calcium, cholesterol, creatinine, fructosamine, magnesium, phosphate, urea) showed statistically significant (p < 0.05) changes during the storage period related to storage time, storage temperature, and sample type. Seven of the analytes (amylase, GGT, GLDH, LDH, bile acids, fructosamine, magnesium) showed changes of possible clinical importance with mean differences from baseline larger than 20% for the enzymes and 10% for the metabolites and minerals during the storage periods.  相似文献   
3.
AIM: To investigate the application of atomic force microscope (AFM) in clinic diagnosis. METHODS: Topographic images and some parameters of large range field and microstructures of erythrocytes in the blood of normal subjects, lung cancer and myelodisplastic syndrome (MDS) patients were examined by atomic force microscope. RESULTS: Many clear topographic images of many erythrocytes, single erythrocyte, and microstructure of erythrocyte membrane surface were obtained. Many erythrocytes in lung cancer patients were found to change into echinocytes. One erythrocyte had 10-20 protuberances, most of which, with a mean width of 589. 0 nm and a length of 646. 7 nm, were on the edge of cells. The protuberances on the center of echinocytes are lodged and embedded. The erythrocytes of MDS patients were biconcave in shape. Many apertures with different diameters of tens to hundreds nanometer appeared on the surface of cell membrane. CONCLUSIONS: AFM can be widely applied in clinic pathological inspection, including quantification of cells, obtainment and comparison of many parameters (such as diameter, thickness, volume, surface, surface area/volume ratio), observation of topograph of single cell, and observation and comparison of membrane surface microstructure of cells, and so on.  相似文献   
4.
Infection of potato plants with Tobacco rattle virus by its nematode vector can have different outcomes, including the development of spraing symptoms in progeny tubers. A novel syndrome described here comprises a generalized mottle in leaves on all stems, together with virtually total failure to produce daughter tubers. The outcome of infection depends partly on the potato genotype, but field trials with 15 varieties showed that the incidence and severity of spraing symptoms at three sites differed. There was no evidence that this was due to differences in virulence among the virus isolates at the sites, but it was probably the result of environmental differences that influenced the numbers and activity of the vector nematodes. At the most severely affected site, spraing symptoms were found in all varieties tested, except Record, including several that were not affected at the other two sites. Taking both severity and incidence of symptoms into account, the ranking of varieties was similar at each site. The incidence of spraing symptoms was greater in larger than in smaller tubers, and increased with later harvest dates, but did not increase when early harvested tubers were stored. Tobacco rattle viruswas detected in the roots of many of the weeds growing at one of the sites and in the roots of a few plants of the subsequent barley crop.  相似文献   
5.
为了提供有效的伪狂犬病疫苗,用鸡胚成纤维细胞扩大培养了PrV HB-98突变株(TK^-/gG^-/LacZ^+),研制了伪狂犬病基因缺失疫苗,并对该疫苗经肌肉接种、经口等免疫途径的最小免疫剂量进行了测定,同时也对4批疫苗的安全性、效力、免疫期和保存期进行了检测;同时将4批疫苗用于免疫23个猪场的母猪、新生仔猪和育肥猪进行区域试验。测定结果表明,疫苗经上述两种途径接种对不同阶段猪的最小免疫剂量均为10^5.0 TCID50;10倍免疫剂量的疫苗对初生仔猪、15日龄仔猪和妊娠母猪是安全的,免疫猪能抵抗强毒的攻击;疫苗在4℃和-20℃下分别可保存6个月和12个月。对伪狂犬病毒抗体阴性的70日龄商品猪和种猪的免疫期为6个月。田间试验表明,4批猪伪狂犬病基因缺失疫苗安全有效,并可用于仔猪发病时的紧急接种。为猪伪狂犬病基因工程疫苗的制备与应用提供了有力的依据。  相似文献   
6.
采用调查问卷和临床问诊的方法对湖南省株洲市马加村随机抽样的252名留守村民进行调查,共发放调查问卷264份,回收问卷252份,回收率95.5%。调查表明:81.7%的被调查者有不同程度的身体疾病,其中血压偏高者57.3%,长期肌肉疼痛者69.4%,关节、骨异常者52.9%,腰间盘突出者16%。在此基础上,对影响留守村民的健康的因素进行了分析。  相似文献   
7.
Routine agricultural practices are heavily dependent on the use of surfactants, many of which are toxic to humans and detrimental to the environment. In proof of concept work we have previously shown the potential of nanostructured liquid crystalline particles (NLCP) to safely interact with plant leaf cuticular surfaces with minimal impact on epicuticular waxes. Here we demonstrate the use of NLCP to effectively deliver the auxin herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) to plant leaves in laboratory and field studies. In the laboratory, the physiological stress responses of lupin, Lupinus angustifolius (L.) (Fabaceae) towards NLCP spray applications were shown to be much reduced in comparison with application of two common surfactants. Phytotoxicity assays of 2,4-D loaded NLCP were used to validate the herbicidal effects on Arabidopsis thaliana (L.) Heynth. (Brassicaceae) and established a similarity with that of surfactant assisted 2,4-D delivery when tested at a concentration of 0.1%. Field trials were conducted to test the efficacy of NLCP-assisted delivery of 2,4-D in comparison with commercial surfactants for the control of the invasive weed wild radish, Raphanus raphanistrum (L.) (Brassicaceae), in wheat, Triticum aestivum (L.) (Poaceae) crop fields. Compared against Estercide 800, a commercially available 2,4-D formulation, NLCP assisted delivery of 2,4-D was effective at low concentrations of 0.03% and 0.06%. The crop yield remained similar for all the tested concentrations and formulations of 2,4-D loaded NLCP and Estercide 800. This is the first report to directly show that, as an alternative to conventional methods, NLCP can be used under both laboratory and field conditions to successfully delivery an agrochemical.  相似文献   
8.
In Hungary, maize is grown on 1 million ha and occupies more than 20% of the arable land. The rich assortment of maize cultivars of different vegetation periods and different responses to nutritional effects, water supply etc. gives the growers the possibility to choose the cultivars suiting best the site characteristics (Jolânkai et al. 1999). Among the cereals maize has the highest genetical potential. To utilize its yield and quality potential, soil types of high nutrient content and regular nutrient supply are required (Gyõrffy, 1979). Both over‐ and under‐fertilization have an unfavourable effect on the yield and quality of maize (Debreczeni, 1985). Crops can be supplied with the appropriate nutrient amounts only with the knowledge of soil characteristics in the different agro‐ecological regions (nutrient content, water supply, soil compactness, pH, nutrient supplying capacity etc.). In Hungary, a network of long‐term field fertilization trials with uniform fertilizer treatments has been maintained at nine experimental sites representing different agro‐ecological regions of the country. This experimental network gives a basis to test the nutrient responses of our main crops and calibrate their optimal nutrient supply (Kismányoky, 1991).  相似文献   
9.
猪丹毒     
猪丹毒又称“红热病” “打火印”或“钻石皮肤病”,是一种急性的、热性的传染病,引起该病的病原为红斑丹毒丝菌,可以通过伤口感染人,也是一种人兽共患病。患病猪的临床表现形式大致可分为3种类型,即急性、亚急性和慢性型。急性型病例主要的表现为出现明显的败血症症状。亚急性型病例则是在四肢、胸腹部、背部等皮肤处出现红色菱形、方形或圆形疹块。慢性型则多以出现关节炎和心内膜炎引起的关节肿胀、运动障碍和心跳加速、呼吸急促为主的临床表现;有时还可见皮肤坏死。红斑丹毒丝菌的最易感动物是猪,没有品种和年龄差异。使用疫苗是最佳的预防手段,治疗方面除使用抗生素外还可以选择中药方剂进行治疗。  相似文献   
10.
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