鲍曼不动杆菌雏鸡分离株CCGGD201101的分离、鉴定及致病性研究简

试验旨在鉴定吉林省某雏鸡孵育基地病死雏鸡组织中分离出的1株致病性菌CCGGD201101株并测定其致病性。对疑似致病菌进行生理生化试验、16S rDNA测序鉴定，并人工接种昆明鼠，测定其半数致死量，验证细菌毒力。经鉴定该菌为鲍曼不动杆菌（Acinetobacter baumannii）。以鲍曼不动杆菌CCGGD201101分离株为研究对象，并以鲍曼不动杆菌标准株（ATCC 19606）为对照，测得半数致死量，进一步证明鲍曼不动杆菌病死鸡分离株CCGGD201101具有较强致病性。     

副猪嗜血杆菌感染豚鼠试验及在其体内的分布

为了评估副猪嗜血杆菌(Haemophilus parasuis)对豚鼠的毒力以及在豚鼠组织器官的分布,作者采用改进的寇氏法测定了H.parasuis血清5型标准株对豚鼠的LD50,以1 LD50剂量经鼻腔、气管、肺、腹腔、肌肉和皮下接种感染豚鼠,比较不同途径感染H.parasuis对豚鼠致病性的差异;以1 LD50剂量气管接种豚鼠,接种后在不同时间取豚鼠的脑、心、肝、肺、脾和肾组织,制作石蜡切片,用免疫组化技术检测H.parasuis在豚鼠上述组织的分布.结果显示该H.parasuis血清5型标准株的LD50为1.33×109 CFU,LD50的95%可信限范围为1.35×109～1.30×109 CFU;感染试验结果显示,气管、肺和腹腔3个接种途径试验组豚鼠出现了4/8、2/8和5/8的死亡;在气管感染豚鼠6 h后,首先在肺脏组织呈现阳性结果,在感染8 h后,上述组织中都出现了阳性结果.结果表明气管、肺、腹腔和肌肉4个途径都可以使H.parasuis对豚鼠致病,免疫组化检测并结合细菌分离结果表明H.parasuis感染后能侵染肺、心、肝、脾和肾组织,并能突破血一脑屏障而侵染脑组织.     

猪链球菌耐药性产生对其毒力的影响

为探讨猪链球菌2型菌株耐药性产生对其毒力的影响,作者采用次抑菌浓度的青霉素和红霉素诱导猪链球菌2型临床分离敏感株HA9801成为青霉素、红霉素耐药株,并对亲本株与诱导耐药株的半数致死量（LD50）、溶血环、毒力因子溶菌酶释放蛋白（MRP）、胞外蛋白因子（EF）和荚膜多糖（CPS）及对小鼠的组织损伤进行比较。结果显示：次抑菌浓度的红霉素和青霉素可以诱导耐药性的产生,但耐药株与亲本株比较,溶血性、LD50、MRP、CPS、EF及对组织的损伤程度均与亲本株无显著差异（P〈0．05）。结果表明：猪链球菌2型HA9801株在获得耐药性的同时,仍能保持与亲本株相似的毒力,其毒力不会因耐药性的获得而降低。     

基于1:5万数据库研究土壤空间分异及其影响因素——以江苏省无锡和常州市为例

土壤数据库在土壤学研究工作中作为一种存储、分析工具的重要性是不言而喻的.本研究利用ArcGIS和Visual FoxPro建立了包括8 830个图斑、269个土壤剖面数据的无锡和常州市1：5万土壤数据库,根据“土壤质量演变规律与持续利用‘973＇项目”的土壤肥力质量指标（pH、速效磷和速效钾）和全国养分分级标准（全氮）编制出土壤表层（0～15 cm）pH、全氮、速效磷和速效钾的空间分异图,从中表明pH 1～2级的土壤占整个研究区面积90%左右;土壤养分全氮、速效磷和速效钾的空间分布有明显共同特征-太滆平田区养分含量要显著高于其他地区.对不同母质和不同土壤类型（亚类级别）间的土壤表层容重、粘粒、pH、有机质、全氮、全磷、全钾、速效磷和速效钾进行了方差分析,结果显示,除全氮之外,其他属性均有显著差异.在1：5万尺度范围内,成土母质对pH、容重、全磷、有机质和速效钾起到主导作用,土壤类型对pH起到主导作用,成土母质对土壤属性的影响程度要大于土壤类型.     

Pesticide toxicity using protozoans as test organisms

Summary A toxicity test using protozoa as test organisms was devised for pesticides. Two different methods were used, the most probable number method and the absorbance method (based on measurement of protozoa growth through absorbance). The ciliates Colpoda cucullus and Blepharisma undulans and the flagellate Oikomonas termo were isolated from different biological starter cultures and tested with the herbicides Chlorex, MCPA, dichlorprop and Matrigon, the fungicide Benlate, and the insecticide Sumicidin. The protozoans showed quite different sensitivities to the pesticides, using 9-h lethal concentrations (LC₅₀ and LC₁₀) as criteria. The 9-h LC₅₀ (concentration at which 50% of the protozeon population has died after 9 h of incubation) ranged from 0.7 ppm for Benlate to 40000 ppm for Chlorex. The usual soil application rates of Chlorex, MCPA, and Benlate were toxic to some of the organisms.     

Copper in the terrestrial environment: Verification of a laboratory-derived terrestrial biotic ligand model to predict earthworm mortality with toxicity observed in field soils

This study was set up for validation of a regression model to predict mortality in the terrestrial earthworm Aporrectodea caliginosa following exposure to copper. This model was derived from a terrestrial biotic ligand model and incorporates the protective effects of H⁺ and Na⁺ on copper toxicity.Three soil sets were used for the experiments, all of which had a different copper contamination history over more than 20 years and were considered to be aged field soils. The soils were characterized by analysis of various copper pools in the solid phase and in the pore water, analysis of physical and chemical soil properties and by regression analysis. Measured and calculated copper activities (expressed as pCu) correlated reasonably well. Measured copper activities correlated with the total copper concentration in the pore water and the pH. The organic matter in the solid phase had no influence on the pCu in these soil sets.Earthworms were exposed to the soils for 28 days, after which survival was scored. Observed earthworm mortality after 28-days exposure was plotted as a function of the log-transformed difference between predicted (log₁₀ transformed) LC50-values and measured values of pCu for validation of the regression model. The results obtained were in agreement with the assumption that mortality is to be observed in those soils where the predicted LC50 exceeds the measured pCu. However, a structural underestimation of toxicity was apparent, which is most likely due to mixture effects related to the presence of additional substances in field soils. Nevertheless, the trend of the results in the validation tests demonstrates that the newly developed toxicity model is a useful tool in predicting lethality of copper contamination to earthworms in field soils.     

皖麦50分蘖成穗的综合分析

[目的]为皖麦50的推广种植提供理论依据。[方法]通过田间试验对不同种植密度和不同产量水平下皖麦50群体的分蘖动态进行了综合分析。[结果]皖麦50冬前单株茎数与叶龄的回归方程为Y=0．1531e0.6199x；冬前出叶数与总积温的回归方程为z=1．199 10.0042∑1；冬前单株分蘖数与积温的回归方程为y=0．01531e0.01281∑τ；穗粒数和穗粒重与单株穗数的回归方程分别为y1=36．20＋1．7546x和y2=1．390＋0．0682x；株高与蘖住高度的回归方程为y=87．6054—1．9791x。当B基本苗为170万～220万／hm2，冬前单株分蘖数为5．5～6．5，群体总头数为950万-1050万／h2，单株成穗数为3．8，总穗数为632．91万／hm2时，皖麦50群体协调、高产。当有效穗数为600万一675万／hm2，穗粒数为33～35粒，千粒重为40～42g时，皖麦50的产量在7500kg／hm2以上。[结论]该品种高产稳产且易干蔷培营弹．在．准北抽．区及苦淮南片砉区有宦辑的庸用莆号．     

OK-50特效吸油材料的性能研究

通过试验，将公司自主研发的特效吸油材料OK-50应用于不同的油品吸附中，研究其适用油品种类、吸油量和保油率，得出该材料吸油倍率高，保油率也较高，使用范围较为广泛，应用前景广阔。     

中兽药胃动力散的安全性研究

为提供胃动力散的安全性毒理学评价资料，采用改良Ｋａｒｂｅｒ法测定小鼠ＬＤ５０；以剂量递增法测定小鼠蓄积性和耐受性；分别以剂量２２３９０ｍｇ／ｋｇ、８９６０ｍｇ／ｋｇ、４４８０ｍｇ／ｋｇ为３个试验组，设阴性和阳性对照组进行小鼠骨髓微核试验；分别以剂量３６０００ｍｇ／ｋｇ、１８０００ｍｇ／ｋｇ、９０００ｍｇ／ｋｇ为３个剂量组，设阴性和阳性对照组进行小鼠精子畸形试验，结果表明：其中ＬＤ５０为４４７７８ｍ     

超氧化物歧化酶在苜蓿抗寒锻炼过程中的作用

对苜蓿Medicago sativa抗寒锻炼过程中膜透性和超氧化物歧化酶(SOD)活性进行测定,通过苜蓿组织冰冻半致死温度(LT50)说明在抗寒锻炼过程中苜蓿抗寒性的变化。结果表明,在不同低温处理下,苜蓿叶片和根茎组织电解质透出率呈现出S型曲线变化。抗寒锻炼过程中,苜蓿组织LT50从9月初的-6.9℃下降到11月初的-15.6℃,下降了8.7℃。随着秋季气温的下降,苜蓿叶片SOD活性显著增加,11月上旬达到最高峰,此后显著下降。这说明SOD在抗寒锻炼过程中起着重要的保护作用,当苜蓿获得抗寒能力后,SOD活性逐渐下降。在抗寒锻炼过程中,苜蓿根茎SOD活性的变化与叶片中SOD活性的变化规律不一致,苜蓿根茎中SOD活性水平显著高于叶片中的SOD活性水平。聚丙烯酰胺凝胶电泳分析结果显示,不同苜蓿品种具有6条共同的SOD同工酶酶带。适应高寒地区气候条件的当地材料同德杂种苜蓿表现出与其他苜蓿品种较大的特异性。抑制试验表明苜蓿SOD为CuZn-SOD。