Clearance of ovine isolates of Bordetella parapertussis from murine trachea and lungs

Thirty-six mice were inoculated intranasally with Bordetella parapertussis organisms (isolated from sheep with chronic non-progressive pneumonia) to study their deposition and clearance in the lower respiratory tract. The deposition of the organism was greater in the trachea than in the lungs. At 48 hours after inoculation, almost 100% of organisms were cleared from the trachea but only 55% of organisms were cleared from the lungs. This result correlates well with the morphological changes seen previously in the pulmonary parenchyma and airways of mice and lambs experimentally infected with this organism.     

小麦赤霉病流行预测初步研究

对1952—1963年病害流行程度与穗期气象要素之間的相关性测定結果表明,各年发病程度与4月下旬至5月下旬(小麦抽穗至糊熟)特別是5月上中旬(小麦开花至灌浆初期)的降雨日数、相对湿度呈明显的正相关;与同期的降雨量、平均气温相关不显著。稻桩上产生的子囊壳是本地区初侵染的主要来源,初侵染的数量和流行程度有关,其数量积累决定于雨湿条件。小麦开花灌浆初期最易感病,此时期降雨日数是病害流行的决定性因素。根据十二年資料分析結果,病害流行可以分为六种类型:早期发生型;中期发生型;后期发生型;少雨限制型;低温限制型;生育提早限制型。根据1957—1963年預测圃小麦开花后二旬內的降雨日数与发病率的相关,以发病率为应变量求出迴归方程式:Y=6.61 X—48.35,为中期預測提出雨日指标。     

油茶炭疽病的综合防治

1962—1963年在四川省泸县地区进行油茶炭疽病的防治試驗。結果表明:采用营林措施(修除树上病部)和化学保护(噴射1∶1∶150波尔多液)的综合防治方法,病株防治效果可达89.77％,防止果病率达70.02％。严重病区,可在冬(12月)、春(2月)修除病部各一次(或可集中在2月进行),发病期間(4—8月)噴射波尔多液8—10次(条件不許可山区,也至少5次)。噴药宜連續性。上述措施,应进行2—3年。     

THE CLIMATE CHANGE AND FORESTRY OF HEILONGJI ANG PROVINCE IN 1990''''S

INTRODUCTIONIntheworldoftoday,theglobalclimatechangeanditsinfluenceonecologyhavebe-comeaveryimportantproblem,towhichmanyscientists,governnentleadersandordinarypcoplepaycloseattentionI1-'].Inl979,theWorldClimateResearchProgram(WCP)waslaiddowninthefirstworldclimatemeeting.lnl99(),thesecondworldclimatemeetingwasconvcl1edinGencva,andalltl1eexpertsagreedthattheglobalwarmlngwillbeextremelyseriousdisasterthananynatUralcalamityever.Attl1eMectingof"WorldEnvironmentandDevelopment,"holdinBrazil…     

甘肃地方苜蓿农家品种脯氨酸积累能力与抗旱性的研究

本文依据“脯氨酸维持积累时间”和“脯氨酸维持积累量”指标评介了四个甘肃地方苜蓿农家品种的抗旱能力。结果表明:敦煌苜蓿的抗旱能力高于会宁、秦安、灵台苜蓿,其中会宁苜蓿居二,灵台苜蓿抗旱性最差。这一抗旱排序与叶片相对含水量及气孔指标所得到的结果相一致。证明了“脯氨酸维持积累时间”和“脯氨酸维持积累量”可以作为首蓿抗旱性的鉴定指标。     

Airway hypersensitivity induced by Ascaris suum extract in New Zealand Romney sheep

Sheep from local farms with and without previous exposure to pigs were tested for their skin and airway responses to a commercial Ascaris suum antigen. There was an immediate reaction to intradermal injection of the antigen in 90% of 101 sheep. A bronchial provocation test by aerosol of the same antigen was undertaken on 43 of the sheep with a positive skin reaction. About 70% of sheep showed an immediate airway response to the antigen as an aerosol, reflected as a significant increase in airway resistance and/or decrease of dynamic lung compliance. The mean peak airway resistance and mean lowest dynamic lung compliance were 165% above and 61% below their baselines, respectively. No significant changes were recorded when the same animals were given an aerosol of phosphate buffered saline. Similarly, no correlation was found between the degree of skin reaction and the magnitude of bronchoconstriction (p>0.05). The sheep with previous exposure to pigs showed no significant differences in airway responses to antigen challenge, although they showed significantly greater skin reactions than those without exposure to pigs. These results indicate that the majority of Romney sheep in the Manawatu have a natural skin and airway sensitivity to A. suum antigen and may therefore be used as an animal model to study human airway hypersensitivity. The origin of this sensitivity has yet to be determined.     

东亚飞蝗蝗蝻抽样的研究

自五十年代以来,应用于东亚飞蝗蝗区估计蝗蝻种群密度的抽样方法,是样方为10平方尺的筒单随机抽样。本文是以抽样数、抽样消耗、相对精确度为标准,对三种抽样模型、三个抽样单位进行了比较。根据这些结果,我们提出了在当前蝗蝻密度较低的情况下,应采用样方为100平方尺的最适配额分层抽样。这种抽样方法在精确度方面可以高出现用的抽样方法2倍以上。而抽样时间消耗可相对节约一半以上。     

棉籽壳对黄萎病菌的抑菌作用和抑菌物质的分析

根据过去观察,棉籽壳有明显抑制黄萎病菌的作用。本试验初步证明这一抑菌物质具有丹宁类物质的某些特性。不同铃龄各部位的抑菌强度总趋势,与用高锰酸钾滴定法测得的丹宁类物质含量趋势一致,即不论大、中、小铃,感病及抗病品种,种壳的抑菌作用均大于胎座。初步认为种壳中较高浓度的丹宁类物质是种子内部带菌率极低的主要原因之一。纯丹宁在棉籽饼粉酒精洋莱培养基中的抑菌作用较供试的其它培养基小,说明此培养基用于种子带菌分离的优越性。棉花枯萎病菌对丹宁的耐受力显著高于黄萎病菌。     

Decomposition of calcium carbonate and organic carbon in the deep oceans

Simple mass-balance calculations indicate that in seawater the calcium variation (DeltaCa) correlates with the variation in the titration alkalinity (DeltaTA) and the variation in the total carbon dioxide (DeltasigmaCO(2)) or nitrate (DeltaNO(3)) according to the equations DeltaCa = 0.46288 DeltaTA + 0.074236 DeltasigmaCO(2) and DeltaCa = 0.5 DeltaTA + 0.53125 DeltaNO(3). The estimated values for DeltaCa from these equations, which agree with the values obtained from direct measurements, have been used to estimate the ratio of the in situ inorganic to organic carbon fluxes in the oceans. The precise vertical distribution of this ratio is shown for the first time.     

中国山羊品种资源及其遗传多样性研究

本文论述了中国山羊的起源、品种遗传资源及其遗传多样性的研究进展。最新调查 显示中国的山羊品种达50个,其中43个为地方品种,4个培育品种,3个引入品种,许多品种 具有独特的生产性能或适应能力。大量研究表明,我国山羊遗传多样性较为丰富。