Flow cytometric evaluation of canine bone marrow differential cell counts

Abstract: Three flow cytometric techniques were evaluated for determination of differential cell counts on canine clinical bone marrow specimens. Techniques included staining bone marrow specimens with 2'7'-dichlo-rofluorescein (DCF) or 3,3'-dihexyloxacarbocyanine iodide (DiOC6) and evaluation of forward-angle light scatter vs. side-angle light scatter plots. Flow cytometric evaluation of bone marrow cells stained with DCF failed to separate bone marrow cells into distinct cell populations. Staining with DiOC6 resulted in separation of bone marrow cells into populations of mature and immature erythroid cells, mature and immature myeloid cells, and lymphocytes. The scatter plot method resulted in identification of mature and immature erythroid cells, immature myeloid cells, metamyelocytes, and bands and segmenters. Lymphocytes could not be differentiated from mature erythroid cells by the scatter plot method. When the results of the DiOC6 method and the scatter plot method were compared with manual bone marrow differential cell counts, the scatter plot method had more similar mean values and higher correlation coefficients. The scatter plot method has the potential of providing rapid semiquantitative assessment of bone marrow differential cell counts in dogs for specimens that contain low numbers of lymphocytes.     

灰色关联度分析法对不同处理下草坪质量的综合评判

应用灰色系统理论对不同施氮量和施肥次数处理下的草坪质量进行了分析与评判.结果表明:施用氮肥是提高草坪质量的重要措施,在35 g/m2施量水平下,草坪质量与施肥量呈正相关(R2＞0.9100);施肥次数对其影响不显著.建议在实践中施肥量以25 g/m2为宜.     

Sap flow in papaya plants: Laboratory calibrations and relationships with gas exchanges under field conditions

In papaya plants a study to quantify the water flow through the trunk is important for to promote a good water management in commercial orchard. The objective was to study the relationship between water flow through the trunk and temperature measurements determined by probes inserted in the papaya plant stem in laboratory. In addition, was possible to study the relationship between sap flow and instantaneous gas exchange in field conditions. We constructed an instrument that maintained a stable water flux through a 0.30 m stem section with a constant pressure, simulating the xylem sap flow through the stem. Water flux was adjusted by varying pressure of water in the stem section. The mathematical model used to fit the relation between K (Granier heat coefficient) values and sap flow density was the exponential model: u = 0.5511 × K^1.9104. Field studies was conducted in a commercial orchard located in North of the State of Rio de Janeiro, with 12 plants in October 2002, and eight plants in January 2003. We verified that instantaneous transpiration, measured by a portable system of gas exchange (porometry), presented a good (R² = 0.75) positive relationship with xylem sap flow. Estimates of papaya sap flow can be obtained by scaling portable photosynthesis system measurements with exposed leaves, however the relationship is non-linear in higher instantaneous transpiration rates. The causes of the non-linear relationship in higher transpiration are discussed. In addition, was possible to obtain a good (R² = 0.76) relationship between net photosynthesis rate and xylem sap flow in papaya field-grown.     

DETECTION OF PORTAL BLOOD FLOW USING PER-RECTAL 99mTc-PERTECHNETATE SCINTIGRAPHY IN NORMAL CATS

This study reports data obtained from per-rectal ^99mTc-pertechnetate portal scintigraphy in normal cats. It examines the effects of chemical restraint and the methods employed in defining regions of interest (ROIs) on the shunt index derived from this data. Six normal cats were used for the study; all six were chemically restrained for imaging using propofol and later four of them were manually restrained for comparison. Portal blood flow was studied and the mean shunt index was found to be 5.9%± 3.9 when ROIs were operator defined and 9.2%± 4.4 when ROIs were defined using an isocontour program. In cats that were restrained using propofol and operator defined ROIs, the mean value for the time between detection of radioactivity in the liver and in the heart was 14 ± 1 seconds.     

黄瓜自交系低温弱光耐受性快速筛选平台的建立

黄瓜对低温和弱光的耐受性是两个相对独立的性状,需要单独进行评价.设计了以叶面积增长量为主要性状指标的弱光(或弱光 偏低温)耐受性的评价指标体系和以冷害指数作为临界低温耐受性评价指标的快速筛选体系,两者可复合实施.     

梨树干木质部液流速度径向分布特征

采用热脉冲法对梨树树干液流速度径向变化规律进行了系统研究。结果表明：①梨树树干木质部不同深度液流速度在生长旺盛的晴天、阴天和小雨天呈单峰或双峰曲线;而在中到暴雨天、9月底小雨天和即将休眠的10月底晴天,各深度液流速度日变化不规则。②树干同一深度液流速度日峰值、日均值、日变幅在晴天、阴天、小雨和中到暴雨天的比例相同,约为5:4:3:2;不同方向液流速度径向变幅在以上天气的比例为6:4:3:2,而同一深度液流速度最小值在不同天气时差异不大。③梨树树干不同深度白天液流速度和液流速度径向变幅分别在5—7月、8—9月相近,8—9月、10月同一深度液流速度分别是5—7月的50%～60%和33%～50%;5—7月、8—9月和10月液流速度径向变幅比约为5:2:1。液流速度峰值主要出现在形成层至髓0.12～0.29的位置。④晚上液流速度径向季节变化趋势与相应的白天相似,整个生长季晚上液流速度和径向变幅分别为白天的43%±1%和29%±7%。     

树干径向变化对茎液流以及气象因子的响应

应用改进的SF-L型热扩散式树液流测定装置和DC型植物生长测量仪,结合北京2007年6-10月的气象数据,探讨了北京山区油松、侧柏树干茎周长动态因素与液流速率和气象因子之间的相关关系,并运用树木径向变化周期分段法将树木径向生长量从径向变化过程中分离开,结果表明:(1)油松、侧柏茎周长变化与液流速率的关系显著(P<0.01),油松为正相关,侧柏为负相关.(2)空气水汽压亏缺、日温差、空气湿度和日照时数与油松、侧柏茎周长变化关系显著,但在回归拟合过程中侧柏的解释因子只有空气水汽压亏缺和日平均风速,且解释程度比较低(0.356).(3)油松、侧柏茎周长生长量的拟合水平较高,且影响气象因子相同,侧柏的液流速率也成为解释因子之一.水汽压亏缺、空气温湿度、日照时数、土壤水势和风速对树木的生长起到决定性的作用.     

5种杀虫剂超低容量液剂对玉米田草地贪夜蛾的防治效果

草地贪夜蛾是新入侵我国的迁飞性重大害虫,为害玉米的心叶、生长点及雄穗等,能引起严重的损伤、烂心、授粉不良等,导致玉米减产甚至绝产。本文评价了5种杀虫剂超低容量液剂通过低容量喷雾对玉米田草地贪夜蛾的防治效果。结果表明,在相同的原药成本下,6%甲维·茚虫威超低容量液剂和1%甲氨基阿维菌素苯甲酸盐超低容量液剂具有优异的保叶效果和杀虫效果,5%氯虫苯甲酰胺超低容量液剂在较低的用量下(有效用量1 g/667m~2)具有良好的保叶和杀虫效果,3%呋虫胺超低容量液剂对草地贪夜蛾幼虫基本无效,但有一定的保叶效果。     

低温弱光对苗期紫花苜蓿根颈生理特性的影响

以秋眠级不同的2个紫花苜蓿Medicago sativa品种(巨人201和WL414)为试验材料,研究了其在低温(0~5℃和5~10℃)与弱光[50和100μmol/(m2.s)]互作处理条件下的生理响应。结果表明:紫花苜蓿根颈在低温弱光胁迫下启动了自身应激机制,对逆境胁迫做出了适应性反应,相同弱光条件下,低温0~5℃比5~10℃对根颈的影响显著,过氧化物酶活性上升幅度较小,而超氧化物歧化酶活性的下降和丙二醛含量的增加幅度均较大;相同低温处理,弱光50μmol/(m2.s)处理对根颈生理指标影响更为显著,过氧化物酶活性上升、超氧化物歧化酶活性下降和丙二醛含量增加幅度大于弱光100μmol/(m2.s)处理;巨人201各项指标的变化都优于WL414,表明巨人201抗寒耐弱光能力都可能优于WL414。     

斑背大尾莺汉口亚种(Locustella pryeri sinensis)遗传多样性及种群结构研究

采用线粒体控制区（807bp）序列分析对中国境内斑背大尾驾3个繁殖种群及1个越冬种群的遗传多样性及种群遗传结构,结果表明：斑背大尾莺的单倍型歧义度（Hd）为0.759&#177;0.056,核苷酸多样性较（π）为0.002。三个地理种群的FST值以及繁殖种群同越冬种群之间的ΦST值表明不同地理单元之间无显著遗传分化。对不同单倍型的聚类分析（UPGMA）结果以及网络图（Network picture）结果也支持不同种群之间无显著分化。分子变异分析 （AMOVA）显示斑背大尾莺汉口亚种不同地理种群间遗传差异不大,98.5%的差异源自种群内部,仅1.5%源自种群间。中性检验结果Fu’sFS值为负值,错配分布分析结果呈单峰,表明斑背大尾驾在我国的进化史经历了种群扩张。这一假设也得到Tajima’D检验和Fu’s检验结果的支持（D=-1.80,p=0.02;Fs=-22.11,p=0.001）,该扩张大约发生在28,700年前。