光箨篌竹笋期生长规律初步研究

本文对光箨篌竹笋期的出笋规律、成竹规律以及竹笋的生长发育规律进行了研究。初步认为,光箨篌竹林分的母竹立竹度一般应保持在2500株/亩左右、Ⅰ～Ⅱ级母竹株数保持在40％以上时,才能保证林分的优质高产与稳产;抽枝成竹历期长短受竹笋笋级大小、出土早晚或立地环境条件的影响可相应延长或推迟2～4d左右,一般历时25d,竹笋开始抽枝成竹时的高度一般为5m左右;竹笋在生长发育高峰期明显受到气候因子的影响,尤其是对气温更为敏感。     

Comparison of an enzyme-linked immunospecific assay (ELISA) with the cold complement fixation test for the serodiagnosis of Brucella ovis infection

An enzyme-linked immunospecific assay (ELISA) for the serodiagnosis of Brucella ovis infection in sheep is described and compared with the cold complement fixation (CF) test. ELISA was performed in microtiter plates, using horse-radish peroxidase conjugated to anti-normal sheep serum globulins, and hydrogen peroxide plus o-phenylenediamine as substrate. A heated, cell-free B. ovis extract was used as antigen in both tests. ELISA was easier to perform, distinguished better between positive and negative sera, and did not need heat-inactivated sera.     

复合微生物肥料在无公害蔬菜栽培上的效应初报

施用复合微生物肥料使番茄产量提高 7.3 %～ 11.1% ,可溶性固形物含量提高 0 .9%～ 1.3 % ,硝酸盐含量降低 2 7.2 %～ 3 4 .8% ;苦瓜产量提高 10 .7%～ 16.1% ,硝酸盐含量降低 2 8.7%～ 3 6.1% ;菜薹产量提高 7.2 %～ 15.1% ,硝酸盐含量降低 55.6%～ 61.5%。各处理产品中的硝酸盐含量及有害元素的含量 ,均符合无公害蔬菜产品质量标准要求     

蜗牛液对不同果蔬病原菌的抑制及其细胞的溶解

蜗牛(Bradybaena kiangsinensis Martens)是我国的特有种群,它的腺体中含有多种生物活性物质。由于蜗牛在农业生产中具有一定的危害性,而忽视了其在生防中的作用。为探索蜗牛用于生防的可能性,作者对蜗牛提取液的抑菌和溶菌效果进行了研究。 1 材料与方法蜗牛液采用活体提取法,以无菌水作提取介质,用量为蜗牛量的30％,常温下浸提1h,然后过滤备用,以无菌水作提取液对照。抑菌试验采用含毒介质法,即取9ml PDA培     

永失我爱--祭爱犬丁丁

2005年2月底3月初的那段日子是我最背霉运，最不顺利的。3月7日中午，我忽然看到一张贴子，说有一窝（5头）小喜乐蒂犬待售，从来没有养过犬的我忽然间对此产生了浓厚的兴趣。这时丁丁就跃入我的眼帘：憨态可拘的他有着一双清澈的眼睛，努力睁得大大的试图将一切事物尽收眼底；一身柔软的小绒毛看上去活象一个小玩具，更让我对他注意的应该算是他又宽又通的鼻线，再加上小脑门上有一个好似菱形的小胎记。好，就是他了，我对自己说。     

宁南山区旱地紫花苜蓿土壤水分及产量动态研究

对宁南山区旱地紫花苜蓿土壤水分及产量动态进行了研究。结果表明,随苜蓿草龄的延长,土壤深层水分亏缺严重草地底层与中层对表层水分具有明显的补偿作用;伏秋降对水冬前土壤蓄水亦有重要作用;产量随草延长呈中间高两头低的态热,６－８年以后草地须及时更新。     

玉米价格高涨后的蛋鸡饲料解决方案

进入2006年以来,由于玉米价格持续走高,致使饲料生产成本提高。特别是近期小麦和玉米的倒挂价差越来越大,局部地区甚至达到160￣220元/t,使得部分饲料企业和养殖场开始在生产中用小麦替代玉米。当前,中原地区玉米质次价高,霉变严重,养殖户在当地要找到优质玉米很不容易,因此,多     

水稻田间育秧水肥药变量喷灌装置设计与试验

为解决南方水稻工厂化田间育秧水肥药人工管理作业中存在的灌溉均匀性差、化肥和农药浪费以及劳动强度大等问题,该研究设计了一种水稻田间育秧水肥药变量喷灌装置,阐述了水肥药变量喷灌装置总体结构和工作原理,进行了关键部件设计与试验;以可编程逻辑控制器（programmable logic controller,PLC）为控制核心,构建了注肥量在线调控及整机变量喷灌控制系统。采用Box-Behnken试验设计方法,对装置喷灌均匀性与主要影响因素进行试验研究,应用单目标优化方法对喷灌关键参数进行优化,并通过验证试验,得到最优参数组合为：干管入口水压0.20 MPa、球阀开度90°、喷头喷角80°,此时装置的喷灌均匀性为92.69%;构建了氯化钾肥液质量浓度与电导率（electrical conductance,EC）值的线性模型,开展了装置变量灌溉施肥性能试验,3种喷灌等级下各作业区的肥液EC值分别为1.65、1.66和1.68 mS/cm,平均喷灌强度分别为900.85、1092.04和1263.67 mm/h,施肥均匀系数分别为85.21%、87.86%和91.62%。采用水肥药变量喷灌装置开展水稻育秧田间管理试验,华航51常规稻和广8优165杂交稻的秧苗长势均匀度均高于95%,成毯性良好,各项素质指标满足机插作业要求。所设计的水肥药变量喷灌装置能够满足水稻田间育秧水肥药变量喷灌作业要求,对提高水稻工厂化田间育秧机械化水平、保证秧苗质量具有实际应用价值。     

Dihydroartemisinin enhances radiotherapy efficiency in H22 cell tumor-bearing mice by regulating PI3K/AKT signaling pathway

AIM To study the effect of dihydroartemisinin （DHA） on the radiotherapy efficiency in hepatocellular carcinoma H22 cell tumor-bearing mice and the role of phosphatidylinositol 3-kinase （PI3K）/protein kinase B （AKT） signaling pathway in this process. METHODS A model of H22 cell tumor-bearing mice was established. The mice was divided into model group, single radiotherapy group, 5-fluorouracil （5-FU） group, and low-, medium- and high-dose DHA groups. The body weight and tumor volume in each group were measured every other day. At the end of administration, blood was collected from the tail of the mice and the animals were killed by neck removal immediately. The synergistic effect of DHA on radiotherapy was determined, and tumor growth inhibitory rate was calculated. The degree of lymphocyte transformation and natural killer （NK） cell activity were measured by MTT, the serum levels of interleukin-2 （IL-2） and IL-4 were measured by ELISA, and the protein levels of PI3K, AKT and p-AKT were determined by Western blot. RESULTS The H22 cell tumor-bearing mouse model was successfully constructed. Compared with model group, the TGT₃ （tumor growth time to reach 3 times of volume） of single radiotherapy group was remarkably increased （P<0.05）, while tumor weight, lymphocyte transformation degree, NK cell activity, IL-2 and IL-4 levels, PI3K protein level and AKT phosphorylation level were remarkably decreased （P<0.05）. Compared with single radiotherapy group, TGT₃, EF （enhancement factor）, tumor inhibitory rate, lymphocyte transformation degree, NK cell activity, IL-2 level and IL-4 level were increased with the increase in DHA dose （P<0.05）, and the PI3K protein level and AKT phosphorylation level were decreased （P<0.05）. CONCLUSION DHA may enhance the immunity of tumor-bearing mice by inhibiting the activity of PI3K/AKT signaling pathway, thereby enhancing the efficacy of radiotherapy.     

谷物干燥仿人智能控制系统

针对具有非线性、大滞后和复杂性等特点的谷物干燥过程,研究了一种连续式谷物干燥机的仿人智能控制系统。利用出机粮食含水率偏差以及偏差的变化率作为控制器输入,控制器可根据含水率偏差的极值在线调整比例增益,进而输出排粮电动机期望转速。应用虚拟仪器开发平台LabVIEW和数据采集卡并结合传感器,设计出了该智能控制器的软件和硬件系统。试验结果基本符合仿人智能控制规则,表明该控制器的实时有效性较好。