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21.
苏南丘陵区秋播苜蓿适用伴生作物筛选试验 总被引:3,自引:0,他引:3
为解决苏南丘陵区苜蓿苗期的杂草问题,从保护播种入手,在多年生黑麦草、一年生黑麦草、黑麦、小黑麦四种作物共五个品种中寻找适宜的伴生作物.通过对产量、株高、杂草率等多个指标测定分析,筛选出中新830小黑麦、赣选一号黑麦草适于用作苜蓿播种的伴生作物,同时获得两个苜蓿存活率最高的处理:苜蓿(15kg/hm^2)+中新830小黑麦(150kg/hm^2)撒播及苜蓿(18 kg/hm^2)+中新830小黑麦(250kg/hm^2)30cm条播.试验还表明撒播方式下,苜蓿播量与其竞争力不成正比。 相似文献
22.
AIM:To investigate the expression of Th1-typed cytokine IFN-γ and Th2-typed cytokine IL-4 on T lymphocytes that infiltrate in nasal polyps for searching the pathogenesis of nasal polyps. METHODS:Nasal polyps tissue samples and peripheral blood were obtained from 21 patients. Normal human inferior turbinate mucosa and peripheral blood were obtained as well. Flow cytometry was adopted to detect the expression of IFN-γ and IL-4 of T lymphocytes. RESULTS: Th cytokines were rarely detected in inferior turbinate from normal human. Nasal polyps tissue consisted of abundant T lymphocytes. The expression of IL-4 and IFN-γ increased in peripheral blood from patients compared with normal human (P<0.05). The expression of IL-4 increased but the expression of IFN-γ decreased in nasal polyps compared with that of peripheral blood from the same patient (P<0.05). CONCLUSION:There were generous of T lymphocytes infiltrating in nasal polyps. There was abnormal immune status in the local nasal mucosa from the patients, and the predomination of Th cytokine secretion changed compared with peripheral blood from the same patients, which resulted in the change of microenvironment of nasal mucosa and possibly close related to the formation of nasal polyps. 相似文献
23.
莲子草假隔链格孢的寄主范围及对空心莲子草的控制作用 总被引:18,自引:0,他引:18
空心莲子草(Alteranthera philoxeroides)由于具有繁殖迅速、适应性强等特点,于20世纪50年代被引人我国江苏和浙江等地作为牲畜饲料植物栽培,随后相继传人全国各地并引起危害,成为我国大部分省区旱地和水域的恶性杂草之一。其微生物防治目前仍处于生物防治物的调查筛选阶段,已发现的病原真菌有假隔链格孢菌(Nimbya alternantherae)、炭疽菌(Colletotrichum gloeosporioides)、立枯丝核菌(Rhizoctonia solani)及链格孢(Alternaria sp.)等。 相似文献
24.
Cytochrome P450 monoxygenase converts arachionic acid to four epoxyeicosatrienoic acid regiosomes: 5, 6-EET (epoxyeicosatrienoic acid); 8, 9-EET; 11, 12-EET and 14, 15-EET. Recent studies show that EETs are involved in signal transduction. EETs open Ca2+-sensit ive K+ channel and inhibit Na+ channel, Ca2+-sensitive Cl- channel and so on. What is more, EETs have been demonstrated to activate PP60c-src and initiate a tyrosine kinase cascade that mediates mitogenic effects. 相似文献
25.
AIM: To investigate the effect of berberine (Ber) on the activation and proliferation of T lymphocytes and its mechanism of action. METHODS: Whole peripheral blood from normal subjects was stimulated with phytohemagglutinin (PHA) or phorbol ester (PDB) plus ionomycin (Ion) and the expression levels of CD69 and CD25 were evaluated with flow cytometry after the staining with appropriate fluorescent monoclonal antibody. The distribution of cell cycles was analyzed by propidium iodide staining and dead cells by 7-aminoactinomycin live staining. RESULTS: 100 μmol/L and 50 μmol/L of Ber had significant inhibition of the expression of CD69 on T cells stimulated with PDB plus Ion or PHA, while effect of 25 μmol/L Ber was not significant. And as time of action extended, the extent of inhibition decreased. For the expression of CD25, Ber at the concentrations as above all exerted significant inhibitory effect in a dose-dependent manner. Moreover, Ber could block lymphocytes cell cycle progression from G0/G1 phase to S and G2/M phase without phase specificity. Besides, live staining analysis revealed that Ber did not have significant cytotoxicity on lymphocytes. CONCLUSIONS: Ber significantly inhibits the expression of early and mid activation antigens of T cells and also blocks the progression of lymphocytes cell cycles. These results suggest that Ber exerts immunosuppression effect through inhibiting the activation and proliferation of T cells. 相似文献
26.
AIM: To study the electrophysiological characteristics of ion channels of stem cell derived cardiomyocytes(SCDC) of mouse. METHODS: Embryonic stem cells of D3 line(ES-D3) were cultured on the MEF feeder layer with BRL conditioned medium, and fetal mouse heart cells(FMHC)were cultured in vitro. Then ES-D3 cells were induced to differentiate into many kinds of cells. SCDC were harvested on day 12 after differentiation initiating and identified by electro-microscope and immunocytochemistry. SCDC and FMHC were prepared for the patch-clamp research. Sodium and calcium currents together were elicited and compared between SCDC and FMHC. RESULTS: The current characteristics of sodium and calcium channels of SCDC were very similar to FMHC. CONCLUSION: The functional expression of ion channels occurred during ES-D3 cells differentiation and the electrophysiological characteristics of sodium and calcium channels of SCDC are very similar to FMHC. 相似文献
27.
28.
研究了两种β-环糊精的衍生物甲基-β-环糊精(MCD)和羟丙基-β-环糊精(HPCD)对甲基对硫磷的增溶作用和对紫外光降解的影响。结果表明:MCD和HPCD能增强甲基对硫磷的水溶性,在25℃下,20 g/L的MCD和HPCD溶液中,甲基对硫磷溶解度比在纯水中分别提高了21.91和17.92倍;另外,3 g/L、6 g/L MCD和HPCD分别处理的甲基对硫磷,其光降解速率分别加快了4.87~6.85倍。增溶作用和光敏效应主要是由于MCD和HPCD与甲基对硫磷形成包合物引起的。 相似文献
29.
热胁迫对辣椒花柱细胞中Ca2+ 分布的影响 总被引:5,自引:0,他引:5
用焦锑酸钾沉淀法研究了热胁迫对辣椒开花前后柱头和花柱细胞中Ca2+分布的影响。结果表明: 常温下Ca2+ 分布在柱头细胞表面、花柱引导组织细胞间隙等质外体系统中, 且在花粉管上呈先增加后减少的规律性变化; 热胁迫后, 除细胞间隙等质外体系统外, 细胞质和细胞核中也出现Ca2+, 花柱引导组织中通过的花粉管发生扭曲、变形, 这可能与Ca2+ 的异常分布有关。 相似文献
30.
武夷菌素对番茄灰霉菌的抑制作用及对番茄抗病性相关酶活性的影响 总被引:3,自引:0,他引:3
采用凹陷载玻片法测定了武夷菌素对番茄灰霉菌分生孢子萌发的抑制作用,在离体番茄叶片上测定了被武夷菌素处理后的番茄灰霉菌菌丝和分生孢子致病性的变化以及武夷菌素对番茄幼苗体内抗病性相关酶活性的影响。结果表明:武夷菌素对番茄灰霉菌的分生孢子有较强的抑制作用,其EC50为14.1μg/mL。浓度为100μg/mL的武夷菌素可完全抑制孢子的萌发。武夷菌素能使灰霉菌菌丝和分生孢子的致病性明显下降,同时还能诱导番茄体内抗病性相关酶(SOD、POD、PPO、PAL)活性的增强,提高番茄幼苗的抗病性。 相似文献