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1.
栝楼核糖核酸酶(RNase TCS)对U碱基具有高度的专一性,在无脲、pH3.5、50℃时,它几乎都在-NP ↓ U-处裂解RNA.它与RNase T1,U2和有限的碱水解一起,可用于直接的酶法RNA序列分析.  相似文献   
2.
建立了从栝楼种籽大规模制备核糖体失活蛋白(TCK)的方法。进行了TCK与天花粉蛋白(TCS)性质比较研究。  相似文献   
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Clinical studies have demonstrated that SKI306X, a purified preparation of three medicinal plants, relieves joint pain and improves functionality in osteoarthritis patients. To study the biological action of SKI306X, bovine cartilage explants and human peripheral blood mononuclear cells (PBMC) were stimulated with IL-1β and lipopolysaccharide (LPS) respectively, in the presence or absence of SKI306X and its individual composites. All tested compounds inhibited dose-dependently IL-1β-induced proteoglycan release and nitric oxide production by cartilage, indicating cartilage protective activity. SKI306X and two of its compounds inhibited PGE2, TNF- and IL-1β production by LPS-stimulated PBMC, indicating anti-inflammatory activity. These results demonstrate that the biological effect of SKI306X is at least bipartite: (1) cartilage protective and (2) anti-inflammatory. The observed anti-inflammatory effects may provide an explanation for the outcome of the clinical studies. Long-term clinical trails are necessary to elucidate whether the in vitro cartilage protective activity results in disease-modifying effects.  相似文献   
5.
 研究了温室条件下紫外线-B(UV-B)辐射(0.029 J·m-2·s-1)和外施α-萘乙酸(α-NAA)(2 mg·L-1)相互作用对栝楼(Trichosanthes kirilowii)幼苗生长及蒸腾速率的影响。本实验设一个对照(T0)和3个处理:外施α-NAA(T1),增加UV-B辐射(T2),增加UV-B辐射并外施α-NAA(T3)。实验结果:增强UV-B辐射明显降低栝楼的株高及叶面积,根、茎、叶重均较对照低,因而总生物量也较对照低,干物质积累量减少。UV-B辐射增强,对栝楼植株含水量几乎无影响,但却明显增加叶气孔阻力,降低蒸腾速率。与对照(T0)相比,外施α-NAA(T1)明显增加株高及叶面积,根、茎、叶重均增加,因而单株总生物量较对照增加,但干物质积累量增幅不大,植株水分含量较对照略高;叶气孔阻力呈降低趋势,蒸腾速率呈增大趋势。在有UV-B辐射下外施α-NAA(T3),与T2相比,植株高度、叶重及叶面积降低趋势明显减轻,但根、茎生物量,单株总生物量及干物质积累量并无明显增加;叶气孔阻力降低,蒸腾速率增大。分析认为,栝楼幼苗根系发达,根冠比接近1,而UV-B辐射下补充α-NAA对根、茎影响小,同时本试验处理时间短(5周),表现为对生物量增加及干物质积累量的影响效果不明显,但株高、叶面积明显增加,且在一定程度上减小了叶的气孔阻力,增大了蒸腾速率。结果表明:UV-B辐射能对栝楼的根、茎、叶生物量及干物质积累量产生影响,同时也能引起栝楼叶气孔阻力增加及蒸腾速率降低,但若同时外施α-NAA,则这种影响有减轻的趋势。该结果暗示,α-NAA能增强栝楼幼苗对UV-B辐射的耐受能力,可能是弥补了UV-B辐射引起的IAA含量的降低,减少了内源ABA的积累,减轻叶片气孔阻力,增大蒸腾速率,促进了植株生长。  相似文献   
6.
聚乙二醇对栝楼种子萌发的影响   总被引:11,自引:0,他引:11  
针对栝楼籽萌发困难的问题,本试验采用聚乙二醇(PEG)对栝楼种子进行处理,结果表明:15%PEG浸种24h,可有效调节渗透水势,改变种子生理生化反应特性,并保持淀粉酶活性连续上升,使可溶性蛋白质含量明显提高,可见PEG在加速大分子动员和提高代谢能力方面发挥了作用,从而促进植物体的组织器官形态建成和生长发育;同时,PEG处理提高了过氧化物酶(POD)活性,降低了丙二醛(MDA)含量,减少了自由基积累,减轻了浸种吸涨对膜系统的损伤,降低了不利因素的影响,提高了种子活力。  相似文献   
7.
天花粉胰蛋白酶抑制剂基因的克隆及DNA序列分析   总被引:2,自引:1,他引:1  
从天花粉块茎中分离纯化的天花粉胰蛋白酶抑制剂TTI是目前已知的最小的蛋白酶抑制剂,它属于南瓜族蛋白酶抑制剂家族;由27个氨基酸残基组成,含三对二硫键。本文用PCR方法扩增一特异探针;结合传统的筛库方法,从天花粉cDNA基因库中筛选到含TTI基因的克隆,经序列测定,得到了TTI的cDNA全序列。其读框编码区编码的是一个由65个氨基酸组成的Pre-Pro-TTI,Pre与Pro分别含有24个和14个氨基酸。由cDNA序列推论的氨基酸序列和已测定的氨基酸序列完全相同。  相似文献   
8.
The impact of UV-B radiation on endogenous hormones in plants has recently drawn attention from researchers. The mechanism for reduced stem elongation by UV-B might be due to changes in the phytohormone levels, especially IAA, which plays a role in stem elongation. In this study, effects of UV-B radiation on Trichosanthes kirilowii Maxim (T. kirilowii) seedlings in greenhouse-grown plants were investigated. The results indicated that: (1) In comparison to controls, exposure to 0.029 Jm?2 s?1. UV-B radiation led to accumulation of endogenous abscisic acid (ABA) and zeatinriboside (ZR) in the plant contents, and decreased contents of endogenous indole-3-acetic acid (IAA) and gibberellic acid (GA1/3). Exposure to UV-B radiation reduced the height and leaf area of plants. As a result, total biomass (plant dry weight) was lower. (2) In comparison to controls, addition of 2 mg l?1 α-naphthaleneacetic acid (α-NAA) slightly increased the contents of IAA, GA1/3 and ZR, and decreased the content of ABA in leaves. This addition of α-NAA significantly increased plant height and leaf area, but only slightly increased total biomass. (3) Addition of α-NAA to UV-B-exposed plants: increased the content of endogenous IAA, GA1/3 and ZR; decreased accumulation of endogenous ABA; and increased plant height and leaf area in comparison to plants that only were exposed to UV-B. Moreover, total biomass increased slightly. This suggests that addition of α-NAA may compensate to a certain extent for the lack of IAA resulting from UV-B radiation; it also increases the content of GA1/3 and ZR, decreases the accumulation of ABA, and promotes the growth of plants.  相似文献   
9.
We measured diurnal changes in photosynthetic rate, transpiration rate, stomatal conductance and water use efficiency in three species of herbaceous climbing plants (Luffa cylindrica, Trichosanthes kirilowii and Dioscorea opposita) exposed to two intensities of UV-B radiation: 3.0 μw cm?2 (R1) and 8.0 μw cm?2 UV-B (R2) radiation under ambient growth conditions. Responses differed per species and per treatment. In Luffa all values increased compared to the Control in both treatments, except for stomatal conductance in R2. In Trichosanthes photosynthetic rates and water use efficiency increased, while the transpiration rates decreased under both treatments, and stomatal conductance was lower in R1. In Dioscorea photosynthetic rates and water use efficiency decreased under both treatments, while the transpiration rates and stomatal conductance increased. The results suggested that to some extent increased UV-B radiation was beneficial to the growth of L. cylindrica and T. kirilowii, but detrimental to D. opposita.  相似文献   
10.
雌雄栝楼的组织培养研究   总被引:2,自引:0,他引:2  
对雌雄栝楼(Trlctmsanthes kirilowii Maxim)分别进行组织培养的研究结果表明:在雌雄栝楼组织培养过程中,愈伤组织的诱导和分化适宜的培养基均存在性别差异。愈伤组织诱导的适宜培养基分别是,雌性栝楼培养基为MS+NAA0.5mg/L+IBA0.5mg/L+6-BA1.5mg/L;雄性栝楼培养基为MS+NAA0.1mg/L+IBA0.5mg/L+6-BA0.5mg/L和MS+NAA0.1mg/L+IBA1.0mg/L+6-BA1.0mg/L。愈伤组织分化的适宜培养基分别是,雌性栝楼培养基为MS+NAA0.1mg/L+IBA0.4mg/L+6-BA1.2mg/L;雄性栝楼培养基为MS+NAA0.3ms/L+IBA0.2mg/L+6-BA0.8mg/L;雌雄栝楼无根苗生根的适宜培养基均为MS+NAA0.1mg/L。  相似文献   
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