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81.
82.
黄瓜器官特异蛋白的研究 总被引:14,自引:0,他引:14
利用 SDS单向电泳对黄瓜 ( Cucumissativus L .)的根、茎、叶、花萼、花冠、雄蕊、花柱和子房的可溶性蛋白进行了分析和比较。检测到花冠中的 2 3.5 k D和 33.0 k D,雄蕊中的 1 8.8k D、2 8.5 k D、31 .0 k D、37.0 k D和 39.0 k D,花柱中的 4 5 .0 k D及子房中的 32 .5 k D蛋白 ,分别为各自器官中的器官特异蛋白质。对花冠、雄蕊、花柱和子房的可溶性蛋白的 IEF- SDS双向电泳分析也确定了相应于 SDS单向电泳上特异蛋白带的蛋白质斑点。而且相应于 SDS单向电泳上的一条带 ,在 IEF- SDS双向电泳上可能是一个以上的分子量相同而等电点不同的几个蛋白质斑点。各种器官的蛋白质含量以雄蕊为最高、花萼为最低。 相似文献
83.
Transmission Efficiency of Cucumber green mottle mosaic virus via Seeds,Soil, Pruning and Irrigation Water 下载免费PDF全文
Cucumber green mottle mosaic virus (CGMMV; genus Tobamovirus) infects frequently the grafted watermelon and is widely distributed in China. Investigating the transmission modes and their efficiency is urgently needed to understand the factors contributing to the epidemiology of this viral disease. In the present study, we found that the occurrence of CGMMV in a bottle gourd seed production base reached 100%, while the contamination rate and transmission rate were 100 and 0.92%, respectively. The bottle gourd plants showed obvious mottle symptom on leaves starting 36 days after seed sowing. The long latent period of CGMMV in seedlings implies a potential risk to use contaminated seeds in the production of grafted watermelon. This virus could overwinter in soil with debris of infected plants, and the infection rate of CGMMV from contaminated soils was 10.30%. CGMMV could be transmitted from infected watermelon plants to healthy ones by pruning at least to the ninth plant during the whole growing season. The transmission distance was 1.87 m by drip irrigation and 2.31 m by flow irrigation. This study suggested that contaminated seeds, contaminated soil, pruning and irrigation could transmit CGMMV at different efficiency, and all contribute to the epidemiology of CGMMV. 相似文献
84.
J. E. Staub D. Globerson A. Genizi 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1989,78(1):143-151
Summary Reciprocal matings were made between two Cucumis sativus var. sativus L. inbred lines (WI 1606 and WI 2808) and two var. hardwickii (Royle) Alef. accessions (PI 215589 and PI 183967). Each case produced a series of reciprocal F1, F2, and BC1 and BC2 progenies which were used to evaluate seed dormancy in var. hardwickii. Under controlled conditions (25°±1°C and 85%±5% RH; 12 h fluorescent light, 30 mol s–1 m–2), no seed dormancy was observed in the var. sativus inbred lines 36 days following seed extraction from fruit. With rare exception, var. hardwickii accessions were dormant for at least 60 days. Seed dormancy in the F1 was absent 36 days post extraction, indicating that dormancy in var. hardwickii is conditioned by recessive genes present. Seed of some F1 progeny germinated between 36 and 50 days post-extraction, indicating the presence of transient dormancy or the more variable expression of the dormancy of var. hardwickii. No significant reciprocal differences in either germination rate or percentage were detected in either of the F1 and F2 progeny sets, suggesting lack of cytoplasmic or maternal control over these traits. It was estimated that three to seven factors or loci are involved with the expression of this trait depending on the method of calculation, and that a complex interaction between embryonic and non-embryonic tissue exists. Least square estimates indicate that both additive and dominance effects were important in the expression of dormancy. Comparison of theoretical geometric and arithmetic F2 means to observed F2 means also suggests that non-additive gene action contributes substantially to the observed variation. Broad-sense heritability ranged between 78 and 95%. 相似文献
85.
在光照下对黄瓜(Cucuntis sativus L.)离体子叶圆片和幼苗分别使用10~(-6)mol/l 与10~(-4)mol/l ABA 处理,有防御低温伤害的作用,表现为降低子叶圆片的电解质渗漏,阻抑幼苗子叶的谷胱甘肽含量的下降和膜脂过氧化产物丙二醛(MDA)的累积,减缓叶片的光合作用的下降和叶绿素荧光的猝灭,提高幼苗的存活率。但这种作用可被黑暗和光合抑制剂(DCMU)所限制。 相似文献
86.
黄瓜果实贮藏过程中某些形态,生化变化及其控制 总被引:1,自引:0,他引:1
黄瓜果实采后贮藏过程中,随着其花端部位的种子的不断发育,中部及茎端逐渐萎缩变糠,花端膨大(称为“大头现象”)。花端胎座组织中蛋白质、DNA、RNA 及干重等都随着时间延长呈增加趋势,而中部组织的上述物质的含量则急剧下降。贮藏20天,中部果皮及胎座组织中 DNase 活性分别增加了5和7倍,RNase 活性增加了5和6倍,这两种酶活性在花端组织中则几无变化。实验发现用 BA+GA,处理果实对于延迟花端膨大及中部萎缩有效,并能显著延缓果实叶绿素含量的降低。未授粉果实在贮藏过程中不出现“大头现象”,其蛋白质等物质的含量在果实各部位几乎以相同的速度降低。 相似文献
87.
大白菜和黄瓜原生质体电击基因转移的研究 总被引:1,自引:0,他引:1
本文以钙黄素、FITC-IgG 和溴乙锭-质粒 DNA 为荧光标记物,研究了电脉冲引起大白菜和黄瓜原生质体质膜通透性的改变及其动力学过程以及脉冲电学参数(脉冲幅值、个数、宽度)对原生质体成活率和外源物质导入率的影响。通过电击法成功地将外源 CAT(氯霉素乙酰转移酶)基因导入黄瓜原生质体并实现瞬间表达。45℃热激预处理原生质体有效地促进了CAT 基因的电击转移。 相似文献
88.
Cellular subsets of the milky spots in the human greater omentum 总被引:11,自引:0,他引:11
Masataka Shimotsuma Toshio Takahashi Mitsuhiro Kawata Kazimierz Dux 《Cell and tissue research》1991,264(3):599-601
Summary The cellular composition of the human milky spots was investigated on surgically removed specimens of the greater omentum of three 8-month-old infants operated on for neuroblastoma. Monoclonal antibodies and immunohistochemical methods for recognition of macrophages, B-lymphocytes and T-lymphocytes and toluidine-blue staining for mast cells were used. The mean number of cells in one milky spot amounted to 570±33. This cell population was composed of 47.5% macrophages, 29.1% B-lymphocytes, 11.7% T-lymphocytes and 6.1% mast cells. Since inflammation was absent in the material investigated, the numerical data found in the present paper could be regarded as representative cell levels of normal milky spots. 相似文献
89.
90.
不同基因型砧木嫁接黄瓜结瓜盛期光合特性的比较 总被引:2,自引:0,他引:2
采用CIRAS-Ⅱ型便携式光合作用系统,对黑籽南瓜和新培育的白籽南瓜A22种不同基因型砧木嫁接黄瓜结瓜盛期的光合特性进行比较。结果表明:在结瓜盛期,2种砧木嫁接黄瓜不同叶位的叶片净光合速率均有一定差异,其中A2嫁接黄瓜中部和下部叶片的净光舍速率显著高于黑籽南瓜嫁接的黄瓜。A2与黑籽南瓜相比其嫁接黄瓜利用光能范围较广且光饱和时净光合速率、RuBP最大再生速率和表观量子效率分别高出黑籽南瓜嫁接的黄瓜23.2%、12.6%和8.2%。2种砧木嫁接的黄瓜CO2饱和点与羧化效率均相近,CO2补偿点A2低于黑籽南瓜嫁接的黄瓜。A2嫁接黄瓜叶片叶绿素a、b及叶绿素总量均明显高于黑籽南瓜嫁接的黄瓜,可溶性蛋白含量与黑籽南瓜嫁接的黄瓜差异不显著。A2嫁接黄瓜的雌花节率和平均单株产量分别高出黑籽南瓜嫁接的黄瓜25.2%和29.4%,A2嫁接黄瓜果实可溶性糖、可溶性蛋白和VC含量分别高出黑籽南瓜嫁接的黄瓜6.3%、15,2%和15.4%。 相似文献