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101.
102.
三唑酮对黄瓜子叶抗氧化酶活力的影响 总被引:6,自引:2,他引:4
黄瓜子叶衰老过程中超氧物歧化酶(SOD)、过氧化氢酶(CAT)和抗坏血酸-过氧化物酶(ASA-POD)活性降低,而过氧化物酶(POD)活性升高。20mg/L三唑酮右明显提高SOD,ASA-POD,CAT活性,抑制POD活性升高。膜脂过氧化产物丙二醛(MDA)含量在叶片衰老过程中提高,三唑酮可降低MDA含量。表明三唑酮减轻脂氧化程度,延缓了叶片的衰老。 相似文献
103.
104.
Ewa Hanus-Fajerska Maria Lech Anna Pindel Kazimierz Miczyński 《Acta Physiologiae Plantarum》2000,22(3):317-324
Protocols elaborated with the objective of achieving valuable material for selection procedure of variants with virusresistance
traits in tomato genotypes are presented. Preliminary results are demonstrated in the domain of testing for variability in
somaclones obtained through indirect adventitous organogenesis initiated on leaf explants of cultivated tomato (Lycopersicon esculentum Mill.). Somaclones were grown in greenhouse conditions and variation of their symptoms upon infection with tomato mosaic
(ToMV) or cucumber mosaic (CMV) respectively was observed. Tests for resistance to the local isolates of the above cited viruses
were performed using enzyme linked immunosorbent assay and back inoculation onto diagnostic plants. Screening data are presented.
Desirable variants were selected from cultivars ‘Moneymaker’, ‘Potentat’ and ‘Rutgers’. Some of the ‘Moneymaker’ somaclones
exhibited increased tolerance to cucumber mosaic virus, a few seemed to be even fully resistant though most were susceptible
as donor plants. The most favourable somaclonal lines are actually further tested and monitored for changes in horticultural
characteristics. The described procedure of searching for resistance trait in specific pathogen-free (SPF) plants regenerated
from infected tissue looks promising and thus can serve as aid in attaining appropriate objectives of breeding programme.
Additionaly experiments were initiated to obtain somaclones from cultivars ‘Beta’, ‘Krakus’ and Stevens Rodade hybrid via
regeneration of isolated protoplasts. To this end the callus stage was obtained from all donors. 相似文献
105.
The cucumber cotyledon expansion test was used as a model system to study a possible relationship between cytokinin and polyamines.
When kinetin was applied to excised cotyledons incubated in the dark it caused a marked increase in the activity of arginine
decarboxylase. As a result of ADC action, putrescine content also rose markedly, whereas the level of spermidine and spermine
decreased. However, inhibition of putrescine biosynthesis with D-arginine did not affect cytokinin promotion growth. Applied
alone, putrescine had no significant effect on growth. These results indicate that the large increase in putrescine content
that derives from cytokinin treatment cotyledons is not essential for cytokinin-induced expansion of cotyledons. Addition
of K+ and Ca2+ ions to the cotyledons incubated with cytokinin caused a marked reduction in the putrescine level and ADC activity.
The higher level of putrescine (35 %) and spermine (62 %) bound to chromatin and the large increase (174 %) in spermidine
content bound to ribosomes which derive from cytokinintreated cotyledons in relation to literature data can indicate that
these polyamines may play an important role in gene expression during cytokinin-stimulated expansion of cucumber cotyledons.
The inhibition of cytokinin effect, viz. enlargement of the cotyledons by inhibitors of spermidine biosynthesis, additionally suggessted a possible involvement of
polyamines in cytokinin action. 相似文献
106.
Scanning electron microscope and energy-dispersive X-ray analysis were used to study the tissular distributions of elements
Na, Mg, Cl, K, Ca, Mn, and Fe in leaves of cucumber seedlings in the absence or presence of La3+. The results showed that the atomic percentages of Na, Mg, Cl, K, and Ca were basically reduced and those of Mn and Fe were
increased in the presence of La3+; in addition, at 0.02 mM La3+, the reduced or increased degrees were higher than those at 2.0 mM La3+. The effects of La3+ on ion absorption were similar to those of Ca2+, suggesting that the rare earth element lanthanum affects the plant physiological mechanism by regulating the Ca2+ level in plant cell. 相似文献
107.
Holy J 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》2000,127(4):491-504
The presence and organization of intermediate filament (IF) proteins in petaloid coelomocytes from two species of echinoderms, the sea urchin Strongylocentrotus droebachiensis and the sea cucumber Cucumaria frondosa, were studied. Two monoclonal antibodies (IFA and Ah6) and one polyclonal antibody (W3-1) that together recognize invertebrate as well as vertebrate IF proteins were used to probe coelomocytes by immunofluorescence and immunoblotting methods. All three antibodies cross-reacted with a single Mr 68 000 sea urchin lamin, as well as two putative lamin isoforms of approximately Mr 70 000 and 68 000 in sea cucumber coelomocytes. Both IFA and Ah6 labeled granular material in the cytoplasm of sea urchin coelomocytes; by contrast, IFA labeling revealed a striking network of reticular material irregularly arrayed within the central regions of the sea cucumber coelomocyte cytoplasm. In addition, foci of Ah6-positive material were present in coelomocyte nuclei from both species. Comparison of immunoblotting patterns among whole cell and isolated nuclear preparations suggest that the cytoplasmic IF-like material is composed of Mr 46 000 and 58 000 polypeptides, while Mr 215 000 and 185 000 proteins are candidates for the immunoreactive nuclear foci. Further study of the functions of these non-filamentous arrays of IF proteins may furnish valuable insights into the evolution of IF function within vertebrate cells, particularly with respect to certain cytoplasmic and nuclear regulatory functions with which IF proteins have been speculated to be involved. 相似文献
108.
用黄瓜为材料 ,研究了草酸对植物根切段还原Fe(Ⅲ )EDTA的促进作用。在 2~ 14mmol/L范围内随着草酸浓度的加大 ,其促进作用不断提高 ;在 4h内随着反应时间的推移 ,Fe(Ⅲ )EDTA的还原量成线性上升趋势。进一步用完整根、粗酶提取液和提纯的质膜证明 :促进作用并非草酸本身作为电子供体直接或间接地加速了铁还原反应 ,而是形成的草酸铁螯合态是根中铁还原酶更有效的底物。整体根还原草酸铁的活力和质膜铁还原酶催化草酸铁的效率 (Vmax/Km)都远大于还原柠檬酸铁和Fe (Ⅲ )EDTA的活力和效率 相似文献
109.
黄瓜幼苗子叶在低温下的光抑制及其恢复 总被引:3,自引:0,他引:3
用PAM脉冲调制荧光仪测定叶绿素荧光的变化研究了黄瓜幼苗子叶在PFD为50和100μmolm-2s-1,温度为4、7、10、15℃下的光抑制及其恢复。结果表明,黄瓜幼苗子叶Fv/Fm随着温度的下降和PFD的增加而下降,并且增加等量的PFD在4℃下比在10℃下引起更大的Fv/Fm下降。在黑暗条件下光抑制有轻微恢复,但完士恢复必需光照,且恢复起始时的光照十分重要。DTT可部分抑制叶绿素荧光Fo和Fm的猝灭,且15℃下比在4℃下抑制效果更大。CAP能强烈地加剧光抑制并几乎完全抑制恢复,且10℃下比在4℃下对光抑制的加剧作用更大。冷锻炼提高了黄瓜幼苗抵抗低温先抑制的能力,而CAP对冷锻炼苗比未锻炼苗的低温光抑制具有更大的加剧作用。 相似文献
110.
黄瓜幼苗的冷锻炼与低温引起的光抑制李晓萍,陈贻竹,李平,郭俊彦(中国科学院华南植物研究所,广州510650)关键词:低温引起的光抑制,荧光猝灭,冷锻炼,黄瓜幼苗低温使植物利用光能的能力降低从而引起或加剧光抑制(has等1983)。在光抑制中常以叶绿素... 相似文献