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401.
Rodolpho M. Albano Paulo A.S. Mourão 《Biochimica et Biophysica Acta (BBA)/General Subjects》1983,760(1):192-196
The tunic of several Ascidian species, and the body wall of a sea cucumber, contain high amounts of sulfated glycans, at a concentration which is similar to that of sulfated glycosaminoglycans in vertebrate cartilales. The glycans from the different species are distinguished by the pattern of electrophoretic migration and by the molar proportion of amino sugars, hexoses and sulfate. The possibility that these compounds be involved in the maintenance of the integrity of these tissues, resembling the strutural function of the glycosaminoglycans in vertebrate cartilages, is discussed. 相似文献
402.
Agnieszka Skarzyska Magdalena Pawekowicz Wojciech Plder 《Physiology and Molecular Biology of Plants》2021,27(5):985
The development of new plant varieties by genetic modification aims at improving their features or introducing new qualities. However, concerns about the unintended effects of transgenes and negative environmental impact of genetically modified plants are an obstacle for the use of these plants in crops. To analyze the impact of transgenesis on plant genomes, we analyze three cucumber transgenic lines with an introduced thaumatin II gene. After genomes sequencing, we analyzed the transgene insertion site and performed variant prediction. As a result, we obtained similar number of variants for all analyzed lines (average of 4307 polymorphisms), with high abundance in one region of chromosome 4. According to SnpEff analysis, the presence of genomic variants generally does not influence the genome functionality, as less than 2% of polymorphisms have high impact. Moreover, analysis indicates that these changes were more likely induced by in vitro culture than by the transgenesis itself. The insertion site analysis shows that the region of transgene integration could cause changes in gene expression, by gene disruption or loss of promoter region continuity.Supplementary InformationThe online version contains supplementary material available at 10.1007/s12298-021-00990-8. 相似文献
403.
Xin Zhao Jingyuan Lu Weiwei Jin a National Maize Improvement Center of China Key Laboratory of Crop Genetic Improvement Genome of Ministry of Agriculture Beijing Key Laboratory of Crop Genetic Improvement China Agricultural University Beijing China b College of Bioscience Biotechnology Hunan Agricultural University Changsha China c Opening Lab of Genetic Improvement of Agricultural Crops of Ministry of Agriculture Sino-D... 《Acta Genetica Sinica》2011,(1)
Repetitive DNA sequences with variability in copy number or/and sequence polymorphism can be employed as useful molecular markers to study phylogenetics and identify species/chromosomes when combined with fluorescence in situ hybridization(FISH).Cucumis sativus has three variants,Cucumis sativus L.var.sativus,Cucumis sativus L.var.hardwickii and Cucumis sativus L.var.xishuangbannesis.The phylogenetics among these three variants has not been well explored using cytological landmarks.Here,we concentrate on... 相似文献
404.
Khaled M. Suliman Elmeer Michael J. Hennerty 《Plant Cell, Tissue and Organ Culture》2008,95(3):381-384
Somatic embryogenesis of cucumber was affected by auxin and light during the induction phase. In the light, 2,4-dichlorophenoxyacetic
acid (2,4-D) alone induced little embryogenesis, while combined with naphthaleneacetic acid (NAA) it induced 1.25 somatic
embryos (SEs) per callus. In the dark 2,4-D alone induced 5 times more SEs per callus. 相似文献
405.
Milky spots in the greater omentum are predominant sites of local tumour cell proliferation and accumulation in the peritoneal cavity 总被引:5,自引:0,他引:5
Lambert F. G. Krist Miranda Kerremans Donna M. Broekhuis-Fluitsma Inge L. Eestermans Sybren Meyer Robert H. J. Beelen 《Cancer immunology, immunotherapy : CII》1998,47(4):205-212
The role that milky spots in the greater omentum play in tumour cell spread in the peritoneal cavity is presently not fully
understood. To study whether intraperitoneally injected tumour cells appear preferentially in milky spots of the greater omentum
and to study the changes in the greater omentum, and especially in the cell population of milky spots after tumour cell infiltration,
the following study was performed. A detailed temporal sequences of changes in morphology and cellular composition in milky
spots of the greater omentum of Wag/Rij rats 5, 15, 30, 60 min, 2, 4, 8, 16, 24 h, 2, 4, 8 days and 2 and 4 weeks after intraperitoneal
administration of 2.0 × 106 CC 531 tumour cells was investigated by light microscopy and electron microscopy (pre-embedding labelling). Our data showed
that the milky spots in the greater omentum were the sites to which tumour cells migrated preferentially from the peritoneal
cavity. The tumour cells infiltrated the milky spots and formed clusters within. The cellular population in milky spots reacted
by a very rapid influx of young macrophages during the first hour and an increase of the total number of cells (P < 0.01). After 4 h tumour cells were also located on the greater omentum outside the area of the milky spots. Around these
tumour cell deposits, new milky spots are formed, which increased the total number of milky spots. The cells present in milky
spots are not capable of reversing the growth of tumours and finally a solid omental cake of tumour cells is formed.
Received: 30 June 1998 / Accepted: 3 September 1998 相似文献
406.
The uptake and the transport of14C-labeled epibrassinolide in intact seedlings of cucumber and wheat
Naoko Nishikawa Susumu Toyama Atsuhiko Shida Fumio Futatsuya 《Journal of plant research》1994,107(2):125-130
The uptake and the transport of exogenously applied epibrassinolide (EBR) in seedlings of cucumber and wheat were examined
by autoradiography using14C-EBR.14C-EBR was applied to roots, young and mature leaves, and the shoot apex. When applied to roots,14C-EBR was readily taken up and was swiftly transported throughout both plant species. When14C-EBR was applied to the adaxial surface of a young cucumber leaf, it was readily taken up, but was very slowly transported.
In cucumber leaves,14C-EBR was transported throughout the treated leaf after 3 days of treatment, and then it was transported to upper leaves from
the treated leaf after 7 days. Some 6.3% of applied14C-EBR was transported to the newly expanded leaves. In wheat leaves,14C-EBR was transported only in the apical direction from the treated spot after 3 days of treatment, but it was not transported
from the treated leaf to the other leaves or organs even after 7 days. Some 1.3% of applied14C-EBR was transported to the tip area of the treated leaf. These results indicate that exogenous EBR applied to intact plants
is acropetally transported. 相似文献
407.
Summary The presence in the rat omentum of intercellular pores (the classical stomata of von Recklinghausen) between the mesothelial cells overlying aggregates of lymphoreticular cells (the classical milky spots of Ranvier) and the apparent migration of lymphocytes through these stomata were recorded for the first time by scanning electron microscopy. Previous studies on passage of cells across the peritoneum and omentum used experimentally administered cells, while in the present study no cells were administered to the rats and their own lymphocytes were observed in situ. The possible role of lymphocytes in the peritoneal cavity is also briefly discussed. 相似文献
408.