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791.
792.
The effect of 4-thiouridine (4SU) on metabolic activities oforganelles other than plastids was investigated by examininggrowth parameters, cellular enzyme activities and metabolicbehaviors of greening radish seedlings germinated and grownwith 4SU. Seedling growth was not severely affected by 4SU culture.Mitochondrial, peroxisomal and microsomal marker enzymes andcytoplasmic enzyme activities were not generally changed inthe 4SU-cultured radish cotyledons. The respiration rate ofmitochondria isolated from 4SU-cultured cotyledons was alsonormal. Some soluble enzymes of the isolated plastids had normalor even higher activities. However, chloroplastic pigments andribulose bisphosphate carboxylase activity decreased with increasingconcentration of 4SU in the culture medium. We concluded thatthe inhibitory effect of 4SU was limited to chloroplast development. (Received December 4, 1979; ) 相似文献
793.
794.
Mostofa Jamal Kiyoshi Ameno Naoko Tanaka Asuka Ito Ayaka Takakura Mitsuru Kumihashi Hiroshi Kinoshita 《Neurochemical research》2016,41(5):1029-1034
This paper reports, for the first time, on the analysis of ethanol (EtOH) and acetaldehyde (AcH) concentrations in the blood and brains of Aldh2-knockout (Aldh2-KO) and C57B6/6J (WT) mice. Animals were administrated EtOH (1.0, 2.0 or 4.0 g/kg) or 4-methylpyrazole (4-MP, 82 mg/kg) plus AcH (50, 100 or 200 mg/kg) intraperitoneally. During the blood tests, samples from the orbital sinus of the eye were collected. During the brain tests, dialysates were collected every 5 min (equal to a 15 µl sample) from the striatum using in vivo brain microdialysis. Samples were collected at 5, 10, 15, 20, 25, 30 and 60 min intervals post-EtOH and -AcH injection, and then analyzed by head-space GC. In the EtOH groups, high AcH levels were found in the blood and brains of Aldh2-KO mice, while only small traces of AcH were seen in the blood and brains of WT mice. No significant differences in EtOH levels were observed between the WT and the Aldh2-KO mice for either the EtOH dose. EtOH concentrations in the brain were comparable to the EtOH concentrations in the blood, but the AcH concentrations in the brain were four to five times lower compared to the AcH concentrations in the blood. In the AcH groups, high AcH levels were found in both WT and Aldh2-KO mice. Levels reached a sharp peak at 5 min and then quickly declined for 60 min. Brain AcH concentrations were almost equal to the concentrations found in the blood, where the AcH concentrations were approximately two times higher in the Aldh2-KO mice than in the WT mice, both in the blood and the brain. Our results suggest that systemic EtOH and AcH administration can cause a greater increase in AcH accumulation in the blood and brains of Aldh2-KO mice, where EtOH concentrations in the Aldh2-KO mice were comparable to the EtOH concentrations in the WT mice. Furthermore, detection of EtOH and AcH in the blood and brain was found to be dose-dependent in both genotypes. 相似文献
795.
796.
T Morio H Urushihara T Saito Y Ugawa H Mizuno M Yoshida R Yoshino B N Mitra M Pi T Sato K Takemoto H Yasukawa J Williams M Maeda I Takeuchi H Ochiai Y Tanaka 《DNA research》1998,5(6):335-340
In an effort to identify and characterize genes expressed during multicellular development ill Dictyostelium, we have undertaken a cDNA sequencing project. Using size-fractionated subsets of cDNA from the first finger stage, two sets of gridded libraries were constructed for cDNA sequencing. One, library S, consisting of 9984 clones, carries relatively short inserts, and the other, library L, which consists of 8448 clones, has longer inserts. We sequenced all the selected clones in library S from their 3'-ends, and this generated 3093 non-redundant, expressed sequence tags (ESTs). Among them, 246 ESTs hit known Dictyostelium genes and 910 showed significant similarity to genes of Dictyostelium and other organisms. For library L, 1132 clones were randomly sequenced and 471 non-redundant ESTs were obtained. In combination, the ESTs from the two libraries represent approximately 40% of genes expressed in late development, assuming that the non-redundant ESTs correspond to independent genes. They will provide a useful resource for investigating the genetic networks that regulate multicellular development of this organism. 相似文献
797.
A Inoue Y Komatsu J Ochiai S Itagaki H Nishide M Shikano H Hemmi N Numao 《Cell biology international reports》1990,14(10):887-896
Ultimobranchial calcitonins (CTs), known to stimulate cAMP production, inhibited the growth of a porcine kidney cell line LLC-PK1. This inhibition was accompanied by degenerative changes including vacuole formation and cell detachment. The electron microscopic study revealed marked swelling of rough endoplasmic reticulum (RER). Other cAMP-increasing agents such as human CT, arginine, vasopressin, and forskolin showed less growth inhibitory activities and no induction of the degenerative changes. These results indicate that the growth inhibition of LLC-PK1 by ultimobranchial CTs is mainly due to cellular death caused by the swelling of RER via a signalling pathway other than the cAMP-dependent event(s). 相似文献