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Yamaguchi T Hashiguchi K Katsuki S Iwamoto W Tsuruhara S Terada S 《Cellular & molecular biology letters》2008,13(1):49-57
We previously demonstrated that caspase-3, an executioner of apoptosis, is activated in the pressure-induced apoptosis of
murine erythroleukemia (MEL) cells (at 100 MPa). Here, we examined the pathway of caspase-3 activation using peptide substrates
and caspase inhibitors. Using the substrates of caspases-8 and -9, it was found that both are activated in cells under high
pressure. The production of nuclei with sub-G1 DNA content in 100 MPa-treated MEL cells was suppressed by inhibitors of caspases-8
and -9, and pan-caspase. In 100 MPa-treated cells, pan-caspase inhibitor partially prevented the cytochrome c release from the mitochondria and the breakdown of mitochondrial membrane potential. These results suggest that the intrinsic
and extrinsic pathways are activated in apoptotic signaling during the high pressure-induced death of MEL cells. 相似文献
23.
The largest genus of the Eriocaulaceae, Paepalanthus, presents many taxonomic problems. Some of these were identified during studies of Eriocaulaceae from the flora of S?o Paulo
State and Caparaó National Park. Here, we propose changes in nomenclature as a solution to such issues, based on type collections,
recent collections and field observations. These changes are in agreement with the taxonomic species concept, and the rules
established by the International Code of Botanical Nomenclature. We define six lectotypes: P. gneissicola, P. caparoensis, P. caldensis, P. lundii, P. oerstedianus and P. striatus, and six synonyms: P. gneissicola = P. acantholimon, P. loefgrenianus = P. aequalis, P. multicostatus = P. calvus, P. scopulifer = P. caparoensis, P. neocaldensis = P. flaccidus and P. macrotrichus = P. lundii. We also present comments on morphology, protologue and type collections. 相似文献
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Sharifi K Morihiro Y Maekawa M Yasumoto Y Hoshi H Adachi Y Sawada T Tokuda N Kondo H Yoshikawa T Suzuki M Owada Y 《Histochemistry and cell biology》2011,136(5):501-513
Reactive gliosis, in which astrocytes as well as other types of glial cells undergo massive proliferation, is a common hallmark of all brain pathologies. Brain-type fatty acid-binding protein (FABP7) is abundantly expressed in neural stem cells and astrocytes of developing brain, suggesting its role in differentiation and/or proliferation of glial cells through regulation of lipid metabolism and/or signaling. However, the role of FABP7 in proliferation of glial cells during reactive gliosis is unknown. In this study, we examined the expression of FABP7 in mouse cortical stab injury model and also the phenotype of FABP7-KO mice in glial cell proliferation. Western blotting showed that FABP7 expression was increased significantly in the injured cortex compared with the contralateral side. By immunohistochemistry, FABP7 was localized to GFAP(+) astrocytes (21% of FABP7(+) cells) and NG2(+) oligodendrocyte progenitor cells (62%) in the normal cortex. In the injured cortex there was no change in the population of FABP7(+)/NG2(+) cells, while there was a significant increase in FABP7(+)/GFAP(+) cells. In the stab-injured cortex of FABP7-KO mice there was decrease in the total number of reactive astrocytes and in the number of BrdU(+) astrocytes compared with wild-type mice. Primary cultured astrocytes from FABP7-KO mice also showed a significant decrease in proliferation and omega-3 fatty acid incorporation compared with wild-type astrocytes. Overall, these data suggest that FABP7 is involved in the proliferation of astrocytes by controlling cellular fatty acid homeostasis. 相似文献
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Tomoko Satake Atsushi Suzuki Tomoko Satake Kazunari Yamashita Kenji Hayashi Satoko Miyatake Miwa Tamura-Nakano Hiroshi Doi Yasuhide Furuta Go Shioi Eriko Miura Yukari H Takeo Kunihiro Yoshida Hiroyuki Yahikozawa Naomichi Matsumoto Michisuke Yuzaki Atsushi Suzuki 《The EMBO journal》2017,36(9):1227-1242
The axon initial segment (AIS) is a specialized domain essential for neuronal function, the formation of which begins with localization of an ankyrin-G (AnkG) scaffold. However, the mechanism directing and maintaining AnkG localization is largely unknown. In this study, we demonstrate that in vivo knockdown of microtubule cross-linking factor 1 (MTCL1) in cerebellar Purkinje cells causes loss of axonal polarity coupled with AnkG mislocalization. MTCL1 lacking MT-stabilizing activity failed to restore these defects, and stable MT bundles spanning the AIS were disorganized in knockdown cells. Interestingly, during early postnatal development, colocalization of MTCL1 with these stable MT bundles was observed prominently in the axon hillock and proximal axon. These results indicate that MTCL1-mediated formation of stable MT bundles is crucial for maintenance of AnkG localization. We also demonstrate that Mtcl1 gene disruption results in abnormal motor coordination with Purkinje cell degeneration, and provide evidence suggesting possible involvement of MTCL1 dysfunction in the pathogenesis of spinocerebellar ataxia. 相似文献
29.
Ryousuke Takahashi Katsumi Kawamura Jianguo Hu †Michiyuki Hayashi Takeo Deguchi 《Journal of neurochemistry》1996,67(2):525-529
Abstract: To study the level of ciliary neurotrophic factor (CNTF) in human nervous tissues, we developed a sensitive enzyme-linked immunoassay using a specific antibody against human CNTF. This method allowed us to detect as little as 0.3 ng/ml of human CNTF with good linearity and accuracy. Using this method, CNTF levels were determined in human sciatic nerves obtained at autopsy from 21 amyotrophic lateral sclerosis (ALS) patients and 48 subjects who had died of other neurological diseases. CNTF genotypes were also determined. The results indicated that CNTF levels were high in the normal homozygotes and approximately halved in the heterozygote subjects. There was, however, no significant difference in CNTF levels in the sciatic nerves between ALS and other neurological disease patients, indicating that the CNTF level was mainly determined by its genotypes and that the level in the sciatic nerves was not reduced in ALS patients. 相似文献
30.
Tricholoma matsutake was isolated into pure cultures from field samples of ectomycorrhizas onPinus densiflora. The mycorrhizal tips were collected at different times of the year from a colony ofT. matsutake in aP. densiflora stand. The mycorrhizal tips were continuously washed with sterilized distilled water and diluted Tween 80 solution, surface-sterilized
with calcium hypochlorite solution, and inoculated on several kinds of nutrient agar media. Most of the mycorrhizal tips collected
in winter and spring produced colonies that were morphologically similar to cultures ofT. matsutake isolated from basidiocarps. The identity of isolates obtained from mycorrhizas was further confirmed to beT. matsutake based on fungal morphology and RFLP patterns of PCR amplified rDNA. The feasibility ofT. bakamatsutake isolation into pure culture from ectomycorrhizas onQuercus serrata was also confirmed. These results indicated that mycelium of matsutake mushrooms can be isolated into pure culture from ectomycorrhizas
at different times of the year. Mycorrhizas of bothT. matsutake andT. bakamatsutake were not observed to have any specific association with soil fungi such asMortierella spp. 相似文献