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141.
142.
Capacitative Ca2+ entry exists in rat glioma C6 cells; however, how the information of depletion of Ca2+ in intracellular stores transmits to the plasma membrane is unknown. In the present study, we examined whether Ca2+ influx factor (CIF) causes capacitative Ca2+ entry in C6 cells. CIF was extracted from non-treated (Non-CIF), bombesin-treated (BBS-CIF) and thapsigargin-treated (TG-CIF) C6 cells by a reverse-phase silica cartridge. The addition of BBS-CIF and TG-CIF gradually increased cytoplasmic Ca2+ concentration ([Ca2+]i) but Non-CIF did not increase [Ca2+]i. Neither BBS-CIF nor TG-CIF elevated [Ca2+]i in the absence of extracellular Ca2+. Gd3+ inhibited the increase in [Ca2+]i induced by BBS-CIF and TG-CIF. Genistein abolished an elevation of [Ca2+]i induced by BBS-CIF and TG-CIF. BBS-CIF and TG-CIF did not increase inositol 1,4,5-trisphosphate accumulation. The results suggest that capacitative Ca2+ entry is caused by CIF in rat glioma C6 cells. 相似文献
143.
Ayaka Shinkawa Katsuro Yaoi Tomoyuki Kadotani Morikazu Imamura Nobuo Koizumi Hidenori Iwahana Ryoichi Sato 《Current microbiology》1999,39(1):14-20
We investigated the binding proteins for three Cry toxins, Cry1Aa, Cry1Ac, and the phylogenetically distant Cry9Da, in the
midgut cell membrane of the silkworm. In a ligand blot experiment, Cry1Ac and Cry9Da bound to the same 120-kDa aminopeptidase
N (APN) as Cry1Aa. A competition experiment with the ligand blot indicated that the three toxins share the same binding site
on several proteins. The values of the dissociation constants of the three Cry toxins and 120-kDa APN are as low as the case
of other Cry toxins and receptors. These results suggest that distantly related Cry toxins bind to the same site on the same
proteins, especially with APN. We propose that the conserved structure in these three toxins includes the receptor-binding
site.
Received: 12 January 1998 / Accepted: 17 February 1999 相似文献
144.
Sachiko Komatsu Ayaka Yaguchi Kouwa Yamashita Masao Nagaoka Mitsuteru Numazawa 《Steroids》2009,74(12):884-889
Inhibition of aromatase is an efficient approach for the prevention and treatment of breast cancer. New 6β,19-bridged steroid analogs of androstenedione, 6β,19-epithio- and 6β,19-methano compounds 11 and 17, were synthesized starting from 19-hydroxyandrostenedione (6) and 19-formylandrost-5-ene-3β,17β-yl diacetate (12), respectively, as aromatase inhibitors. All of the compounds including known steroids 6β,19-epoxyandrostenedione (4) and 6β,19-cycloandrostenedione (5) tested were weak to poor competitive inhibitors of aromatase and, among them, 6β,19-epoxy steroid 4 provided only moderate inhibition (Ki: 2.2 μM). These results show that the 6β,19-bridged groups of the inhibitors interfere with binding in active site of aromatase. 相似文献
145.
Ca2+/Calmodulin-dependent Protein Kinase IV-mediated LIM Kinase Activation Is Critical for Calcium Signal-induced Neurite Outgrowth 总被引:1,自引:0,他引:1
146.
147.
Rie Miyauchi Katsuhiro Kawakami Masao Ito Norikazu Matsuhashi Hitoshi Ohki Hiroaki Inagaki Hisashi Takahashi Makoto Takemura 《Bioorganic & medicinal chemistry》2009,17(19):6879-6889
A series of novel 6-desfluoro [des-F(6)] and 6-fluoro-1-[(1R,2S)-2-fluorocyclopropan-1-yl]-8-methoxyquinolones bearing 3-(1-aminocycloalkyl)pyrrolidin-1-yl substituents at the C-7 position (1–6) was synthesized to obtain potent drugs for nosocomial infections caused by Gram-positive pathogens. The des-F(6) compounds 4–6 exhibited at least four times more potent activity against representative Gram-positive bacteria than ciprofloxacin or moxifloxacin. Among the derivatives, 7-[(3R)-3-(1-aminocyclopropan-1-yl)pyrrolidin-1-yl] derivative 4, which showed favorable profiles in preliminary toxicological and non-clinical pharmacokinetic studies, exhibited potent antibacterial activity against clinically isolated Gram-positive pathogens that had become resistant to one or more antibiotics. 相似文献
148.
149.
Characterization of UDP-glucose dehydrogenase isoforms in the medicinal legume Glycyrrhiza uralensis
Ayumi Kawasaki Ayaka Chikugo Keita Tamura Hikaru Seki Toshiya Muranaka 《Plant Biotechnology》2021,38(2):205
Uridine 5′-diphosphate (UDP)-glucose dehydrogenase (UGD) produces UDP-glucuronic acid from UDP-glucose as a precursor of plant cell wall polysaccharides. UDP-glucuronic acid is also a sugar donor for the glycosylation of various plant specialized metabolites. Nevertheless, the roles of UGDs in plant specialized metabolism remain poorly understood. Glycyrrhiza species (licorice), which are medicinal legumes, biosynthesize triterpenoid saponins, soyasaponins and glycyrrhizin, commonly glucuronosylated at the C-3 position of the triterpenoid scaffold. Often, several different UGD isoforms are present in plants. To gain insight into potential functional differences among UGD isoforms in triterpenoid saponin biosynthesis in relation to cell wall component biosynthesis, we identified and characterized Glycyrrhiza uralensis UGDs (GuUGDs), which were discovered to comprise five isoforms, four of which (GuUGD1–4) showed UGD activity in vitro. GuUGD1–4 had different biochemical properties, including their affinity for UDP-glucose, catalytic constant, and sensitivity to feedback inhibitors. GuUGD2 had the highest catalytic constant and highest gene expression level among the GuUGDs, suggesting that it is the major isoform contributing to the transition from UDP-glucose to UDP-glucuronic acid in planta. To evaluate the contribution of GuUGD isoforms to saponin biosynthesis, we compared the expression patterns of GuUGDs with those of saponin biosynthetic genes in methyl jasmonate (MeJA)-treated cultured stolons. GuUGD1–4 showed delayed responses to MeJA compared to those of saponin biosynthetic genes, suggesting that MeJA-responsive expression of GuUGDs compensates for the decreased UDP-glucuronic acid pool due to consumption during saponin biosynthesis. 相似文献
150.
Establishing and maintaining a morphogen gradient are important in the growth and patterning of developing organs. When a discontinuity in a morphogen signal gradient is created by somatic mutant clones with aberrant intensities of morphogen signals within the Drosophila wing disc, the clones can be removed by apoptosis to restore the morphogen signal gradient. This apoptosis is termed "morphogenetic apoptosis" and has been observed to occur in a cell autonomous or non-cell autonomous manner. This review discusses possible molecular mechanisms of both autonomous and non-cell autonomous apoptosis in addition to similar cellular events in reference to recent findings. 相似文献