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981.
982.
In this investigation, a gas chromatography/mass spectrometry (GC/MS)-based metabolomic protocol for adherent cell cultures was developed using statistical design of experiments. Cell disruption, metabolite extraction, and the GC/MS settings were optimized aiming at a gentle, unbiased, sensitive, and high-throughput metabolomic protocol. Due to the heterogeneity of the metabolome and the inherent selectivity of all analytical techniques, development of unbiased protocols is highly complex. Changing one parameter of the protocol may change the response of many groups of metabolites. In this investigation, statistical design of experiments and multivariate analysis also allowed such interaction effects to be taken into account. The protocol was validated with respect to linear range, precision, and limit of detection in a clonal rat insulinoma cell line (INS-1 832/13). The protocol allowed high-throughput profiling of metabolites covering the major metabolic pathways. The majority of metabolites displayed a linear range from a single well in a 96-well plate up to a 10 cm culture dish. The method allowed a total of 47 analyses to be performed in 24 h. 相似文献
983.
Jaime Guillén 《生物化学与生物物理学报:生物膜》2010,1798(3):327-337
We have identified a membrane-active region in the HCV NS4B protein by studying membrane rupture induced by a NS4B-derived peptide library on model membranes. This segment corresponds to one of two previously predicted amphipathic helix and define it as a new membrane association domain. We report the binding and interaction with model membranes of a peptide patterned after this segment, peptide NS4BH2, and show that NS4BH2 strongly partitions into phospholipid membranes, interacts with them, and is located in a shallow position in the membrane. Furthermore, changes in the primary sequence cause the disruption of the hydrophobicity along the structure and prevent the resulting peptide from interacting with the membrane. Our results suggest that the region where the NS4BH2 is located might have an essential role in the membrane replication and/or assembly of the viral particle through the modulation of the replication complex. Our findings therefore identify an important region in the HCV NS4B protein which might be implicated in the HCV life cycle and possibly in the formation of the membranous web. 相似文献
984.
985.
986.
Aline Lara Denis D. Damasceno Rita Pires Robert Gros Enéas R. Gomes Mariana Gavioli Ricardo F. Lima Diogo Guimar?es Patricia Lima Carlos Roberto Bueno Jr. Anilton Vasconcelos Danilo Roman-Campos Cristiane A. S. Menezes Raquel A. Sirvente Vera M. Salemi Charles Mady Marc G. Caron Anderson J. Ferreira Patricia C. Brum Rodrigo R. Resende Jader S. Cruz Marcus Vinicius Gomez Vania F. Prado Alvair P. de Almeida Marco A. M. Prado Silvia Guatimosim 《Molecular and cellular biology》2010,30(7):1746-1756
987.
Cláudia Funchal Carlos Augusto Souza Carvalho Tanise Gemelli Andressa S. Centeno Robson Brum Guerra Mirian Salvador Caroline Dani Adriana Coitinho Rosane Gomez 《Cellular and molecular neurobiology》2010,30(7):1135-1142
Organotellurium compounds have been synthesized since 1840, but pharmacological and toxicological studies about them are still
incipient. Therefore, the objective of this study was to verify the effect of acute administration of the organochalcogen
3-butyl-1-phenyl-2-(phenyltelluro)oct-en-1-one on some parameters of oxidative stress in the brain of 30-day-old rats. Animals
were treated intraperitoneally with a single dose of the organotellurium (125, 250, or 500 μg/kg body weight) and sacrificed
60 min after the injection. The cerebral cortex, the hippocampus, and the cerebellum were dissected and homogenized in KCl.
Afterward, thiobarbituric acid reactive substances (TBARS), carbonyl, sulfhydryl, catalase (CAT), superoxide dismutase (SOD),
nitric oxide (NO) formation, and hydroxyl radical production were measured in the brain. The organotellurium enhanced TBARS
in the cerebral cortex and the hippocampus, and increased protein damage (carbonyl) in the cerebral cortex and the cerebellum.
In contrast, the compound provoked a reduced loss of thiol groups measured by the sulfhydryl assay in all the tissues studied.
Furthermore, the activity of the antioxidant enzyme CAT was reduced by the organochalcogen in the cerebral cortex and the
cerebellum, and the activity of SOD was inhibited in all the brain tissues. Moreover, NO production was increased in the cerebral
cortex and the cerebellum by this organochalcogen, and hydroxyl radical formation was also enhanced in the cerebral cortex.
Our findings indicate that this organotellurium compound induces oxidative stress in the brain of rats, corroborating that
this tissue is a potential target for organochalcogen action. 相似文献
988.
989.
A new cephalostatin/ritterazine analogue was prepared from the commercially available hecogenin acetate and the natural cytotoxic steroid 22-epi-hippuristanol. The method involved the reductive dimerization of enaminoketones (condensation of α-aminoketones) and condensation between an enaminoketone and an α-hydroxyketone. The new analogue showed higher cytotoxic activity than the cytotoxic 22-epi-hippuristanol against MDA-MB-231, A-549 and HT-29 cultured tumor cell lines. 相似文献
990.
Robin F. A. Moritz Nizar Haddad Ahmed Bataieneh Benny Shalmon Abraham Hefetz 《Biological invasions》2010,12(5):1093-1099
The dwarf honeybee, Apis florae, is an open nesting honeybee typical to Southern Asia. In the past decades it has been accidentally introduced by man to East Africa and the Arabian Peninsula where the species established sustainable and expanding populations. Recently it has also been introduced to Aqaba and Eilat, where it has also established expanding populations. We here study the genetic structure of this invasive population with nine microsatellite DNA markers to reconstruct the invasion history. The population shows indications of an extreme bottleneck suggesting that it established itself very recently and may have originated from a single introduced colony only. The impact of the species for both apiculture and conservation of biodiversity is discussed. 相似文献