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991.
Keigo Mizusawa Kenji Abe Shinsuke Sando Yasuhiro Aoyama 《Bioorganic & medicinal chemistry》2009,17(6):2381-2387
We have synthesized a series of 5′-phosphorylated and 5′-cytidylyl-(3′–5′)-cytidylyl-(3′–5′)-puromycin derivatives that have backbone-elongated substrates. All the synthesized puromycin derivatives showed good solubility in water and were applied to translation inhibitory assay in a reconstituted Escherichia coli translation system. 相似文献
992.
993.
Yasuhiro Yamauchi Monika A. Ward W. Steven Ward 《Journal of cellular biochemistry》2009,107(2):214-223
To prevent duplicate DNA synthesis, metazoan replication origins are licensed during G1. Only licensed origins can initiate replication, and the cytoplasm interacts with the nucleus to inhibit new licensing during S phase. DNA replication in the mammalian one‐cell embryo is unique because it occurs in two separate pronuclei within the same cytoplasm. Here, we first tested how long after activation the oocyte can continue to support licensing. Because sperm chromatin is licensed de novo after fertilization, the timing of sperm injection can be used to assay licensing initiation. To experimentally skip some of the steps of sperm decondensation, we injected mouse sperm halos into parthenogenetically activated oocytes. We found that de novo licensing was possible for up to 3 h after oocyte activation, and as early as 4 h before DNA replication began. We also found that the oocyte cytoplasm could support asynchronous initiation of DNA synthesis in the two pronuclei with a difference of at least 2 h. We next tested how tightly the oocyte cytoplasm regulates DNA synthesis by transferring paternal pronuclei from zygotes generated by intracytoplasmic sperm injection (ICSI) into parthenogenetically activated oocytes. The pronuclei from G1 phase zygotes transferred into S phase ooplasm were not induced to prematurely replicate and paternal pronuclei from S phase zygotes transferred into G phase ooplasm continued replication. These data suggest that the one‐cell embryo can be an important model for understanding the regulation of DNA synthesis. J. Cell. Biochem. 107: 214–223, 2009. © 2009 Wiley‐Liss, Inc. 相似文献
994.
Tomoharu Iino Yasuhiro Sasaki Makoto Bamba Morihiro Mitsuya Akio Ohno Kenji Kamata Hideka Hosaka Hiroko Maruki Mayumi Futamura Riki Yoshimoto Sumika Ohyama Kaori Sasaki Masato Chiba Norikazu Ohtake Yasufumi Nagata Jun-ichi Eiki Teruyuki Nishimura 《Bioorganic & medicinal chemistry letters》2009,19(19):5531-5538
We describe design, syntheses and structure–activity relationships of a novel class of 4,6-disubstituted quinazoline glucokinase activators. Prototype quinazoline leads (4 and 5) were designed based on the X-ray analyses of the previous 2-aminobenzamide lead classes. Modifications of the quinazoline leads led to the identification of a potent GK activator (21d). 相似文献
995.
Tomonori Deguchi Mariko Itoh Hiroko Urawa Tomohiro Matsumoto Sohei Nakayama Takashi Kawasaki Takeshi Kitano Shoji Oda Hiroshi Mitani Taku Takahashi Takeshi Todo Junichi Sato Kiyotaka Okada Kohei Hatta Shunsuke Yuba Yasuhiro Kamei 《Development, growth & differentiation》2009,51(9):769-775
Heat shock promoters are powerful tools for the precise control of exogenous gene induction in living organisms. In addition to the temporal control of gene expression, the analysis of gene function can also require spatial restriction. Recently, we reported a new method for in vivo, single‐cell gene induction using an infrared laser‐evoked gene operator (IR‐LEGO) system in living nematodes (Caenorhabditis elegans). It was demonstrated that infrared (IR) irradiation could induce gene expression in single cells without incurring cellular damage. Here, we report the application of IR‐LEGO to the small fish, medaka (Japanese killifish; Oryzias latipes) and zebrafish (Danio rerio), and a higher plant (Arabidopsis thaliana). Using easily observable reporter genes, we successfully induced gene expression in various tissues in these living organisms. IR‐LEGO has the potential to be a useful tool in extensive research fields for cell/tissue marking or targeted gene expression in local tissues of small fish and plants. 相似文献
996.
Yasuhiro Onoue Toshiharu Suzuki Max Davidson Owe Orwar Kazuhiko Kinosita Jr. 《生物化学与生物物理学报:生物膜》2009,1788(6):1332-865
We present an experimental system that allows visualization of conformational changes in membrane proteins at the single-molecule level. The target membrane protein is reconstituted in a giant liposome for independent control of the aqueous environments on the two sides of the membrane. For direct observation of conformational changes, an extra-liposomal site(s) of the target protein is bound to a glass surface, and a probe that is easily visible under a microscope, such as a micron-sized plastic bead, is attached to another site on the intra-liposomal side. A conformational change, or an angular motion in the tiny protein molecule, would manifest as a visible motion of the probe. The attachment of the protein on the glass surface also immobilizes the liposome, greatly facilitating its manipulation such as the probe injection. As a model system, we reconstituted ATP synthase (FOF1) in liposomes tens of μm in size, attached the protein specifically to a glass surface, and demonstrated its ATP-driven rotation in the membrane through the motion of a submicron bead. 相似文献
997.
Hiroyuki Kayamuro Yasuo Yoshioka Yasuhiro Abe Kazufumi Katayama Kohei Yamashita Tomoaki Yoshikawa Takachika Hiroi Yuichi Kawai Haruhiko Kamada Shin-ichi Tsunoda Yasuo Tsutsumi 《Biochemical and biophysical research communications》2009,384(3):296-300
The identification of cytokine adjuvants capable of inducing an efficient mucosal immune response against viral pathogens has been long anticipated. Here, we attempted to identify the potential of tumor necrosis factor superfamily (TNFS) cytokines to function as mucosal vaccine adjuvants. Sixteen different TNFS cytokines were used to screen mucosal vaccine adjuvants, after which their immune responses were compared. Among the TNFS cytokines, intranasal immunization with OVA plus APRIL, TL1A, and TNF-α exhibited stronger immune response than those immunized with OVA alone. TL1A induced the strongest immune response and augmented OVA-specific IgG and IgA responses in serum and mucosal compartments, respectively. The OVA-specific immune response of TL1A was characterized by high levels of serum IgG1 and increased production of IL-4 and IL-5 from splenocytes of immunized mice, suggesting that TL1A might induce Th2-type responses. These findings indicate that TL1A has the most potential as a mucosal adjuvant among the TNFS cytokines. 相似文献
998.
Jun Noritake Yuko Fukata Tsuyoshi Iwanaga Naoki Hosomi Ryouhei Tsutsumi Naoto Matsuda Hideki Tani Hiroko Iwanari Yasuhiro Mochizuki Tatsuhiko Kodama Yoshiharu Matsuura David S. Bredt Takao Hamakubo Masaki Fukata 《The Journal of cell biology》2009,185(1):147-161
During development, Schwann cells (SCs) interpret different extracellular cues to regulate their migration, proliferation, and the remarkable morphological changes associated with the sorting, ensheathment, and myelination of axons. Although interactions between extracellular matrix proteins and integrins are critical to some of these processes, the downstream signaling pathways they control are still poorly understood. Integrin-linked kinase (ILK) is a focal adhesion protein that associates with multiple binding partners to link integrins to the actin cytoskeleton and is thought to participate in integrin and growth factor–mediated signaling. Using SC-specific gene ablation, we report essential functions for ILK in radial sorting of axon bundles and in remyelination in the peripheral nervous system. Our in vivo and in vitro experiments show that ILK negatively regulates Rho/Rho kinase signaling to promote SC process extension and to initiate radial sorting. ILK also facilitates axon remyelination, likely by promoting the activation of downstream molecules such as AKT/protein kinase B. 相似文献
999.
1000.
Makoto Mizunami Sae Unoki Yasuhiro Mori Daisuke Hirashima Ai Hatano Yukihisa Matsumoto 《BMC biology》2009,7(1):46-16