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261.
Satoshi Toda Takuya Hirose Kanako Kakiuchi Hirosato Kodama Keisuke Kijima Masatoshi Mochizuki 《Applied Entomology and Zoology》2014,49(2):231-239
Scirtothrips dorsalis Hood is a cosmopolitan and polyphagous thrips species. Recently, a novel strain of S. dorsalis attacking capsicum crops was found in Japan. A molecular phylogenetic analysis using mitochondrial cytochrome c oxidase subunit I sequences revealed that the capsicum-associated populations were genetically different from Japanese native strains and were closely related to Southeast Asian populations. We named the capsicum-associated populations “strain C” and the Japanese native ones “strain YT”. A total of 10 haplotypes were found in strain C and 26 in strain YT. To differentiate the two strains, we developed a multiplex-PCR method using the ribosomal ITS2 region. 相似文献
262.
Hiromi Yano Eri Oyanagi Yasuko Kato Yoshiyuki Samejima Junzo Sasaki Kozo Utsumi 《Molecular and cellular biochemistry》2010,342(1-2):95-100
Mitochondrial β-oxidation is an important system involved in the energy production of various cells. In this system, the function of l-carnitine is essential for the uptake of fatty acids to mitochondria. However, it is unclear whether or not endogenous respiration, ADP-induced O2 consumption without substrates, is caused by l-carnitine treatment. In this study, we investigated whether l-carnitine is essential to the β-oxidation of quarried fatty acids from the mitochondrial membrane by phospholipase A2 (PLA2) using isolated mitochondria from the liver of rats. Intact mitochondria were incubated in a medium containing Pi, CoA and l-carnitine. The effect of l-carnitine treatment on ADP-induced mitochondrial respiration was observed without exogenous respiratory substrate. Increase in mitochondrial respiration was induced by treatment with l-carnitine in a concentration-dependent manner. Treatment with rotenone, a complex I blocker, completely inhibited ADP-induced oxygen consumption even in the presence of l-carnitine. Moreover, the l-carnitine dependent ADP-induced mitochondrial oxygen consumption did not increase when PLA2 inhibitors were treated before ADP treatment. The l-carnitine-dependent ADP-induced oxygen consumption did contribute to ATP productions but not heat generation via an uncoupling system. These results suggest that l-carnitine might be essential to the β-oxidation of quarried fatty acids from the mitochondrial membrane by PLA2. 相似文献
263.
264.
Naoki Yamamoto Koji Hirano Hajime Kojima Mariko Sumitomo Hiromi Yamashita Masahiko Ayaki Koki Taniguchi Atsuhiro Tanikawa Masayuki Horiguchi 《In vitro cellular & developmental biology. Animal》2010,46(9):774-780
Stem/progenitor cells of the human corneal epithelium are present in the human corneal limbus, and several corneal epithelial
stem/progenitor cell markers have been reported. Recently, the neurotrophin family receptors were reported to be useful markers
of corneal epithelial stem/progenitor cells. Therefore, we examined an enzymatic separation method for obtaining corneal epithelial
stem/progenitor cells and measuring the change in the expression of low-affinity neurotrophin receptor p75 (p75NTR), a receptor belonging to the neurotrophin family. As a result, it was found that our separation method preserved cell viability.
Furthermore, p75NTR was mainly observed in epithelial basal cells as were the corneal epithelial stem/progenitor markers p63 and integrin β1.
p75NTR was also observed in the cultured cells, but its frequency decreased with passage. In conclusion, we propose that our culture
method will enable the culture of corneal stem cells and that it is a useful tool for elucidating the molecular basis of the
niche that is necessary for the maintenance of epithelial stem cells in the corneal limbus. Furthermore, we conclude that
p75NTR is a useful cell marker for evaluating the characteristics of stem/progenitor cells in culture. 相似文献
265.
Kazuyuki Tanabe Toshihiro Mita Thibaut Jombart Anders Eriksson Shun Horibe Nirianne Palacpac Lisa Ranford-Cartwright Hiromi Sawai Naoko Sakihama Hiroshi Ohmae Masatoshi Nakamura Marcelo U. Ferreira Ananias A. Escalante Franck Prugnolle Anders Björkman Anna Färnert Akira Kaneko Toshihiro Horii Andrea Manica Hirohisa Kishino Francois Balloux 《Current biology : CB》2010,20(14):1283-1289
266.
Yoshimi Tokuzawa Ken Yagi Yzumi Yamashita Yutaka Nakachi Itoshi Nikaido Hidemasa Bono Yuichi Ninomiya Yukiko Kanesaki-Yatsuka Masumi Akita Hiromi Motegi Shigeharu Wakana Tetsuo Noda Fred Sablitzky Shigeki Arai Riki Kurokawa Toru Fukuda Takenobu Katagiri Christian Sch?nbach Tatsuo Suda Yosuke Mizuno Yasushi Okazaki 《PLoS genetics》2010,6(7)
267.
Ebi M Kataoka H Shimura T Kubota E Hirata Y Mizushima T Mizoshita T Tanaka M Mabuchi M Tsukamoto H Tanida S Kamiya T Higashiyama S Joh T 《Biochemical and biophysical research communications》2010,402(3):449-454
Background and aims: Transforming growth factor-beta (TGFβ) is known to potently inhibit cell growth. Loss of responsiveness to TGFβ inhibition on cell growth is a hallmark of many types of cancer, yet its mechanism is not fully understood. Membrane-anchored heparin-binding EGF-like growth factor (proHB-EGF) ectodomain is cleaved by a disintegrin and metalloproteinase (ADAM) members and is implicated in epidermal growth factor receptor (EGFR) transactivation. Recently, nuclear translocation of the C-terminal fragment (CTF) of pro-HB-EGF was found to induce cell growth. We investigated the association between TGFβ and HB-EGF signal transduction via ADAM activation.Materials and methods: The CCK-8 assay in two gastric cancer cell lines was used to determine the effect for cell growth by TGFβ. The effect of two ADAM inhibitors was also evaluated. Induction of EGFR phosphorylation by TGFβ was analyzed and the effect of the ADAM inhibitors was also examined. Nuclear translocation of HB-EGF-CTF by shedding through ADAM activated by TGFβ was also analyzed. EGFR transactivation, HB-EGF-CTF nuclear translocation, and cell growth were examined under the condition of ADAM17 knockdown.Result: TGFβ-induced EGFR phosphorylation of which ADAM inhibitors were able to inhibit. TGFβ induced shedding of proHB-EGF allowing HB-EGF-CTF to translocate to the nucleus. ADAM inhibitors blocked this nuclear translocation. TGFβ enhanced gastric cancer cell growth and ADAM inhibitors suppressed this effect. EGFR phosphorylation, HB-EGF-CTF nuclear translocation, and cell growth were suppressed in ADAM17 knockdown cells.Conclusion: HB-EGF-CTF nuclear translocation and EGFR transactivation from proHB-EGF shedding mediated by ADAM17 activated by TGFβ might be an important pathway of gastric cancer cell proliferation by TGFβ. 相似文献
268.
Kazuya Sugiyama Hiromi Matsuo Makoto Okano Kunihiro Matsumoto 《Biochemical and biophysical research communications》2010,398(1):118-124
Delta family proteins are transmembrane molecules that bind Notch receptors and activate downstream signaling events in neighboring cells. In addition to serving as Notch ligands, Notch-independent roles for Delta have been suggested but are not fully understood. Here, we demonstrate a previously unrecognized role for Delta in filopodial actin formation. Delta1 and Delta4, but not Delta3, exhibit filopodial protrusive activity, and this activity is independent of Notch signaling. The filopodial activity of Delta1 does not depend on the PDZ-binding domain at the C-terminus; however, the intracellular membrane-proximal region that is anchored to the plasma membrane plays an important role in filopodial activity. We further identified a Notch-independent role of DeltaD in neuronal cell migration in zebrafish. These findings suggest a possible functional link between Notch-independent filopodial activity of Delta and the control of cell motility. 相似文献
269.
Koji Nobe Hiromi Nobe Hiroko Yoshida Richard J. Paul 《Biochemical and biophysical research communications》2010,399(2):292-299
Fibroblast cells play a central role in the proliferation phase of wound healing processes, contributing to force development. The intracellular signaling pathways regulating this non-muscle contraction are only partially understood. To study the relations between Rho A and contractile responses, constitutively active Rho A (CA-Rho A) fibroblast cells were reconstituted into fibers and the effects of calf serum (CS) on isometric force were studied. CS-induced force in CA-Rho A fibroblast fibers was twice as large as that in wild type (NIH 3T3) fibroblast fibers. During this response, the translocation of Rho A from the cytosol to the membrane was detected by Rho A activity assays and Western blot analysis. Pre-treatment with a Rho specific inhibitor (C3-exoenzyme) suppressed translocation as well as contraction. These results indicate that Rho A activation is essential for fibroblast contraction. The Rho kinase inhibitor (Y27632) inhibited both NIH 3T3 and CA-Rho A fibroblast fiber contractions. Activation of Rho A is thus directly coupled with Rho kinase activity. We conclude that the translocation of Rho A from the cytosol to the membrane and the Rho kinase pathway can regulate wound healing processes mediated by fibroblast contraction. 相似文献
270.
The effects of prostaglandin E2(PGE2) on the degradation of collagen and non-collagenous peptides in clonal osteoblastic MC3T3-E1 cells were investigated by using highly sensitive assay methods for PZ-peptidase, collagenase-like peptidase (CL-peptidase), dipeptidyl-aminopeptidase (DAP), leucine aminopeptidase (LAP), and post-proline cleaving enzyme (PPCE). PGE2, at concentrations of 0.1 to 4.0 micrograms/ml, doubled the PZ-peptidase and CL-peptidase activities in the cells on 24 h culturing in a dose-dependent manner. PGE2, at a concentration of 2.0 micrograms/ml, enhanced the specific activities of PZ-peptidase, CL-peptidase, DAP, LAP, and PPCE for 75 h after the start of PGE2 stimulation. The time dependent changes in PZ-peptidase and CL-peptidase activities showed similar patterns, and 3- and 2-fold increases were seen after 48 h, respectively. The protein and DNA contents gradually increased after addition of PGE2. Since the PZ-peptidase and CL-peptidase, involved in degradation of collagen peptides, were significantly induced by PGE2 in comparison with LAP and PPCE, involved in the degradation of non-collagenous peptides, these results show that PGE2 specifically stimulates induction of collagen catabolizing enzymes in clonal osteoblasts. 相似文献