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排序方式: 共有919条查询结果,搜索用时 15 毫秒
791.
Heon Yung Gee Ikhyun Jun Daniela A. Braun Jennifer A. Lawson Jan Halbritter Shirlee Shril Caleb P. Nelson Weizhen Tan Deborah Stein Ari J. Wassner Michael A. Ferguson Zoran Gucev John A. Sayer Danko Milosevic Michelle Baum Velibor Tasic Min Goo Lee Friedhelm Hildebrandt 《American journal of human genetics》2016,98(6):1228-1234
792.
Investigation of Charge Carrier Behavior in High Performance Ternary Blend Polymer Solar Cells 下载免费PDF全文
Tack Ho Lee Mohammad Afsar Uddin Chengmei Zhong Seo‐Jin Ko Bright Walker Taehyo Kim Yung Jin Yoon Song Yi Park Alan J. Heeger Han Young Woo Jin Young Kim 《Liver Transplantation》2016,6(19)
This study demonstrates high‐performance, ternary‐blend polymer solar cells by modifying a binary blend bulk heterojunction (PPDT2FBT:PC71BM) with the addition of a ternary component, PPDT2CNBT. PPDT2CNBT is designed to have complementary absorption and deeper frontier energy levels compared to PPDT2FBT, while being based on the same polymeric backbone. A power conversion efficiency of 9.46% is achieved via improvements in both short‐circuit current density (JSC) and open‐circuit voltage (VOC). Interestingly, the VOC increases with increasing the PPDT2CNBT content in ternary blends. In‐depth studies using ultraviolet photoelectron spectroscopy and transient absorption spectroscopy indicate that the two polymers are not electronically homogeneous and function as discrete light harvesting species. The structural similarity between PPDT2CNBT and PPDT2FBT allows the merits of a ternary system to be fully utilized to enhance both JSC and VOC without detriment to fill‐factor via minimized disruption of semi‐crystalline morphology of binary PPDT2FBT:PC71BM blend. Further, by careful analysis, charge carrier transport in this ternary blend is clearly verified to follow parallel‐like behavior. 相似文献
793.
The role of macrophage-like cells in the in vitro generation of specific B6D2F1 hybrid anti-parental B6 cytotoxic T lymphocytes (CTL) was investigated by means of silica particles (SIL). Depression of this cell-mediated response resulted from the addition of 12.5 or 25 μg of SIL to mixed F1/parent spleen cell cultuers, and full abrogation resulted from the addition of 125 or 250 μg of SIL. The treatment was effective if applied during the first 48 hr of culture. When treatment was delayed, responsiveness did not decline nor did the lytic function of mature CTL exposed to SIL. Moreover, no depression of the anti-allogeneic cell mediated response resulted from the addition of 250 or 500 μg of SIL to mixed F1/allogeneic instead of F1/parent spleen cell cultures. Abrogation of the F1 hybrid anti-parent response was attributed to SIL-induced impairment of an accessory function presumably exerted by macrophage-like cells during the early phases of responder T cell activation. If so, the F1 anti-parent response was considerably more dependent than the allogeneic response on the integrity of accessory cells. Injection of 5 mg of SIL to donors of responder cells likewise resulted in loss of F1 anti-parent and occasionally of anti-allogeneic in vitro responsiveness. This in vivo effect of SIL was prevented by pretreating mice with the lysosomal stabilizer poly-2-vinylpyridine N-oxide. Because unresponsiveness induced in vivo was not selective for F1 anti-parent responses and lasted for up to 10 days, it may be attributable not only to depletion of accessory macrophages by SIL but also to the induction of suppressor macrophages. 相似文献
794.
The Importance of Confined Sulfur Nanodomains and Adjoining Electron Conductive Pathways in Subreaction Regimes of Li‐S Batteries 下载免费PDF全文
Jungjin Park Eui Tae Kim Chunjoong Kim Jeffrey Pyun Hyung‐Seok Jang Jaeho Shin Jang Wook Choi Kookheon Char Yung‐Eun Sung 《Liver Transplantation》2017,7(19)
Polysulfide dissolution into the electrolyte and poor electric conductivity of elemental sulfur are well‐known origins for capacity fading in lithium–sulfur batteries. Various smart electrode designs have lately been introduced to avoid these fading mechanisms, most of which demonstrate significantly improved cycle life. Nevertheless, an in‐depth understanding on the effect of sulfur microstructure and nanoscale electron transport near sulfur is currently lacking. In this study, the authors report an organized nanocomposite comprising linear sulfur chains and oleylamine‐functionalized reduced graphene oxide (O‐rGO) to achieve robust cycling performance (81.7% retention after 500 cycles) as well as to investigate the reaction mechanism in different regimes, i.e., S8 dissolution, polysulfide conversion, and Li2S formation. In the nanocomposite, linear sulfur chains terminate with 1,3‐diisopropylbenzene are covalently linked to O‐rGO. The comparison with control samples that do not contain either the capping of sulfur chains or O‐rGO reveals the synergistic interplay between both treatments, simultaneously unveiling the distinct roles of confined sulfur nanodomains and their adjoining electron pathways in different reaction regimes. 相似文献
795.
Lee TJ Lee JT Kim SH Choi YH Song KS Park JW Kwon TK 《Journal of cellular biochemistry》2008,103(2):358-368
The prostate-apoptosis-response-gene-4 (Par-4) protein has been shown to function as an effector of cell death in response to various apoptotic stimuli that trigger mitochondria and membrane receptor-mediated cell death pathways. We found that overexpressing Par-4 by stable transfection sensitizes Caki cells to induction of apoptosis by TRAIL and drugs that induce endoplasmic reticulum (ER) stress [thapsigargin (TG), tunicamycin (TU) and etoposide]. Ectopic expression of Par-4 is associated with decreased levels of XIAP protein in TG-treated cells, caused in part by XIAP protein instability and caspase activation. Levels of phospho-Akt are decreased in Caki/Par-4 cells to a significantly greater extent than in Caki/Vector cells by treatment with TG, and this is in turn associated with decreased levels of phospho-PDK1, the kinase upstream of Akt. In conclusion, we provide evidence that ectopic expression of Par-4 sensitizes Caki cells to TG and that XIAP protein instability and inactivation of Akt are important in cellular pathways affected by Par-4. 相似文献
796.
797.
Using proteomics to discover novel biomarkers for fatty liver development and response to CB1R antagonist treatment in an obese mouse model 下载免费PDF全文
Chin‐Chang Chen Tzung‐Yan Lee Ching‐Fai Kwok Yung‐Pei Hsu Kuang‐Chung Shih Yan‐Jie Lin Low‐Tone Ho 《Proteomics》2017,17(1-2)
Over activity of cannabinoid receptor type 1 (CB1R) plays a key role in increasing the incidence of obesity‐induced non‐alcoholic fatty liver disease. Tissue proteome analysis has been applied to investigate the bioinformatics regarding the mode of action and therapeutic mechanism. The aim of this study was to explore the potential pathways altered with CB1R in obesity‐induced fatty liver. Male C57BL/6 mice were fed either a standard chow diet (STD) or a high‐fat diet (HFD) with or without 1‐week treatment of CB1R inverse agonist AM251 at 5 mg/kg. Then, liver tissues were harvested for 2DE analysis and protein profiles were identified by using MALDI‐MS. Results showed that eight of significantly altered protein spots at the level of changes > twofold were overlapped among the three groups, naming major urinary protein 1, ATP synthase subunit β, glucosamine‐fructose‐6‐phosphate aminotransferase 1, zine finger protein 2, s‐adenosylmethionine synthase isoform type‐1, isocitrate dehydrogenase subunit α, epoxide hydrolase 2 and 60S acidic ribosomal protein P0. These identified proteins were involved in glucose/lipid metabolic process, xenobiotic metabolic system, and ATP synthesized process in mitochondria. Based on the findings, we speculated that CB1R blockade might exert its anti‐metabolic disorder effect via improvement of mitochondrial function in hepatic steatosis in HFD condition. 相似文献
798.
Immunoreactivity for γ-aminobutyric acid transaminase (GABA-T), a degradation enzyme for GABA, was localized by immunocytochemistry in the rat neostriatum and the globus pallidus using a monoclonal antibody. Immunoreactivity for GABA-T was found primarily in interneurons and in the neuropilar elements in the neostriatum. Many of GABA-T-immunoreactive neurons were found to display parvalbumin immunoreactivity. This indicates many of the GABA-T-immunoreactive neurons are striatal GABAergic interneurons. Occasionally, GABA-T-immunoreactive glial cells were found. In the globus pallidus, many pallidal neurons also displayed GABA-T immunoreactivity and many of the immunoreactive neurons were seen to express parvalbumin immunoreactivity. Immunoreactivity for GABA-T was also detected in the neuropil of the globus pallidus. The present results indicate the GABAergic interneurons in the neostriatum and a subpopulation of pallidal neurons play an important role in metabolic degradation of GABA in the basal ganglia. 相似文献
799.
Prudence H. Tso Yingchun Wang Lisa Y. Yung Yao Tong Maggie M.K. Lee Yung H. Wong 《Cellular signalling》2013,25(5):1064-1074
Besides serving as signal terminators for G protein pathways, several regulators of G protein signaling (RGS) can also modulate cell proliferation. RGS19 has previously been shown to enhance Akt signaling despite impaired Ras signaling. The present study examines the mechanism by which RGS19 inhibits Ras signaling. In HEK293 cells stably expressing RGS19, serum-induced Ras activation and phosphorylations of Raf/MEK/ERK were significantly inhibited, while cells expressing RGS2, 4, 7, 8, 10, or 20 did not exhibit this inhibitory phenotype. Conversely, siRNA-mediated knockdown of RGS19 enabled partial recovery of serum-induced ERK phosphorylation. Interestingly, two isoforms of the tumor metastasis suppressor Nm23 (H1 and H2) were upregulated in 293/RGS19 cells. As a nucleoside diphosphate kinase, Nm23H1 can phosphorylate the kinase suppressor of Ras (KSR). Elevated levels of phosphorylated KSR were indeed detected in the nuclear fractions of 293/RGS19 cells. Co-immunoprecipitation assays revealed that Nm23H1/2 can form complexes with RGS19, Ras, or KSR. siRNA-mediated knockdown of Nm23H1/2 allowed 293/RGS19 cells to partially recover their ERK responses to serum treatment, while overexpression of Nm23H1/2 in HEK293 cells suppressed the serum-induced ERK response. This study demonstrates that expression of RGS19 can suppress Ras-mediated signaling via upregulation of Nm23. 相似文献
800.
Adam Golebiowski Darren Whitehouse R. Paul Beckett Michael Van Zandt Min Koo Ji Todd R. Ryder Erik Jagdmann Monica Andreoli Yung Lee Ryan Sheeler Bruce Conway Jacek Olczak Marzena Mazur Wojciech Czestkowski Wieslawa Piotrowska Alexandra Cousido-Siah Francesc X. Ruiz Andre Mitschler Hagen Schroeter 《Bioorganic & medicinal chemistry letters》2013,23(17):4837-4841
The Ugi reaction has been successfully applied to the synthesis of novel arginase inhibitors. In an effort to decrease conformational flexibility of the previously reported series of 2-amino-6-boronohexanoic acid (ABH) analogs 1, we designed and synthesized a series of compounds, 2, in which a piperidine ring is linked directly to a quaternary amino acid center. Further improvement of in vitro activity was achieved by adding two carbon bridge in the piperidine ring, that is, tropane analogs 11. These improvements in activity are rationalized by X-ray crystallography analysis, which show that the tropane ring nitrogen atom moves into direct contact with Asp202 (arginase II numbering). The synthetic routes described here enabled the design of novel arginase inhibitors with improved potency and markedly different physico-chemical properties compared to ABH. Compound 11c represents the most in vitro active arginase inhibitor reported to date. 相似文献