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21.
Ya‐Qian Zhang Yaosen Tian Yihan Xiao Lincoln J. Miara Yuichi Aihara Tomoyuki Tsujimura Tan Shi M. C. Scott Gerbrand Ceder 《Liver Transplantation》2020,10(27)
The interfacial instability between a thiophosphate solid electrolyte and oxide cathodes results in rapid capacity fade and has driven the need for cathode coatings. In this work, the stability, evolution, and performance of uncoated, Li2ZrO3‐coated, and Li3B11O18‐coated LiNi0.5Co0.2Mn0.3O2 cathodes are compared using first‐principles computations and electron microscopy characterization. Li3B11O18 is identified as a superior coating that exhibits excellent oxidation/chemical stability, leading to substantially improved performance over cells with Li2ZrO3‐coated or uncoated cathodes. The chemical and structural origin of the different performance is interpreted using different microscopy techniques which enable the direct observation of the phase decomposition of the Li2ZrO3 coating. It is observed that Li is already extracted from the Li2ZrO3 in the first charge, leading to the formation of ZrO2 nanocrystallites with loss of protection of the cathode. After 50 cycles separated (Co, Ni)‐sulfides and Mn‐sulfides can be observed within the Li2ZrO3‐coated material. This work illustrates the severity of the interfacial reactions between a thiophosphate electrolyte and oxide cathode and shows the importance of using coating materials that are absolutely stable at high voltage. 相似文献
22.
23.
Small proline-rich protein 1A is a gp130 pathway- and stress-inducible cardioprotective protein 下载免费PDF全文
Pradervand S Yasukawa H Muller OG Kjekshus H Nakamura T St Amand TR Yajima T Matsumura K Duplain H Iwatate M Woodard S Pedrazzini T Ross J Firsov D Rossier BC Hoshijima M Chien KR 《The EMBO journal》2004,23(22):4517-4525
The interleukin-6 cytokines, acting via gp130 receptor pathways, play a pivotal role in the reduction of cardiac injury induced by mechanical stress or ischemia and in promoting subsequent adaptive remodeling of the heart. We have now identified the small proline-rich repeat proteins (SPRR) 1A and 2A as downstream targets of gp130 signaling that are strongly induced in cardiomyocytes responding to biomechanical/ischemic stress. Upregulation of SPRR1A and 2A was markedly reduced in the gp130 cardiomyocyte-restricted knockout mice. In cardiomyocytes, MEK1/2 inhibitors prevented SPRR1A upregulation by gp130 cytokines. Furthermore, binding of NF-IL6 (C/EBPbeta) and c-Jun to the SPRR1A promoter was observed after CT-1 stimulation. Histological analysis revealed that SPRR1A induction after mechanical stress of pressure overload was restricted to myocytes surrounding piecemeal necrotic lesions. A similar expression pattern was found in postinfarcted rat hearts. Both in vitro and in vivo ectopic overexpression of SPRR1A protected cardiomyocytes against ischemic injury. Thus, this study identifies SPRR1A as a novel stress-inducible downstream mediator of gp130 cytokines in cardiomyocytes and documents its cardioprotective effect against ischemic stress. 相似文献
24.
Fujita T Makishima D Akiyama K Hayashi H 《Bioscience, biotechnology, and biochemistry》2002,66(8):1697-1705
New convulsive compounds, brasiliamides A (1) and B (2), were isolated by activity-guided fractionation from okara fermented with a soil isolate of Penicillium brasilianum Batista JV-379. Their structures were elucidated on the basis of spectral and chemical evidence and by X-ray crystallography of the hydrogenated product of 2. In the 1H- and 13C-NMR spectra of 2, the signals were complicated, all being doubled or broadened in several deuterated solvents at room temperature. The conformational change of 2 was clarified as the rotational isomerization of amide bonds in solution by NMR measurements at various temperatures. Four rotamers of 2 at two amide bonds were presented at -60 degrees C in CDCl3, whereas only two isomers were apparent at room temperature, owing to rapid rotation of one of the amide bonds. Brasiliamides A and B respectively showed convulsive activity against silkworms with ED50 values of 300 and 50 microg/g of diet. 相似文献
25.
Yuriko Uehara Katsutoshi Oda Yuji Ikeda Takahiro Koso Shingo Tsuji Shogo Yamamoto Kayo Asada Kenbun Sone Reiko Kurikawa Chinami Makii Otoe Hagiwara Michihiro Tanikawa Daichi Maeda Kosei Hasegawa Shunsuke Nakagawa Osamu Wada-Hiraike Kei Kawana Masashi Fukayama Keiichi Fujiwara Tetsu Yano Yutaka Osuga Tomoyuki Fujii Hiroyuki Aburatani 《PloS one》2015,10(6)
Ovarian clear cell carcinoma (CCC) is generally associated with chemoresistance and poor clinical outcome, even with early diagnosis; whereas high-grade serous carcinomas (SCs) and endometrioid carcinomas (ECs) are commonly chemosensitive at advanced stages. Although an integrated genomic analysis of SC has been performed, conclusive views on copy number and expression profiles for CCC are still limited. In this study, we performed single nucleotide polymorphism analysis with 57 epithelial ovarian cancers (31 CCCs, 14 SCs, and 12 ECs) and microarray expression analysis with 55 cancers (25 CCCs, 16 SCs, and 14 ECs). We then evaluated PIK3CA mutations and ARID1A expression in CCCs. SNP array analysis classified 13% of CCCs into a cluster with high frequency and focal range of copy number alterations (CNAs), significantly lower than for SCs (93%, P < 0.01) and ECs (50%, P = 0.017). The ratio of whole-arm to all CNAs was higher in CCCs (46.9%) than SCs (21.7%; P < 0.0001). SCs with loss of heterozygosity (LOH) of BRCA1 (85%) also had LOH of NF1 and TP53, and LOH of BRCA2 (62%) coexisted with LOH of RB1 and TP53. Microarray analysis classified CCCs into three clusters. One cluster (CCC-2, n = 10) showed more favorable prognosis than the CCC-1 and CCC-3 clusters (P = 0.041). Coexistent alterations of PIK3CA and ARID1A were more common in CCC-1 and CCC-3 (7/11, 64%) than in CCC-2 (0/10, 0%; P < 0.01). Being in cluster CCC-2 was an independent favorable prognostic factor in CCC. In conclusion, CCC was characterized by a high ratio of whole-arm CNAs; whereas CNAs in SC were mainly focal, but preferentially caused LOH of well-known tumor suppressor genes. As such, expression profiles might be useful for sub-classification of CCC, and might provide useful information on prognosis. 相似文献
26.
Kawase T Okuda K Saito Y Amizuka N Suzuki H Yoshie H 《In vitro cellular & developmental biology. Animal》2005,41(5-6):171-176
Summary Platelet-rich plasma (PRP) has been used to promote periodontal regeneration following the premise that constituent transforming
growth factor-β1 (TGF-β1) and platelet-derived growth factor-AB will stimulate cell proliferation at the site of application.
In previous studies, we demonstrated that PRP mimics TGF-β1 to modulate proliferation in a cell type-specific manner, that
fibrin clot formation by PRP upregulates type I collagen, and that an unidentified factor(s) in PRP increases alkaline phosphatase
(ALP) activity in human periodontal ligament (PDL) cell cultures. We have now examined the effects of PRP on in vitro mineralization.
Platelet-rich plasma and PDL cells were prepared from human adult volunteers or rats. After 20 d of continuous treatment with
PRP in dexamethazone (Dex)-containing osteogenic medium, PRP time dependently promoted mineralization by rat PDL cells but
failed to fully induce the osteoblastic phenotype. Furthermore, when human PDL cells were induced to increase ALP activity
in osteogenic medium that lacked Dex, a condition that should delay (or suppress) osteoblastic differentiation, transmission
electron microscopy revealed that mineralized spicules were initially deposited onto PRP-derived platelet aggregates. Taken
together with our previous data, these findings suggest that PRP provides platelet aggregates as nuclei to initiate mineralization
while stimulating PDL cell proliferation, differentiation, and collagen production. The combination of these effects may effectively
mediate PRP's ability to promote regeneration of periodontal tissue, including skeletal tissue, at the site of injury. 相似文献
27.
Interaction of KAI1 on tumor cells with DARC on vascular endothelium leads to metastasis suppression 总被引:12,自引:0,他引:12
Bandyopadhyay S Zhan R Chaudhuri A Watabe M Pai SK Hirota S Hosobe S Tsukada T Miura K Takano Y Saito K Pauza ME Hayashi S Wang Y Mohinta S Mashimo T Iiizumi M Furuta E Watabe K 《Nature medicine》2006,12(8):933-938
CD82, also known as KAI1, was recently identified as a prostate cancer metastasis suppressor gene on human chromosome 11p1.2 (ref. 1). The product of CD82 is KAI1, a 40- to 75-kDa tetraspanin cell-surface protein also known as the leukocyte cell-surface marker CD82 (refs. 1,2). Downregulation of KAI1 has been found to be clinically associated with metastatic progression in a variety of cancers, whereas overexpression of CD82 specifically suppresses tumor metastasis in various animal models. To define the mechanism of action of KAI1, we used a yeast two-hybrid screen and identified an endothelial cell-surface protein, DARC (also known as gp-Fy), as an interacting partner of KAI1. Our results indicate that the cancer cells expressing KAI1 attach to vascular endothelial cells through direct interaction between KAI1 and DARC, and that this interaction leads to inhibition of tumor cell proliferation and induction of senescence by modulating the expression of TBX2 and p21. Furthermore, the metastasis-suppression activity of KAI1 was significantly compromised in DARC knockout mice, whereas KAI1 completely abrogated pulmonary metastasis in wild-type and heterozygous littermates. These results provide direct evidence that DARC is essential for the function of CD82 as a suppressor of metastasis. 相似文献
28.
Reproductive stages of 5 japonica, 9 indica, and 2 javanica cultivars of rice ( Oryza sativa L.) were provided to compare the contents of protein for cytosolic glutamine synthetase (GS1; EC 6.3.1.2) in the lowest position of the attached leaf blade (position 6 from the primary leaf) and those for NADH-glutamate synthase (NADH-GOGAT; EC 1.4.1.14) in non-green portion of the expanding 10th leaf blade. Some of the indica cultivars, including Kasalath, contained GS1 protein twice as high as other japonica and javanica cultivars based on total leaf nitrogen. Most of the indica cultivars, on the other hand, contained less NADH-GOGAT protein than japonica and javanica cultivars. Immunostaining proved that GS1 protein was located in vascular tissues of the leaf blades of Kasalath, which was identical to our previous results with a japonica cultivar [Sakurai et al. (1996) Planta 200: 306–311]. Although relative contents of GS1 protein in the leaf blade of Kasalath increased as a function of leaf age, GS1 activity remained relatively constant. In addition, Kasalath showed lower activity than other japonica and javanica cultivars, especially during leaf expansion. GS1 activity, based on GS1 protein amount, changed during the life span of the leaf blade and we thus assume that GS1 activity was modulated post-translationally in rice leaves. 相似文献
29.
Tomoyuki Tsuneya Masakazu Ishihara Haruyasu Shiota Minoru Shiga 《Bioscience, biotechnology, and biochemistry》2013,77(11):2495-2502
Steam distilled oil of quince fruit (Cydonia oblonga Mill.=C. vulgaris Pers., marmelo in Japanese) was analyzed by gas chromatography and gas chromatography-mass spectrometry. Sixty-two compounds, 2 hydrocarbons, 13 esters, 11 alcohols, 11 aldehydes, 11 ketones, 5 lactones and 9 miscellaneous compounds, were identified. Of them, the chemical structures of two new oxide compounds, trans- and cis-3-methyl-5-[(E)-3′-methyl-13′-butadien-1′-yl]tetrahydrofuran, were elucidated by instrumental analyses. 相似文献
30.
Umemoto N Ohnuma T Urpilainen H Yamamoto T Numata T Fukamizo T 《Bioscience, biotechnology, and biochemistry》2012,76(4):778-784
Tryptophan residues located in the substrate-binding cleft of a class V chitinase from Nicotiana tabacum (NtChiV) were mutated to alanine and phenylalanine (W190F, W326F, W190F/W326F, W190A, W326A, and W190A/W326A), and the mutant enzymes were characterized to define the role of the tryptophans. The mutations of Trp326 lowered thermal stability by 5-7 °C, while the mutations of Trp190 lowered stability only by 2-4 °C. The Trp326 mutations strongly impaired enzymatic activity, while the effects of the Trp190 mutations were moderate. The experimental data were rationalized based on the crystal structure of NtChiV in a complex with (GlcNAc)(4), in which Trp190 is exposed to the solvent and involved in face-to-face stacking interaction with the +2 sugar, while Trp326 is buried inside but interacts with the -2 sugar through hydrophobicity. HPLC analysis of anomers of the enzymatic products suggested that Trp190 specifically recognizes the β-anomer of the +2 sugar. The strong effects of the Trp326 mutations on activity and stability suggest multiple roles of the residue in stabilizing the protein structure, in sugar residue binding at subsite -2, and probably in maintaining catalytic efficiency by providing a hydrophobic environment for proton donor Glu115. 相似文献