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891.
892.
Ravichandran N. Murugan Jung-Eun Park Dan Lim Mija Ahn Chaejoon Cheong Taeho Kwon Ky-Youb Nam Sun Ho Choi Bo Yeon Kim Do-Young Yoon Michael B. Yaffe Dae-Yeul Yu Kyung S. Lee Jeong Kyu Bang 《Bioorganic & medicinal chemistry》2013,21(9):2623-2634
The polo-box domain (PBD) of polo-like kinase 1 (Plk1) is essentially required for the function of Plk1 in cell proliferation. The availability of the phosphopeptide-binding pocket on PBD provides a unique opportunity to develop novel protein–protein interaction inhibitors. Recent identification of a minimal 5-residue-long phosphopeptide, PLHSpT, as a Plk1 PBD-specific ligand has led to the development of several peptide-based inhibitors, but none of them is cyclic peptide. Through the combination of single-peptoid mimics and thio-ether bridged cyclization, we successfully demonstrated for the first time two cyclic peptomers, PL-116 and PL-120, dramatically improved the binding affinity without losing mono-specificity against Plk1 PBD in comparison with the linear parental peptide, PLHSpT. These cyclic peptomers could serve as promising templates for future drug designs to inhibit Plk1 PBD. 相似文献
893.
为进一步阐明盐生植物白刺耐盐性与多胺的关系,通过水培试验研究了叶面喷施亚精胺(Spd)对不同浓度NaCl胁迫下西伯利亚白刺幼苗叶片丙二醛(MDA)和超氧阴离子(O2)产生速率,以及抗氧化物酶系统和根系活力的影响.结果表明:叶面喷施0.1 mmol·L1 Spd 5 d后,可显著提高100和200 mmol·L1 NaCl胁迫下白刺幼苗叶片超氧化物歧化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT)的活性以及根系活力,降低了叶片MDA含量和O2的产生速率;而在0、50、300 mmol·L-1 NaC1处理下,外施Spd对白刺幼苗叶片上述指标无显著影响.研究结果证实,在100~200 mmol·L-1 NaCl胁迫范围内,外施亚精胺可能通过增强体内保护酶活性来显著降低活性氧水平,有效减轻盐胁迫对盐生植物白刺幼苗造成的过氧化伤害,从而增强白刺对盐环境的适应性. 相似文献
894.
Jeanie L. Y. Cheong Peter J. Anderson Gehan Roberts Alice C. Burnett Katherine J. Lee Deanne K. Thompson Carly Molloy Michelle Wilson-Ching Alan Connelly Marc L. Seal Stephen J. Wood Lex W. Doyle 《PloS one》2013,8(10)
Objectives
Extremely preterm (EP) survivors have smaller brains, lower IQ, and worse educational achievement than their term-born peers. The contribution of smaller brain size to the IQ and educational disadvantages of EP is unknown. This study aimed (i) to compare brain volumes from multiple brain tissues and structures between EP-born (<28weeks) and term-born (≥37weeks) control adolescents, (ii) to explore the relationships of brain tissue volumes with IQ and basic educational skills and whether this differed by group, and (iii) to explore how much total brain tissue volume explains the underperformance of EP adolescents compared with controls.Methods
Longitudinal cohort study of 148 EP and 132 term controls born in Victoria, Australia in 1991-92. At age 18, magnetic resonance imaging-determined brain volumes of multiple tissues and structures were calculated. IQ and educational skills were measured using the Wechsler Abbreviated Scale of Intelligence (WASI) and the Wide Range Achievement Test(WRAT-4), respectively.Results
Brain volumes were smaller in EP adolescents compared with controls (mean difference [95% confidence interval] of -5.9% [-8.0, -3.7%] for total brain tissue volume). The largest relative differences were noted in the thalamus and hippocampus. The EP group had lower IQs(-11.9 [-15.4, -8.5]), spelling(-8.0 [-11.5, -4.6]), math computation(-10.3 [-13.7, -6.9]) and word reading(-5.6 [-8.8, -2.4]) scores than controls; all p-values<0.001. Volumes of total brain tissue and other brain tissues and structures correlated positively with IQ and educational skills, a relationship that was similar for both the EP and controls. Total brain tissue volume explained between 20-40% of the IQ and educational outcome differences between EP and controls.Conclusions
EP adolescents had smaller brain volumes, lower IQs and poorer educational performance than controls. Brain volumes of multiple tissues and structures are related to IQ and educational outcomes. Smaller total brain tissue volume is an important contributor to the cognitive and educational underperformance of adolescents born EP. 相似文献895.
Vui King Vincent-Chong Arif Anwar Lee Peng Karen-Ng Sok Ching Cheong Yi-Hsin Yang Padmaja Jayaprasad Pradeep Zainal Ariff Abdul Rahman Siti Mazlipah Ismail Zuraiza Mohamad Zaini Narayanan Prepageran Thomas George Kallarakkal Anand Ramanathan Nur Aaina Binti Mohd Mohayadi Nurul Shielawati Binti Mohamed Rosli Wan Mahadzir Wan Mustafa Mannil Thomas Abraham Keng Kiong Tay Rosnah Binti Zain 《PloS one》2013,8(2)
896.
897.
报道了豆科Leguminosae昆仑岩黄耆Hedysarum krassnovii B.Fedtsch.在中国的分布。昆仑岩黄耆与近缘种红花岩黄耆H.multijugum Maxim.形态易混淆,但以其小叶3-9×3-7mm;旗瓣倒卵形,顶端凹陷约2mm深;翼瓣狭披针形;龙骨瓣近半圆形或矩圆形;花萼二唇彤;荚果具1-2节荚等性状易于区分。另外,此二种的物候期、生境及地理分布亦有区别。 相似文献
898.
A novel transglycosylation reaction from sucrose to l-ascorbic acid by a recombinant sucrose phosphorylase from Bifidobacterium longum was used to produce a stable l-ascorbic acid derivative. The major product was detected by HPLC, and confirmed to be 2-O-α-d-glucopyranosyl-l-ascorbic acid by LC-MS/MS analysis. 相似文献
899.
Moon JS Kim HK Koo HC Joo YS Nam HM Park YH Kang MI 《Applied microbiology and biotechnology》2007,75(5):989-998
Based on our previous study evaluating the in vivo cure efficacy of chitosan on bovine mastitis, a more water-soluble chitosan-oligosaccharide
(OCHT) with a high degree of deacetylation and low molecular weight was prepared to obtain high antibiotic efficacy. The growth
of Staphylococcus aureus isolated from bovine mastitis was inhibited within 10 min of treatment with OCHT in concentrations ranging from 0.0001 to
0.5%. Additionally, electron microscopic observation indicated that the surface of the OCHT-treated bacteria was expanded,
distorted, and lysed compared to that of the control bacteria. In mice, the proportion of monocytes was elevated, and the
levels of interleukin-6 and interferon-γ sharply increased l h after the peritoneal inoculation of the OCHT (0.5 to 1 mg per
mouse). Mice challenged intraperitoneally with S. aureus (2.5 × 108 colony forming units) after oral treatment with OCHT (0.5 to 2 mg per day) for 7 days showed a higher survival rate (70–100%)
than that of the control (10%). We suggest that the OCHT prepared in this study is a potential agent for the prevention and
treatment of bovine mastitis based on its strong antibacterial activity against S. aureus as well as the immunostimulative effect it exhibits on murine infection by S. aureus.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
900.
Zhenzhen Mo Jia Yang Alex Cheong Lirong Xiang Minh T. N. Le Andrew Grimson Daniel Xin Zhang 《Cell proliferation》2021,54(1)
Metastasis refers to the progressive dissemination of primary tumour cells and their colonization of other tissues and is associated with most cancer‐related mortalities. The disproportional and systematic distribution pattern of distant metastasis in different cancers has been well documented, as is termed metastatic organotropism, a process orchestrated by a combination of anatomical, pathophysiological, genetic and biochemical factors. Extracellular vesicles (EVs), nanosized cell‐derived membrane‐bound particles known to mediate intercellular communication, are now considered crucial in organ‐specific metastasis. Here, we review and summarize recent findings regarding EV‐associated organotropic metastasis as well as some of the general mechanisms by which EVs contribute to this important process in cancer and provide a future perspective on this emerging topic. We highlight studies that demonstrate a role of tumour‐derived EVs in organotropic metastasis via pre‐metastatic niche modulation. The bioactive cargo carried by EVs is of diagnostic and prognostic values, and counteracting the functions of such EVs may be a novel therapeutic strategy targeting metastasis. Further investigations are warranted to better understand the functions and mechanisms of EVs in organotropic metastasis and accelerate the relevant clinical translation. 相似文献