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41.
Frederick J. Darfler 《In vitro cellular & developmental biology. Plant》1990,26(8):769-778
Summary A protein-free medium, termed ABC, has been developed which essentially eliminates the need for serum proteins. ABC supports
the long-term growth of murine hybridomas as well as other transformed cells of the immune system. The requirement of hybridoma
growth for transferrin has been met by substituting the soluble organo-iron compound, sodium nitroprusside. Substantial improvement
in the growth of hybridomas was afforded by the inclusion of 18 trace elements complexed to disodium ethylene diaminetetraacetate
(EDTA). The medium was further improved by the inclusion of components not found in Ham's F12 medium or by raising the concentrations
of existing low molecular weight components. Murine hybridomas can be cultured routinely in this protein-free medium in an
anchorage-independent manner with doubling times generally under 24 h. Visualized on electrophoretic gels, levels of monoclonal
antibody taken from those cultures often exceeded 80% of the total protein. The medium was also able to support the growth
of HuT 78 and H9 cells as well as certain other transformed cells of the immune system. In addition, normal human peripheral
blood lymphocytes, activated with phytohemagglutinin and cultured with 50 U/ml recombinant interleukin 2, could be grown for
2 wk with a 50-fold expansion over input cell number. 相似文献
42.
43.
Sung Mi Ju Su Jin Lee Dong Hyeon Sin Young-Hee Kang Moo-Ho Won Dong-Joo Kwon Soo Young Choi 《Biochemical and biophysical research communications》2009,387(1):115-1259
Keratinocytes, one of major cell types in the skin, can be induced by TNF-α and IFN-γ to express thymus- and activation-regulated chemokine (TARC/CCL17), which is considered to be a pivotal mediator in the inflammatory responses during the development of inflammatory skin diseases, such as atopic dermatitis (AD). In this study, we examined the effect of 1,2,3,4,6-penta-O-galloyl-β-d-glucose (PGG), isolated from the barks of Juglans mandshurica, on TNF-α/IFN-γ induced CCL17 expression in the human keratinocyte cell line HaCaT. Pretreatment of HaCaT cells with PGG suppressed TNF-α/IFN-γ-induced protein and mRNA expression of CCL17. PGG significantly inhibited TNF-α/IFN-γ-induced NF-κB activation as well as STAT1 activation. Furthermore, pretreatment with PGG resulted in significant reduction in expression of CXCL9, 10, and 11 in the HaCaT cells treated with IFN-γ. These results suggest that PGG may exert anti-inflammatory responses by suppressing TNF-α and/or IFN-γ-induced activation of NF-κB and STAT1 in the keratinocytes and might be a useful tool in therapy of skin inflammatory diseases. 相似文献
44.
FanZHANG Tie-JunFU Shu-LinPENG Zhong-RongLIU Li-ShengDING 《植物学报(英文版)》2005,47(2):251-256
Two new triterpenoids, octanordammar-1,11,13(17)-trien-17-ol-3,16-dione (1) and lup-12-en-15α,19β-diol-3,11-dioxo-28-oic acid (4), as well as 13 known compounds were isolated from the roots of Sanguisorba officinalis L. (Rosaceae). Their structures were determined using spectroscopic methods. 相似文献
45.
Analyses of non-leucine-rich repeat (non-LRR) regions intervening between LRRs in proteins 总被引:1,自引:0,他引:1
Norio Matsushima Tomoko Mikami Takanori Tanaka Hiroki Miyashita Keiko Yamada Yoshio Kuroki 《Biochimica et Biophysica Acta (BBA)/General Subjects》2009
Background
Many proteins have LRR (leucine-rich repeat) units interrupted by non-LRRs which we call IR (non-LRR island region).Methods
We identified proteins containing LRR@IRs (LRRs having IR) by using a new method and then analyzed their natures and distributions.Results
LRR@IR proteins were found in over two hundred proteins from prokaryotes and from eukaryotes. These are divided into twenty-one different protein families. The IRs occur one to four times in LRR regions and range in length from 5 to 11,265 residues. The IR lengths in Fungi adenylate cyclases (acys) range from 5 to 116 residues; there are 22 LRR repeats. The IRs in Leishmania proteophosphoglycans (ppgs) vary from 105 to 11,265 residues. These results indicate that the IRs evolved rapidly. A group of LRR@IR proteins—LRRC17, chondroadherin-like protein, ppgs, and four Pseudomonas proteins—have a super motif consisting of an LRR block and its adjacent LRR@IR region. This indicates that the entire super motif experienced duplication. The sequence analysis of IRs offers functional similarity in some LRR@IR protein families.General significance
This study suggests that various IRs and super motifs provide a great variety of structures and functions for LRRs. 相似文献46.
4-Androstene-3,17-dione-[4-14C] was applied to the leaves of growing pea plants, Pisum sativum. Within a week, 28% of the administered steroid was specifically reduced to testosterone. Part of the testosterone was present in esterified form, and 5α-androstane-3β,17β-diol was also identified as a metabolite, but neither epitestosterone nor estrogens were detected. 相似文献
47.
人白细胞介素18(IL-18)是新近发现的细胞因子之一.研究表明它参与T1辅助细胞介导的细胞免疫.利用RT-PCR技术从人外周血细胞扩增得到了IL-18的cDNA并测定其核酸序列.利用基因重组技术构建IL-18的表达载体,并在大肠杆菌中进行了表达.这为以后进一步研究IL-18的功能奠定了基础. 相似文献
48.
49.
In vitro and in vivo characterization of an interleukin‐15 antagonist peptide by metabolic stability, 99mTc‐labeling,and biological activity assays 下载免费PDF全文
Yunier Rodríguez‐Álvarez Ania Cabrales‐Rico Alejandro Perera‐Pintado Anais Prats‐Capote Hilda E. Garay‐Pérez Osvaldo Reyes‐Acosta Erik Pérez‐García Araceli Chico‐Capote Alicia Santos‐Savio 《Journal of peptide science》2018,24(4-5)
Interleukin (IL)–15 is an inflammatory cytokine that constitutes a validated therapeutic target in some immunopathologies, including rheumatoid arthritis (RA). Previously, we identified an IL‐15 antagonist peptide named [K6T]P8, with potential therapeutic application in RA. In the current work, the metabolic stability of this peptide in synovial fluids from RA patients was studied. Moreover, [K6T]P8 peptide was labeled with 99mTc to investigate its stability in human plasma and its biodistribution pattern in healthy rats. The biological activity of [K6T]P8 peptide and its dimer was evaluated in CTLL‐2 cells, using 3 different additives to improve the solubility of these peptides. The half‐life of [K6T]P8 in human synovial fluid was 5.88 ± 1.73 minutes, and the major chemical modifications included peptide dimerization, cysteinylation, and methionine oxidation. Radiolabeling of [K6T]P8 with 99mTc showed a yield of approximately 99.8%. The 99mTc‐labeled peptide was stable in a 30‐fold molar excess of cysteine and in human plasma, displaying a low affinity to plasma proteins. Preliminary biodistribution studies in healthy Wistar rats suggested a slow elimination of the peptide through the renal and hepatic pathways. Although citric acid, sucrose, and Tween 80 enhanced the solubility of [K6T]P8 peptide and its dimer, only the sucrose did not interfere with the in vitro proliferation assay used to assess their biological activity. The results here presented, reinforce nonclinical characterization of the [K6T]P8 peptide, a potential agent for the treatment of RA and other diseases associated with IL‐15 overexpression. 相似文献
50.
Maria Maddalena Di Fiore Alessandra Santillo Sara Falvo Gabriella Chieffi Baccari Massimo Venditti Federica Di Giacomo Russo Monica Lispi Antimo D’Aniello 《Comptes rendus biologies》2018,341(1):9-15
d-Aspartate (d-Asp) is an endogenous amino acid present in the central nervous system and endocrine glands of various animal taxa. d-Asp is implicated in neurotransmission, physiology of learning, and memory processes. In gonads, it plays a crucial role in sex hormone synthesis. We have investigated the effects of chronic (30 days d-Asp drinking solution) and acute (i.p. injection of 2 μmol/g bw d-Asp) treatments on sex steroid synthesis in rat brain. Furthermore, to verify the direct effect of d-Asp on neurosteroidogenic enzyme activities, brain homogenates were incubated with different substrates (cholesterol, progesterone, or testosterone) with or without the addition of d-Asp. Enzyme activities were measured by evaluating the in vitro conversion rate of (i) cholesterol to progesterone, testosterone, and 17β-estradiol, (ii) progesterone to testosterone and 17β-estradiol, (iii) testosterone to 17β-estradiol. We found that d-Asp oral administration produced an increase of approximately 40% in progesterone, 110% in testosterone, and 35% in 17β-estradiol. Similarly, the results of the acute experiment showed that at 30 min after d-Asp treatment, the progesterone, testosterone, and 17β-estradiol levels increased by 29–35%, and at 8 h they further increased by a 100% increment. In vitro experiments demonstrate that the addition of d-Asp to brain homogenate + substrate induces a significant increase in progesterone, testosterone and 17β-estradiol suggesting that the amino acid upregulates the local activity of steroidogenic enzymes. 相似文献