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21.
From leaves and twigs of Ixora chinensis, two new iridoid glucosides, ixoroside (1) and ixoside (7,8-dehydroforsythide) (2) along with known geniposidic acid (3) have been isolated and their structures have been established. 相似文献
22.
Solaniol, a Toxic Metabolite of Fusarium solani 总被引:1,自引:6,他引:1
Kenji Ishii Kosei Sakai Yoshio Ueno Hiroshi Tsunoda Makoto Enomoto 《Applied microbiology》1971,22(4):718-720
Fusarium solani M-1-1 isolated from moldy bean hulls produces T-2 toxin, diacetoxyscirpenol, and a new toxic trichothecene, solaniol, in Czapek-Dox-peptone medium. 相似文献
23.
Sato M Sano H Iwaki D Kudo K Konishi M Takahashi H Takahashi T Imaizumi H Asai Y Kuroki Y 《Journal of immunology (Baltimore, Md. : 1950)》2003,171(1):417-425
The lung collectin surfactant protein A (SP-A) has been implicated in the regulation of pulmonary host defense and inflammation. Zymosan induces proinflammatory cytokines in immune cells. Toll-like receptor (TLR)2 has been shown to be involved in zymosan-induced signaling. We first investigated the interaction of TLR2 with zymosan. Zymosan cosedimented the soluble form of rTLR2 possessing the putative extracellular domain (sTLR2). sTLR2 directly bound to zymosan with an apparent binding constant of 48 nM. We next examined whether SP-A modulated zymosan-induced cellular responses. SP-A significantly attenuated zymosan-induced TNF-alpha secretion in RAW264.7 cells and alveolar macrophages in a concentration-dependent manner. Although zymosan failed to cosediment SP-A, SP-A significantly reduced zymosan-elicited NF-kappaB activation in TLR2-transfected human embryonic kidney 293 cells. Because we have shown that SP-A binds to sTLR2, we also examined whether SP-A affected the binding of sTLR2 to zymosan. SP-A significantly attenuated the direct binding of sTLR2 to zymosan in a concentration-dependent fashion. From these results, we conclude that 1) TLR2 directly binds zymosan, 2) SP-A can alter zymosan-TLR2 interaction, and 3) SP-A down-regulates TLR2-mediated signaling and TNF-alpha secretion stimulated by zymosan. This study supports an important role of SP-A in controlling pulmonary inflammation caused by microbial pathogens. 相似文献
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Ando Y Liang Y Ishigaki S Niwa J Jiang Y Kobayashi Y Yamamoto M Doyu M Sobue G 《Neurochemical research》2003,28(6):839-846
Amyotrophic lateral sclerosis is characterized by selective motor neuron degeneration. An apoptotic pathway is thought to be involved. It is difficult, however, to analyze the molecular pathogenic mechanism in single motor neurons because of complexity in the neural tissue, which consists of multiple lineages of cells neighboring motor neurons. We quantified the caspase-1 and -3 mRNA in single motor neurons and neighboring glial cells isolated from the spinal ventral horn of mutant SOD1 transgenic (Tg) mice and littermates. Motor neurons and neighboring glial cells were isolated from spinal sections by laser microdissection, and the mRNAs were quantified by RT-PCR. In the Tg mice, caspase-1 mRNA was first upregulated in motor neurons and second in glial cells. The caspase-3 mRNA was increased in motor neurons following the caspase-1 mRNA. These results indicated that caspase-1 and -3 mRNAs are differentially upregulated in motor neurons and glial cells of the Tg mice, and that mRNAs in isolated cells can be accurately assessed using our procedures. 相似文献
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Naoki Kamada Kaori Tano Akiko Oyabu Yoshio Imura Naoko Narita Yasura Tashiro Atsuko Uchida Yoshihiro Komada Masaaki Narita 《International journal of peptide research and therapeutics》2010,16(2):55-61
We recently identified a novel 40-amino acid neuropeptide designated manserin from the rat brain (Yajima in NeuroReport 15:
1755–1759, 2004). Manserin is highly expressed in pituitary and hypothalamic nuclei, which suggests that it plays a role in
the endocrine system. In this study, we employed immunohistochemical methods to investigate the presence of manserin in rat
adrenal glands, as well as its regulation by physical stress. Immunohistochemical analysis using anti-manserin antibody showed
that manserin is present in the rat adrenal medulla but not in the cortex. When the colocalization of manserin and phenylethanolamine
N-methyltransferase (PNMT), an epinephrine-synthesizing enzyme, was examined, virtually all PNMT-positive cells expressed manserin.
Interestingly, the immunoreactivity of manserin was significantly increased when the rats were exposed to water-immersion
restraint stress. These results demonstrate for the first time that adrenal manserin, a novel neuropeptide, may have a potential
physiological role under stress-inducing conditions. 相似文献
29.
Genotoxic stress exerts biological activity by activating downstream effectors, including the p53 tumor suppressor. p53 regulates cell-cycle checkpoint and induction of apoptosis in response to DNA damage; however, molecular mechanisms responsible for committing to these distinct functions remain to be elucidated. Recent studies demonstrated that phosphorylation of p53 at Ser46 is associated with induction of p53AIP1 expression, resulting in commitment to apoptotic cell death. In this regard, the role for Ser46 kinases in p53-dependent apoptosis has been established; however, the kinases responsible for Ser46 phosphorylation have yet to be identified. Here, we demonstrate that the dual-specificity tyrosine-phosphorylation-regulated kinase 2 (DYRK2) directly phosphorylates p53 at Ser46. Upon exposure to genotoxic stress, DYRK2 translocates into the nucleus for Ser46 phosphorylation. Consistent with these results, DYRK2 induces p53AIP1 expression and apoptosis in a Ser46 phosphorylation-dependent manner. These findings indicate that DYRK2 regulates p53 to induce apoptosis in response to DNA damage. 相似文献
30.
Thomas Regnier Diganta Sarma Koushi Hidaka Usman Bacha Ernesto Freire Yoshio Hayashi Yoshiaki Kiso 《Bioorganic & medicinal chemistry letters》2009,19(10):2722-2727
A series of trifluoromethyl, benzothiazolyl or thiazolyl ketone-containing peptidic compounds as SARS-CoV 3CL protease inhibitors were developed and their potency was evaluated by in vitro protease inhibitory assays. Three candidates had encouraging results for the development of new anti-SARS compounds. 相似文献