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951.
Isao Tsutsui Tatsuo Miyoshi Halethichanok Sukchai Piyarat Pinphoo Dusit Aue-umneoy Chonlada Meeanan Jaruwan Songphatkaew Sirimas Klomkling Iori Yamaguchi Monthon Ganmanee Hiroyuki Sudo Kaoru Hamano 《PloS one》2015,10(4)
The unique beauty of spherical aggregation forming algae has attracted much attention from both the scientific and lay communities. Several aegagropilous seaweeds have been identified to date, including the plants of genus Cladophora and Chaetomorpha. However, this phenomenon remains poorly understood. In July 2013, a mass occurrence of spherical Cladophora aggregations was observed in a salt field reservoir in Central Thailand. The aims of the present study were to describe the habitat of the spherical aggregations and confirm the species. We performed a field survey, internal and external morphological observations, pyrenoid ultrastructure observations, and molecular sequence analysis. Floating spherical Cladophora aggregations (1–8 cm in diameter) were observed in an area ~560 m2, on the downwind side of the reservoir where there was water movement. Individual filaments in the aggregations were entangled in each other; consequently, branches growing in different directions were observed within a clump. We suggest that water movement and morphological characteristics promote the formation of spherical aggregations in this species. The molecular sequencing results revealed that the study species was highly homologous to both C. socialis and C. coelothrix. However, the diameter of the apical cells in the study species was less than that of C. coelothrix. The pyrenoid ultrastructure was more consistent with that of C. socialis. We conclude that the study species is C. socialis. This first record of spherical aggregations in this species advances our understanding of these formations. However, further detailed physical measurements are required to fully elucidate the mechanism behind these spherical formations. 相似文献
952.
953.
Nitin Patel Tatsuo Itakura Shinwu Jeong Chun-Peng Liao Pradip Roy-Burman Ebrahim Zandi Susan Groshen Jacek Pinski Gerhard A. Coetzee Mitchell E. Gross M. Elizabeth Fini 《PloS one》2015,10(2)
Prostate cancer (PCa) is the second-leading cause of cancer-related mortality, after lung cancer, in men from developed countries. In its early stages, primary tumor growth is dependent on androgens, thus generally can be controlled by androgen deprivation therapy (ADT). Eventually however, the disease progresses to castration-resistant prostate cancer (CRPC), a lethal form in need of more effective treatments. G-protein coupled receptors (GPCRs) comprise a large clan of cell surface proteins that have been implicated as therapeutic targets in PCa growth and progression. The findings reported here provide intriguing evidence of a role for the newly characterized glutamate family member GPR158 in PCa growth and progression. We found that GPR158 promotes PCa cell proliferation independent of androgen receptor (AR) functionality and that this requires its localization in the nucleus of the cell. This suggests that GPR158 acts by mechanisms different from other GPCRs. GPR158 expression is stimulated by androgens and GPR158 stimulates AR expression, implying a potential to sensitize tumors to low androgen conditions during ADT via a positive feedback loop. Further, we found GPR158 expression correlates with a neuroendocrine (NE) differentiation phenotype and promotes anchorage-independent colony formation implying a role for GPR158 in therapeutic progression and tumor formation. GPR158 expression was increased at the invading front of prostate tumors that formed in the genetically defined conditional Pten knockout mouse model, and co-localized with elevated AR expression in the cell nucleus. Kaplan-Meier analysis on a dataset from the Memorial Sloan Kettering cancer genome portal showed that increased GPR158 expression in tumors is associated with lower disease-free survival. Our findings strongly suggest that pharmaceuticals targeting GPR158 activities could represent a novel and innovative approach to the prevention and management of CRPC. 相似文献
954.
Various factors that are important for proper hearing have been identified, including serum levels of zinc. Here we investigated whether epigenetic regulatory pathways, which can be modified by environmental factors, could modulate hearing. RT-PCR detected expression of genes encoding DNA methyltransferase and histone deacetylase (Hdac) in the postnatal as well as adult mouse auditory epithelium. DBA/2J mice, which are a model for progressive hearing loss, were injected subcutaneously with one or a combination of the following reagents: <smallcaps>L</smallcaps>-methionine as a methyl donor, valproic acid as a pan-Hdac inhibitor, and folic acid and vitamin B12 as putative factors involved in age-related hearing loss. The mice were treated from ages 4 to 12 weeks (N ≥ 5), and auditory brainstem response (ABR) thresholds were measured at 8, 16, and 32 kHz. Treatment of the mice with a combination of <smallcaps>L</smallcaps>-methionine and valproic acid (M+V) significantly reduced the increase in the ABR threshold at 32 kHz. Treatment with any of these reagents individually produced no such effect. Microarray analyses detected 299 gene probes that were significantly up- or down-regulated in the cochleae of mice treated with M+V compared with the control vehicle-treated mice. Quantitative RT-PCR confirmed significant up-regulation of a zinc importer gene, Zip4, in the cochleae of mice treated with M+V. Immunohistochemistry demonstrated an intense Zip4 signal in cochlear tissues such as the lateral wall, organ of Corti, and spiral ganglion. Finally, mice treated with the Zip4 inducer (–)-epigallocatechin-3-O-gallate showed a significant reduction in the increase of the ABR threshold at 32 kHz and up-regulation of Zip4 expression in the cochlea. This study suggests that epigenetic regulatory pathways can modify auditory function and that zinc intake in the cochlea via Zip4 mediates maintenance of mammalian hearing. 相似文献
955.
The M-Ras-RA-GEF-2-Rap1 pathway mediates tumor necrosis factor-alpha dependent regulation of integrin activation in splenocytes
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Yoshikawa Y Satoh T Tamura T Wei P Bilasy SE Edamatsu H Aiba A Katagiri K Kinashi T Nakao K Kataoka T 《Molecular biology of the cell》2007,18(8):2949-2959
The Rap1 small GTPase has been implicated in regulation of integrin-mediated leukocyte adhesion downstream of various chemokines and cytokines in many aspects of inflammatory and immune responses. However, the mechanism for Rap1 regulation in the adhesion signaling remains unclear. RA-GEF-2 is a member of the multiple-member family of guanine nucleotide exchange factors (GEFs) for Rap1 and characterized by the possession of a Ras/Rap1-associating domain, interacting with M-Ras-GTP as an effector, in addition to the GEF catalytic domain. Here, we show that RA-GEF-2 is specifically responsible for the activation of Rap1 that mediates tumor necrosis factor-alpha (TNF-alpha)-triggered integrin activation. In BAF3 hematopoietic cells, activated M-Ras potently induced lymphocyte function-associated antigen 1 (LFA-1)-mediated cell aggregation. This activation was totally abrogated by knockdown of RA-GEF-2 or Rap1. TNF-alpha treatment activated LFA-1 in a manner dependent on M-Ras, RA-GEF-2, and Rap1 and induced activation of M-Ras and Rap1 in the plasma membrane, which was accompanied by recruitment of RA-GEF-2. Finally, we demonstrated that M-Ras and RA-GEF-2 were indeed involved in TNF-alpha-stimulated and Rap1-mediated LFA-1 activation in splenocytes by using mice deficient in RA-GEF-2. These findings proved a crucial role of the cross-talk between two Ras-family GTPases M-Ras and Rap1, mediated by RA-GEF-2, in adhesion signaling. 相似文献
956.
957.
Katayama K Shimazaki K Tazaki H Hasa Y Miyoshi M Koshino H Furuki T Nabeta K 《Bioscience, biotechnology, and biochemistry》2007,71(11):2751-2758
New clerodane-type diterpenes, designated as parvitexins A (1)-E (5), were isolated from the in vitro-cultured liverwort, Scapania parvitexta. These compounds were determined to be monoacetylated clerodane-type diterpenes based on spectroscopic evidence. 相似文献
958.
Sugimoto S Fujii T Morimiya T Johdo O Nakamura T 《Bioscience, biotechnology, and biochemistry》2007,71(9):2184-2189
Tempeh is a traditional Indonesian soybean-fermented food produced by filamentous fungi, Rhizopus sp. and Fusarium sp. We isolated and sequenced the genomic gene and a cDNA clone encoding a novel protease (FP) from Fusarium sp. BLB. The genomic gene was 856 bp in length and contained two introns. An isolated cDNA clone encoded a protein of 250 amino acids. The predicted amino acid sequence of FP showed highest homology, of 76%, with that of trypsin from Fusarium oxysporum. The hydrolysis activity of FP toward synthetic peptide was higher than that of any other protease tested, including Nattokinases. Furthermore, the thrombolytic activity of FP was about 2.1-fold higher than that of Nattokinase when the concentration of plasminogen was 24 units/ml. These results suggest that FP is superior to Nattokinases in dissolving fibrin when absorbed into the blood. 相似文献
959.
Akiko Takasuga Toshio Watanabe Yasushi Mizoguchi Takashi Hirano Naoya Ihara Atsushi Takano Kou Yokouchi Akira Fujikawa Kazuyoshi Chiba Naohiko Kobayashi Ken Tatsuda Toshiaki Oe Megumi Furukawa-Kuroiwa Atsuko Nishimura-Abe Tatsuo Fujita Kazuya Inoue Kazunori Mizoshita Atsushi Ogino Yoshikazu Sugimoto 《Mammalian genome》2007,18(2):125-136
To map quantitative trait loci (QTL) for growth and carcass traits in a purebred Japanese Black cattle population, we conducted
multiple QTL analyses using 15 paternal half-sib families comprising 7860 offspring. We identified 40 QTL with significant
linkages at false discovery rates of less than 0.1, which included 12 for intramuscular fat deposition called marbling and
12 for cold carcass weight or body weight. The QTL each explained 2%–13% of the phenotypic variance. These QTL included many
replications and shared hypothetical identical-by-descent (IBD) alleles. The QTL for CW on BTA14 was replicated in five families
with significant linkages and in two families with a 1% chromosome-wise significance level. The seven sires shared a 1.1-Mb
superior Q haplotype as a hypothetical IBD allele that corresponds to the critical region previously refined by linkage disequilibrium
mapping. The QTL for marbling on BTA4 was replicated in two families with significant linkages. The QTL for marbling on BTA6,
7, 9, 10, 20, and 21 and the QTL for body weight on BTA6 were replicated with 1% and/or 5% chromosome-wise significance levels.
There were shared IBD Q or q haplotypes in the marbling QTL on BTA4, 6, and 10. The allele substitution effect of these haplotypes ranged from 0.7 to
1.2, and an additive effect between the marbling QTL on BTA6 and 10 was observed in the family examined. The abundant and
replicated QTL information will enhance the opportunities for positional cloning of causative genes for the quantitative traits
and efficient breeding using marker-assisted selection.
Electronic Supplementary Material Electronic Supplementary material is available for this article at
and accessible for authorised users. 相似文献
960.
Oi-Kano Y Kawada T Watanabe T Koyama F Watanabe K Senbongi R Iwai K 《The Journal of nutritional biochemistry》2007,18(10):685-692
The effects of extra virgin olive oil (EV-olive oil) on triglyceride metabolism were investigated by measuring the degree of thermogenesis in interscapular brown adipose tissue (IBAT) and the rates of noradrenaline and adrenaline secretions in rats, both in vivo and in situ. In Experiment 1 (in vivo), rats were given an isoenergetic high-fat diet (30% fat diet) containing corn oil, refined olive oil, or EV-olive oil. After 28 days of feeding, the final body weight, weight gain, energy efficiency, perirenal adipose tissue and epididymal fat pad and plasma triglyceride concentrations were the lowest in the rats fed the EV-olive oil diet. The content of uncoupling protein 1 (UCP1) in IBAT and the rates of urinary noradrenaline and adrenaline excretions were the highest in the rats fed the EV-olive oil diet. In Experiment 2 (in situ), the effects of the extract of the phenolic fraction from EV-olive oil and a compound having excellent characteristics as components of EV-olive oil, hydroxytyrosol, on noradrenaline and adrenaline secretions were evaluated. The intravenous administration of the extract of the phenolic fraction from EV-olive oil significantly increased plasma noradrenaline and adrenaline concentrations, whereas that of hydroxytyrosol had no effect. These results suggest that phenols except hydroxytyrosol in EV-olive oil enhance thermogenesis by increasing the UCP1 content in IBAT and enhancing noradrenaline and adrenaline secretions in rats. 相似文献