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41.
Visual and olfactory cues for mate orientation behaviour in male white-spotted longicorn beetle, Anoplophora malasiaca 总被引:1,自引:0,他引:1
Midori Fukaya Toshiharu Akino Tetsuya Yasuda Hiroe Yasui & Sadao Wakamura 《Entomologia Experimentalis et Applicata》2004,111(2):111-115
Olfactory and visual cues were shown to mediate short‐distance orientation in Anoplophora malasiaca (Thomson) (Coleoptera: Cerambycidae). In a laboratory test, more than 80% (n = 42) of males walked straight upward when presented with an untreated surface with a 75° slope. When a freshly killed female was fixed at a short distance (10 cm ahead and 5 cm to left/right) from the starting point, 50% of males (n = 30) were oriented toward the female before direct contact. Similar behavioural responses were observed when female extract was directly applied to the slope or to a glass rod model fixed on the slope. When black, white, and transparent coloured rods with the extract were presented, the orientation response was significantly greater for black than to white and transparent rods, to which only a negligible response was observed. 相似文献
42.
Seiji Murakami Daisuke Iwaki Hiroaki Mitsuzawa Hitomi Sano Hiroki Takahashi Dennis R Voelker Toyoaki Akino Yoshio Kuroki 《The Journal of biological chemistry》2002,277(9):6830-6837
Pulmonary surfactant protein A (SP-A) plays an important role in modulation of the innate immune system of the lung. Peptidoglycan (PGN), a cell wall component of Gram-positive bacteria, is known to elicit excessive proinflammatory cytokine production from immune cells. In this study we investigated whether SP-A interacts with PGN and alters PGN-elicited cellular responses. Binding studies demonstrate that PGN is not a ligand for SP-A. However, SP-A significantly reduced PGN-elicited tumor necrosis factor alpha (TNF-alpha) secretion by U937 cells and rat alveolar macrophages. The inhibitory effect on TNF-alpha secretion was dependent upon SP-A concentrations in physiological range. Coincubation of SP-A and PGN with human embryonic kidney 293 cells that had been transiently transfected with the cDNA of Toll-like receptor 2 (TLR2), a cell signaling receptor for PGN, significantly attenuated PGN-induced nuclear factor-kappaB activity. SP-A directly bound to a soluble form of the recombinant extracellular TLR2 domain (sTLR2). Coincubation of sTLR2 with SP-A significantly reduced the binding of sTLR2 to PGN. These results indicate that the direct interaction of SP-A with TLR2 alters PGN-induced cell signaling. We propose that SP-A modulates inflammatory responses against the bacterial components by interactions with pattern-recognition receptors. 相似文献
43.
Akio Shimizu Hironao Nakayama Priscilla Wang Courtney K?nig Tomoshige Akino Johanna Sandlund Silvia Coma Joseph E. Italiano Jr. Akiko Mammoto Diane R. Bielenberg Michael Klagsbrun 《The Journal of biological chemistry》2013,288(4):2210-2222
Glioblastomas are very difficult tumors to treat because they are highly invasive and disseminate within the normal brain, resulting in newly growing tumors. We have identified netrin-1 as a molecule that promotes glioblastoma invasiveness. As evidence, netrin-1 stimulates glioblastoma cell invasion directly through Matrigel-coated transwells, promotes tumor cell sprouting and enhances metastasis to lymph nodes in vivo. Furthermore, netrin-1 regulates angiogenesis as shown in specific angiogenesis assays such as enhanced capillary endothelial cells (EC) sprouting and by increased EC infiltration into Matrigel plugs in vivo, as does VEGF-A. This netrin-1 signaling pathway in glioblastoma cells includes activation of RhoA and cyclic AMP response element-binding protein (CREB). A novel finding is that netrin-1-induced glioblastoma invasiveness and angiogenesis are mediated by activated cathepsin B (CatB), a cysteine protease that translocates to the cell surface as an active enzyme and co-localizes with cell surface annexin A2 (ANXA2). The specific CatB inhibitor CA-074Me inhibits netrin-1-induced cell invasion, sprouting, and Matrigel plug angiogenesis. Silencing of CREB suppresses netrin-1-induced glioblastoma cell invasion, sprouting, and CatB expression. It is concluded that netrin-1 plays an important dual role in glioblastoma progression by promoting both glioblastoma cell invasiveness and angiogenesis in a RhoA-, CREB-, and CatB-dependent manner. Targeting netrin-1 pathways may be a promising strategy for brain cancer therapy. 相似文献
44.
Suzuki J Kato A Maeda N Hashimoto C Uchikoshi M Mizutani T Doke C Matsuzawa T 《Primates; journal of primatology》2003,44(3):273-280
We examined growth changes in concentrations of plasma insulin-like growth factor-1 (IGF-1) and testosterone, and somatometric
parameters in two captive male agile gibbons from birth to about 4 years of age, to examine the evolution of growth patterns
in primates. Plasma IGF-1 concentrations in agile gibbons generally increased with age with values ranging from 200 to 1,100 ng/ml.
The growth profiles in plasma IGF-1 in the gibbons were similar to those reported for chimpanzees. The highest concentrations
of plasma testosterone (230 and 296 ng/dl) were observed within the first 0.3 years from birth, then the concentrations rapidly
decreased and fluctuated below 100 ng/dl. Continuously higher IGF-1 concentrations were observed after 2.6 and 3.5 years of
age. The profiles of plasma testosterone in these gibbons also resembled those of other primates including humans. However,
their plasma testosterone levels in both neonate and adult stages (60 ng/dl) were lower than those reported for macaques and
chimpanzees of respective stages. The obtained growth profiles of plasma IGF-1 and testosterone suggest that the adolescent
phase starts around 2.6 or 3.5 years of age in male agile gibbons. The growth trend in many morphological parameters including
body weight showed a linear increase without a significant growth spurt at approximately the onset of puberty. Head length
and first digit length had reached a plateau during the study period. Brachial index, which indicates the relative length
of forearm to upper arm, significantly increased gradually through the growth period. This result indicates that forearm becomes
relatively longer than the upper arm with growth, which may be an evolutionary adaptation for brachiation. 相似文献
45.
46.
Munetoshi Maruyama Florian M Steiner Christian Stauffer Toshiharu Akino Ross H Crozier Birgit C Schlick-Steiner 《BMC evolutionary biology》2008,8(1):237
Background
Ants of the genus Lasius are ecologically important and an important system for evolutionary research. Progress in evolutionary research has been hindered by the lack of a well-founded phylogeny of the subgenera, with three previous attempts disagreeing. Here we employed two mitochondrial genes (cytochrome c oxidase subunit I, 16S ribosomal RNA), comprising 1,265 bp, together with 64 morphological characters, to recover the phylogeny of Lasius by Bayesian and Maximum Parsimony inference after exploration of potential causes of phylogenetic distortion. We use the resulting framework to infer evolutionary pathways for social parasitism and fungiculture. 相似文献47.
48.
Kohei Matsuda Noritaka Ohga Yasuhiro Hida Kunihiko Tsuchiya Takuro Kurosu Tomoshige Akino Shou-Ching Shih Michael Klagsbrun Kyoko Hida 《Biochemical and biophysical research communications》2010,394(4):947-70
Tumor angiogenesis is necessary for solid tumor progression and metastasis. Increasing evidence indicates that tumor endothelial cells (TECs) are more relevant to the study of tumor angiogenesis than normal endothelial cells (NECs) because their morphologies and gene expression are different from NECs. However, it is challenging to isolate and culture large numbers of pure ECs from tumor tissue since the percentage of ECs is only about 1-2% and tumor cells and fibroblasts easily overgrow them. In addition, there has been concern that isolated TECs may lose their special phenotype once they are dissociated from tumor cells.In this study, we have successfully purified murine TECs from four different human tumor xenografts and NECs from murine dermal tissue. Isolated ECs expressed endothelial markers, such as CD31, VE-cadherin (CD144), and endoglin (CD105), for more than 3 months after isolation. TECs maintained tumor endothelial-specific markers, such as tumor endothelial marker 8 (TEM8) and aminopeptidase N (APN), as in tumor blood vessels in vivo. In addition, TECs were more proliferative and motile than NECs. TECs showed a higher response to VEGF and higher expression of VEGF receptors-1 and -2 than NECs did. Stem cell antigen-1 was up-regulated in all four TECs, suggesting that they have a kind of stemness. Cultured TECs maintain distinct biological differences from NECs as in vivo. In conclusion, it was suggested that TECs are relevant material for tumor angiogenesis research. 相似文献
49.
Handa T Hirose A Akino T Watanabe K Tsuchiya H 《Biotechnology and bioengineering》1983,25(12):2957-2967
In this report, alpha-Amylase originating from Bacillus subtilis (liquefying type) was immobilized on partially imidoesterized polyacrylonitrile (PAN) by covalent bonding. For the preparation of immobilized alpha-amylase, which has a high activity and high stability to repeated use, the optimum conditions for the preparation reaction were investigated. The optimum conditions for the preparation reaction were quantified on the basis of the enzymatic activity, the preservation of the activity during repeated use in batch process and the protein content on the support. Further-more, enzymatic properties of immobilized alpha-amylase prepared at optimum conditions were compared with the native enzyme. The optimum temperature and reaction time for the imidoes-terification reaction were 30 degrees c and 6 h, respectively, whereas those of the amidinatin reaction were 30-40 degrees C and more than 3 h, respectively; the optimum pH range was 9-10. Immobilized alpha-amylase prepared at the optimum conditions was very stable against the repeated use and had more than 90% of relative to activity of the first use after the tenth procedure. The initial reaction rate of immobilized alpha-amylase was lower than native alpha-amylase, but same amount of reducing sugars were produced after the reaction passed for more than 90 min. The immobilized alpha-amylase was less stabel at the high temperature and the more basic media. However, after long incubation time, immobilized alpha-amylase was more stable than the native enzyme in exposure to heat and a storng base. 相似文献
50.
The catalytic properties of a new type of dihydropteridine reductase, NADPH-specific dihydropteridine reductase [EC 1.6.99.10], from bovine liver, were studied and compared with those of the previously characterized enzyme, NADH-specific dihydropteridine reductase [EC 1.6.99.7]. With quinonoid-dihydro-6-methylpterin, approximate Km values of NADPH-specific dihydropteridine reductase for NADPH and NADH were estimated to be 1.4 micron and 2,900 microns, respectively. The Vmax values were 1.34 mumol/min/mg with NADPH and 1.02 mumol/min/mg with NADPH. With NADPH, the Km values of the enzyme for the quinonoid-dihydro forms of 6-methylpterin and biopterin were 1.4 micron and 6.8 microns, respectively. The enzyme was inhibited by its reaction product, NADP+, in a competitive manner, and the inhibition constant was determined to be 3.2 microns. The enzyme was severely inhibited by L-thyroxine and by 2,6-dichlorophenolindophenol. 相似文献