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71.
When activated by viral infection, plasmacytoid dendritic cells (pDCs) play a primary role in the immune response through secretion of IFN-α. Lactococcus lactis subsp. lactis JCM5805 (JCM5805) is a strain of lactic acid bacteria (LAB) that activates murine and human pDCs to express type I and type III interferons (IFNs). JCM5805 has also been shown to activate pDCs via a Toll-like receptor 9 (TLR9) dependent pathway. In this study, we investigated the anti-viral effects of oral administration of JCM5805 using a mouse model of murine parainfluenza virus (mPIV1) infection. JCM5805-fed mice showed a drastic improvement in survival rate, prevention of weight loss, and reduction in lung histopathology scores compared to control mice. We further examined the mechanism of anti-viral effects elicited by JCM5805 administration using naive mice. Microscopic observations showed that JCM5805 was incorporated into CD11c+ immune cells in Peyer’s patches (PP) and PP pDCs were significantly activated and the expression levels of IFNs were significantly increased. Interestingly, nevertheless resident pDCs at lung were not activated and expressions levels of IFNs at whole lung tissue were not influenced, the expressions of anti-viral factors induced by IFNs, such as Isg15, Oasl2, and Viperin, at lung were up-regulated in JCM5805-fed mice compared to control mice. Therefore expressed IFNs from intestine might be delivered to lung and IFN stimulated genes might be induced. Furthermore, elevated expressions of type I IFNs from lung lymphocytes were observed in response to mPIV1 ex vivo stimulation in JCM5805-fed mice compared to control. This might be due to increased ratio of pDCs located in lung were significantly increased in JCM5805 group. Taken together, a specific LAB strain might be able to affect anti-viral immunological profile in lung via activation of intestinal pDC leading to enhanced anti-viral phenotype in vivo. 相似文献
72.
Tetsu Yamane Masako Mitsumata Noriko Yamaguchi Tadao Nakazawa Kunio Mochizuki Tetsuo Kondo Tomonori Kawasaki Shin-ichi Murata Yoji Yoshida Ryohei Katoh 《Cell and tissue research》2010,340(3):471-479
Remodeling of endothelial basement membrane is important in atherogenesis. Since little is known about the actual relationship
between type IV collagen and matrix metalloprotease−2 (MMP-2) in endothelial cells (ECs) under shear stress by blood flow,
we performed quantitative analysis for type IV collagen and MMP-2 in ECs under high shear stress. The mRNA of type IV collagen
from ECs exposed to high shear stress (10 and 30 dyn/cm2) had a higher expression compared to ECs exposed to a static condition or low shear stress (3 dyn/cm2) (P < 0.01). 3H-proline uptake analysis and fluorography revealed a remarkable increase of type IV collagen under high shear stress (P < 0.01). In contrast, zymography revealed that exposing to high shear stress, however similar positivity was leveled in the
intracellular MMP-2 in the control and high shear stress-exposed ECs, reduced the secretion of MMP-2 in ECs. The results of
Northern blotting, gelatin zymography and monitoring the intracellular trafficking of GFP-labeled MMP-2 revealed that MMP-2
secretion by ECs was completely suppressed by high shear stress, but the intracellular mRNA expression, protein synthesis,
and transport of MMP-2 were not affected. In conclusion, we suggest that high shear stress up-regulates type IV collagen synthesis
and down-regulates MMP-2 secretion in ECs, which plays an important role in remodeling of the endothelial basement membrane
and may suppress atherogenesis. 相似文献
73.
Kobayashi T Liu X Wen FQ Fang Q Abe S Wang XQ Hashimoto M Shen L Kawasaki S Kim HJ Kohyama T Rennard SI 《Biochemical and biophysical research communications》2005,327(2):393-398
Transforming growth factor-beta1 (TGF-beta1) is a key factor in a variety of physiological and pathological processes. Vascular endothelial growth factor (VEGF) is a key angiogenic factor, and vascular change is one of the features of airway remodeling. We examined the effect of TGF-beta1 on VEGF production by fibroblasts from mice lacking expression of Smad2 or Smad3 as well as human lung fibroblasts treated with or without Smad2 or Smad3 siRNA. TGF-beta1 stimulated VEGF production by fibroblasts from Smad2 deficient animals and wildtype animals. In contrast, TGF-beta1 did not affect VEGF production by fibroblasts from Samd3 deficient mice. Similarly, TGF-beta1 failed to stimulate VEGF production by HFL-1 cells treated with Samd3 siRNA but significantly increased VEGF production by the cells treated with Smad2 siRNA. These result suggest that TGF-beta1 stimulation of VEGF production by fibroblasts is regulated by Smad3 but not by Smad2 signaling. 相似文献
74.
Distribution of dissolved organic carbon and dissolved fulvic acid in mesotrophic Lake Biwa, Japan 总被引:1,自引:0,他引:1
The dissolved organic carbon (DOC) concentrations in mesotrophic Lake Biwa were determined by a total organic carbon (TOC)
analyzer, and DOC molecular size distributions were determined by size exclusion chromatography (SEC) using a fluorescence
detector at excitation/emission (Ex/Em) levels of 300/425 nm with the eluent at pH 9.7. The fluorescence wavelengths for detection
were chosen from the result of excitation–emission matrix spectrometry (EEM) analysis for dissolved fulvic acid (DFA) extracted
from Ado River (peak A, Ex/Em = 260–270/430–440 nm; peak B, Ex/Em = 300–310/420–430 nm). Ado River DFA was eluted with a retention
time (RT) of 7.4–8.9 min and the apparent molecular weight was estimated at 22–87 kDa based on the elution curve for the spherical
protein molecular weight standard. A DFA peak eluted at the same retention time as Ado River DFA also appeared in all the
samples of Lake Biwa water. From the linear relationship between the peak areas with an RT of 7.4–8.9 min by SEC analysis
and DOC values of DFA by TOC analysis of a series of DFA samples (r2 = 0.9995), the concentrations of DFA in the lake water were roughly calculated. DFA was distributed within the range 0.25–0.43 mg C l−1 and accounted for 15%–41% of DOC, with the highest ratios observed at a depth of 70 m in August and the lowest at 2.5 m in
May. 相似文献
75.
Identification of the sex pheromone components secreted by female moths of Peridroma saucia (Noctuidae: Noctuinae) 总被引:1,自引:0,他引:1
Inomata S Tsuchiya S Ikeda K Saito O Ando T 《Bioscience, biotechnology, and biochemistry》2002,66(11):2461-2464
The variegated cutworm, Peridroma saucia Hübner, is a lepidopteran pest to a large number of crops in Canada, the United States, and Europe. It was probably naturalized in Japan in the 1970s. The pheromone glands of the female moth include two components with electroantennographic activity in a ratio of 3:1. GC-MS analyses of pheromone extracts untreated and treated with dimethyl disulfide revealed the major component to be (Z)-11-hexadecenyl acetate and the minor component to be (Z)-9-tetradecenyl acetate. The synthetic pheromone was used to attract a large number of males in a vegetable field in Tokyo, which suggests that this species has already become a harmful pest in Japan. 相似文献
76.
Xiangde Liu Shinsaku Togo Mona Al-Mugotir Huijung Kim QiuHong Fang Tetsu Kobayashi XingQi Wang Lijun Mao Peter Bitterman Stephen Rennard 《Respiratory research》2008,9(1):66
Background
We have previously reported that low concentrations of cigarette smoke extract induce DNA damage without leading to apoptosis or necrosis in human bronchial epithelial cells (HBECs), and that IL-6/STAT3 signaling contributes to the cell survival. Since NF-κB is also involved in regulating apoptosis and cell survival, the current study was designed to investigate the role of NF-κB in mediating cell survival in response to cigarette smoke exposure in HBECs.Methods
Both the pharmacologic inhibitor of NF-κB, curcumin, and RNA interference targeting p65 were used to block NF-κB signaling in HBECs. Apoptosis and cell survival were then assessed by various methods including COMET assay, LIVE/DEAD Cytotoxicity/Viability assay and colony formation assay.Results
Cigarette smoke extract (CSE) caused DNA damage and cell cycle arrest in S phase without leading to apoptosis in HBECs as evidenced by TUNEL assay, COMET assay and DNA content assay. CSE stimulated NF-κB -DNA binding activity and up-regulated Bcl-XL protein in HBECs. Inhibition of NF-κB by the pharmacologic inhibitor curcumin (20 μM) or suppression of p65 by siRNA resulted in a significant increase in cell death in response to cigarette smoke exposure. Furthermore, cells lacking p65 were incapable of forming cellular colonies when these cells were exposed to CSE, while they behaved normally in the regular culture medium.Conclusion
The current study demonstrates that CSE activates NF-κB and up-regulates Bcl-XL through NF-kB activation in HBECs, and that CSE induces cell death in cells lacking p65. These results suggest that activation of NF-κB regulates cell survival following DNA damage by cigarette smoke in human bronchial epithelial cells. 相似文献77.
78.
Tetsu Hirata 《Ecological Research》1992,7(1):31-42
Successional changes of sessile organisms over about 3 years on concrete plates immersed at depths of 1.0, 2.5, 4.0 and 5.5
m in Nabeta Bay, Shimoda, Pacific coast of Japan, were investigated from their species composition, percentage cover, and
the structure, metabolism, biomass and maturity of the community for the purpose of verifying the hypothesis of succession
by Margalef (1968) and Odum (1969). The process of succession was divided into five stages from a cluster analysis based on
Horn's (1966) similarity in community structure. The five stages were characterized from dominant, species and 18 community
attributes in terms of structure, metabolism, biomass and maturity. With the advance of stages, two large-sized, long-lived
species, the kelpEisenia bicyclis and the oysterCrassostrea nippona, dominated; 18 community attributes showed a directional succession ending in a constant community structure, low community
metabolism, accumulation of community biomass except chlorophylla and an enhanced degree of community maturity. This directionality in succession of community attributes was valid for the
prediction of Margalef and Odum, despite a tendency for estimated daily energy budget to be more heterotrophic in such an
open system. From these results, it was suggested that the definition of succession by Odum (1969) should be interpreted as
the regularity in shift of dominant species, not individual species, and as the control of system by feedback mechanism developing
with succession rather than community-controlled mechanism. 相似文献
79.
Takatoshi Soga Takahide Ohishi Tetsuo Matsui Tetsu Saito Mitsuyuki Matsumoto Jun Takasaki Shun-ichiro Matsumoto Masazumi Kamohara Hideki Hiyama Shigeru Yoshida Kazuhiro Momose Yoshitaka Ueda Hitoshi Matsushime Masato Kobori Kiyoshi Furuichi 《Biochemical and biophysical research communications》2005,329(1):417
80.
Atsushi Tero Kenji Yumiki Ryo Kobayashi Tetsu Saigusa Toshiyuki Nakagaki 《Theorie in den Biowissenschaften》2008,127(2):89-94
Understanding how biological systems solve problems could aid the design of novel computational methods. Information processing
in unicellular eukaryotes is of particular interest, as these organisms have survived for more than a billion years using
a simple system. The large amoeboid plasmodium of Physarum is able to solve a maze and to connect multiple food locations via a smart network. This study examined how Physarum amoebae compute these solutions. The mechanism involves the adaptation of the tubular body, which appears to be similar to
a network, based on cell dynamics. Our model describes how the network of tubes expands and contracts depending on the flux
of protoplasmic streaming, and reproduces experimental observations of the behavior of the organism. The proposed algorithm
based on Physarum is simple and powerful. 相似文献