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排序方式: 共有955条查询结果,搜索用时 224 毫秒
241.
Kiyoshi Tajima Hideyuki Ohmori Rustam I. Aminov Yuri Kobashi Tomoyuki Kawashima 《Anaerobe》2010,16(1):6-11
Because of limitations imposed on the antibiotic use in animal industry, there is a need for alternatives to maintain the efficiency of production. One of them may be the use of fermented liquid feed (FLF) but how it affects gut ecology is poorly understood. We investigated the effect of three diets, standard dry feed (control), dry feed supplemented with antibiotics, and fermented liquid feed (FLF, fermented with Lactobacillus plantarum), on gut bacterial diversity in piglets. The structure of the ileal and caecal communities was estimated by sequencing the SSU rRNA gene libraries. Antibiotic-supplemented feed slightly increased bacterial diversity in the ileum but reduced it in the caecum while in FLF-fed animals bacterial diversity was elevated. The majority of bacterial sequences in the ileum of all three groups belonged to lactobacilli (92–98%). In the caecum the lactobacilli were still dominant in control and antibiotic-fed animals (59% and 64% of total bacterial sequences, respectively) but in FLF-fed animals they fell to 31% with the concomitant increase in the Firmicutes diversity represented by the Dorea, Coprococcus, Roseburia and Faecalibacterium genera. Thus FLF affects the gut ecology in a different way than antibiotics and contributes to the enhanced bacterial diversity in the gastrointestinal tract. 相似文献
242.
Yoshizawa AC Kawashima S Okuda S Fujita M Itoh M Moriya Y Hattori M Kanehisa M 《Traffic (Copenhagen, Denmark)》2006,7(8):1104-1118
The SNARE proteins are required for membrane fusion during intracellular vesicular transport and for its specificity. Only the unique combination of SNARE proteins (cognates) can be bound and can lead to membrane fusion, although the characteristics of the possible specificity of the binding combinations encoded in the SNARE sequences have not yet been determined. We discovered by whole genome sequence analysis that sequence motifs (conserved sequences) in the SNARE motif domains for each protein group correspond to localization sites or transport pathways. We claim that these motifs reflect the specificity of the binding combinations of SNARE motif domains. Using these motifs, we could classify SNARE proteins from 48 organisms into their localization sites or transport pathways. The classification result shows that more than 10 SNARE subgroups are kingdom specific and that the SNARE paralogs involved in the plasma membrane-related transport pathways have developed greater variations in higher animals and higher plants than those involved in the endoplasmic reticulum-related transport pathways throughout eukaryotic evolution. 相似文献
243.
Takasugi K Yamamura M Iwahashi M Otsuka F Yamana J Sunahori K Kawashima M Yamada M Makino H 《Arthritis research & therapy》2006,8(4):R126-13
Despite its potent ability to inhibit proinflammatory cytokine synthesis, interleukin (IL)-10 has a marginal clinical effect
in rheumatoid arthritis (RA) patients. Recent evidence suggests that IL-10 induces monocyte/macrophage maturation in cooperation
with macrophage-colony stimulating factor (M-CSF). In the present study, we found that the inducible subunit of the IL-10
receptor (IL-10R), type 1 IL-10R (IL-10R1), was expressed at higher levels on monocytes in RA than in healthy controls, in
association with disease activity, while their expression of both type 1 and 2 tumour necrosis factor receptors (TNFR1/2)
was not increased. The expression of IL-10R1 but not IL-10R2 was augmented on monocytes cultured in the presence of RA synovial
tissue (ST) cell culture supernatants. Cell surface expression of TNFR1/2 expression on monocytes was induced by IL-10, and
more efficiently in combination with M-CSF. Two-color immunofluorescence labeling of RA ST samples showed an intensive coexpression
of IL-10R1, TNFR1/2, and M-CSF receptor in CD68+ lining macrophages. Adhered monocytes, after 3-day preincubation with IL-10 and M-CSF, could produce more IL-1β and IL-6
in response to TNF-α in the presence of dibutyryl cAMP, as compared with the cells preincubated with or without IL-10 or M-CSF
alone. Microarray analysis of gene expression revealed that IL-10 activated various genes essential for macrophage functions,
including other members of the TNFR superfamily, receptors for chemokines and growth factors, Toll-like receptors, and TNFR-associated
signaling molecules. These results suggest that IL-10 may contribute to the inflammatory process by facilitating monocyte
differentiation into TNF-α-responsive macrophages in the presence of M-CSF in RA. 相似文献
244.
245.
Saga H Kimura K Hayashi K Gotow T Uchiyama Y Momiyama T Tadokoro S Kawashima N Jimbou A Sobue K 《Experimental cell research》1999,247(1):279-292
Alpha-Smooth muscle actin is one of the molecular markers for a phenotype of vascular smooth muscle cells, because the actin is a major isoform expressed in vascular smooth muscle cells and its expression is upregulated during differentiation. Here, we first demonstrate that the phenotype-dependent expression of this actin in visceral smooth muscles is quite opposite to that in vascular smooth muscles. This actin isoform is not expressed in adult chicken visceral smooth muscles including gizzard, trachea, and intestine except for the inner layer of intestinal muscle layers, whereas its expression is clearly detected in these visceral smooth muscles at early stages of the embryo (10-day-old embryo) and is developmentally downregulated. In cultured gizzard smooth muscle cells maintaining a differentiated phenotype, alpha-smooth muscle actin is not detected while its expression dramatically increases during serum-induced dedifferentiation. Promoter analysis reveals that a sequence (-238 to -219) in the promoter region of this actin gene acts as a novel negative cis-element. In conclusion, the phenotype-dependent expression of alpha-smooth muscle actin would be regulated by the sum of the cooperative contributions of the negative element and well-characterized positive elements, purine-rich motif, and CArG boxes and their respective transacting factors. 相似文献
246.
Takii T Hayashi M Hiroma H Chiba T Kawashima S Zhang HL Nagatsu A Sakakibara J Onozaki K 《Journal of biochemistry》1999,125(5):910-915
N-(p-Coumaroyl)serotonin (CS) with antioxidative activity is present in safflower oil. We have reported that CS inhibits proinflammatory cytokine generation from human monocytes in vitro. As reactive oxygen species (ROS) affect cell proliferation, in this study the effect of CS on the proliferation of various cell types was examined. CS augments the proliferation of normal human and mouse fibroblast cells. The cells continue to proliferate in the presence of CS and form a transformed cell-like focus without transformation. CS, however, does not augment the proliferation of other cell types, either normal or tumor cells. CS augments the proliferation of fibroblasts in synergy with basic fibroblast growth factor (bFGF) or epidermal growth factor (EGF), but not with acidic FGF(aFGF) or platelet-derived growth factor (PDGF). This study using synthesized derivatives of CS reveals that the growth-promoting activity is not due to antioxidative activity. These findings indicate that CS is a natural compound with unique growth-promoting activity for fibroblasts. 相似文献
247.
Kasashima S Kawashima A Muroishi Y Futakuchi H Nakanishi I Oda Y 《Histochemistry and cell biology》1999,111(3):197-207
We examined the cerebral cortex of five autopsied individuals without neurological and psychiatric diseases by immunohistochemistry
using an anti-human recombinant choline acetyltransferase (ChAT) polyclonal antibody and in situ hybridization with 35S-labeled human ChAT riboprobes. The immunohistochemistry detected positive neurons which were medium-sized or large pyramidal
neurons located predominantly in layers III and V. The density of such neurons was higher in the motor and secondary sensory
areas than in other cortical areas; the immunoreactive neurons in layer V were more densely distributed in the motor area
and those in layer III were distributed in the secondary sensory areas. Positively stained, non-pyramidal neurons were observed
in the superficial layer of the cingulate gyrus and parahippocampus. No immunoreactive neurons were found in the primary sensory
areas. The in situ hybridization detected some neurons with signals for ChAT mRNA in the cerebral cortex, most of which were
distributed in layer V of the motor area and in layer III of the secondary visual area. These results indicate that the human
cerebral cortex contains cholinergic neurons and displays regional and laminal variations in their distribution.
Accepted: 17 November 1998 相似文献
248.
An anti-proliferative gene BTG1 regulates angiogenesis in vitro 总被引:5,自引:0,他引:5
Iwai K Hirata K Ishida T Takeuchi S Hirase T Rikitake Y Kojima Y Inoue N Kawashima S Yokoyama M 《Biochemical and biophysical research communications》2004,316(3):628-635
B-cell translocation gene 1 (BTG1) is a member of the anti-proliferative gene family that regulates cell growth and differentiation. To clarify the role of BTG1 in angiogenesis, we examined the regulation of BTG1 expression in cultured endothelial cells and characterized its function in in vitro models of angiogenesis. BTG1 mRNA was abundantly expressed in quiescent endothelial cells. Addition of serum and angiogenic growth factors decreased BTG1 mRNA levels in endothelial cells. In contrast, BTG1 mRNA was up-regulated in tube-forming endothelial cells on Matrigel. This up-regulation was partially blocked by neutralizing antibody against transforming growth factor-beta (TGF-beta), and TGF-beta increased BTG1 mRNA levels. Inhibition of endogenous BTG1 by overexpression of antisense BTG1 resulted in inhibited network formation, and overexpression of sense BTG1 augmented tube formation in these cell lines. BTG1-overexpressing endothelial cells displayed increased cell migration. These findings suggest that BTG1 may play an important role in the process of angiogenesis. 相似文献
249.
Kojma Y Hirata K Ishida T Shimokawa Y Inoue N Kawashima S Quertermous T Yokoyama M 《The Journal of biological chemistry》2004,279(52):54032-54038
Endothelial lipase (EL), a new member of the lipoprotein lipase gene family, plays a central role in high density lipoprotein metabolism. Previous studies indicated that EL is expressed in endothelial cells, macrophages, and smooth muscle cells in atherosclerotic lesions in human coronary arteries. However, the functional role of EL in the local vessel wall remains obscure. In this study, we evaluated the ability of EL to modulate monocyte adhesion to the endothelial cell surface. EL mRNA and protein levels were markedly increased in tissues of the mouse model of inflammation induced by lipopolysaccharide injection. Adhesion assays in vitro revealed that overexpression of EL in COS7 or Pro5 cells enhanced monocyte bindings to the EL-expression cells. Heparin or heparinase treatment inhibited EL-mediated increases of monocyte adhesion in a dose-dependent manner. Moreover, ex vivo adhesion assays revealed that the number of adherent monocytes on aortic strips was significantly increased in EL transgenic mice and decreased in EL knock-out mice as compared with wild-type mice. These results suggest that EL on the endothelial cell surface can promote monocyte adhesion to the vascular endothelium through the interaction with heparan sulfate proteoglycans. Thus, the up-regulation of EL by inflammatory stimuli may be involved in the progression of inflammation. 相似文献
250.
Kawashima H Watanabe N Hirose M Sun X Atarashi K Kimura T Shikata K Matsuda M Ogawa D Heljasvaara R Rehn M Pihlajaniemi T Miyasaka M 《The Journal of biological chemistry》2003,278(15):13069-13076
Leukocyte infiltration during inflammation is mediated by the sequential actions of adhesion molecules and chemokines. By using a rat ureteral obstruction model, we showed previously that L-selectin plays an important role in leukocyte infiltration into the kidney. Here we report the purification, identification, and characterization of an L-selectin-binding heparan sulfate proteoglycan (HSPG) expressed in the rat kidney. Partial amino acid sequencing and Western blotting analyses showed that the L-selectin-binding HSPG is collagen XVIII, a basement membrane HSPG. The binding of L-selectin to isolated collagen XVIII was specifically inhibited by an anti-L-selectin monoclonal antibody, EDTA, treatment of the collagen XVIII with heparitinase or heparin but not by chemically desulfated heparin. A cell binding assay showed that the L-selectin-collagen XVIII interaction mediates cell adhesion. Interestingly, collagen XVIII also interacted with a chemokine, monocyte chemoattractant protein-1, and presented it to a monocytic cell line, THP-1, which enhanced the alpha(4)beta(1) integrin-mediated binding of the THP-1 cells to vascular cell adhesion molecule-1. Thus, collagen XVIII may provide a link between selectin-mediated cell adhesion and chemokine-induced cellular activation and accelerate the progression of leukocyte infiltration in renal inflammation. 相似文献