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Luo  Xinjuan  Zhang  Yanyu  Wu  Hongdou  Bai  Juan 《Protoplasma》2020,257(4):1211-1220
Protoplasma - Autophagy has been reported to be an adapt function of plant cells under various stresses. In this report, autophagy-related gene expressions and carbohydrate...  相似文献   
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BACKGROUND: Pulmonary adiaspiromycosis is a common disease of many species of wild rodents and occasionally of humans, caused by the inhalation of spores of the fungus Chrysosporium parvum var crescens (Emmonsia crescens). CASE: A 74-year-old female with pulmonary adiaspiromycosis was diagnosed by radiologically guided lung fine needle aspiration (FNA). The specimen showed intracellular and extracellular 100-300 microm conidia with a distinct thick, trilaminar wall, which was positive for Gomori-methenamine silver and periodic acid-Schiff stain. The background consisted of a granulomatous process. CONCLUSION: FNA is an effective method of diagnosing pulmonary adiaspiromycosis, and pathologists need to be aware of the characteristic features of this unusual opportunistic fungal infection.  相似文献   
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Phytochemistry Reviews - The production of safe foods with little or no artificial preservatives is one of the foremost leading challenges for food manufacturing industries because synthetic...  相似文献   
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The study aimed to identify the changes of anatomic and microscopic structure and the expression and localization of hypoxia-inducible factor (HIF)-1α and vascular endothelial growth factor (VEGF) in the myocardium and coronary artery of the yak heart adapted to chronic hypoxia with aging. Thirty-two yaks (1 day, 6 months, 1 year, 2 years, and 5 year old) were included, and immunoelectronmicroscopy, immunohistochemistry, and enzyme-linked immunosorbent assay (ELISA) were used. Right ventricular hypertrophy was not present in yaks with aging. There was no intima thickening phenomenon in the coronary artery. The ultrastructure of myofibrils, mitochondria, and collagen fibers and the diameter and quantity of collagen changed significantly with aging. The enzymatic activity of complexes I, II, and V increased with age. Immunogold labeling showed the localization of HIF-1α protein in the cytoplasm and nuclei of endothelial cells and cytoplasm of cardiac muscle cells, and VEGF protein in the nuclei and perinuclei areas of smooth muscle cells of coronary artery, and in the cytoplasm and nuclei of endothelial cells. ELISA results showed that HIF-1α secretion significantly increased in the myocardium and coronary artery from an age of 1 day to 2 years of yaks and decreased in old yaks. However, VEGF protein always increased with aging. The findings of this study suggest that 6 months is a key age of yak before which there are some adaptive changes to deal with low-oxygen environment, and there is a maturation of the yak heart from the age of 6 months to 2 years.  相似文献   
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Bao Y  Zhou Q  Guan L 《Bioresource technology》2008,99(18):8759-8764
Allantoin is one of important nitrogenous compounds in manure. In this study, the simulation experiment of aerobic composting was adopted to explore concentration changes, degradation and relevant influencing factors of allantoin-N during six manure composting. The result showed that the allantoin-N concentration was markedly different among different manures. The various livestock and poultry excreted 1.92-11.14gkg(-1) allantoin-N which accounted for 9.98-32.27% of the total excreted nitrogen. The changing trend of the allantoin-N concentration firstly increased (for 0-14 days), then decreased (for 14-70 days) during different manure composting, and the allantoin-N concentration after composting was lower than the initial allantoin-N concentration in all manure composting. During allantoin degradation for 14-70 days of composting, the half-life of allantoin-N was 57.76 days in broiler manure, 46.21 days in layer-hen manure, 27.73 days in hog manure, 25.67 days in sow manure, 38.51 days in young pig manure and 15.75 days in dairy manure, and the sequence in the half-life was chicken manure>pig manure>dairy manure. Allantoin degradation conformed to first-order kinetics. Through the correlation analysis, hippuric acid, hydrolyzable nitrogen, amino acid-nitrogen, HUN fraction, NO(3)(-)-N and total hydrolyzable nitrogen could be closely related to allantoin-N transforming during composting. Humification could be the main influencing factor for reducing allantoin-N concentration during composting.  相似文献   
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Spores of Bacillus anthracis, the causative agent of anthrax, are known to persist in the host lungs for prolonged periods of time, however the underlying mechanism is poorly understood. In this study, we demonstrated that BclA, a major surface protein of B. anthracis spores, mediated direct binding of complement factor H (CFH) to spores. The surface bound CFH retained its regulatory cofactor activity resulting in C3 degradation and inhibition of downstream complement activation. By comparing results from wild type C57BL/6 mice and complement deficient mice, we further showed that BclA significantly contributed to spore persistence in the mouse lungs and dampened antibody responses to spores in a complement C3-dependent manner. In addition, prior exposure to BclA deletion spores (ΔbclA) provided significant protection against lethal challenges by B. anthracis, whereas the isogenic parent spores did not, indicating that BclA may also impair protective immunity. These results describe for the first time an immune inhibition mechanism of B. anthracis mediated by BclA and CFH that promotes spore persistence in vivo. The findings also suggested an important role of complement in persistent infections and thus have broad implications.  相似文献   
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The opportunistic pathogen Pseudomonas aeruginosa uses the type VI secretion system (T6SS) to deliver the muramidase Tse3 into the periplasm of rival bacteria to degrade their peptidoglycan (PG). Concomitantly, P. aeruginosa uses the periplasm‐localized immunity protein Tsi3 to prevent potential self‐intoxication caused by Tse3, and thus gains an edge over rival bacteria in fierce niche competition. Here, we report the crystal structures of Tse3 and the Tse3–Tsi3 complex. Tse3 contains an annexin repeat‐like fold at the N‐terminus and a G‐type lysozyme fold at the C‐terminus. One loop in the N‐terminal domain (Loop 12) and one helix (α9) from the C‐terminal domain together anchor Tse3 and the Tse3–Tsi3 complex to membrane in a calcium‐dependent manner in vitro, and this membrane‐binding ability is essential for Tse3's activity. In the C‐terminal domain, a Y‐shaped groove present on the surface likely serves as the PG binding site. Two calcium‐binding motifs are also observed in the groove and these are necessary for Tse3 activity. In the Tse3–Tsi3 structure, three loops of Tsi3 insert into the substrate‐binding groove of Tse3, and three calcium ions present at the interface of the complex are indispensable for the formation of the Tse3–Tsi3 complex.  相似文献   
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Shear stress was reported to regulate the expression of AC007362, but its underlying mechanisms remain to be explored. In this study, to isolate endothelial cells of blood vessels, unruptured and ruptured intracranial aneurysm (IA) tissues were collected from IA patients. Subsequently, quantitative real-time PCR (qRT-PCR), Western blot and luciferase assay were performed to investigate the relationships between AC007362, miRNAs-493 and monocyte chemoattractant protein-1 (MCP-1) in human umbilical vein endothelial cells (HUVECs) exposed to shear stress. Reduced representation bisulphite sequencing (RRBS) was performed to assess the level of DNA methylation in AC007362 promoter. Accordingly, AC007362 and MCP-1 were significantly up-regulated while miR-493 was significantly down-regulated in HUVECs exposed to shear stress. AC007362 could suppress the miR-493 expression and elevate the MCP-1 expression, and miR-493 was shown to respectively target AC007362 and MCP-1. Moreover, shear stress in HUVECs led to the down-regulated DNA methyltransferase 1 (DNMT1), as well as the decreased DNA methylation level of AC007362 promoter. Similar results were also observed in ruptured IA tissues when compared with unruptured IA tissues. In conclusion, this study presented a deep insight into the operation of the regulatory network of AC007362, miR-493 and MCP-1 upon shear stress. Under shear stress, the expression of AC007362 was enhanced by the inhibited promoter DNA methylation, while the expression of MCP-1 was enhanced by sponging the expression of miR-493.  相似文献   
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