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The importance of cytokines in disc degeneration is well recognized. Little is known about IL-22 expression in the human intervertebral disc. We investigated IL-22 immuno-localization in disc tissue, and molecular expression and production of IL-22 by annulus cells cultured in three-dimensional (3D) culture. We examined human disc tissue using immunohistochemistry and we cultured isolated annulus cells in 3D to analyze IL-22 expression and production, and its receptor, IL-22R, in conditioned media. Ingenuity pathway analysis (IPA) also was used to identify significant gene expression networks within the molecular data. IL-22 and IL-22R were immunolocalized in many cells in the human outer and inner annulus; fewer cells exhibited localization in the nucleus. Three-dimensional culture of annulus cells demonstrated production of IL-22 in conditioned media; exposure to IL-1ß or TNF-α significantly reduced IL-22 levels. Significant decreases also were identified in conditioned media assayed for IL-22R in TNF-α treated cells. IPA analysis showed that IL-22 ranked among the top canonical pathways. We found constitutive expression and production of IL-22 and IL-22R in the disc, which expands our understanding of the effect of pro-inflammatory cytokines on IL-22 expression and production. Three-dimensional cultured annulus cells exposed to IL-1ß or TNF produced significantly lower levels of IL-22 into their conditioned media compared to levels produced by control cells. Our findings have clinical relevance because of the elevated pro-inflammatory milieu within the degenerating human disc.  相似文献   
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Background  

Most patients who suffer a stroke experience reduced walking competency and health-related quality of life (HRQoL). A key factor in effective stroke rehabilitation is intensive, task-specific training. Recent studies suggest that intensive, patient-tailored training can be organized as a circuit with a series of task-oriented workstations.  相似文献   
35.
Objective: Impaired basal nitric oxide release is associated with a number of cardiovascular disorders including hypertension, arterial spasm, and myocardial infarction. We determined whether basal endothelial nitric oxide release is reduced in otherwise healthy overweight and obese adult humans. Research Methods and Procedures: Seventy sedentary adults were studied: 32 normal weight (BMI <25 kg/m2), 24 overweight (BMI ≥ 25 < 30 kg/m2), and 14 obese (BMI ≥ 30 kg/m2). Forearm blood flow (FBF) responses to intra‐arterial infusions of Ng‐monomethyl‐l ‐arginine (5 mg/min), a nitric oxide synthase inhibitor, were used as an index of basal nitric oxide release. Results: Ng‐monomethyl‐l ‐arginine elicited significant reductions in FBF in the normal weight (from 4.1 ± 0.2 to 2.7 ± 0.2 mL/100 mL tissue/min), overweight (4.1 ± 0.1 to 2.8 ± 0.2 mL/100 mL tissue/min), and obese (3.9 ± 0.3 to 2.7 ± 0.2 mL/100 mL tissue/min) subjects. Importantly, the magnitude of reduction in FBF (~30%) was similar among the groups. Discussion: These results indicate that the capacity of the endothelium to release nitric oxide under basal conditions is not compromised in overweight and obese adults.  相似文献   
36.
Abstract: A decapod crustacean faunule from the lower Miocene (upper Burdigalian, ‘Karpatian’) of the Slovakian part of the Vienna Basin comprise five new species: Callianopsis marianae (Ctenochelidae), Crosniera schweitzerae (Thomassiniidae), Agononida cerovensis and Munidopsis lieskovensis (both Galatheidae) plus Mursia harnicari (Calappidae). The new species of Callianopsis is the first undoubted member of the genus to be recorded from Europe; it is based on sexually dimorphic major and minor chelae as well as on portions of carapace and abdomen. Crosniera schweitzerae sp. nov. and Agononida cerovensis sp. nov. constitute the first fossil members of these genera. Additional material of an enigmatic crab, Styrioplax exiguus, and a re‐examination of the type material, confirms assignment of that genus to the subfamily Rhizopinae (family Pilumnidae). Palaeoecological data suggest that deposition of the levels (Lak?árska Nová Ves Formation) from which these taxa were collected took place under generally low‐energy, deep‐water conditions that were conducive to the preservation of delicate structures. Palaeobiogeographical affinities of the described taxa suggest a trans‐Atlantic migration during the early Miocene.  相似文献   
37.
Numerical and functional impairment of circulating endothelial progenitor cells (EPCs) is thought to contribute to vascular aging and the associated increase in cardiovascular risk. We tested the following hypotheses: 1) EPC clonogenic and migratory capacity decrease progressively with age in healthy, sedentary adult men; and 2) regular aerobic exercise will improve EPC clonogenic and migratory capacity in previously sedentary middle-aged and older men. Peripheral blood samples were collected from 46 healthy sedentary men: 10 young (26 +/- 1 yr), 15 middle-aged (47 +/- 1 yr), and 21 older (63 +/- 1 yr). Mononuclear cells were isolated and preplated for 2 days, and nonadherent cells were further cultured for 7 days to determine EPC colony-forming units. Migratory activity of EPCs was determined using a modified Boyden chamber. Ten sedentary middle-aged and older men (59 +/- 3 yr) were studied before and after a 3-mo aerobic exercise intervention. The number of EPC colony-forming units was approximately 75% lower (P < 0.01) in middle-aged (12 +/- 3) and older (8 +/- 2) compared with young (40 +/- 7) men. There was no difference in colony count between middle-aged and older men. EPC migration (fluorescent units) was significantly reduced in older (453 +/- 72) compared with young (813 +/- 114) and middle-aged (760 +/- 114) men. The exercise intervention increased (P < 0.05) both EPC colony-forming units (10 +/- 3 to 22 +/- 5) and migratory activity (683 +/- 96 to 1,022 +/- 123) in previously sedentary middle-aged and older men. These results provide further evidence that aging adversely affects EPC function. Regular aerobic-endurance exercise, however, is an effective lifestyle intervention strategy for improving EPC clonogenic and migratory capacity in middle-aged and older healthy men.  相似文献   
38.
Fad35R from Mycobacterium tuberculosis binds to the promoter site of Fad35 operon and its DNA binding activities are reduced in the presence of tetracycline and palmitoyl-CoA. We resolved the crystal structure of Fad35R using single-wavelength anomalous diffraction method (SAD). Fad35R comprises canonical DNA binding domain (DBD) and ligand binding domain (LBD), but displays several distinct structural features. Two recognition helices of two monomers in the homodimer are separated by ~ 48 Å and two core triangle-shaped ligand binding cavities are well exposed to solvent. Structural comparison with DesT and QacR structures suggests that ligand binding-induced movement of α7, which adopts a straight conformation in the Fad35R, may be crucial to switch the conformational states between repressive and derepressive forms. Two DBDs are packed asymmetrically, creating an alternative dimer interface which coincides with the possible tetramer interface that connects the two canonical dimers. Quaternary state of alternative dimer mimics a closed-state structure in which two recognition helices are distanced at ~ 35 Å and ligand binding pockets are inaccessible. Results of biophysical studies indicate that Fad35R has the propensity to oligomerize in solution in the presence of tetracycline. We present the first structure of a FadR homologue from mycobacterium and the structure reveals DNA and ligand binding features of Fad35R and also provides a view on alternative quaternary states that mimic open and closed forms of the regulator.  相似文献   
39.
Quantitation of the expression of cell surface antigens has hitherto been limited to analysis by either cytotoxicity tests or radioimmune assays (5, 15). We report here the use of a new methodology to analyze and quantitate the expression of mouse histocompabililty antigens (H-2 locus) in hybrid clones and parental cell types. The binding of fluorescein-tagged antibody is measured on a cell-to-cell basis in large viable cell populations using flow microfluorimetric techniques. These techniques have been used to measure hapten and immunoglobulin binding to lymphocyte populations (8, 9, 14). However, this is the first report in which these techniques have been used to examine the expression of the H-2 locus. The advantage of this approach is twofold: first, a large and statistically significant sample population may be analyzed one cell at a time, thus revealing the fine detail of heterogeneity in the expression of the cell surface markers within a population. Second, as has been demonstrated for analysis of specific components of the immune system, this method does permit fluorescence-activated sorting of cell types according to their different surface populations (8, 9, 14).  相似文献   
40.
In contrast with the abundance of anatomical studies of secretory structures on aerial vegetative organs of Asteraceae species, the information about secretory structures on thickened subterranean organs is sparse. The aim of this study was to investigate the occurrence of secretory structures on thickened and nonthickened subterranean organs of seven Asteraceae species from three tribes: Eupatorieae (Chromolaena squalida and Gyptis lanigera), Vernonieae (Chresta sphaerocephala, Lessingianthus bardanoides, L. glabratus and Orthopappus angustifolius), and Plucheeae (Pterocaulon angustifolium). The specimens were collected in areas of cerrado from the State of São Paulo, Brazil. All species of the tribe Vernonieae studied exhibited endodermic cells, other than the epithelial cells of the canal, with secretory activity in the roots. In C. sphaerocephala roots, two types of endodermic cell were found, but only one had secretory activity. Secretory canals were found in the tuberous and nontuberous roots of all studied species. These data agree with the results from the literature for Asteraceae species. Here, we describe for the first time in Asteraceae the presence of secretory idioblasts in C. sphaerocephala. Secretory trichomes are present in the Orthopappus angustifolius rhizophore. Histochemical tests have shown that all types of secretory structure possess substances containing lipids. © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society, 2008, 157 , 789–796.  相似文献   
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