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81.
BACKGROUND: Macrophage migration inhibitory factor (MIF) is a pluripotent cytokine involved in inflammation and immune responses as well as in cell growth. Although we previously demonstrated the presence of MIF in peripheral nerves, and MIF mRNA expression was up-regulated after axotomy, the role of MIF in nerve injury and regeneration has not been evaluated. MATERIALS AND METHODS: To examine the potential role of MIF in nerve regeneration, we locally administered an anti-MIF polyclonal antibody into regenerating rat sciatic nerves using the silicone chamber model. The effect of the anti-MIF antibody on nerve regeneration was evaluated using an axonal reflex test. In addition, we carried out a terminal deoxynucleotidyl transferase-mediated biotinylated UTP nick end labeling (TUNEL) assay and immunohistochemical analysis of the damaged nerve segments with regard to apoptosis-related proteins such as p53 to evaluate the effects of anti- MIF antibodies on apoptosis during the regeneration process. RESULTS: The regeneration length of the nerve in the anti-MIF antibody-treated group was significantly shorter than that in the non-immune rabbit IgG-treated group at weeks 2, 4 and 6 after surgery. TUNEL assay showed that a large number of apoptotic cells, mostly Schwann cells, were observed in the intratubal and distal nerve segments at weeks 4 and 6 after surgery by the anti-MIF antibody treatment. Consistent with these results, Ki-67-positive cells were significantly decreased by the anti-MIF antibody treatment. Immunohistochemical analyses revealed that p53 and, to a lesser extent, Fas were more up-regulated in the anti-MIF antibody-treated nerves than in the controls. CONCLUSION: Taken together, these results suggest that MIF plays an important role in acceleration of peripheral nerve regeneration and in prevention of Schwann cell apoptosis, mainly through overcoming the apoptotic effect of p53.  相似文献   
82.
In a previous study we determined that administration of recombinant feline interferon-omega (rFeIFN-omega) could protect Japanese pearl oysters Pinctada fucata martensii from akoya-virus infection. Our results suggested that rFeIFN-omega enhanced the potential of agranulocytes to phagocytize necrotic cells and to produce collagen fibers that repair the lesions caused by the akoya-virus. In the present study, using an indirect immunofluorescence technique with an anti-rFeIFN-omega rabbit serum, we examined whether hemocytes bear receptors that bind rFeIFN-omega. rFeIFN-omega receptors were present on agranulocytes and bound rFeIFN-omega, and appeared as green fluorescent spots in the cytoplasm under a fluorescent microscope. Around 56% of agranulocytes in Japanese pearl oysters bore the rFeIFN-omega receptors.  相似文献   
83.
We investigated the relationships between the ability to maintain balance in an upright stance and center-of-pressure (COP) dynamic properties in young adults. Included in this study were 10 healthy male subjects in each of two groups with respect to balance ability. Balance ability was evaluated according to the length of time a subject stood on one leg with his eyes closed. The means and ranges of this one-leg balancing time were 17.9 s (3-43 s) and 118.3 s (103-120 s) for the off-balance and balance groups, respectively. The time-varying displacements of the COP under a subject's feet during quiet two-leg (normal) standing were measured by an instrumented force platform. Each subject was tested in both the eyes-open and eyes-closed conditions. The COP trajectories were analyzed as fractional Brownian motions according to the procedure of 'stabilogram-diffusion analysis', proposed by Collins and De Luca (1993). The extracted parameters were the effective diffusion coefficients (D) for the short-term (less than about 1.0 s) and long-term intervals, respectively, as well as the Hurst exponents (H) for the short-term and long-term intervals, and some critical-point coordinates (i.e., critical mean square displacements and critical time intervals). The off-balance group showed significantly higher values for short-term D, short-term H, and critical mean square displacements than the balance group. No significant differences between the groups were found in the long-term D and H or in the critical time intervals. That is, for the off-balance subjects, an increase in the stochastic activity and positively correlated (persistent) behavior of the postural sway during shorter timescales may cause postural instability. These results suggest that the difference in balance ability for young adults is related to the open-loop (i.e., short-term) control mechanisms but not to the corrective feedback (i.e., long-term) mechanisms used to maintain balance in an upright stance.  相似文献   
84.
85.
To investigate the association of viral infections with chronic fatigue syndrome (CFS), we assayed 2', 5'-oligoadenylate synthetase (2-5AS) activities in peripheral blood mononuclear cells from CFS patients in Japan. These patients were diagnosed in two hospitals, H1 and H2, located in different areas of the country. The activities were detected in 19 (86%) and 7 (32%) of each of the 22 patients in H1 and H2, respectively, while they were detected in only four (11%) out of the 38 healthy controls. IFN-alpha was similarly detected in a few CFS patients and healthy controls. We also assayed the antibody titers against Epstein-Barr virus (EBV) and Coxiella burnetii in these patients. The EBV anti-EA-IgG antibodies were detected in two (9%) and seven (32%) of each of the 22 patients in H1 and H2, respectively. Anti-C. burnetii IgG antibodies were detected in six (27%) out of 22 patients in H1 but not in 22 patients in H2, while they were detected in one (11%) of the nine healthy controls. Some CFS patients may be associated with EBV or C. burnetii infection. There were some statistical correlations between the 2-5AS activities and antibody titers of EA-IgG (P < 0.05, Student's t-test) but not to the antibody titers of C. burnetii. The up-regulation of 2-5AS activities suggests immunological dysfunctions with some virus infections in the CFS patients. Our results indicate that 2-5AS activities are useful for a diagnostic marker of CFS and for exploring the complicated pathogenesis of CFS.  相似文献   
86.
Spirogyra living in running water is anchored to the substratum by rhizoids that form at the ends of the filaments. A new terminal cell differentiates into a rhizoid cell if the filament is injured. The mode of growth changes from diffuse to tip growth when rhizoid differentiation begins. In this study, we found that a callosic substance was synthesized during rhizoid differentiation. Decreasing the cell turgor, lowering extracellular Ca2+ or adding Gd3+, all inhibited the commencement of rhizoid differentiation as well as synthesis of the callose-like substance at the tip of the terminal cell. A callosic substance was also synthesized during formation of the conjugation tube.  相似文献   
87.
Injection of the glutamate agonist N-methyl-D-aspartate (NMDA) into the vitreous body of rats resulted in severe degeneration of neurons in the retina, with a loss of 81% of ganglion cells and 43% of non-ganglion cells. The cocktail EM-X is a novel antioxidant drink derived from ferment of unpolished rice, papaya and sea-weeds with effective microorganisms (EM-X). In animals treated with an intraperitoneal injection of EM-X, the loss of ganglion cells was reduced to 55% and that of non-ganglion cells to 34% when compared to untreated NMDA-injected retinas. Cell degeneration resulting from NMDA excitotoxicity, is thought to be mediated via oxidative stress mechanisms. The neuroprotective effect of the EM-X in this system is therefore likely to be due, at least in part, to its flavonoids, saponins, vitamin E and ascorbic content.  相似文献   
88.
Overproduced proteins from Escherichia coli BL21(DE3) were efficiently released with virulent bacteriophages. Leviviridae-like bacteriophages were isolated from soil and used to lyse BL21(DE3) cells transformed with beta-glucosidase, chitinase, or chitosanase genes. This method caused lysis of bacterial cells similar to that by conventional sonication and enabled us to effectively recover and purify the enzymes.  相似文献   
89.
The EtOAc extract of licorice (Glycyrrhiza uralensis roots) exhibited considerable PPAR-gamma ligand-binding activity. Bioassay-guided fractionation of the extract using a GAL-4-PPAR-gamma chimera assay method resulted in the isolation of two isoflavenes, one of which is a new compound named dehydroglyasperin D, an isoflavan, two 3-arylcoumarins, and an isoflavanone as the PPAR-gamma ligand-binding active ingredients of licorice. The isoprenyl group at C-6 and the C-2' hydroxyl group in the aromatic ring-C part in the isoflavan, isoflavene, or arylcoumarin skeleton were found to be the structural requirements for PPAR-gamma ligand-binding activity. Glycyrin, one of the main PPAR-gamma ligands of licorice, significantly decreased the blood glucose levels of genetically diabetic KK-A(y) mice.  相似文献   
90.
Oxidative stress and dysregulated cholesterol metabolism are characteristic features of chronic hepatitis C virus infection (CHC). Therefore, we analyzed serum oxysterol profiles in CHC patients and examined the significance of oxysterols in CHC. The concentrations of 7α-hydroxycholesterol, 4β-hydroxycholesterol and 25-hydroxycholesterol as determined by LC–ESI–MS/MS were significantly elevated by +236%, +29% and +44%, respectively, in CHC patients compared with controls. Moreover, the elevated levels were significantly decreased by anti-viral therapy using PEGylated-interferon and ribavirin for 3 months. In contrast, 24S-hydroxycholesterol, 27-hydroxycholesterol and 7α-hydroxy-4-cholesten-3-one concentrations were not affected by CHC or anti-viral treatment. These results suggest that some oxysterols that are elevated in CHC are produced by cholesterol autoxidation due to oxidative stress or inflammation in the liver. Oxysterols may represent novel targets for the inhibition of disease progression and the prevention of hepatocarcinogenesis in CHC patients.  相似文献   
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