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1.
The effect of transforming growth factor beta-1 (TGF02j6p1787464368/xxlarge946.gif" alt="beta" align="MIDDLE" BORDER="0">1) expression on fatty acid binding proteins was examined in control and two strains of gene targeted TGF02j6p1787464368/xxlarge946.gif" alt="beta" align="MIDDLE" BORDER="0">1-deficient mice. Homozygous TGF02j6p1787464368/xxlarge946.gif" alt="beta" align="MIDDLE" BORDER="0">1-deficient 129 × CF-1, expressing multifocal inflammatory syndrome, had 25% less liver fatty acid binding protein (L-FABP) when compared to control mice. The decrease in L-FABP expression was not due to multifocal inflammatory syndrome since homozygous TGF02j6p1787464368/xxlarge946.gif" alt="beta" align="MIDDLE" BORDER="0">1-deficient/immunodeficient C3H mice on a SLID background had 36% lower liver L-FABP than controls. This effect was developmentally related and specific to liver, but not the proximal intestine, where L-FABP is also expressed. Finally, the proximal intestine also expresses intestinal-FABP (1-FABP) which decreased 3-fold in the TGF02j6p1787464368/xxlarge946.gif" alt="beta" align="MIDDLE" BORDER="0">1-deficient/immunodeficient C3H mice only. Thus, TGF02j6p1787464368/xxlarge946.gif" alt="beta" align="MIDDLE" BORDER="0">1 appears to regulate the expression of L-FABP and I-FABP in the liver and the proximal intestine, respectively.Abbreviations L-FABP liver fatty acid binding protein - I-FABP intestinal fatty acid binding protein - TGF02j6p1787464368/xxlarge946.gif" alt="beta" align="MIDDLE" BORDER="0">1 transforming growth factor beta-1 - TNF-02j6p1787464368/xxlarge945.gif" alt="agr" align="BASELINE" BORDER="0"> tumor necrosis factor-02j6p1787464368/xxlarge945.gif" alt="agr" align="BASELINE" BORDER="0"> - MIP-02j6p1787464368/xxlarge945.gif" alt="agr" align="BASELINE" BORDER="0"> macrophage inflammatory protein-02j6p1787464368/xxlarge945.gif" alt="agr" align="BASELINE" BORDER="0"> - PMSF phenylmethyl sulfonyl fluoride - PBS phosphate buffered saline  相似文献   
2.
A Waseem  M Yaqoob  A Nabi 《Luminescence》2004,19(6):333-338
A simple and rapid fl ow injection method is reported for the determination of iron in blood serum after acid digestion with HNO3 and HClO4, based on luminol CL detection in the absence of added oxidant. The detection limit (3 s) was 1.0 nmol/L with a sample throughput of 120/h. The calibration graph was linear over the range 0.001-1.0 micromol/L (r2 = 0.9974), with relative standard deviations (RSD) (n = 4) in the range 3.2-5%. The effect of interfering cations (Ca(II), Mg(II), Cu(II), Cd(II), Pb(II), Mn(II), Zn(II), Ni(II), Co(II) and Fe(III)) and anions (Cl-, SO4(2-), HCO3-, NO3-, NO2-) were studied using a luminol CL system for Fe(II) determination. The method was applied to normal blood serum and the results (1.32 +/- 0.08-1.74 +/- 0.05 mg/L) were compared with those from a spectrophotometric reference method (1.34 +/- 0.06-1.80 +/- 0.10 mg/L), which agree fairly well with the overall reference range in blood.  相似文献   
3.
A triple-resonance NMR technique suitable for the determination ofcarbonyl-related couplings in polypeptide systems is introduced. Theapplication of three novel pulse sequences to uniformly13C/15N-enriched proteins yields E.COSY-likemultiplet patterns exhibiting either one of the3J(C02h4/xxlarge8242.gif" alt="prime" align="BASELINE" BORDER="0">i–1,Hi 02h4/xxlarge945.gif" alt="agr" align="BASELINE" BORDER="0">), 3J(C02h4/xxlarge8242.gif" alt="prime" align="BASELINE" BORDER="0">i–1,Ci 02h4/xxlarge946.gif" alt="beta" align="MIDDLE" BORDER="0">) and3J(C02h4/xxlarge8242.gif" alt="prime" align="BASELINE" BORDER="0">i–1,C02h4/xxlarge8242.gif" alt="prime" align="BASELINE" BORDER="0">i)coupling constants in the indirectly detected 13C02h4/xxlarge8242.gif" alt="prime" align="BASELINE" BORDER="0">dimension, depending on the passive spin selected. The experiments aredemonstrated with oxidized flavodoxin from Desulfovibrio vulgaris. On thebasis of the J-values measured and the backbone 02h4/xxlarge966.gif" alt="phgr" align="MIDDLE" BORDER="0">-angles derived from ahigh-resolution X-ray structure of the protein, the three associated Karplusequations were reparametrized. The root-mean-square differences between theexperimental coupling constants and those predicted by the optimized Karpluscurves are 0.41, 0.33 and 0.32 Hz for3J(C02h4/xxlarge8242.gif" alt="prime" align="BASELINE" BORDER="0">i–1,Hi 02h4/xxlarge945.gif" alt="agr" align="BASELINE" BORDER="0">),3J(C02h4/xxlarge8242.gif" alt="prime" align="BASELINE" BORDER="0">i–1,Ci 02h4/xxlarge946.gif" alt="beta" align="MIDDLE" BORDER="0">) and3J(C02h4/xxlarge8242.gif" alt="prime" align="BASELINE" BORDER="0">i–1,C02h4/xxlarge8242.gif" alt="prime" align="BASELINE" BORDER="0">i),respectively. The results are compared with the Karplus parameters previouslypublished for the same couplings.  相似文献   
4.
3H-Labeled leukotriene C3 was efficiently taken up by the isolated, perfused rat liver and excreted into the bile. The isolated, perfused kidney eliminated leukotriene C3 from the perfusate slower and excreted only a fraction of the radioactivity into the urine. Isolated hepatic, intestinal and renal cells also took up leukotriene C3, the renal cells being the most effective in accumulating the label. Anthglutin, an inhibitor of γ-glutamyl transferase, decreased the uptake by kidney cells but had no effect on the uptake by the other cell types. In liver cells, the uptake rate was sensitive to temperature and to cellular ATP content. Chromatographic analyses indicated that renal cells metabolized leukotriene C3 more rapidly than hepatic and intestinal cells. Leukotriene D3 and E3 were formed during the incubations with kidney cells, whereas intestinal cells produced mainly more polar metabolites.  相似文献   
5.
Macrophages have been found to suppress the in vitro production by stimulated T lymphocytes of a lymphokine, migration inhibitory factor. When macrophages isolated from primary MSV-induced tumors were added to antigen-stimulated MSV-immune spleen cells, a complete suppression of MIF production was observed. This suppression was nonspecific, since MIF production by antigen-stimulated alloimmune spleen cells and by PHA-stimulated normal spleen cells was also inhibited. Suppressor macrophages could also be induced by inoculation with Corynebacterium parvum, whereas light mineral oil-induced peritoneal macrophages had no detectable effect on MIF production. The failure to detect MIF in the supernatants of stimulated cultures containing activated macrophages appeared to be due to inhibition of lymphokine production rather than to absorption or inactivation of MIF or to interference with the assay for detection of MIF. Macrophages were able to suppress MIF production only when added during the first 4–5 hr of culture and they had no effect when added later. These data show that activated macrophages can nonspecifically suppress lymphokine production and that this appears to be due to inhibition of an early step in lymphocyte stimulation.  相似文献   
6.
7.
For 22 days after monocrotaline injection two groups of rats received either of the monocarbonyl curcumin analogs (2E,6E)‐2,6‐bis(2‐bromobenzylidene)cycloxehanone (B2BrBC) and (2E,6E)‐2,6‐bis([2‐tri?uoromethyl]benzylidene)cyclohexanone (C66), and their right ventricle parameters were compared to those from the control and the monocrotaline injected animals. B2BrBC and C66 treatments did not prevent the monocrotaline‐induced right ventricular hypertrophy but attenuated the changes in antioxidant enzyme activities and reduced inflammation. The level of thiol‐based nonenzymatic antioxidants did not change in the function of monocrotaline or curcumin analogs treatment. However, due to its stronger antioxidant properties, only B2BrBC treatment was effective in the reduction of monocrotaline‐associated lipid peroxidation. The obtained results suggest that increasing the levels of antioxidant enzymes may not be sufficient to reduce oxidative stress and chronic inflammation optimally and our current study supports the potential of compounds with more than one beneficial biological activity as a promising treatment against the progression of cardiac hypertrophy.  相似文献   
8.
Cellobiose dehydrogenase (CDH, EC 1.1.99.18) is a glycoprotein having many biotechnological applications. In the present study, CDHs isolated from Phlebia lindtneri (PlCDH), Phanerochaete chrysosporium (PchCDH), Cerrena unicolor (CuCDH), and Pycnoporus sanguineus (PsCDH) were studied the first time for their ability to generate antioxidant and antimicrobial agents. The aim of the research was to evaluate the antioxidant and antimicrobial activity of systems composed of four CDHs and lactose or cellobiose as a reaction substrate. The free radical scavenging effect of free and immobilised enzymes was evaluated using the DPPH method. The lowest values of EC50 (10.04 ± 0.75 μg/ml) was noted for PlCDH/lactose and for PlCDH/cellobiose (12.06 ± 1.35 μg/ml). The EC50value reached 12.6 ± 1.51 μg/ml in the case of PsCDH/lactose and 15.96 ± 1.35 for PsCDH. The CDH preparations were also effectively immobilised in alginate (the immobilisation efficiency expressed as a protein yield ranged from 61.6 to 100 %). The operational stability expressed as a scavenging effect showed the possibility of using the alginate beads 4 times. Both the free and immobilised CDHs as well as the CDH/substrate were tested against Gram-negative Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853, and Gram-positive Staphylococcus aureus ATCC 25923 bacteria. All samples, except PlCDH, were potentially effective in suppression of bacterial growth. The highest percentage of inhibition (100 %) was obtained for S. aureus bacteria using PsCDH and PchCDH with lactose as a substrate, whereas a slightly lesser effect was observed for E. coli and P. aeruginosa bacterial cells, i.e. 64.1 % and 86.5 % (PsCDH) and 94.1 % and 41.4 % (PchCDH), respectively. Furthermore, the concentrations of the reaction products (aldonic acids and hydrogen peroxide) were quantified and the surface morphology of the alginate beads was analysed using SEM visualisation.  相似文献   
9.
Three new fossils of saprotrophic fungi are presented and described from Baltic amber, dated to Eocene epoch (Paleogene, upper to mid-Eocene). All belong to Ascomycota and are represented by hyphae as well as asexual reproduction structures allowing to assign them to present genera, respectively Periconia, Penicillium and Scopulariopsis. These material provide both the first and the oldest known fossil record of the mentioned taxa, making these data valuable for the knowledge about the evolutionary history of the Ascomycota.  相似文献   
10.
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