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71.
The potential effects of flavonoids, phenylethanoid and neolignan glycosides from the aerial parts of Verbascum salviifolium Boiss. were studied in the p-benzoquinone-induced writhing reflex, for the assessment of the antinociceptive activity, and in carrageenan- and PGE1-induced hind paw edema and 12-O-tetradecanoyl-13-acetate (TPA)-induced ear edema models in mice, for the assessment of the anti-inflammatory activity. Through bioassay-guided fractionation and isolation procedures ten compounds from the aqueous extract of the plant, luteolin 7-O-glucoside (1), luteolin 3'-O-glucoside (2), apigenin 7-O-glucoside (3), chrysoeriol 7-O-glucoside (4), beta-hydroxyacteoside (5), martynoside (6), forsythoside B (7), angoroside A (8), dehydrodiconiferyl alcohol-9'-O-beta-D-glucopyranoside (9) and dehydrodiconiferyl alcohol-9-O-beta-D-glucopyranoside (10), were isolated and their structures were elucidated by spectral techniques. Results have shown that 1, 2, 3 and 5 significantly inhibited carrageenan-induced paw edema at a 200 mg/kg dose, while 1, 2 and 5 also displayed anti-inflammatory activity against the PGE1-induced hind paw edema model. However, all the compounds showed no effect in the TPA-induced ear edema model. The compounds 1 and 2 also exhibited significant antinociceptive activity.  相似文献   
72.
Seroprevalence of equine babesiosis in the Black Sea region of Turkey   总被引:1,自引:0,他引:1  
The prevalence of Theileria equi and Babesia caballi was determined in equid blood samples in five provinces of the Black Sea region of Turkey by using the indirect fluorescent antibody test (IFAT). Of 153 samples, 53 (34.6%) and 33 (21.5%) were seropositive to B. caballi and T. equi, respectively. In addition, 8 (5.2%) of samples were seropositive to both T. equi and B. caballi. Anti T. equi and B. caballi antibodies were detected in all five regions. The prevalence of B. caballi was higher than T. equi in all counties. Antibodies to T. equi and B. caballi were detected in horses of all ages, and there were no significant differences among age groups. Out of 84 horses, 32 (38.0%) were positive for B. caballi infection and 20 (23.8%) were positive for T. equi infection. Five horses (5.6%) were found to be seropositive to both B. caballi and T. equi. Of 38 donkeys, 14 (36.8%) were found to be positive for B. caballi infection and 5 (13.1%) positive for T. equi infection. In addition, 2 (5.2%) samples were seropositive for both T. equi and B. caballi infections. Out of 31 mules, 8 (25.8%) were positive for B. caballi infection and 8 (25 8%) positive for T. equi infection. One (3.2%) sample was seropositive for both T. equi and B. caballi infections. Of all the animals in this study, only 3 horses were infected by Rhipicephalus turanicus and Hyalomma detritum, and no haemoparasites were detected by microscopic examination.  相似文献   
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74.
The genus Cyclamen (family Myrsinaceae) contains about 20 species, most of which occur in the Mediterranean region. Turkey has critically important Cyclamen genetic resources. Molecular characterization of plant materials collected from different regions of Turkey in which Cyclamen species grow naturally, namely Adana, Antalya, Ayd?n, Mu?la, ?zmir, Denizli, Kahramanmara?, Osmaniye, Eski?ehir, Trabzon, and Rize provinces, was performed using RAPD and SRAP markers. DNA was successfully amplified by 30 RAPD primers and 14 SRAP primer pairs. Among the 470 bands generated by the RAPD primers, 467 were polymorphic. The number of bands detected by a single primer set ranged from 11 to 22 (average of 15.6). The percentage polymorphism was 99.3 % based on the RAPD data. In the SRAP analysis, a total of 216 bands were generated, showing 100 % polymorphism. The number of bands detected by a single primer set ranged from 9 to 22 (average of 15.4). All data were scored and UPGMA dendrograms were constructed with similar results in both marker systems, i.e., different species from nine provinces of Turkey were separated from each other in the dendrograms with the same species being clustered together.  相似文献   
75.
In the brain, the expression of 5-lipoxygenase (5-LO), the enzyme responsible for the synthesis of inflammatory leukotrienes, increases during aging. Antiinflammatory drugs are currently being evaluated for the treatment of aging-associated neurodegenerative diseases such as Alzheimer's disease. Although generally considered antiinflammatory, glucocorticoids, whose production also increases during aging, are not particularly effective in this disease. In human monocytes, 5-LO mRNA content increases on exposure to the synthetic glucocorticoid dexamethasone, which prompted us to hypothesize that glucocorticoids might increase 5-LO expression in the brain as well. We treated rats for 10 days either with corticosterone (implanted subcutaneously) or with dexamethasone (injected daily); they were killed on day 10 after pellet implantation or 24 h after the 10th dexamethasone injection. We found increased levels of 5-LO mRNA and protein in hippocampus and cerebellum of glucocorticoid-treated rats; 5-LO-activating protein (FLAP) mRNA content was not affected. Using western immunobloting, we also observed the concurrent translocation of 5-LO protein from cytosol to membrane, an indication of its activation. Thus, glucocorticoid-mediated up-regulation of the neuronal 5-LO pathway may contribute to rendering an aging brain vulnerable to degeneration.  相似文献   
76.
Abstract: Tryptophan hydroxylase, the initial and rate-limiting enzyme in the biosynthesis of the neurotransmitter serotonin, is activated by protein kinase A and calcium/calmodulin-dependent protein kinase. One important aspect of the regulation of any enzyme by a phosphorylation-dephosphorylation cascade, and one that is lacking for tryptophan hydroxylase, lies in the identification of its site of phosphorylation by protein kinases. Recombinant forms of brain tryptophan hydroxylase were expressed as glutathione S -transferase fusion proteins and exposed to protein kinase A. This protein kinase phosphorylates and activates full-length tryptophan hydroxylase. The inactive regulatory domain of the enzyme (corresponding to amino acids 1–98) was also phosphorylated by protein kinase A. The catalytic core of the hydroxylase (amino acids 99–444), which expresses high levels of enzyme activity, was neither phosphorylated nor activated by protein kinase A. Conversion of serine-58 to arginine resulted in the expression of a full-length tryptophan hydroxylase mutant that, although remaining catalytically active, was neither phosphorylated nor activated by protein kinase A. These results indicate that the activation of tryptophan hydroxylase by protein kinase A is mediated by the phosphorylation of serine-58 within the regulatory domain of the enzyme.  相似文献   
77.
78.

Background  

We propose an efficient and biologically sensitive algorithm based on repeated random walks (RRW) for discovering functional modules, e.g., complexes and pathways, within large-scale protein networks. Compared to existing cluster identification techniques, RRW implicitly makes use of network topology, edge weights, and long range interactions between proteins.  相似文献   
79.
DNA cytosine methylation in mammals modulates gene expression and chromatin accessibility. It also impacts mutation rates, via spontaneous oxidative deamination of 5-methylcytosine (5mC) to thymine. In most cases the resulting T:G mismatches are repaired, following T excision by one of the thymine DNA glycosylases, TDG or MBD4. We found that C-to-T mutations are enriched in the binding sites of CCAAT/enhancer binding proteins (CEBP). Within a CEBP site, the presence of a T:G mismatch increased CEBPβ binding affinity by a factor of >60 relative to the normal C:G base pair. This enhanced binding to a mismatch inhibits its repair by both TDG and MBD4 in vitro. Furthermore, repair of the deamination product of unmethylated cytosine, which yields a U:G DNA mismatch that is normally repaired via uracil DNA glycosylase, is also inhibited by CEBPβ binding. Passage of a replication fork over either a T:G or U:G mismatch, before repair can occur, results in a C-to-T mutation in one of the daughter duplexes. Our study thus provides a plausible mechanism for accumulation of C-to-T human somatic mutations.  相似文献   
80.
Marine sewage outfalls are the cheapest method of disposal for municipalities with restricted funds, despite their negative effects on marine ecosystems. This study was conducted on the marine sewage outfalls of the Turkish cities Rize (Black Sea) and Yalova (Sea of Marmara). Heavy metals, polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and organochlorine pesticides (OCPs) were investigated in the sediments for determine pollution degree. Two of Yalova stations were classified as having high contamination levels (1034.436 and 1476.483 ng/g, respectively) and all the other stations suffered moderate pollution in terms of ∑16PAHs. ∑DTTs in sediments above probable effect levels (PELs), were observed both stations Yalova and Rize. The highest metal concentrations in the sediments from the eight stations ranged from 4.97 to 29.65 mg/kg for Ni; 7.57–44.14 mg/kg for Cr; 9.84–42.76 mg/kg for Cu; and 48.08–103.77 mg/kg for Zn. In sum, examination of pollutant sources provides clear evidence of an anthropogenic effect on the discharge environments.  相似文献   
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