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51.
Human carbonic anhydrase I and II isoenzymes (hCA I and II) and acetylcholinesterase (AChE) are important metabolic enzymes that are closely associated with various physiological and pathological processes. In this study, we investigated the inhibition effects of some sulfonamides on hCA I, hCA II, and AChE enzymes. Both hCA isoenzymes were purified by Sepharose‐4B‐L‐Tyrosine‐5‐amino‐2‐methylbenzenesulfonamide affinity column chromatography with 1393.44 and 1223.09‐folds, respectively. Also, some inhibition parameters including IC50 and Ki values were determined. Sulfonamide compounds showed IC 50 values of in the range of 55.14 to 562.62 nM against hCA I, 55.99 to 261.96 nM against hCA II, and 98.65 to 283.31 nM against AChE. Ki values were in the range of 23.40 ± 9.10 to 365.35 ± 24.42 nM against hCA I, 45.87 ± 5.04 to 230.08 ± 92.23 nM against hCA II, and 16.00 ± 45.53 to 157.00 ± 4.02 nM against AChE. As a result, sulfonamides had potent inhibition effects on these enzymes. Therefore, we believe that these results may contribute to the development of new drugs particularly in the treatment of some disorders.  相似文献   
52.
Aydın  Bilge  Yuca  Hafize  Karakaya  Songul  Bona  Gülnur Ekşi  Göger  Gamze  Tekman  Enes  Şahin  Aydan Acar  Sytar  Oksana  Civas  Ayşe  Canlı  Deniz  Pınar  Nur Münevver  Guvenalp  Zuhal 《Protoplasma》2023,260(2):371-389
Protoplasma - Scilla siberica subsp. armena is known as Siberian Squill which is naturally distributed in Lebanon-Syria, Transcaucasus, and Turkey. It is a perennial bulbous plant with a short...  相似文献   
53.
Bozkurt FY  Yetkin Ay Z  Berker E  Tepe E  Akkuş S 《Cytokine》2006,35(3-4):180-185
Cytokines which are produced by host cells play an important role in pathogenesis both rheumatoid arthritis (RA) and chronic periodontitis (CP). In this study, we aim to investigate the levels of Interleukin (IL)-4 and IL-10 in gingival crevicular fluid (GCF). Seventeen patients with CP, 17 patients with RA and 17 healthy controls (HC) were included. The RA group was divided into two groups according to gingival sulcus depths (RA-a: PD < or =3mm, (n=12), RA-b: PD>3mm, (n=5)). For each patient, clinical parameters were recorded. The GCF samples were evaluated by enzyme-linked immunosorbent assay (ELISA) for IL-4 and IL-10 levels. IL-4 levels in the RA-a, RA-b and CP subjects were significantly lower compared to the HC subjects (p<0.05). The mean level of IL-4 in RA-b group was significantly higher than that in CP group (p<0.05). IL-10 mean level in the HC group was higher than those in the other groups (p<0.05). In the RA-a group, higher IL-10 level was found compared to the CP patients (p<0.05). Within the limitations of this preliminary report, it can be concluded that the initiation and progression of periodontal inflammation may be due to a lack or inappropriate response of the anti-inflammatory cytokines in both CP and RA.  相似文献   
54.
Oxidative stress is believed to play an important role in the pathogenesis of considerable number of complex diseases. The antioxidant enzymes catalase (CAT) and glutathione peroxidase (GPX) are important components of cell defense against oxidative stress, and polymorphisms in the genes which regulate their expression may contribute to differences in susceptibility of individuals to oxidative damage caused by reactive oxygen species. The aim of this study was to assess the distribution of CAT C-262T and GPX1 Pro198Leu genotypic variants in a Turkish population. Genotyping analyses of CAT and GPX1 were conducted in 250 unrelated, healthy volunteers by the PCR-RFLP assay. The allele frequencies were 0.784 (C) and 0.216 (T) for CAT and 0.636 (C) and 0.364 (T) for GPX1 Pro198Leu. The genotype frequencies were 0.632 (CC), 0.304 (CT), and 0.064 (TT) for CAT and 0.416 (CC), 0.44 (CT), and 0.144 (TT) for GPX1 Pro198Leu. The genotype frequencies did not deviate from Hardy–Weinberg equilibrium. The results are compared with those of other reported populations. They showed marked ethnic group differences.  相似文献   
55.
A dinuclear centrosymmetric copper(II) complex with the formula [Cu2(μ-maa)4(maaH)2] has been synthesized and experimentally characterized by IR, electronic spectroscopy, and X-ray single-crystal diffractometry. Starting from experimental X-ray geometry and using antiferromagnetic singlet ground state, gas phase geometry optimization was performed by density functional hybrid (B3LYP) method with 6-31G(d) and LANL2DZ basis sets. Gas-phase vibrational frequencies and single point energy (SPE) calculations have been carried out at the geometry-optimized structure. Molecular electrostatic potential calculated at the optimized geometry and natural bond orbital analysis data have been extracted from SPE output. The gas-phase electronic transitions of the title complex were investigated by the time dependent-density functional theory (TD-DFT) approach with the same theory employing LANL2DZ basis set. Also the calculated UV-Vis based upon TD-DFT results and IR spectra were simulated for comparison with the experimental ones.  相似文献   
56.
This report presents a case with partial trisomy 18q resulting from de novo unbalanced translocation of chromosomes 15 and 18 displaying the features of pure trisomy. This is the first reported case with partial trisomy 18q due to unbalanced translocation between chromosomes 15 and 18. Clinical findings of our case have been compared with the reported cases' had partial trisomy 18q and the importance to recognize the cases with chromosome abnormalities to give genetic counseling and prenatal diagnosis for subsequent pregnancies has emphasized.  相似文献   
57.
Naturally occurring CD4(+)CD25(+)FoxP3(+) T regulatory (Treg) cells require three distinct signals transduced via TCR, CD28, and IL-2R for their development and maintenance. These requirements served as the basis for several recently developed ex vivo expansion protocols that relied on the use of solid support-bound Abs to CD3 and CD28 in the presence of high dose IL-2. We report in this study that Treg cells up-regulate the expression of inducible costimulatory receptor 4-1BB in response to IL-2, and stimulation using this receptor via a novel form of 4-1BB ligand (4-1BBL) fused to a modified form of core streptavidin (SA-4-1BBL) was effective in expanding these cells up to 110-fold within 3 wk. Expanded cells up-regulated CD25, 4-1BB, and membranous TGF-beta, suppressed T cell proliferation, and prevented the rejection of allogeneic islets upon adoptive transfer into graft recipients. Importantly, SA-4-1BBL rendered CD4(+)CD25(-) T effector cells refractive to suppression by Treg cells. This dual function of signaling via 4-1BB, vis-à-vis Treg cell expansion and licensing T effector cells resistant to Treg cell suppression, as well as the up-regulation of 4-1BB by IL-2 may serve as important regulatory mechanisms for immune homeostasis following antigenic challenge. Stimulation using a soluble form of SA-4-1BBL represents a novel approach to expand Treg cells with potential therapeutic applications in autoimmunity and transplantation.  相似文献   
58.
The study was performed to evaluate whether magnesium sulfate could alter the degree of disruption of the blood-brain barrier (BBB) caused by hyperosmotic mannitol. Wistar adult female rats were infused with 25% mannitol into the left internal carotid artery. Each animal received intraperitoneally a 300 mg/kg loading dose of magnesium sulfate, dissolved in 0.9% saline, followed by a further 100 mg/kg dose. In the other group, intracarotid infusion of magnesium sulfate was performed at a dose of 150 mg/kg 10 min before mannitol administration. Evans blue (EB) dye was used as a marker of BBB disruption. The measured serum glucose and magnesium levels increased after mannitol and/or magnesium administration when compared with their initial values before treatment (P < 0.01). Water content of the left hemisphere was significantly increased by hyperosmotic mannitol (P < 0.01). The increased water content in the mannitol-perfused hemisphere was significantly decreased by magnesium treatment (P < 0.05). The content of EB dye in the mannitol-perfused hemisphere markedly increased when compared with the right hemisphere of the same brain (P < 0.01). The EB dye content in the mannitol-perfused hemisphere following both intraperitoneal and intraarterial administration of magnesium decreased when compared with mannitol alone (P < 0.01). We conclude that although magnesium sulfate administration by both intracarotid arterial and intraperitoneal routes attenuates BBB disruption caused by hyperosmolar mannitol, particularly intraperitoneal route of magnesium sulfate administration may provide a useful strategy to limit the transient osmotic opening of the BBB.  相似文献   
59.
The direct modulation of T cell responses is an emerging therapeutic strategy with the potential to modulate undesired immune responses including, autoimmune disease, and allogeneic cells transplantation. We have previously demonstrated that poly(lactide-co-glycolide) particles were able to modulate T cell responses indirectly through antigen-presenting cells (APCs). In this report, we investigated the design of nanoparticles that can directly interact and modulate T cells by coating the membranes from APCs onto nanoparticles to form membrane-coated nanoparticles (MCNPs). Proteins within the membranes of the APCs, such as Major Histocompatibility Complex class II and co-stimulatory factors, were effectively transferred to the MCNP. Using alloreactive T cell models, MCNP derived from allogeneic dendritic cells were able to stimulate proliferation, which was not observed with membranes from syngeneic dendritic cells and influenced cytokine secretion. Furthermore, we investigated the engineering of the membranes either on the dendritic cells or postfabrication of MCNP. Engineered membranes could be to promote antigen-specific responses, to differentially activate T cells, or to directly induce apoptosis. Collectively, MCNPs represent a tunable platform that can directly interact with and modulate T cell responses.  相似文献   
60.
Novel chiral benzimidazole amine hybrids ( 4a – 4d ) were synthesized from commercially available amine [(R)- (+)-phenylethylamine, (−) (S)-(-)-phenylethylamine, (−) (R)-(-)-cyclohexylethylamine, (S)-(+)-cyclohexylethylamine] and 2-(chloromethyl)-N-tosyl-1H-benzimidazole. The synthesized compounds ( 4a – 4d ) were characterized by IR, NMR, and LC/MS analysis. The inhibitory effect of 4a – 4d on human erythrocytes carbonic anhydrase I (hCA-I), II (hCA-II), and acetylcholinesterase (AChE) activity was investigated. For hCA-I, the IC50 values of 4a – 4d were found to be 4.895 μM, 1.750 μM, 0.173 μM, and 0.620 μM, respectively, and for hCA-II, the IC50 values of 4a – 4d were found to be 0.469 μM, 0.380 μM, 0.233 μM, 0.635 μM, respectively. Furthermore, IC50 values of 4a – 4d on AChE were found as 87.5 nM, 100 nM, 26.92 nM, and 100 nM, respectively. In addition, molecular docking analysis was performed to evaluate the affinity of 4a – 4d against hCA-I, hCA-II, and AChE and explain their binding interactions.  相似文献   
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