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61.
σ(D) proteins from Aeribacillus pallidus AC6 and Bacillus subtilis bound specifically, albeit weakly, to promoter DNA even in the absence of core RNA polymerase. Binding required a conserved CG motif within the -10 element, and this motif is known to be recognized by σ region 2.4 and critical for promoter activity.  相似文献   
62.
The essential trace elements play important roles in the maintainance of the normal structure and physiology of cells. Several research groups have demonstrated that they also play important roles in states of cardiovascular diseases. Our aim is to investigate whether there is a relationship between trace elements (Zn and Cu) and the degree of atherosclerosis. The sample consisted of 67 patients with coronary artery disease and 26 clinically healthy individuals. Ninety-three subjects were separated into four groups according to their Gensini scores, the number of diseased vessels, the presence of acute coronary syndrome, and ejection fraction. Each group was divided into three subgroups, and serum zinc and copper levels were measured for each individual. The serum levels of zinc and copper were found to be significantly lower in patients with atherosclerosis than in the control group, but there were no significant differences in the serum levels of Cu and Zn between severe atherosclerosis and mild atherosclerosis. In Spearman's rank correlation, the zinc and copper levels were correlated with the Gensini score and the number of diseased vessels. The present study revealed a relationship between the serum levels of zinc and copper and atherosclerosis, but not between these levels and the severity of the disease.  相似文献   
63.
Carbonic anhydrase inhibitors (CAIs) are a class of pharmaceuticals used as antiglaucoma agents, diuretics, antiepileptics, in the management of mountain sickness, gastric and duodenal ulcers, neurological disorders or osteoporosis. We report here the inhibitory capacities of some phenolic compounds against three human CA isozymes (hCA I, hCA II, and hCA VI) and the gill carbonic anhydrase of the teleost fish Dicentrarchus labrax (European seabass) (dCA). The isozymes showed quite diverse inhibition profiles with these compounds. These data may lead to design novel CAIs with a diverse inhibition mechanism compared to sulfonamide/sulfamate inhibitors.  相似文献   
64.
No comparative study could be found for the analgesic activity of mucuses from the Oncorhynchus mykiss (OM), Salvelinus fontinalis (SF), Salmo coruhensis (SC), Acipenser gueldenstaedtii (AG), and Acipenser baerii (AB) fish species in the literature. We aimed to investigate the effects of mucuses obtained from the abovementioned fish species on scalpel incision-induced pain in the rat paw and to examine the role of oxidant/antioxidant parameters and COX-2 gene expression in the analgesic activities. Animals were divided into groups: SIC (scalpel incision; SI), SIDS (SI+25 mg/kg diclofenac sodium), SOM (SI+25 mg/kg OM mucus), SFM (SI+25 mg/kg SF mucus), SCM (SI+25 mg/kg SC mucus), SAgM (SI+25 mg/kg AG mucus), SAbM (SI+25 mg/kg AB mucus), and HG (healthy). The paw pain thresholds were measured with a Basile algesimeter before and after diclofenac sodium (DS) or mucus administration, and then the rats were euthanized with thiopental sodium. Oxidant/antioxidant and COX-2 gene expression parameters were measured in paw tissues. OM, SC, AG, and AB fish mucuses could not decrease the SI-induced pain. However, SF fish mucus prevented this pain by 69% after the first hour and by 58.3% after the third hour. DS was shown to suppress pain more weakly than SF, preventing the pain by 62.1% and 50.0% after the first and third hours, respectively. SF mucus and DS significantly inhibited increase of COX-2 gene expression, while other fish mucuses could not. None of the fish mucuses except SF mucus in conjunction with DS could significantly inhibit the increase in oxidant parameters and decrease in antioxidants. SF fish mucus should be comparatively assessed in clinical practice for treatment of postoperative pain.  相似文献   
65.
Heat treatment is often used to improve the dimensional stability of wood. In this study, the effects of heat treatment on technological properties of Red-bud maple (Acer trautvetteri Medw.) wood were examined. Samples obtained from Düzce Forest Enterprises, Turkey, were subjected to heat treatment at varying temperatures (120 degrees C, 150 degrees C and 180 degrees C) and for varying durations (2h, 6h and 10h). The technological properties of heat-treated wood samples and control samples were tested. Compression strength parallel to grain, bending strength, modulus of elasticity in bending, janka-hardness, impact bending strength, and tension strength perpendicular to grain were determined. The results showed that technological strength values decreased with increasing treatment temperature and treatment times. Red-bud maple wood could be utilized by using proper heat treatment techniques with minimal losses in strength values in areas where working, and stability such as in window frames, are important factors.  相似文献   
66.
Heat treatment is often used to improve the dimensional stability of wood. In this study, the effects of heat treatment on physical properties and surface roughness of Camiyani Black Pine (Pinus nigra Arn. subsp. pallasiana var. pallasiana) wood were examined. Samples obtained from Yenice-Zonguldak Forest Enterprises, Turkey, were subjected to heat treatment at varying temperatures and for varying durations. The physical properties of heat-treated and control samples were tested, and oven-dry density, air-dry density, and swelling properties were determined. The mechanical properties of heat-treated and control samples were tested, and compression strength, and Janka-hardness were determined. A stylus method was employed to evaluate the surface characteristics of the samples. Roughness measurements by the stylus method were made in the direction perpendicular to the fiber. Four main roughness parameters, mean arithmetic deviation of profile (Ra), mean peak-to-valley height (Rz), root mean square roughness (Rq), and maximum roughness (Ry) obtained from the surface of wood were used to evaluate the effect of heat treatment on the surface characteristics of the specimens. Significant difference was determined (p=0.05) between physical and technological properties, and surface roughness parameters (Ra, Rz, Ry, Rq) for three temperatures and three durations of heat treatment. Based on the findings in this study, the results showed that density, swelling, compression strength, Janka-hardness and surface roughness values decreased with increasing treatment temperature and treatment times. Increase in temperature and duration further diminished technological strength values of the wood specimens. Camiyani Black Pine wood could be utilized by using proper heat treatment techniques without any losses in strength values in areas where working, stability, and surface smoothness, such as in window frames, are important factors.  相似文献   
67.
Background The aim of this investigation was to demonstrate that benzyloxicarbonyl-l-phenylalanyl-alanine-fluoromethylketone (Z-FA.FMK), which is a pharmacological inhibitor of cathepsin B, has protective role on the kidney injury that occurs together with liver injury. Methods BALB/c male mice used in this study were divided into four groups. The first group was given physiologic saline only, the second group was administered Z-FA.FMK alone, the third group received d-galactosamine and tumor necrosis factor-alpha (d-GalN/TNF-α), and the fourth group was given both d-GalN/TNF-α and Z-FA.FMK. One hour after administration of 8 mg/kg Z-FA.FMK by intravenous injection, d-GalN (700 mg/kg) and TNF-α (15 μg/kg) were given by intraperitoneal injection. Results In the group given d-GalN/TNF-α, the following results were found: severe degenerative morphological changes in the kidney tissue, a significant increase in the number of activated caspase-3-positive tubular epithelial cell, an insignificant increase in the number of proliferating cell nuclear antigen (PCNA)-positive tubular epithelial cell, a decrease in the kidney glutathione (GSH) levels, catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities, an increase in the kidney lipid peroxidation (LPO) levels, lactate dehydrogenase (LDH) activity, serum aspartate aminotransferase (AST), and alanine aminotransferase (ALT) activities, uric acid and urea levels. In contrast, in the group given d-GalN/TNF-α and Z-FA.FMK, a significant decrease in the d-GalN/TNF-α-induced degenerative changes, a decrease in the number of activated caspase-3-positive tubular epithelial cell, a insignificant decrease in the number of PCNA-positive tubular epithelial cell, an increase in the kidney GSH levels, CAT, SOD and GPx activities, a decrease in the kidney LPO levels, LDH activity, serum AST and ALT activities, uric acid and urea levels were determined. Conclusion These results suggest that pretreatment with Z-FA.FMK markedly lessens the degree of impairment seen in d-GalN/TNF-α-induced kidney injury, which occurred together with liver injury in mice.  相似文献   
68.
The aim of this work was to investigate the biochemical and histological effects of vanadyl sulfate on blood glucose, urea, and creatinine in serum and nonenzymatic glycosylation and glutathione levels in kidney tissue of normal and streptozotocin (65 mg/kg) diabetic rats. Vanadyl sulfate was administered by gavage at a dose of 100 mg/kg. After 60 d of treatment, serum urea, creatinine, and blood glucose levels significantly increased in the diabetic group but not so in the vanadyl sulfate, which showed significantly reduced serum urea and blood glucose levels and a nonsignificant reduction of serum creatinine levels. Nonenzymatic glycosylation was increased and the glutathione level was decreased in the kidney tissue of diabetic rats. Treatment with vanadyl sulfate reversed these effects. Degenerative changes were detected in diabetic animals by electron and light microscopy. Although there are individual differences in diabetic animals given vanadium, some reduction of degenerative changes were observed.  相似文献   
69.
This study designs a prediction model to differentiate pasteurized milk from heated extended shelf life (ESL) milk based on milk peptides. For this purpose, quantitative peptide profiles of a training set of commercial samples including pasteurized (n = 20), pasteurized‐ESL (n = 13), and heated‐ESL (n = 16) milk are recorded by matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry (MALDI‐TOF‐MS). Seven peptides are selected as putative markers, and cutoff levels and performance measures of each marker are defined by receiver operating characteristic (ROC) analysis. The accuracy of these peptides in the training set range between 71% and 90%. A prediction model is established based on the combined cutoff levels and evaluated by an independent blind test set. The processing method of 19 out of 20 unknown milk samples is predicted correctly achieving 95% accuracy. Five peptides of the prediction model are identified as αS1‐casein182–199 (m/z 2014.0), αS1‐casein180–199 (m/z 2216.1), αS1‐casein1–24 (m/z 2910.6), β‐casein108–125 (m/z 2126.0), and β‐casein106–125 (m/z 2391.2) indicating thermal release and the action of plasmin and cathepsins. Thus, the present study demonstrates that the milk peptide profile reflects even minor differences in production parameters.  相似文献   
70.
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