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131.
Background:Diabetes-related vascular complications linked to increase in the expression of VEGF and its receptors. It helps to accelerate tissue damage inflicted by hyperglycemia, which is potential risk for diabetic complications. The study aimed to assess VEGF genetic polymorphism and its correlation with glucose and HbA1C level among Sudanese patients with diabetic retinopathy and nephropathy.Methods:A case-control study was conducted among a total of 252 subjects and divided into four groups of 63 subjects each. Glucose and HBA1c were measured then the VEGF gene was amplified using polymerase chain reaction. The data were analyzed using SPSS.Results:The HBA1c, and blood glucose levels had significantly (P value≤0.00001) highest mean in the DR group, DN group followed by DM. There is a non-significant correlation between VEGF Genotypes and HbA1c, and blood glucose levels (P value≤0.102, 0.173) Patients with GC genotypes will be 74.6%, and 54% higher at risk to develop DR, and DN respectively and 40 % lower at risk to develop DM than those without GC genotype. While patients with CC genotypes will be 22.2% higher at risk of developing DM and 9.5%, 12.2% higher at risk of developing DR and DN respectively.DiscussionThe VEGF +405G/C gene polymorphism is linked to diabetic retinopathy, and diabetic nephropathy in type 2 Sudanese diabetics, and the presence of the GC genotypes and G allele is a significant predictor for retinopathy. There is no significant relation between HbA1C serum levels, blood glucose, and the VEGF +405G/C gene polymorphism.Key Words: Diabetic Nephropathy, Diabetic Retinopathy, Blood Glucose, HbA1c, Gene polymorphism, VEGF-A  相似文献   
132.
Thellungiella halophila seedlings grown on a solid substrate for 25 days on standard medium were challenged with NaCl. Growth, tissue hydration, ion accumulation, photosynthesis, lipid peroxidation and antioxidant enzymatic activities were studied on rosette leaves. Three accessions of Arabidopsis thaliana were cultivated under the same conditions. During the first two weeks of salt treatment, the growth of T. halophila leaves was restricted by NaCl. No significant difference appeared between T. halophila and A. thaliana concerning biomass deposition, or hydric and ionic parameters. However, all A. thaliana plants displayed foliar damage, and died during the third week of salt (50mM NaCl) treatment. Almost all (94%) T. halophila plants remained alive, but did not display any sign of altered physiological condition. Tissue hydration, chlorophyll content, stomatal conductance, photosynthetic quantum yield, and photosynthetic rate were very similar to those of control plants. Lipid peroxidation, estimated from thermoluminescence, was very low and insensitive to salt treatment. Only slight changes occurred in antioxidant enzymatic activities (SOD, several peroxidases, and catalase). From the absence of physiological disorder symptoms, we infer that salt was efficiently compartmentalized in leaf vacuoles. In salt-treated A. thaliana, the photosynthetic quantum yield was diminished, and lipid peroxidation was augmented. These observations reinforce the conclusion that T. halophila could accumulate salt in its leaves without damage, in contrast to A. thaliana.  相似文献   
133.
Microsupercapacitors (MSCs) with high energy densities offer viable miniaturized alternatives to bulky electrolytic capacitors if the former can respond at the kilo Hertz (kHz) or higher frequencies. Moreover, MSCs fabricated on a chip can be integrated into thin‐film electronics in a compatible manner, serving the function of ripple filtering units or harvesters of energy from high‐frequency sources. In this work, wafer‐scale fabrication is demonstrated of MXene microsupercapacitors with controlled flake sizes and engineered device designs to achieve excellent frequency filtering performance. Specifically, the devices (100 nm thick electrodes and 10 µm interspace) deliver high volumetric capacitance (30 F cm?3 at 120 Hz), high rate capability (300 V s?1), and a very short relaxation time constant (τ0 = 0.45 ms), surpassing conventional electrolytic capacitors (τ0 = 0.8 ms). As a result, the devices are capable of filtering 120 Hz ripples produced by AC line power at a frequency of 60 Hz. This study opens new avenues for exploring miniaturized MXene MSCs as replacements for bulky electrolytic capacitors.  相似文献   
134.
Conductive 2D metal–organic frameworks (MOFs) have merits beyond traditional MOFs for electrochemical applications, but reports on using MOFs as electrodes for electrochemical microsupercapacitors (MSCs) are practically non‐existent. In this work, a Ni‐catecholate‐based MOF (Ni‐CAT MOF) having good conductivity and exhibiting redox chemistry in the positive and negative voltage windows is developed. A novel process is developed to selectively grow the conductive Ni‐CAT MOF on 3D laser scribed graphene (LSG). The LSG with its superior wettability serves as a functional matrix‐current collector for the hybridization of conductive Ni‐CAT MOF nanocrystals. Impressively, MSCs fabricated using the hybrid LSG/Ni‐CAT MOF show significant improvement compared with MOF‐free LSG electrodes. Specifically, the LSG/Ni‐CAT MOF electrodes can deliver MSCs with a wide operating voltage (1.4 V), high areal capacitance (15.2 mF cm?2), energy density (4.1 µWh cm?2), power density (7 mW cm?2), good rate performance, and decent cycling stability. This work opens up an avenue for developing electrochemical microsupercapacitors using conductive MOF electrodes.  相似文献   
135.
Angiopoietin-1 (Ang-1) is a ligand for Tie-2 receptors and a promoter of angiogenesis. Angiogenesis plays an important role in breast cancer, as it is one of the critical events required for tumors to grow and metastasize. In this study, we investigated the influence of estradiol (E2) on the expression of angiopoietins in breast cancer cell lines. Ang-1 mRNA and protein expressions were significantly higher in estrogen receptor-negative (ERα-) breast cancer cells than in estrogen receptor-positive (ERα+) cells. Exposure of ERα+ cells to E2 resulted in further reductions of Ang-1 levels. In mouse mammary pads inoculated with breast cancer cells, both tumor size and Ang-1 production were significantly lower in ERα+ cell-derived xenografts, as compared to those derived from ERα- cells. Reduction of circulating levels of E2 by ovariectomy eliminated this response. Overall, these results indicate that Ang-1 mRNA and protein expressions: (1) negatively correlate with the level of ERα in breast cancer cell lines; (2) are downregulated by E2 in an ERα dependent manner; and (3) positively correlate with the degree of angiogenesis in vivo. We conclude that Ang-1 is an important modulator of growth and progression of ERα- breast cancers.  相似文献   
136.
Thellungiella halophila and Arabidopsis thaliana were irrigated with medium containing NaCl at various concentrations. The salt treatment resulted in a restriction of rosette biomass deposition in both species. In A. thaliana leaves, this inhibition was stronger than for T. halophila and was associated with strong inhibition of both leaf initiation and leaf expansion. At highest medium salinity, A. thaliana accumulated Na(+) and Cl(-) at higher levels than T. halophila, but similar leaf dehydration was observed in the two species. Proline accumulation, which increased with NaCl concentration, did not differentiate the two species. The magnitude of the electrolyte leakage and the level of lipid peroxidation (assessed through hydroxy fatty acid content) were modest in T. halophila and quite marked in A. thaliana. The detrimental effects of the salt on photosynthetic activity and stomatal conductance of A. thaliana leaves were much more important than in T. halophila leaves. The abundance of the CDSP32 thioredoxin, a critical component of the defence system against oxidative damage and lipid peroxidation, was found to be higher in T. halophila than in A. thaliana under control conditions and salt treatment. These results suggest that the rosette leaves of T. halophila exhibit more efficient protective mechanisms against Na(+) metabolic toxicity than those of A. thaliana.  相似文献   
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139.
Because brain membranes contain large amounts of docosahexaenoic acid (DHA, 22:6n-3), and as (n-3) PUFA dietary deficiency can lead to impaired attention, learning, and memory performance in rodents, we have examined the influence of an (n-3) PUFA-deprived diet on the central cholinergic neurotransmission system. We have focused on several cholinergic neurochemical parameters in the frontal cortex and hippocampus of rats fed an (n-3) PUFA-deficient diet, compared with rats fed a control diet. The (n-3) PUFA deficiency resulted in changes in the membrane phospholipid compositions of both brain regions, with a dramatic loss (62-77%) of DHA. However, the cholinergic pathway was only modified in the hippocampus and not in the frontal cortex. The basal acetylcholine (ACh) release in the hippocampus of deficient rats was significantly (72%) higher than in controls, whereas the KCl-induced release was lower (34%). The (n-3) PUFA deprivation also caused a 10% reduction in muscarinic receptor binding. In contrast, acetylcholinesterase activity and the vesicular ACh transporter in both brain regions were unchanged. Thus, we evidenced that an (n-3) PUFA-deficient diet can affect cholinergic neurotransmission, probably via changes in the phospholipid PUFA composition.  相似文献   
140.
A sensitive, specific and selective method has been developed for the simultaneous determination of bisoprolol and hydrochlorothiazide in human plasma. The method employed a state of the art LC–MS/MS operated in the positive and negative ionization switching modes. A simple sample preparation step involving protein precipitation with acetonitrile has been optimized; the analytes and the internal standard moxifloxacin were separated on a Purosphere® STAR C8 column (125 mm × 4 mm, 5 μm). The mobile phase was an ammonium acetate solution (1 mM) with formic acid (0.2%): methanol and acetonitrile (65:17.5:17.5, v/v/v (%)), the flow rate was set at 0.65 mL/min. Bisoprolol and hydrochlorothiazide were ionized using ESI source prior to detection by Multiple Reaction Monitoring (MRM) mode while monitoring at the following transitions: positive m/z 326  116 for bisoprolol, negative m/z 296  269 and m/z 296  205 for hydrochlorothiazide. Linearity was demonstrated over the concentration range 0.10–30.0 (ng/mL) for bisoprolol and 1.00–80.00 ng/mL for hydrochlorothiazide. The limits of detection were 0.100 (ng/mL) for bisoprolol and 1.00 (ng/mL) for hydrochlorothiazide. The validated method was successfully applied to a pharmacokinetic study of 5 mg bisoprolol fumarate with 12.5 mg hydrochlorothiazide tablet in healthy volunteers.  相似文献   
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