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31.
Doxorubicin (Dox) is an anthracycline antibiotic that is primarily used for treating various solid tumors including that of pulmonary, ovary, breast, uterine, cervix, and several blood cancers. However, nephrotoxicity associated with Dox treatment limits its clinical use. Administration of Dox in combination with compounds exhibiting antioxidant properties are being used to minimize the side effects of Dox. Diosmin is a flavonoid glycoside with numerous beneficial properties that is found in the pericarp of many citrus fruits. Diosmin has demonstrated antioxidant, anti-inflammatory, and anti-apoptotic effects in response to various insults, although the exact mechanism remains unknown. Therefore, this study was designed to evaluate the effect of diosmin in preventing kidney damage in response to Dox treatment. Male Wistar rats were randomly divided into four groups: control group, Dox group (20 mg/kg, i.p.), Dox plus low-dose diosmin group (100 mg/kg orally), and Dox plus high-dose diosmin group (200 mg/kg orally). A single intraperitoneal injection of Dox resulted in kidney damage as evidenced by significant alterations in kidney markers, histological abnormalities, and the attenuation of antioxidant defense mechanisms (GSH, SOD, and CAT). Moreover, Dox treatment significantly altered the expression of oxidative stress, inflammatory, and anti-apoptotic protein markers. Diosmin pretreatment alleviated Dox-induced nephrotoxicity by ameliorating the antioxidant mechanism, decreasing inflammation and apoptosis, and restoring kidney architecture. In conclusion, our results indicate that diosmin is a promising therapeutic agent for the prevention of nephrotoxicity associated with DOX.  相似文献   
32.
The present study, which was carried out at three localities in the Ozark Mountains of northwest Arkansas, investigated the effects of prescribed burning on wood-decomposing fungi using samples of decaying woody debris (DWD) placed in plastic incubation chambers. One of the localities had not been subjected to recent prescribed burning, whereas the other localities contained both an unburned area as well as an area recently subjected to burning. In all three localities, small pieces of decaying woody debris (DWD) were collected, placed in the incubation chambers and the latter kept moist for any extended period of time. Pieces of DWD collected in the areas subjected to burning typically displayed evidence of considerable charring. Fruiting bodies appearing in the incubation chambers were removed and identified by sequencing of ribosomal DNA region. A total of 101 specimens representing 80 different taxa were recorded in the entire investigation, but the numbers of both specimens and taxa were appreciably higher for the unburned collecting sites. As such, the data obtained indicate that prescribed burning lowers the species richness of the wood-decomposing fungi associated with DWD at a particular locality. The unique aspect of the present study was the use of incubation chambers to characterize the taxa of fungi associated with CWD.  相似文献   
33.
SARS-CoV-2 is a type of Betacoronaviruses responsible for COVID-19 pandemic disease, with more than 1.745 million fatalities globally as of December-2020. Genetically, it is considered the second largest genome of all RNA viruses with a 5′ cap and 3′ poly-A tail. Phylogenetic analyses of coronaviruses reveal that SARS-CoV-2 is genetically closely related to the Bat-SARS Like-Corona virus (Bat-SL-Cov) with 96% whole-genome identity. SARS-CoV-2 genome consists of 15 ORFs coded into 29 proteins. At the 5′ terminal of the genome, we have ORF1ab and ORF1a, which encode the 1ab and 1a polypeptides that are proteolytically cleaved into 16 different nonstructural proteins (NSPs). The 3′ terminal of the genome represents four structural (spike, envelope, matrix, and nucleocapsid) and nine accessory (3a, 3b, 6, 7a, 7b, 8b, 9a, 9b, and orf10) proteins. As the number of COVID-19 patients increases dramatically worldwide, there is an urgent need to find a quick and sensitive diagnostic tool for controlling the outbreak of SARS-CoV-2 in the community. Today, molecular testing methods utilizing viral genetic material (e.g., PCR) represent the crucial diagnostic tool for the SARS-CoV-2 virus despite its low sensitivity in the early stage of viral infection. This review summarizes the genome composition and genetic characterization of the SARS-CoV-2.  相似文献   
34.
In our search for new unconventional green-reducing agent, can be applied for biosynthesis of biologically active silver-nanoparticles, fruiting bodies (Ascocarps) of Truffle Terminia sp. were collected from the sandy desert of Hafr Al-Batin, Eastern Region, Saudi Arabia. The desert truffle showed the ability to reduce AgNO3 to Ag0 depending on their high content of proteins (1.74 mg/ml) in the aqueous extract of 30 mg/ml (w/v). The response surface methodology (RSM) with 13 experiments of 2–Factors–5–Levels central composite design was applied for controlling all possible combinations of AgNO3 concentrations and pH values of reaction mixture, which directly affect the particles morphology, size and biological activity. The antimicrobial effectiveness of all synthesized nanoparticles was evaluated against the pathogenic strains by agar diffusion method. The pathogenic Gram-positive Staphylococcus aureus, Bacillus subtilis, Lactobacillus cereus, and Gram-negative Escherichia coli, Salmonella enterica, yeast strain Candida albicans and the fungus Aspergillus niger were evaluated. The biologically active Truffle-AgNPs were characterized by UV–visible spectrophotometry, transmission electron microscopy (TEM), spectrum and dynamic light scatter (DLS), and Fourier Transformed Infrared (FTIR). Results obtained indicated that, the statistically controlled Truffle-AgNPs have great inhibitory role affecting different pathogenic strains, which gained much attention towards application of Hafr Al-Batin-Truffle as reducing and stabilizing biomaterial for green nano-drugs biosynthesis, to resist harmful pathogens threaten human health.  相似文献   
35.
Silymarin, a potential phytochemical compound obtained from the seeds of Silybum marianum plant has been used as a hepatoprotective agent for more than a decade. So far, eight active components of silymarin flavonolignans have been identified, among which silibinin has been proven the most active. However, it had poor oral bioavailability due to extensive phase II metabolism, low permeability across intestinal epithelial cells, low aqueous solubility, and rapid excretion in bile and urine. Therefore it becomes necessary to understand all its formulation and analytical aspects from past to present, including all of its possible future prospects. In modern research scenario, nanotization strategies of drugs has served as a potential approach to enhance solubility, bioavailability and to develop a robust formulation. Several approaches have been utilized previously to enhance the solubility and bioavailability of silymarin to provide it a robust strength against physical, chemical, and environmental degradation. Nanoscale formulations such as nanoemulsion, nanosuspension, liposomes, and solid–lipid nanoparticles can be used to enhance solubility and to target them to desired cells with minimum harm to normal cells. However, many other approaches exist such as dendrimers, ceramic nanoparticles, and carbon nanotubes, which serve as a great vehicle in drug delivery to transport medicament at target sites. Therefore, the purpose of this review was to develop a better understanding of the problems associated with silymarin and approaches to overcome the difficulties to develop a better and stable formulation for food and pharmaceutical applications.  相似文献   
36.
Patient protection has become one of the key elements of the quality of health care systems in Saudi Arabia. Medical errors that threaten patient safety are mediated by several factors including system risk factors. Hence, we used a self-structured questionnaire to assess and rank the system factors according to the perceptions of nurses working in the hospitals of the ministry of health in Hail, KSA. Eight out of twelve factors tested were perceived as threatening factors of the patient safety that are; ''Shortage of medical staff'', ''Poor design of the hospital structure'', ''Long working hours'', ''Overcrowding of patients'',''Poor coordination between hospital departments, ''Punitive and blaming environment, ''Lack of clinical practice standards'' and, ''Poor financial incentives''. Thus, considering the negative impact of the identified threatening system factors in this study on patient safety, urgent planning and managing appropriate corrective actions should be designed to improve patient safety issues.  相似文献   
37.
A number of alanine and more conservative mutants of residues in the fourth domain of thrombomodulin (TM) were prepared and assayed for protein C activation and for thrombin binding. Several of the alanine mutations appeared to cause misfolding or structural defects as assessed by poor expression and/or NMR HSQC experiments, while more conservative mutations at the same site appeared to allow correct folding and preserved activity. Several of the conservative mutants bound more weakly to thrombin despite the fact that the fourth domain does not directly contact thrombin in the crystal structure of the thrombin-TM complex. A few of the mutant TM fragments bound thrombin with an affinity similar to that of the wild type but exhibited decreases in k cat for protein C activation. These mutants were also less able to cause a change in the steady state fluorescence of fluorescein-EGR-chloromethylketone bound to the active site of thrombin. These results suggest that some residues within the fourth domain of TM may primarily interact with protein C but others are functionally important for altering the way TM interacts with thrombin. Residues in the fourth domain that primarily affect k cat for protein C activation may do this by changing the active site of thrombin.  相似文献   
38.
In this work, four fluorinated α, β-unsaturated ketones named as 3-(3-bromophenyl)−1-(3-(trifluoromethyl)phenyl)prop-2-en-1-one (1), 3-(4-methoxyphenyl)−1-(3-(trifluoromethyl)phenyl) prop-2-en-1-one (2), 3-(3-bromo-5-chloro-2-hydroxyphenyl)-1-(3-(trifluoromethyl)phenyl) prop-2-en-1-one (3) and 3-(2-hydroxy-5-methylphenyl)-1-(3-(trifluoromethyl)phenyl)prop-2-en-1-one (4) were synthesized by Claisen–Schmidt reaction. The synthesized molecules were then characterized through ultraviolet-visible spectroscopy (UV-Vis), Fourier transform infrared (FTIR), 1H-NMR, 13C-NMR, and mass spectrometry. The antioxidant potential, Urease inhibition, and interaction of compounds 1 – 4 with Salmon sperm DNA were experimentally explored and supported by molecular docking studies. The synthesized compounds strongly interact with SS-DNA through intercalative mode. It was noticed that compound 1 served as potent Urease inhibitor while compound 4 as better antioxidant among synthesized compounds. Moreover, frontier molecular orbitals, nonlinear optical (NLO) properties, natural bond orbitals, molecular electrostatic potential, natural population analysis, and photophysical properties of synthesized compounds were accomplished through density functional theory and time-dependent density functional theory. The band gap of all the compounds have been worked out using Taucs method. In addition to that, a precise comparative account of UV and IR data obtained from theoretical and experimental findings showed good agreement between theoretical and experimental data. The findings of our studies reflected that compounds  1 – 4 possess better NLO properties than Urea standard and the band gap data also reflected their prospective use towards optoelectronic materials. The better NLO behavior of compounds was attributed to the noncentrosymmetric structure of synthesized compounds.  相似文献   
39.
Type II diabetes mellitus (DM) and metabolic syndrome are associated with accelerated restenosis following vascular interventions due to neointimal hyperplasia. The efficacy of nitric oxide (NO)-based therapies is unknown in these environments. Therefore, the aim of this study is to examine the efficacy of NO in preventing neointimal hyperplasia in animal models of type II DM and metabolic syndrome and examine possible mechanisms for differences in outcomes. Aortic vascular smooth muscle cells (VSMC) were harvested from rodent models of type II DM (Zucker diabetic fatty), metabolic syndrome (obese Zucker), and their genetic control (lean Zucker). Interestingly, NO inhibited proliferation and induced G0/G1 cell cycle arrest to the greatest extent in VSMC from rodent models of metabolic syndrome and type II DM compared with controls. This heightened efficacy was associated with increased expression of cyclin-dependent kinase inhibitor p21, but not p27. Using the rat carotid artery injury model to assess the efficacy of NO in vivo, we found that the NO donor PROLI/NO inhibited neointimal hyperplasia to the greatest extent in type II DM rodents, followed by metabolic syndrome, then controls. Increased neointimal hyperplasia correlated with increased reactive oxygen species (ROS) production, as demonstrated by dihydroethidium staining, and NO inhibited this increase most in metabolic syndrome and DM. In conclusion, NO was surprisingly a more effective inhibitor of neointimal hyperplasia following arterial injury in type II DM and metabolic syndrome vs. control. This heightened efficacy may be secondary to greater inhibition of VSMC proliferation through cell cycle arrest and regulation of ROS expression, in addition to other possible unidentified mechanisms that deserve further exploration.  相似文献   
40.
Diabetic nephropathy (DN) is a serious kidney illness characterized by proteinuria, glomerular enlargement, reduced glomerular filtration, and renal fibrosis. DN is the most common cause of end-stage kidney disease, accounting for nearly one-third of all cases of diabetes worldwide. Hyperglycemia is a major factor in the onset and progression of diabetic nephropathy. Many contemporary medicines are derived from plants since they have therapeutic properties and are relatively free of adverse effects. Glycosides, alkaloids, terpenoids, and flavonoids are among the few chemical compounds found in plants that are utilized to treat diabetic nephropathy. The purpose of this review was to consolidate information on the clinical and pharmacological evidence supporting the use of a variety of medicinal plants to treat diabetic nephropathy.  相似文献   
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