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81.
In this study, we introduce the concept of semisimilarity and consemisimilarity of split quaternions. Moreover, we examine the solvability conditions and general solutions of systems \({xay=b,ybx=a {\rm and} \widetilde{x}ay=b,\widetilde{y}bx=a}\) in split quaternions. If there exist x and y that satisfy first equations system, then a and b are said to be semisimilar, if there exist x and y that satisfy second equations system, then a and b are said to be consemisimilar.  相似文献   
82.
Journal of Radioanalytical and Nuclear Chemistry - PAMAM dendrimers modified silica gel terminated phenylphosphonic acid-amide moieties (Si-6G PAMAM-PPAAM) was prepared for uranium(VI) adsorption...  相似文献   
83.
Thiazoles are important scaffolds in organic chemistry. Biosynthesis of thiazoles is considered to be an excellent target for the design of novel classes of therapeutic agents. In this study, a new series of 2-ethylidenehydrazono-5-arylazothiazoles 5a–d and 2-ethylidenehydrazono-5-arylazo- thiazolones 8a–d were synthesized via the cyclocondensation reaction of the appropriate hydrazonyl halides 4a–d and 7a–d with ethylidene thiosemicarbazide 3, respectively. Furthermore, the thiosemicarbazide derivative 3 was reacted with different bromoacetyl compounds 10–12 to afford the respective thiazole derivatives 13–15. Chemical composition of the novel derivatives was established on bases of their spectral data (FTIR, 1H-NMR, 13C-NMR and mass spectrometry) and microanalytical data. The newly synthesized derivatives were screened for their in vitro anti-hepatic cancer potency using an MTT assay. Moreover, an in silico technique was used to assess the interaction modes of the compounds with the active site of Rho6 protein. The docking studies of the target Rho6 with the newly synthesized fourteen compounds showed good docking scores with acceptable binding interactions. The presented results revealed that the newly synthesized compounds exhibited promising inhibition activity against hepatic cancer cell lines (HepG2).  相似文献   
84.
Electrospinning is a versatile method for producing continuous nanofibers. It has since become an easy and cost-effective technique in the manufacturing process and drawn keen interests in most biomedical field applications. Nanofibers have garnered great attention in nanomedicine due to their resemblance with the extracellular matrix (ECM). Like nanoparticles, its unique characteristics of higher surface-to-volume ratio and the tunability of the polymers utilizing nanofiber have increased the efficiency in encapsulation and drug-loading capabilities. Smart or “stimuli-responsive” polymers have shown particular fascination in controlled release, where their ability to react to minor changes in the environment, such as temperature, pH, electric field, light, or magnetic field, distinguishes them as intelligent. Polymers are a popular material for the design of drug delivery carriers; consequently, various types of drugs, including antiviral, proteins, antibiotics, DNA and RNA, are successfully encapsulated in the pH-dependent nanofibers with smart polymers which is a polymer that can respond to change such as pH change, temperature. In this minireview, we discuss applications of smart electrospun pH-responsive nanofibers in the emerging biomedical developments which includes cancer drug targeting, oral controlled release, wound healing and vaginal drug delivery.  相似文献   
85.
COVID-19 is still a global pandemic that has not been stopped. Many traditional medicines have been demonstrated to be incredibly helpful for treating COVID-19 patients while fighting the disease worldwide. We introduced 10 bioactive compounds derived from traditional medicinal plants and assessed their potential for inhibiting viral spike protein (S-protein), Papain-like protease (PLpro), and RNA dependent RNA polymerase (RdRp) using molecular docking protocols where we simulate the inhibitors bound to target proteins in various poses and at different known binding sites using Autodock version 4.0 and Chimera 1.8.1 software. Results found that the chicoric acid, quinine, and withaferin A ligand strongly inhibited CoV-2 S -protein with a binding energy of −8.63, −7.85, and −7.85 kcal/mol, respectively. Our modeling work also suggested that curcumin, quinine, and demothoxycurcumin exhibited high binding affinity toward RdRp with a binding energy of −7.80, −7.80, and −7.64 kcal/mol, respectively. The other ligands, namely chicoric acid, demothoxycurcumin, and curcumin express high binding energy than the other tested ligands docked to PLpro with −7.62, −6.81, and −6.70 kcal/mol, respectively. Prediction of drug-likeness properties revealed that all tested ligands have no violations to Lipinski’s Rule of Five except cepharanthine, chicoric acid, and theaflavin. Regarding the pharmacokinetic behavior, all ligand predicted to have high GI-absorption except chicoric acid and theaflavin. At the same way chicoric acid, withaferin A, and withanolide D predicted to be substrate for multidrug resistance protein (P-gp substrate). Caffeic acid, cepharanthine, chicoric acid, withaferin A, and withanolide D also have no inhibitory effect on any cytochrome P450 enzymes. Promisingly, chicoric acid, quinine, curcumin, and demothoxycurcumin exhibited high binding affinity on SARS-CoV-2 target proteins and expressed good drug-likeness and pharmacokinetic properties. Further research is required to investigate the potential uses of these compounds in the treatment of SARS-CoV-2.  相似文献   
86.
Chronic periodontitis and diabetes mellitus share a two-way relationship, the common factor being the inflammatory-mediated pathway, and various cytokines are released during this inflammatory cascade, one of which being matrix metalloproteinase-9. The aim of this study was to identify whether the levels of matrix metalloproteinase-9 are increased due to type-II diabetes mellitus in chronic periodontitis patients. It was an observational, analytical, case-control study. Thirty subjects were recruited in the test group, who were suffering from type-II diabetes mellitus and chronic periodontitis, and 30 subjects in the control group, who were subjects with chronic periodontitis but systemically healthy. Periodontal parameters, including the plaque score, gingival bleeding index, probing pocket depth and clinical attachment level of the subjects, were measured, saliva samples of all of the subjects were collected and salivary matrix metalloproteinase-9 levels were analyzed by an enzyme-linked immunosorbent assay (ELISA) technique. The statistical analysis was performed using SPSS 24. Overall, the matrix metalloproteinase-9 levels of the diabetic patients with chronic periodontitis were increased almost twofold (156.95 ± 29.80 ng/mL) compared to the levels in the controls (74.96 ± 6.32 ng/mL) (p < 0.001). Similarly, the periodontal parameters were far worse in diabetics with chronic periodontitis compared to the controls. The average gingivitis score for the test subjects was 78.45 ± 8.93%), compared to 29.32 ± 12.96% in the controls (p < 0.001). The mean probing pocket depth for the test group was 5.39 ± 0.60 mm, and, for the control group, it was 4.35 ± 0.31 mm (p < 0.001). For the test subjects, the average clinical attachment level was 5.86 ± 0.58 mm, and it was 4.66 ± 0.32 mm for the controls (p < 0.001). It was ascertained that there is a two-fold increase in the levels of salivary matrix metalloproteinase-9 in the test group compared to the control group. In addition, the level of periodontal apparatus destruction was greater in the test group. This proved that type-II diabetes mellitus influences the levels of matrix metalloproteinase-9 in humans and elevates them, causing further periodontal destruction.  相似文献   
87.
 A reversed-phase high performance liquid chromatography (HPLC) method was developed, validated, and used for the quantitative determination of gatifloxacin (GA) and ambroxol hydrochloride (AM), from its tablet dosage form. Chromatographic separation was performed on a HiQ Sil C18 column (250 mm×4.6 mm, 5 μm), with a mobile phase comprising of a mixture of 0.01 mol/L potassium dihydrogen orthophosphate buffer and acetonitrile (70∶30, v/v), and pH adjusted to 3 with orthophosphoric acid, at a flow rate of 1 mL/min, with detection at 247 nm. Separation was completed in less than 10 min. As per International Conference on Harmonisation (ICH) guidelines the method was validated for linearity, accuracy, precision, limit of quantitation, limit of detection, and robustness. Linearity of GA was found to be in the range of 10-60 μg/mL and that for AM was found to be 5-30 μg/mL. The correlation coefficients were 0.9996 and 0.9993 for GA and AM respectively. The results of the tablet analysis (n=5) were found to be 99.94% with ±0.25% standard deviation (SD) and 99.98% with±0.36% SD for GA and AM respectively. Percent recovery of GA was found to be 99.92%-100.02% and that of AM was 99.86%-100.16%. The assay experiment shows that the method is free from interference of excipients. This demonstrates that the developed HPLC method is simple, linear, precise, and accurate, and can be conveniently adopted for the routine quality control analysis of the tablet.  相似文献   
88.
Poly(ε-caprolactone) (PCL), an aliphatic polyester paved the way in the formation of biodegradable and biocompatible polymer particles in tissue engineering and drug delivery applications. The factors affecting in the preparation of PCL particles such as influences of the concentration of PCL, molecular weight and concentration of poly(vinylpyrrolidone) (PVP) stabilizer, and the reaction time on the characteristics of PCL particles were investigated. In the fabrication of PCL particles, size, morphology and stability of the polymer particles were tailored by varying the type and concentration of the stabilizer to the polymer, reaction time and stirring speed of the reaction. Additionally, formation of particles was also related to the amount of PCL and PVP concentration. The PCL particles possessed a spherical shape with the size ranges of 5-20 micron and stability increases with higher concentration of PVP while coagulation observed when PCL particles prepared with the low concentration of PVP. The change in the morphology and sizes of the PCL particle at different reaction conditions were evaluated by scanning electron microscopy (SEM) analysis.  相似文献   
89.
Zingiber zerumbet, also known as ‘Lempoyang’, possesses various phytomedicinal properties, such as anticancer, antimicrobial, anti-inflammatory, antiulcer, and antioxidant properties. Secondary metabolites possessing such properties i.e., zerumbone and α-humulene, are found dominantly in the plant rhizome. Synergistic effects of plant growth hormones and elicitors on in vitro α-humulene and zerumbone production, and biomass growth, in adventitious root culture (AdRC) of Z. zerumbet cultivated in a two-stage culture are reported. The culture was induced by supplementation of 1.0 mg/L NAA and 2.0 mg/L IBA (dark), and subsequently maintained in medium supplemented with 1 mg/L NAA and 3 mg/L BAP (16:08 light-dark cycle), yielded the production of zerumbone at 3440 ± 168 µg/g and α-humulene at 3759 ± 798 µg/g. Synergistic elicitation by 400 μM methyl jasmonate (MeJa) and 400 μM salicylic acid (SA) resulted in a 13-fold increase in zerumbone (43,000 ± 200 µg/g), while 400 μM MeJa and 600 μM SA produced a 4.3-fold increase in α-humulene (15,800 ± 5100 µg/g) compared to control.  相似文献   
90.
Cancer remains one of the most crucial human malignancies with a higher mortality rate globally, and is predicted to escalate soon. Dysregulated ion homeostasis in cancerous cells prompted the researchers to investigate further ion homeostasis impeding agents as potent anticancerous agents. Reutilization of FDA-approved non-cancerous drugs has emerged as a practical approach to developing potent, cost-effective drugs for cancer treatment. Across the globe, most nations are incapable of fulfilling the medical demands of cancer patients due to costlier cancerous drugs. Therefore, we have inclined our review towards emphasizing recent advancements in cancer therapies involving ionophores utilization in exploring potent anticancer drugs. Numerous research reports have established the significant anticancerous potential of ionophores in several pre-clinical reports via modulating aberrant cell signaling pathways and enhancing antitumor immunity in immune cells. This review has mainly summarized the most significant ion homeostasis impeding agents, including copper, zinc, calcium, and polyether, that presented remarkable potential in cancer therapeutics via enhanced antitumor immunity and apoptosis induction. Altogether, this study could provide a robust future perspective for developing cost-effective anticancerous drugs rapidly and cost-effectively, thereby combating the limitations of currently available drugs used in cancer treatment.  相似文献   
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